Accurate measurement method for the thickness of quartz pendulous reed based on laser vision

The inspection of thickness provides important information about the production process of quartz pendulous reed (QPR) manufacture. Through real-time detection of quartz pendulum reed thickness, high-quality products can be produced, and defective products can be identified and removed. In order to improve detection accuracy and efficiency, a novel non-contact measurement method for measuring the thickness of QPR based on laser vision is presented in this paper, which can realize automatic measurement. Based on the fundamental optics law of Snell, the image of a laser spot is obtained by a laser vision system. An improved edge detection algorithm is proposed to locate the subpixel edge of the laser spot, and the calculation method of the laser spot center is presented. A constant power drive control system of the laser diode and a laser beam alignment system are designed and optimized; and the selection criterion of the laser incident angle is analyzed. Experimental results show that the proposed method has good stability and high measurement accuracy, which can achieve precise non-contact measurement of QPR thickness.