A Novel Method for LCD Module Alignment and Particle Detection in Anisotropic Conductive Film Bonding

Autor: Tengyang Li, Feng Zhang, Huabin Yang, Huiyuan Luo, Zhengtao Zhang
Jazyk: angličtina
Rok vydání: 2023
Předmět:
Zdroj: Machines, Vol 11, Iss 1, p 49 (2023)
Druh dokumentu: article
ISSN: 2075-1702
DOI: 10.3390/machines11010049
Popis: In this paper, we propose a misalignment correct method and a particle detection algorithm to improve the accuracy in the quality inspection of the LCD module after the anisotropic conductive film (ACF) bonding. We use only one camera to acquire images of multiple positions in order to establish the transformation from the image space to the world coordinate. Our method can accurately determine the center of rotation of the carrier table and calculate the deviation of position and angle of the tested module. Compared to traditional ways that rely on multiple cameras to align the large-sized product, our method has the advantages of simple structure, low cost, and fast calibration process. The particle detection is performed after positioning all bumps of the bonded module. The gray morphology-based algorithm is developed to detect the extreme point of every particle and refine the particle result through blob analysis. This method reduces the over-checking rate and performs better on the detection precision for dense particles. We verify the effectiveness of our proposed methods in our experiments. The alignment error can be less than 0.05 mm, and the accuracy of the particle detection is 93% while the recall rate is 92.4%.
Databáze: Directory of Open Access Journals