Patent ID: 7848373
Filing Date: 2010-12-07
Classification: H01S

Abstract:
1. A drive circuit for a semiconductor light emitting element used for a light source device adapted to output a laser beam converted using a wavelength conversion element adapted to generate a second harmonic wave, comprising: a switching element connected to a power supply; an inductor having one end connected to the power supply via the switching element, and the other end connected to the ground; a first terminal disposed between the switching element and the inductor, to which a cathode terminal of the semiconductor light emitting element is connected; and a second terminal disposed between the other terminal of the inductor and the ground, to which an anode terminal of the semiconductor light emitting element is connected, only the switching element, the inductor and the cathode terminal of the semiconductor light emitting element being connected to the first terminal; wherein a resistor element connected to a point between the inductor and the semiconductor light emitting element; wherein a capacitor having first and second terminals, the first terminal of the capacitor being connected between the power supply and the switching element and the second terminal of the capacitor being connected to a ground potential; wherein a switch drive circuit adapted to supply the switching element with a waveform signal having a predetermined duty ratio with which the switching element is driven.