Patent ID: 9274265
Filing Date: 2016-03-01
CPC Classification: G02B

Claim Text:
1. A surface light source apparatus comprising: a point light source; and a light guide plate having a hole formed near one side surface thereof, said hole being formed at a position where said point light source is to be arranged, wherein said one side surface of said light guide plate has, in a portion thereof near said hole, a prism having a saw-toothed shape in a cross-section thereof parallel to a front surface of said light guide plate; a wall surface of the light guide plate that defines a side surface of the hole has a first protrusion protruding toward a center of the hole; the first protrusion is disposed at a portion of the side surface of the hole that is closest to the one side surface; said first protrusion is a convex lens having a focal point thereof positioned at a center of light emission of said point light source; and a conic constant K of a curved surface of said convex lens satisfies −1<K≦0.