Liquid crystal apparatus with gradation information signals and DC bias
AssigneeCanon Kabushiki Kaisha
InventorsShuzo Kaneko, Ryoji Fujiwara, Akio Yoshida, Tomoro Maruyama
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AssigneeCanon Kabushiki Kaisha
InventorsShuzo Kaneko, Ryoji Fujiwara, Akio Yoshida, Tomoro Maruyama
Estimating the term…
Disclosed is a liquid crystal apparatus including a liquid crystal panel having a pair of electrodes and a liquid crystal exhibiting spontaneous polarization and arranged between the pair of electrodes, first means for applying a gradation voltage signal corresponding to gradation information to the pair of electrodes, and second means for applying, a DC component serving as a reverse bias of an internal electric field generated upon application of the gradation voltage signal, to the liquid crystal during one vertical scanning period.
A liquid crystal apparatus comprising a liquid crystal panel having a pair of electrodes and a liquid crystal exhibiting spontaneous polarization and arranged between said pair of electrodes, first means for applying a gradation voltage signal corresponding to gradation information to said pair of electrodes, and second means for applying, a DC component serving as a reverse bias of an internal electric field generated upon application of the gradation voltage signal, to said liquid crystal during one vertical scanning period.
A liquid crystal apparatus comprising:
A liquid crystal apparatus comprising:
A liquid crystal apparatus comprising:
A liquid crystal apparatus comprising:
A liquid crystal apparatus comprising:
Dependencies are inferred from the claim text.
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No related US applications are recorded in the indexed filing history.
By switched stationary formation of lamps, photocells or light relays: using cathode rays, e.g. multivision
Using an active matrix: using multistable liquid crystals, e.g. ferroelectric liquid crystals
Display of intermediate tones: by amplitude modulation
Display of intermediate tones: by domain size control
Term ended 7 Mar 2012 (estimated)
USPTO file history isn’t available for this patent, so only indexed dates are shown.
1. Field of the Invention
The present invention relates to a liquid crystal apparatus exhibiting spontaneous polarization and, more particularly, to a liquid crystal apparatus using a ferroelectric liquid crystal (FLC).
2. Related Background Art
FIG. 1 is a waveform chart of drive signals used in the present invention;
FIG. 2A is a sectional view of a cell used in the present invention;
FIG. 2B is an equivalent circuit diagram of the
A liquid crystal panel used in the present invention is a liquid crystal panel of an active matrix drive scheme, as shown in FIG. 17. The liquid crystal panel comprises switching elements (TFTs obtained by using thin film semiconductors such as amorphous silicon and polysilicon) arranged along a plurality of rows (scanning lines) and a plurality of columns (data lines), first wiring lines (gate lines) commonly connecting the first terminals (gates) of the switching elements in units of rows, second wiring lines (source lines) connecting the second terminals (sources) of the switching elements in units of columns, a plurality of pixel electrodes (transparent electrodes) connected in units of third terminals (drains) of the switching elements, counter electrodes (transparent electrodes) arranged to oppose the pixel electrodes, and a liquid crystal (chiral smectic C, H, I, G, F liquid crystal exhibiting ferroelectric properties) exhibiting spontaneous polarization and arranged between the plurality of pixel electrodes and the counter electrodes.
The distance between each pixel electrode and the corresponding counter electrode is set to be a minimum distance (about 5 .mu.m or less) capable of sufficiently suppressing formation of a helical structure of the chiral smectic liquid crystal. However, the formation of the helical structure need not be suppressed in the present invention.
Thermal control may be performed during driving of the liquid crystal to maintain the liquid crystal within a desired temperature range.