IMAGE FORMING DEVICE

摘要

PURPOSE: To maintain resolution and gradation properties and to increase difference in density of black and white of print by outputting line data based on additional data by LED array on at least one subline. CONSTITUTION: As to the stored line data of the N-th line and the stored line data of the (N+1)-th line, a comparator 27 compares the presence or absence of exposure of an LED for the front and the rear dots in the vertical scanning direction. The compared N-th line data are outputted to an image formation part 13 by LED array 9 and thereafter additional data are outputted from a third memory 28 by LED array 9 and the (N+1)-th line data are transferred to a second memory 26. Furthermore, the (N+2)-th line data are stored in a first memory 25 and the (N+2)-th line data are compared with the (N+1)-th line data and the following additional data are formed. This processing is successively repeated and the respective line data are compared mutually by the comparator 27 and the additional data are formed.