Abstract: Disclosed herein is a back light device for LCDs. The back light device includes an inverter to supply an alternating current or a pulse, a plurality of fluorescent lamps to radiate visible light, a reflection member to reflect the light radiated from the fluorescent lamps, a diffusion member to diffuse the light, and a frame to house the above elements therein. An external electrode is provided at a first end of each of the fluorescent lamps, and an internal electrode is provided at a second end of each of the fluorescent lamps. An extension electrode is provided on an outer surface of the second end of each of the fluorescent lamps to be connected to an associated internal electrode. A holding terminal is provided at each of both ends of each fluorescent lamp to connect the external and extension electrodes to each other. Further, an inverter is provided to operate the fluorescent lamps.

Abstract: A backlight for a liquid crystal display includes a substantially planar waveguide and a plurality of light-emitting diodes positioned adjacent the waveguide. The plurality of light-emitting diodes emits light having a first wavelength range. A reactive element is disposed adjacent the waveguide. The reactive element emits light having a second wavelength range toward the waveguide when the reactive element is excited by light from the plurality of light-emitting diodes.

Abstract: A light source device for preventing a light guide plate from being discolored due to a light supplied by a lamp is disclosed. At least one masking film that is made of a transition metal oxide is disposed in a pathway of the light that is emitted by the lamp and transmitted to a display unit to display images in order to cut off ultraviolet rays having particular wavelengths capable of discoloring the light guide plate. Accordingly, it is possible to prevent the light guide plate, which is made of polyolefin resin composition to make it lightweight, from discoloring in yellow.

Abstract: A backlight device has a light guide plate, a rotary member, a rotary drive mechanism for rotating the rotary member, a plurality of mercury-free fluorescent lamps, and a power feed control mechanism. Each of the mercury-free fluorescent lamps has an arc tube mounted on the rotary member so as to extend parallel to the rotary shaft, a mercury-free discharge medium consisting of a rare gas sealed within the arc tube, and first and second electrodes for exciting the discharge medium. The mercury-free fluorescent lamps respectively emit lights of different colors. The emitted light enters the light guide plate through its light incident face and emerges from its light emission face.