Patent US4692779A successfully refreshed from Google Patents.
US4692779A
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US
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Image forming method and apparatus therefor
Assignee: Canon Inc
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Filing: 1984-12-20
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Granted: 1987-09-08
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Expires: 2004-12-20
Abstract
Abstract A liquid crystal, particularly a ferroelectric liquid crystal, is interposed between an electroconductive member and an electric charge accepting member to form a liquid crystal device. In the first step of image formation, a uniform polarity of charge is imparted to the entirety or a part of the electric charge accepting member whereby the liquid crystal is uniformly oriented to its first stable state under a uniform electric field thus formed therethrough. In the second step, the reverse polarity of charges are given imagewise to the charge accepting member, whereby the liquid crystal is reoriented imagewise to the second stable state to form an image.
Inventors
- 👤 Yujiro Ando
- 👤 Shuzo Kaneko
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 22:23
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/133348; G02F1/137; G02F1/139; G02F1/141
Claims Analysis
Total Claims: 76
Claim 1
Independent Claim
71 words
An image forming apparatus comprising: a device which comprises an electroconductive member, an electric charge accepting member, and a liquid crystal interposed between the electroconductive member and the electric charge accepting member, and an ion generator for imparting an electric charge to the electric charge accepting member sufficient to form an electric field exceeding the threshold voltage of the liquid crystal between the electric charge accepting member and the electroconductive member.
Claim 2
Dependent Claim
71 words
An image forming apparatus comprising: a device which comprises an electroconductive member, an electric charge accepting member, and a liquid crystal interposed between the electroconductive member and the electric charge accepting member, and an ion generator for imparting an electric charge to the electric charge accepting member sufficient to form an electric field exceeding the threshold voltage of the liquid crystal between the electric charge accepting member and the electroconductive member.
Claim 3
Dependent Claim
18 words
The image forming apparatus according to claim 1, wherein said ion generator is capable of generating ion beams.
Claim 4
Dependent Claim
42 words
The image forming apparatus according to claim 2, wherein said liquid crystal is sealed in a cell structure comprising said electroconductive member and said electric charge accepting member, and the electroconductive member forms a counter electrode with respect to said ion generator.
Claim 5
Dependent Claim
24 words
The image forming apparatus according to claim 2, wherein said ion generator comprises a plurality of apertures for generating ion beams arranged in array.
Claim 6
Dependent Claim
24 words
The image forming apparatus according to claim 1, which further comprises means for moving said ion generator relative to said electric charge receiving member.
Claim 7
Dependent Claim
22 words
The image forming apparatus according to claim 1, wherein said electroconductive member is a transparent electroconductive film supported on a transparent substrate.
Claim 8
Dependent Claim
26 words
The image forming apparatus according to claim 1, wherein an orientation controlling film is provided on the side of the electroconductive member contacting the liquid crystal.
Claim 9
Dependent Claim
20 words
The image forming apparatus according to claim 1, wherein said charge accepting member comprises an organic or inorganic insulating material.
Claim 10
Dependent Claim
29 words
The image forming apparatus according to claim 1, wherein the electric field applied to the liquid crystal has an intensity ranging from 0.5×10 6 V/m to 10×10 6 V/m.
Claim 11
Dependent Claim
29 words
The image forming apparatus according to claim 1, wherein the electric charge imparted by said charging means ranges from 1.5×10 -5 coulomb/m 2 to 44×10 -5 coulomb/m 2 .
Claim 12
Dependent Claim
35 words
The image forming apparatus according to claim 2, wherein said ion generator has an aperture for generating ion beams having a diameter equal to or larger than the thickness of the electric charge accepting member.
Claim 13
Dependent Claim
30 words
The image forming apparatus according to claim 11, wherein the thickness of the electric charge accepting member is one half or less of the aperture diameter of the ion generator.
Claim 14
Dependent Claim
23 words
The image forming apparatus according to claim 1, wherein said electric charge accepting member has a resistivity of 10 10 ohm-cm or above.
Claim 15
Dependent Claim
24 words
The image forming apparatus according to claim 13, wherein said writing means comprises a plurality of apertures for generating ion beams arranged in array.
Claim 16
Dependent Claim
17 words
The image forming apparatus according to claim 1, wherein said liquid crystal is a ferroelectric liquid crystal.
Claim 17
Dependent Claim
19 words
The image forming apparatus according to claim 15, wherein said ferroelectric liquid crystal is a chiral smectic liquid crystal.
Claim 18
Dependent Claim
20 words
The image forming apparatus according to claim 15, wherein said ferroelectric liquid crystal is a bistable chiral smectic liquid crystal.
Claim 19
Dependent Claim
96 words
An image forming apparatus comprising: a device which comprises an electroconductive member, an electric charge accepting member, and a ferroelectric liquid crystal layer interposed between the electroconductive member and the electric charge accepting member, said device being capable of modulating a light transmitted therethrough, charging means for imparting an electric charge to the electric charge accepting member sufficient to form an electric field exceeding the threshold voltage of the liquid crystal between the electric charge accepting member and the electroconductive member, and polarizing means for detecting the modulated light transmitted through the ferroelectric liquid crystal layer.
Claim 20
Dependent Claim
96 words
An image forming apparatus comprising: a device which comprises an electroconductive member, an electric charge accepting member, and a ferroelectric liquid crystal layer interposed between the electroconductive member and the electric charge accepting member, said device being capable of modulating a light transmitted therethrough, charging means for imparting an electric charge to the electric charge accepting member sufficient to form an electric field exceeding the threshold voltage of the liquid crystal between the electric charge accepting member and the electroconductive member, and polarizing means for detecting the modulated light transmitted through the ferroelectric liquid crystal layer.
Claim 21
Dependent Claim
27 words
The image forming apparatus according to claim 18, wherein said light to be transmitted through said layer of ferroelectric liquid crystal is light polarized through polarizing means.
Claim 22
Dependent Claim
52 words
The image forming apparatus according to claim 18, which further comprises reflecting means for reflecting the modulated polarized light which has been transmitted through the ferroelectric liquid crystal layer, and a polarization beam splitter for detecting the modulated component of the modulated polarized light which has been reflected by the reflecting means.
Claim 23
Dependent Claim
31 words
The image forming apparatus according to claim 20, which further comprises a projecting screen on which the modulated component of the polarized light detected by the polarization beam splitter is projected.
Claim 24
Dependent Claim
16 words
The image forming apparatus according to claim 20, wherein said reflecting means is a dielectric mirror.
Claim 25
Dependent Claim
19 words
The image forming apparatus according to claim 18, wherein said ferroelectric liquid crystal is a bistable smectic liquid crystal.
Claim 26
Dependent Claim
19 words
The image forming apparatus according to claim 23, wherein said bistable liquid crystal is a chiral smectic liquid crystal.
Claim 27
Dependent Claim
18 words
The image forming apparatus according to claim 24, wherein said chiral smectic liquid crystal has a non-spiral structure.
Claim 28
Dependent Claim
18 words
The image forming apparatus according to claim 24, wherein said chiral smectic liquid crystal is C-phase or H-phase.
Claim 29
Dependent Claim
84 words
An image forming apparatus comprising: a device which comprises an electroconductive member, an electric charge accepting member, and a ferroelectric liquid crystal layer interposed between the electroconductive member and the electric charge accepting member, charging means for imparting an electric charge to the electric charge accepting member sufficient to form an electric field exceeding the threshold voltage of the liquid crystal between the electric charge accepting member and the electroconductive member, and a pair of polarizing means disposed outside the ferroelectric liquid crystal layer.
Claim 30
Dependent Claim
84 words
An image forming apparatus comprising: a device which comprises an electroconductive member, an electric charge accepting member, and a ferroelectric liquid crystal layer interposed between the electroconductive member and the electric charge accepting member, charging means for imparting an electric charge to the electric charge accepting member sufficient to form an electric field exceeding the threshold voltage of the liquid crystal between the electric charge accepting member and the electroconductive member, and a pair of polarizing means disposed outside the ferroelectric liquid crystal layer.
Claim 31
Dependent Claim
21 words
The image forming apparatus according to claim 27, wherein said pair of polarizing means are disposed in a cross nicol relationship.
Claim 32
Dependent Claim
25 words
The image forming apparatus according to claim 27, wherein one of said pair of polarizing means is also used as said electric charge accepting means.
Claim 33
Dependent Claim
28 words
The image forming apparatus according to claim 28, wherein one of said pair of polarizing means is disposed outside said charging means with respect to said liquid crystal.
Claim 34
Dependent Claim
19 words
The image forming apparatus according to claim 27, wherein said ferroelectric liquid crystal is a chiral smectic liquid crystal.
Claim 35
Dependent Claim
102 words
An image forming apparatus comprising: a liquid crystal device of a cell structure comprising an electroconductive member, an electric charge accepting member, and a layer of ferroelectric liquid crystal interposed between the electroconductive member and the electric charge accepting member, polarizing means for detecting modulated light which has been transmitted through the ferroelectric liquid crystal layer and optically modulated thereby, writing means for generating ion beams with said electroconductive member as a counter electrode and scanning the ion beams onto the electric charge accepting member to write an image in the liquid crystal layer, and erasing means for erasing the written image.
Claim 36
Dependent Claim
102 words
An image forming apparatus comprising: a liquid crystal device of a cell structure comprising an electroconductive member, an electric charge accepting member, and a layer of ferroelectric liquid crystal interposed between the electroconductive member and the electric charge accepting member, polarizing means for detecting modulated light which has been transmitted through the ferroelectric liquid crystal layer and optically modulated thereby, writing means for generating ion beams with said electroconductive member as a counter electrode and scanning the ion beams onto the electric charge accepting member to write an image in the liquid crystal layer, and erasing means for erasing the written image.
Claim 37
Dependent Claim
18 words
The image forming apparatus according to claim 32, wherein said erasing means comprises means for generating ion beams.
Claim 38
Dependent Claim
30 words
The image forming apparatus according to claim 33, wherein said erasing means generates ion beams with a polarity opposite to that of the ion beams generated from said writing means.
Claim 39
Dependent Claim
16 words
The image forming apparatus according to claim 32, wherein said erasing means comprises a corona discharger.
Claim 40
Dependent Claim
23 words
The image forming apparatus according to claim 32, wherein a pair of polarizing means are further provided outside the ferroelectric liquid crystal layer.
Claim 41
Dependent Claim
21 words
The image forming apparatus according to claim 36, wherein said pair of polarizing means are disposed in a cross nicol relationship.
Claim 42
Dependent Claim
19 words
The image forming apparatus according to claim 32, wherein said ferroelectric liquid crystal is a bistable smectic liquid crystal.
Claim 43
Dependent Claim
19 words
The image forming apparatus according to claim 38, wherein said bistable liquid crystal is a chiral smectic liquid crystal.
Claim 44
Dependent Claim
18 words
The image forming apparatus according to claim 39, wherein said chiral smectic liquid crystal has a non-spiral structure.
Claim 45
Dependent Claim
19 words
The image forming apparatus according to claim 39, wherein said chiral smectic liquid crystal is in C-phase or H-phase.
Claim 46
Dependent Claim
25 words
The image forming apparatus according to claim 32, which further comprises means for preventing deterioration of the liquid crystal device due to ion beam irradiation.
Claim 47
Dependent Claim
24 words
The image forming apparatus according to claim 32, which further comprises means for preventing deterioration of the writing means due to ion beam generator.
Claim 48
Dependent Claim
72 words
An image forming apparatus comprising: a device which comprises an electroconductive member, an electric charge accepting member, and a smectic liquid crystal interposed between the electroconductive member and the electric charge accepting member, heating means for heating the smectic liquid crystal into its isotropic phase, and an ion generator for generating ion beams with said electroconductive member as a counter electrode and irradiating the ion beams onto the electric charge accepting member.
Claim 49
Dependent Claim
72 words
An image forming apparatus comprising: a device which comprises an electroconductive member, an electric charge accepting member, and a smectic liquid crystal interposed between the electroconductive member and the electric charge accepting member, heating means for heating the smectic liquid crystal into its isotropic phase, and an ion generator for generating ion beams with said electroconductive member as a counter electrode and irradiating the ion beams onto the electric charge accepting member.
Claim 50
Dependent Claim
29 words
The image forming apparatus according to claim 44, wherein said smectic liquid crystal is sealed in a cell structure comprising said electroconductive member and said electric charge accepting member.
Claim 51
Dependent Claim
23 words
The image forming apparatus according to claim 44, wherein said smectic liquid crystal causes phase-transition through smectic phase, nematic phase and isotropic phase.
Claim 52
Dependent Claim
68 words
The image forming apparatus according to claim 45, wherein said electroconductive member is a transparent electroconductive film disposed in a stripe form on a transparent substrate, said stripe form transparent electroconductive film forming a counter electrode for successively generating ion beams and having a function of generating heat by electrical conduction therethrough, said electrical conduction being effected substantially simultaneously with or just prior to the ion beam irradiation.
Claim 53
Dependent Claim
24 words
The image forming apparatus according to claim 44, wherein said ion generator comprises a plurality of apertures for generating ion beams disposed in array.
Claim 54
Dependent Claim
199 words
An image forming method using a device comprising an electroconductive member, an electric charge accepting member and a ferroelectric liquid crystal having a first and a second stable state interposed between the electroconductive member and the electric charge accepting member, said image forming method comprising: a first step of imparting a uniform polarity of charge to the entirety or a part of the electric charge accepting member to form an electic field between the electroconductive member and the electric charge accepting member, whereby said ferroelectric liquid crystal is unformly oriented to its first stable state, a second step for image-writing comprising imparting imagewise charge of a polarity opposite to that of the charge imparted in the first step to the electric charge accepting member to form an electric field between the electric charge accepting member and the electroconductive member, whereby the liquid crystal oriented to the first stable state is partially oriented to its second stable state, a step of irradiating the ferroelectric liquid crystal oriented imagewise to its first and second stable states with polarized light having one polarization component to cause modulation of the polarized light, and a step of detecting the modulation to form an image.
Claim 55
Dependent Claim
199 words
An image forming method using a device comprising an electroconductive member, an electric charge accepting member and a ferroelectric liquid crystal having a first and a second stable state interposed between the electroconductive member and the electric charge accepting member, said image forming method comprising: a first step of imparting a uniform polarity of charge to the entirety or a part of the electric charge accepting member to form an electic field between the electroconductive member and the electric charge accepting member, whereby said ferroelectric liquid crystal is unformly oriented to its first stable state, a second step for image-writing comprising imparting imagewise charge of a polarity opposite to that of the charge imparted in the first step to the electric charge accepting member to form an electric field between the electric charge accepting member and the electroconductive member, whereby the liquid crystal oriented to the first stable state is partially oriented to its second stable state, a step of irradiating the ferroelectric liquid crystal oriented imagewise to its first and second stable states with polarized light having one polarization component to cause modulation of the polarized light, and a step of detecting the modulation to form an image.
Claim 56
Dependent Claim
20 words
The image forming method according to claim 49, wherein said ferroelectric liquid crystal is a bistable chiral smectic liquid crystal.
Claim 57
Dependent Claim
19 words
The image forming method according to claim 49, wherein said bistable liquid crystal is a chiral smectic liquid crystal.
Claim 58
Dependent Claim
18 words
The image forming method according to claim 50, wherein said chiral smectic liquid crystal has a non-spiral structure.
Claim 59
Dependent Claim
19 words
The image forming method according to claim 51, wherein said chiral smectic liquid crystal is in C-phase or H-phase.
Claim 60
Dependent Claim
56 words
The image forming method according to claim 49, wherein said polarized light having one polarization component and having passed through a polarization beam splitter is transmitted and reflected through a layer of the liquid crystal to cause the modulation, and the thus modulated light having the other polarization component is detected by the polarization beam splitter.
Claim 61
Dependent Claim
59 words
The image forming method according to claim 49, wherein a pair of polarizers are disposed outside a layer of the ferroelectric liquid crystal, polarized light having passed through one of said pair of polarizers is transmitted through the ferroelectric liquid crystal layer to be optically modulated, and the thus modulated polarized light is detected by the other polarizing means.
Claim 62
Dependent Claim
20 words
The image forming method according to claim 55, wherein said pair of polarizers are disposed in a cross nicol relationship.
Claim 63
Dependent Claim
35 words
The image forming method according to claim 49, wherein said electroconductive member is a transparent electrode film supported on a transparent substrate, which forms a cell structure in combination with the electric charge accepting member.
Claim 64
Dependent Claim
203 words
The image forming method according to claim 49, which comprises: a first step of irradiating a uniform polarity of ion beams to the entirety or a part of the electric charge accepting member to form an electric field between the electroconductive member and the electric charge accepting member, whereby said ferroelectric liquid crystal is uniformly oriented to its first stable state, a second step for image-writing comprising irradiating imagewise ion beams of a polarity opposite to that of the ion beams irradiated in the first step to the electric charge accepting member to form an electric field between the electroconductive member and the electric charge accepting member, whereby the liquid crystal oriented to the first stable state is partially oriented to its second stable state and an image is written, and a third step for image-erasure comprising irradiating a uniform polarity of ion beams to the entirety or a part of the electric charge accepting member to form an electric field between the electroconductive member and the electric charge accepting member, whereby said ferroelectric liquid crystal is uniformly oriented to one of said first and second stable states corresponding to the electric field and the image written in the second step is erased.
Claim 65
Dependent Claim
32 words
The image forming method according to claim 58, wherein said ion beams used in the third step have the same polarity as that of the ion beams used in the first step.
Claim 66
Dependent Claim
55 words
The image forming method according to claim 58, which further comprises a fourth step for re-writing comprising irradiating imagewise ion beams to the whole or a part of the portion irradiated in the third step of the electric charge accepting member, whereby an image is re-written in the corresponding part of the liquid crystal layer.
Claim 67
Dependent Claim
32 words
The image forming method according to claim 60, wherein the ion beams used in the fourth step has the same polarity as that of the ion beams used in the second step.
Claim 68
Dependent Claim
125 words
An image forming method using a device comprising an electroconductive member, an electric charge accepting member and a smectic liquid crystal interposed between the electroconductive member and the electric charge accepting method, said image forming method comprising: a first step of heating the smectic liquid crystal into its isotropic phase, and a second step of irradiating imagewise ion beams with said electroconductive member as a counter electrode to said electric charge accepting member under cooling, whereby said smectic liquid crystal is caused to form a transparent smectic phase at parts corresponding to the irradiated parts of the electric charge accepting member and to form a light-scattering smectic phase at parts corresponding to the nonirradiated parts of the electric charge accepting member, thereby writing an image.
Claim 69
Dependent Claim
125 words
An image forming method using a device comprising an electroconductive member, an electric charge accepting member and a smectic liquid crystal interposed between the electroconductive member and the electric charge accepting method, said image forming method comprising: a first step of heating the smectic liquid crystal into its isotropic phase, and a second step of irradiating imagewise ion beams with said electroconductive member as a counter electrode to said electric charge accepting member under cooling, whereby said smectic liquid crystal is caused to form a transparent smectic phase at parts corresponding to the irradiated parts of the electric charge accepting member and to form a light-scattering smectic phase at parts corresponding to the nonirradiated parts of the electric charge accepting member, thereby writing an image.
Claim 70
Dependent Claim
23 words
The image forming method according to claim 62, wherein said smectic liquid crystal causes phase-transition through smectic phase, nematic phase and isotropic phase.
Claim 71
Dependent Claim
171 words
The image forming method according to claim 62, which comprises: a first step of heating the smectic liquid crystal into its isotropic phase, and a second step of irradiating imagewise ion beams with said electroconductive member as a counter electrode to said electric charge accepting member under cooling, whereby said smectic liquid crystal is caused to form a transparent smectic phase at parts corresponding to the irradiated parts of the electric charge accepting member and to form a light-scattering smectic phase at parts corresponding to the nonirradiated parts of the electric charge accepting member, thereby writing an image, and a third step of heating the smectic liquid crystal into the isotropic phase and irradiating uniformly ion beams with the electroconductive member as a counter electrode to the entirety or a part of the electric charge accepting member under cooling to form a transparent smectic phase of the liquid crystal at parts corresponding to the irradiated parts of the electric charge accepting member, thereby erasing the image written in the second step.
Claim 72
Dependent Claim
24 words
The image forming method according to claim 64, wherein said first and second steps are repeated after said third step to write another image.
Claim 73
Dependent Claim
35 words
The image forming method according to claim 62, wherein said electroconductive member is a transparent electroconductive film supported on a transparent substrate, which forms a cell structure in combination with the electric charge accepting member.
Claim 74
Dependent Claim
180 words
An image forming method using a device comprising an electroconductive member, an electric charge accepting member and a ferroelectric liquid crystal having a first and a second stable state interposed between the electroconductive member and the electric charge accepting member, said image forming method comprising: a first step of imparting a uniform polarity of charge to the entirety or a part of the electric charge accepting member to form an electric field between the electroconductive member and the electric charge accepting member, whereby said ferroelectric liquid crystal is uniformly oriented to its first stable state, and a second steP for image-writing comprising imparting imagewise charge of a polarity opposite to that of the charge imparted in the first step to the electric charge accepting member to form an electric field between the electric charge accepting member and the electroconductive member, whereby the liquid crystal oriented to the first stable state is partially oriented to its second stable state; the electric charges in the first and second steps being imparted to the electric charge accepting member by irradiation of ion beams.
Claim 75
Dependent Claim
180 words
An image forming method using a device comprising an electroconductive member, an electric charge accepting member and a ferroelectric liquid crystal having a first and a second stable state interposed between the electroconductive member and the electric charge accepting member, said image forming method comprising: a first step of imparting a uniform polarity of charge to the entirety or a part of the electric charge accepting member to form an electric field between the electroconductive member and the electric charge accepting member, whereby said ferroelectric liquid crystal is uniformly oriented to its first stable state, and a second steP for image-writing comprising imparting imagewise charge of a polarity opposite to that of the charge imparted in the first step to the electric charge accepting member to form an electric field between the electric charge accepting member and the electroconductive member, whereby the liquid crystal oriented to the first stable state is partially oriented to its second stable state; the electric charges in the first and second steps being imparted to the electric charge accepting member by irradiation of ion beams.
Claim 76
Dependent Claim
20 words
The image forming method according to claim 67, wherein said ion beams are scanned over the electric charge accepting member.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1990-09-07 | 1991-03-09 | 1991-09-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-09-07 | 1995-03-09 | 1995-09-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-09-07 | 1999-03-09 | 1999-09-08 | $7700.00 | Window Closed / Lapsed |