Patent ID: 8305415

Claim:
A light-emitting device comprising: a self-scanning light-emitting element array including: a plurality of light-emitting elements that are arrayed in line; a plurality of memory elements that are provided so as to correspond to the respective light-emitting elements, that are electrically connected to the respective light-emitting elements, that are each set at any one of an ON state and an OFF state, and that cause the respective light-emitting elements to be likely to be set at an ON state in a case of being set at the ON state in comparison with a case of being set at the OFF state; and a plurality of switch elements that are provided so as to correspond to the respective memory elements, that are electrically connected to the respective memory elements, that are each set at any one of an ON state and an OFF state, that are set so as to allow a sequential shift of the ON state from one end side to the other end side, and that causes the respective memory elements to be likely to be set at the ON state in a case of being set at the ON state in comparison with a case of the OFF state; and a light-up controller including: a transfer signal generating unit that supplies, to the plurality of switch elements, a transfer signal that sets the plurality of switch elements so as to allow the sequential shift of the ON state from the one end side to the other end side; a memory signal generating unit that supplies a memory signal to a plurality of the memory elements corresponding to a plurality of the light-emitting elements of a group among a plurality of groups into which the plurality of light-emitting elements are divided, the memory signal causing, in a case where a switch element corresponding to a light-emitting element forming the group is set at the ON state, a memory element corresponding to the switch element set at the ON state to be temporarily changed from the OFF state to the ON state if the light-emitting element corresponding to the switch element is intended to light up, and the memory element corresponding to the switch element set at the ON state to be kept in the OFF state if the light-emitting element corresponding to the switch element is not intended to light up, and then causing the memory element having been temporarily changed to the ON state to be temporarily set at the ON state again; and a light-up signal generating unit that supplies, to the plurality of light-emitting elements, for each group, a light-up signal that causes a light-emitting element intended to light up to be set at the ON state after causing a memory element corresponding to the light-emitting element intended to light up to be set at the ON state.