Simon Thibault

• Université Laval

We propose a novel far-field characterization method that provides a simple and fast measurement of three-dimensional (3D) light field display (LFD) performance. Using both experimental and theoretical approaches, we quantitatively compare far-field and near-field optical performances. Through the analysis of an integral imaging-based 3D LFD protot...

Astronomy and Space Domain Awareness are limited by the size of available telescope optics, the cost for which scales steeply due to the exquisitely ground and polished primary mirrors, typically made of glass or other lightweight substrates. Liquid mirrors (LMs) may break this unfavorable cost scaling. When rotated at a constant angular velocity,...

Our study presents recent progress in modelling and performing lens optical design with metasurfaces. We developed semi-analytical models that recover the output phase, polarization, dispersion and group delay of various nanostructures. This enables the mixing of different nanostructures to obtain a target dispersion profile an interesting applica...

Tool use and language are highly refined human abilities which may show neural commonalities due to their potential reciprocal interaction during evolution. Recent work provided evidence for shared neural resources between tool use and syntax. However, whether activity within the tool-use network also contributes to semantic neural representations...

This Feature Issue of Optics Express is organized in conjunction with the 2023 Optica conference on 3D Image Acquisition and Display: Technology, Perception and Applications which was held from 14 to 17²⁰⁸ of August as part of the 2023 Imaging and Applied Optics Congress in Boston, Massachusetts, United States. This Feature Issue presents 27 articl...

Improved miniaturization capabilities for complex fisheye camera systems have recently led to the introduction of many compact 360-degree cameras on the consumer technology market. Designed primarily for recreational photography, several manufacturers have decided to allow users access to raw imagery for further editing flexibility, thereby offerin...

Astronomy and Space Domain Awareness are limited by the size of available telescope optics, the cost for which scales steeply due to the exquisitely ground and polished primary mirrors, typically made of glass or other light-weight substrates. Liquid mirrors (LMs) may break this unfavorable cost scaling. When rotated at a constant angular velocity,...

The Near-InfraRed Planet Searcher or NIRPS is a precision radial velocity spectrograph developed through collaborative efforts among laboratories in Switzerland, Canada, Brazil, France, Portugal and Spain. NIRPS extends to the 0.98-1.8 $\mu$m domain of the pioneering HARPS instrument at the La Silla 3.6-m telescope in Chile and it has achieved unpa...

We developed semi-analytical models to efficiently and rapidly obtain the propagation characteristics of square nanopillar and nanoring meta-atoms. We show that such analytical models can predict the output phase profile and chromatic behavior of a metasurface composed of various meta-atoms. We found that said models are accurate enough so that an...

The elemental images (EIs) generation of complex real-world scenes can be challenging for conventional integral imaging (InIm) capture techniques since the pseudoscopic effect, characterized by a depth inversion of the reconstructed 3D scene, occurs in this process. To address this problem, we present in this paper a new approach using a custom neu...

We propose a method to design the exact phase profile of at least one metasurface in a stigmatic singlet that can be made to implement a desired ray mapping. Following the generalized vector law of refraction and Fermat’s principle, we can obtain exact solutions for the required lens shape and phase profile of a phase gradient metasurface to respec...

The two-planet transiting system LHS 1140 has been extensively observed since its discovery in 2017, notably with Spitzer, HST, TESS, and ESPRESSO, placing strong constraints on the parameters of the M4.5 host star and its small temperate exoplanets, LHS 1140 b and c. Here, we reanalyze the ESPRESSO observations of LHS 1140 with the novel line-by-l...

As more and more cameras are dedicated to machine perception applications, we present an end-to-end vision system simulation pipeline to redefine key performance indicators when cameras are used alongside machine learning algorithms.

Using wide-angle systems’ distortion optimization for improved monocular depth estimation as a case study, we investigate the scope, benefits, and limitations of current end-to-end optical design practices in a context of machine perception. Full-text article not available; see video presentation

We report the detailed investigation of the capability of an electrically tunable liquid crystal lens (TLCL) to dynamically generate various wavefront shapes. The TLCL operates in the modal-control mode with a peripheral circular electrode divided into eight individually controlled segments. This segmentation allows producing a rather rich set of i...

Herein it is presented a new vector diffraction integral capable to compute the diffraction patterns for aspheric and freeform wavefronts, with different pupil shapes, and different polarization states. The aforementioned vector diffraction integral is based on the energy conservation theorem, the far field approximation, and the angular spectrum r...

A better understanding of the radiative transfer of solar visible light within sea ice is crucial to study the Arctic energy balance and marine ecosystems. In this work, we showcase the utilization of a compact, consumer-grade 360-degree camera for measuring the in-ice spectral angular radiance distribution. This novel technique allows for the inst...

Improved miniaturization capabilities for complex fisheye camera systems have recently led to the introduction of many compact 360-degree cameras on the consumer technology market. Designed primarily for recreative photography, several manufacturers have decided to allow users access to raw imagery for further editing flexibility, thereby offering...

This Feature Issue of Optics Express is organized in conjunction with the 2022 Optica conference on 3D Image Acquisition and Display: Technology, Perception and Applications which was held in hybrid format from 11 to 15, July 2022 as part of the Imaging and Applied Optics Congress and Optical Sensors and Sensing Congress 2022 in Vancouver, Canada....

This paper describes the process through which stray light analysis should be performed in optical systems involving image slicers. It details how scattering models should be used depending on how the image slicer assembly will be fabricated. This work describes how to determine all ray paths, compute cross-talk on the pupil mirrors due to scatteri...

We developed a quantum dot volumetric display based on two-photon absorption. We have shown that we are able to form a voxel using an NIR laser focused in the volumetric display.

We present a wide-angle design simulation using simplified, computationally efficient PSF models which maintain accurate neural network performance predictions. By integrating it into an end-to-end differentiable pipeline, we optimize the distortion for improved depth estimation.

We propose a new method for integrating metasurfaces in optical design using semi-analytical modeling of dielectric nanostructures. The latter computes the output phase of an electric field incident on the metasurface, allowing their use with ray-tracing software. This tool provides a method to use metasurfaces in optical systems while using built-...

Most camera lens systems are designed in isolation, separately from downstream computer vision methods. Recently, joint optimization approaches that design lenses alongside other components of the image acquisition and processing pipeline -- notably, downstream neural networks -- have achieved improved imaging quality or better performance on visio...

Data-driven methods to assist lens design have recently begun to emerge; in particular, under the form of lens design extrapolation to find starting points (lenses and freeform reflective system). I proposed a trip over the years to better understand why the AI have been applied first to the starting point problems and where we are going in the fut...

We propose a new method for integrating metasurfaces in optical design using semi-analytical modelling of dielectric nanostructures. The latter computes the output phase of an electric field incident on the metasurface, allowing their use with ray-tracing software. This tool provides a method to use metasurfaces in optical systems while using built...

The Gemini Infrared Multi-Object Spectrograph (GIRMOS) is an adaptive optics-fed multi-object integral field spectrograph with a parallel imaging capability. The instrument is composed of four separate but identical spectrographs, giving it the ability to observe four objects simultaneously. Each slicer-based integral field spectrograph offers capa...

Image slicers are now common equipment in integral field spectrographs (IFSes) to detect and analyze distant galaxies and extra-solar planets. However, tilted surfaces cause vignetting between adjacent slices and off-axis optical aberrations. In this paper, we explore how the flexibility of metasurfaces can be used by adjusting the surface phases o...

In recent years, GRENOUILLE has emerged as a relatively simple technique to fully characterize the electric field of an ultrashort laser pulse in a single shot. It does so by spatially mapping the delays on the transverse spatial coordinate and by mapping the frequencies on the angular coordinate of the orthogonal direction. Because of this spatial...

NIRPS (Near Infra-Red Planet Searcher) is an AO-assisted and fiber-fed spectrograph for high precision radial velocity measurements in the YJH-bands. NIRPS also has the specificity to be an SCAO assisted instrument, enabling the use of few-mode fibers for the first time. This choice offers an excellent trade-off by allowing to design a compact cryo...

Allowing natural scenes as well as maximizing field of view (FoV) can benefit from the minimization of distortion for the wide-angle camera. The wide-angle camera utilizing freeform surfaces for mitigating distortions, either barrel distortion or pincushion distortion, is therefore of interest. In this paper, the designs of using all-aspherical sur...

We present a new formalism, based on Richards–Wolf theory, to rigorously model nonparaxial focusing of radially polarized electromagnetic beams with freeform wavefront. The beams can be expressed in terms of Zernike polynomials. Our approach is validated by comparing known results obtained by Richards–Wolf theory. Our integral representation is com...

We proposed a model to estimate surface topography and transition edge width in diamond-turned non-circular compound freeform optics featuring right angle transitions. The method serves as comparison basis between both full and split radius tools and takes into consideration basic cutting and tooling parameters relevant to a raster tool path, along...

Tool use and language are two highly refined human abilities which may have co-evolved, thus resulting in neural commonalities. We recently provided evidence for shared neural resources between tool use and syntax. However, the debate is still open on whether semantics and phonology also recruit neurofunctional supplies common to tool use. Here we...

Tool use and language are highly refined human abilities which may show neural commonalitiesdue to their potential reciprocal interaction during evolution . Recent work provided evidence for shared neural resources between tool use and syntax. However, whether activity within the tool-use network also contributes to semantic neural representations...

Lens design extrapolation (LDE) is a data-driven approach to optical design that aims to generate new optical systems inspired by reference designs. Here, we build on a deep learning-enabled LDE framework with the aim of generating a significant variety of microscope objective lenses (MOLs) that are similar in structure to the reference MOLs, but w...

It is generally difficult to define the duration of few-cycle laser pulses in the presence of spatiotemporal coupling. The pulse temporal width can indeed vary locally across the pulse front and spatially varying delays can complicate the definition of the temporal pulse length over the whole pulse front. However, the simple formalism of the global...

We developed a simulation pipeline of realistic wide-angle systems and compare the relative influence of optical characteristics used for design optimization (distortion, PSF) on single-image depth estimation accuracy using neural networks.

We developed a versatile experimental setup able to characterize the optical performance of different 3D display designs based on far-field (spot size, lateral color) and near-field (contrast, spatial resolution, MTF) measurements.

A system to study the evolution of snow density is presented here with an emphasis on the system itself and on the efforts to make a robust system for harsh environments. The metric to deduce the density of the snow is the measurement of the concentration of ambient air oxygen using a tunable diode laser spectroscopy technique: the first harmonic p...

Autonomous and cabled platforms are revolutionizing our understanding of ocean systems by providing 4D monitoring of the water column, thus going beyond the reach of ship‐based surveys and increasing the depth of remotely sensed observations. However, very few commercially available sensors for such platforms are capable of monitoring large particu...

Common basis for language and tool use Tool use and language are hallmarks of human evolution. Because of the similarity between the motor processes for tool use and those supporting language, it has been hypothesized that syntax and tool use may share brain resources. Using functional magnetic resonance imaging and multivariate pattern analysis, T...

We propose a method to evaluate the optical propagation properties of a dielectric non-resonant metasurface composed of rectangular nanofins. Our approach is based on a semi-analytical assessment of the effective indices to perform guided vectorial propagation inside the nanostructure. The proposed model is an extension of the commonly used Panchar...

Image slicers are now standard equipment in the field of astronomical instrumentation. They are widely used in most integral field spectrographs (IFSes) to detect and analyze distant galaxies or extra-solar planets. Although those are notoriously difficult to manufacture due to their multiple small tilted surfaces, equipment such as that of AOFI (A...

We present a study of the diffraction pattern according to Richards–Wolf for an aplanatic and stigmatic singlet based on an exact analytical equation. We are able to put emphasis on the maximum diameter and illumination pattern, which are the two parameters that influence the diffraction pattern and how to compute it. Designs of low- and high-NA ap...

The 30th meeting of the Society for the Neural Control of Movement (NCM) was originally scheduled to take place in Dubrovnik, Croatia, in April of 2020. Due to the COVID-19 pandemic, the in-person meeting was canceled and replaced by a virtual symposium showcasing the work of the society’s 2020 scholarship winners. By the spring of 2021 (April 20th...