Laser based micro alignment for fabrication of highly precise 2D fiber collimator arrays

摘要

In optical communication there are systems requiring a parallel transmission of several high bit rate data channels based on single mode fibers. Especially for a free space transmission within such a system a precise collimation of the parallel channels is necessary to guarantee a low loss system. For this purpose compact two dimensional fiber collimator arrays can be used. A main quality characteristic for these arrays is the pointing accuracy, the angular deviation of the colli-mated beams to a theoretical optical axis. The angular deviation is caused by a lateral offset of the fiber axes to the axes of the corresponding micro lens. To minimize this offset we developed and analyzed an actor geometry for a fiber array which allows a laser based micro alignment of the fibers to the micro lenses. An alignment accuracy within sub microns can be realized which guarantees a pointing accuracy below 0.01 degrees. In this paper we demonstrate some important results of the FEM based analyzes to show the influence of different laser parameters on the actor behavior. Experimental results confirm the results of the FE analyzes and demonstrate the applicability of laser based micro alignment of fibers for the assembly of highly precise two dimensional fiber collimator arrays.