| 摘要 |
PURPOSE:To enable any person to easily and surely adjust the contrast of the screen of a dot map type LCD display device without individual variation. CONSTITUTION:An ordinary mode and a screen contrast adjusting mode are selected by a microcomputer, and when the screen contrast adjusting mode is selected, a test pattern having plural steps of variable density is displayed on the LCD display device by a control LSI 7 for on/off controlling dots. While viewing the display, a VR 10 is adjusted and the voltage of a bias voltage generator 9 impressed on the LCD display device 8 is adjusted. When such adjustment is completed, the pattern is switched to an ordinary pattern. |
