Study of laser sensor for sub-micron displacement measurement

• Main Authors: Kung, Chia-Chen, 龔家楨
• Other Authors: Su, Kuan-Wei
• Format: Others
• Language: en_US
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/91025914715440117069

碩士 === 國立交通大學 === 電子物理系所 === 98 === The purpose in this study is to design a laser triangulation displacement sensor with high speed about 20 kHz and resolution up to sub-micron class, which can be applied to inspection in the industry by describing one dimension profile. We study principle of triangulation to improve the resolution and correct the optical aberration with aperture. To use beam expander and focus lens with analysis of laser feature gets smaller spot diameter which raises precision. Diode pumping solid state laser has fine output mode and power modulation and image sensor possesses the characteristic of low noise and high sensitivity. Integrate them into displacement measurement system. For poly-silicon surface displacement, we propose optimization centroid algorithm to achieve sub-micron resolution and fast sampling speed with the measurement system.