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US5396352A Expired / Lapsed US ⏱️ 0.0 years remaining

Liquid crystal apparatus with gradation information signals and DC bias

Assignee: Canon Inc
•
Filing: 1991-08-16
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Granted: 1995-03-07
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Expires: 2011-08-16
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Abstract

Abstract 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.

Inventors

  • 👤 Shuzo Kaneko
  • 👤 Ryoji Fujiwara
  • 👤 Akio Yoshida
  • 👤 Tomoro Maruyama

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 20:47
CPC Classifications
H; H04; H04N; H04N3/00; H04N3/10; H04N3/12; H04N3/122; G; G09; G09G; G09G3/00; G09G3/20; G09G3/34; G09G3/36; G09G3/3611; G09G3/3648; G09G3/3651; G09G2310/00; G09G2310/06; G09G2310/061; G09G2310/065; G09G3/2007; G09G3/2011; G09G3/207

Claims Analysis

Total Claims: 34
Claim 1
Independent Claim 80 words
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.
Claim 2
Dependent Claim 80 words
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.
Claim 3
Dependent Claim 17 words
An apparatus according to claim 1, wherein said liquid crystal essentially consists of a ferroelectric liquid crystal.
Claim 4
Dependent Claim 17 words
An apparatus according to claim 1, wherein said one vertical scanning period is one frame scanning period.
Claim 5
Dependent Claim 26 words
An apparatus according to claim 1, wherein a value of the DC component is within a range of 1/50 to 1/5 of the gradation voltage signal.
Claim 6
Dependent Claim 172 words
A liquid crystal apparatus comprising: a. a liquid crystal panel having switching elements arranged along a plurality of rows and a plurality of columns, first wiring lines commonly connecting first terminals of said switching elements in units of rows, second wiring lines commonly connecting second terminals of said switching elements in units of columns, a plurality of pixel electrodes connected in units of third terminals of said switching elements, counter electrodes opposite to said pixel electrodes, and a liquid crystal exhibiting spontaneous polarization and sandwiched between said plurality of pixel electrodes and said counter electrodes; b. first means for applying scanning pulses to said first wiring lines; and c. second means for applying a gradation voltage signal corresponding to gradation information to said second wiring lines and for applying an auxiliary voltage signal to said second wiring lines so that a DC component serving as a reverse bias for an internal electric field generated upon application of the gradation voltage signal is applied to said liquid crystal during one vertical scanning period.
Claim 7
Dependent Claim 172 words
A liquid crystal apparatus comprising: a. a liquid crystal panel having switching elements arranged along a plurality of rows and a plurality of columns, first wiring lines commonly connecting first terminals of said switching elements in units of rows, second wiring lines commonly connecting second terminals of said switching elements in units of columns, a plurality of pixel electrodes connected in units of third terminals of said switching elements, counter electrodes opposite to said pixel electrodes, and a liquid crystal exhibiting spontaneous polarization and sandwiched between said plurality of pixel electrodes and said counter electrodes; b. first means for applying scanning pulses to said first wiring lines; and c. second means for applying a gradation voltage signal corresponding to gradation information to said second wiring lines and for applying an auxiliary voltage signal to said second wiring lines so that a DC component serving as a reverse bias for an internal electric field generated upon application of the gradation voltage signal is applied to said liquid crystal during one vertical scanning period.
Claim 8
Dependent Claim 17 words
An apparatus according to claim 5, wherein said liquid crystal essentially consists of a ferroelectric liquid crystal.
Claim 9
Dependent Claim 17 words
An apparatus according to claim 5, wherein said one vertical scanning period is one frame scanning period.
Claim 10
Dependent Claim 26 words
An apparatus according to claim 5, wherein a value of the DC component is within a range of 1/50 to 1/5 of the gradation voltage signal.
Claim 11
Dependent Claim 178 words
A liquid crystal apparatus comprising: a. a liquid crystal panel having switching elements arranged along a plurality of rows and a plurality of columns, first wiring lines commonly connecting first terminals of said switching elements in units of rows, second wiring lines commonly connecting second terminals of said switching elements in units of columns, a plurality of pixel electrodes connected in units of third terminals of said switching elements, counter electrodes opposite to said pixel electrodes, and a liquid crystal exhibiting spontaneous polarization and sandwiched between said plurality of pixel electrodes and said counter electrodes; b. first means for applying scanning pulses to said first wiring lines; and c. second means for applying a voltage signal corresponding to gradation information to said second wiring lines after a reset voltage signal is applied and for applying an auxiliary voltage signal to said second wiring lines such that a DC component serving as a reverse bias for an internal electric field generated upon application of the gradation voltage signal is applied to said liquid crystal during one vertical scanning period.
Claim 12
Dependent Claim 178 words
A liquid crystal apparatus comprising: a. a liquid crystal panel having switching elements arranged along a plurality of rows and a plurality of columns, first wiring lines commonly connecting first terminals of said switching elements in units of rows, second wiring lines commonly connecting second terminals of said switching elements in units of columns, a plurality of pixel electrodes connected in units of third terminals of said switching elements, counter electrodes opposite to said pixel electrodes, and a liquid crystal exhibiting spontaneous polarization and sandwiched between said plurality of pixel electrodes and said counter electrodes; b. first means for applying scanning pulses to said first wiring lines; and c. second means for applying a voltage signal corresponding to gradation information to said second wiring lines after a reset voltage signal is applied and for applying an auxiliary voltage signal to said second wiring lines such that a DC component serving as a reverse bias for an internal electric field generated upon application of the gradation voltage signal is applied to said liquid crystal during one vertical scanning period.
Claim 13
Dependent Claim 17 words
An apparatus according to claim 9, wherein said liquid crystal essentially consists of a ferroelectric liquid crystal.
Claim 14
Dependent Claim 17 words
An apparatus according to claim 9, wherein said one vertical scanning period is one frame scanning period.
Claim 15
Dependent Claim 26 words
An apparatus according to claim 9, wherein a value of the DC component is within a range of 1/50 to 1/5 of the gradation voltage signal.
Claim 16
Dependent Claim 47 words
An apparatus according to claim 9, further comprising means for applying, prior to application of the reset voltage signal, a voltage signal given such that a difference between an absolute value of the reset voltage signal and an absolute value of the gradation voltage signal becomes zero.
Claim 17
Dependent Claim 27 words
An apparatus according to claim 9, further comprising means for applying a zero voltage during a period between the auxiliary voltage signal and the gradation voltage signal.
Claim 18
Dependent Claim 128 words
A liquid crystal apparatus comprising: a liquid crystal element having a liquid crystal having spontaneous polarization, a pair of electrode substrates for sandwiching said liquid crystal therebetween, and insulating layers formed between said electrode substrates and said liquid crystal, wherein a spontaneous polarization ##EQU24## value of said liquid crystal, an interelectrode composite capacitance ##EQU25## of Vth (units of V) of optical response of said liquid crystal in said liquid crystal element satisfy the following condition: ##EQU26## 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 gradations voltage signal, to said liquid crystal during one vertical scanning period.
Claim 19
Dependent Claim 128 words
A liquid crystal apparatus comprising: a liquid crystal element having a liquid crystal having spontaneous polarization, a pair of electrode substrates for sandwiching said liquid crystal therebetween, and insulating layers formed between said electrode substrates and said liquid crystal, wherein a spontaneous polarization ##EQU24## value of said liquid crystal, an interelectrode composite capacitance ##EQU25## of Vth (units of V) of optical response of said liquid crystal in said liquid crystal element satisfy the following condition: ##EQU26## 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 gradations voltage signal, to said liquid crystal during one vertical scanning period.
Claim 20
Dependent Claim 17 words
An apparatus according to claim 15, wherein said liquid crystal essentially consists of a ferroelectric liquid crystal.
Claim 21
Dependent Claim 17 words
An apparatus according to claim 15, wherein said one vertical scanning period is one frame scanning period.
Claim 22
Dependent Claim 26 words
An apparatus according to claim 15, wherein a value of the DC component is within a range of 1/50 to 1/5 of the gradation voltage signal.
Claim 23
Dependent Claim 220 words
A liquid crystal apparatus comprising: a. a liquid crystal element having switching elements arranged along a plurality of rows and a plurality of columns, first wiring lines commonly connecting first terminals of said switching elements in units of rows, second wiring lines commonly connecting second terminals of said switching elements in units of columns, a plurality of pixel electrodes connected in units of third terminals of said switching elements, counter electrodes opposite to said pixel electrodes, a liquid crystal exhibiting spontaneous polarization P S (nC/cm 2 ) sandwiched between said plurality of pixel electrodes and said counter electrodes, and an insulating member formed on at least one of said pixel and counter electrodes, a voltage threshold value Vth (V) of optical response of said liquid crystal and an interelectrode capacitance Ci (nF/cm 2 ) of said insulating member satisfying the following condition: ##EQU27## b. first means for applying scanning pulses to said first wiring lines; and c. second means for applying a gradation voltage signal corresponding to gradation information to said second wiring lines and for applying an auxiliary voltage signal to said second wiring lines so that a DC component serving as a reverse bias for an internal electric field generated upon application of the gradation voltage signal is applied to said liquid crystal during one vertical scanning period.
Claim 24
Dependent Claim 220 words
A liquid crystal apparatus comprising: a. a liquid crystal element having switching elements arranged along a plurality of rows and a plurality of columns, first wiring lines commonly connecting first terminals of said switching elements in units of rows, second wiring lines commonly connecting second terminals of said switching elements in units of columns, a plurality of pixel electrodes connected in units of third terminals of said switching elements, counter electrodes opposite to said pixel electrodes, a liquid crystal exhibiting spontaneous polarization P S (nC/cm 2 ) sandwiched between said plurality of pixel electrodes and said counter electrodes, and an insulating member formed on at least one of said pixel and counter electrodes, a voltage threshold value Vth (V) of optical response of said liquid crystal and an interelectrode capacitance Ci (nF/cm 2 ) of said insulating member satisfying the following condition: ##EQU27## b. first means for applying scanning pulses to said first wiring lines; and c. second means for applying a gradation voltage signal corresponding to gradation information to said second wiring lines and for applying an auxiliary voltage signal to said second wiring lines so that a DC component serving as a reverse bias for an internal electric field generated upon application of the gradation voltage signal is applied to said liquid crystal during one vertical scanning period.
Claim 25
Dependent Claim 17 words
An apparatus according to claim 19, wherein said liquid crystal essentially consists of a ferroelectric liquid crystal.
Claim 26
Dependent Claim 17 words
An apparatus according to claim 19, wherein said one vertical scanning period is one frame scanning period.
Claim 27
Dependent Claim 26 words
An apparatus according to claim 19, wherein a value of the DC component is within a range of 1/50 to 1/5 of the gradation voltage signal.
Claim 28
Dependent Claim 226 words
A liquid crystal apparatus comprising: a. a liquid crystal element having switching elements arranged along a plurality of rows and a plurality of columns, first wiring lines commonly connecting first terminals of said switching elements in units of rows, second wiring lines commonly connecting second terminals of said switching elements in units of columns, a plurality of pixel electrodes connected in units of third terminals of said switching elements, counter electrodes opposite to said pixel electrodes, a liquid crystal exhibiting spontaneous polarization P S (nC/cm 2 ) and sandwiched between said plurality of pixel electrodes and said counter electrodes, and an insulating member formed on at least one of said pixel and counter electrodes, a voltage threshold value Vth (V) of liquid crystal of said optical response and an interelectrode capacitance Ci (nF/cm 2 ) said insulating member satisfying the following condition: ##EQU28## b. first means for applying scanning pulses to said first wiring lines; and c. second means for applying a voltage signal corresponding to gradation information to said second wiring lines after a reset voltage signal is applied and for applying an auxiliary voltage signal to said second wiring lines such that a DC component serving as a reverse bias for an internal electric field generated upon application of the gradation voltage signal is applied to said liquid crystal during one vertical scanning period.
Claim 29
Dependent Claim 226 words
A liquid crystal apparatus comprising: a. a liquid crystal element having switching elements arranged along a plurality of rows and a plurality of columns, first wiring lines commonly connecting first terminals of said switching elements in units of rows, second wiring lines commonly connecting second terminals of said switching elements in units of columns, a plurality of pixel electrodes connected in units of third terminals of said switching elements, counter electrodes opposite to said pixel electrodes, a liquid crystal exhibiting spontaneous polarization P S (nC/cm 2 ) and sandwiched between said plurality of pixel electrodes and said counter electrodes, and an insulating member formed on at least one of said pixel and counter electrodes, a voltage threshold value Vth (V) of liquid crystal of said optical response and an interelectrode capacitance Ci (nF/cm 2 ) said insulating member satisfying the following condition: ##EQU28## b. first means for applying scanning pulses to said first wiring lines; and c. second means for applying a voltage signal corresponding to gradation information to said second wiring lines after a reset voltage signal is applied and for applying an auxiliary voltage signal to said second wiring lines such that a DC component serving as a reverse bias for an internal electric field generated upon application of the gradation voltage signal is applied to said liquid crystal during one vertical scanning period.
Claim 30
Dependent Claim 17 words
An apparatus according to claim 23, wherein said liquid crystal essentially consists of a ferroelectric liquid crystal.
Claim 31
Dependent Claim 17 words
An apparatus according to claim 23, wherein said one vertical scanning period is one frame scanning period.
Claim 32
Dependent Claim 26 words
An apparatus according to claim 23, wherein a value of the DC component is within a range of 1/50 to 1/5 of the gradation voltage signal.
Claim 33
Dependent Claim 47 words
An apparatus according to claim 23, further comprising means for applying, prior to application of the reset voltage signal, a voltage signal given such that a difference between an absolute value of the reset voltage signal and an absolute value of the gradation voltage signal becomes zero.
Claim 34
Dependent Claim 27 words
An apparatus according to claim 23, further comprising means for applying a zero voltage during a period between the auxiliary voltage signal and the gradation voltage signal.

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