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	Design of wideband, high-resolution optical waveform samplers based on a dispersion-flattened highly nonlinear photonic crystal fiber 期刊论文 OAI收割 journal of optics, 2012, 卷号: 14, 期号: 5, 页码: 055201 作者: Liu, Yuanshan; Zhang, Jian-Guo; Zhao, Wei 收藏 \| 浏览/下载：28/0 \| 提交时间：2012/09/04 all-optical sampling photonic crystal fiber four-wave mixing ultrafast optical waveform samplers optical fiber communications
	Physical layer design for free space optical communication (EI CONFERENCE) 会议论文 OAI收割 2012 International Conference on Control Engineering and Communication Technology, ICCECT 2012, December 7, 2012 - December 9, 2012, Shenyang, Liaoning, China 作者: Wang H.; Zhang Q.; Guo J.; Guo J.; Wang H. 收藏 \| 浏览/下载：30/0 \| 提交时间：2013/03/25 A small size Free Space Optical Communication System is introduced including the hardware and the hardware specified physical layer protocol. In detail the rapid synchronization method to reduce the handshake bandwidth requirement is demonstrated. The hardware of the system includes the laser driver system the signal amplifying and shaping system the data interface system. The hardware specified physical layer protocol is used to interface the outer data serialize and deserialize the data stream check transmission errors and schedule the data transmission. The overall system is a FIFO-like system and the user can use it as if he's operating a FIFO. The system is designed mainly for terrestrial FSO link whose signal channel is the atmosphere. Due to the complex composition and activity of the atmosphere this signal channel brings in great influence on the transmitting laser in it for example the absorption and scattering of the atmosphere molecules and aerosols the scintillation of received laser power caused by the turbulence of the atmosphere all of which results in a much higher Bit Error Rate (BER) of the communication system than wired communication systems leading to frequent resynchronization. In our system the sampling clock is generated locally using multi-phase sampling technique rather than PLLbased clock recovery which helps to rapid synchronization. 2012 IEEE.
	Design of driving circuit for binocular CCD image system (EI CONFERENCE) 会议论文 OAI收割 5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optoelectronic Materials and Devices for Detector, Imager, Display, and Energy Conversion Technology, April 26, 2010 - April 29, 2010, Dalian, China 作者: Zhang X.; Zhang X.; Zhang X. 收藏 \| 浏览/下载：42/0 \| 提交时间：2013/03/25 The paper designs a driving circuit of high sensitive wide dynamic and high signal-to-noise ratio for binocular CCD imaging system which adopts a Dalsa-made high resolution full-frame 33-mega pixels area CCD FTF5066M. Inner structure and driving timing of the FTF5066M sensor are presented. Field Programmable Gate Array (FPGA) is used as the main device to accomplish the timing design of the circuits and power driver control of the two sensors. By using the Correlated Double Sampling (CDS) technique the video noise is reduced and the SNR of the system is increased. A 12- bit A/D converter is used to improve the image quality. The output rate of the imaging system designed with integrated chip can reach to 1.3 frames per second through bi-channel. For its good performance low power consumption and small volume the driving system can be applied to aeronautics and astronautics field. With a further improvement a maximum data output rate of 2.7 frames per second can be reached through all the eight channels of the two CCDs. 2010 Copyright SPIE - The International Society for Optical Engineering.
	A design of beam shaping unit for 193nm lithography illumination system using angular spectrum theory (EI CONFERENCE) 会议论文 OAI收割 6th International Symposium on Precision Engineering Measurements and Instrumentation, August 8, 2010 - August 11, 2010, Hangzhou, China 作者: Zhao Y.; Zhang W.; Zhang W.; Li S.; Gong Y. 收藏 \| 浏览/下载：17/0 \| 提交时间：2013/03/25 Off-axis illumination (OAI) technology is widely used to enhance resolution for deep ultraviolet lithography. The realizing methods of OAI include geometrical optics method and physical optics method. However the former has the disadvantage of weak intensity distribution controlling ability and the latter introduces simulation errors evidently when dealing with near field diffraction propagation. A diffractive optical element (DOE) designing method using plane wave angular spectrum theory is presented in this paper. Several kinds of OAI modes at near field away from DOE can be realized and simulation errors and the size of illuminator are also reduced. According to studying the relationships of the sampling point distance of DOE light beam propagation distance and the structure of the beam shaping unit a method of determining the designing parameters is discussed. Using this method several illumination modes are realized and simulation results show that all diffraction efficiencies reach up to 84%. The method of DOE manufacturing is analyzed at last and it is proven to be feasible. 2010 SPIE.