Francisco Renero

National Institute of Astrophysics, Optics and Electronics | INAOE · Coordinación de Óptica

Background: Thermoregulation is a complex autonomic process to keep or to dissipate heat in the human body. Methods: In this work, by means of the thermogram of the plantar skin, the thermoregulation of healthy individuals, overweight–obese, and diabetic is discussed. Results: The thermograms of the plantar skin, for the healthy individuals, are: (...

Background: One of the complications of the diabetes mellitus is the amputation of the lower limbs. This complication may be developed after an insidious ulcer, that may be raised by the peripheral neuropathy or the ischaemic limb, and that the ulcer get infected. That is, to develop an ulcer, in the diabetic patient, three factors should be taken...

This paper reports the novel design of a touch mode capacitive pressure sensor (TMCPS) system with a wireless approach for a full-range continuous monitoring of ventricular pressure. The system consists of two modules: an implantable set and an external reading device. The implantable set, restricted to a 2x2 cm2 area, consists of a TMCPS array con...

We propose a novel design of micro-optical devices based on multi-aperture compound insect eyes, which transfer a point-to-point multichannel free space signal combined with a diffraction grating. The system is inspired in the refractive superposition compound eyes configuration known as Gabor superlens (GSL) using microlens arrays. A switching fun...

In this work, statistical formulae, with depend on anthropometric measurement and the age, are used to estimate the weight of the lower limb of 20 young, healthy, adults. Then, four clinical characteristics, the body mass index, the blood volume, basal metabolic rate and skin surface, also based on statistical formulae, are estimated for this sampl...

Breast thermography may be used for the early detection of breast diseases in women younger than 50 years. Performed breast thermography on a woman in her 20s, revealing an average temperature difference of about 1°C. Ultrasound imaging further identified a simple cyst and enlarged, vascularized lymph nodes in both axillae.

This work presents the design, fabrication, and rigorous validation of a flexible, wireless, capacitive pressure sensor for the full-range continuous monitoring of ventricular pressure. The proposed system consists of an implantable set and an external readout device; both modules were designed to form an RCL resonant circuit for passive, wireless...

In this study, we explored non-contact pulse wave measurements from the extremities, particularly the soles, and examined their differences. Two experiments were conducted. First, we identified the optimal method for capturing pulse waves and discovered that the peak intensity of the green signal was the most effective. Then, we analyzed the tempor...

The thermography of the plantar skin has been used to assess the feet complications of the patient with Type 2 Diabetes Mellitus, T2DM,1-3 particularly, for the follow up of the treatments of the Peripheral Artery Diseases, PAD.4 Furthermore, the photoplethysmogram (PPG), may be used to observe the blood flow on the toes.5 Then, as a complement to...

The purpose of this research was to determine if respiratory muscle (RM) training, through the MRFit protocol, increases the maximum oxygen consumption and the anaerobic threshold in a group of young professional swimmers, to improve their sports performance. Eleven professional swimmers (7 women and 4 men) between 13 and 17 years old were recruite...

In this Letter, a Gabor superlens with variable focus is presented. This configuration uses tunable liquid lenses in the third microlens array of the Gabor superlens. By applying voltage, the radius of curvature of the micro-tunable doublet arrays changes, and the Gabor conditions are fulfilled at different focal planes. As a consequence, the magni...

The stereoscopic vision is widely used to acquire depth information, distances between objects, as well as obstacle detection. In this work, a method that reduces the amount of data to obtain depth information for a specific scenery is proposed. The method reduces a 640x480 size image to a 3x3 matrix, simplifying the instructions and decision makin...

In this paper, an alternative strategy for the design of a bidirectional inductive power transfer (IPT) module, intended for the continuous monitoring of cardiac pressure, is presented. This new integrated implantable medical device (IMD) was designed including a precise ventricular pressure sensor, where the available implanting room is restricted...

In this paper, the design, manufacturing process and testing of a device able to detect obstacles at head level is presented. The device's functionality is based on emission and detection of infrared light and the tactile stimulus. The design was performed in order to detect objects, from the head and up to 150 cm away. The fabrication was done usi...

The advances in infrared thermography during recent years have opened new possibilities for its use in medical diagnosis. The detection of complications related to diabetic foot is one of the many uses of this technology. This paper presents a new public plantar thermogram database composed of 334 plantar thermograms from 122 diabetic subjects and...

This work presents a novel design of a bidirectional Inductive Power Transfer (IPT) system capable of continuous monitoring of cardiac pressure. The proposed system results from a robust electromagnetic coupling between an external reading coil and an implanted two-level (3D approach) inductor array. In this design, each coupling module follows a 1...

The symmetry of the human face plays an important role in the activities of the individual's daily life. On the other hand, the asymmetry of the face can be synonymous with diseases in the individual, some manifest at rest and others in movement. In this work we quantify four of the movements of the human face. The quantified movements are lifting...

This paper reports the novel design of a touch mode capacitive pressure sensor (TMCPS) system with a wireless approach for a full-range continuous monitoring of ventricular pressure. The system consists of two modules: an implantable set and an external reading device. The implantable set, restricted to a 2 × 2 cm2 area, consists of a TMCPS array c...

By defining a midline and selecting six pairs of the landmarks of the human face on digital photographs, we extracted the symmetry of the human face by means of digital techniques. As a first approach to the symmetry of the human face, the distances and the tilts from the midline, between similar landmarks, were computed and averaged, respectively....

This paper presents a novel approach to characterize and identify patterns of temperature in thermographic images of the human foot plant in support of early diagnosis and follow-up of diabetic patients. Composed feature vectors based on 3D morphological pattern spectrum (pecstrum) and relative position, allow the system to quantitatively character...

Early detection of symptoms related to ulceration risk in patients with diabetes mellitus can prevent future complications. In recent years thermography has been a response to this problem. Thermography is presented as a rapid, non-invasive and non-contact technique for detecting potential temperature patterns that may have complications in the fut...

The uni-pupil of the gecko eye (Tarentola chazaliae), in maximum illumination condition, is transformed into four small pupils. Since, the spectral range of gecko is from UV to VIS, its eye can be considered as a multiple focus optics system. Optical simulation are discussed on this presentation.

A methodology is proposed to determine the positions of the characteristic facial points. The method is based on the Point Distribution Model, which estimates the most likely positions points. The search is refined with a discriminator, acting locally, around each point of the model; this discriminant model was achieved by training a Support Vector...

Optical interconnection at high-speed and large-capacity transmission of data has the advantage of conveying information at large bandwidths in free space with less crosstalk than electronics. We propose here the design of micro-optical devices based in the multi-aperture compound insect eyes that will transfer a signal as a freespace multichannel...

An ultrathin objective with the configuration of an artificial apposition compound eye was designed in order to obtain a miniaturized camera. The optical design was based in a nonconventional multi aperture configuration of a diurnal insect eye that uses ommatidia as individual units. An aspherical cylindrical micro doublet (CMD), obtained by ALSIE...

We present the design of a non-conventional optical system that uses cylindrical micro-doublets (CMD), integrated in an artificial apposition compound eye configuration (AACE). We show some designs of an ultra-thin objective inspired in fly eyes. These designs can give options to create new technologies that will process information in a different...

We present the optical design of an ultra-thin non-conventional objective lens (UTOL), based on the concept of superposition compound eye that some insects and arthropods have. One of the features of the UTOL is the capability to improve image quality by using an array of micro-tunable lens. Lens parameters, design and simulation techniques are des...

Multi-aperture optics based on insects and arthropods eyes, is an interesting topic related to the development of miniaturized non-conventional optical designs. This novel concept has been used in image formation devices that offer many benefits in miniaturization and in improving certain optical characteristics, like a widef field of view. Energy...

a b s t r a c t A scheme to study fabrication tolerances of optical components and systems is presented. By solving a set of non-linear inequalities an optimal set of lens parameters is found. Then, by selecting another, but strict, set of boundaries to the non-linear inequalities system, a new set of lens parameters is found. The fabrication toler...

A two-dimensional optical micro-scanner, which main components are two mobile flat and a concave micro-mirrors, is designed such that, all optical components can be fabricated on the same substratum. The optical parameters, which physical dimensions are between 50 and 500 μm, are obtained within the geometrical optics. The optical performance is ev...

Derechos Reservados El autor otorga al INAOE el permiso de reproducir y distribuir copias de esta tesis en su totalidad o en partes. Desigualdades No-lineales y lineales en ALSIE Francisco-J Renero-C Óptica INAOE paco@inaoep.mx Resumen Compactando las distancias focales, efectiva y posterior, de un triplete clásico muestro detalles numéricos de las...

The radio spectroscopy has became a fundamental tool to study astronomical objets at the microwave band. Therefore, the design and construction of instruments with high spectral resolution, low power consumption and compact size for easy handle and transport are necessary. Here we present the design and the tests of an acousto-optical spectrometer...

A mobile (electrostatic) flat mirror is designed to bend visible light, and can be fabricated on crystalline silicon by means of photolithography and humid etching. Using the CoventorWareTM software we carry out a simulation of the fabrication process as well as the movement versus voltage of the mobile (electrostatic) flat mirror, which dimensions...

This paper presents a study of the optical properties of amorphous hydrogenated silicon nitride ( a-Si3N4: H ) films under deposition temperature influence. The films were deposited by low-frequency plasma-enhanced chemical vapor deposition at temperatures of 200, 300, and 400 degrees C and 0.6-Torr pressure. The mixture gases were silane ( SiH4 ),...

In this paper the optical properties of CdSe thin films obtained by spray pyrolisis are presented. The films are prepared by Sodium Selenosulphate (Na2SSeO3) and Cadmium Chloride (CdC12) mixing in aqueous environment. Optical parameters of the films (refractive index, absorption coefficient and optical bangap) were calculated from transmittance spe...

In this paper the optical properties of CdSe thin films obtained by spray pyrolisis are presented. The films are prepared by Sodium Selenosulphate (Na2SSeO3) and Cadmium Chloride (CdCl2) mixing in aqueous environment. Optical parameters of the films (refractive index, absorption coefficient and optical bangap) were calculated from transmittance spe...

Presentamos el diseño de fabricación de una superficie cónica con k = ¡6:5. En un sustrato de silicio monocristalino, tomando como base la técnica de grabado anisotropico con KOH. La superficie cónica es aproximada mediante ventanas esféricas. Comparaciones entre diámetro y separación de las ventanas esféricas, así como los parámetros que rigen la...

A fabrication design of a conic surface (k = -6.5), in monocrystalline silicon substrate and based on anisotropic etching with KOH, is presented. The conical surface is approximated by means of spherical windows; comparisons between diameter and separation of the spherical windows, as well as the parameters that govern the selection are discussed.

Design of afocal systems, for 1.5μm wavelength, are presented. They are based on the Galilean Telescope, composed of a silicon negative microlens (305 μm diameter) and a positive lens chosen between 10 different materials, according to the best optical performance. The spherical aberration and the Strehl ratio are used to compute the best optical p...

Design of afocal systems, for 1.5 mu m wavelength, are presented. They are based on the Galilean Telescope, composed of a silicon negative microlens (305 mu m diameter) and a positive lens chosen between 10 different materials, according to the best optical performance. The spherical aberration and the Strehl ratio are used to compute the best opti...

The shape and diffraction pattern of a liquid crystal display (LCD) pixel used in a point-diffraction interferometer is qualitatively evaluated using the experimental diffraction patterns of computer-generated apertures. The diffraction patterns for apertures with contours between a circle and a square were numerically plotted from analytical expre...

Optical, structural and electric properties of (a-(Si90Ge10)1-yBy:H) thin film alloys, deposited by low frequency plasma enhanced chemical vapour deposition, are presented. The chemical bonding structure has been studied by IR spectroscopy, while the composition was investigated by Raman spectroscopy. A discussion about boron doping effects, in the...

Amorphous silicon germanium (a-Si1-xGex) thin films are prepared by low-frequency plasma-enhanced chemical vapor deposition (LF PECVD) on glass substrates, from SiH4+GeF4 and SiH4+GeH4. These films are deposited under capacitive discharge during 60 min, at a frequency of 110 kHz, substrate temperature of 300°C, pressure of 0.6 Torr, and power of 35...

Derechos Reservados El autor otorga al INAOE el permiso de reproducir y distribuir copias de este reporte técnico en su totalidad o en partes.

In this paper, we present one method of numeric analysis for the star test with MatLab (ANPEM), applied to reflecting telescope. ANPEM finds the difference between centers of the images of the annulus obtained with a Newtonian telescope and a Ritchey Chretiene telescope with 14 and 211 cm of diameter respectively. ANPEM allows to identify quantitat...

In this paper, we present one method of numeric analysis for the star test with MatLab (ANPEM), applied to reflecting telescope. ANPEM finds the difference between centers of the images of the annulus obtained with a Newtonian telescope and a Ritchey Chretiêne telescope with 14 and 211 cm of diameter respectively. ANPEM allows to identify quantitat...

In this paper, we present one method of numeric analysis for the star test with MatLab (ANPEM), applied to reflecting telescope. ANPEM finds the difference between centers of the images of the annulus obtained with a Newtonian telescope and a Ritchey Chretiene telescope with 14 and 211 cm of diameter respectively. ANPEM allows to identify quantitat...

Derechos Reservados El autor otorga al INAOE el permiso de reproducir y distribuir copias de este reporte técnico en su totalidad o en partes.

An optoelectronic integrated device that carries out digital optical functions is designed in silicon technology. The device achieves the NOR gate, which has input and output optical signals, and is designed to detect and emit a 600-nm-wavelength light. The active detection area is 1 mm2, and it can achieve frequencies of the order of megahertz.

In this work we present some results obtained on the design and fabrication of Schottky barrier photodetector. The derive is suitable for operation in the IR zone of the electromagnetic spectrum. This device is fabricated by using a Silicon-Germanium amorphous alloy on p-type crystalline silicon. The device operates in the range 1.0-4.5 micrometers...

Using the shadow casting technique for paralell processing, design and implementation of a hybrid flip-flop RS are presented, which employ the polarization tecnique as the input codification, a prism to reflect and transmit polarized light. An electronics circuit is used for the photoelectric conmutation and for the time delay. Implementing sequenc...

The evaluation of the optical performance of optical systems by means of the diffraction patterns, bidimensional input objects com- posed of several object points, etc. consumes a huge amount of com- puting time. Furthermore, multiple-purpose optical systems that use the Fourier and image planes for different applications require evaluation and opt...

Astronomers use telescopes to study the universe in the different spectrum regions. The dimensions of telescopes, to research in the millimeter region, are too big. Thus, fabrication of such instruments is a challenge work. The “Gran Telescopio Milimétrico (Large Millimeter Telescope, which will be called LMT) is a Cassegrain Telescope, which diame...

Although the optical performance of multiple imaging (MI) lens systems, composed of conventional lenses and radial-GRIN lens arrays, can be obtained by correcting the optical aberrations. An optimization technique considering wave optics is desirable, when the dimension of component lenses becomes so small and diffraction effects cannot be neglecte...

Reflective block optical systems have been used to achieve tasks realized by lens systems, but offering compactness and flexibility to construct optical computing systems. Thus, the reflective optical systems have to achieve optimal optical performance. In this work, we use the procedure of ALSIE (Automatic Lens Design By Solving Inequalities, T. S...

The ALSIE (Automatic Lens Design By Solving Inequalities, T. Suzuki, et al., J. Opt. Soc. Am., 56, 677, 1966) algorithm is a powerful lens design procedure for the optimization of conventional and unconventional lens systems. However, a problem of the ALSIE algorithm is the selection of an adequate set of boundaries to the performance functions. In...

Use of an aspherical surface in the design of a lens system for one-to-many optical-interconnects (OTM-OI), composed of a doublet lens and a gradient-index (GRIN) lens array has been investigated. Applying the procedure of ALSIE (Automatic Lens design by Solving InEqualities), the off-axis lens systems, which feature the optical performance of the...