Study on optical parts of MOEMS optical switch with low insertion loss

We study insertion losses of optical switch when the laser beam is propagating during the free space between two single mode fibers (SMFs) and the related assemblage challenges; Then a new packaging structure is developed for the hybrid-integration of free-space MOEMS (micro-opto-electro-mechanical systems) chip with a silicon micromachined submount to improve alignment accuracy. The submount is designed to accommodate various free-space MOEMS chips with minimal active optical alignment, thus reducing the packaging cost. The silicon submount has a central recess to place the MOEMS chip in, sixteen V-grooves for optical fibers, and micropits for micro ball lenses, all bulk micromachined at the same time by a single anisotropic wet etching step. A corner compensation technique is employed to prevent erosion of the convex corners, where different geometries meet. Through this assembling method, the fiber, micro ball lens can be aligned preciously thus reduced lateral and angular misalignment between them. Then total insertion losses can be decreased.