| 摘要 |
PURPOSE:To prevent the disturbance of signal waveform due to length of wiring by accent the waveform at the end of the image of an object to be measured in a video signal from an image sensor so that it is transmitted to a discriminator section as binary-code video signal of a low frequency. CONSTITUTION:When an amplified video signal VQ' in which a video signal outputted at the end of an object 2 to be measured is accent at the end thereof is outputted and inputted into comparator 14 and 15, it is set at a lower threshold l1 and a higher threshold l2 than the normal amplified video signal and a binary-coded video signals CK(A) and CK(B) are outputted to a latch control section 16. The arithmetic section 20 can calculates a measured value by subtracting the number of clocks DC from the start signal S to the initial end from the number of clocks DD from the start signal S to the final end. The calculation is done each time the final end value latch signal L4 is outputted and as a result of the computation, a data DS is inputted into a data comparison section 11 and the maximum value DM thereof is latched with a maximum value latch 10 to be indicated on a display section 12. This can prevent disturbance of the signal waveform due to the length of the wiring and hindrance by noise or the like. |
