| 摘要 |
PURPOSE:To control the color development of a two-tone color LED package by fixing the region of forward currents for a monochromatic LED light source, alternately lighting two monochromatic LEDs in a time division manner, determining a color arrangement at the rate of a lighting time and obtaining a neutral color. CONSTITUTION:Pulses P1, P2 having mutually reverse polarity are applied to terminals 3, 4, a resistor R3 is selected, and forward currents sufficient for saturating the brightness of monochromatic LED1, LED2 on the ON of a corresponding transistor Q are flowed. Since the waveforms of pulses P1, P2 having predetermined relationship at that time, the LED1 and the LED2 alternately go ON and OFF, but they are viewed as neutral colors. When the periods T2, T3 of waveforms are changed and the rate of the lighting time of two-tone colors is set, proper neutral colors are acquired. When only one element Q is turned ON and forward currents are flowed through the LED, monochromatic light emission is obtained. |
