| 摘要 |
<p>PURPOSE:To easily set the comparing level of a comparator and eliminate complicated adjustments, by inputting the comparator output of a differentiation signal into two flip-flops and by setting and resetting a binary coding flip-flop by the output of the two flip-flops. CONSTITUTION:A reflected light signal detected by a sensor 1 is changed into a signal (a) by amplifying it at an amplifier 2, and then, the signal (a) is changed into a signal (b) by differentiating it at a differentiating circuit 3. The signal (b) is compared at the 1st comparator 4 and the 2nd comparator 5, and compared outputs (d) and (e) are obtained from both comparators, respectively. The differentiated signal (b) is once more differentiated at another differentiating circuit 6 on another route and a signal (c) is obtained. The signal (c) is compared at the 3rd comparator 7 and a compared output (f) is obtained. Two D-type flip- flops 11 and 12 are installed and the signals (d) and (e) are used as the reset signal R and the signal (f) and its inverted signal are used as the clock signal C of the flip-flops. Output signals (h) and (i) are used as the set signal S and the reset signal R of a set-reset-type flip-flop 10, respectively.</p> |
