两种快速测量单模光纤模场半径的方法及装置  

Two methods and devices for quick measuring the mode-field radius of single-mode optical fibers

作　　者：杨高波[1] 徐铁峰[1] 宋玉兰[1] 俞建定[1] 陈征[1] 

机构地区：[1]宁波大学光通信与网络技术研究所,浙江宁波315211

出　　处：《光学仪器》2004年第3期59-63,共5页Optical Instruments

基　　金：国家自然科学基金资助项目(60272034)

摘　　要：介绍两种快速测量单模光纤模场半径的方法及其测量装置——可变孔径法和移动圆孔法;即用步进电机带动在光纤端面远场区域放置的一个透光圆孔屏障移动,或者改变透光圆孔的大小,从而调节PIN管接收到的光强度。用锁相放大器来提高光电信号的信噪比,信号被快速采样后由接口电路输入计算机,自动给出所测单模光纤的模场半径。Two methods and devices which are changeable aperture and movable aperture for measuring the mode-field radius of single-mode optical fibers are presented. A barrier with aperture is placed in far-field area of a fiber, and the source light′s intensity received by PIN tube is adjusted by moving the barrier or changing the aperture-radius with a electromotor. A phase-locked amplifier is used to improve the signal-to-noise ratio of photoelectricity signal, and a computer is utilized to incept the sampling signal and calculate the mode-field radius of fibers quickly.

关 键 词：单模光纤 模场半径 可变孔径 移动圆孔 远场 

分 类 号：TN929.11[电子电信—通信与信息系统]