面向微型近红外光谱仪的高效扫描光栅微镜设计（英文）

Design of high-efficiency scanning gratingmirror for near-infrared micro-spectrometer

近年来,随着微光机电系统（MOEMS）技术的快速发展,光谱仪朝着微型化、低成本、高性能方向发展。基于MOEMS技术制作的闪耀光栅可集成于扫描微镜,其作为近红外光谱仪的核心部件,可实现单管探测器代替昂贵的阵列式探测器,以降低近红外光谱仪成本与体积。设计了一种高性能扫描光栅微镜,以提高光谱仪的探测灵敏度。扫描微镜表面集成高衍射效率光栅,背面制作电磁驱动线圈。采用光学软件与有限元方法对器件参数进行优化。仿真结果表明：扫描光栅微镜谐振频率为484.38Hz,最大扭转角度为±4.55°,在800~1800nm工作波长范围内,整体动态衍射效率在54%以上且最大值达90%。

In the last few years, with the rapid development of micro-opto-electro-mechanical-systems（MOEMS）, near-infrared（NIR） spectrometers are moving towards low cost, high performance and miniaturi-zation. As a key component of NIR micro-spectrometers, the scanning grating mirror has an imponderable ad-vantage on diffraction efficiency compared to other grating mirrors, which makes it feasible to develop high opti-cal detecting sensitivity systems with one single photodiode. In order to improve the detecting performance ofNIR spectrometers, a single silicon MOEMS scanning grating mirror has been designed, which integrates a highdiffraction efficiency blazed grating on the top and an electromagnetic actuator on the bottom. Based on a tilted（111） silicon substrate, the scanning grating mirror structure can be easily fabricated by micromachining tech-nology. Meanwhile, a simulation has also been carried out by optical software and finite element analysis（FEA）, and the results show that the dynamic diffraction efficiency is more than 54% and the peak value rea-ches 90% in the spectrum range of 800-1800 nm, meanwhile the maximum torsion angle of MOMES scanninggrating mirror is ±4.55° at the frequency of 484.38 Hz.