Abstract: A substrate is formed in a rectangular shape, a plurality of light emitting elements are arranged on one end face of the substrate, and a translucent sealing material is adhered to the one end face to seal the light emitting elements. A light irradiation device is thin, which transfers heat generated at the light emitting elements to the substrate where the heat is dissipated. Even if the substrate is made thinner, the heat dissipation performance of the substrate can be maintained or enhanced when the dimension of the substrate is increased in the direction intersecting the one end face of the substrate.

Abstract: A substrate is formed in a rectangular shape, a plurality of light emitting elements are arranged on one end face of the substrate, and a translucent sealing material is adhered to the one end face to seal the light emitting elements. A light irradiation device is thin, which transfers heat generated at the light emitting elements to the substrate where the heat is dissipated. Even if the substrate is made thinner, the heat dissipation performance of the substrate can be maintained or enhanced when the dimension of the substrate is increased in the direction intersecting the one end face of the substrate.

Abstract: The present invention relates to an inorganic composition mainly containing a compound semiconductor, wherein the inorganic composition contains iridium element. The invention also relates to a method of producing an inorganic composite for producing an luminescent material, wherein the method comprises subjecting an inorganic composition mainly containing a compound semiconductor to an explosion by gunpowder and/or explosive in a sealed vessel. An inorganic composite for producing a luminescent material can be prepared by subjecting an inorganic composition to a doping treatment such as explosive treatment or heat-treatment. The inorganic composite can further be heat-treated to produce a luminescent material. The resulting luminescent material can be formed into a layer as a light emitter layer of an inorganic EL device.

Abstract: An inorganic EL element with a high luminance and an improved life can be produced by using a luminescent material which can be produced by an explosion method.

Abstract: The present invention is characterized by a DC-driven inorganic EL element useful for mobile and other applications, the EL element including at least plural electrode layers, and a light emitter layer made of an inorganic composition, which is provided between the electrode layers, wherein the attainted brightness in the DC drive is 10000 cd/m2 or more.

Abstract: A surface illuminating apparatus, which is provided with a transparent light guide plate 2, a reflecting plate 4 layered onto the rear surface of the light guide plate 2, and a light diffusion plate 6 layered onto the outer surface of plate 2. The light guide plate 2 and the reflecting plate 4 have an irregularly reflecting plate 3 therebetween. Light sources 8 are disposed at both lateral ends of the light guide plate 2, and formed on the outer surface of plate 2 is a light diffusion plate 6 having a plurality of spotted projections 7 regularly disposed and having a light condensing and diffusing function.

Abstract: A surface illuminating apparatus in which a plurality of transparent plates of different spot patterns formed of a large number of fine spots painted or printed at one side are layered in the relation that spotted surfaces having the painted or printed spots are not opposite to each other, thereby forming a surface illuminating body, a reflecting plate is brought into close contact with the spotted surface of the rearmost transparent plate, in turn, the rear surface of the body, a light diffusion plate in close contact with a non-spotted surface of the foremost transparent plate, in turn, the surface of the body, and light sources for irradiating light on the body are disposed at both lateral end sides of the body.