Abstract: A method of lighting a high-pressure discharge lamp is configured to change a power to be supplied to the high-pressure discharge lamp in accordance with a luminance parameter of an image content. The method includes switching between a low temperature operation and a high temperature operation so as to maintain a condition that mercury encapsulated into an arc tube part of the high-pressure discharge lamp constantly partially deposits without evaporating. The low temperature operation is performed where the temperature in the arc tube part is less than or equal to the deposition temperature of the mercury, whereas the high temperature operation is performed where the temperature in the arc tube part is greater than the deposition temperature of the mercury.

Abstract: It is an object of the present invention to provide a lighting circuit for and a lighting method of a high-pressure discharge lamp whereby remarkable reduction in illuminance maintaining rate can be avoided by reducing variation in inter-electrode distance in the beginning of usage without modulating a lighting frequency. The object can be achieved by a lighting circuit configured to light a high-pressure discharge lamp by supplying an alternating lamp current, which includes at least one pulse current superimposed on the former half of each half period of a base lamp current and at least two pulse currents and superimposed on the latter half of each half period, to the high-pressure discharge lamp.

Abstract: It is an object of the present invention to provide a lighting circuit for and a lighting method of a high-pressure discharge lamp whereby remarkable reduction in illuminance maintaining rate can be avoided by reducing variation in inter-electrode distance in the beginning of usage without modulating a lighting frequency. The object can be achieved by a lighting circuit configured to light a high-pressure discharge lamp by supplying an alternating lamp current, which includes at least one pulse current superimposed on the former half of each half period of a base lamp current and at least two pulse currents and superimposed on the latter half of each half period, to the high-pressure discharge lamp.

Abstract: An LED lamp comprises: a first LED part, a second LED part that is connected to the first LED part in parallel and is configured to emit a light with a color temperature lower than that of a light to be emitted from the first LED part, and an impedance circuit that is connected to the first LED part in parallel while being connected to the second LED part in series.

Abstract: A light emitting device comprises: a surface light source for a surface-emission; a CPC lens having a light receiving surface, a side reflective surface, and a light emitting surface, the light receiving surface receiving a part of light from the surface light source, the side reflective surface reflecting the light from the light receiving surface, and the light emitting surface facing the light receiving surface and emitting the light; and a reflector containing the surface light source and the CPC lens, and having a concaved reflective surface for reflecting forward the light deviating the light receiving surface from the surface light source, wherein a ratio of a illumination area of the surface light source to an area of the light receiving surface of the CPC lens is not less than 0.63 and not more than 2.93.

Abstract: [Object] To provide a light source device which allows the lighting starting properties of a high-pressure discharge lamp to be reliably improved without increasing the entire length of the light source device and exposing an auxiliary lamp to the outside. [Solution] A light source device 10 includes: a high-pressure discharge lamp 12; a bowl-shaped reflector 16 having an insertion hole 44 which is formed in a bottom portion 16a and in which a sealing portion 24 is inserted, an inner space 46, and a reflection surface 48 formed on an inner surface thereof; an auxiliary lamp 14 which emits ultraviolet rays UV; and a base 18 having formed therein an accommodation space 52 in which the auxiliary lamp 14 is accommodated between the base 18 and the outer side of the bottom portion 16a.

Abstract: A light emitting device comprises: an LED; a LED holder having a LED mount, a radiation fin provided on a back side or a periphery of the LED mount, and an engaging part projecting from a center of the back side of the LED mount; a power circuit supplying drive power to the LED; and a body having an inner space for accommodating the power circuit, one end, and the other end where the LED holder is fixed, wherein the other end of the body has an engaged part engaged to the engaging part of the LED holder, and holding the LED mount and the radiation fin in a state of separation from the body; heat conductivity of the LED mount and the radiation fin is higher than that of the engaged part of the body.

Abstract: [Object] To provide a light source device which allows the lighting starting properties of a high-pressure discharge lamp to be reliably improved without increasing the entire length of the light source device and exposing an auxiliary lamp to the outside. [Solution] A light source device 10 includes: a high-pressure discharge lamp 12; a bowl-shaped reflector 16 having an insertion hole 44 which is formed in a bottom portion 16a and in which a sealing portion 24 is inserted, an inner space 46, and a reflection surface 48 formed on an inner surface thereof; an auxiliary lamp 14 which emits ultraviolet rays UV; and a base 18 having formed therein an accommodation space 52 in which the auxiliary lamp 14 is accommodated between the base 18 and the outer side of the bottom portion 16a.

Abstract: A high pressure discharge lamp with auxiliary lamp comprises: a high pressure discharge lamp having an arc tube and at least one sealing portion, a pair of main electrodes, and a pair of feeders supplying power to the main electrodes; an auxiliary lamp having an airtight case, an inner electrode, and an outer electrode, wherein the inner electrode is arranged at a position so as to part the inner space to large and small spaces, the outer electrode is arranged at a position so as to face the large space, the auxiliary lamp as arranged as the large space faces the sealing portion.

Abstract: A light emitting device comprises: an LED; a LED holder having a LED mount, a radiation fin provided on a back side or a periphery of the LED mount, and an engaging part projecting from a center of the back side of the LED mount; a power circuit supplying drive power to the LED; and a body having an inner space for accommodating the power circuit, one end, and the other end where the LED holder is fixed, wherein the other end of the body has an engaged part engaged to the engaging part of the LED holder, and holding the LED mount and the radiation fin in a state of separation from the body; heat conductivity of the LED mount and the radiation fin is higher than that of the engaged part of the body.

Abstract: 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.

Abstract: A light emitting device comprises: a surface light source for a surface-emission; a CPC lens having a light receiving surface, a side reflective surface, and a light emitting surface, the light receiving surface receiving a part of light from the surface light source, the side reflective surface reflecting the light from the light receiving surface, and the light emitting surface facing the light receiving surface and emitting the light; and a reflector containing the surface light source and the CPC lens, and having a concaved reflective surface for reflecting forward the light deviating the light receiving surface from the surface light source, wherein a ratio of a illumination area of the surface light source to an area of the light receiving surface of the CPC lens is not less than 0.63 and not more than 2.93.

Abstract: A concave reflecting surface of a reflector for use in a light emitting device has micro reflector segments protruded therefrom in multiple stages and in multiple radial columns, the micro reflector segments each having a convex curved surface which is defined by a locus of a circular arc moved in parallel in a radial direction of the concave reflecting surface, and a radius of the convex curved surface, in each of the reflection regions, is set to be smaller when the convex curved surface is positioned closer to a point on which light emitted from each of the directional light sources and traveling on the light axis is incident, and is set to be larger when the convex curved surface is positioned more distant from the point.

Abstract: 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.

Abstract: 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.

Abstract: A starting circuit of a starting device for a high-pressure discharge lamp including an auxiliary light source has a diode placed in a forward direction in one of a pair of output lines which connect a main lighting circuit for generating AC voltage to the high-pressure discharge lamp and the auxiliary light source; a capacitor having one end connected to a cathode side of the diode; a boosting transformer including a primary winding, and a secondary winding having one end connected to an anode side of the diode or to the other output line and also having the other end connected to the other end of the capacitor; a high-frequency voltage generation circuit for continuously generating high-frequency voltage in combination with the primary winding; and a short-circuit switch for maintaining a short-circuit condition at both ends of the diode after the high-pressure discharge lamp is started.

Abstract: 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.

Abstract: A light emitting device 10A comprises: a bowl-shaped reflector 12 having a focal point F; and illuminators 14 have LED elements 28 being square in planar view and lenses 30 forming virtual images I of the LED elements 28 behind the LED element 28; wherein a position of each of the virtual images I from the lens 30 is farther than a position of the focal point F from the lens 30; when a distance A between the virtual image I and the focal point F and a length of outer circumference B of the LED element 28 being square in planar view are assumed, a value of A divide B (A/B) is not less than 0.08 and not more than 0.42.

Abstract: 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.

Abstract: The high-pressure discharge lamp includes: an arc tube; sealing portions which respectively have preseal glasses embedded therein, and at least one of which has an inert gas enclosing space which is arranged so as to be in contact with an outer surface of a corresponding the one preseal glass; a pair of feeders including a pair of electrodes, external lead rods, and metal foils, respectively; an external conductor which is arranged on an outer surface of the one sealing portion so as to be corresponded to the inert gas enclosed space, and connected to the external lead rod from the other sealing portion; and an internal conductor which is arranged in the inert gas enclosing space in the one sealing portion, and which has an electric potential identical to that of one feeder corresponding to the one sealing portion around which the external conductor is arranged.