Patent ID: 7223010

Claim:
A light guide panel of an edge-light type backlight system comprising: a light incident part into which light enters from a point light source; and a light emitting surface from which light is emitted, wherein the light incident part comprises: a light incident surface on which a prism pattern is formed, the light incident surface facing the point light source; and first and second surfaces extending from the light incident surface in a direction in which light travels and adapted to reflect light passing through the light incident surface to reduce a direction angle, the first and second surfaces being opposite to each other with respect to an optical axis, wherein the prism pattern has a horizontal section in the shape of triangles, and wherein a relationship between an apex angle of the prism pattern and a half-maximum angle satisfies the following formula: C 3 ≧(90−α)×2, where C 3 denotes the apex angle of the prism pattern, and α denotes the half-maximum angle at which intensity of light emitted by the point light source is half maximum.