| 摘要 |
PURPOSE:To accomplish adjustment of quantity of light with a limited heat loss by means of a charge/discharge transistor circuit which allows the setting of charging time constant for capacitors as desired. CONSTITUTION:With adjustment of a variable resistance 5a, the charging time constant for capacitors 5b is regulated so that the conduction cycle for the control transistor 5 is set as desired. The output is applied to a drive transistor 4 through an amplification transistor 7 to control the amount of current to the light source for illumination. With such an arrangement, the adjustment can be made for the quantity of light without generation of heat. |
