| 摘要 |
PROBLEM TO BE SOLVED: To perform the multi-gradation display which is stabilized in a display quality by a simple matrix-type LCD, by controlling a number of times of display on and display off to each dot of a liquid crsytal display panel. SOLUTION: The X electrode driving circuits 402-1-402-8 apply the voltage corresponding to the display data during a horizontal scanning period of each dot of 1-480 lines of a liquid crystal display panel 401. A number of frames for completing the half tone data is 4 in a gradation control block of the X electrode driving circuit 402, and a ratio of the display on and display off of each dot is controlled to be 0:3, 1:2, 2:1, 3:0 on the basis of the modulation of the pulse width obtained by equally dividing one hozirontal scanning period into three parts. As the result of the same, the gradation number becomes 5×4+1=13, and the 13 gradation display of 0/12-12/12 can be realized.
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