| 摘要 |
PURPOSE:To detect the surface detects of objects accurately and easily by delaying the delay signals obtained by delaying electric signals by at least one scanning, further with plural stages of delay elements, adding and averaging the outputs of the respective delay elements, and comparing the electric signals under scanning with the added and averaged signal. CONSTITUTION:The electric signal E1 from a photoelectric converter 100 is amplified with an amplifier 101 which outputs a video signal E2. The signal E2 is inputted to a comparator 103 and a delay circuit 104. The circuit 104 is constituted by cascade connection of (n) pieces of delay elements d1-dn. One piece of the element di (i=1-n) can delay the signal E2 by as much as one scanning from the current rotary slit to the next rotary slit. The signal E2 is delayed by as much as (n) scanning with the delay circuit 104. The delay signal F via the circuit 104 is further inputted to a delay circuit 105 and total N pieces of delay signals G1-GN are drawn out individually from N pieces of delay elements D1-DN, and are inputted to an adder 106. The adder 106 adds the received signals G1-GN, and outputs the average value thereof from its output part. The output is inputted to a comparator 103, whereby the influence upon the average value signal is decreased and fine defects are detected. |
