| 摘要 |
PURPOSE:To accurately correct the light quantity of a light emitting element by providing a current stabilization means between a D/A converter and the light emitting element and providing a reference voltage stabilization means which stabilizes a reference voltage used for the D/A converter. CONSTITUTION:The current stabilization circuit 103 consisting of an operational amplifier 104, a resistance 105 and a transistor 106 is provided between the D/A converter 101 and an LEDS. Besides, a Zener diode 107 which stabilizes the reference voltage used for the converter 101 is provided. In such a way, the current stabilization means stabilizing a current which is made to flow to the light emitting element is provided and the reference voltage stabilization means stabilizing the reference voltage of the D/A converter is provided, besides. Thus, the light quantity of the light emitting element is accurately adjusted. |
