Code counting of optical fringes: methodology and realization.
A new optical fringe-counting method that entails coding interference fringes is proposed. This method features not only the implementation of reliable bidirectional optical fringe counting but also the accurate counting of oscillating optical fringes. Its main merit is the achievement of a higher phase resolution, lambda/16 (lambda, wavelength), as opposed to lambda/8 of earlier fringe-counting methods. The robustness of fringe-code counting with regard to relative phase variations in the sine and cosine interference signals constitutes another merit of this method. The principle and realization circuit of the fringe-code-counting method are described in detail, and the experimental results with a resolution of lambda/16 are presented to show the feasibility of this method.
Chen
Benyong
B
Department of Measurement and Control Technology, Zhejiang University of Sciences, Hangzhou 310018, China. chenby@zist.edu.cn
Luo
Jianbo
J
Li
Dacheng
D