| 摘要 |
PURPOSE:To identify front and back of a measuring object simply without touching the object by comparing a value obtained through white or black level area calculating unit with a value set on a reference area calculating unit for the front or back side on a comparing unit. CONSTITUTION:A measuring object is imaged by a photoelectric scanner 1, an output video signal is binary-coded through a binary circuit 2 at a black-and-white center level, and an analog signal is converted to a digital signal. The binarycoded signal is subjected to OR operation with an output signal of a sampling pulse oscillator 32 through a gate circuit 31 of an area calculating unit 3, and a white portion is converted to a pulse number and digitized on a counter 33. At a reference area setting unit 4, an intermediate value of the area of a white portion of the front side pattern and the back side pattern is set in pulse number through conversion, which is compared with the value digitized on the counter 33 of a calculating unit 3 on a comparing unit 5, thus outputting a back side identified signal to an output end 52. |
