Patent ID: 6152570
Filing Date: 2000-11-28
Classification: G02B,Y10S

Abstract:
A surface light source device comprising:a light diffusion plate made of a light scattering conductor, the light diffusion plate having a light emission surface and a back surface, the light emission surface facing an object to be illuminated;a light conducting element positioned on a far-side of the object to be illuminated and formed of a transparent material, the light conducting element having a light incident surface, an emission surface and a back surface, the emission surface of the light conducting element being close to the back surface of the light diffusion plate;a reflector sheet positioned to face the back surface of the light conducting element; anda rod shaped light source arranged along the light incident surface of the light conducting element,the light conducting element having a reducing thickness with increasing distance from the light incident surface of the light conducting element, andthe light diffusion plate having an increasing thickness with increasing distance from the light incident surface of the light conducting element; andan incident angle correction member for correcting a propagation direction of a light incident on the light diffusion plate, the incident angle correction member being inserted between the light conducting element and the light diffusion plate.