| 摘要 |
A light-emitting-element lighting circuit for dimming a light emitting element by a PWM dimming signal of a duty ratio corresponding to an input dimming signal is provided. The lighting circuit includes a PWM dimming signal generating unit which generates the PWM dimming signal by performing a summation of AC wave signals including a fundamental wave and harmonics of different frequencies that are integer multiples of a fundamental frequency of the fundamental wave. The fundamental frequency is equal to or higher than a frequency, at which a sound pressure level is at maximum, in an audible frequency range in a correlation spectrum between the sound pressure level generated from the light emitting element and a frequency of an AC wave signal inputted to the light emitting element. |
