| 摘要 |
<p>Perceived output color and intensity (brightness) of light from a three-element red-green-blue (RGB) light emitting diode (LED) or optical combination of three LEDs (red, green and blue) are controlled with three pulse train signals, each having fixed pulse width and voltage amplitude and then increasing or decreasing the frequency (increasing or decreasing the number of pulses over a time period) of these pulse train signals so as to vary the average current through each of the RGB-LEDs. This reduces the level of electro-magnetic interference (EMI) at any one frequency by varying the pulse train energy spectrum over a plurality of frequencies.</p> |
