mi 3,975,726 [45| Aug. 17, 1976
METHOD AND DEVICE FOR DRIVING IN TIME DIVISION FASHION FIELD EFFECT MODE LIQUID CRYSTAL DISPLAY DEVICE FOR NUMERIC DISPLAY
Inventor: Hideaki Kawakami, Hitachi, Japan
Assignee: Hitachi, Ltd., Japan
Filed: May 20, 1974
Appl. No.: 471,602
Foreign Application Priority Data
May 23. 1973 Japan 56805/73
U.S. CI 340/336; 340/324 R;
350/160 LC
Int. CI.2 G08B 5/36
Field of Search 340/336, 378 R;
350/160 LC, 148, 158; 313/510, 513, 520;
358/59, 61
In a method and device for driving in time division fashion a field effect mode liquid crystal display device for numeric display, having a plurality of sets of segment electrodes, each set being provided for one digit, and a plurality of separated digit electrodes disposed opposite to the plurality of segment electrode sets respectively, the corresponding segment electrodes of the respective digits being commonly connected, the amplitude of voltages applied to the display points in the half-selected and non-selected states are kept constant while the effective value of the voltage applied to the display points in the selected state is arbitrarily set by changing the duty ratio of selection time so that color in the display may be changed.
8 Claims, 14 Drawing Figures
