Session Index

Single-shot phase imaging techniques based on parallel optical information processing are described. One is single-shot digital holography with Fresnel domain filtering using
phase modulation. Other is single-shot higher order transport of intensity phase imaging using
a computer generated hologram.

 

We proposed an imaging system with optical encryption. With the coded mask, the facial pattern wouldn’t reveal amid the whole process and thus keep the privacy. The intermediate images can be classified by VGG-11. Currently, with 170 training images, the system can fully recognize 43 testing images in 10 classes.

 

Based on the scheme of optical scanning holography, we applied a tera-hertz (THz) beam modulated by a diffuser to raster scan the object target. A complex intermediate pattern is synthesized using multiple raw patterns and then be demodulated by the pre-recorded system point spread function.

 

Compare to the Gaussian beam, the Airy beam provides larger FOV, higher axial resolution, and deeper penetration depth in a light-sheet microscope. Here, volume holographic grating (VHG) is fabricated for generating Airy light sheet. The present method may find important applications in designing compact illumination components for a light-sheet microscope.

 

This paper proposes and demonstrates the use of the edge-lit volume holographic optical element (EL-VHOE) as a reference waveguide to reduce the volume of a lensless digital holographic microscope. Additionally, a hybrid lensless Fourier transform digital holography is applied to make the EL-VHOE working as an objective turret.

 

We discuss the trade-off caused by the system parameters, and the performance degradation caused by the angular momentum of the rotational motor for shifting multiplexing. We also propose applying phase-integrated double-frequency grating shearing interferometer (PI-DFGSI) to makes the reading with moving disc being possible, and thus improves the system performance.

 

Radial and azimuthal polarization converters are capable to convert a light into radially and azimuthally polarized lights which have several applications. A new design of holographic converters is proposed and fabricated. This design has the advantages of high diffraction efficiency, suitable for low-cost mass production and has high application potential.

 

This paper proposes an innovative method for stereoscopic depth measurement by designing a computer generated hologram (CGH), which can diffract structured light patterns, and calculating the centroid distances of projected speckles on measured surface. The device was fabricated and system was performed to verify the feasibility of the method.

 

We present a study of theoretical finding of additional phase error of a volume
holographic storage disc during the reading process when the disc is rotated or displaced. It will
decrease the bit error rate of a phase-only signal. Then we propose a novel approach to solve
the problem.

 

A one-shot method to describe the profile of a rotating object is presented. A sinusoidal fringe pattern is illuminated on the rotating object. Fringes on the rotating object observed by the digital camera are blurred by the motion. The blurred fringes provide analyzable information to describe the surface profile.

 

This paper proposes a conceptual design for hybrid optical-electronic convolution neural network. The key design exploits the inherent advantage of 3D photonics architecture that provides inversion, multiplication, and summation of the images. This concept can be made possible by using today smart phones or tablets and high-definition liquid crystal displays.

 

Computation resources and machine learning have made a rapid progress in the last decade. Inspired by the computer science community focusing on data interpretation, computational optics took further step to investigate more possibility about the image formation. In this study, I will present some data-driven works including image denoising, phase retrieval and unconventional imaging system based on deep learning neural network.

 

A prism-hologram-prism sandwiched recording method is proposed for the fabrication of polarization-selective substrate-mode volume holograms with a large diffraction angle. The method belongs to a technique of longer-wavelength construction for shorterwavelength reconstruction and is much easier than that of traditional method which has high application potential in holographic photonics.

 

A novel deep learning model for particle detection and sorting in three-dimensions with digital holography was proposed and demonstrated. Deep learning models such as U-net and convolution neural network are implemented to predict and estimate the particle’s size and its orientations in lateral and axial directions.

 

In this study, the presented novel algorithm, based on the interferometry techniques, is used to rebuild the profile of the step height sample and the dirty position. By contrast, the phase unwrapping algorithm and the zero-order interference fringe fail to simultaneously rebuild the profile of sample and the dirty position.

 

This study presents the algorithm to distinguish the strong and signals, and the noise in the input of three images. All of the detected strong signal (or weak signal) can combine to the one stitching image. By contrast, the known Speeded Up Robust Features does not effectively distinguish these signals.

 

Recently there have been development in digital optics especially in laser beam machining, however designing miniaturized is still a challenge. We offer a solution by use of modified Gerchberg-Saxton algorithm to create computer generated holography that can focus a multi-focus spot light on four different focal planes.

 

The measurement introduces the maximum phase difference based on total-internal reflection, and the polarization interferometry with polarization camera. By finding the value of maximum phase difference and the relationship between maximum phase difference and refractive index, the refractive index can be obtained. The system’s resolution is 7 × 10-4 RIU.

 

This research uses the digital image relationship method to develop a large-area
non-contact residual stress measurement device. The digital image correlation method can
measure the residual stress in a two-dimensional plane. This research uses this technology to
measure the residual stress of the laminated test piece.

 

Holographic optical elements (HOEs) have been applied in augmented reality in many researches. In this study, polarization-dependent/independent HOEs as lens arrays were demonstrated which were fabricated in photo-curable monomer doped liquid crystal cells with holographic exposure processes. These HOEs were demonstrated their imaging capabilities in the integral imaging system.

 

In this work, we demonstrated a single pixel terahertz compressed sensing imaging system with mm-level resolution. During the experiment, terahertz beam is modulated by Bernoulli spatial light modulators. Reconstruction is then done through pseudo inverse algorithms. From the reconstructed images we showed that images are successfully reconstructed through Bernoulli masks.

 

In this paper, an optical 3D sensing technology was proposed. This technology manufacture a sensing device that can obtain shallow depth of field images and can perform certain accurately object depth sensing. This technology has the merits of a larger sensing range, lower manufacturing cost, and can be used outdoors.

 

This research involved the integration of spectral imaging camera and microscopy in conjunction with a white-light source to create a microscopic hyperspectral imaging system. This study focused on the development of hyperspectral imaging system with the aim of measuring chromatic aberration of the objective lenses.

 

This paper proposes an absolute optical rotary encoder (ORE) design with the optical resolution of 15 bits. It adopts a red laser as the light source cooperating with a Dammann grating and a high numerical aperture (NA) objective lens to generate multiple focusing spots on the encoded tracks.

 

We propose a digital holographic tomography developmental system with aberration wavefront compensation technique to measure the biological cell. The proposed prototype includes the hardware and measure processing. The preliminary experimental results show the three-dimensional refractive index tomographic imaging.

 

In this paper, we present a new approach to integrate digital holography and fringe analysis in three-dimensional (3D) composite surface measurement. Data analysis and image processing is performed for 3D image fusion to form a 3D composite surface profile.

 

Optical scanning holography (OSH) relies on the scanning by using an interference fringe and thus is sensitive to the environmental fluctuation. Here we demonstrated the common-path OSH to suppress the influence of environmental fluctuation and minimize the system form factor.

 

We proposed to generate multiple computer-generated binary holograms (CGBH) of the same scene by localized random down-sampling, adaptive sampling, and direct sign-thresholding. The holograms are displayed by intensity accumulation with a digital micro mirror device. With our optimized set of CGBHs, a high-quality reconstructed image without artifacts is obtainedㄡ

 

This study proposes an off-axis digital holographic microscopy (DHM) system for recording a digital hologram of living cells to obtain its cells features from the reconstructed phase. The cell features are further analyzed to identify the cell nature such as live or dead.

 

A volume holographic optical element is designed and fabricated using photopolymer (PQ-PMMA) for super Gaussian beam. A Lee hologram and Digital Micro Mirror Device (DMD) are used for this purpose. Super Gaussian beam generated by volume holographic grating with unique diffractive properties are advantageous for variety of practical applications.

 

3D information has become popular in recent years. In order to connect real world and virtual world, using RGB-D scanner is one of the methods. But it cannot work when encountering a plane, featureless, target plane. Our team proposed a feature coating technology to add feature and fix the problem.

 

A method of sending multichannel optical information through a multimode fiber (MMF) is presented by applying holographic Correlator method. Several optical characteristic has been discovered, and experiment results are presented and discussed.

 

n this paper, we present our investigations on capture the image of an object lying behind a thin turbid medium using in-line digital holographic technique. The results also show the feasibility of dynamical imaging through the thin turbid by in-line digital holography.

 

A holographic material using PMMA [poly(methyl methacrylate)] and EGPEA (ethylene glycol phenyl ether acrylate) incorporated with the photo-initiator Irgacure 784 is studied.

 

This paper presents the results of making diffractive optical elements (DOEs) to producing wide-angle diffraction patterns which can be used in structured light illumination for 3D scanning, including the preparation of target pattern, the design of binary-phase DOE, the manufacture of DOE wafers, and the evaluation of resultant DOEs.

 

We presented a method to achieving high-quality diffraction images of the diffractive optical elements (DOEs). The DOEs obtained using the proposed were far superior to those obtained using the iterative Fourier transform algorithm in terms of PSNR (1301.2%) and uniformity (96.1%).

 

Metasurfaces are planar devices containing nanoantennas or resonator arrays that allow for beam shaping, super resolution imaging, and holography. Metasurface holography technology combines a computer-generated hologram with a nanoscale device. Hybrid metasurfaces with tunable phase change materials provide a platform for active modulation of wavefronts. and opportunities for switchable functionalities.

 

Fringe projection profilometry is a powerful and useful tool in three-dimensional measurements for many applications. We present a scanning approach using fringe projection in different shallow depth of fields along z-axis to retrieve and rebuild the surface of a small inspected object. The designed fringe pattern is projected on the inspected object with a shallow depth of field. Then, a CCD is used to capture the image of the inspected object with projected fringe in a narrow depth of field. A 2D contour of the inspected surface addressed by the in-focused fringes is obtained in one scanning process. The retrieved images from the scanning process are assembled to build the 3D surface of the inspected object. Based on the limited depth-of-field of the pattern projection system and the limited depth-of-focus of the image acquisition system, the precision of the profilometry system is improved.

 

In this study, we proposed optical configurations to fabricate radial grating and use fabricated grating to measure a rotation angle of a rotational stage. The grating period of radial grating gradually changes with the radius, so it has the advantage of multiple angular resolutions.

 

Different from other simulations, we developed a matrix-based simulation model for the optical force on the arbitrary sample under an arbitrary light field. To testify the accuracy of this model, this paper shows the simulation and experimental result for the uniform spherical sample under the Gaussian beam.

 

The purpose of this paper is to improve the non-uniform illuminated region by using exponential correction method. The experimental results show that non-uniform illumination often results in undesirable depth map. First we pre-process the image with exponential correction, then the depth map can be recovered by shape from focus (SFF).

 

A 3D lens structure can be prepared by stereolithography set-up which including a high resolution phase-only LCoS, z-axis direction translation stage. Using 1 mm radius of curvature as target, resulting 0.91 mm height 2.03 mm of base diameter printed objects were achieved. The error is estimated at 2.7%

 

This study provided a novel H2O2 sensor which integrated an enzymatic sensing film on the backside of a holographic plate. Results showed the proposed method provided high stability and resolution within the measurement range of 1 ppm to 10 ppm.

 

We use low-cost aspheric lenses, Raspberry Pi CMOS modules and white LED lights to build an optical system with a neural network YOLO algorithm to automatically calculate whether the number of red blood cells in the blood is normal.

 

Through the projection light image analysis method, the light intensity distribution of a free form surfaced LED can be accomplished much faster than other approaches. Comparing the optical experimental results of the LED lamps by Gonio-photometer and the proposed projected light image analysis method,

 

Abstract: Combines hyperspectral imaging and deep learning to propose air pollution detection method.Use the visible light hyperspectral imaging technology is given Hyperspectral information.Through the classification algorithm,3D-CAE and PCA are respectively proposed and combined with VGG-16 to discuss the optical haracteristics of air pollution and the accuracy of model recognition.

 

This study presents a particle detection method by using novel phase encoded method in common-path DHM. The particles at different slice of the sample can be measured by using virtual spatial filter recording technique which can avoid the diffraction information from the other slice of the sample.

 

PQ:PMMA can be dissolved in oxolane solvent and dispersed on glass substrate to form a film. Applying doctor-blade method with thickened solution, a rather uniform PQ:PMMA film can be formed. Series test on recording hologram grating on such film were performed and a corresponding model is established.

 

The simplified equations of astigmatism and anamorphic for waveguide combiners were proposed in this paper. The results of the equations matched to the simulation of the commercial ray-tracing software Zemax. It will make the designing process become simpler and faster.

 

An error-controlled method using pulsed-encoded patterns to identify fringe orders for phase-shifting projected fringe profilometry is presented. Phase-extraction and unwrapping can be performed directly by the pulsed-encoded patterns. There is no need to take additional projections for phase unwrapping.

 

A one-shot method using the two-dimensional fringe-encoded pattern for Fourier transform profilometry is presented. The 2D fringe-encoded pattern provides additional information to identify the fringe order. Even though the surface color or reflectivity varies with positions, fringe orders can be identified precisely.

 

We present a method for phase quantization of diffractive optical element (DOE) which combines the iterative Fourier transform algorithm, a backward quantization method, and the large-error reduction algorithm. The method has been effectively and in high efficiency applied to binary-phase DOEs.

 

The work is devoted to development of a new method for rapid estimation of the concentration of optical defects in the form of nonlinear refractive index inhomogeneities. The proposed method is based on analysis of the angular spectrum of diffraction patterns obtained using previously demonstrated TRIDH method.