第20卷
第8期
2012年8月
文章编号
1004-924X(2012)08-1747-07
光学精密工程
Optics and Precision Engineering
集成双光栅于涉微梁位移测量方法
冯金扬，叶雄英，陈烽，商院芳
Vol.20No,8
Aug.2012
（清华大学精密仪器与机械学系精密测试技术及仪器国家重点实验室，北京100084）
摘要：介绍了一种基于集成双光概干涉和CCD图像测量的微梁位移测量方法，并利用相位差约为/2的一组光栅实现了扩量程位移检测，利用表面暂牲层工艺制作敏感芯片，在玻璃基底上刻蚀深度约为人射激光波长1/8的凹槽，凹槽上下的两组光栅与正上方对应的渠分别构成两组相位敏感集成光栅单元。利用1级衍射光将集成光栅单元成像在CCD 靶面上，梁的位移变化通过CCD图像上对应光斑的灰度值变化来反映。实验结果表明，虽然玻璃凹槽腐蚀深度的误差导致光栅之间的相位差偏离=/2，但所制作的集成双光栅结构实现了多周期的扩量程位移检测，通过接近元/2相位差的两个光栅得到的光强信号的错峰使用，避免了干涉法正弦位移检测信号的峰谷不灵敏位置，实验测得微梁的位移变化为 650 nm。
关
词：位移测量；集成双光娠干涉法；图像测量；撤悬臂梁；扩量程
中图分类号：TH744.3;TH822
文献标识码：A
doi;10.3788/OPE.20122008.1747
Interferometricdisplacementmeasurementof microcantileversbased onintegrateddualgratings FENG Jin-yang,YE Xiong-ying', CHEN Feng, SHANG Yuan-fang
(StateKeyLaboratory ofPrecisionMeasurementTechnologyand Instruments,Department ofPrecisionInstrumentsandMechanology,TsinghuaUniversity,Beijing100084,China)
Correspondingauthor,E-mail:ryye@mail.thu.edu.cn
Abstract: A displacement measurement method for microcantilevers based on integrated dual gratings and a CCD image measurement system were presented. The displacement detection range was extend-ed by using two gratings with a phase shift about x/2. The sensor chips were fabricated by surface sacrificial process. Grooves with the depth about 1/8 of the incident laser wavelength were etched on the glass substrate and two adjacent gratings patterned inside and outside of the groove and the reflec tive undersurface of a cantilever formed two phase sensitive integrated gratings, respectively. The in-tegrated grating units formed an image on the CCD sensing surface through the lst order diffraction light, and the gray value change of the light spot was related to the displacement change of the corre sponding cantilever. Experimental results show that although the phase difference between the grat-ings deviates from x/2 caused by the depth errors of the etched grooves, the integrated dual gratings extend the range of displacement detection to multi periods. The insensitive areas at peaks and valleys
收稿日期：2012-04-26；修订日期：2012-06-08.
基金项目：国家自然科学基金资助项目（No，91023027，No.50730009）