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	Large aperture phase-coded diffractive lens for achromatic and 16° field-of-view imaging with high efficiency 期刊论文 OAI收割 Chinese Physics B, 2022, 卷号: 31, 期号: 7 作者: Ma, Gu; Zheng, Peng-Lei; Hu, Zheng-Wen; Ma, Suo-Dong; Xu, Feng \| 收藏 \| 浏览/下载：64/0 \| 提交时间：2022/08/31 achromatic imaging diffractive lens phase coding large aperture high efficiency
	Tunable wavefront coded imaging system based on detachable phase mask: Mathematical analysis, optimization and underlying applications 期刊论文 OAI收割 optics communications, 2014, 卷号: 326, 期号: 0, 页码: 35-42 作者: Zhao, Hui; Wei, Jingxuan 收藏 \| 浏览/下载：25/0 \| 提交时间：2015/03/17 Wavefront coding Detachable phase mask Tunable bandwidth
	Comprehensive performance analysis of popular odd-symmetric phase masks used for wave-front coded imaging system 会议论文 OAI收割 photonics asia 2010, spie, 北京, 2010-10-18~2010-10-21 Zhao H(赵惠); Li YC(李英才) 收藏 \| 浏览/下载：22/0 \| 提交时间：2010/12/09 wave-front coding depth of field odd-symmetric phase masks incoherent imaging system
	Cubic sinusoidal phase mask: Another choice to extend the depth of field of incoherent imaging system 期刊论文 OAI收割 optics and laser technology, 2010, 卷号: 42, 期号: 4, 页码: 561-569 作者: Zhao, Hui; Li, Yingcai; Feng, Huajun; Xu, Zhihai; Li, Qi 收藏 \| 浏览/下载：34/0 \| 提交时间：2010/12/09 Wave-front coding Sinusoidal component Composite phase mask
	Design and image restoration research of a cubic-phase-plate system (EI CONFERENCE) 会议论文 OAI收割 5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies, April 26, 2010 - April 29, 2010, Dalian, China 作者: Zhang J.; Zhang J.; Zhang J.; Shi G.; Zhang X. 收藏 \| 浏览/下载：32/0 \| 提交时间：2013/03/25 Wave-front coding technology is a novel jointly optical and digital imaging technology which can greatly extend the depth of focus of optical systems. The image restoration process is an important part of wave-front coding technology. Using wave-front coding makes the modulation transfer function(MTF) values of the optical systems change little over a range of several times the depth of focus which means the system MTF is quite insensitive to defocus and there is no zero in the passband. So we can design a single filter for the restoration of images in different defocus positions. However it's hard to avoid noise during image acquisition and transmission processes. These noises will be amplified in the image restoration especially in the high frequency part when the MTF drop is relatively low. The restoration process significantly reduces the system signal to noise ratio this way. Aimed at the problem of noise amplification a new algorithm was proposed which incorporated wavelet denoising into the iterative steps of Lucy-Richardson algorithm. Better restoration results were obtained through the new algorithm effectively solving the noise amplification problem of original LR algorithm. Two sets of identical triplet imaging systems were designed in one of which the cubic-phase-plate was added. Imaging experiments of the manufactured systems were carried and the images of a traditional system and a wave-front coded system before and after decoding were compared. The results show that the designed wave-front coded system can extend the depth of focus by 40 times compared with the traditional system while maintaining the light flux and the image plane resolution. 2010 Copyright SPIE - The International Society for Optical Engineering.
	Software radio research of spread spectrum communication system (EI CONFERENCE) 会议论文 OAI收割 2010 International Conference on Computer Application and System Modeling, ICCASM 2010, October 22, 2010 - October 24, 2010, Shanxi, Taiyuan, China Tan Z.-J.; Shi Y.; Zhong Z.-J. 收藏 \| 浏览/下载：25/0 \| 提交时间：2013/03/25 Developing status of software radio is introduced. The configuration of software radio in direct sequence spread spectrum communication system is realized which are composed of the configurations of both transmitter and receiver. The capture and stealth problems of extended coding phase are researched. At last the working status of BPSK and QPSK modulated system is emulated using DSP emulator CCS2.0 and the result is satisfying. 2010 IEEE.
	An image matching algorithm based on sub-block coding (EI CONFERENCE) 会议论文 OAI收割 2nd International Workshop on Computer Science and Engineering, WCSE 2009, October 28, 2009 - October 30, 2009, Qingdao, China 作者: Li S. 收藏 \| 浏览/下载：46/0 \| 提交时间：2013/03/25 In order to improve the speed of matching algorithm and simplify the processing of existing sub-block coding matching a new template matching method combined local gray value encoding matching and phase correlation is proposed. Matching process is divided into rough matching and fine matching. Rough matching divides the image into certain size blocks called R-block sums the gray value of each R-block pixel encodes the R-block according to the gray value distribution of R-block with the adjacent R-block and matches by step between the template and each search sub-image. Then fine matching results are obtained using phase correlation according to initial match parameters. The time complexity of the proposed method is (M2) .The new algorithm is faster than traditional algorithm by two orders of magnitude and the speed has improved twice compared with existing sub-block coding method. Experiments demonstrate that the new algorithm is robust to the linear transformation of pixel grey value and image noise and it also has the stability of small-angle rotation. 2009 IEEE.
	Image compression based on biorthogonal wavelet transform (EI CONFERENCE) 会议论文 OAI收割 ISCIT 2005 - International Symposium on Communications and Information Technologies 2005, October 12, 2005 - October 14, 2005, Beijing, China 作者: Gao Y.; Liu H.; Liu H.; Liu H. 收藏 \| 浏览/下载：39/0 \| 提交时间：2013/03/25 A method for image compression of biorthogonal wavelet transform based on lifting scheme with SPIHT (Set Partitioning In Hierachical Trees) is proposed in this paper. Wavelet transform affords wide space for image coding algorithms because of its excellent space-frequency localization characterizations. The compact supported symmetrical and biorthogonal wavelet has linear phase so it is applied on image compression area widely. The lifting scheme is an efficient method for constructing the wavelet filter after multiresolution. Under the condition of biorthogonal biorthogonal wavelet base can be constructed freely according to the wavelet performance. And it can quicken the implementation speed of the wavelet transform. Analyzing the algorithm of lifting scheme is applying for constructing biorthogonal wavelet. Experimental results indicate that the method of the biorthogonal wavelet that has good performances with SPIHT is applying for image compression so as image synthesis performs well. 2005 IEEE.
	相变存储材料光学特性的超快多阶调制研究学位论文 OAI收割作者: 温帅 \| 收藏 \| 浏览/下载：178/0 \| 提交时间：2018/12/26 相变材料 phase-change material 皮秒激光 picosecond laser pulse 多阶编码 multi-level coding 并行调控 parallel modulation