PURPOSE: To make high transmissivity with high diffusibility of light compatible in a display light, etc.
CONSTITUTION: A hologram diffusion sheet 22 is provided in a composite plate 20 provided in front of the unit display light 10a. The hologram diffusion sheet 22 is a diffusion element using a diffraction phenomenon of light, and is provided with the high diffusibility and the high transmissivity of light. Since the light from a light source 12 is diffused in the multi-direction without substantially being attenuated, the necessity that diffusion processing such as milky-white, etc., is performed on a sign plate 23 is eliminated, and a display with the high luminance and the high diffusibility is obtained. By properly setting a diffusion angle, the display light is diffused to only a required range in concentrative. Further, by using an LED generating the light of a prescribed color, a color plate is omitted.
MATSUMOTO YOSHIHIRO
NISHIKI TOMONORI
MAMIYA MASARU
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