Abstract: In order to make the brightness approximately uniform over a diffusion board, a back-light device is provided with a light transmission controlling film having a planar form in a shape of a projection of the lamp on the diffusion board. The film is disposed in parallel to the lamp axis between the lamp and the diffusion board.

Abstract: Disclosed is a fluorescent lamp arrangement for uniformly illuminating a display panel wherein a fluorescent lamp having a glass tube is provided with electrodes at opposite sides thereof, a fluorescent layer is formed over an inner surface of the glass tube, and mercury and a rare gas are sealed in the glass tube; and a light-shading patterned layer is formed along a surface of the glass tube so as to make luminance on a display panel substantially uniform when the fluorescent lamp and the display panel are parallelly disposed to a plane which includes a longitudinal axis of the glass tube.

Abstract: A back light device for uniformly illuminating a liquid crystal display plate comprises a fluorescent lamp having a luminous tube formed by being turned up through a coupling in the same plane, a liquid crystal display plate to be illuminated by the light radiated from the fluorescent lamp, a diffused plate interposed between the liquid crystal display plate and the fluorescent lamp in parallel to the plane, and a reflector for reflecting the light radiated from the fluorescent lamp toward the diffused plate.