Realization of novel monolithic free-space optical disk pickup heads by surface micromachining

A novel monolithic free-space optical disk pickup head has been fabricated by micromachined micro-optical bench technology. The pickup head contains a self-aligned semiconductor edge-emitting laser, a collimating lens, a beam splitter, two focusing lenses, and two 45 degrees mirrors. All optical components are built monolithically on Si substrates. The 45 degrees mirror directs the optical output beam in the surface-normal direction. This novel design could signif icantly reduce the size and the weight of the optical pickup head as well as the cost of the assembly processes. The weight reduction could also greatly increase the data access rate.