Share Email Print
cover

Proceedings Paper

An interference signal processing method for displacement measurement by dual wavelength and single grating
Author(s): Guochao Wang; Shuhua Yan; Dongxing Yang; Weihong Zhou; Xuedong Xie
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

Displacement measurement by dual wavelength and single grating integrates the single grating diffraction theory and the heterodyne interference theory. By taking advantage of the two theories, it solves the contradiction between large range and high precision in grating displacement measurement quite well. In order to obtain nanometer resolution and nanometer precision, high-power subdivision of interference fringe must be realized accurately. According to phase demodulation theory for heterodyne interference signal, a digital phase measuring method is proposed by combining frequency-mixing technique and pulse-filling method. The whole signal processing part, which is based on FPGA and PLL, has been designed to realize the integer period measurement and high-powered subdivision of the decimal phase. Through experiments, it is validated that the phase range is [-180°, 180°], and the phase measurement resolution and the phase precision are above 0.03° and 0.1°, respectively. Moreover, the displacement measurement resolution and the displacement precision, corresponding to the phase indexes, are 0.167nm and 0.556nm, respectively.

Paper Details

Date Published: 16 November 2011
PDF: 6 pages
Proc. SPIE 8321, Seventh International Symposium on Precision Engineering Measurements and Instrumentation, 83211A (16 November 2011); doi: 10.1117/12.904076
Show Author Affiliations
Guochao Wang, National Univ. of Defense Technology (China)
Shuhua Yan, National Univ. of Defense Technology (China)
Dongxing Yang, National Univ. of Defense Technology (China)
Weihong Zhou, National Univ. of Defense Technology (China)
Xuedong Xie, National Univ. of Defense Technology (China)


Published in SPIE Proceedings Vol. 8321:
Seventh International Symposium on Precision Engineering Measurements and Instrumentation
Kuang-Chao Fan; Man Song; Rong-Sheng Lu, Editor(s)

© SPIE. Terms of Use
Back to Top