Session Index

The holographic optical engine that is composed of a spatial light modulator (SLM), image sensors, relay optics, and a control computer performs an optimization of a computer-generated hologram (CGH) in an optical system. The CGH optimized before or during laser processing generates two- and three-dimensional focusing spots with an automatic compensation of static imperfections and dynamic changes in the optical system, therefore the holographic laser processing is performed with high stability, high-throughput, and high usability.

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We proposed several methods to improve the image quality in a diffractive additive manufacturing (DAM) system in which a sequence of diffractive optical elements (DOEs) encoding slice images of 3D objects produce volumetric images for polymerizing photosensitive resins. Adding a linear phase to the DOE function to shift the diffraction images away from the reflection of the SLM window, stacking multiple diffraction images of random phases to smoothen the speckle effect, and varying the intensity of diffraction image to increase the longitudinal continuousness, we successfully achieved a DAM system with high efficiency, high resolution, fast working speed and good continuity.

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In recent years, digital holographic microscopy has been well-developed. It gets the advantages of high-speed phase imaging, quantitative phase imaging, and digital focusing without losing image quality. However, current commercial holographic microscopes are too bulky and expensive. Therefore, this paper proposed a volume holographic optical waveguide element combined with a digital holographic microscope to form a volume holographic lens-less digital holographic microscope. In the experiment, we successfully minimized the Lens-less Fourier Transform Digital Holographic Microscope, which has the advantages of high NA, minimizable body, and optical zoom. Furthermore, it can switch magnification without changing the object distance.

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In this study, we use MATLAB to model a plano-convex spherical lens for the microwave band which was fabricated with photopolymerization additive manufacturing technology. The results show that when the resolution of the printer meets the conditions, we can simulate the lens model by determining the lens focal length and curvature radius with MATLAB, and import the simulated model into the additive manufacturing software for editing. Finally, a lens with a radius of 50mm was successfully printed, and the flatness of the lens at wavelength of 2.85cm can also reach the high standard of λ/50.

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A developed deep learning based computer-generated holography (DeepCGH) can real-time stimulate neurons; however, the computation time as growing the number of input layers is increased and arbitrary 3D micropatterned cannot be reconstructed. Herein, a digital propagation matrix (DPM) containing the depth information of customized micropatterns is intergraded into DeepCGH to generate arbitrary 3D micropatterns and shorten the computation time. As a result, the DeepCGH with DPM could timely generate the customized micropatterns within a 300-μm volume with high accuracy. Furthermore, the DeepCGH hologram is rapidly displayed on spatial light modulator.

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In this study, a misalignment measurement method was proposed which based on grating-type heterodyne interferometry. The dislocation between two parallel gratings can be obtained and the optimum dislocation between them can be within 0.1% under the displacement of 100 µm.

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In this paper, the respective coherence properties of laser and sLED are measured
and the extent discussions are made to study how they affect the speckle noise in the
reconstructed images from a computer generated hologram. It can be seen from the results that
temporal coherence and speckle are positively correlated, but not proportional. This work
paves the way to compact and dynamical holographic displays free of speckle noise.

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Near-eye display systems based on lightguide structure will be presented in this talk.
Volume holographic optical elements (VHOEs) are generated and are attached on the
lightguide for images in-coupling and out-coupling in a near-eye display system. Different
VHOEs are designed and fabricated for two different image sources. A full-color display with
FOV of 30° is achievable with a planar display image. In addition, a monochromatic display
with FOV of 23° is presented when using computer-generated hologram (CGH) as image
source.

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By using a Fresnel biprism, the object and reference beam in digital holographic microscopy (DHM) could be easily separated at a small angle and propagate through a common path. The common DHM system we demonstrated is highly compact and able to minimize the influence of environmental fluctuation.

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We present a deep leaning-assisted three-dimensional segmentation method with holographic tomography and apply it to assess SH-SY5Y cell morphology. In the experimental results, the proposed method performs high speed and high accuracy in three-dimensional segmentation of the cells.

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An azobenzene holographic material based on the {[4-(dimethylamino) phenyl] diazenyl} benzoic acid (Methyl red) as a photo-responsive unit is synthesized. The surface relief grating is fabricated by 532 nm DPSS laser with a total power intensity of 200 mW/cm2. About 1500 nm depth of grating was fabricated on a film with thickness of 860 nm. Its diffraction efficiency as a function of time is demonstrated as well.

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A homemade PQ/PMMA VBG is utilized to feedback a 650 nm laser diode. Single longitudinal mode is achieved. By adding a twist nematic liquid crystal cell in the laser cavity serving as the phase modulator, the single mode laser output frequency can be tuned exceed 19 GHz.

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Since the evolution of artificial neural networks nowadays, computational lensless imaging had been making headway. However, generative models for scene reconstruction inherit challenge owing to the ill-posed property of inverse system, which superior results were obtained under constrained conditions. In this work, we proposed a deep neural network based lensless imaging system by optimizing perceptual loss exclusively to reconstruct scenes conforming human preference with end-to-end training. In our experiment, the purposed method could attain favorable quality, where the score achieved 0.15 by LPIPS merit at best.

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Instead of traditional image models, which accompany various prior conditions and feature engineering, in recent years, data-driven deep learning network models have gradually become attractive. Based on a lensless configuration with ordinary white light (completely noncoherent), a coded mask (or diffuser) as an example to modulate the light field, the CMOS sensor measures the intermediate image, we employed the convolutional neural network (CNN) architecture to reconstruct the readily uninterpretable signal. In addition to the reconstruction, we also conducted the face recognition as the vision task. Practical implications through such unconventional optics will be expected if pattern recognition, rather than relying mostly on human recognizable fidelity as it does in conventional imaging system, become more directly linked to the hidden or incomplete optical fields. More possibilities will be addressed during the conference presentation

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Real-time fall detection via deep learning is usually a challenge on embedded system due to limited computing power. In this work, we apply attention transfer to reduce the computational complexity and optimize memory usage. The proposed method achieved 98.06% testing accuracy on a real-time multi-view fall detection system.

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We proposed a spatial-modulate method to recover missing data in depth images. Depth cameras often fail to get depth data due to shinny and absorbing surfaces. Additionally, depth image inpainting using deep learning methods have compromised abilities to noise. These advance techniques often fail to provide correct depth data due to the influence of noise. To address both issues, we iteratively applied several low-pass filters to recover the missing data. We evaluated our method using depth images which were manually added large noise and defected area. The results indicate the high accuracy, precision, and anti-noise ability of our approach.

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Conventional calculation of performance based on M/# assumes the diffraction efficiency as a simple function of the material thickness. It ignores the three-dimensional distribution of refractive index, which contributes to different diffraction efficiency, and always leads to over-evaluation of the storage capacity. Therefore, we proposed an efficiency coefficient to calculate the diffraction efficiency per refractive index consumption

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A color-mixing light source was proposed that could measure the multi-wavelength signals in a time equal to that of a single wavelength. The three-parameter sine wave fitting method was used to analyze the mixed signal, and the desired amplitudes of light source signals of various wavelengths could be obtained.

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In this work photoaligning properties of polymer films containing azobenzene moieties as side-chain were prepared and characterized by means of optical spectroscopy and light induced birefringence. The key point underlying our study is that the photoinduced command surface can be used to obtain controllable ordering for nematic liquid crystal (LC) cell assembly. First, we demonstrate all-optical, polarization dependent LC director reorientation at azobenzene-doped polymer surface. Then we present for the first time to our knowledge, the correlation between the intensity of the writing beam and the polar anchoring energy of the photoalignment, through the dynamics of photo-induced birefringence

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This study shows the analysis of a holographic screen. The screen consists of a lens phase and a linear grating. The simplified formula for FOV estimation and astigmatism analysis are described. The optical characteristics with different parameters are discussed. The error between Zemax simulation and the simplified astigmatism analysis formula is deficient.

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The current status of low-loss phase change materials for reconfigurable photonics is reviewed. Additionally new developed GeSb based phase- change materials are studied towards optoelectronic and photonic applications.

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A 2D fringe pattern is presented for phase-shifting projected fringe profilometry in the tele-centric system. The characteristics of the 2D pattern make it available to discern fringes for surfaces with low signal-to-noise ratios. Even though the inspected surface is projected with only one fringe, unwrapping can be performed without ambiguity.

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Nowadays, humans not only care about the denture quality but also the color of denture.
However, it is very difficult to reconstruct teeth of the exact color. So, we have invented a new
technology to accurately measure the color of dentures.

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Graphene based materials have a variety of excellent properties and applications due to its remarkable electrical conductivity, surface and thermal properties. In this paper, the imaging approach to estimate the physical properties of graphene-coated glass with respect to the change collected on the three-dimensional (3D) surface is proposed. The holographic system is employed for the optical thickness measurement of relevance in the analysis of 3D surface distribution. Numerical and experimental results are performed to determine the change in conductivity of coated graphene which can be directly measured by the 3D imaging of digital holographic microscopy.

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A multifocal confocal fluorescence microscopic system is designed and developed by incorporating photopolymer (PQ-PMMA) based volume holographic optical element in the illumination path for generating multifocal super Gaussian (SG) beam spots to reduce the scanning time.

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Anomaly detection, an important task for industrial manufacturing, is aimed to distinguish the rare defects from mass production. We proposed a semi-supervised learning model with generative adversarial network (GAN), where the network learned the latent representations through normal data only. For the purpose of anomaly determination, the threshold was determined by measuring the distances between normal data and abnormal data in the latent space. With preliminary experiment, 99% true positive rate (TPR) under 5% false positive rate (FPR) was achieved on a commercial cosmetic patch dataset.

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We demonstrate the geometric phase writing in a nematic liquid crystal cell by using photo-alignment technique with photopolymer of PAZO. The assembled LC cell can convert an incident circularly light beam into the contrary circularly polarized beam with modulated phase related to the direction of alignment caused from PAZO. Thus, with appropriate designed pattern, novel diffractive waveplate, which provides many unique photonic applications can be written in a LC cell directly. In this paper, we show the comprehensive simulation model to characterize geometric phase property of the LC cell and fabrication of a diffractive geometric phase grating using polarization holography.

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Volume holograms are known to provide high transmission efficiency, single diffracted order, and compact size. These properties have been utilized for a variety of applications. Volume holography with beam shaping can be utilized for high resolution imaging applications for biological samples. Here, we present an Airy light sheet fluorescence microscope (Airy-LSFM) that uses volume hologram as an Airy beam shaper. Our method is easy to implement and it can provide a larger field of view, deep penetration depth, and better optical sectional capability, which helps measure large biological samples. The imaging performance can be further improved by using deconvolution method.

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A fringe projection profilometer encounters the challenge of noise disturbance due to projection system. In a short depth of field scanning profilometer, a phase shifting method is proposed to increase two dimensional data and to improve the resolution of the scanning fringe projection profilometer.

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The diffraction efficiency of traditional holographic storage will decrease as the number of multiplexed pages increases. This research team proposes a set of holographic storage technology to improve the diffraction efficiency of single-point multiplexing when the number of multiplexing pages is limited. Thus, the storage density of holographic storage is improved.

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We combined the rainbow hologram and the depth-added computer-generated hologram to produce a computer-generated rainbow hologram (CGRH), which can display a three-dimensional color image.

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A phase unwrapping method using the error-controlled fringe projection scheme for phase-shifting projected fringe profilometry is presented. Most unwrapping methods can not cope with the problems caused by low signal-to-noise ratios. The presenting method can detect such kind of errors and recover the mistake.

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In this study, photomask positioning system by combing the diffraction-based interferometer and the heterodyne phase measurement was proposed. Since this method used heterodyne phase measurement, the positioning errors caused by ununiform film thickness on the wafer can also be avoided.

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In this study, we propose a deep learning-based segmentation approach for three-dimensional (3D) composite surface with specular and diffuse regions. The proposed U-net based segmentation has been examined for specular and diffuse images from composite objects. The experimental results show that the proposed method can realize absolute 3D surface measurement and automatic segmentation for 3D composite regions based on integrated coherent system.

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This study proposes a real-time imaging system, which uses an image sensor to capture retrieving light spot images of an absolute optical rotary encoder, converts the images into coding signals, and outputs corresponding coding angles. The research contribution could be applied to real-time verification of signals in the developing stage of absolute optical rotary encoders, so as to skip the complex steps for specific photodetector design and fabrication.

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The display quality of a binary computer-generated hologram (BCGH) is usually low because of the high loss of information in the binarization. Here we purpose a new method, simulated-annealing binary search (SABS) algorithm to produce high-quality BCGHs.

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In this research, two different interferometry results were used to calculate the thickness of the optical plate, the first was the spectrally resolved white light interferometry technique, and the second was the laser interferometry technique. The measured data was compared with the theoretical value using the MATLAB program to further obtain the thickness of the optical plate.

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We proposed and demonstrated a novel method of an incoherent digital holographic camera. The compact system designed for the incoherent digital holographic camera was contributed by a modified common path architecture in the camera imaging system. The three-dimensional human face object would be directly obtained in a single shot without a stable optical table environment.

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In this study, the optimal brewing water temperature and brewing time for the content
of theaflavin were found by analyzing the absorption spectrum of the black tea soup, the
brewing time of the tea leaves, and the temperature of the brewing water. The results show that
the optimal brewing temperature is 85 °C and the brewing time is 2 minutes, which has the
highest theaflavin content.

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In this paper, we will present our studies on the fabrication of holographic optical elements using photoresist S1813. The holographic elements are recorded by using two-beam interfering lithographic method on S1813 spin coated glass substrate so that it is possible to achieve high diffraction efficiency in micro-meter thick thin film due to the huge refractive index difference between polymer and air. We will present how to make high quality thin film for performing holographic recording on S1813 spin-coated glass and we will also demonstrate the fabrication of a holographic waveguide for AR applications

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In recent years, head-mounted displays have received growing attention and lots of applications are presented. To miniaturize the devices, diffractive waveguide devices are the best solutions. We investigated relief grating through the finite element method rather than the traditional rigorous coupled-wave analysis. The depth and the tilt angle of the slits are considered in different incident angles and show the ability to inhibit the −1 order.

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This paper proposes an optical system for measuring liquid concentration using phase-enhanced total-internal-reflection (TIR) interferometry. In the proposed system, liquid concentration can be determined by measuring the phase difference between the s- and p- polarized states of a beam totally reflected from a phase-enhanced TIR apparatus with a tested solution. The method produced the measurement resolution and sensitivity better than 0.4 mg/dl and 0.08 deg (dl/ mg),

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Acoustic camera visualize sound using microphone array in the space to acquire sound signal at different positions. With Huygens-Fresnel principle and Kirchhoff integral theorem, the acoustic field distribution in space and time can be reconstructed as well as the source location.

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Recently, almost all communication systems on the market use radio waves to transmit information, although there are also papers using visible light as the transmission medium. In light transmission, most published papers use laser light as the output, few papers use Micro LEDs as the output, and they only use a small number of light sources to transmit information by adjusting the frequency and amplitude. Therefore, we hope to design a new communication system with the characteristic of Micro LEDs being able to switch between on and off at a fast speed to provide 5G or even 6G communication.

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In this study, a surface profile measurement based on interferometry as well as polarization interferometry with polarization cameras was introduced. By analyzing the relationship between the density of interference fringes and the angle between the measurement surface and the reference surface, the surface profile measurement under the minimum number of interference fringes can be calculated. The measuring range of the system is 80 mm in diameter.

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In this study, a solar photovoltaic module recycling and sorting system based on thermal imaging machine vision was designed. The solar photovoltaic modules after thermal cracking were sorted through the combination of thermal imaging and mechanism control. The sorting accuracy for glass and silicon substrates are 90%.

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Materials exhibiting photo-induced birefringence are interested in many possible applications of optical information processing and storage. The PQ/PMMA, a kind of doped photopolymer consists of polarization-selectively absorbing PQ molecules dispersed in an amorphous PMMA polymer, and thus can undergo anisotropic photodissociation by linearly polarized light, resulting in photoinduced birefringence. In this article, we will discuss the effect of light-controlled photo-birefringence in PQ/PMMA photopolymers and discuss the correlation coefficients of the induced birefringence properties.

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FaceNet is a face recognition framework proposed by Google in 2015. Rapid advances in deep learning hardware, software, and technology enable the development of more face recognition techniques. The You Only Look Once (YOLO) is a fast deep learning object detection framework. Implementing the YOLO neural network in a face recognition algorithm should significantly improve the recognition speed. For this purpose, the feasibility of replacing multi-task cascaded convolutional networks (MTCNN) with YOLOv5 to detect human faces was explored. The results showed that YOLOv5 was very effective in detecting faces and reducing the recognition time, thus demonstrating a promising prospect.

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In this paper, we present the feasibility of using convolutional neural networks (CNNs) for information decryption in digital holography. We established a deterministic phase-encoded encryption system based on digital holography. The original image is made into an encrypted hologram and used as ciphertext. The CNN model can be trained by using the ciphertext and its corresponding original image. The trained CNN model is employed to predict the original image. Experimental results show that the trained CNN model can generate plaintext from ciphertext. According to the simulation results of this study, CNN is a feasible method for evaluating information security.

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YOLO (You Only Look Once) neural network is an object detection-like neural network roadmap algorithm implemented in darknet architecture, which has the advantages of light weight and high efficiency. This research is applied to the identification of the remaining parking spaces in the parking lot and the intelligent car search system. The results show that yolo can identify the position of the vehicle with accuracy of 99.72%.

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The overlay (OVL) measurement is an essential process control element of a scanner in advanced lithography. According to the report of the International Roadmap for Devices and System 2020, the OVL tolerance of a scanner decreases as the semiconductor process node advances. For example, the allowable OVL value is about 3.6 nm in the case of the dynamic random-access memory (DRAM) components, and the required OVL metrology precision must be as small as 10% of the allowable OVL value, i.e., 0.36nm. The diffraction-based measurement (DBO) was widely used as the technology node less than 20nm. The DBO metrology has overlapping targets, and the OVL value is determined by measuring an intensity unbalance in diffracted light. According to the DBO measurement principle, the measured OVL signal is an asymmetric diffraction signal generated by the measurement target, and a linear calculation model calculates the OVL value. However, since the wafer processing effect of the etching process and the chemical-mechanical polish (CMP) process caused the deformation of the measurement target profile, and then it will result in the OVL measurement error. Hence, in this paper, we proposed a robust and wafer-less measurement wavelength selection methodology based on the FDTD simulation for the measurement target with an asymmetric profile structure

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By applying optical scanning holography (OSH) to three-dimensional holographic microscopy, the twin image and the zeroth order light arose in conventional digital holography can be suppressed. In addition, the OSH can record an incoherent hologram, which makes the fluorescence holography possible.

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In this study, a commercial microwave transceiver system with a wavelength and frequency of 2.85 cm and 10.525 GHz was diagnosed. The characteristics of this system was tested, including the output waveform, the wavelength, the polarization state, the operational orientation of the transceiver. With the system, the Brewster's angle and Malus' law were verified. The diffraction intensity of metal-wired lattice structure was observed which can be used to confirm the interplanar spacing and evaluate the wavelength of the wave source. Considering the unique characteristics of microwave-matter interactions, the operation characteristics of microwave transceiver system should be known before advanced applications.

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The digital holographic microscope uses a lensless Fourier transform system combined with holographic optical elements[1]. Due to its light weight, small size and high resolution, various noises are still observed. This article focuses on "Analysis of observed noise and possible solutions for light guide elements and digital reconstruction processes".

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The volume holographic optical element (VHOE) functioned as micro-lens could be applied to the light field out-coupler of the near-eye display. In this paper, we propose an optical model of the micro-lens functioned VHOE, based on a 1-D analytical solution. The effects of image color distribution and viewing angle variation can be analyzed.

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In this study, we proposed the method to conceal the eye-track camera. The image of the user's eye propagates via the waveguide combiner. The aberration caused by the waveguide was analysed via ray-tracing method. Furthermore, we also discuss the method to compensate for the aberration and enhance the image quality.

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In this study, High-precision 3x3 polarization maintaining fiber coupler was made with fused biconical taper method. To control the pulling speed and temperature, the coupling ratio can be better than 31% for the three output ports and coupling ratio difference will be less than 3% between port 1 and port 3. In additions, the extinction ratio and excess loss can be reached to 20 dB and better than 0.7 dB.

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In this method, we derived the phase of the asymmetry intensities of interference signals and found that the phase caused by the overlay is proportional to the diffraction order. A high order diffraction light was used to enhance the overlay measurement signal. To demonstrate the feasibility, we compared the frequencies of the asymmetry intensity curve under different overlay values. The frequency of the asymmetry intensity of the second order diffraction signal was twice of that of the first order diffraction signal.

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We demonstrate the preparation of photopolymer glass films with good optical quality by sol-gel reaction. Samples with maximum diffraction efficiencies over 90% were produced. Using different angles when recording holograms shows that the samples can make different holographic diffraction elements for application in various systems. Finally, the high transmittance and low shrinkage were verified by spectrometer measurement and Bragg mismatch angle experiment.

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In recent years, the technology of image recognition has been popular and used in many applications, such as the real-time detection of animals for species conservation. In the study, we use the YOLO(You Only Look Once) neural network to recognize the deer in photos for estimating the amount of deer living in some region. By using the images of sika deer captured from videos for training YOLO neural nework to find sika deers accurately.The results show that YOLO can detect the sika deer in photos and videos in real time, which 95% accuracy can be achieved.

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Analyzing hyperspectral imaging (HSI) is a way to find out the material properties that are difficult to be observed with our naked eyes. This experiment was based on the hyperspectral sensor developed by imec. We used push-broom scanning to get the data of HSI. Our interface built by PyQt5 was able to display the camera image in real time and capture images with the one-dimensional motorized platform. After analyzing the deviation of stitched images, we concluded that the platform may have 10.3˚clockwise rotations relative to the camera.

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In this study, a novel phase shift interferometer with moving grating as the phase shifter was proposed. To demonstrate the feasibility of this method, the phase retardations between the S and P polarizations of a quarter-waveplate and a half-waveplate were measured. This method has the advantages of high accuracy and time saved.

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A binary encoding algorithm is presented for phase-shifting projected fringe profilometry. It does not require additional projections to identify fringe orders. The pattern used for phase extraction can be used for phase unwrapping directly. Fringes can be discerned even though the surface color or reflectivity varies with positions.

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This research purpose is by using two different photo-polymerization 3D print to produce microoptic devices. After comparing the effectiveness of the devices, photo-polymerization 3D print has better surface contour and resolution.
In this research, I use Arduino to detect the path of motor and control the laser output of optical pickup head. Making use of small focus and step width from optical pickup head and stepper motor, we can get a 3D stereolithography effect. I use Phrozen Sonic Mini 8K LCD printer to produce devices. Finally, compare the effects of the both.


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This study proposes DL-GSA, an optimized non-iterative algorithm that computes accurate holograms using an unsupervised learning convolutional neural network model. The DL-GSA is intended to improve the holographic display's computation speed and enable it to achieve real-time computation. According to the results, the average accuracy of the computer simulations generated using the DL-GSA is almost better than the Modified Gerchberg-Saxton algorithm (MGSA).

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A roll angle displacement measurement technique with high resolution for large range measurement is presented. The proposed technique is based on the birefringence effect and phase detection of polarization interferometry with a polarization camera, and the dual beam configuration can greatly eliminate the interference of pitch angular displacement to the roll angular displacement measurement system. The experimental results demonstrate that the resolution of the system can reach 0.038 arcsec with a 10° measurement range.

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We evaluate the performance of the mode recognition based on sparse coding for OAM beams affected by atmospheric turbulence in free-space optical communication. Since the sparse coding is a linear model machine learning process, the mode recognition results outperform the usual optics-based mode recognition using an inverse phase multiplication and a spatial filter.

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A probe laser light is integrated into a microscope so that the defocus of the microscope can be easily monitored from the movement of the light spot at the image plane. By this way, the sample can be located at the focus plane with error within ± 2μm.

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Optical phase reconstruction images generated by the homemade high-resolution wavefront sensor are carried out. The method of transverse differential interferometry is used to obtain the optical amplitude and phase information of microstructure, simultaneously. The wavefront sensor equipped with an optical microscope achieved the precise measurements of the phase-shift.

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This study focuses on an automatic detection system integration and application algorithm to detect defective ping-pong balls based on fringe projection profilometry (FPP). The experimental results show that the proposed system can perform fair detection rate and accuracy under suitable defective types and environment conditions.

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We developed a wafer warpage deformation controlling system consisting of a wafer cooling system, wafer surface profile, and temperature monitor system. Then, a correlation curve can be obtained between the wafer height change and the temperature change. Consequently, we could use this correlation curve to control the wafer surface height by adjusting the wafer surface temperature.

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Diffractive structured light is widely used in 3D sensing in which the projection images are usually performed using the diffractive optical elements (DOEs). The design of DOEs is based on Fraunhofer diffraction, however, the off-axis distortion and attenuation of light intensity occurs in the realized images. These problems lead to the decrease in the corner recognition accuracy and the recognition speed. In this paper, we proposed a modified method to solve the problems of distortion and light intensity attenuation. We thereby designed and produced the binary phase DOEs, and verified the diffraction patterns which are consistent with the original targets.

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A three-dimensional (3D) bright spot can be produced by specific scratches on a surface, which is called scratch stereogram. Here we calculated the position and direction of the scratches from a 3D model. The scratch stereogram is fast fabricated on a plate by CNC engraving.

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This paper presents a method to divide the fast Fourier transform (FFT) algorithm into two parts: the outer part is conducted by our codes and the inner part is conducted by MATLAB default functions. The outer part divides a very large array into small arrays and, in the inner part, the small arrays are conducted by MATLAB’s FFT in a temporal sequence. The small array returns to the outer part to complete the FFT that they are supposed to do. We applied this algorithm to the iterative Fourier transform algorithm and achieved the calculation of DOE with 4840×4840 pixels.

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With the advent of the global semiconductor 3-nm process era, the technology of non-contact measurement has become the core of current measurement development. In this study, an optical non-contact measurement system is developed for surface roughness measurement of wafers after wire-cutting. By introducing the relationship between surface roughness and the metrology of binary-image, producing the numerical analysis of regression curves, the surface roughness of the object to be measured can be quickly predicted.

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In order to improve the experimental accuracy, we redesigned the manual XY-axis platform of the microscope to motorized platform. And write a program to control the monochromator and the CCD scanning. Compared HSI with spectrometer to obtain the data of calibration.

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This research involved the classification algorithms and graphical user interface for hyperspectral images. The sharpness algorithm was added for image classification and the graphics processing unit (GPU) was adopted in spectral angle mapping (SAM) classification to compare the time consumption between central processing unit (CPU) and GPU. In this paper, we focused on the development of algorithms and the combination between algorithms and the GPU parallel computing. It is expected that the research can inspire innovation and achievability for pairing hyperspectral and machine learning.

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In this study, spectral analysis was performed on retinal images of hydroxychloroquine retinopathy and dementia; after analyzing the spectrum, we conducted deep learning for dementia, using a total of 3256 retinal images. Among them, according to Dementia, mild cognitive impairment (Mci) and Normal, the images are divided into training set and test set and then brought into four neural network models for training.

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In a depth scanning profilometer, the optical signals extracted from a short depth of filed are investigated. The local intensity modulation by projected fringe is analyzed and accumulated to rebuilt the surface profile of the inspected object.

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