Ushio Denki Kabushiki Kaisha

Kazuhiro Yoshida

Takanori Samejima

Takashi Yamashita

Kiyoyuki Kabuki

Yoshihiro Horikawa

Kazuhiro Goto

Kentaro Fujita

Takayuki Kozakura

Nobuhiko Sugihara

Toru Nishikubo

Noriko Horikawa

Tetsuya Ozawa

The wavelength of fundamental wave light emitted from a semiconductor laser is converted by a wavelength conversion element, and the wavelength-converted light is emitted. A power supply circuit feeds electric power to the semiconductor laser. A control part controls an amount of electric power to be fed to a heater such that the wavelength conversion element becomes a temperature that optimizes the wavelength conversion efficiency. Temperatures detected by an element temperature detector and a light source part temperature detector are introduced to the control part, and the control part takes a wavelength conversion element temperature, at which a temperature detected by the light source part temperature detector is minimum, as a set temperature that makes the wavelength conversion efficiency optimal, and feedback-controls the wavelength conversion element temperature such that the wavelength conversion element temperature is at the set temperature by controlling the heating quantity of the heater.

Laser light source apparatus, and method for controlling temperature of wavelength conversion element in laser light source apparatus

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.

Laser light source apparatus

An extra-high pressure discharge lamp, comprises an optical transparent light emitting section, sealing sections connected to the light emitting section, a pair of electrodes which face each other in the light emitting section, wherein one of the electrodes having a thick portion, a thin portion and an intermediate portion which is formed between the thick portion and the thin portion, wherein 0.15 mg/mmof mercury is enclosed in the light emitting portion, and wherein the number of crystal grains which exist on a cross section perpendicular to an axis of the one of the electrodes is three.

Extra-high pressure discharge lamp

Growing community of inventors

Hyogo, Japan

Kazuhiro Yoshida