Surface-micromachined free-space micro-optical systems containing three-dimensional microgratings

Free-space micro-optical systems on a chip containing three-dimensional microgratings have been demonstrated using surface-micromachining technique. The micrograting is integrated with a rotary stage, a collimating micro-Fresnel lens, and an edge-emitting laser held by three-dimensional alignment structures on a single Si substrate. Diffraction patterns for various grating rotation angles are observed. Another optical interconnect module consisting of three cascaded microgratings is also demonstrated. The micrograting is a basic building block for many micro-optical systems and is very attractive for applications in microspectrometers, free-space optical interconnect, optoelectronic packaging, and wavelength-division multiplexed integrated micro-optical systems. © 1995 American Institute of Physics.