Patent ID: 7534027

Claim:
A planar light source comprising: a light source part; a light guide part for guiding light emitted from said light source part to form planar emission of said light; and a reflector with a rear side portion and two side portions surrounding the light source except at a face where light from the light source directly enters the light guide part, and said reflector for reflecting light emitted from said light source part to allow said light to enter said light guide part, said reflector including a member at the rear side portion capable of controlling the amount of reflected light from the reflector, and the member is configured to control an amount of reflected light from at least two surfaces, wherein said member for controlling the amount of reflected light comprises: slits formed at least on one surface of said reflector; and a reflective plate arranged on the rear surface of said reflector, said reflective plate having light absorbers capable of overlapping said slits, and wherein said reflective plate is moved to control the amount of reflected light.