| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a light emitting device at a low cost that can surely detect a change in temperature in an LED and make the LED emit a light efficiently. <P>SOLUTION: An LED driving circuit 12 is provided with a voltage measuring circuit 14 for measuring the drive voltage of an LED 11, a drive current control circuit 15 for controlling a drive current, a driving DC 16 as a power supply for driving the LED 11, and an computation control unit 17. The computation control unit 17 serially acquires voltage values measured by the voltage measuring circuit 14 and calculates a quantity of voltage change per unit time, and it controls the drive current control circuit 15 on the basis of the calculated values to regulate the drive current of the LED 11. Thus, the temperature of the LED 11 can be controlled. <P>COPYRIGHT: (C)2005,JPO&NCIPI</p> |
