Optical writing head driving device and method of driving optical writing head

Abstract

A head controller,reads out adjustment data from a ROM,immediately after a power-on operation. The adjustment data is prepared for adjusting unevenness of light emission from LEDs in a LED head,. A buffer memory,stores the read adjustment data. The head controller,reads the adjustment data from the buffer memory,with high data transfer rate, and obtains bitmap data from a frame memory or the like (not shown). The head controller,sends the read bitmap data and the adjustment data to an anode driver,. The head controller,sends a strobe signal to the anode driver,and a cathode driver,. The anode driver,adjusts ampere of supplied currents (i.e. drive signals corresponding to the bitmap data) from the head controller,, in accordance with the received adjustment data in response to the reception of the strobe signal. The adjusted drive signals are sent to LED array chips,. At the same time, the cathode driver,selects one of the LED array chips,in accordance with the received strobe signal so that the LEDs emit even lights. The optical writing head driving device,performs the above operations repeatedly to sequentially emit lights from the LEDs chip by chip under time sharing control for 1 line writing. As a result, the bitmap data is written onto a photosensitive member evenly at a high speed.