Low-cost and efficient coupling technique using reflowed sol-gel microlens

In this paper, we present a novel reflow technique for the fabrication of an elliptical microlens array in sol-gel glass. The fabricated refractive microlens array has a very smooth surface, and structural and dimensional conformity with the designed parameters. It is shown that the microlens array can provide high coupling efficiency of a laser diode to a single mode fiber, and relax the lateral and axial misalignment tolerance. The microlens coupling technique has the advantages of low coupling loss, large misalignment tolerances, and small package volume. (C) 2003 Optical Society of America.