| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To output a desired color to a variable color illuminator by surely gradation-driving each light emitting diode even when forward voltages of the diodes of the respective colors are different. <P>SOLUTION: The gradation signals of the respective colors output from a D/A converter 35 are converted into drive signals and input to digital transistors 53 to 55. The conductivities of the transistors 53 to 55 are changed with a drive signal, and drive currents are supplied to the light emitting diodes 11 to 13. Here, resistors 56 to 58 set maximum currents of the diodes 11 to 13, resistors 59 to 61 supply drive currents according to the drive signals to the diodes 11 to 13 even when the signals are the maximum. <P>COPYRIGHT: (C)2003,JPO</p> |
