AREA GRADATION PRINTING METHOD FOR END-FACE LIGHT EMITTING EL PRINTER

摘要

PURPOSE:To improve picture quality by forming one main scanning line in such a way that a line head performs line light emission several times and controlling the light emission frequency of an end-face light emitting type EL element corresponding to a picture element on one main scanning line according to density information shown by an input printing signal. CONSTITUTION:A timing controller 20 generates a printing signal instructing four line light emissions to form one main scanning line by temporarily storing and compressing printing input form an interface 18. Consequently, a line head 12 repeats line light emissions four times while one main scanning line is printed. A data processing circuit 25 discriminated the density of each picture element shown by the input printing signal and turns the printing signal into a signal corresponding to each density. Signals corresponding to respective densities are sequentially transmitted to a driver 21 via shift registers 231 to 234 and latches 241 to 244. The driver 23 and a common driver 22 are synchronized by the control of the controller 20 to operate the line head 12.