Session Index

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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