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Wang Y.,Anhui University | Shen C.,Anhui University | Zhang C.,Anhui University | Zhang C.,Key Laboratory of Modern Imaging and Displaying Technology of Anhui Province | And 2 more authors.
Zhongguo Jiguang/Chinese Journal of Lasers | Year: 2012

Color holographic display is an important goal of holographic display research. Color holographic display technology using RGB lasers is studied, and color holographic display method based on space division multiplexing is proposed. Both the size and center of holographic optoelectronic reconstruction image depend on the wavelength of RGB lasers. The method by adjusting the original sizes of the RGB components of color images and adding digital blazed grating to achieve the coincidences of the sizes and centers of RGB reconstructed images is proposed. The color holographic display system with space division multiplexing method is developed, and hologram generated by 24-bit computer is added to spatial light modulator to reconstruct the color images by the advanced physics setup. Experimental results demonstrate the feasibility of the method proposed.


Zhang C.,Anhui University | Zhang C.,Key Laboratory of Modern Imaging and Displaying Technology of Anhui Province | Cheng H.,Anhui University | Zhang F.,Anhui University | And 2 more authors.
Tien Tzu Hsueh Pao/Acta Electronica Sinica | Year: 2014

Super resolution (SR) is being considered as one of the “holy grails” of optical imaging and image processing. Different from the registration error and costly problem faced in multiple subpixel image registration fusion method to achieve super-resolution, this paper introduces the compressive sensing theory into super-resolution imaging, which benefit from the general sparse representation of most nature images, and proposes a novel single-exposure frequency-domain amplitude encoding compressive imaging method. Exploiting the 4-f Fourier optics architecture for modulating the image information by the 0/1 amplitude randomly in the frequency domain, low-resolution CCD device can then be used to records the corresponding measured values by integral downsampling and finally apply optimization methods to reconstruct the original high-resolution images from small number of measured values. Simulation experiments demonstrate that the 2D image information can be effectively acquired and reconstruction from the measured data by our proposed method. In addition, our method can effectively deal with large-scale image compressive imaging problem and thus has an important application prospects.


Zhang C.,Anhui University | Zhang C.,Key Laboratory of Modern Imaging and Displaying Technology of Anhui Province | Shen C.,Anhui University | Cheng H.,Anhui University | And 3 more authors.
Zidonghua Xuebao/Acta Automatica Sinica | Year: 2015

Compressed holography is an emerging 3D reconstruction technique, which bridges the gap between compressed sensing (CS) theory and Gabor's holography, especially for rebuilding 3D objects from a single-frame 2D holography measurement data. In this paper, the single-wavelength settings in compressed holography are extended to the multi-wavelength, and an improved compressed color holography imaging method is proposed, and a compressed measurement model in multi-wavelength case is established. Utilizing sparse prior knowledge of an object, a multi-wavelength 3D object can be reconstructed effectively from single-frame 2D color holography data of the object, so as to suppress the twin image and the defocus image due to multilayer slices and thus improve high quality reconstruction. Numerical results have demonstrated the effectiveness of our method. Copyright © 2015 Acta Automatica Sinica. All rights reserved.


Zhang C.,Anhui University | Shen C.,Anhui University | Cheng H.,Key Laboratory of Modern Imaging and Displaying Technology of Anhui Province | Zhang F.,Anhui University | And 3 more authors.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2015

In classical compressive holography (CH), which based on the Gabor holography setup, two nonlinear terms are inherent in the intensity recorded by a 2D detector arrays, the DC term and the squared field term. The DC term (the term at the origin) can be eliminated by filtering the Fourier transform of the interference irradiance measurements using appropriate high-pass filter near the zero frequency. The nonlinearity caused by the squared field term can be neglected and modeled as a error term in the measurement. However, the above assumptions are significantly limited, which yields the degradation of reconstruction quality. In this paper, an novel scheme using phase-shifting method is presented. To accurately recover the complex optical field caused by the propagation of the object, without the influence of the DC term and the squared field term, a very effective method for removing these two terms is introduced. The complex optical field of the 3D object and the complex optical field at the detector plane can be precisely represented by a linear mapping model. The complex optical field at the recorder plane is obtained by phase-shifting interferometry with multiple shots. Then, the corresponded complex optical field at the detector plane can be successfully extracted from multiple captured holograms using conventional four phase-shifting interferometry. From such complex optical field at the record plane, including the amplitude and phase information, the complex optical field of the 3D object can be reconstructed via an optimization procedure. Numerical results demonstrate the effectiveness of our proposed method. © 2015 SPIE.


Zhang C.,Anhui University | Cheng H.,Anhui University | Cheng H.,Key Laboratory of Modern Imaging and Displaying Technology of Anhui Province | Shen C.,Anhui University | And 2 more authors.
Dianzi Yu Xinxi Xuebao/Journal of Electronics and Information Technology | Year: 2012

Compressive imaging is a novel imaging method based on compressive sensing theory, the key idea is that it can reconstruct original scene precisely with far fewer measurements than Nyquist samples if the scene is sparse/compressible; Constructing an appropriate measurement matrix easy to realize random linear measurement of an image is one of the key points of practical compressive sensing. In this paper, analyzing the existing Bernoulli and Circulant matrices, a novel sparse trinary circulant measurement matrix with random spacing for phase mask is proposed. Simulation results show that novel phase mask matrices, compared to Bernoulli and Bernoulli-Circulant (BC) phase mask matrices, have the same signal-to-noise ratio; But with the number of independent random variables and the number of non-zeros entries a dramatically reduction, which is more conducive to data transmission and storage; more importantly that is easy to hardware implementation and the reconstructed time is only about 20%~50% of that of original matrices, which has a significance effects on practical compressive sensing.

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