Patent ID: 6268878
Filing Date: 2001-07-31
Classification: G06K

Abstract:
An optical writing head driving device comprising:an optical head in which a plurality of light emittng arrays are arranged in a line in a main scanning direction, each said light emitting array comprising a cathode terminal, an anode terminal, and a predetermined number of light emitting elements that each emit light onto a photosensitive member in accordance with image data;first storage means for storing adjustment data which is obtained based on a quantity of light emission from each said light emitting element measured while said optical writing head is controlled to emit light, said adjustment data being prepared for adjusting the quantity of light emission from each said light emitting element;second storage means, having a higher data transfer rate than a data transfer rate of said first storage means, for also storing the adjustment data;adjustment data transferring means for transferring the adjustment data from said first storage means to said second storage means in response to a predetermined initial operation performed substantially before a printing process begins;read means for reading out the adjustment data from said second storage means;adjustment means for adjusting drive signals, which correspond to the image data and which are prepared for driving said light emitting elements, in accordance with the adjustment data read out by said read means;element select/drive means for sequentially selecting said light emitting elements of each said light emitting array, and for driving said selected light emitting elements unit by unit;drive signal supply means for supplying said adjusted drive signals to said selected light emitting elements; andstrobe signal generation means for generating a strobe signal which determines drive timings to be assigned to each of the light emitting arrays during each writing cycle for one line, and for supplying the generated strobe signal to said element select/drive means and said drive signal supply means;wherein said element select/drive means sequentially applies a selection signal to the cathode terminal on a target light emitting array each time said element select/drive means receives the strobe signal to select the target light emitting array;wherein said read means reads out the adjustment data from said second storage means lust before said element select/drive means applies the selection signal to the target light emitting array;wherein said adjustment means adjusts an amperage of the drive signals for the light emitting elements determined by the image data in accordance with the adjustment data read-out by said read means; andwherein said drive signal supply means supplies the drive signals whose amperage has been adjusted by said adjustment means to the anode terminal on the array to which the selection signal is applied by said element select/drive means, each time said drive signal supply means receives the strobe signal.