Ushio Denki Kabushiki Kaisha

Tetsuya Ozawa

Takanori Samejima

Yoshihiro Horikawa

Kazuhiro Yoshida

Takayuki Kozakura

Toru Nishikubo

The fundamental wave light emitted from a semiconductor laser is converted in wavelength by a wavelength conversion element and emitted therefrom. A lighting circuit lights the semiconductor laser, and a temperature control unitcontrols the amount of electric power supply to a heater so that the temperature of the wavelength conversion element turns into temperature at which the wavelength conversion efficiency thereof becomes optimal. When a state where the amount of electric power supply of the heater is lower limit or below continues for a predetermined period or longer, the hang-up suppressing unit, or when duration time in a state where the temperature of the wavelength conversion element is higher than the control target temperature becomes higher than a constant value, laser lighting current is decreased by a preset amount, thereby recovery from a high temperature hang-up state performed.

Growing community of inventors

Hyogo, Japan

Tetsuya Ozawa