PURPOSE: To improve the expressing capability of half tones by providing plural patterns different from one another which can express the same intermediate level and using these patterns in order or at random.
CONSTITUTION: A pattern number determining circuit 5 supplies information, which indicates a pattern to be used out of plural patterns in a selected group in a pattern memory 6, to the pattern memory 6 by an address signal and increments repeatedly the address signal a number of times corresponding to the number of patterns. Output data of the pattern memory 6 is transmitted from a multiplexer 9 to a multiplexer 13 and is transmitted to a driving part 14. Plural patterns having equal density gradations are repeated while being changed with respect to equal density areas and areas where density gradation levels are less changed, thereby improving half tone expression.
KIKUCHI YOSHIKI
MIYAZAKI KOUICHI
Next Patent: COLOR PICTURE INPUT AND RECORDING METHOD