| 摘要 |
PROBLEM TO BE SOLVED: To provide a device for inspecting a solder joint that can enhance the accuracy of determining whether or not the solder joint is defective. SOLUTION: An approximate expression computing means plots the boundary (binarization boundary) of a recess of a white area on xy coordinates. The x-axis and the y-axis correspond respectively to the vertical and horizontal sides of a digital image. The approximate expression computing means approximates each point of the binarization boundary as shown by the full line, using a secondary approximate expression shown by the chain line. Based on whether the secondary approximation coefficient of the secondary approximate expression computed by the approximate expression computing means is positive or negative, a determining means determines whether the white area is projecting or recessed. For example, when the secondary approximation coefficient is positive, the shape of the fillet of solder is recessed, which is proper. The determining means also determines the sharpness of the shape of the fillet of the solder based on the magnitude of the absolute value of the secondary approximation coefficient. |
