Light-emitting element driving apparatus

A light-emitting element driving apparatus driving a plurality of light-emitting elements of mutually different luminescent colors, comprising a driving apparatus provided for each light-emitting element, the driving apparatus comprising:

• a constant-current circuit including a plurality of constant-current sources that are connected in parallel with each other and are respectively connected in series to a light-emitting element to supply current to the light-emitting element, wherein the plurality of constant-current sources arrange 1st to Nth (N is an integer not smaller than 2) constant-current blocks each including 1st to Mth (M is an integer not smaller than 2) constant-current sources, and a current ratio among the 1st to Mth constant-current sources is substantially identical in all of the constant-current blocks;
• and
• a control circuit selectively bringing the 1st to Mth constant-current sources into a valid state based on light-quantity correction data representing valid/invalid states of the 1st to Mth constant-current sources commonly for all of the constant-current blocks, and selectively turning on the 1st to Nth constant-current blocks based on gradation data representing on/off states of the 1st to Nth constant-current blocks,
• wherein a constant-current source belonging to a turned on constant-current block and being in a valid state supplies current to the light-emitting element.