| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a temperature control device capable of holding the temperature of an optical semiconductor element at a fixed value. SOLUTION: The optical semiconductor element 1 is mounted oh a heat conductor 2, a thermistor 11a is arranged on a position of the conductor 2 which is strongly influenced by peripheral temperature as compared with the element 1 and a thermistor 11b is arranged on a position to be weakly influenced by the peripheral temperature as compared with the element 1. A temperature detection circuit 3 consisting of a bridge circuit 30 for connecting the thermistors 11a, 11b so as to constitute a pair of sides and a differential amplifier 31 for inputting non-balance voltage from the bridge circuit 30 detects a difference between the average temperature of two temperature detection points of the heat conductor 2 detected by both the thermistors 11a, 11b and a set temperature and outputs the difference to a temperature control circuit 4, which controls the driving current of a Peltier element 5 so that the average temperature of the two temperature detection points is equal to the set temperature.</p> |
