Abstract: In order to solve the problems that HTCC board used in camera module breaks away from the fixed slot,and the subsequent parts are poorly installed,a dislocation detection algorithm of HTCC board based on improved LSD was proposed. Firstly,gamma transform was used to eliminate the shadow on the product image. Then,bilateral filtering was applied to the image. Compared with LSD algorithm,bilateral filtering can keep more complete edge information.Then,a scaling algorithm based on bilinear interpolation and improved mapping relation was proposed to eliminate quantization artifacts and reduce image distortion. Then,a disconnection and reconnection algorithm was proposed to solve the problem of over-segmentation of line segments in LSD algorithm. Finally,based on the improved LSD algorithm,the dislocation detection algorithm of HTCC board was designed,and the number and position of dislocation HTCC board in the product were obtained. The factory verification shows that the average detection time of this method is less than 800 ms,and the detection accuracy is over 97 %. Compared with the traditional LSD algorithm,the detection time is reduced by at least 38 %,and the accuracy is improved by at least 21 %.This method can meet the real-time and accuracy of production.

Key words: LSD algorithm, bilateral filtering, visual inspection, High-Temperature Cofired Ceramic(HTCC)