Session Index

We propose a beam scanning with aberration compensation using phase-only spatial light modulator to avoid the vibration and reduce the aberration from the optical element in each scanning angle. The experiment results show we can achieve high resolution and high quality of the sample in the optical system.

 

We demonstrate the generation of abrupt autofocusing beam through volume holographic gratings and studied their transverse acceleration, nondiffraction, and self-healing properties. Utilizing the unique diffraction properties of volume holograms, polychromatic abrupt autofocusing phenomena can be observed. Present results may find important applications in field of laser-material interaction at micro levels.

 

We presented a novel mechanism for generating high-quality diffractive images in the variable image error reduction algorithm (VIERA) of optimizing the diffractive optical elements (DOEs). The DOEs obtained using VIERA were far superior to those obtained using iterative Fourier transform algorithm (IFTA) in terms of PSNR (1301.2%) and uniformity (96.1%).

 

We present a reconstruction method based on deep learning for particle detection using off-axis digital hologram for the detection of the lateral and axial positions, and the size of the three dimensional particle. The proposed detection performed on convolutional neural network can achieve high accuracy of position on three-dimensional space.

 

Wide-angle patterns generated by diffractive optical elements (DOEs) have been applied to structured light 3D profiling. We present a method to designing the DOEs to generate random-spot patterns which corrected the distortion and intensity attenuation. The DOEs were design using the iterative Fourier transform algorithm and the direct search algorithm.

 

We present an investigation on the preparation and characterization of thick photopolymers for holograms recording at 532 nm. Based on our previous results, we develop a thick Irgacure 784 doped PMMA photopolymer for reflection-type holographic recording with enhanced sensitivity at 532 nm.

 

The developed system introduces different phase shifts based on the reflected light of the vertical and horizontal polarization states when total reflection occurs. By calculating the maximum value of the phase difference between vertical and horizontal shifted phases, finding the relationship between the refractive indices, the refractive index is derived.

 

The reconstructed image of a single binary hologram generated by down-sampling always contains artifacts due to down-sampling lattice. To suppress the artifacts, three different sampling strategies and time-multiplexing are proposed. The quality of the generated binary hologram can be significantly improved while the computing cost is low.

 

In this report we present numerical algorithms for simulation of femtosecond laser pulses interaction in nonlinear optical media. Due to high intensity of pump laser pulse, generation of phase shift gradient is observed. This results in diffraction of probe wave featuring structural inhomogeneities of nonlinear refractive index in investigated object.

 

A Computer-Generated Hologram(CGH) based on Fresnel diffraction formula was implemented in a high resolution phase-only liquid crystal on silicon (LCoS) for 3D printing. A three-dimensional object with a height of 1.53 mm and a width of 6.32 mm without a translation stage can be fabricated

 

We demonstrate the fabrication and characteristic of flexible polymer dispersed liquid crystal (PDLC) with Al-doped Zinc Oxide (AZO) layers as transparent conductive electrodes, deposited by magnetron sputtering technique on sheet mica at room temperature. The electro-optical properties, the transmittance of device dependence on the driving voltage.

 

The images of inspected object with projected fringe in the field of depth of focus are recorded by the image sensor array. A band-pass filtering algorithm for mask is presented for the scanning projected fringe profilometry. The mask optimization algorithm helps to identify the amplitude of the projected fringes.

 

PQ-DMNA/PMMA is a new photopolymer which is capable for using red light recording. This work thoroughly explores the possible recording mechanism along with the corresponding modeling and experimental measurements. Finally, a reflective-type PQ-DMNA/PMMA VBG was recorded and successfully served as a diode laser output spectrum narrowing element.

 

This study devotes to minimize the size of digital holographic microscope. It is realized by using a volume holographic optical element to replace the conventional beam splitter. The ideas have been demonstrated by both simulation and experiment.

 

In the paper, we present a method to generating layered three-dimensional (3D) images using the circular iterative angular spectrum algorithm (CIASA) and the experiment results showed the four 2D images successfully constructed a layered 3D. Randomly interleaved sub-DOE method in the CIASA effectively and greatly reduced the image noise.

 

A novel encoder with multiple displacement resolution is developed by integrating a two-grating-scale holographic displacement sensor and a heterodyne interferometer. With suitable arrangement of the measurement system, three effective grating pitches can be obtained. Meanwhile, the optimum resolution of the proposed method can be estimated at 1.42 pm.


 

The effects of initial phase difference on interference patterns of holographic lithography were investigated. Four-beam interference produced patterns with different initial phase difference were simulated with MATLAB software and discussed. The results provide insight for the design of periodic microstructures which would benefits the development and application of holographic lithography.

 

Optical scanning holography (OSH) can record the three-dimensional information of an object, but the viewing angle is usually smaller than one degree because of the large pixel pitch. Here we propose to record a curve hologram by OSH. The viewing angle of curve hologram can be larger than thirty degrees.

 

In this study, we analyze the characteristics on the spatial and temporal domains of a volume holographic optical element(VHOE) which is constructed by interference of spherical waves. We applied the characteristics to dense wavelength-division multiplexing(DWDM) that it can accommodate up to 6400 channels on a VHOE with 1cm2 cross section.

 

An azobenzene-based material is fabricated for holographic storage. With an illumination power approximately 1300mW/cm2, a surface relief grating with diffraction efficiencies approximately 25% can be formed in 20 minutes.

 

This article uses a simple and practical design the CE lens and the addition of an optical zoom system are expected to have a clearer bowel image Based on ZEMAX.