Session Index

Label-free quantitative 3D phase imaging techniques are becoming increasingly important and popular in biological and medical applications for measurements and monitoring of cells, cell cultures and tissues. In particular, the possibility of the quantitative three-dimensional (3D) representation of living samples holds tremendous potential for advancing the field as it would provide unprecedented ease of insight into subtle intracellular mechanisms.

In this talk I will discuss the recent progress and trends in development and applications of 3D QPI systems based on optical diffraction tomography (ODT) with holographic projections. The presentation will focus on algorithms and systems which allow to overcome the most important issues such as: (i) lack of isotropic and sufficiently high spatial resolution essp. in the case of limited angle optical diffraction tomography(ODT), (ii) lack of the chemical specificity (general feature of QPI methods), (iii) multiple scattering which limits the size (thickness) of investigated samples (tissues, small scale objects) and (iv) lack of efficient solutions for in-vivo tissue investigations (such as in the case of optical coherence tomography (OCT)). The discussed solutions will include utilization of unified k-space theory of OCT which allows to provide an efficient use of combined OCT and ODT approaches, development of multimodal systems combining ODT with fluorescence microscopy and ODT with Raman spectroscopy, as well as applying AI solutions to support better reconstruction of biophysical parameters of cells and tissues.

However 3D QPI systems to be fully quantitative require proper metrological approach to assess the accuracy and precision of measurement. This problem is most often overlooked in both research and commercial QPI systems and there are no standardized methods for testing and reporting their metrological performance. Therefore I will also present the methodology for metrological evaluation of 3D QPI instruments for biomedical applications. The methodology entails suitable phantoms, quality assessment metric and easily reproducible protocol that is attainable for both numerical and experimental analysis. We demonstrate its applicability by comparing simulated and physical reconstructions obtained from 3 holographic tomography systems. The results will serve as a reference point for past and future research, encourage to benchmark new systems in a similar manner and further the efforts towards the standardization in 3D QPI metrology.

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Here, we propose a snapshot hyperspectral imaging system incorporated with the meta-optics concept and a small-data convex/deep (CODE) learning theory. Our hyperspectral imager contains only one single multi-wavelength metasurface chip, greatly reducing the physical size of device. To demonstrate the high performance of imaging system, a single-shot 4-band multispectral image is taken as the input. Consequently, a high-fidelity 18-band hyperspectral data cube is generated using the CODE-driven imaging system. We surmise that the metasurface-driven hyperspectral imaging combined with CODE small-data learning theory can pave a new way toward fundamental science studies and real-world applications with low-profile advanced instruments.

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Digital holographic microscopy (DHM) is a useful quantitative phase imaging
technique for observing transparent samples. In DHM, the diffraction grating is a widely used
component to implement the common-path configuration which helps stabilize the system and
reduce environmental fluctuations. However, the multiple unwanted higher-order diffraction
beams of grating lead to the system power loss. Here, we proposed using the volume
hologram (VH) to satisfy the common-path DHM configuration. By utilizing the single
diffraction order characteristics of the volume hologram, our proposed setup enhances system
stability while maintaining system power usage.

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We have developed a machine vision-based Automated Optical Inspection (AOI) system capable of automatically detecting defects in small electronic connectors and marking them for subsequent processing. This advancement serves to enhance the objectivity and accuracy of the inspection process.

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In this paper, we demonstrate the fabrication of the Geometric Phase (GP) optical device in an nematic liquid crystal cell (NLC cell) by using photo-alignment technique with poly[1- [4-(3-carboxy-4-hydroxyphenylazo)benzenesulfonamido]-1,2-ethanediyl, sodium salt] azo-polymer (PAZO) as alignment layer. In experiments, GP grating optical element is fabricated and tested. The design principle, fabrication and characterization of GP devices are presented and discussed.

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For a periodic 64-channel optical phased array (OPA), we propose a novel approach combining the grouped phase error correction and beam steering with (n-1) stages and using 1D search algorithm with fixed and iterative weights. We leverage the power of parallel processing to reduce computation time significantly. The proposed method is 8-10 times faster while achieving results of 12.9-dB PSLL, 75% peak intensity with fixed weight, and 66% peak intensity, 15.68-dB PSLL for iterative weights.

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The efficacy and safety of traditional Chinese medicines highly depend on the quality of raw materials and process of preparation. Researchers have drawn attention to terahertz spectroscopy, using non-destructive method to conduct compositional analysis of Chinese medicines through their fingerprint spectra. Due to varied experimental conditions and data processing models adopted by different labs, integrated THz spectral database have yet to be available, nor does the standard operational procedure. Herein, we focus on the establishment of a systematized procedure for THz-based material analysis, such technique can provide powerful and time-effective quality monitoring of various Chinese herbs and medicines.

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In this study, we propose a deep learning-based three-dimensional (3D) surface imaging method for specular and diffuse reflection composite surfaces. The proposed system combines artificial intelligence for 3D optical measurement integrated with digital holography and fringe projection technologies. 3D fusion by 3D segmentation and alignment for composite surfaces are driven by artificial intelligence processes. The experimental results show that the proposed method can achieve competitive performance on 3D surface imaging using the deep learning-based integrated coherent system.

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We proposed a lensless encryption face recognition system based on deep learning. An amplitude-modulated mask is applied as an element for optical encryption. Then, a ResNet-50 architecture was trained to learn a well-structured representation space for the visual recognition task. This concept was validated by 10-class dataset with 90% sensitivity and 98% specificity, respectively. Such unconventional optic offers a variety of different possible setups.

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In this study, we propose a deep learning-based three-dimensional (3D) surface imaging method for specular and diffuse reflection composite surfaces. The proposed system combines artificial intelligence for 3D optical measurement integrated with digital holography and fringe projection technologies. 3D fusion by 3D segmentation and alignment for composite surfaces are driven by artificial intelligence processes. The experimental results show that the proposed method can achieve competitive performance on 3D surface imaging using the deep learning-based integrated coherent system.

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In this paper, we present a theoretical model for color breaking in a holographic-optical-element-based augmented reality (AR) display. The discussions about the design parameters of holographic optical elements (HOEs) for AR glasses, focusing on color uniformity as a function of the waveguide thickness, are conducted. This model can be used to evaluate the color breaking of a displayed white image from the user’s point of view. The simulation results show that color breaking occurs due to the limitations of pupil size and image shifting caused by the extended eye-box. Moreover, the thickness of the waveguide also causes uneven color distribution.

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This research introduces a light-derive phase modulator based on dye-doped liquid-crystal (DDLC) films with a single-side rubbed cell. By using different polarized beams to stimulate azo dye, the alignment of the liquid-crystal demonstrates a change. The characteristic is harnessed for recording and erasing information. This optical element can be likened to a reusable computer-generated hologram (CGH).

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The purpose of this study is to explore the integration of 3D printing of photo-polymerization with the polymer-dispersed liquid crystal (PDLC) technique to create 4D printing optical devices. The printed 3D elements, including Fresnel lenses and gratings, are combined with polymer-dispersed liquid crystals, which enable the printed 3D elements to possess the ability of varying light intensity and therefore exhibit the characteristics of 4D printing. This study demonstrates the possibility of simplifying the fabrication processes of
switchable optical devices, improving limitations of 3D printing, reducing production cost, enhancing manufacturing efficiency, and offering the potential of a new configuration of 4D printing.

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This research is devoted to developing a portable and user-friendly 3D coordinates point cloud acquisition system that is cost-effective and resistant to external light interference. Unlike conventional techniques, this system is integrated with a single inertial measurement unit (IMU) and a planar optical displacement sensor for the 3D scanning. By measuring variations in tilt angles and displacement distances of the object, we can derive a rotation matrix that enables the conversion of a 2D displacement vector into a representation in 3D space. Finally, through the integration of minute coordinate variations for each dataset, the point cloud acquisition could be completed.

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This study presents a method to improve the exposure uniformity of a hologram printer by using localized adapt modulation. By measuring the actual illumination of the projected light pattern, an adapt mask function, which can compensate the nonuniformity, is produced and incorporated into patterns to be displayed on the DMD. The results indicate that the uniformity of the projected light patterns is significantly improved.

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This paper combines Otsu's binarization and accumulated intensity values to detect the installation arrangement of aluminum plates. The installation arrangement was the one of the 2023 intelligent robot competition topic presented by CHENBRO CO. and SYNTEC TECHNOLOGY CO (real industry requirement). Otsu's binarization can reduce the brightness influence in the environment. The accumulated intensity values are designed for the installation arrangement. In the experiments re-build by our laboratory (avoid the problem of product confidentiality), compared to YOLOv8 with the 80 images and running time 3 hours, the proposed algorithm effectively uses one image and running time 5 minutes.

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This research focuses on spectral analysis and deep learning of air pollution images for PM2.5 and water quality images for BOD (Biochemical Oxygen Demand). A total of 150 air pollution images and 90 water pollution images were used for this study. These images were divided into training and testing datasets, and then fed into two neural network models for training. Finally, the accuracy of the model predictions was evaluated.

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In this paper, a method for reconstructing the surface color of an object was proposed. It is based on the R, G, and B projected technology, and color theory regulated by the CIE color system, so it has the merits of simple optical structure and convenient operation, and quick analysis. In the experiment, a coin was used to verify the feasibility of the method, and the surface color has a good effect of restoring.

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A 2D fringe pattern is designed and employed to perform 3D profile measurements by means of coaxial fringe projections and image acquisitions in short depth of field. To enhance the reliability and systematic accuracy, a signal processing algorithm is proposed as well. Accuracy of the retrieved 3D profile can be achieved in the order of sub-millimeters.

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TBA

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In this work, we propose an algorithm for simultaneous determination of optical constant and sample thickness in transmissive time-resolved terahertz spectroscopic measurements. Based on Fresnel equation and Fabry-Perot effect, we construct the transfer function of the unknown sample in terms of sample thickness and its optical constant. Through an iterative fitting procedure, one can come to the optimal results. Our results show that under certain reasonable restrictions, the derived outcomes are in good agreements with published results. Such formulation can be further expanded to multilayer structure, which may contribute to non-destructive characterization of functional devices and packaged ICs.

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The recent surge in multimedia users and internet traffic has strained low data rate Radio Frequency (RF) systems. To meet the growing need for higher data rates, the transition from RF to optical domains is accelerating. Free Space Optical (FSO) communication stands out as a solution, offering robust bandwidth for wireless connectivity between remote locations. However, FSO systems face atmospheric challenges, which Adaptive Optics combats by real-time correction of turbulence-induced distortions. Signal interference is also addressed through Sparse Coding, reducing the number of patterns. Our team developed a coding method to ensure both signal quality and efficient information transmission.

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Light-emitting diodes (LEDs) are the lighting elements on computer, cell phone, and television screens. Understanding LED irradiation effects on the human eye is crucial to vision care. This study investigated the effect of LED (violet, blue and red) irradiation on human retinal pigment epithelial (RPE) cell line ARPE-19, which can be observed through digital holographic microscopy (DHM) to assess cell morphology. The experimental results on cell morphology and viability indicate that ARPE-19 cells were more harmful under exposure to violet and blue light, but not significantly changed with red light irradiation.

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A volume holographic material based on the ethylene glycol phenyl ethyl arylate (EGPEA) monomers with various initiator concentrations in the host matrix PMMA is synthesized. The advantages of lowering the initiator concentration, including a rather short initiation time within few seconds and a sharp rising optical response, are demonstrated. For a polymer with a thickness of 190m and an illuminating power density of 2mW/cm2, a Bragg grating with the diffraction efficiency of 95% can be formed in 80 seconds.

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This study proposed a scanning computer-generated hologram (CGH) display system to increase the field of view (FOV). A holographic screen is utilized to achieve the see-through function. A scanning mirror is utilized to enlarge the FOV. The aberration caused by the holographic combiner is analyzed and corrected. In our case, we achieve 21 degrees horizontal FOV with 6.4 μm pixel size SLM. The eyebox is 5.8mm (horizontal) by 4.6mm (vertical) while the resolution of SLM is 1920 (horizontal) by 1080 (vertical).

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This paper is developed, simplified, and optimized from [1] in order to distinguish the proposed focal curves of the blemish from the curves of the smooth-surface sample. In this paper, the novel idea presents calculating the number of slope variations in the image mask. By contrast, the traditional auto-focusing algorithms (such as Square gradient) are based on calculating the intensity gray-values in the image mask. These traditional algorithms are not suitable in the fringe cases of the smooth-surface sample containing the blemish. In the following experimental results, the proposed algorithm presented the high-effective results.

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Model predictive control (MPC) predicts future events using current measurements and adjusts control processes accordingly. In our adaptive optics system (AOS), we integrate U-Net with Shack-Hartmann wavefront sensor (SHWS) propose a deep learning (DL) method to reconstruct the wavefront. This DL-SHWS is integrated into the MPC controller, effectively correcting wavefront aberrations in simulations and enhancing both speed and accuracy. The future goal is to realize real-time control through robot operating system implementation for the MPC-based AOS.


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Two-dimensional (2D) layered materials demonstrate extremely high optical anisotropy that gains an enormous interest for integration in polarization nanodevice applications. Here, we present variety of synthesized 2D nanolayers/ flakes with their atomically thin structures confirmed by Raman, AFM and TEM analysis. Furthermore, high birefringence has been measured. We also demonstrate a polarization-plane rotation when linearly polarized light propagates through 2D nanoflakes that open a new road to integrate into atomically thin optical elements.


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Here, we demonstrate the feasibility of transparent and conductive Aluminum-doped Zinc Oxide (AZO) thin films to operate simultaneously as electrode and alignment layer in Liquid Crystal (LC) device assembly. Controlling deposition process AZO layers with very high transparency and excellent conductivity were obtained. The exceptionally low surface free energy of (100) oriented AZO, along with the topological modification following mechanical rubbing treatment were used to elucidate the ordering mechanism of LC molecules on the surface of AZO film. The quality of the alignment and competitive electro-optical performance of the assembled LC device reveals the great potential of AZO thin films.

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In this study, unknown grating period measurement of a reflection type grating can be determined by a heterodyne grating interferometer. The experiment results showed that the difference between proposed method and commercial product specification can be better than 10 nm.

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This research is based on Fizeau-type polarization interferometry and employs a polarization camera, which enables full-field measurement of the wafer surface topography. Polarization interference patterns are acquired from a Fizeau interferometer using the camera, which outputs four phase-quadrature interference patterns. The surface topography of the wafer can be determined by applying a phase-shifting algorithm to the four phase-quadrature interference patterns. The method only requires the acquisition of a single interference image to calculate the surface topography of the test object, making it suitable for measuring the surface topography of continuously curved surfaces and polished materials with various reflective properties.

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Developing a three-dimensional shape measurement system based on shape-from-focus for measuring micron-scale processing holes in transparent materials. The system achieves a horizontal resolution of approximately 1.16 μm and a depth resolution of around 2 μm.

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We introduce ultrafast motion pictures of light propagation obtained by light-in-flight recording by holography (LIF holography). LIF holography has the following advantageous features: (1) recordability of spatiotemporally continuous motion pictures of light propagation, (2) recordability of three-dimensional images of propagating light, and (3) ultrahigh temporal resolution. We also review recent advances in LIF holography.

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In this study, novel heterodyne light source was constructed by spatial light modulator (SLM), in which the time-varying phase distributed pattern generated by the iterative Fourier transform technology to simulated a moving grating structure in SLM.

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A sinusoidal intensity modulated light source as a test signal and incident to a spectrometer. In order to separate the tested spectrum from a stray light mixed spectrum, the three-parameter sine fitting algorithm was used to calculate the amplitude intensity corresponding to the specified modulation frequency. The extracted test spectral signal was not affected by stray light. And it is developed on the mobile phone, and the separation spectrum can be obtained by using the mobile phone program.

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In this paper, we show the calculation for volume holography optical element (VHOE) by VOHIL model. The phase maps visualize the phase consistency and the diffraction as well in various conditions. The model shows the accuracy of the diffraction from a volume hologram. Using VOHIL model, we visualize the diffraction property in reflection-type VHOE and make sure the limitation when designing a VHOE.

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This study accomplishes the auto-labeling of microscopic hyperspectral images, alleviating human involvement in labor-intensive tasks and subjective assessments. This paper outlines the methods employed for auto-labeling, encompassing noise removal through the median filter, feature extraction via the N-finder algorithm, and labeling facilitated by the spectral angle mapper algorithm. Additionally, we introduce a fully-connected neural network model for cellular classification and present preliminary findings.

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In the research, the hyperspectral imaging technology (HSI) was used to analyze the small tomato, and the spectral information obtained by the image through this technology was used for the analysis and prediction of the Brix of the small tomato, hoping to improve the existing sugar detection method.

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This study is to simulate the effective power change when wearing high-curvature single tilted prescription lenses at different single tilt angles. The results show that the more the tilted angle, the less effective power change occurring at peripheral area of the high-curvature lens, but not for the low-curvature lens. Moreover, the power change profiles are different between high-curvature and low-curvature lenses, which verifies the importance of the lens design. It is suggested that an optical system combining a spectacle lens with a model eye is more suitable for the realistic simulation of power change of tilted prescription lenses.

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Optical filters have many important scientific applications. In this study, a recording method for narrowband volume holographic filters is proposed based on the K-vector geometry of coupled-wave theory. A special recording setup is employed with a right-angle prism to guide reference and object beams. Photopolymer holographic recording material is used with a 532nm laser to record a narrowband volume holographic filter with a central wavelength of 712nm and a full width-half maximum of 18nm. This method should offer advantages such as a simple and fast setup and flexible design parameters, providing a manufacturing solution with potential applications for narrowband filters.

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Scanning holography scans the object by a structured light and detects the scattered light as the holographic information. By applying a computational method, the three-dimensional image of the object can be reconstructed. Here, we propose a new technique scanning holography in which interference is avoided and thus the scanning speed can be faster.

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The study describes a spectral reconstruction approach using RGB image and spectral data to identify the relation between the colorimetry and the wavelength of commercial display devices for human visual needs. The experimental results confirmed the successful reconstruction of hyperspectral images from a single RGB image and reveal possible harmful spectral distributions which might be avoided in display devices design.

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Fringe projection techniques based on phase-shifting algorithms to retrieve the 3D surface profile always take three or more measurements. In this paper, a one-shot method using the phase-shifting technique to describe the profile of inspected objects is presented. Accuracy of the presented method could be as high as those measured by a typical phase-shifting technique.

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Array output cylindrical vector beam converters are devices that can transform linearly polarized incident beams into multiple radial or azimuthal polarizations with arrayed outputs. The generated radial or azimuthal polarization offers numerous advantages and finds significant applications in various fields. However, currently available converters mostly allow the output of only one radial or azimuthal polarized beam. In this study, we propose a polarization converter based on a Mach-Zehnder-like interferometric structure, capable of simultaneously outputting four radially or azimuthally polarized beams. This device could enhance the application potential and efficiency in laser processing or detection.

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In this study, we use a simple method for multi-wavelength measurement. Add different sine wave modulation frequencies to two different wavelengths in the color mixing light source. The three-parameter sine wave fitting method was used to separate two waves of different wavelengths. Applying this method to the overlay measurement in the semiconductor manufacturing process. The waveform data of the two signals can be obtained with only one acquisition, to improve the problem of consuming a large amount of measurement time.


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This paper proposes an optical system for measuring the retardation of a wave plate using polarized vortex light interferometry. In the proposed system, the retardation of a wave plate can be estimated through measuring the inclination of the dark fringe generated by interference between two orthogonally polarized vortex light beams. The measurement accuracy of the phase retardation of the wave plates were estimated to be nearly 0.14 deg.

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Currently structured light is one of the frequently-used techniques for 3D sensing. When designing structured light on a large scale, problems such as distortion and light intensity attenuation must be solved, which result into the farther away from the center and the lower the recognition speed and accuracy. This paper proposes a correction method for image distortion and design of images with high resolutions such as 4840×4840 pixels. After processing with various algorithms on diffractive optical elements (DOEs), we effectively increased the quality of the designed image. The DOEs were verified in numerical simulations and experimental physical samples.

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This research proposes a novel AR-HUD system that uses an optimized DL-GSA algorithm for generating holograms. The algorithm employs an unsupervised learning convolutional neural network model to accurately generate holograms with different depths, enabling real-time calculations and dynamic AR-HUD images for enhanced driving safety and convenience.

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We proposed and demonstrated a low-coherence digital holographic microscope which combination with a phase contrast architecture. The phase information can thus be obtained from different layers of the transparent sample.

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In response to the growing demands for safeguarding confidential information and
protecting individual privacy, this research introduces a novel approach to digital holographic
encryption using Convolutional Neural Networks (CNNs). The study employs a phaseencoded digital holographic encryption system to secure object images, such as fingerprints.
The primary focus is on leveraging the U-Net architecture to construct an effective CNN
network for decryption. Experimental results demonstrate the CNN network's efficacy in
decrypting information and restoring digital holograms, with potential applications in digital
holography and cryptography, including message recovery.

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A roll and pitch angular displacement measurement technique is presented, which is based on the birefringence effect and phase detection of polarization interferometry with a polarization camera. The experimental results demonstrate that the maximum error is 0.041° for roll and 0.18° for pitch, and the system measurement range of 3° for both roll and pitch angles.

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In this work, we used a commercial terahertz spectral meter and digital micromirror device (DMD) to establish a compressed sensing system. The imaging system is driven by an asynchronous optical sampling system (ASOPS). Different objects are successfully measured and reconstructed under different frequencies. The experiment result can be justified with the ground truth.

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Traditional optical imaging directly records the refracted signal through a lens system. However, the image resolution is constrained by various physical limitations. Modern efforts focus on overcoming these restrictions to enhance resolution. This article will provide several methods for improving image resolution, including the implementation of post- processing techniques such as resampling and deep learning methods. A comparative analysis will reveal the most suitable method for enhancing image quality in different scenarios.


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Holographic technology has attracted a great deal of interest in the fields of optics over the world owing to its potential use in future optical applications such as holographic imaging and optical data storage. In this study, we would like to achieve the full 2 phase distributions by using a metasurface with liquid crystal module under different polarization. In this method, hologram can be selected by changing the incident polarizations. Finally, we obtained the phase shifts with 4 level modulation by simulation.

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The molecular orientation of liquid crystals can be tuned by electric field resulting corresponded optical effects. In particular, liquid crystal on Silicon(LCOS) with small pixel array is a good candidate for dynamic spatial light modulators (SLMs). Dynamic phase modulation in the visible and near-IR region of LCOS has its advantage besides the intensity modulation applications.
In this talk, we will discuss how to achieve the high performance phase modulator in terms of phase precision and phase accuracy. In addition, the cause of pixel-level crosstalk effects and its suppressing solution will be discussed. Finally, the latest and future developments of LCOS.



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This study explores the use of autoencoder-based image processing to enhance GaN-based metalens images, addressing blurriness and color cast issues. The autoencoder model transforms blur images into low-dimensional vector, enabling the reconstruction of clear output images. Its effectiveness in handling severe color cast and demonstrates its potential in improving image quality, making it a promising solution for compact cameras with metalens technology.

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This study combined structured illumination technique, capturing images by changing azimuth and phase of structured light patterns, with our developed Mueller matrix imaging system to obtain resolution enhanced images which reveal more detailed polarization features of the sample. The wild-field and resolution enhanced images were demonstrated to prove the enhancement effect of this approach.

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In the paper, the information of the holographic storage system is multiplexed and recorded in the same area. By shifting the holographic plate, the readout position corresponds to a change in the wavefront of the reading beam, resulting in a phase change in the recorded information. Therefore, we design the phase of the superimposed signals to produce interference during the shift readout process, allowing for variations in signal intensity corresponding to different shift distances. Additionally, utilizing the information in reciprocal space enables higher uniformity in the readout information.

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HoloLens, nearing true mixed reality, employs tiny displays to project virtual images. Using Volume Holographic Optical Elements (VHOEs) as waveguides, it addresses the size-weight challenge faced by Head-Mount Displays (HMDs). However, VHOEs also counter diffraction and color issues. Leveraging VHOEs' Bragg selectivity, transparency reaches almost 90%, surpassing peers. Thus, we use this in our main focus: embedding lens systems in VHOEs, examining clarity. This aids future research on enhancing image quality.

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An azobenzene holographic material based on the {[4-(dimethylamino) phenyl] diazenyl} benzoic acid (Methyl red) for dynamic holographic recording is synthesized. The change in refractive index is induced by 532 nm DPSS laser with a total power intensity of 200mW/cm2. The first order diffraction can be detected in 0.3 seconds. Without holographic recording, the grating disappeared in 0.5 seconds. The rapid response in holographic recording /erasing makes it possible in dynamic applications.

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Scratches at specific locations on a smooth surface can produce three-dimensional bright spots, which is called scratch stereograms. Here, we took points from the input 3D model and calculated the location and orientation of the scratches. The scratch stereogram is fast fabricated on a plate by CNC engraving.

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This paper presents a prototype of near-eye display device, containing a fiber source, a liquid-crystal-on-silicon spatial light modulator (LCoS-SLM), and a holographic optical lens (HOL). The total length of the presented apparatus from a fiber source to the LCoS-SLM is about 12 cm and the projected image was observed 25 cm behind the LCoS-SLM. The image is created from a diffractive optical element (DOE) displayed on the LCoS-SLM. The DOE is calculated by iterative Fourier transform algorithm (IFTA) followed by multiplied with a quadratic phase term to mimic a convergent lens.

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This study provides a method for tracking features on cardiac surface vessels for determining the heart rate by applying convolutional neural networks (CNN). We designed a complete procedure to accomplish this task, which includes image preprocessing, CNN model training, and sliding windows algorithm for feature finding. We tracked two features accurately and estimated the heart rate by analyzing the distance between them. This research explores the implementation of deep learning for extracting heart behaviors from a series of recorded medical images and the potential advancements in cardiac dynamic analysis and surgery monitoring.

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In this work, we perform a systematic study of different deconvolution techniques, namely Wiener, Richardson-Lucy (RL), and the innovative Richardson-Lucy with total variation (RLTV), and compare their performance. Our results indicate that RL deconvolution outperforms Wiener regarding contrast enhancement and drastically improves image quality. RLTV is effective, efficient, and accurate, which may find important applications in high-resolution imaging.

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The Moiré effect is a frequently employed image processing technique in optical measurements. In this paper, we employ MATLAB programming to numerically simulate and analyze the interference patterns of Moiré fringes based on the relative rotational angles and relative period ratios. Gaining insight into these Moiré pattern characteristics will aid in the application and development of digital Moiré effect measurement technologies.

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In this study, a 532nm green laser projects diffractive optical elements (DOE) in a spatial light modulator (SLM) to produce multiple 2D images separated in different spatial layers. Each layer's DOE was created using the iterative angular spectrum algorithm (IASA) for imaging in optical near field. Several techniques were employed to improve the image quality: Image shifting separates target shapes from SLM's reflection, temporal superposition reduces the speckle noise, and grayscale integration improves object continuity. The process shapes target objects using high-transparency resin, offering benefits of internal visualization, vertical continuity, and efficiency despite limited vertical variation and operational experience requirements.

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Defects in compound semiconductor wafers may affect the lifetime as well as decrease the performance of the power devices. Therefore, in this study, we demonstrated a computational refocusing algorithm in combination with a high-resolution swept-source optical coherence tomography (SS-OCT) system setup to enhance the contrast of the defect images in silicon carbide (SiC) wafer. The location, distribution, and size of defects, including macro pits, stacking faults, micropipes, and particle inclusions, were analyzed quantitatively.

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This work focuses on using deep neural networks for reconstructing structural parameters from spectral information. RCWA MATLAB code is used to simulate spectral signals (Psi and Delta) for different FinFET-Fin parameters. Simulated ellipsometric scatterometer data is utilized to train the inverse neural network (INN) by using PyTorch. The INN extracts critical features through convolution, aiming to predict accurate structural parameters by comparing outputs with actual values. On the other hand, contrary to INN, the forward neural network (FNN) predicts spectra based on structural parameters through transposed convolutions.

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The edge contrast enhancement can be explained using Hilbert and fractional Hilbert transforms. Implementation of spiral phase filtering can be performed experimentally or by image post-processing. Here, we performed a systematic study to demonstrate the effect of the order of phase singularity of the spiral phase mask on edge contrast enhancement. The effect is demonstrated using the simulation. It is observed that by continuously varying the order of phase singularity, the edge enhancement can be altered in a systematic manner. A continuous change of enhancement can be achieved from an anisotropic left to perfectly isotropic to an anisotropic right edge.

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Using a 532nm green light laser as the recording light for intermittent exposure of the PQ/PMMA material through the two-beam interference method. This process can create periodic refractive index change structures in PQ/PMMA. Subsequently, detecting the diffraction efficiency by changing the light intensity, exposure time, and diffusion time, while also determining how they affect the diffraction efficiency. Finally, with the above experiment, the diffusion coefficient of PQ molecules will be found.

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In this work, we demonstrate a technique to detect the positions of vortices using a digital micromirror device as a scanning triangular aperture and by measuring the intensity at the center of a pattern using a digital pinhole.

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