US6804037B1
Expired / Lapsed
US
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Light modulation apparatus and image pickup apparatus, and drive method thereof
Assignee: Sony Corp
•
Filing: 2000-11-13
•
Granted: 2004-10-12
•
Expires: 2020-11-13
Abstract
Abstract Disclosed are a light modulation apparatus including a liquid crystal device; and a polarizing plate disposed in an optical path of light made incident on said liquid crystal device; wherein said liquid crystal device is of a guest-host type using a negative type liquid crystal as a host material, an image pickup apparatus using the light modulation apparatus, and methods of driving the light modulation apparatus and image pickup apparatus.
Inventors
- 👤 Keiichi Nito
- 👤 Toru Udaka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 12:01
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/137; G02F1/13725; G02F1/133; G02F1/13306; G02F1/13318; G02F1/1333; G02F1/1335; G02F1/133528; G02F1/13312; G02F1/13712; G09; G09G; G09G2320/00; G09G2320/04; G09G2320/041
Claims Analysis
Total Claims: 59
Claim 1
Independent Claim
177 words
An image pickup apparatus comprising: a liquid crystal device; a drive pulse generation unit for driving said liquid crystal device; a pulse width control unit for modulating a pulse width of each drive pulse to be applied to said liquid crystal device, thereby controlling a transmittance of light made incident on said liquid crystal device; a drive circuit unit; and a control circuit unit, wherein the modulation of the pulse width of each drive pulse is performed in a manner whereby the waveform of each drive pulse is present in a period of a basic frequency, each drive pulse whose waveform is present in the period of the basic frequency is generated in synchronization with a clock generated by said drive circuit unit, and luminance information of the light emerged from said liquid crystal device is fed back to said control circuit unit, and the pulse width of each drive pulse is modulated in synchronization with a clock generated by said drive circuit unit on the basis of a control signal supplied from said control circuit unit.
Claim 2
Dependent Claim
177 words
An image pickup apparatus comprising: a liquid crystal device; a drive pulse generation unit for driving said liquid crystal device; a pulse width control unit for modulating a pulse width of each drive pulse to be applied to said liquid crystal device, thereby controlling a transmittance of light made incident on said liquid crystal device; a drive circuit unit; and a control circuit unit, wherein the modulation of the pulse width of each drive pulse is performed in a manner whereby the waveform of each drive pulse is present in a period of a basic frequency, each drive pulse whose waveform is present in the period of the basic frequency is generated in synchronization with a clock generated by said drive circuit unit, and luminance information of the light emerged from said liquid crystal device is fed back to said control circuit unit, and the pulse width of each drive pulse is modulated in synchronization with a clock generated by said drive circuit unit on the basis of a control signal supplied from said control circuit unit.
Claim 3
Dependent Claim
25 words
A light modulation apparatus according to claim 1 , wherein the pulse width of each drive pulse is modulated with its pulse height kept constant.
Claim 4
Dependent Claim
47 words
A light modulation apparatus according to claim 1 , wherein an average per unit time of positive and negative pulse heights of drive pulses applied between drive electrodes of said liquid crystal device upon modulation of the pulse width of each drive pulse is preferably nearly zero.
Claim 5
Dependent Claim
39 words
A light modulation apparatus according to claim 1 , wherein the basic frequency and the modulated pulse width are adjusted in such a manner as to prevent the occurrence of flicker in stationary drive of said light modulation apparatus.
Claim 6
Dependent Claim
21 words
A light modulation apparatus according to claim 1 , wherein said liquid crystal device is a guest-host type liquid crystal device.
Claim 7
Dependent Claim
30 words
A light modulation apparatus according to claim 5 , wherein a host material is a negative or positive type liquid crystal having a negative or positive type dielectric constant anisotropy.
Claim 8
Dependent Claim
37 words
A light modulation apparatus according to claim 5 , wherein a guest material of said liquid crystal device is a positive or negative type dichroic dye molecular material having a positive or negative type light absorption anisotropy.
Claim 9
Dependent Claim
32 words
A light modulation apparatus according to claim 1 , wherein a drive electrode of said liquid crystal device is formed at least over the entire region of an effective light transmission portion.
Claim 10
Dependent Claim
98 words
An image pickup apparatus comprising: a light modulation apparatus including a liquid crystal device, a drive pulse generation unit for driving said liquid crystal device, and a pulse width control unit for modulating a pulse width of each drive pulse to be applied to said liquid crystal device, thereby controlling a transmittance of light made incident on said liquid crystal device; wherein said light modulation apparatus is disposed in an optical path of an optical system of said image pickup apparatus; and wherein the pulse width of each drive pulse is modulated with its pulse height kept constant.
Claim 11
Dependent Claim
98 words
An image pickup apparatus comprising: a light modulation apparatus including a liquid crystal device, a drive pulse generation unit for driving said liquid crystal device, and a pulse width control unit for modulating a pulse width of each drive pulse to be applied to said liquid crystal device, thereby controlling a transmittance of light made incident on said liquid crystal device; wherein said light modulation apparatus is disposed in an optical path of an optical system of said image pickup apparatus; and wherein the pulse width of each drive pulse is modulated with its pulse height kept constant.
Claim 12
Dependent Claim
120 words
An image pickup apparatus comprising: a light modulation apparatus including a liquid crystal device, a drive pulse generation unit for driving said liquid crystal device, and a pulse width control unit for modulating a pulse width of each drive pulse to be applied to said liquid crystal device, thereby controlling a transmittance of light made incident on said liquid crystal device; wherein said light modulation apparatus is disposed in an optical path of an optical system of said image pickup apparatus; and wherein an average per unit time of positive and negative pulse heights of drive pulses applied between drive electrodes of said liquid crystal device upon modulation of the pulse width of each drive pulse is preferably nearly zero.
Claim 13
Dependent Claim
120 words
An image pickup apparatus comprising: a light modulation apparatus including a liquid crystal device, a drive pulse generation unit for driving said liquid crystal device, and a pulse width control unit for modulating a pulse width of each drive pulse to be applied to said liquid crystal device, thereby controlling a transmittance of light made incident on said liquid crystal device; wherein said light modulation apparatus is disposed in an optical path of an optical system of said image pickup apparatus; and wherein an average per unit time of positive and negative pulse heights of drive pulses applied between drive electrodes of said liquid crystal device upon modulation of the pulse width of each drive pulse is preferably nearly zero.
Claim 14
Dependent Claim
115 words
An image pickup apparatus comprising: a light modulation apparatus including a liquid crystal device, a drive pulse generation unit for driving said liquid crystal device, and a pulse width control unit for modulating a pulse width of each drive pulse to be applied to said liquid crystal device, thereby controlling a transmittance of light made incident on said liquid crystal device; wherein said light modulation apparatus is disposed in an optical path of an optical system of said image pickup apparatus; and wherein the modulation of the pulse width of each drive pulse is performed in such a manner that the waveform of each drive pulse is present in a period of a basic frequency.
Claim 15
Dependent Claim
115 words
An image pickup apparatus comprising: a light modulation apparatus including a liquid crystal device, a drive pulse generation unit for driving said liquid crystal device, and a pulse width control unit for modulating a pulse width of each drive pulse to be applied to said liquid crystal device, thereby controlling a transmittance of light made incident on said liquid crystal device; wherein said light modulation apparatus is disposed in an optical path of an optical system of said image pickup apparatus; and wherein the modulation of the pulse width of each drive pulse is performed in such a manner that the waveform of each drive pulse is present in a period of a basic frequency.
Claim 16
Dependent Claim
39 words
An image pickup apparatus according to claim 11 , wherein the basic frequency and the modulated pulse width are adjusted in such a manner as to prevent the occurrence of flicker in stationary drive of said light modulation apparatus.
Claim 17
Dependent Claim
43 words
An image pickup apparatus according to claim 11 , further comprising a drive circuit unit, wherein each drive pulse whose waveform is present in the period of the basic frequency is generated in synchronization with a clock generated by said drive circuit unit.
Claim 18
Dependent Claim
69 words
An image pickup apparatus according to claim 12 , further comprising a control circuit unit, wherein luminance information of the light emerged from said liquid crystal device is fed back to said control circuit unit, and the pulse width of each drive pulse is modulated in synchronization with a clock generated by said drive circuit unit on the basis of a control signal supplied from said control circuit unit.
Claim 19
Dependent Claim
94 words
An image pickup apparatus comprising: a light modulation apparatus including a liquid crystal device, a drive pulse generation unit for driving said liquid crystal device, and a pulse width control unit for modulating a pulse width of each drive pulse to be applied to said liquid crystal device, thereby controlling a transmittance of light made incident on said liquid crystal device; wherein said light modulation apparatus is disposed in an optical path of an optical system of said image pickup apparatus; and wherein said liquid crystal device is a guest-host type liquid crystal device.
Claim 20
Dependent Claim
94 words
An image pickup apparatus comprising: a light modulation apparatus including a liquid crystal device, a drive pulse generation unit for driving said liquid crystal device, and a pulse width control unit for modulating a pulse width of each drive pulse to be applied to said liquid crystal device, thereby controlling a transmittance of light made incident on said liquid crystal device; wherein said light modulation apparatus is disposed in an optical path of an optical system of said image pickup apparatus; and wherein said liquid crystal device is a guest-host type liquid crystal device.
Claim 21
Dependent Claim
30 words
An image pickup apparatus according to claim 15 , wherein a host material is a negative or positive type liquid crystal having a negative or positive type dielectric constant anisotropy.
Claim 22
Dependent Claim
37 words
An image pickup apparatus according to claim 15 , wherein a guest material of said liquid crystal device is a positive or negative type dichroic dye molecular material having a positive or negative type light absorption anisotropy.
Claim 23
Dependent Claim
99 words
An image pickup apparatus comprising: a light modulation apparatus including a liquid crystal device, a drive pulse generation unit for driving said liquid crystal device, and a pulse width control unit for modulating a pulse width of each drive pulse to be applied to said liquid crystal device, thereby controlling a transmittance of light made incident on said liquid crystal device; and a polarizing plate disposed in an optical path of light made incident on said liquid crystal device; wherein said light modulation apparatus is disposed in an optical path of an optical system of said image pickup apparatus.
Claim 24
Dependent Claim
99 words
An image pickup apparatus comprising: a light modulation apparatus including a liquid crystal device, a drive pulse generation unit for driving said liquid crystal device, and a pulse width control unit for modulating a pulse width of each drive pulse to be applied to said liquid crystal device, thereby controlling a transmittance of light made incident on said liquid crystal device; and a polarizing plate disposed in an optical path of light made incident on said liquid crystal device; wherein said light modulation apparatus is disposed in an optical path of an optical system of said image pickup apparatus.
Claim 25
Dependent Claim
21 words
An image pickup apparatus according to claim 18 , wherein said polarizing plate is movable in or from the optical path.
Claim 26
Dependent Claim
47 words
An image pickup apparatus according to claim 19 , wherein said polarizing plate is disposed in a movable portion of a mechanical iris in such a manner as to be movable in or from the optical path by operation of said movable portion of said mechanical iris.
Claim 27
Independent Claim
171 words
A method of driving an image pickup apparatus including a liquid crystal device, comprising the step of: modulating a pulse width of each drive pulse to be applied to said liquid crystal device, thereby controlling a transmittance of light made incident on said liquid crystal device, wherein the modulation of the pulse width of each drive pulse is performed in a manner whereby the waveform of each drive pulse is present in a period of a basic frequency, each drive pulse whose waveform is present in the period of the basic frequency is generated in synchronization with a clock generated by a drive circuit unit provided in said light modulation apparatus, and luminance information of the light emerged from said liquid crystal device is fed back to a control circuit unit provided in said light modulation apparatus, and the pulse width of each drive pulse is modulated in synchronization with a clock generated by said drive circuit unit on the basis of a control signal supplied from said control circuit unit.
Claim 28
Independent Claim
171 words
A method of driving an image pickup apparatus including a liquid crystal device, comprising the step of: modulating a pulse width of each drive pulse to be applied to said liquid crystal device, thereby controlling a transmittance of light made incident on said liquid crystal device, wherein the modulation of the pulse width of each drive pulse is performed in a manner whereby the waveform of each drive pulse is present in a period of a basic frequency, each drive pulse whose waveform is present in the period of the basic frequency is generated in synchronization with a clock generated by a drive circuit unit provided in said light modulation apparatus, and luminance information of the light emerged from said liquid crystal device is fed back to a control circuit unit provided in said light modulation apparatus, and the pulse width of each drive pulse is modulated in synchronization with a clock generated by said drive circuit unit on the basis of a control signal supplied from said control circuit unit.
Claim 29
Dependent Claim
29 words
A method of driving a light modulation apparatus according to claim 21 , wherein the pulse width of each drive pulse is modulated with its pulse height kept constant.
Claim 30
Dependent Claim
51 words
A method of driving a light modulation apparatus according to claim 21 , wherein an average per unit time of positive and negative pulse heights of drive pulses applied between drive electrodes of said liquid crystal device upon modulation of the pulse width of each drive pulse is preferably nearly zero.
Claim 31
Dependent Claim
42 words
A method of driving a light modulation apparatus according to claim 21 , wherein the basic frequency and the modulated pulse width adjusted in such a manner as to prevent the occurrence of flicker in stationary drive of said light modulation apparatus.
Claim 32
Dependent Claim
25 words
A method of driving a light modulation apparatus according to claim 21 , wherein said liquid crystal device is a guest-host type liquid crystal device.
Claim 33
Dependent Claim
39 words
A method of driving a light modulation apparatus according to claim 25 , wherein a host material of said liquid crystal device is a negative or positive type liquid crystal having a negative or positive type dielectric constant anisotropy.
Claim 34
Dependent Claim
41 words
A method of driving a light modulation apparatus according to claim 25 , wherein a guest material of said liquid crystal device is a positive or negative type dichroic dye molecular material having a positive or negative type light absorption anisotropy.
Claim 35
Dependent Claim
36 words
A method of driving a light modulation apparatus according to claim 21 , wherein a drive electrode of said liquid crystal device is formed at least over the entire region of an effective light transmission portion.
Claim 36
Independent Claim
78 words
A method of driving an image pickup apparatus in which a liquid crystal device is disposed in an optical path of an optical system of said image pickup apparatus, comprising the step of: modulating a pulse width of each drive pulse to be applied to said liquid crystal device, thereby controlling a transmittance of light made incident on said liquid crystal device; wherein the pulse width of each drive pulse is modulated with its pulse height kept constant.
Claim 37
Independent Claim
78 words
A method of driving an image pickup apparatus in which a liquid crystal device is disposed in an optical path of an optical system of said image pickup apparatus, comprising the step of: modulating a pulse width of each drive pulse to be applied to said liquid crystal device, thereby controlling a transmittance of light made incident on said liquid crystal device; wherein the pulse width of each drive pulse is modulated with its pulse height kept constant.
Claim 38
Independent Claim
100 words
A method of driving an image pickup apparatus in which a liquid crystal device is disposed in an optical path of an optical system of said image pickup apparatus, comprising the step of: modulating a pulse width of each drive pulse to be applied to said liquid crystal device, thereby controlling a transmittance of light made incident on said liquid crystal device; wherein an average per unit time of positive and negative pulse heights of drive pulses applied between drive electrodes of said liquid crystal device upon modulation of the pulse width of each drive pulse is preferably nearly zero.
Claim 39
Independent Claim
100 words
A method of driving an image pickup apparatus in which a liquid crystal device is disposed in an optical path of an optical system of said image pickup apparatus, comprising the step of: modulating a pulse width of each drive pulse to be applied to said liquid crystal device, thereby controlling a transmittance of light made incident on said liquid crystal device; wherein an average per unit time of positive and negative pulse heights of drive pulses applied between drive electrodes of said liquid crystal device upon modulation of the pulse width of each drive pulse is preferably nearly zero.
Claim 40
Independent Claim
95 words
A method of driving an image pickup apparatus in which a liquid crystal device is disposed in an optical path of an optical system of said image pickup apparatus, comprising the step of: modulating a pulse width of each drive pulse to be applied to said liquid crystal device, thereby controlling a transmittance of light made incident on said liquid crystal device; wherein the modulation of the pulse width of each drive pulse is performed in such a manner that the waveform of each drive pulse is present in a period of a basic frequency.
Claim 41
Independent Claim
95 words
A method of driving an image pickup apparatus in which a liquid crystal device is disposed in an optical path of an optical system of said image pickup apparatus, comprising the step of: modulating a pulse width of each drive pulse to be applied to said liquid crystal device, thereby controlling a transmittance of light made incident on said liquid crystal device; wherein the modulation of the pulse width of each drive pulse is performed in such a manner that the waveform of each drive pulse is present in a period of a basic frequency.
Claim 42
Dependent Claim
43 words
A method of driving an image pickup apparatus according to claim 31 , wherein the basic frequency and the modulated pulse width are adjusted in such a manner as to prevent the occurrence of flicker in stationary drive of said light modulation apparatus.
Claim 43
Dependent Claim
47 words
A method of driving an image pickup apparatus according to claim 31 , wherein each drive pulse whose waveform is present in the period of the basic frequency is generated in synchronization with a clock generated by a drive circuit unit provided in said light modulation apparatus.
Claim 44
Independent Claim
122 words
A method of driving an image pickup apparatus in which a liquid crystal device is disposed in an optical path of an optical system of said image pickup apparatus, comprising the step of: modulating a pulse width of each drive pulse to be applied to said liquid crystal device, thereby controlling a transmittance of light made incident on said liquid crystal device; wherein luminance information of the light emerged from said liquid crystal device is fed back to a control circuit unit provided in said light modulation apparatus, and the pulse width of each drive pulse is modulated in synchronization with a clock generated by said drive circuit unit on the basis of a control signal supplied from said control circuit unit.
Claim 45
Independent Claim
122 words
A method of driving an image pickup apparatus in which a liquid crystal device is disposed in an optical path of an optical system of said image pickup apparatus, comprising the step of: modulating a pulse width of each drive pulse to be applied to said liquid crystal device, thereby controlling a transmittance of light made incident on said liquid crystal device; wherein luminance information of the light emerged from said liquid crystal device is fed back to a control circuit unit provided in said light modulation apparatus, and the pulse width of each drive pulse is modulated in synchronization with a clock generated by said drive circuit unit on the basis of a control signal supplied from said control circuit unit.
Claim 46
Independent Claim
74 words
A method of driving an image pickup apparatus in which a liquid crystal device is disposed in an optical path of an optical system of said image pickup apparatus, comprising the step of: modulating a pulse width of each drive pulse to be applied to said liquid crystal device, thereby controlling a transmittance of light made incident on said liquid crystal device; wherein said liquid crystal device is a guest-host type liquid crystal device.
Claim 47
Independent Claim
74 words
A method of driving an image pickup apparatus in which a liquid crystal device is disposed in an optical path of an optical system of said image pickup apparatus, comprising the step of: modulating a pulse width of each drive pulse to be applied to said liquid crystal device, thereby controlling a transmittance of light made incident on said liquid crystal device; wherein said liquid crystal device is a guest-host type liquid crystal device.
Claim 48
Dependent Claim
39 words
A method of driving an image pickup apparatus according to claim 35 , wherein a host material of said liquid crystal device is a negative or positive type liquid crystal having a negative or positive type dielectric constant anisotropy.
Claim 49
Dependent Claim
41 words
A method of driving an image pickup apparatus according to claim 35 , wherein a guest material of said liquid crystal device is a positive or negative type dichroic dye molecular material having a positive or negative type light absorption anisotropy.
Claim 50
Independent Claim
81 words
A method of driving an image pickup apparatus in which a liquid crystal device is disposed in an optical path of an optical system of said image pickup apparatus, comprising the step of: modulating a pulse width of each drive pulse to be applied to said liquid crystal device, thereby controlling a transmittance of light made incident on said liquid crystal device; wherein a polarizing plate is disposed in an optical path of light made incident on said liquid crystal device.
Claim 51
Independent Claim
81 words
A method of driving an image pickup apparatus in which a liquid crystal device is disposed in an optical path of an optical system of said image pickup apparatus, comprising the step of: modulating a pulse width of each drive pulse to be applied to said liquid crystal device, thereby controlling a transmittance of light made incident on said liquid crystal device; wherein a polarizing plate is disposed in an optical path of light made incident on said liquid crystal device.
Claim 52
Dependent Claim
25 words
A method of driving an image pickup apparatus according to claim 38 , wherein said polarizing plate is movable in or from the optical path.
Claim 53
Dependent Claim
51 words
A method of driving an image pickup apparatus according to claim 39 , wherein said polarizing plate is disposed in a movable portion of a mechanical iris in such a manner as to be movable in or from the optical path by operation of said movable portion of said mechanical iris.
Claim 54
Independent Claim
85 words
A method of driving an image pickup apparatus in which a liquid crystal device is disposed in an optical path of an optical system of said image pickup apparatus, comprising the step of: modulating a pulse width of each drive pulse to be applied to said liquid crystal device, thereby controlling a transmittance of light made incident on said liquid crystal device; wherein a drive electrode of said liquid crystal device is formed at least over the entire region of an effective light transmission portion.
Claim 55
Independent Claim
85 words
A method of driving an image pickup apparatus in which a liquid crystal device is disposed in an optical path of an optical system of said image pickup apparatus, comprising the step of: modulating a pulse width of each drive pulse to be applied to said liquid crystal device, thereby controlling a transmittance of light made incident on said liquid crystal device; wherein a drive electrode of said liquid crystal device is formed at least over the entire region of an effective light transmission portion.
Claim 56
Dependent Claim
122 words
A light modulation apparatus comprising: a liquid crystal device; a drive pulse generation unit for driving said liquid crystal device; a pulse width control unit for modulating a pulse width of each drive pulse to be applied to said liquid crystal device, thereby controlling a transmittance of light made incident on said liquid crystal device; and a polarizing plate disposed in an optical path of light made incident on said liquid crystal device, wherein said polarizing plate is movable in or from the optical path, and said polarizing plate is disposed in a movable portion of a mechanical iris in a manner whereby it is movable in or from the optical path by operation of said movable portion of said mechanical iris.
Claim 57
Dependent Claim
122 words
A light modulation apparatus comprising: a liquid crystal device; a drive pulse generation unit for driving said liquid crystal device; a pulse width control unit for modulating a pulse width of each drive pulse to be applied to said liquid crystal device, thereby controlling a transmittance of light made incident on said liquid crystal device; and a polarizing plate disposed in an optical path of light made incident on said liquid crystal device, wherein said polarizing plate is movable in or from the optical path, and said polarizing plate is disposed in a movable portion of a mechanical iris in a manner whereby it is movable in or from the optical path by operation of said movable portion of said mechanical iris.
Claim 58
Independent Claim
113 words
A method of driving a light modulation apparatus including a liquid crystal device, comprising the step of: modulating a pulse width of each drive pulse to be applied to said liquid crystal device, thereby controlling a transmittance of light made incident on said liquid crystal device, wherein a polarizing plate is disposed in an optical path of light made incident on said liquid crystal device, said polarizing plate is movable in or from the optical path, and said polarizing plate is disposed in a movable portion of a mechanical iris in a manner whereby it is movable in or from the optical path by operation of said movable portion of said mechanical iris.
Claim 59
Independent Claim
113 words
A method of driving a light modulation apparatus including a liquid crystal device, comprising the step of: modulating a pulse width of each drive pulse to be applied to said liquid crystal device, thereby controlling a transmittance of light made incident on said liquid crystal device, wherein a polarizing plate is disposed in an optical path of light made incident on said liquid crystal device, said polarizing plate is movable in or from the optical path, and said polarizing plate is disposed in a movable portion of a mechanical iris in a manner whereby it is movable in or from the optical path by operation of said movable portion of said mechanical iris.
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