Profiled Fiber Microlens Technology

Coupling from LD to SMF is a key technology in the field of optical communication and photoelectric instrument. Almost all of optic-fiber systems involve with the coupling question. The outline of fiber's tip has very great influence on the coupling efficiency. It is reported,using the way of grinding and melting to form a microlens on the fiber's tip,can increase fiber's numerical aperture,reduce the ellipticity of laser,and improve coupling efficiency.To get higher coupling efficiency and lower back reflection efficiency is the most direct request to the processing of fiber's tip. In this domestic research field,the special software to help design the microlens is not found,and no experiment device which can draw the picture of infrared laser intensity's distribution in details is worked out,and it is even more in short of the means to appraising coupling performance. So research work is difficult to be deeply carried on.At first,this paper summarizes the developing history of the microlens and looks forward to the application prospect of the fiber microlens. Then explains the theory of couple from LD to SMF in details. Against the several typical microlens models,concrete discussion and analyze are launched. In the course of experiment,we design and set up a microlens test system,which includes several main parts,such as photoelectric detection,signal enlarging,data gathering and analyzing and image processing,etc. This test system has important practical meanings to the research work of LD coupling to optic fiber. It can check the effects of process to fiber's tip,appraise the character of microlens,help us to find out the way to improving coupling efficiency. At last,discuss the processing technology of the microlens,and work out the supplementary software of the test system.