| 摘要 |
PURPOSE:To prevent the reduction in luminous quantity over every frequency by providing a high frequency emphasis circuit including a resistor and a capacitor to a voltage/current conversion means provided on an electrooptic conversion means at the sending side. CONSTITUTION:A voltage/current converter 22 as a voltage/current conversion means consists of an operational amplifier 11, a transistor (TR) 13 and resistors 14, 15 and 16. A resistor 17 and a capacitor 18 are connected between a power supply 21 and an emitter of the TR 13 in series to form a high frequency emphasis circuit 23. The high frequency emphasis circuit 23 in the voltage/current conversion means 22 converts a voltage into a current while the frequency characteristic at a high frequency is emphasized. That is, the frequency characteristic of the voltage/current conversion is varied by having only to adjust the resistor and the capacitor in the high frequency emphasis circuit 23. |
