*Assymetrically Driven Electrostatic Parallel Plate for Tilt Mirror [#y5f91742]
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Variable optical attenuators (VOAs) are used everywhere in the wavelength-division-multiplex (WDM) fiber optic network. VOAs are used to adjust the optical intensity of each wavelength component traveling in a single optical fiber such that signal pulse shape woud not suffer from fiber's dispersion.
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By using the MEMS technology, we have developed a very reliable VOA in collaboration with a fiber optic component company Santec Co., Japan. The VOA is made of an SOI wafer with double-side DRIE processes. The mirror in the middle is 0.6 mm in diameter and suspended with a pair of torsional hinges. There is a shaped cut on the backside of the mirror part and is used as a counter electrode for electrostatic operation. Typical driving voltage is 5 to 12 V for optical attenuation level of as large as 40 dB. The VOA can survive mechanical shock of 500 G or higher, and has mechanical tolerance of up to 50 G without causing optical intensity fluctuation of +/- 1 dB.
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*VOA Performance [#j0af952b]
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*Reference [#a2737d11]
+Keiji Isamoto, Atsushi Morosawa, Masataka Tei, Hiroyuki Fujita and Hiroshi Toshiyoshi, "A 5-volt operated MEMS variable optical attenuator by SOI bulk micromachining," IEEE J. Selected Topics in Quantum Elec (JSTQE), March, 2004.
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+Keiji Isamoto, Atsushi Morosawa, Masataka Tei, Hiroyuki Fujita and Hiroshi Toshiyoshi, "MEMS Variable Optical Attenuator using Asymmetricaly Driven Paralle Plate Tilt Mirror," IEEJ Trans. SM, vol. 124, No. 6, 2004, pp. 213-218 ([[in Japanese:http://toshi.fujita3.iis.u-tokyo.ac.jp/toshilab_j/index.php?cmd=read&page=%C8%AF%C9%BD%CF%C0%CA%B8%A1%CA%C6%FC%CB%DC%B8%EC%A1%CB&word=%C8%F3%C2%D0%BE%CE%B6%EE%C6%B0%CA%BF%B9%D4%CA%BF%C8%C4%B7%BF%A5%C1%A5%EB%A5%C8%A5%DF%A5%E9%A1%BC%A4%F2%CD%D1%A4%A4%A4%BFMEMS%B2%C4%CA%D1%B8%F7%B8%BA%BF%EA%B4%EF]]).
+[[Catalog page at manufacturer:http://www.santec-net.co.jp/products/components.html]]
+http://www.santec.com/products/index.htm
Chunichi Sangyo Gijutsu Sho 2004 was awarded to this work [#p4964b8b]
//[[Chunchi News Paper article on Dec. 20, 2004>http://toshi.fujita3.iis.u-tokyo.ac.jp/toshilab/index.php?plugin=attach&openfile=santecVOAawarded.jpg&refer=MEMS%20Variable%20Optical%20Attenuator%20with%20Parallel-Plate%20Tilt%20Mirror]]
//[[&ref(chunuchi.gif,nolink,50%);>http://www.chunichi.co.jp/sangisho/industry.html]]
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