| 摘要 |
PURPOSE:To attain detection with components having small differences in brightness from the surface color of a substrate by integrating the brightness level difference between a reference substrate and a substrate to be measured within a component area range and comparing the integrated value. CONSTITUTION:A mask pattern stored previously in a memory circuit 10 is read out synchronizing with scans of photographing devices 1 and 2 through a synchronizing signal generating circuit 6 to control integrators 8 and 9. When the mask pattern outputted from the mask pattern memory circuit 10 is 1, video signals from the photographing devices 1 and 2 are integrated, and when 0, the value is held. An adder 3 calculate the level difference between the integrated values, and a decision circuit 4 decides on whether the difference is larger than a specific value or not and sends the result to a latch circuit 7. This decision data is latched at the rising of a frame synchronizing singal and sent out to a controller 5. |
