Patent ID: 8672528

Claim:
A planar illumination device comprising: a plurality of light sources; a light guide plate for allowing light emitted from the light sources to exit in a planar manner; a plurality of optical sheets disposed on a light-emitting surface side of the light guide plate; and a reflection sheet disposed on an opposite side to the light-emitting surface side of the light guide plate with reference to a position of the light guide plate, wherein the planar illumination device has a chassis for fixing the plurality of optical sheets, at least one of the plurality of optical sheets has a light-shielding portion provided in a part of a region corresponding to a non-light-emitting region of the planar illumination device, one of the plurality of optical sheets that is disposed in a position farthest from the light guide plate is a reflection type polarizer that allows some light to be transmitted therethrough and allows other light to be reflected thereby, and a length of the reflection type polarizer is longer in a first direction than a length of the light guide plate such that an edge of the reflection type polarizer is located closer to a side of the light sources than is an edge of the light guide plate, the first direction being a direction perpendicular to a plane on which the light sources are provided out of planes forming the chassis.