| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an LED lighting device capable of emitting light at a predetermined color temperature. <P>SOLUTION: The LEDs 38R, 38G, 38B in three colors R, G, B as stroboscopic light sources are connected to a main capacitor 44 in series. Each of the LEDs 38R, 38G, 38B is connected with each of transistors 46R, 46G, 46B in parallel, respectively. Pulse signals regulated in duty ratios are applied to the respective transistor 46R, 46G, 46B from a system controller 52, and with these pulses, each of the LEDs 38R, 38G, 38B is made to emit light at a predetermined light quantity ratio, so that the light at a predetermined color temperature is emitted. In this case, a voltage regulating circuit 54 regulates the voltage to be supplied to the LED group 38 so that a constant current is always made to flow through the LED group 38. <P>COPYRIGHT: (C)2004,JPO&NCIPI</p> |
