OPTICAL OUTPUT ADJUSTING DEVICE

摘要

PURPOSE:To improve the control accuracy of an optical output by synchronizing a sample timing of a dimmer pulse of an A/D conversion and a dimmer pulse so as to allow the fluctuation in an optical output not to give effect on the output of A/D conversion. CONSTITUTION:The optical output of a lighting light source B is detected by an optical output detector A and inputted to a dimmer controller E via an A/D converter C. The dimmer controller E feeds a dimmer pulse controlling the optical output to an object value to a dimmer stabilizer F based on an output from the A/D converter C and a set value from an optical output setting value D. The dimmer stabilizer F converts an AC power from an AC power supply G into a high frequency signal in response to the dimmer pulse and supplies the signal to the lighting light source B. A synchronizing means H synchronizes the dimmer pulse with the sample timing of the A/D converter C. Thus, the sample rate of the A/D conversion and the ripple of the optical output are synchronized and even if this ripple is sampled, the effect of the ripple is not given to the sampled value and the control accuracy is improved.