Silicon Melt Liquid Level Detection Based on Improved Laser Trigonometry

Abstract

In order to improve the robustness of laser triangulation to detect the liquid level of silicon melt, this paper firstly proposes a method of calculating the laser spot coordinates based on the voting mechanism. The vote is taken according to the coordinates of small laser spots, which are formed by the effect of liquid surface fluctuation on the line laser in the liquid level measurement image. Secondly, the Kalman filter method is used to correct the liquid level measurement data and compensate the missing data. Then the linear conversion is performed to obtain the liquid level value. Finally, the experimental results show that this method can effectively improve the robustness of the liquid level measurement by the laser triangulation method, and avoid the generation of impulse noise. The introduction of the Kalman filter can accurately correct the level measurement data and compensate for missing data.