Control method and apparatus for optical printer head

A control apparatus for controlling an optical printer having a movable photosensitive member and a plurality of dot type light emitting elements linearly aligned normal to the moving direction of the photosensitive member, the control apparatus energizing each said light emitting element for light emission based on one line amount of received image data, said control apparatus comprising:

• a shift register for receiving image data;
• a latch register for receiving the image data from said shift register;
• strobe signal output means for selecting one from a plurality of strobe signals each having a different ON time in accordance with image density information, said strobe signals including a predetermined number of base signals each having a different ON time and a plurality of composite signals each composed of a different combination of the base signals,
• said latch register receiving one line amount of image data by a number of times equal to said predetermined number of base signals, and
• logic means for controlling power supply to the light emitting elements, said logic means receiving signals from said latch register and said strobe signal output means and energizing the light emitting elements corresponding to the image data for light emission for a time corresponding to the ON time of the selected strobe signal.