基于声光效应的相干光探测方法的研究  

Research on the Coherent Optical Detection Technology Based on Acousto-optic Effect

作　　者：蒋红艳[1] 何宁[1] 

机构地区：[1]桂林电子科技大学信息与通信学院,广西桂林541004

出　　处：《光电子技术》2009年第3期164-167,共4页Optoelectronic Technology

基　　金：国家高技术研究资助项目(2007AA0860);广西研究生教育创新计划资助项目(2008105950810M416)

摘　　要：基于布拉格衍射和相干光探测原理,分析了入射光和衍射光的特性及数学关系,讨论了如何利用声光偏转器实现信号处理的方法。从改善空间相干光探测效率出发,提出一种将空间光经声光衍射后注入保偏光纤的处理方法,克服了传统相干探测中光偏振态难控制的缺点,减小了外界环境对信号光和参考光合路的影响,降低了光学系统的调整环节中的难度,有效地解决了相干光探测中光束对准和偏振光的保持问题。实验证明,在保证一定的耦合光孔径和激光注入效率条件下,将空间光注入保偏光纤,削弱了背景光对合路产生的影响,使信号光和参考光偏振态和传输方向能更好保持,极大改善了空间相干光探测效率,提高了光电探测信噪比。Based on the principles of Bragg diffraction and coherent optical detection,the mathematical relationship between incident beam and diffractive beam as well as their respective characteristics are analyzed,then how to use acousto-optic deflector to achieve signal processing is discussed.In order to improve the efficiency of the space coherent optical detection,a method which is realized by injecting beam into polarization-maintaining fiber before combining is proposed.Compared with traditional method,it can overcome the shortcoming that polarization is difficult to control.Meanwhile,the influence that the surrounding environment has on the combination of signal beam and reference beam is reduced,and the complexity and difficulty in the process of adjusting optical system are also decreased.Then the problem how to achieve beam alignment and maintain polarization in coherent optical detection is effectively solved.When the coupling optical aperture and laser energy injection efficiency are ensured to meet demands,experiments have shown that,by injecting beam into PM fiber,the impact background light has on combining is weakened to make it easier to keep polarization matching between signal and reference beams,and then the efficiency and SNR of the space coherent optical detection can be greatly improved.

关 键 词：相干光探测 布拉格衍射 激光注入 保偏光纤 

分 类 号：O434.12[机械工程—光学工程]