| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical controller which can cause a quantity of light to reach a target value swiftly upon a startup of energization of a drive current, and can execute a stable control after the quantity of light has reached the target value. SOLUTION: When the quantity of light (monitor voltage) of a laser diode is less than a fixed level, the drive current is controlled based on an updated one monitor voltage. For this reason, the quantity of light can be caused to reach the target value swiftly. When the quantity of light is equal to or more than the fixed level as shown in Fig. 6, an average value of four monitor voltages is construed as a control value. For this reason, after the quantity of light has reached the target value, a stable control is possible. Moreover, in this case, as the control value is varied at each time the four monitor voltages are read in, the stabler control is possible. Further, in this case, as the four monitor voltages are read in as a read time is shifted everyΔT, influences of a fluctuation of the monitor voltages can be dispersed. COPYRIGHT: (C)2008,JPO&INPIT
|
