Abstract: A light control member formed by a prism sheet 5 is arranged along an emitting surface 12 of a light guide plate of a side light type surface light source device for liquid-crystal display backlighting arrangement and the like. The prism sheet 5 is provided with numerous projections formed with a height H1 at a pitch D1. Roughness is imparted to the emitting surface 12 by matt-processing or adhesion of fine particles. The roughness is preferably within the arithmetic average roughness Ra range 0.02-0.25 &mgr;m. Non-uniformity may be applied to height H1 of the prism sheet 5. The tendency of the prism sheet to adhere to the emitting surface is reduced and degradation of light quality prevented by the roughness of the emitting surface and/or non-uniform height of projections on the prism sheet.

Abstract: A light control member formed by a prism sheet 5 is arranged along an emitting surface 12 of a light guide plate of a side light type surface light source device for liquid-crystal display backlighting arrangement and the like. The prism sheet 5 is provided with numerous projections formed with a height H1 at a pitch W1 D1. Roughness is imparted to the emitting surface 12 by matt-processing or adhesion of fine particles. The roughness is preferably within the arithmetic average roughness Ra range 0.02-0.25 &mgr;m. Non-uniformity may be applied to height H1 of the prism sheet 5. The tendency of the prism sheet to adhere to the emitting surface is reduced and degradation of light quality prevented by the roughness of the emitting surface and/or non-uniform height of projections on the prism sheet.

Abstract: A thin illumination device providing uniform luminance distribution on the diffusing plate comprising a reflecting plate, linear light sources arranged in the vicinity of the reflecting plate and a diffusing plate arranged on the opposite side of the reflecting plate with regard to the light sources, section of the reflecting plate having a shape of continuous curves having different curvature.

Abstract: A surface illuminant device which is usable as a backlight for liquid crystal display units and does not allow a light diffusing sheet 2 or a reflecting sheet 4 to be slackened due to variations of temperature and humidity. Collars 6a and 6b of a holder 6 are disposed on surfaces of a light transmitter 1 opposed to each other so that a gap slightly larger than thickness of the light diffusing sheet 2 is formed between the collar 6a of the holder 6 and a surface of emergence 1a of the light transmitter 1, and a gap slightly larger than thickness of the reflecting sheet is formed between the surface 1b opposed to the surface of emergence 1a of the light transmitter 1 for allowing ends of the light diffusing sheet and the reflecting sheet to be freely movable within a predetermined range in the gaps, whereas the other ends of the light diffusing sheet and the reflecting sheet are fixed to the light transmitter 1 by fixing means 3, 5, 10 and 14.

Abstract: A thin illumination device providing uniform luminance distribution on the diffusing plate comprising a reflecting plate, linear light sources arranged in the vicinity of the reflecting plate and a diffusing plate arranged on the opposite side of the reflecting plate with regard to the light sources, section of the reflecting plate having a shape of continuous curves having different curvature.

Abstract: A thin illumination device providing uniform luminance distribution on the diffusing plate comprising a reflecting plate, linear light sources arranged in the vicinity of the reflecting plate and a diffusing plate arranged on the opposite side of the reflecting plate with regard to the light sources, section of the reflecting plate having a shape of continuous curves having different curvature.

Abstract: An illumination device having a reflecting plate, at least one linear light source arranged on a first side of the reflecting plate, a diffusing plate arranged on a second side of the reflecting plate, and a light quantity adjusting member formed integrally with the reflecting plate.

Abstract: An illumination device comprising a reflecting plate, a single or a plural number of linear light source(s) arranged over said reflecting plate and a diffusing plate arranged over said light source(s), a light quantity adjusting means being arranged on the surface of the linear light source on between said light source(s) and said diffusing plate, and said illumination device being so adapted as to uniformalize luminance distribution on the diffusing plate by selecting shape and size of light-transmitting portions of the light quantity adjusting means.

Abstract: An illumination device comprising a reflecting plate, a single or a plural number of linear light source(s) arranged over said reflecting plate and a diffusing plate arranged over said light source(s), a light quantity adjusting means being arranged on the surface of the linear light source on between said light source(s) and said diffusing plate, and said illumination device being so adapted as to uniformalize luminance distribution on the diffusing plate by selecting shape and size of light-transmitting portions of the light quantity adjusting means.

Abstract: An illumination device comprising a reflecting plate, a single or a plural number of linear light source(s) arranged over said reflecting plate and a diffusing plate arranged over said light source(s), a light quantity adjusting means being arranged on the surface of the linear light source on between said light source(s) and said diffusing plate, and said illumination device being so adapted as to uniformalize luminance distribution on the diffusing plate by selecting shape and size of light-transmitting portions of the light quantity adjusting means.