| 摘要 |
<p>PURPOSE:To make clear the change of light quantity at the turn-on/off switching point of a stable operation pilot lamp which is used for control of sensitivity of a photoelectric switch and to prevent the setting error of an operating level. CONSTITUTION:The pulse signal of the beam light received by a photodetector 3 is amplified by an amplifier 16 and then compared with the high and low stable operating levels H and L of a window comparator 23. Then the pulse signal higher than the level H or lower than the level L is sent to a latch circuit 27 and then converted into an on/off signal by an integration circuit 30 and a hysteresis circuit 31. Thus an LED driving circuit 26 is operated and a stable operation pilot lamp 25 is turned on.</p> |
