LIGHT CONTROL DEVICE OF LIGHT-EMITTING DEVICE, AND LIGHT CONTROL METHOD OF LIGHT-EMITTING DEVICE, AND LIGHT-EMITTING DEVICE LIGHT CONTROL PROGRAM

摘要

PPROBLEM TO BE SOLVED: To enable to make a light emitting device emit light at a brightness level corresponding to a duty ratio of a PWM signal by normally operating the light emitting device even when the PWM signal for brightness adjustment having any carrier frequency is input from outside. PSOLUTION: The PWM signals S1, S2 for brightness adjustment to a light emitting diode LD1 are input from outside, the duty ratio R1 of the PWM signals S1, S2 is calculated by measuring them for a prescribed time, a new PWM signal S5 which is adjusted to the most suitable carrier frequency to actuate the light emitting diode LD1 without changing the duty ratio R1 is formed again, and by light emission controlling the light emitting diode LS1 by using this regardless of the carrier frequency of the PWM signals S1, S2 input from outside, the light emitting diode LD1 can be light emission controlled normally by the new PWM signal S5. PCOPYRIGHT: (C)2007,JPO&INPIT