초록 ▼

A light regulation element regulates both the travelling direction and diffusion state of a light emitted from a surface light source device. Lights from a cylindrical light source 2 such as a cold cathode tube is introduced in a light guide 1. The light guide 1 has an emission surface 1a on the sid

A light regulation element regulates both the travelling direction and diffusion state of a light emitted from a surface light source device. Lights from a cylindrical light source 2 such as a cold cathode tube is introduced in a light guide 1. The light guide 1 has an emission surface 1a on the side opposite to a reflection element 4, and a light regulation element 3 is arranged in opposition to the emission surface 1a. Protrusions 3a are formed on one surface or both surfaces of the light regulation element 3. Coated on the surface on the light emission side of the light regulation element 3 is a light diffusion layer 5. The turbidity of the light diffusion layer 5 falls within a range from 1900 cm.sup.-1 to 2400 cm.sup.-1 . The light emitted from the emission surface 1a of the light guide penetrates the light regulation element 3, thereby causing the light travelling direction to be regulated. Then, the light whose travelling direction has been regulated penetrates the light diffusion layer 5, thereby causing a light diffusion. The light diffusion layer 5 is formed, for example, by mixing fine particles of a glass having a light penetrability or of a synthetic resin such as acryl and silicone, or fine hollow particles of glass, acryl resin or the like, or air bubbles in a coating material having a light penetrability.

대표청구항 ▼

[ What is claimed is:] [1.]1. A light regulation device, comprising:a light regulation element having a plurality of protrusions to bend, through refraction, a direction of light penetrating said light regulation element from a light receiving side to a light emitting side, opposite of the light rec

[ What is claimed is:] [1.]1. A light regulation device, comprising:a light regulation element having a plurality of protrusions to bend, through refraction, a direction of light penetrating said light regulation element from a light receiving side to a light emitting side, opposite of the light receiving side; anda light diffusion layer formed directly on said light regulation element without an air gap between the light diffusion layer and the light regulation element, whereinsaid protrusions extend in a first direction on said light receiving side and in a second direction on said light emitting side, said first direction being substantially perpendicular to said second direction so as to perform both lateral light bending and longitudinal light bending.