Open AccessMulti-beam laser heterodyne measurement with ultra-precision for the glass thickness based on oscillating mirror sinusoidal modulation
Author(s) -
Yanchao Li,
Chunhui Wang,
GuiLu Long,
Huan Cong,
Qi Yang
Publication year - 2012
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.61.044207
Subject(s) - heterodyne (poetry) , optics , demodulation , laser doppler vibrometer , materials science , laser , beam (structure) , signal (programming language) , modulation (music) , heterodyne detection , harmonic , doppler effect , frequency modulation , physics , laser beams , acoustics , radio frequency , computer science , telecommunications , channel (broadcasting) , astronomy , programming language
In this paper, We propose a novel method of measuring glass thickness by means of multi-beam laser heterodyne. Based on the Doppler effect and the heterodyne technology, loading the information about the glass thickness into the frequency difference of the multi-beam laser heterodyne signals by sinusoidal frequency modulation of the oscillating mirror that is in a simple harmonic motion, we can simultaneously obtain many values of the glass thickness through the multi-beam laser heterodyne signal demodulation. Processing these values by weighted-average, the glass thickness can be obtained accurately. This novel method is used to simulate the measurements for different glass thicknesses by MATLAB, the obtained result shows that the relative measurement error obtained by using this method is just 0.008%.