Chinese Optics Letters, 2004, 2 (6): 06328, Published Online: Jun. 6, 2006
Double sinusoidal phase modulating laser diode interferometer for thickness measurements of transparent plates Download: 612次
Abstract
A double sinusoidal phase modulating (SPM) laser diode interferometer for thickness measurements of a transparent plate is presented. A carrier signal is given to the interference signal by using a piezoelectric transducer, and the SPM interferometry is applied to measure the thickness of a transparent plate. By combining the double-modulation technique with the Bessel function ratio method, the measurement error originating from light intensity fluctuations caused by the modulation current can be decreased greatly. The thicknesses of a glass parallel plate and a quartz glass are measured in real time, and the corresponding experimental results are also given.
Dailin Li, Xiangzhao Wang, Yingming Liu. Double sinusoidal phase modulating laser diode interferometer for thickness measurements of transparent plates[J]. Chinese Optics Letters, 2004, 2(6): 06328.