Claims
- 1. A liquid crystal display system responsive to a video display signal having a frame rate comprising:
- a transparent coverplate having a first electrode structure comprising a multiplicity of electrically independent transparent conductive stripes formed as elements on one of its surfaces;
- a second electrode structure formed on a semiconductor wafer having a plurality of elements;
- a layer of liquid crystal material sandwiched between said first electrode structure and said second electrode structure;
- an insulating spacer providing electrical insulation and physical spacing between said first electrode structure and said second electrode structure;
- sealing means for providing retention of said liquid crystal material between said transparent cover plate and said semiconductor wafer;
- means for inversion of an applied video signal at a periodic rate equal to the frame rate of a video display signal, thus providing an inverted and a non-inverted video signal at alternate frames;
- means for maintaining the polarity of the inverted video signal the same as the polarity of the non-inverted video signal;
- means for the sequential application and removal of a constant value of potential to each of said multiplicity of electrically independent transparent conductive stripes at a periodic rate equal to the frame rate of said video display signal; and
- addressing means for applying said inverted and said non-inverted video signals, alternately received from the means for inversion, to said second electrode structure whereby the direction of current flow between elements of said first electrode structure and said second electrode structure is reversed at a periodic rate equal to the frame rate of the video display signal.
- 2. A liquid crystal display system according to claim 1 in which the elements of said second electrode structure comprises a matrix array of reflective electrodes.
- 3. A liquid crystal display system according to claim 1 in which said insulating spacer defines a plurality of elemental liquid crystal cells and said addressing means comprises a conventional metal oxide semiconductor field-effect transistor and a video storage capacitor.
- 4. A liquid crystal display system according to claim 1 in which said second electrode structure connects to a common bus.
- 5. A method of increasing the life of a liquid crystal material located between first and second structures in a liquid crystal display system for displaying successive frames of video signal information, comprising the steps of:
- maintaining polarity of the video signals applied to one of said electrode structures the same during successive frames and;
- reversing the direction of the current flow between the first and second electrode structures at the end of each frame.
- 6. A liquid crystal display system responsive to a video display signal having a frame rate comprising:
- a transparent coverplate having a first electrode structure comprising a multiplicity of electrically independent transparent conductive stripes formed on one of its surfaces;
- a second electrode structure formed on a semiconductor wafer;
- a layer of liquid crystal material sandwiched between said first electrode structure and said second electrode structure;
- an insulating spacer providing electrical insulation and physical spacing between said first electrode structure and said second electrode structure;
- a seal providing retention of said liquid crystal material between said transparent cover plate and said semiconductor wafer;
- means for inversion of an applied video signal at a periodic rate equal to the frame rate of a video display signal, thus providing an inverted and a non-inverted video signal at alternate frames wherein said inverted and said non-inverted video signals V.sub.(t) are derived from said video display signal, Video.sub.(t), according to the relation:
- -V.sub.(t) = [Video.sub.(t) (-1).sup.m ] + V.sub.max [1/2 - 1/2(-1).sup.m ]
- where m equals the number of the frame and V.sub.max is said constant value of potential applied to each of said multiplicity of electrically independent transparent conductive stripes;
- means for maintaining the polarity of the inverted video signal the same as the polarity of the non-inverted video signal;
- means for the sequential application and removal of a constant value of potential to each of said multiplicity of electrically independent transparent conductive stripes at a periodic rate equal to the frame rate of a video display signal; and
- addressing means for applying said inverted and said non-inverted video signals, alternately received from the means for inversion, to said second electrode structure whereby the direction of current flow between elements of said first electrode structure and said second electrode structure is reversed at a periodic rate equal to the frame rate of the video display signal.
Parent Case Info
This is a continuation of application Ser. No. 509,376 filed Sept. 24, 1974, now abandoned.
Non-Patent Literature Citations (1)
Entry |
lechner et al., "Liquid Crystal Displays", Proceedings of the IEEE, vol. 59, No. 11, Nov., 1971, pp. 1566-1579. |
Continuations (1)
|
Number |
Date |
Country |
Parent |
509376 |
Sep 1974 |
|