Patent ID: 8400583

Claim:
A light source apparatus, comprising: a light guide plate; a plurality of optical sheets provided so as to be layered on a light emitting surface of the light guide plate; and a frame housing the light guide plate and the plurality of optical sheets therein, wherein: one of the plurality of optical sheets which is arranged at a position most distant from the light guide plate is a prism sheet, the prism sheet having: (i) a plurality of prisms formed on one surface thereof which are extended in parallel with each other, and (ii) one or more projecting pieces which are integrally formed with the prism sheet in a shape projecting from a fringe of the prism sheet, the one or more projecting pieces engage to the frame, at least one of the one or more projecting pieces is a dark part suppressing projecting piece, sides making a pair of sides adjoining the dark part suppressing projecting piece are dark part suppressing sides, a first angle formed by a pair of dark part suppressing sides is equal to or smaller than a dark part suppressing angle, and second angles, making a pair of angles formed with a straight line and each of sides making the pair of dark part suppressing sides, are equal to or smaller than half of the dark part suppressing angle, the straight line: (i) passing through a region formed between the pair of dark part suppressing sides, (ii) passing through an intersection point of the pair of dark part suppressing sides, and (iii) being parallel or perpendicular to ridge lines of the prisms.