| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent repeated flashing in illuminance in the vicinity of a threshold value of automatic flashing, make size small, and reduce cost by giving hysteresis to brightness in lighting by the small number of components and brightness in putting lights out. SOLUTION: When a lamp 3 is put out, the potential in a connection point A depends on the resistance values of a CdS 5, a resistance 7, and the lamp 3, and the resistance value of a resistance 6, and when the lamp 3 is lit, since a thyrister 4 is turned on, current does not flow into the resistance 7, and the potential in the connection point A depends mainly on the resistance value of the CdS 5 and the resistance value of the resistance 6. Since on/off of the thyrister 4 is controlled by the potential of the connection point A, hysteresis is given to the brightness in lighting of the lamp 3 and the brightness in putting lights out.</p> |
