LIGHT EMITTING ELEMENT ARRAY DRIVING CIRCUIT

摘要

PURPOSE:To provide a drive circuit correcting the irregularity of the quantity of light of a light emitting element. CONSTITUTION:Registers RG1-RGn and latch circuit LT1-LTn hold the density data signal from a printing data output part 10 in a pixel unit and counters CT1-CTn successively output a signal having the pulse width corresponding to the density data signal in synchronous relation to a strobe signal. A correction memory circuit 50 outputs the correction data corresponding to the irregularity of the quantities of light at every LEDs and registers HR1-HRn input the correction data to hold the same. Current setting circuit groups CS1-CSn supply the drive current corresponding to the correction data held to the registers HR1-HRn to LEDs only for the time corresponding to pulse width. As a result, even if the operation characteristics of the respective LEDs are different, no irregularity is caused in printing density at every gradation level.