Article

Fairy Lights in Femtoseconds: Aerial and Volumetric Graphics Rendered by Focused Femtosecond Laser Combined with Computational Holographic Fields

Authors:
  • Pixie Dust Technologies, Inc.
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Abstract

We present a method of rendering aerial and volumetric graphics using femtosecond lasers. A high-intensity laser excites a physical matter to emit light at an arbitrary 3D position. Popular applications can then be explored especially since plasma induced by a femtosecond laser is safer than that generated by a nanosecond laser. There are two methods of rendering graphics with a femtosecond laser in air: Producing holograms using spatial light modulation technology, and scanning of a laser beam by a galvano mirror. The holograms and workspace of the system proposed here occupy a volume of up to 1 cm^3; however, this size is scalable depending on the optical devices and their setup. This paper provides details of the principles, system setup, and experimental evaluation, and discussions on scalability, design space, and applications of this system. We tested two laser sources: an adjustable (30-100 fs) laser which projects up to 1,000 pulses per second at energy up to 7 mJ per pulse, and a 269-fs laser which projects up to 200,000 pulses per second at an energy up to 50 uJ per pulse. We confirmed that the spatiotemporal resolution of volumetric displays, implemented with these laser sources, is 4,000 and 200,000 dots per second. Although we focus on laser-induced plasma in air, the discussion presented here is also applicable to other rendering principles such as fluorescence and microbubble in solid/liquid materials.

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... Presentation of the graph is currently still using a special device, experience still has discomfort in a physiological perspective [19]. Because of this, holographic display are developed, where the container used is air, as in figure 1 made by ref. [19][20][21][22][23][24][25][26][27][28][29][30]. The technique of making holograms is called holography, this technique has been widely used and developed by researchers, on ASTESJ ISSN: 2415-6698 the other hand the technology used is still not able to be used by the general public, because based on the size of the hardware and system it still requires a lot of development. ...
... In Table 1 can be seen the research of Kimura et al. (2006) [20] and Saito et al. (2008) [21], produces 100 and 1000 Dot / Sec, but has not been able to produce a hologram. Then in the study of Ochiai et al. (2016) holograms can be produced using femtosecond lasers with energies of 30-100fs, 2mJ and 269fs, 50μJ with 1 color [22]. Then developed again by Hayasaki and Kumagai (2018), where the hologram has several colors produced from femtosecond lasers with energy <100fs, 4.3μJ [19] (see figure 1). ...
... In Table 1 can be seen the research of Kimura et al. (2006) [20] and Saito et al. (2008) [21], produces 100 and 1000 Dot / Sec, but has not been able to produce a hologram. Then in the study of Ochiai et al. (2016) holograms can be produced using femtosecond lasers with energies of 30-100fs, 2mJ and 269fs, 50μJ with 1 color [22]. Then developed again by Hayasaki and Kumagai (2018), where the hologram has several colors produced from femtosecond lasers with energy <100fs, 4.3μJ [19] (see figure 1). ...
... In addition, A3D displays using light field technologies like integral photography [1] avoid the vergence-accommodation conflict (VAC) [2] that brings visual discomfort [3], which is one of the issues with stereoscopic vision using special glasses. These characteristics can also be achieved by volumetric displays [4] that directly show voxels on a physical space by projecting light into physical objects [5], [6] or by using light emission [7], [8]. In this study, we distinguish A3D displays from autostereoscopic displays [9] that project exactly two views, one for each eye. ...
... A direct approach to increase the depth reconstruction range is to develop a flat display with denser pixels, but it is still challenging to obtain the sufficient depth reconstruction range. Similarly, volumetric displays [5]- [8] have the same limitation on their depth reconstruction ranges, as their displayable areas are physically bound by the size of their equipment or the room. Enlarging the areas requires significant hardware updates and/or construction work, which makes it difficult to expect home use with these technologies. ...
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... However, such displays can only represent images as two-dimensional arrays, typically on a flat surface. To render digital data sets in three dimensions, femtosecond lasers can for example be used to generate luminous voxels by locally ionizing the ambient air [39]. But this technology requires an elaborate setup and is currently limited to volumes of a cubic millimeter. ...
... 39 shows the functionality of the third additively manufactured liquid lens (which has a connection between the top and bottom membranes). The image of a checkerboard pattern is shown, projected through the liquid lens in its relaxed state (3.39 a) and when the pressure is increased(3.39 ...
Chapter
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... Mid-air haptics is a growing field which aims to move the interaction from touch surfaces to touchless interactive spaces in 3D. Hence technologies such as air-jet [28], air-vortexes [24], laser [12,22], electric arc [25], and ultrasonic-phased array [3,7] were developed to provide mid-air tactile feedback to the user, without requiring augmentation with extra wearables. Among those technologies, ultrasonic phased arrays are particularly proficient at rendering a range of complex tactile patterns on the user's palm or fingertips. ...
... Other approaches to produce mid-air tactile stimuli include the use of lasers [12,22] or the use of electric arcs [25]. Even though the stimulus size is very fine in such approaches, the interaction zone remains limited. ...
Conference Paper
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... Accordingly, the NA of the system is decreased, as expected in Eqs. (9) and (10). The reconstruction results in Fig. 9 are also degraded as f gp decreases when z h is fixed. ...
... When z h is increased, with the fixed f gp , the reconstruction results are degraded by following Eqs. (9) and (10) as well, though the image is magnified more. The degradation of the reconstructed image with an inappropriate selection of f gp and z h is easily notified by examining the decreasing PSNR value as well. ...
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The video recording–capable compact incoherent digital holographic camera system is proposed. The system consists of the linear polarizer, convex lens, geometric phase lens, and the polarized image sensor. The Fresnel hologram is recorded by this simple configuration in real time. The system parameters are analyzed and evaluated to record a better-quality hologram in a compact form-factor. The real-time holographic recording and its digitally reconstructed video playback are demonstrated with the proposed system.
... Each volume element (voxel) of a 3D object is physically present at the required location and thus a natural visual perception is afforded from the surrounding. A variety of volumetric displays are intensively studied to achieve next-generation human-computer interaction and other applications [3][4][5][6][7][8][9][10][11][12]. ...
Preprint
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... A volumetric display is a 3D display that is achieved by generating floating pixels in a transparent volume. Floating pixels had achieved by methods like plasma luminous body [6,7], fluorescence [8], acoustic levitation [9], photophoretic optical trapping [10], and scanning with a time-multiplexed 2D image [1]. These methods are fundamentally full-parallax and wide-viewing zone compared to other autostereoscopic displays. ...
Article
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... In these methods, the speed of objects floating in the air is limited by their control mechanisms. Ochiai et al. [11] realized the rendering of volumetric graphics in the air using femtosecond lasers. However, laser-based methods require adequate safety precautions. ...
Article
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Mid-air images, which are augmented reality (AR) technologies, enable computer graphics (CG) images to be superimposed on a physical space. The mid-air image can be placed side-by-side with real objects, allowing various interactions, such as directly manipulating them to contact the mid-air image on the same plane. In this case, the measurement of the shape of real objects is necessary to realize geometric consistency between the mid-air image and real objects. However, in mid-air image optics, real objects cannot be placed behind the mid-air image (i.e., at a position where they interrupt the light rays that form the mid-air image). This limits the placement of the sensor and may prevent accurate measurement of the shape of the real objects. Consequently, we proposed an optical system for interaction with mid-air images that virtually measures the shape of real objects from behind the mid-air image. In our system, a virtual infrared (IR) sensor is formed behind the mid-air image using a hot mirror that reflects only IR light. The optical system considers the visible area of the mid-air image and the measurable area of the sensor. We evaluated the sharpness, luminance, and chromaticity to assess whether the hot mirror had changed the appearance of the mid-air image. The results confirmed that there was little impact on user perception. Furthermore, we developed four supporting applications for our system to show its efficacy.
... It is even possible, instead of using fog as a screen, to use volumetric displays with plasma. Its system uses laser-induced plasma to emit light and scan with a Galvano mirror to project holographic images (Ochiai, 2015). Another method used to project a holographic image is the light field projection technique. ...
Conference Paper
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In marketing communication, 3D holograms, as a three-dimensional image that creates deception with the help of laser waves, are increasingly used to provide consumers with unforgettable experiences. Whether hologram images are projected on billboards, virtual catalogs, or are used during promotional events, diffraction of light and the production of a three-dimensional image of a product-which is currently of extremely high quality-cause a factor of surprise. The employment of holographic technologies in marketing can help the business not only connect with the younger generation, which uses digital technology the most, but also establish the brand as unique and forward-thinking. The hologram market is expected to grow by 30% in the next five years due to the recent rapid advancement of these technologies. It is already possible to generate holographic representations of goods that let customers touch them, and even feel their textures and temperature, this is achieved by using air jets to imitate resistance of the hologram projection, artificially stimulating the consumer's senses in that way. When consumers interact with hologram projections, this type of (digital) sensory stimulation can help them imagine themselves as future users of actual products, which ultimately has a beneficial impact on their purchase decision. Holographic displays that offer 360-degree viewing angles to customers have particularly grown in popularity since they produce very good video quality and appear almost exactly like real objects. The consumer's encounter with a holographic presentation, which is enriched with effective graphic elements and fast movements, is awe-inspiring, pleasant to look at and creates positive associations with the product presented with this technology. Such items will be seen by customers as novel and exciting in the marketplace, which can create strong emotional bonds between customers and the brand. Keywords: 3D Holograms, Marketing Communication, Consumers
... Some researchers have used volumetric display technology to display 3D images in the air. The most representative one is Fairy Lights of University of Tsukuba in 2015 8 . Although their imaging volume is only 1 cm 3 , the images are clear and vivid. ...
Conference Paper
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Three-dimensional holographic display can provide more possibilities for the human-machine interaction in the future smart cockpit. In this paper, potential application scenarios and interaction principles of holographic display in the future automotive cockpits are predicted. VACP model is utilized to validate the interaction principles, based on the analysis and evaluation of existing and potential cutting-edge holographic display technologies. Two application patterns are set up: before 2040, the role of driver still exists; due to the development of automated driving technology, participants will include only passengers after 2040, which means different interaction models and logics. After 2040, direct air projection technology will be applied, which is medium-free and with better interactive performance. Based on proposed principles, models as well as a series of user survey, application scenarios in the future cockpit are assumed. Through systematic technical analysis by cooperating with a prominent automobile OEM and other related industrial cooperators, this paper provides the principles and application concepts of holographic display in the future cockpit, and obtains the evaluation and test methods for holographic display technologies in these concepts at the same time.
... Later, there was research on a method of presenting tactile sensations without the device making direct contact with the body [1,2,3,4] and research [38] on rendering volumetric graphics that can be touched in the air using femtosecond laser-pulsed plasma. ...
Preprint
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Social interaction begins with the other person's attention, but it is difficult for a d/Deaf or hard-of-hearing (DHH) person to notice the initial conversation cues. Wearable or visual devices have been proposed previously. However, these devices are cumbersome to wear or must stay within the DHH person's vision. In this study, we have proposed SHITARA, a novel accessibility method with air vortex rings that provides a non-contact haptic cue for a DHH person. We have developed a proof-of-concept device and determined the air vortex ring's accuracy, noticeability and comfortability when it hits a DHH's hair. Though strength, accuracy, and noticeability of air vortex rings decrease as the distance between the air vortex ring generator and the user increases, we have demonstrated that the air vortex ring is noticeable up to 2.5 meters away. Moreover, the optimum strength is found for each distance from a DHH.
... They are based on light-scattering oremitting points and offer unconstrained visibility anywhere around the display. Some of those volumetric displays operate in mid-air with no barrier between user and image (referred to as free-space displays) and can be created using plasma [1,2], mirage [3] and scanning particles using light [4] and electromagnetic field [5]. However, none of these approaches rely on operating principles that can produce tactile and audio content as well. ...
Conference Paper
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The Multimodal Acoustic Trapping Display (MATD) makes use of ultrasound to trap, quickly move and color a particle, to create volumetric shapes in mid-air. Using the pressure delivered by ultrasound, the MATD can also create high-pressure points that our hands can feel and induce air vibrations that create audible sound.
... We previously proposed a display system that realizes volumetric graphics in the air by combining femtosecond-laser-excited aerial voxels with a beam design technique based on computer-generated holograms (CGHs) 24 . Since the system does not keep to capture a scatted particle and enables to draw robust images that does not disappear even after contact with users and real objects, it demonstrated not only aerial volumetric image but also touch interaction with images and real-world augmented reality. ...
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A volumetric display generates a graphics that can be viewed from 360∘ by representing the 3D information of an object as voxels in physical space. However, the natural properties of physical objects, such as 3D information and colors, and the seamless relationships between graphics and humans make it difficult to implement such displays. Here, we introduce a novel system that combines the spatial generation of femtosecond-laser-excited emission points using computer-generated holograms and beam scanning with the drawing space separation method. We demonstrate the drawing of volumetric graphics that can be color-expressed in voxel units in the air. This system enables the drawing of volumetric graphics in the air, accurate color representations, and robust graphics that are not destroyed by contact with users or objects. It also lays the foundation for the implementation of future volumetric displays.
... Hinges, telescoping, bendable/stretchable materials, disassembly/reassembly, gears, levers, or engines allow physical things to be varied in size/shape, but these capacities for transformation are still constrained by their materiality. 2 Researchers have demonstrated the proof-of-concept that tangible holographic images can be projected into real space (e.g.,Ochiai et al. 2016). We set such inscriptions aside because the technologies needed to display and interact with them are not yet commercially available. ...
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... Technologies such as pressurized air jets [16] or air vortex rings [18] can provide strong but rough feedback with some inherent time lag. Lasers [8,11] or electric arcs [17] are possible for very precise short range feedback. ...
Chapter
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Ultrasonic tactile stimulation can give the user contactless tactile feedback in a variety of human-computer interfaces. Parameters, such as duration, rhythm, and intensity, can be used to encode information into tactile sensation. The present aim was to investigate the differentiation of six ultrasonic tactile stimulations that were varied by form (i.e., square and circle) and timing (i.e., movement speed and duration, and the number of repetitions). Following a stimulus familiarization task participants (N = 16) were to identify the stimuli presented in the same order as in the familiarization phase. Overall, the results showed that it was significantly easier to identify stimuli that were rendered at a slower pace (i.e., longer duration) regardless of the number of repetitions. Thus, for ultrasonic haptics, rendering time was one important factor for easy identification.
... On the other hand, volumetric approaches are based on light-scattering, -emitting or -absorbing surfaces and offer unconstrained visibility anywhere around the display. Some of those volumetric displays operate in air with no barrier between user and image (thus referred to as free-space displays) and can be created using dusts [2], plasma [3,4], mirage [5] and scanning particles using light [6] and electromagnetic field [7]. However, none of these approaches rely on operating principles that can produce tactile and audio content as well. ...
Conference Paper
Full-text available
Current display approaches, such as VR, allow us to get a glimpse of multimodal 3D experiences, but users need to wear headsets as well as other devices in order to trick our brains into believing that the content we are seeing, hearing or feeling is real. Light-field, holographic or volumetric displays avoid the use of headsets, but they constraint the user’s ability to interact with them (e.g. content is not reachable to user’s hands, user’s constrained to specific locations) and, most importantly, still cannot simultaneously deliver sound and touch. In this talk, we will present the Multimodal Acoustic Trapping Display (MATD): a mid-air volumetric display that can simultaneously deliver visual, tactile and audio content, using phased arrays of ultrasound transducers. The MATD makes use of ultrasound to trap, quickly move and colour a small particle in mid-air, to create coloured volumetric shapes visible to our naked eyes. Making use of the pressure delivered by the ultrasound waves, the MATD can also create points of high pressure that our bare hands can feel and induce air vibrations that create audible sound. The system demonstrates particle speeds of up to 8.75 m/s and 3.75 m/s in the vertical and horizontal directions, respectively. In addition, our technique offers opportunities for non-contact, highspeed manipulation of matter, with applications in computational fabrication and biomedicine.
... The next-generation display may instead scan many particles through a simple path [ Fig. 2(b)]. Similar approaches for multiple voxel generation have been shown previously [16,17]. As previously mentioned, changing to parallel optical beams will allow the reduction from dual-axis scanning to single-axis scanning. ...
Article
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Since the introduction of optical trap displays in 2018, there has been significant interest in further developing this technology. In an effort to channel interest in the most productive directions, this work seeks to illuminate those areas that, in the authors’ opinion, are most critical to the ultimate success of optical trap displays as a platform for aerial 3D imaging. These areas include trapping, scanning, scaling, robustness, safety, and occlusion.
... Light is employed to provide sensation on the hands when the user is experiencing thermal radiation [16]. Nanosecond lasers applied to the skin induce a tactile sensation [17] . To date, radiofrequency and superconducting forces have not been applied to aerial haptic feedback. ...
Preprint
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... In recent years, three-dimensional (3D) display has gained widespread attraction and has gradually been integrated into our life. Compared with other 3D technologies such as holographic [1], volumetric [2], and light field displays [3,4], integral imaging has proved to be an efficient way to reproduce full-parallax and full-color 3D images without any environmental restrictions. Moreover, integral imaging can capture and reconstruct both spatial and directional information of the 3D scene based on the lens array [5][6][7][8][9][10][11]. ...
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In this paper, we present a 2D/3D mixed system with high image quality based on integral imaging and a switchable diffuser element. The proposed system comprises a liquid crystal display screen, lens array, switchable diffuser element and projector. The switchable diffuser element can be controlled to present 2D/3D mixed images or 2D and 3D images independently, and can reduce the Moire fringe and black grid. In addition to the improved display quality, the proposed system has advantages of a simple structure and is low cost, which contribute to the portability and practicability.
... digital signage, security systems, and entertainment) by implementing the algorithm on controllable color points instead of laser-induced points. A practical way to realize such points in the real world is to use volumetric displays [20,21], for example, plasma in air [22][23][24], photoluminescent materials [25][26][27][28], scattering bubbles in liquids [29], and levitated particles [30,31]. Combining with volumetric display technologies would enable our method to provide personalized information to multiple users dynamically and individually. ...
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We present a new refraction-based approach to embed multiple images into a single volume structure rendered on a glass solid (3D crystal). Each of the images can only be revealed when looked at from the certain viewpoint. While configurations of viewing directions in conventional methods are limited, our method can compensate for refractive effects at glass surfaces regardless of the viewing directions and enable the viewing directions to be set more flexibly, even allowing for 180 ∘ opposite projection by leveraging refraction. These unique features are verified with prototyping of 3D crystals projecting multiple grey-scale images and numerical assessments. In addition, we present a color dynamic representation of our method with computer graphics to demonstrate the potential use of our method as a novel information service system.
... As airborne tactile presentation techniques, air jet [1], vortex ring [2], laser [3] [4], and ultrasound waves [5] have been proposed. Among these, ultrasound approach has higher spatial and temporal resolution. ...
... The majority of static systems create a displaying area by using air or some special materials, such as LEDs, gases, solids, or particles. In the type of emission, the "voxels" are an active light source, [71][72][73][74][75] such as 3D LEDs array controlled by a computer, that can be used to run preprogrammed animations; upconversion conceptbased technology needs to employ gas or solid medium as 3D display space and makes the energy from two laser beams intersected in the space to form a luminous "voxel"; laser-induced plasma technology does not require special materials arranged and suspended in air to emit light. As an example, a method of rendering aerial and volumetric graphics by using femtosecond lasers offers clear, tiny, and touchable plasma images. ...
Article
Tabletop three‐dimensional (3D) display is an attractive display technology that allows multiple individuals around the table to view the reconstructed 3D objects simultaneously, which can be applied to a variety of application scenarios such as desktop conference and board games. In this review paper, the tabletop true 3D display has been characterized and classified into four categories based on the technologies of light field display, integral imaging, and volumetric 3D and holographic 3D displays. Moreover, the comparisons of these technologies are listed, and the prospect of the tabletop 3D display is discussed. Tabletop 3D display is an attractive display that allows multiple individuals around the table to view the reconstructed 3D objects simultaneously, which can be applied to various application scenarios. In this review paper, the tabletop true 3D display has been characterized and classified. The comparisons of different technologies are listed, and the prospect of the tabletop 3D display is discussed.
... However the image is not stereoscopic, and it is difficult to make complex interaction with a 3DCG object. "Fairy Light" can display a 3DCG object in mid-air by femtosecond lasers and can interact with them by a finger [Ochiai et al. 2015]. However the 3DCG object is quite small Permission to make digital or hard copies of part or all of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. ...
Conference Paper
We propose a novel system that enables a user to see stereoscopic 3DCG images in mid-air and interact with them directly as shown in Figure 1. This system displays 3DCG objects with motion parallax. Thus the user can observe them in mid-air while feeling a stereoscopic effect by the motion parallax. It is also possible to interact with the mid-air 3DCG objects by fingers. The user can move, deform and draw 3DCG objects as if they were there.
... These light sources are the 3-D analog of pixels and are called voxels. Earlier designs of volumetric displays were table-top designs and the displayed volume was confined to the physical volume of the display [3,6,33,35,40,41]. One of the limitations of most of these displays is that the light sources are presented additively and view-dependent effects, such as occlusion, are absent. ...
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We introduce an optical design and a rendering pipeline for a full-color volumetric near-eye display which simultaneously presents imagery with near-accurate per-pixel focus across an extended volume ranging from 15cm (6.7 diopters) to 4M (0.25 diopters), allowing the viewer to accommodate freely across this entire depth range. This is achieved using a focus-tunable lens that continuously sweeps a sequence of 280 synchronized binary images from a high-speed, Digital Micromirror Device (DMD) projector and a high-speed, high dynamic range (HDR) light source that illuminates the DMD images with a distinct color and brightness at each binary frame. Our rendering pipeline converts 3-D scene information into a 2-D surface of color voxels, which are decomposed into 280 binary images in a voxel-oriented manner, such that 280 distinct depth positions for full-color voxels can be displayed.
... 6). Among volumetric systems, we are aware of only three such displays that have been successfully demonstrated in free space: induced plasma displays [7][8][9] , modified air displays 10,11 and acoustic levitation displays 12 . Plasma displays have yet to demonstrate RGB colour or occlusion in free space. ...
... 49 Prêmio concedido pelo festival austríaco Ars Eletronica desde 1987. 50 David Bohm (1917 foi um físico norte-americano de posterior cidadania brasileira e britânica. É considerado um dos físicos teóricos mais importantes do século XX. ...
Research
The present exploratory research aims to investigate the history of holographic art in an attempt to understand the reasons for its discontinuity, if indeed this occurred and the factors that provoked it. The main theoretical reference is the recent book 3D History, Theory and Aesthetics of Transplane Image of German researcher Jens Schröter, University of Siegen. Time and space are basic and fundamental elements not only of all multimedia art but also of the deeper philosophical questions concerning the nature of reality, ontology.
... On-object screens behave similarly to projection based augmentation, yet they do not suffer from occlusions at the cost of object instrumentation. Mid-air spatial displays (i.e., without a supporting surface) are currently under research, using either: a fine particle suspension as support [204], fast moving objects [96], or complex systems to release photons at arbitrary locations in mid-air [145]. ...
Thesis
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In recent history, computational devices evolved from simple calculators to now pervasive artefacts, with which we share most aspects of our lives, and it is hard to imagine otherwise. Yet, this change of the role of computers was not accompanied by an equivalent redefinition of the interaction paradigm: we still mostly depend on screens, keyboards and mice. Even when these legacy interfaces have been proven efficient for traditional tasks, we agree with those who argue that these interfaces are not necessarily fitting for their new roles. Even more so, traditional interfaces preserve the separation between digital and physical realms, now counterparts of our reality.During this PhD, we focused the dissolution of the separation between physical and digital, first by extending the reach of digital tools into the physical environment, followed by the creation of hybrid artefacts (physical-digital emulsions), to finally support the transition between different mixed realities, increasing immersion only when needed. The final objective of this work is to augment the experience of reality. This comprises not only the support of the interaction with the external world, but also with the internal one. This thesis provides the reader contextual information along with required technical knowledge to be able to understand and build mixed reality systems. Once the theoretical and practical knowledge is provided, our contributions towards the overarching goal of merging physical and digital realms are presented. We hope this document will inspire and help others to work towards a world where the physical and digital, and humans and their environment are not opposites, but instead all counterparts of a unified reality.
... Another completely different challenge is mid-air tactile stimuli produced by direct laser irradiation to the skin for relatively short period [4]. It also generates a mid-air image as well as stinging texture in the air. ...
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In this paper, we report on an airborne vibrotactile display with a multiunit ultrasound phased array synthetic aperture. The system generates an ultrasound field with a location-tunable focus in the air, which exerts time-variant acoustic radiation pressure on the user's skin, resulting in perceivable localized vibrotactile stimuli. The paper contains three major new contributions from previous related works. The first is an experimental validation of large-aperture focusing with improved synchronization offering an enlarged workspace in which sufficient acoustic power concentration is guaranteed. From the experiments, it is expected that perceivable vibrotactile focus can be generated 1 m away from a four-unit array system. The second is an experimental evaluation of the presented pressure for producing a broad variety of tactile perception, which shows that the generated ultrasound focus can serve as an vibrotactile actuator that has flat frequency characteristics in the domain of perceptual stimuli. The third is a psychophysical result of the detection threshold curve for sinusoidal stimuli offered by the system. The obtained curve shows similarity with conventionally known results, which have minimum values at approximately 200 Hz.
... 6). Among volumetric systems, we are aware of only three such displays that have been successfully demonstrated in free space: induced plasma displays [7][8][9] , modified air displays 10,11 and acoustic levitation displays 12 . Plasma displays have yet to demonstrate RGB colour or occlusion in free space. ...
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Free-space volumetric displays, or displays that create luminous image points in space, are the technology that most closely resembles the three-dimensional displays of popular fiction. Such displays are capable of producing images in 'thin air' that are visible from almost any direction and are not subject to clipping. Clipping restricts the utility of all three-dimensional displays that modulate light at a two-dimensional surface with an edge boundary; these include holographic displays, nanophotonic arrays, plasmonic displays, lenticular or lenslet displays and all technologies in which the light scattering surface and the image point are physically separate. Here we present a free-space volumetric display based on photophoretic optical trapping that produces full-colour graphics in free space with ten-micrometre image points using persistence of vision. This display works by first isolating a cellulose particle in a photophoretic trap created by spherical and astigmatic aberrations. The trap and particle are then scanned through a display volume while being illuminated with red, green and blue light. The result is a three-dimensional image in free space with a large colour gamut, fine detail and low apparent speckle. This platform, named the Optical Trap Display, is capable of producing image geometries that are currently unobtainable with holographic and light-field technologies, such as long-throw projections, tall sandtables and 'wrap-around' displays.
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In the last decades interaction and interface design have created a variety of multimodal media technologies that are enhancing the processes of sensory media perception. It is interesting that developers are no longer focusing primary on visual and auditory characteristics, instead, they try to create new ways to establish haptic and tactile media potentials. This sensory turn has started a "technogenesis" (Hansen 2006, 9), because technological structures of media get synchronized with conditions of hapto-tactile perception and sensory inputs become embodied within the medium-as patterns of the specific design. The structure of hapto-tactile media is relating technology with the reception of the user, which means, that a progressive image science has to develop analytical concepts for a deeper understanding of potentials and possible side effects. Therefore, this article will develop image-theoretical concepts for the characterization of hyperaesthetic images: Images as elements of interactive and hapto-tactile media technologies are far more than clearly distinguishable two-dimensional picture surfaces, as due to enhanced perceptual processes they turn into multisensory images. The hyperaisthesis of haptic and tactile images is based on a multisensory activation, which transcends a pure visibility by synchronization of haptic and tactile stimuli, depicted representations and the specific sense modalities of the recipient: the hapto-tactile image can be specified as a triadic inter(re)active excitation pattern. The consequences of this assumption are far-reaching because image theory has to enhance analytical tools and methodologies with regard to a multimodality of perception. Classical views on images and visibility will be extremely tensed up. Therefore, hyperaesthetic
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Using threads and a projector, a directional volumetric display capable of moving images and full-color representation was developed in our previous work. However, the horizontal resolution of the directional volumetric display could only achieve 20 pixels with 400 threads. Further, the conventional algorithm requires P squared threads per P horizontal pixels of the input image. Because it is difficult to place a large number of threads, thus, a new algorithm for developing projected images to improve the directional volumetric display’s resolution was proposed. It is feasible to display images of P pixels with at least P threads using this technique. However, the higher the resolution, the lower the image quality in the proposed algorithm. Thus, it was verified how many threads can be used to display high-resolution images without degrading the image quality. Further, by representing the horizontal resolution of the input image with 5–6 threads per pixel, it is possible to display high-resolution images while maintaining the image quality. The proposed technique can display 64 pixels per 384 threads, whereas the conventional method can only display 20 pixels input images per 400 threads.
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Holographic structured illumination combined with optogenetics enables patterned stimulation of neurons and glial cells in an intact living brain. Moreover, in vivo functional imaging of cellular activity with recent advanced microscope technologies allows for visualization of the cellular responses during learning, emotion and cognition. Integrating these techniques can be used to verify the link between cell function and behavior output. However, there are technical limitations to stimulate multiple cells with high spatial and temporal resolution with available techniques of optogenetic stimulation. Here, we summarized a two-photon microscope combined with holographic system to stimulate multiple cells with high spatial and temporal resolution for living mice and their biological application.
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An optical setup comprising an external Fabry-Pérot (FP) cavity that maintains ultrashort pulse spatial and temporal coherence, is proposed to generate continuous sub-terahertz repetition rate ultrashort pulses (USP). Analytical results from different sets of pulse-to-pulse carrier-envelop phase offset ( ΔφCEO\Delta \varphi _{\mathrm {CEO}} ) output conditions manifest the possibility to extract and utilize the reflected USP signal from an ultrastable Pound-Drever-Hall phase-locked external FP cavity to stabilize or reset the ΔφCEO\Delta \varphi _{\mathrm {CEO}} to 0 or multiple of 2π2\pi rad in real time. The generation of a steady, ultrahigh repetition rate output, from a low repetition rate ultrashort pulse laser requires management of carrier-envelope phase (CEP). The CEP management with the passive external FP cavity group delay dispersion control enables transition from usual quasi- to continuous repetition rate. The net control and management of these parameters allow the passive external FP cavity multiplication factor to be increased above 200.
Chapter
The architecture of a decision support system for a reasonable choice of the characteristics of autostereoscopic displays is proposed. As a basic set of designs for autostereoscopic displays, the ones developed by the team of authors based on the original patented idea are proposed. It is based on the combined use of reference images using appropriate optical systems. This allows you to significantly reduce the requirements for the speed of information transmission channels, as well as to computers. The main attention is paid to the main modules of the decision support system, which is a hybrid expert system. A description is given of the interconnection in the form of an adjacency matrix between characteristics that affect the quality of the generated output volumetric image. The values of the coefficients of the influence of characteristics on the output image are described. A scheme has been developed for determining user and design characteristics of autostereoscopic displays. An example of determining the design characteristics of a given type of autostereoscopic displays using the proposed decision support system is given. It is advisable to use the obtained results in cyber-physical systems for designing systems using volumetric visualization tools.
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The three‐dimensional display is an important future land for the display industry. To reach a three‐dimensional display, several methods have been improved. For volumetric three‐dimensional display, due to a physical three‐dimensional display volume, the three‐dimensional image can provide an all‐around viewing without wearing any equipment. This article reviews several volumetric display methods using solid‐state volumetric display technology, free‐space volumetric technology, swept volume display technology combined with light field display technology. We discuss the benefits of using various display mediums and structure for a good performance in different situations.
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Mid-air imaging technology enables computer graphics (CG) images to move around in the real world. However, the big form-factor of large-format mid-air displays makes them bulky and limits their applicability. To reduce the size of such displays, we propose an optical design that realizes mid-air image movement by rotating the reflecting surface and the light source with motors and thus moving the virtual image of the light source. We made a prototype based on the calculation of the mirror and display angles and the distance between them and evaluated the luminance, sharpness, and position of the mid-air image of this prototype. We confirmed that the size of the prototype was smaller than that produced by the previous method, which will allow a smaller form-factor for creating mid-air images for different applications.
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The three‐dimensional display is an important future land for the display industry. To reach a three‐dimensional display, several methods have been improved. For volumetric three‐dimensional display, due to a physical three‐dimensional display volume, the three‐dimensional image can provide an all‐around viewing without wearing any equipment. This article reviews several volumetric display methods using solid‐state volumetric display technology, free‐space volumetric technology, swept volume display technology combined with light field display technology. We discuss the benefits of using various display mediums and structure for a good performance in different situations.
Thesis
We live exciting times where new types of displays are made possible, and current challenges focus on enhancing user experience. As examples, we witness the emergence of curved, volumetric, head-mounted, autostereoscopic, or transparent displays, among others, with more complex sensors and algorithms that enable sophisticated interactions.This thesis aims at contributing to the creation of such novel displays. In three concrete projects, we combine both optical and software tools to address specific applications with the ultimate goal of designing a three-dimensional display. Each of these projects led to the development of a working prototype based on the use of picoprojectors, cameras, optical elements, and custom software. In a first project, we investigated spherical displays: they are more suitable for visualizing spherical data than regular flat 2D displays, however, existing solutions are costly and difficult to build due to the requirement of tailored optics. We propose a low-cost multitouch spherical display that uses only off-the-shelf, low-cost, and 3D printed elements to make it more accessible and reproducible.Our solution uses a focus-free projector and an optical system to cover a sphere from the inside, infrared finger tracking for multitouch interaction, and custom software to link both. We leverage the use of low-cost material by software calibrations and corrections. We then extensively studied wedge-shaped light guides, in which we see great potential and that became the center component of the rest of our work. Such light guides were initially devised for flat and compact projection-based displays but in this project, we exploit them in a context of acquisition. We seek to image constrained locations that are not easily accessible with regular cameras due to the lack of space in front of the object of interest. Our idea is to fold the imaging distance into a wedge guide thanks to prismatic elements. With our prototype, we validated various applications in the archaeological field. The skills and expertise that we acquired during both projects allowed us to design a new transparent autostereoscopic display. Our solution overcomes some limitations of augmented reality displays allowing a user to see both a direct view of the real world as well as a stereoscopic and view-dependent augmentation without any wearable or tracking. The principle idea is to use a wedge light guide, a holographic optical element, and several projectors, each of them generating a different viewpoint. Our current prototype has five viewpoints, and more can be added. This new display has a wide range of potential applications in the augmented reality field.
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Science-fiction movies portray volumetric systems that provide not only visual but also tactile and audible three-dimensional (3D) content. Displays based on swept-volume surfaces1,2, holography3, optophoretics4, plasmonics5 or lenticular lenslets6 can create 3D visual content without the need for glasses or additional instrumentation. However, they are slow, have limited persistence-of-vision capabilities and, most importantly, rely on operating principles that cannot produce tactile and auditive content as well. Here we present the multimodal acoustic trap display (MATD): a levitating volumetric display that can simultaneously deliver visual, auditory and tactile content, using acoustophoresis as the single operating principle. Our system traps a particle acoustically and illuminates it with red, green and blue light to control its colour as it quickly scans the display volume. Using time multiplexing with a secondary trap, amplitude modulation and phase minimization, the MATD delivers simultaneous auditive and tactile content. The system demonstrates particle speeds of up to 8.75 metres per second and 3.75 metres per second in the vertical and horizontal directions, respectively, offering particle manipulation capabilities superior to those of other optical or acoustic approaches demonstrated until now. In addition, our technique offers opportunities for non-contact, high-speed manipulation of matter, with applications in computational fabrication7 and biomedicine8. A volumetric display that can simultaneously deliver visual, tactile and auditory content is demonstrated.
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In this article, we propose a new projection-based system to exhibit a realistic virtual cultural object in a museum. We introduce a new design by combining the multi-projection mapping technology with an optical see-through display that overcomes the limitations of the conventional projection-based exhibition by resolving the problems of ambient light and the occlusion by obstacles. We also introduce a mechanically moving projection surface that increases the degree of freedom of the projection content. Both geometric and radiometric calibration methods are used to correctly project a high-quality texture onto the moving 3D projection surface without perspective distortion. To evaluate the strength of the system and a potential for deployment in a general museum context, we conduct a user study that includes both the visitors and museum staff. The result shows that the proposed system can enrich the museum exhibition by creating a virtual cultural object with substantial 3D effect and high-fidelity appearance. We also demonstrate various applications of the system that provide dynamic content of a virtual cultural object by changing its appearance as well as the viewpoint.
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The levitation of optical scatterers provides a new means to develop free-space volumetric displays. The principle is to illuminate a levitating particle displaced at high velocity in three dimensions (3D) to create images based on the persistence of vision (POV). Light scattered by the particle can be observed all around the volumetric display and, therefore, provides a true 3D image that does not rely on interference effects and remains insensitive to the angle of observation. The challenge is to control with high accuracy and at high speed the trajectory of the particle in 3D. Here we use electrically driven planar Paul traps (PPTs) to control the trajectory of electrically charged particles. A single gold particle colloid is manipulated in 3D through AC and DC electrical voltages applied to a PPT. The electric voltages can be modulated at high frequencies (150 kHz) and allow for a high-speed displacement of particles without moving any other system component. The optical scattering of the particle in levitation yields free-space images that are imaged with conventional optics. The trajectory of the particle is entirely encoded in the electric voltage and driven through stationary planar electrodes. We show in this Letter the proof-of-concept for the generation of 3D free-space graphics with a single electrically scanned particle.
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We proposed a new type of dihedral corner reflector array (DCRA) called “radially arranged DCRA”. Our radially arranged DCRA could display a floating, three-dimensional image with a wide viewing angle without producing virtual images because dihedral corner reflectors were radially arranged for the designed paths of rays. In this research, we designed a reflector array pattern and evaluated the viewing angle of the floating image displayed by our radially arranged DCRA. During evaluation, we measured the reflection ratio of the radially arranged DCRA and demonstrated a floating image. Compared with a conventional DCRA, our radially arranged DCRA could expand the viewing angle from ± 30° to ± 90° without producing virtual images.
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Canlı veya nesne üzerine düşen ışığın kaydı olarak tanımlayabileceğimiz hologramlar, üç boyutlu (3B) görüntülerdir. Holografi ise hologram üretme yöntemine verilen addır. Holografik 3B görüntülemenin, arttırılmış gerçeklik ve sanal gerçeklik bağlamlarında düşünüldüğü ve bu konudaki sınıfl amalarda bir karışıklık olduğu görülmüştür. Arttırılmış gerçeklik ve sanal gerçeklik bağlamında düşünüldüğünde hologram uygulamalarını arttırılmış gerçekliğin bir boyutu olarak ele almak daha doğru görünmektedir. Zira sanal gerçeklik bireyi o anki dünyadan koparırken, arttırılmış gerçeklik bireyin o an içinde bulunduğu fiziksel mekânı dönüştürmektedir. Bu bölümde hologramların tarihçesinden bahsedilerek günümüzde geldiği boyut mercek altına alınmıştır. Kredi kartlarındaki etiketlerden, ekranlara taşınan serüvenini, ekrandan bağımsız biçimde havada süzülerek sürdüren hologramlar, iletişim, eğlence, pazarlama, kamu kurumları, mühendislik, tıp, sanat, sosyal bilimler ve eğitim gibi pek çok sektörde karşımıza çıkmaktadır. Hologramların sunum yöntemleri ve günümüzde kullanım durumları yapılan çalışmalarla örneklendirilmiştir. 3B hologram teknolojileri, yarattıkları yüksek gerçeklik algısı ile daha etkili ve çekici öğrenme süreçleri oluşturabilmek için önemli olanaklar sunmayı vadetmektedir. Eğitimde kullanımı ise henüz çok yeni olsa da mevcut çalışmalar incelenerek ana liz edilmiş ve çeşitli yönlerden tartışılmıştır. Apple, Microsoft ve Google gibi firmaların bu konudaki AR-GE çalışmalarını son hızla sürdürdüğü, Apple’ın gözlüksüz etkileşimli holografik dokunmatik ekran patentini alması ve Microsoft ’un üretime yönelik somut örneği olan HoloLens’i ortaya koyması yakın gelecekte bu teknolojiyi gündelik hayatta kullanıyor olacağımızı düşündürmektedir. Anahtar Kelimeler: hologram, 3B holografik görüntüleme, telebulunuşluk, eğitsel holografi
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In search of holograms that can be viewed from any angle.
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We discuss the concept of directness in the context of spatial interaction with visualization. In particular, we propose a model that allows practitioners to analyze and describe the spatial directness of interaction techniques, ultimately to be able to better understand interaction issues that may affect usability. To reach these goals, we distinguish between different types of directness. Each type of directness depends on a particular mapping between different spaces, for which we consider the data space, the visualization space, the output space, the user space, the manipulation space, and the interaction space. In addition to the introduction of the model itself, we also show how to apply it to several real-world interaction scenarios in visualization, and thus discuss the resulting types of spatial directness, without recommending either more direct or more indirect interaction techniques. In particular, we will demonstrate descriptive and evaluative usage of the proposed model, and also briefly discuss its generative usage.
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A holographic volumetric 3D display with images in real‐space is based on diffractive optical elements (DOE) and polychromatic illumination. Volume slices are generated at different physical depths via chromatic dispersion properties of a custom DOE fabricated with sub‐micron features. Illumination is based on laser/LED sources, filtering and DMD projection.
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We review our recent developments of volumetric display systems using holographic laser drawing technique achieved by a computer‐generated hologram displayed on a spatial light modulator. Three types of volumetric display systems using different screen media including multilayered fluorescent screen, air, and glycerin are demonstrated.
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Past research on shape displays has primarily focused on rendering content and user interface elements through shape output, with less emphasis on dynamically changing UIs. We propose utilizing shape displays in three different ways to mediate interaction: to facilitate by providing dynamic physical affordances through shape change, to restrict by guiding users with dynamic physical constraints, and to manipulate by actuating physical objects. We outline potential interaction techniques and introduce Dynamic Physical Affordances and Constraints with our inFORM system, built on top of a state-of-the-art shape display, which provides for variable stiffness rendering and real-time user input through direct touch and tangible interaction. A set of motivating examples demonstrates how dynamic affordances, constraints and object actuation can create novel interaction possibilities.
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The prime feature of the SplashDisplay is that it uses projectile beads as a display medium that are launched from the table; this means that the tangible medium can be removed from the surface and allowed free movement in air. In current research [1] [2], displays have tended toward fixed mediums and therefore defining and visualizing explosive activity on such displays has been difficult. However, the SplashDisplay is made for this particular purpose, and given the nature of the display medium it pulls away from conventional standard surfaces. Given this tradeoff, it is possible for the SplashDisplay to launch projectile beads from millimeters to meters into the air freely making it possible to attain an image 'depth' much like the Z-axis in 3D. In the simulation of 'explosions', this system launches beads into the air much like the physical phenomenon, making the projected object 'feel' like it actually exploded (Figure 1). As the beads are white in color, it is possible for these beads to act as a display backing. When the system is still, then the beads play the role of a stationary screen; once the beads are in air, they can still be recognized as 'screen' material. If light is projected onto these airborne beads, they will illuminate as they fall, giving a 'fireworks' like effect in real time.
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We present a novel D display that can show any 3D contents in free space using laser-plasma scanning in the air. The laser-plasma technology can generate a point illumination at an arbitrary position in the free space. By scanning the position of the illumination, we can display a set of point illuminations in the space, which realizes D display in the space. This D display has been already presented in Emerging Technology of SIGGRAPH2006, which is the basic platform of our D display project. In this presentation, we would like to introduce history of the development of the laser-plasma scanning 3D display, and then describe recent development of the 3D contents analysis and processing technology for realizing an innovative media presentation in a free 3D space. The one of recent development is performed to give preferred 3D contents data to the D display in a very flexible manner. This means that we have a platform to develop an interactive 3D contents presentation system using the 3D display, such as an interactive art presentation using the 3D display. We would also like to present the future plan of this D display research project.
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In this paper we report on our combined measurements of the visible lesion thresholds for porcine skin for wavelengths in the infrared from 810 nm at 44 fs to 1318 nm at pulse durations of 50 ns and 350mus to 1540 nm including pulse durations of 31 ns and 600 mus. We also measure thresholds for various spot sizes from less than 1 mm to 5 mm in diameter. All three wavelengths and five pulse durations are used extensively in research and the military. We compare these minimum visible lesion thresholds with ANSI standards set for maximum permissible exposures in the infrared wavelengths. We have measured non-linear effects at the laser-tissue interface for pulse durations below 1mus and determined that damage at these short pulse durations are usually not thermal effects. Damage at the skin surface may include acoustical effects, laser ablation and/or low-density plasma effects, depending on the wavelength and pulse duration. Also the damage effects may be short-lived and disappear within a few days or may last for much longer time periods including permanent discolorations. For femtosecond pulses at 810 nm, damage was almost instant and at 1 hour had an ED50 of 8.2 mJ of pulse energy. After 24 hours, most of the lesions disappeared and the ED50 increased by almost a factor of 3 to 21.3 mJ. There was a similar trend for the 1.318 mu laser for spot sizes of 2 mm and 5 mm where the ED50 was larger after 24 hours. However, for the 1.54 mu laser with a spot size of 5 mm, the ED50 actually decreased by a small amount; from 6.3 Jcm-2 to 6.1 Jcm-2 after 24 hours. Thresholds also decreased for the 1314 nm laser at 350 mus for spot sizes of 0.7 mm and 1.3 mm diameter after 24 hours. Different results were obtained for the 1540 nm laser at 600 mus pulse durations where the ED50 decreased for spot sizes 1 mm and below, but increased slightly for the 5 mm diameter spot size from 6.4 Jcm-2 to 7.4 Jcm-2
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A three-color, solid-state, volumetric display based on two-step, two-frequency upconversion in rare earth-doped heavy metal fluoride glass is described. The device uses infrared laser beams that intersect inside a transparent volume of active optical material to address red, green, and blue voxels by sequential two-step resonant absorption. Three-dimensional wire-frame images, surface areas, and solids are drawn by scanning the point of intersection of the lasers around inside of the material. The prototype device is driven with laser diodes, uses conventional focusing optics and mechanical scanners, and is bright enough to be seen in ambient room lighting conditions. QuickTime movie of the three-dimensional display.
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Mid-air displays which project floating images in free space have been seen in SF movies for several decades [Rakkolainen 2007]. Recently, they are attracting a lot of attention as promising technologies in the field of digital signage and home TV, and many types of holographic displays are proposed and developed. You can see a virtual object as if it is really hovering in front of you. But that amazing experience is broken down the moment you reach for it, because you feel no sensation on your hand.
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This paper presents ZeroN, a new tangible interface element that can be levitated and moved freely by computer in a three dimensional space. ZeroN serves as a tangible representation of a 3D coordinate of the virtual world through which users can see, feel, and control computation. To accomplish this, we developed a magnetic control system that can levitate and actuate a permanent magnet in a pre-defined 3D volume. This is combined with an optical tracking and display system that projects images on the levitating object. We present applications that explore this new interaction modality. Users are invited to place or move the ZeroN object just as they can place objects on surfaces. For example, users can place the sun above physical objects to cast digital shadows, or place a planet that will start revolving based on simulated physical conditions. We describe the technology and interaction scenarios, discuss initial observations, and outline future development.
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In contrast to light-emitting displays like plasma display panels (PDPs) and liquid crystal displays (LCDs), color-forming displays like "E-Ink" which displays information by reflecting surrounding light are being actively researched as a technology that is easy on the eye and can even be applied in bright places such as outdoors in sunlight. Applying photochromic materials (PM) for controlling color in this manner, Photochromic Canvas [Hashida et al. 2010] and Slow Display [Saakes et al. 2010], which are combined with projected-light systems, make it possible to control color without contact with the surface of an object. In this paper, the concept, namely, "contactless color control," is extended to volumetric space, and "volumetric color-forming pixels" are successfully created. This paper proposes a system referred to as "photochromic sculpture" which can generate a dynamically changeable 3D sculpture. (see Figure 1).
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Kinoforms (i.e., computer-generated phase holograms) are designed with a new algorithm, the optimal-rotation-angle method, in the paraxial domain. This is a direct Fourier method (i.e., no inverse transform is performed) in which the height of the kinoform relief in each discrete point is chosen so that the diffraction efficiency is increased. The optimal-rotation-angle algorithm has a straightforward geometrical interpretation. It yields excellent results close to, or better than, those obtained with other state-of-the-art methods. The optimal-rotation-angle algorithm can easily be modified to take different restraints into account; as an example, phase-swing-restricted kinoforms, which distribute the light into a number of equally bright spots (so called fan-outs), were designed. The phase-swing restriction lowers the efficiency, but the uniformity can still be made almost perfect.
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Fluorescence laser scanning microscopy (LSM) offers many advantages over conventional fluorescence microscopy. Very strong excitation light can be concentrated on small spots (0.5 μm) of the specimen, enabling the detection of low concentrations of fluorescent substances. The low levels of autofluorescence generated in the microscope objective and in the immersion oil in LSM provide images of great contrast, even with weakly fluorescent specimens. Confocal LSM permits the visualization of multiple focal layers of the specimen and 3-D image reconstructions. Combination of images stored in computer memory allow the comparison of phase contrast and fluorescence images of the same area of the specimen enabling multiparameter analysis of cells.
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We present an immaterial display that uses a generalized form of depth-fused 3D (DFD) rendering to create unencumbered 3D visuals. To accomplish this result, we demonstrate a DFD display simulator that extends the established depth-fused 3D principle by using screens in arbitrary configurations and from arbitrary viewpoints. The feasibility of the generalized DFD effect is established with a user study using the simulator. Based on these results, we developed a prototype display using one or two immaterial screens to create an unencumbered 3D visual that users can penetrate, examining the potential for direct walk-through and reach-through manipulation of the 3D scene. We evaluate the prototype system in formative and summative user studies and report the tolerance thresholds discovered for both tracking and projector errors.
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The display is the last component in a chain of activity from image acquisition, compression, coding transmission and reproduction of 3-D images through to the display itself. There are various schemes for 3-D display taxonomy; the basic categories adopted for this paper are: holography where the image is produced by wavefront reconstruction, volumetric where the image is produced within a volume of space and multiple image displays where two or more images are seen across the viewing field. In an ideal world a stereoscopic display would produce images in real time that exhibit all the characteristics of the original scene. This would require the wavefront to be reproduced accurately, but currently this can only be achieved using holographic techniques. Volumetric displays provide both vertical and horizontal parallax so that several viewers can see 3-D images that exhibit no accommodation/convergence rivalry. Multiple image displays fall within three fundamental types: holoform in which a large number of views give smooth motion parallax and hence a hologram-like appearance, multiview where a series of discrete views are presented across viewing field and binocular where only two views are presented in regions that may occupy fixed positions or follow viewers' eye positions by employing head tracking. Holography enables 3-D scenes to be encoded into an interference pattern, however, this places constraints on the display resolution necessary to reconstruct a scene. Although holography may ultimately offer the solution for 3DTV, the problem of capturing naturally lit scenes will first have to be solved and holography is unlikely to provide a short-term solution due to limitations in current enabling technologies. Liquid crystal, digital micromirror, optically addressed liquid crystal and acoustooptic spatial light modulators (SLMs) have been employed as suitable spatial light modulation devices in holography. Liquid crystal SLMs are generally favored owing to the c- - ommercial availability of high fill factor, high resolution addressable devices. Volumetric displays provide both vertical and horizontal parallax and several viewers are able to see a 3-D image that exhibits no accommodation/convergence rivalry. However, the principal disadvantages of these displays are: the images are generally transparent, the hardware tends to be complex and non-Lambertian intensity distribution cannot be displayed. Multiple image displays take many forms and it is likely that one or more of these will provide the solution(s) for the first generation of 3DTV displays.
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Despite recent interest in digital fabrication, there are still few algorithms that provide control over how light propagates inside a solid object. Existing methods either work only on the surface or restrict themselves to light diffusion in volumes. We use multi-material 3D printing to fabricate objects with embedded optical fibers, exploiting total internal reflection to guide light inside an object. We introduce automatic fiber design algorithms together with new manufacturing techniques to route light between two arbitrary surfaces. Our implicit algorithm optimizes light transmission by minimizing fiber curvature and maximizing fiber separation while respecting constraints such as fiber arrival angle. We also discuss the influence of different printable materials and fiber geometry on light propagation in the volume and the light angular distribution when exiting the fiber. Our methods enable new applications such as surface displays of arbitrary shape, touch-based painting of surfaces, and sensing a hemispherical light distribution in a single shot.
Conference Paper
In the past several years, the Display Systems Branch, Naval Ocean Systems Center (NOSC), has been involved in the development of laser based display systems with the goal of upgrading the image quality of shipboard displays. In this paper we report work on: (1) developing laser generated 3D volumetric images on a rotating double helix, (where the 3D displays are computer controlled for group viewing with the naked eye), and (2) system feasibility results along with the first and second generation component parameters.
Conference Paper
In contrast to light-emitting displays like plasma display panels (PDPs) and liquid crystal displays (LCDs), color-forming displays like "E-Ink" which displays information by reflecting surrounding light are being actively researched as a technology that is easy on the eye and can even be applied in bright places such as outdoors in sunlight. Applying photochromic materials (PM) for controlling color in this manner, Photochromic Canvas [Hashida et al.2010] and Slow Display [Saakes et al.2010], which are combined with projected-light systems, make it possible to control color without contact with the surface of an object. In this paper, the concept, namely, "contactless color control," is extended to volumetric space, and "volumetric color-forming pixels" are successfully created. This paper proposes a system referred to as "photochromic sculpture" which can generate a dynamically changeable 3D sculpture. (see Figure 1).
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We propose a novel graphics system based on the expansion of 3D acoustic-manipulation technology. In conventional research on acoustic levitation, small objects are trapped in the acoustic beams of standing waves. We expand this method by changing the distribution of the acoustic-potential field (APF). Using this technique, we can generate the graphics using levitated small objects. Our approach makes available many expressions, such as the expression by materials and non-digital appearance. These kinds of expressions are used in many applications, and we aim to combine them with digital controllability. In the current system, multiple particles are levitated together at 4.25-mm intervals. The spatial resolution of the position is 0.5 mm. Particles move at up to 72 cm/s. The allowable density of the material can be up to 7 g/cm(3). For this study, we use three options of APF: 2D grid, high-speed movement, and combination with motion capture. These are used to realize floating screen or mid-air raster graphics, mid-air vector graphics, and interaction with levitated objects. This paper reports the details of the acoustic-potential field generator on the design, control, performance evaluation, and exploration of the application space. To discuss the various noncontact manipulation technologies in a unified manner, we introduce a concept called "computational potential field" (CPF).
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Parallel optical access liquid volumetric display with computer-generated hologram is demonstrated. The volumetric display is composed of the luminous points excited by femtosecond pulses focused in a fluorescent solution with a XYZ scanner.
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We present an approach to 3D printing custom optical elements for interactive devices labelled Printed Optics. Printed Optics enable sensing, display, and illumination elements to be directly embedded in the casing or mechanical structure of an interactive device. Using these elements, unique display surfaces, novel illumination techniques, custom optical sensors, and embedded optoelectronic components can be digitally fabricated for rapid, high fidelity, highly customized interactive devices. Printed Optics is part of our long term vision for interactive devices that are 3D printed in their entirety. In this paper we explore the possibilities for this vision afforded by fabrication of custom optical elements using today's 3D printing technology.
Conference Paper
We previously developed a display using a soap film as a screen. This screen can display various appearances of the projected images by changing its reflectance property by controlling ultrasound waves. Further, the soap film has other advantages of being very thin and disposable. This research aims to make use of these advantages to realize new interactions with a display. The soap screen pops out and breaks. Users can insert their fingers into the screen. When the screen breaks, it can be replaced easily. This display is expected to contribute to entertainment computing communities by acting as a deformable and physically interactive display. In this paper, the details of the proposed display, the related experimental results, discussion and future work are presented.
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Display technology has undergone great progress over the last few years. From higher contrast to better temporal resolution or more accurate color reproduction, modern displays are capable of showing images which are much closer to reality. In addition to this trend, we have recently seen the resurrection of stereo technology, which in turn fostered further interest on automultiscopic displays. These advances share the common objective of improving the viewing experience by means of a better reconstruction of the plenoptic function along any of its dimensions. In addition, one usual strategy is to leverage known aspects of the human visual system (HVS) to provide apparent enhancements, beyond the physical limits of the display. In this survey, we analyze these advances, categorize them along the dimensions of the plenoptic function, and present the relevant aspects of human perception on which they rely.
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In the past several years, the Display Systems Branch, Naval Ocean Systems Center (NOSC), has been involved in the development of laser based display systems with the goal of upgrading the image quality of shipboard displays. In the paper we report work on: (1) developing laser generated 3D volumetric images on a rotating double helix (where the 3D displays are computer controlled for group viewing with the naked eye), and (2) system feasibility results along with the first and second generation component parameters.
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In this paper, we propose a novel method of representing the complex surface of a 3D object for a new aerial D display which can draw dots of light at an arbitrary position in a space. The aerial D display that we use in this research can create a dot of light at 50 kHz and can draw dots of light by vector scanning. The proposed method can generate point sequence data for the aerial D display from 3D surface models consisting of polygonal patches. The 3D surface model is polygonal model which are generally used in computer graphics. The proposed method represents the surface with contours consisting of intersections of an object and cross sections by a sequence of points for vector scanning. In this research, some polygonal models, for example face and hand, are examined at experiments. From the experiments of drawing, the polygonal models can successfully be drawn by the proposed method.
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The Embossed Touch Display is a novel tactile display that can present any given width of objects. When we touch objects in space, we actively move our hands and fingers. Due to this active touch movement, we can perceive the shape of an object, even ...
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The DepthCube 3D Volumetric Display is a solid state, rear projection, volumetric display that consists of two main components: a high-speed video projector, and a multiplanar optical element composed of a air-spaced stack of liquid crystal scattering shutters. The high-speed video projector projects a sequence of slices of the 3D image into the multiplanar optical element where each slice is halted at the proper depth. Proprietary multiplanar anti-aliasing algorithms smooth the appearance of the resultant stack of image slices to produce a continuous appearing truly three-dimensional image. The resultant 3D image is of exceptional quality and provides all the D vision cues found in viewing real object.
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We propose a holographic femtosecond laser processing system capable of parallel, arbitrary, and variable patterning. These features are achieved by introducing a spatial light modulator displaying a hologram into the femtosecond laser processing system. We demonstrate the variable parallel processing of a glass sample.
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We describe a set of rendering techniques for an autostereoscopic light field display able to present interactive 3D graphics to multiple simultaneous viewers 360 degrees around the display. The display consists of a high-speed video projector, a spinning mirror covered by a holographic diffuser, and FPGA circuitry to decode specially rendered DVI video signals. The display uses a standard programmable graphics card to render over 5,000 images per second of interactive 3D graphics, projecting 360-degree views with 1.25 degree separation up to 20 updates per second. We describe the system's projection geometry and its calibration process, and we present a multiple-center-of-projection rendering technique for creating perspective-correct images from arbitrary viewpoints around the display. Our projection technique allows correct vertical perspective and parallax to be rendered for any height and distance when these parameters are known, and we demonstrate this effect with interactive raster graphics using a tracking system to measure the viewer's height and distance. We further apply our projection technique to the display of photographed light fields with accurate horizontal and vertical parallax. We conclude with a discussion of the display's visual accommodation performance and discuss techniques for displaying color imagery.
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Lumen is an interactive display that presents visual images and physical, moving shapes, both controlled independently. The smooth, organic physical motions provide aesthetically pleasing, calm displays for ambient computing environments. Users interact with Lumen directly, forming shapes and images with their hands.
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A 360-degree-viewable volumetric 3-D display has been developed by Actuality Systems, Inc. It has a resolution of 768 x 768 x 198, has a 24 Hz volume refresh rate, contains an embedded graphics processing system, and uses dithering methods to create images of 3-bit to 21-bit-stippled color, which is perceived as several hundred colors. The 3-D display system is a visualization platform, comprised of a combination of hardware and software designed for ease-of-integration into existing visualization systems. The system design 1 is briefly recounted. Key enhancements are described, such as the development of a complete volumetric visualization platform. Examples are given which guide the system engineer who needs to include a volumetric display into a visualization solution.
Conference Paper
Recently, the field of media art has become popular. However, most existing media art works are not suitable to exhibit in a public space. To develop technologies that enable media art works to be exhibited in a public space, we pay attention to the "spatial coexistence between the real and the virtual in public spaces"; the audience in a public space can feel as if the virtual space and real space exist together completely. In this paper, we propose a new concept, named the "controllable particle display", which is to display threedimensional objects by filling space with small particles. On the basis of this concept we developed a prototype system using water drops as particles. In this system, a set of water drops, falling from a tank, are designed to form a plane surface. Patterns of images are projected upward on the falling water drops by a projector under the water drops. Three-dimensional objects can be observed by projecting a set of tomographic images in accordance with the position of the water drops. We also demonstrated the effectiveness of our concept and system.
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The display of three-dimensional information is considered with particular reference to a radar system in which a narrow pulsed beam of radio-frequency energy is used to explore automatically a volume of space. The three-dimensional displays are used to display the positions of the reflected ¿signals¿ with respect to the three co-ordinates of the volume, in order that the radar can be used as an object-detecting and -locating system in three dimensions. In the past, ¿configurational¿ methods have been used, wherein the shape of the intensity-modulated echo-trace on the cathode-ray tube is altered to add a third variable to the two already provided by the c.r.t. deflections. These types are not discussed, attention being concentrated on other methods. The ¿truly three-dimensional displays¿ utilize a mechanical motion to add a third dimension to the screen of the cathode-ray tube, the picture appearing as an actual volume. The ¿perspective displays¿ simulate the same picture as in the previous display without any moving mechanisms, rotation of the volume and/or stereoscopy being used to give the impression of three dimensions. The ¿oblique displays¿ obtain the required three co-ordinates by combinations of two or more two-co-ordinate pictures on the same cathode-ray tube. The ¿polychromatic displays¿ use colour to represent a spatial co-ordinate. The physiological and psychological problems of the human operator peculiar to three-dimensional displays are discussed, and a Section is included on the relative advantages of ¿true¿ and ¿relative¿ displays. Another Section on ¿display sensitivity¿ leads to the general theoretical considerations involved in three-dimensional displays. The application of three-dimensional displays to other fields, for example X-ray photography, is briefly discussed. The revised form of the radar equation for use with three-dimensional displays is given in an Appendix.
Conference Paper
In this paper, a method of representing 3D shape for the laser-plasma scanning 3D display devices using point cloud in consideration of hardware is proposed. A new device has been developed for 3D spatial displays. This device generates plasma luminous bodies produced by ldquolaser-induced breakdownrdquo in midair. In this method, objects are represented by point cloud so that the burden of the xyz-scanner, which controls the position of the plasma, becomes lighter. Additionally, the order of drawing 3D wireframe models can be decided in consideration of the scanner burden.
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The expressions for tunnel ionization probability of the complex atoms and atomic ions from arbitrary states in electromagnetic field are obtained. These expressions correctly describe the experimental data on rare gases atoms ionization in an infrared electromagnetic field.
Conference Paper
True 3D display systems like volumetric displays allow generation of autostereoscopic, multi-view 3D content that has real physical dimensions. However their uptake as a research tool within the HCI community is limited largely due to difficulties in buying or building such displays. The choice of commercially available systems is limited and constrains the flexibility of their use in terms of interaction capabilities, display features and integration with multi-display environments (MDEs). In this paper we describe the steps involved in creating custom volumetric display from easily available components. By building a touch-enabled volumetric display we walk-through the steps involved in the process. This will enable us to explore various interactive systems, associated techniques and challenges related to integration of the device into a MDE.
Conference Paper
Volumetric displays, which display imagery in true 3D space, are a promising platform for the display and manipu- lation of 3D data. To fully leverage their capabilities, ap- propriate user interfaces and interaction techniques must be designed. In this paper, we explore 3D selection techniques for volumetric displays. In a first experiment, we find a ray cursor to be superior to a 3D point cursor in a single target environment. To address the difficulties associated with dense target environments we design four new ray cursor techniques which provide disambiguation mechanisms for multiple intersected targets. Our techniques showed varied success in a second, dense target experiment. One of the new techniques, the depth ray, performed particularly well, significantly reducing movement time, error rate, and input device footprint in comparison to the 3D point cursor.
Conference Paper
Realizing a true three-dimensional (3D) display environment has been an ultimate goal of visual computing communities. Burton Inc. in Japan and others built upon the modern laser-plasma technology to come up with 3D Aerial Display device in 2006, with which the users are allowed to plot a unicursal series of illuminants freely in the midair, and thus the surrounding audience can enjoy watching different aspects of the 3D image from different positions, without any eye strain [Kimura et al. 2006].
Conference Paper
This paper presents work carried out for a project to develop a new interactive technique that combines haptic sensation with computer graphics. The project has two goals. The first is to provide users with a spatially continuous surface on which they can effectively touch an image using any part of their bare hand, including the palm. The second goal is to present visual and haptic sensation simultaneously by using a single device that doesn't oblige the user to wear any extra equipment. In order to achieve these goals, we designed a new interface device comprising of a flexible screen, an actuator array and a projector. The actuator deforms the flexible screen onto which the image is projected. The user can then touch the image directly and feel its shape and rigidity. Initially we fabricated two prototypes, and their effectiveness is examined by studying the observations made by anonymous users and a performance evaluation test for spatial resolution.
Conference Paper
Motion parallax is important to recognize the depth of a 3D image. In recent years, many D display methods that enable parallax images to be seen with the naked eye have been developed. In addition, there has been an increase in research to design interfaces that enable humans to intuitively interact with and operate 3D objects using their hands. However, realizing 3D object interaction as if the user is actually touching the object in the real world is quite difficult. One of the reasons for this is that the screen shape in conventional methods is restricted to a flat panel. In addition, it is difficult to achieve a balance between displaying the 3D image and sensing the user input. Therefore, we propose a novel full-parallax D display system that is suitable for interactive 3D applications. We call this system RePro3D. Our approach is based on a retro-reflective projection technology[Inami et al. 2000]. A number of images from a projector array are projected onto the retro-reflective screen. When a user looks at the screen through a half mirror, he or she, without the use of glasses, can view a 3D image that has motion parallax. We can choose the screen shape depending on the application. Image correction according to the screen shape is not required. Consequently, we can design a touch-sensitive soft screen, a complexly curved screen, or a screen with an automatically moving surface. RePro3D has a sensor function to recognize the user input. Some interactive features, such as operation of 3D objects, can be achieved by using it.
Article
Molecular excitation by the simultaneous absorption of two photons provides intrinsic three-dimensional resolution in laser scanning fluorescence microscopy. The excitation of fluorophores having single-photon absorption in the ultraviolet with a stream of strongly focused subpicosecond pulses of red laser light has made possible fluorescence images of living cells and other microscopic objects. The fluorescence emission increased quadratically with the excitation intensity so that fluorescence and photo-bleaching were confined to the vicinity of the focal plane as expected for cooperative two-photon excitation. This technique also provides unprecedented capabilities for three-dimensional, spatially resolved photochemistry, particularly photolytic release of caged effector molecules.
Article
Many technological advancements of the past decade have contributed to improvements in the photon efficiency of the confocal laser scanning microscope (CLSM). The resolution of images from the new generation of CLSMs is approaching that achieved by the microscope itself because of continued development in digital imaging methods, laser technology and the availability of brighter and more photostable fluorescent probes. Such advances have made possible novel experimental approaches for multiple label fluorescence, live cell imaging and multidimensional microscopy.
Volumetric display with dust as the participating medium, Feb. 14
  • K And Han
PERLIN, K., AND HAN, J., 2006. Volumetric display with dust as the participating medium, Feb. 14. US Patent 6,997,558.
A head-mounted three dimensional display
  • I E Sutherland
SUTHERLAND, I. E. 1968. A head-mounted three dimensional display. In Proceedings of the December 9-11, 1968, Fall Joint Computer Conference, Part I, ACM, New York, NY, USA, AFIPS '68 (Fall, part I), 757-764.
Tunnel ionization of complex atoms and of atomic ions in an alternating electromagnetic field
  • M V Delone
  • N B And
AMMOSOV, M. V., DELONE, N. B., AND KRAINOV, V. P. 1986. Tunnel ionization of complex atoms and of atomic ions in an alternating electromagnetic field. Soviet Physics-JETP 64, 6, 1191-1194.
Volumetric display with dust as the participating medium
  • K Perlin
  • J Han
PERLIN, K., AND HAN, J., 2006. Volumetric display with dust as the participating medium, Feb. 14. US Patent 6,997,558.