Phoenix Electric Co., Ltd.

Andrei Kazmierski

Tomihiko Ikeda

Toshitaka Fujii

Kana Watanabe

The light emitting device comprises: a bowl-shaped reflector; a point light source; and a combined lens provided on the light axis of the point light source. And the combined lens has: a convex lens part having a focal point coinciding with the point light source, refracting center light around the light axis into parallel light; and a concave lens part provided around the convex lens part, and refracting and diffusing light having an angle with the light axis larger than an angle between the center light and the light axis so as to increase the angle with the light axis. A virtual focal point of the light refracted and diffused with the concave lens part coincides with the focal point of the paraboloid of revolution.

Light emitting device

A light emitting device comprises: a concave mirror having one focal point; a plurality of main light sources each of which is arranged between the focal point and a light reflection surface of the concave mirror, and emits light toward the light reflection surface; and a plurality of main lenses each of which is arranged between a corresponding one of the main light sources and the light reflection surface, refracts the light emitted from the corresponding main light source toward the light reflection surface, and produces a virtual image of the main light source on the focal point situated at a backside of the main light source.

The light emitting device comprises a point light source, a solid and transparent light guide, a recess arranged on center of a light receiving surface of the light guide, a concave lens formed on a surface of the recess. A reflecting side surface is a revolving surface determined by revolving a parabola passing through one point of peripheral border of the light receiving surface and the other point of peripheral border of the light radiating surface, and having a focal point on the other point of peripheral border. The point light source is arranged apart from the light receiving surface so as to divide the light from the point light source into light entering into the light guide through the surface of the recess and light entering into the light guide through some part of the light receiving surface other than the recess.

There is provided an improved method of lighting an ultra-high pressure discharge lamp in which a pair of electrodes are disposed confronting each other with a spacing of not more than 1.5 mm therebetween in an arc tube forming part of an envelope of quartz glass, the arc tube encapsulating mercury in an amount of 0.15 mg/mm , the method including the steps of: reducing a lamp power supplied to the pair of electrodes to a degree such as not to stop arc discharge in a transition state from a lighting state to extinction; keeping the lamp power thus reduced for a predetermined time period; and shutting down the supply of current to the electrodes.

Growing community of inventors

Himeji, Japan

Andrei Kazmierski