公开(公告)号：EP0425210A2

公开(公告)日：1991-05-02

申请号：EP90311528.5

申请日：1990-10-19

申请人： EEV LIMITED

发明人： Eaton, Timothy John ,  Pittock, Roger John

IPC分类号： G09G3/36

CPC分类号： G09G3/36 ,  G09G2320/029 ,  G09G2320/041 ,  G09G2320/043 ,  G09G2360/145

摘要： The contrast or absolute brightness of a multiplexed LCD is maintained at its preselected value using a feedback arrangement which includes an LCD element functioning as a reference element. The reference element is not used to display information but is continually driven ON and OFF. The average transmissivity of the ON and OFF states is determined and compared with a reference value, the result of the comparison being used to control the voltage levels of the drive waveforms applied to the LCD. By selecting appropriate ratios between the ON and OFF times of the reference element, the LCD can be operated to give optimum contrast, or may have its absolute brightness varied. Control may be effected remotely by reprogramming the microprocessor which determines the timing of the drive waveforms.

摘要翻译： 使用包括用作参考元件的LCD元件的反馈装置将多路复用LCD的对比度或绝对亮度保持在其预选值。 参考元素不用于显示信息，但不断驱动ON和OFF。 确定ON和OFF状态的平均透射率，并将其与参考值进行比较，比较结果用于控制施加到LCD的驱动波形的电压电平。 通过选择参考元件的ON和OFF时间之间的适当比例，可以操作LCD以提供最佳对比度，或者可以具有绝对亮度变化。 可以通过重新编程微处理器来远程实现控制，微处理器确定驱动波形的定时。

公开(公告)号：EP0425210B1

公开(公告)日：1995-08-23

申请号：EP90311528.5

申请日：1990-10-19

申请人： EEV LIMITED

发明人： Eaton, Timothy John ,  Pittock, Roger John

IPC分类号： G09G3/36

CPC分类号： G09G3/36 ,  G09G2320/029 ,  G09G2320/041 ,  G09G2320/043 ,  G09G2360/145

公开(公告)号：EP0425210A3

公开(公告)日：1992-08-19

申请号：EP90311528.5

申请日：1990-10-19

申请人： EEV LIMITED

发明人： Eaton, Timothy John ,  Pittock, Roger John

IPC分类号： G09G3/36

CPC分类号： G09G3/36 ,  G09G2320/029 ,  G09G2320/041 ,  G09G2320/043 ,  G09G2360/145

摘要： The contrast or absolute brightness of a multiplexed LCD is maintained at its preselected value using a feedback arrangement which includes an LCD element functioning as a reference element. The reference element is not used to display information but is continually driven ON and OFF. The average transmissivity of the ON and OFF states is determined and compared with a reference value, the result of the comparison being used to control the voltage levels of the drive waveforms applied to the LCD. By selecting appropriate ratios between the ON and OFF times of the reference element, the LCD can be operated to give optimum contrast, or may have its absolute brightness varied. Control may be effected remotely by reprogramming the microprocessor which determines the timing of the drive waveforms.