Patent ID: 7802911

Claim:
A backlight apparatus of a sidelight type comprising: a light guide plate having an incident face on a lateral face; and a light source unit having a plurality of substrates; wherein each of the plurality of substrates is respectively disposed on the incident face side of the light guide plate such that a face of each of the plurality of substrates is parallel with a main face of the light guide plate; the plurality of substrates are arranged adjacent to one another in a thickness direction of the light guide plate; a plurality of light emitting devices are mounted in columns on each of the substrate faces of the plurality of substrates such that light emitted from the plurality of light emitting devices is directed to the incident face; a heat sink plate is disposed between adjacent ones of the plurality of light emitting devices; and switching on of the plurality of light emitting devices on each of the plurality of substrates is controlled independently of any other of the plurality of substrates.