Patent ID: 8736542

Claim:
A backlight using a plurality of light-emitting diodes as a light source and illuminating a liquid crystal display panel from a back thereof, the light-emitting diodes being formed of units, the units each being a minimum unit of m×n where m and n are natural numbers, the backlight comprising: a driving part configured to drive the light-emitting diodes on a unit-by-unit basis; a block setting part configured to group two or more of the units into a block; a luminance controlling part configured to control a luminance of the light-emitting diodes of the block independently on a block-by-block basis; and a sequential circuit connected to the units and configured to output a signal that sequentially selects lines of the light-emitting diodes with respect to each of the units, wherein the block setting part is configured to change a number of the units grouped into the block by controlling an operation of a first switch connected between the units and to control an operation of a second switch connected between an output terminal connected to a first one of the units and an input terminal connected to a second one of the units in the sequential circuit in changing the number of the units grouped into the block.