New displacement measurement method based on digital Moiré fringes formed by a single grating

Wu Jian; Yuan Bo; Wang Liqiang

A new method for displacement measurement with a single grating was proposed in the present study. In this method, the magnified grating image was received by image sensor and sent into the computer. Then, the digital Moir fringes were generated by overlaying the grating image with its mirror image, and the Moir fringe pitch was directly subdivided by image sensor pixels, which had a good space consistency. Compared with the traditional displacement measurement method that generated Moir fringes with the superposition of two gratings, this method totally eliminated the interval between two gratings, was easier to assemble and adjust, and had a lower cost for subdivision. The subdivision system with the resolution of 0.04 m, which consisted of the grating with 20 m pitch and the CMOS image sensor with the pixels of 2 0481 536, was tested on the Abbe comparator platform. The results show that the maximum displacement error is less than 0.18 m.

1. State Key Laboratory of Modern Optical Instrumentation,Zhejiang University,Hangzhou 310027,China;

2. CNERC for Optical Instrument,Hangzhou 310027,China

Received Date: 2014-02-08

Rev Recd Date: 2014-03-10

Publish Date: 2014-10-25

Key words:

Abstract: A new method for displacement measurement with a single grating was proposed in the present study. In this method, the magnified grating image was received by image sensor and sent into the computer. Then, the digital Moir fringes were generated by overlaying the grating image with its mirror image, and the Moir fringe pitch was directly subdivided by image sensor pixels, which had a good space consistency. Compared with the traditional displacement measurement method that generated Moir fringes with the superposition of two gratings, this method totally eliminated the interval between two gratings, was easier to assemble and adjust, and had a lower cost for subdivision. The subdivision system with the resolution of 0.04 m, which consisted of the grating with 20 m pitch and the CMOS image sensor with the pixels of 2 0481 536, was tested on the Abbe comparator platform. The results show that the maximum displacement error is less than 0.18 m.

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Reference (9)

[1]	Yuan Bo, Yan Huiming, Cao Xiangqun. A new subdivision method for grating-based displacement sensor using imaging array [J]. Optics and Lasers in Engineering, 2009, 47(1):90-95.
[2]
[3]
[4]	Sun Lei, Zhang Zhili, Tan Lilong, et al. Denoising method of dynamic grating Moir signal based on wavelet threshold [J]. Infrared and Laser Engineering, 2010, 39(3): 576-580.(in Chinese) 孙磊,张志利,谭立龙, 等. 采用小波阈值的时变光栅莫尔信号去噪方法[J]. 红外与激光工程, 2010, 39(3): 576-580.
[5]	Yang Dongxing, Yan Shuhua, Du Liebo, et al. Design of a miniature single-grating displacement measuring system with nanometer resolution [J]. Infrared and Laser Engineering, 2013, 42(4): 1020-1025. (in Chinese) 杨东兴,颜树华,杜列波,等. 一种小型化纳米级单光栅位移测量系统的研制[J]. 红外与激光工程, 2013, 42(4): 1020-1025.
[6]
[7]
[8]	Sun Mingjie. Research on CCD subdivision technology for Moir fringe of grating [D]. Shenyang: Shenyang University of Technology, 2012. (in Chinese) 孙杰明. 光栅莫尔条纹CCD细分技术研究[D]. 沈阳: 沈阳工业大学, 2012.
[9]	He Pin, Hua Yanhong, Li Zhen. Design and application of GWC100-3 grating displacement sensor [J]. Manufacturing Technology Machine Tool, 2012(1): 52-54. (in Chinese)

New displacement measurement method based on digital Moiré fringes formed by a single grating

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