GRADATION DISPLAY DEVICE, IMAGE READING DEVICE AND IMAGE FORMING DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a gradation display device capable of successively switching and using many kinds of pattern groups without specially increasing the required capacity of the memory for holding the pattern groups and increasing the number of display gradations without specially increasing the number of frames in which the pattern number in a basic pattern group and the successive switching of the pattern groups make one round.

SOLUTION: The gradation display device is provided with: a gradation memory Prg which stores a basic pattern group GPTNA that is made of pattern groups expressing the gradation by the distribution of the on/off signals of each pixel of a pixel block; a means 69b which changes an angular signal Xbs for every switching of the display blocks; a means which reads a pattern Dbp corresponding to gradation data from the gradation memory; a rotating means which converts the pattern into patterns Dbs that are rotated for angles 0/90/180/270°corresponding to the angular signal Xbs; and a means which outputs the on/off signals of the rotated patterns Dbs to a two dimensional display means. The basic pattern group is a light emitting pattern group which expresses each gradation of a narrow gradation range that is one half of the wide gradation range expressed by the gradation data and each gradation is expressed by the combination of a plurality of basic patterns.

COPYRIGHT: (C)2006,JPO&NCIPI