| 摘要 |
<p>PROBLEM TO BE SOLVED: To correct the brightness and colors by controlling a duty ratio of switching circuits on the basis of a standard length of an on-time set by a standard on-time setting circuit to control the lighting of light emitting diodes. SOLUTION: The characteristics of a plurality of diodes generating the lights of three primary colors, are ranked in the manufacturing, and the ranks are set to jumper wires J1-J8 of a standard on-time setting circuit. This circuit determines a standard length of the on-time for controlling a duty ratio of switching circuits consisting of switching circuits for each color on the basis of the set rank information. The on-time for lighting the light emitting diodes of the duty ratio corresponding to the ranking is input to the switching circuits and the desired outputs are obtained from a plurality of light emitting diodes. Accordingly, the brightness and colors can be corrected in the circuits capable of controlling the colors on the basis of the control of the duty ratio of the light emitting diodes.</p> |
