Design of Micromachined Modulator Using Dual Grating

• Main Authors: Chen-Hung Tsai, 蔡振宏
• Other Authors: Jeng-Yang Chang
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/8wqwr4

碩士 === 國立中央大學 === 光電科學研究所 === 94 === Design, fabrication and measurement of variable dual grating will be showed in this paper. In design, we analyze dual grating element by Fourier Optics and G-solver 4.20. We suppose two types of dual grating; Type A is forming by a 0.5 grating with a period �� and π phase depth, the other is same. Type A can be used for variable optical attenuator, which dynamic range is from 48.52% to 0.08%. Type B is forming by a 0.5 grating with period �� and π phase depth, the other is another 0.5 grating with half the period ���}�� and π/2 phase depth. Type B can be used for optical switch by +1 order and -1 order, which the intensity can be modulated from 31.43% to 3.66%. And we suppose a resonant-type dual grating and it can be used for switch of 1550nm and 1310nm. In fabrication, we use semiconductor technology and MEMS technology to fabricate silicon grating and dual grating modulator. In measurement, we use silicon grating to simulate dual grating. Dynamic range of Type A modulate from 19.4% to 1.4%. Type B can be switched from 19.1% to 1.4%. The result of measurement show the change same simulation. In moving of dual grating modulator, comb drive is moving 16�慆 with 130V. The design of dual grating is proved that it can work