| 摘要 |
PURPOSE:To make it possible to perform accurate defect inspection simply, quickly and automatically without visual inspection by obtaining a decision value or a refer ence value by statistic processing based on the number of picture elements indicating a nondefective work. CONSTITUTION:The images of a plurality of nondefective works are sensed by use of TV cameras TV1 - TV4 deforehand. The image signals are made to be binary-coded values. The number of the picture elements of the nondefective works is counted. The counted values are statistically processed, and an average value mu and a standard deviation sigma are obtained. The value of mu+ or -3sigma is stored as a decision value. At the time of inspection, the image of a work to be inspected is sensed by use of the same TV cameras TV1 - TV4. The image signal is made to be a binary-coded signal in the binary-coding part of an image processing device 20. The number of the picture elements of the work to be inspected is counted. The counted value of the picture elements of the work to be inspected is compared with the decision value stored in a memory in the decision part of the device 20. When the counted value is out of the decision value, it is decided that the work to be inspected is defective. Thus, the accurate defect inspection can be performed easily, quickly and automatically without visual inspection. |
