*Mirror cubes on MEMS [#g39f616c]
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Best performance of optical reflector could be found with the dielectric coated glass cube mirror in a thick plate form. It is indeed possible to have such films deposited on a MEMS structure but with a risk of deformed mirror surface due to the intrinsic residual stress. We have newly invented a way of mounting a pair of parallel mirror cubes onto a MEMS electrostatic platform; one of the mirror cube is displaced in a micron scale to tune the optical interference cavity of the Fabry-Perot interferometer. The device is used as a tunable wavelength filter for the WDM (wavelength division multiplex) fiber optic telecom.
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*Wavelength tuning capability [#tb896269]
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By tuning the air gap between the mirror cube, the center wavelength of the transmission is controlled within the 1.55 micron wavelength range. Thanks to the electrostatic comb-drive actuator's performance, the wavelength tuning is pretty linear with the drive voltage.
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*Optomechanical performance [#fb4825ac]
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Despite the surface-to-surface contact between the flat mirrors, the air gap could be easily controlled by the electrostatic actuation without causing permanent stiction. See the following journal report for more information.
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*Reference [#v21e3b08]
+This work has been conducted in collaboration with Koshin Kogaku Co., Ltd., Japan.
+T. Yamanoi, T. Endo, and H. Toshiyoshi,, A hybrid-assembled MEMS Fabry-P´erot wavelength tunable filter, Sens. Actuators A: Phys. (2007), [[doi:10.1016/j.sna.2007.10.080>http://toshi.iis.u-tokyo.ac.jp/toshilab/?plugin=attach&refer=Journal%20Papers&openfile=yamanoi_hybridMEMS.pdf]]
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