Micromirror With Multiple Digitized Angles for Free Space Optical Crossconnects

To eliminate or lower the power consumption and complexity of the control electronics that limit the applications of analog optical switches, beam steering devices and other micromirrors, this paper presents micromirrors with multiple digitized angles for free space optical crossconnects. Device requirements defined by a dual-lens and dual-micromirror array system are used to guide the designs of the micromirrors. The micromirrors with multiple digitized angles are designed using MUMPs, a MEMS foundry process, and simulated by full coupled-domain FEM/BEM. The effects of the design parameters on the digitized angles are analyzed. These parameters are flexure configuration, connector beam configuration, plate configuration and bottom electrode configuration. With these effects known, a micromirror is successfully designed for the desired optical system. Such a mirror’s repeatability is expected to be about 0.06°, which is obtained by a preliminary experimental study of a similar device. The repeatability of the digital levels highly depends on the initial gap between the mirror surface and the bottom electrode, flexure configuration, connector beam configuration and material properties.