Microelectromechanical systems (MEMS) integrate electrical and mechanical components on a single substrate, such as silicon, using microfabrication technologies. Typically, the electrical components are fabricated using integrated circuit processes, while the mechanical components are fabricated using micromachining processes that are compatible with the integrated circuit processes.
MEMS devices are found in an increasing number of applications, from sensor technology, to biomedicine, to telecommunications. Presently, some of the most interesting applications for MEMS devices are optical applications, wherein the tiny mechanical components include mirrors, prisms and/or gratings. For example, in the area of telecommunications, MEMS are used in optical switches, optical modulators, optical attenuators, and optical filters.
In many optical MEMS devices, the MEMS structures are actively aligned using a dithering technique that introduces intentional alignment errors. While this technique has been proven valuable when there is a small range of MEMS orientations, there are more challenges if a wider range of MEMS orientations is required. In particular when the range is relatively wide, the difference in actuation energy for MEMS structures at opposite ends of the range is quite large. This non-linearity, which for example can be caused by electrostatic actuation of MEMS, is translated through the dither into gain distortions that negatively affect the MEMS control system and/or produce undesirable optical distortions (e.g., a perceivable optical dither).
It is an object of the instant invention to provide a method and system for providing gain normalization in a MEMS control system and/or MEMS device.