| 摘要 |
<P>PROBLEM TO BE SOLVED: To perform temperature compensation of a photodetector. <P>SOLUTION: Light from a photodiode 10 is detected by a phototransistor 12. An operational amplifier (light reception quantity detection means) 36 converts a detection current flowing in the phototransistor into a detection voltage according to a light reception quantity to detect the detection voltage, and compares the detection voltage with a reference voltage detected at light reception of reference light quantity to detect fluctuation in the light reception quantity. A controller 60 detects a temperature on the basis of a forward drop voltage of the photodiode 10, and controls a current of the photodiode 10 on the basis of the temperature to correct the detection voltage, and thereby to perform temperature compensation of the detection voltage. <P>COPYRIGHT: (C)2013,JPO&INPIT |
