Patent ID: 8748935

Claim:
A light-emitting chip comprising: a plurality of light-emitting thyristors that are disposed on a substrate and each of which has a first anode terminal, a first cathode terminal, and a first gate terminal; a plurality of setting thyristors that are disposed on the substrate to correspond to the plurality of light-emitting thyristors, each of which has a second anode terminal, a second cathode terminal, and a second gate terminal, and each of which is switched to an ON state to set the absolute value of a threshold voltage of the corresponding light-emitting thyristor to be smaller than that in an OFF state; a plurality of transmission thyristors that are disposed on the substrate to correspond to the plurality of setting thyristors, each of which has a third anode terminal, a third cathode terminal, and a third gate terminal, and each of which is sequentially switched to an ON state to set the absolute value of a threshold voltage of the corresponding setting thyristor to be smaller than that in an OFF state; a plurality of first connecting resistors that are disposed on the substrate and that connect the first gate terminals of the plurality of light-emitting thyristors and the second gate terminals of the plurality of setting thyristors to each other such that the light-emitting thyristors and the setting thyristors correspond with each other; a plurality of second connecting resistors that are disposed on the substrate and that connect the second gate terminals of the plurality of setting thyristors and the third gate terminals of the plurality of transmission thyristors to each other such that the setting thyristors and the transmission thyristors correspond with each other; and a plurality of third connecting resistors that are disposed on the substrate and that connect the first gate terminals of the plurality of light-emitting thyristors to a power supply line supplied with a source potential for supplying drive power.