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US4671642A Expired / Lapsed US ⏱️ 0.0 years remaining

Image forming apparatus

Assignee: Canon Inc
•
Filing: 1985-04-24
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Granted: 1987-06-09
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Expires: 2005-04-24
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Abstract

Abstract An image forming apparatus of the type comprising a liquid crystal panel having a first substrate having first electrodes thereon, a liquid crystal layer, a second substrate having a second electrode, polarizing means and light-scattering reflection means; a light source for emitting light toward the liquid crystal from the side of the first substrate; means for forming an electrostatic light image corresponding to the light rays reflected from the liquid crystal panel; and developing means. Picture elements are arranged in a row or column with a spacing (P) between adjacent picture elements, each picture element being formed at a portion where the first and second electrodes face each other through the liquid crystal layer, the gap (P) being equal to or larger than the distance (D) from the interface between the second electrode and the liquid crystal layer to the scattering reflection surface of the light-scattering reflection means.

Inventors

  • 👤 Yukitoshi Ohkubo
  • 👤 Shuzo Kaneko
  • 👤 Junichiro Kanbe

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-06 05:33
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/60; G03G15/605; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/1343; G02F1/134309; G02F1/134336; G02F1/136; G02F1/1362; G02F1/1368; G03G15/50; G03G15/5016

Claims Analysis

Total Claims: 20
Claim 1
Independent Claim 152 words
In an image forming apparatus of the type comprising a liquid crystal panel having a first substrate having first electrodes thereon, a liquid crystal layer, a second substrate having a second electrode, polarizing means and light-scattering reflection means; a light source for emitting light toward said liquid crystal from the side of said first substrate; means for forming an electrostatic light image corresponding to the light rays reflected from said liquid crystal panel; and developing means; the improvement wherein picture elements are arranged in a row or column with a spacing (P) between adjacent picture elements, each picture element being formed at a portion where said first and second electrodes face each other through the liquid crystal layer, said gap (P) being equal to or larger than the distance (D) from the interface between said second electrode and said liquid crystal layer to the scattering reflection surface of said light-scattering reflection means.
Claim 2
Dependent Claim 152 words
In an image forming apparatus of the type comprising a liquid crystal panel having a first substrate having first electrodes thereon, a liquid crystal layer, a second substrate having a second electrode, polarizing means and light-scattering reflection means; a light source for emitting light toward said liquid crystal from the side of said first substrate; means for forming an electrostatic light image corresponding to the light rays reflected from said liquid crystal panel; and developing means; the improvement wherein picture elements are arranged in a row or column with a spacing (P) between adjacent picture elements, each picture element being formed at a portion where said first and second electrodes face each other through the liquid crystal layer, said gap (P) being equal to or larger than the distance (D) from the interface between said second electrode and said liquid crystal layer to the scattering reflection surface of said light-scattering reflection means.
Claim 3
Dependent Claim 34 words
An image forming apparatus according to claim 1 wherein said first electrodes are plural in number and arranged in a matrix, and a thin film transistor is connected to each of said first electrodes.
Claim 4
Dependent Claim 19 words
An image forming apparatus according to claim 2 wherein the thin film transistors are disposed on said first substrate.
Claim 5
Dependent Claim 22 words
An image forming apparatus according to claim 2 wherein the semiconductor part of each of said thin film transistors comprises amorphous silicon.
Claim 6
Dependent Claim 20 words
An image forming apparatus according to claim 1 wherein said polarizing means comprises two polarizers disposed in a cross-nicol relationship.
Claim 7
Dependent Claim 35 words
An image forming apparatus according to claim 1 wherein said distance D is within a range of from 50 to 200 micrometers; and the number of picture elements per millimeter is between 20 and 5.
Claim 8
Dependent Claim 25 words
An image forming apparatus according to claim 1 wherein the spacing P of the picture elements and the distance D satisfy the relationship of D/P<1/2.
Claim 9
Dependent Claim 132 words
In an image forming apparatus of the type comprising a liquid crystal panel having a first substrate having first electrodes thereon, a liquid crystal layer, a second substrate having a second electrode, polarizing means and light-scattering reflection means; a light source for emitting light toward said liquid crystal from the side of said first substrate; means for forming an electrostatic light image corresponding to the light rays reflected from said liquid crystal panel; and developing means: the improvement wherein said first electrodes are plural in number and arranged in a matrix, each first electrode being connected to a thin film transistor, and the electrodes formed on the first substrate provided with the thin film transistors except for those formed on the semiconductors of the thin film transistors are formed of transparent electrodes.
Claim 10
Dependent Claim 132 words
In an image forming apparatus of the type comprising a liquid crystal panel having a first substrate having first electrodes thereon, a liquid crystal layer, a second substrate having a second electrode, polarizing means and light-scattering reflection means; a light source for emitting light toward said liquid crystal from the side of said first substrate; means for forming an electrostatic light image corresponding to the light rays reflected from said liquid crystal panel; and developing means: the improvement wherein said first electrodes are plural in number and arranged in a matrix, each first electrode being connected to a thin film transistor, and the electrodes formed on the first substrate provided with the thin film transistors except for those formed on the semiconductors of the thin film transistors are formed of transparent electrodes.
Claim 11
Dependent Claim 26 words
An image forming apparatus according to claim 8 wherein the terminals of each of said thin film transistors are made of a metal or an alloy.
Claim 12
Dependent Claim 21 words
An image forming apparatus according to claim 8 wherein the semiconductor of each of said thin film transistors comprises amorphous silicon.
Claim 13
Dependent Claim 20 words
An image forming apparatus according to claim 8 wherein said polarizing means comprises two polarizers disposed in a cross-nicol relationship.
Claim 14
Dependent Claim 149 words
In an image forming apparatus of the type comprising a liquid crystal panel having a first substrate having first electrodes thereon, a liquid crystal layer, a second substrate having a second electrode, polarizing means and light-scattering reflection means; a light source for emitting light toward said liquid crystal from the side of said first substrate; means for forming an electrostatic light image corresponding to the light rays reflected from said liquid crystal panel; and developing means; the improvement wherein picture elements are arranged in a row or column, each picture element being formed at a portion where said first and second electrodes face each other through the liquid crystal layer, said first electrodes or second electrode at the picture elements is connected to an opaque wiring part comprising a metal or an alloy, and light-transmissive scattering means is provided for scattering a shadow formed by the opaque wiring part.
Claim 15
Dependent Claim 149 words
In an image forming apparatus of the type comprising a liquid crystal panel having a first substrate having first electrodes thereon, a liquid crystal layer, a second substrate having a second electrode, polarizing means and light-scattering reflection means; a light source for emitting light toward said liquid crystal from the side of said first substrate; means for forming an electrostatic light image corresponding to the light rays reflected from said liquid crystal panel; and developing means; the improvement wherein picture elements are arranged in a row or column, each picture element being formed at a portion where said first and second electrodes face each other through the liquid crystal layer, said first electrodes or second electrode at the picture elements is connected to an opaque wiring part comprising a metal or an alloy, and light-transmissive scattering means is provided for scattering a shadow formed by the opaque wiring part.
Claim 16
Dependent Claim 28 words
An image forming apparatus according to claim 12 wherein said light-transmissive scattering means is disposed at a position corresponding to said opaque wiring part of said first substrate.
Claim 17
Dependent Claim 34 words
An image forming apparatus according to claim 12 wherein said first electrodes are plural in number and arranged in a matrix, and a thin film transistor is connected to each of said first electrodes.
Claim 18
Dependent Claim 19 words
An image forming apparatus according to claim 14 wherein the thin film transistors are formed on said first substrate.
Claim 19
Dependent Claim 20 words
An image forming apparatus according to claim 14 wherein the semiconductor part of said thin film transistor comprises amorphous silicon.
Claim 20
Dependent Claim 20 words
An image forming apparatus according to claim 14 wherein said polarizing means comprises two polarizers disposed in a cross-nicol relationship.

References Cited (Backward Citations)

US3936172A Cited
US4080058A Cited
US4099855A Cited
US4110794A Cited
US4194833A Cited
US4448867A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-06-08 1990-12-08 1991-06-09 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-06-08 1994-12-08 1995-06-09 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-06-08 1998-12-08 1999-06-09 $7700.00 Window Closed / Lapsed

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