Optical print head having first and second power lines and image forming apparatus

摘要

Optical print head includes: light-emitting elements connected one-to-one to current supply lines branching from first power line at different positions in longitudinal direction; holding elements; signal writing unit writing luminance signal into each holding element, the luminance signal being represented by voltage indicating light emission amount of corresponding light-emitting element; second power line supplying reference voltage to each holding element, the reference voltage being reference when signal writing unit writes luminance signal into holding element; and driving drivers corresponding one-to-one with current supply lines and controlling current supplied to corresponding current supply line from first power line, in accordance with voltage held in corresponding holding element when signal writing unit has written luminance signal into corresponding holding element, wherein power source supplying the reference voltage to second power line is common with power source supplying voltage to signal output subunit outputting luminance signal.

主权项

1. An optical print head comprising:
a plurality of light-emitting elements that are connected to a plurality of current supply lines in one-to-one correspondence, the current supply lines branching from a first power line at different branch positions in a longitudinal direction thereof; a plurality of holding elements that are provided in one-to-one correspondence with the light-emitting elements; a signal writing unit that writes a luminance signal into each of the holding elements, the luminance signal being represented by a voltage indicating a light emission amount of a corresponding one of the light-emitting elements; a second power line that is different from the first power line, and supplies a reference voltage to each of the holding elements, the reference voltage being a reference when the signal writing unit writes the luminance signal into the holding element; and a plurality of driving drivers that are provided in one-to-one correspondence with the current supply lines, and each control a current supplied to a corresponding one of the current supply lines from the first power line, in accordance with a voltage that is held in a corresponding one of the holding elements when the signal writing unit has written the luminance signal into the corresponding one of the holding elements, wherein the signal writing unit includes a signal output subunit that outputs the luminance signal, and a power source that supplies the reference voltage to the second power line is common with a power source that supplies a voltage to the signal output subunit.