| 摘要 |
PURPOSE:To make inspection quick and reliable by a method wherein a light pattern changing in a plurality of phases is applied to a printed circuit board, the position, area, etc. of cream solder are detected from a plurality of image signals and detected data are compared with reference data. CONSTITUTION:A controller 9 sends a signal to an illumination controller 6 and makes an illuminating device 2 start application of stripe-shaped illumination, while making it shift the phase of the pattern by a 1/4 pitch and change it over sequentially. A CCD camera 3 picks up an image of inspection area in each illumination and outputs image signals for four picture frames sequentially. An image memory 8a stores the image signals sequentially. A computer device 5 calculates the height of a reflecting surface of each part on the basis of the four image signals by a phase shift method. Based on the data on the height, a printed region of cream solder 10a being higher than the plane of a printed circuit board 10 is detected and the position and the area thereof are determined. The height of each part is integrated and thereby the amount of the solder 10a is calculated. Each data thus determined are compared with reference data and it is determined thereby whether a printed state of the solder 10a is good or bad. |
