Ushio Denki Kabushiki Kaisha

Yoichiro Higashimoto

Takeo Matsushima

Kiyoyuki Kabuki

Kyosuke Fujina

Yasuro Kikuchi

Toshiyuki Suga

Masashi Nakayama

A short arc discharge lamp has improved starting properties in which there is no danger of damaging the arc tube that surrounds a discharge space and in which the radiant light from the arc tube is not adversely shielded. This is achieved by providing the short arc discharge lamp with a first electrode having an electrical potential and to which a high voltage is applied, and a second electrode opposite the first at a in spaced relationship. Additionally, in the discharge space, there is positioned at least one conductive component with a tip projecting into the discharge space. The conductive component has an electrical potential which is identical to the electrical potential of the first electrode and has a tip spaced a distance from the second electrode which is greater than the distance between the first and the second electrode.

Short arc discharge lamp and light source device

It is an object to provide a xenon discharge lamp lighting device with few or no lamp startup lighting failures, even when a xenon discharge lamp is near the end of its useful life. In the xenon discharge lamp, when a lamp voltage increases, from the ending point of the rush current supply time period, occurring upon starting a xenon discharge lamp lighting igniter, for a preset specified time T, the input power is increased in accordance with the lamp voltage increase amount, whereby constant power control is provided thereafter.

Xenon discharge lamp lighting device

A short arc discharge lamp in which the arc tube contains opposed cathode and anode electrodes with upholding parts that are inserted into a respective glass tube holding cylinder, and in which the glass tubes of the holding cylinders are secured in the side tubes at opposite sides of the arc tube by contracted areas, provides the peripheral surface of the holding cylinders with at least one section of reduced diameter to prevent the holding cylinders from moving, to prevent force from acting in a concentrated manner on the sealed areas and to prevent the lamp from being damaged when the lamp is shaken during transport or the like.

Short arc discharge lamp

A light source device including a short arc discharge lamp having a pair of opposed electrodes within a light emitting bulb of a discharge container, and a concave reflector having an optical axis arranged to coincide with a direction of an arc produced by the electrodes when the discharge lamp is activated. The electrodes are spaced from each other at a distance of 4.0 mm or less and the light emitting bulb has an inner surface and an outer surface which, at least in a specific portion, have substantially spherical surfaces with a center of curvature which is at a center of the arc. The specific portion is located in front of a critical line that passes through the light emitting bulb, the specific portion being an angle having an apex at the center of the arc. The concave reflector has an optical axis that is at least 3 sr in front of a plane which passes through the center of the arc and perpendicular to the optical axis of the concave reflector.

Growing community of inventors

Himeji, Japan

Yoichiro Higashimoto