← Back to Patent Explorer
US5058995A Expired / Lapsed US ⏱️ 0.0 years remaining

Pixel electrode structure for liquid crystal display devices

Assignee: Thomson Licensing SAS
•
Filing: 1990-03-15
•
Granted: 1991-10-22
•
Expires: 2010-03-15
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A liquid crystal pixel electrode and a thin film transistor (TFT) structure includes a select line, a portion of which is coated with undoped solid state material. The select line is parallel to a continuous uninterrupted side of the pixel electrode and a data line is parallel to another continuous uninterrupted side of the pixel electrode. A source area and a drain area of doped solid state material are placed over the undoped layer. The source area contacts the data line and the drain area contacts the pixel electrode. The select line also serves as the gate electrode of the TFT. A notch passes through the undoped material between the data line and the drain to prevent leakage.

Inventors

  • 👤 Dora Plus

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 04:54
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/136; G02F1/1362; G02F1/1368

Claims Analysis

Total Claims: 16
Claim 1
Independent Claim 175 words
A liquid crystal pixel electrode structure comprising: an insulative substrate; a select line supported on said substrate; an insulative material coating said select line; a region of undoped solid state material on said insulative material coating and overlaying a length of said select line; a source area of doped solid state material overlaying a first portion of said region and extending beyond said select line; a drain area of doped solid state material overlaying a second portion of said region and spaced from said source area to form a channel between said source and drain areas; a data line in electrical contact with said source area and extending substantially perpendicular to said select line; a pixel electrode having a first continuous uniterrupted side in electrical contact with said drain area and having a second continuous uninterrupted side spaced from said data line; and a notch passing through said doped and undoped solid state material and positioned between said data line and said drain area for preventing leakage between said data line and said drain area.
Claim 2
Dependent Claim 175 words
A liquid crystal pixel electrode structure comprising: an insulative substrate; a select line supported on said substrate; an insulative material coating said select line; a region of undoped solid state material on said insulative material coating and overlaying a length of said select line; a source area of doped solid state material overlaying a first portion of said region and extending beyond said select line; a drain area of doped solid state material overlaying a second portion of said region and spaced from said source area to form a channel between said source and drain areas; a data line in electrical contact with said source area and extending substantially perpendicular to said select line; a pixel electrode having a first continuous uniterrupted side in electrical contact with said drain area and having a second continuous uninterrupted side spaced from said data line; and a notch passing through said doped and undoped solid state material and positioned between said data line and said drain area for preventing leakage between said data line and said drain area.
Claim 3
Dependent Claim 16 words
The pixel electrode structure of claim 1 wherein said undoped solid state material is amorphous silicon.
Claim 4
Dependent Claim 16 words
The pixel electrode structure of claim 2 wherein said doped solid state material is amorphous silicon.
Claim 5
Dependent Claim 16 words
The pixel electrode structure of claim 1 wherein said doped solid state material is amorphous silicon.
Claim 6
Dependent Claim 15 words
The pixel electrode structure of claim 1 wherein said undoped solid state material is polysilicon.
Claim 7
Dependent Claim 15 words
The pixel electrode structure of claim 2 wherein said doped solid state material is polysilicon.
Claim 8
Dependent Claim 15 words
The pixel electrode structure of claim 1 wherein said doped solid state material is polysilicon.
Claim 9
Dependent Claim 192 words
A thin film transistor (TFT) and pixel electrode structure for a liquid crystal display comprising: an insulative substrate; a common select line and TFT gate electrode supported on said substrate; an insulative coating on said select line and gate electrode; a region of undoped solid state material on said insulative coating and overlaying a length of said select line and gate electrode; a source for said TFT comprised of doped solid state material overlaying a first portion of said region and extending beyond said select line; a drain for said TFT comprised of doped solid state material overlaying a second portion of said region and spaced from said source to form a channel between said source and said drain; a data line in electrical contact with said source and extending substantially perpendicular to said select line; a pixel electrode having a first continuous uninterrupted side in electrical contact with said drain and having a second continuous uninterrupted side spaced from said data line; and a notch passing through said undoped solid state material and positioned between said data line and said drain for preventing leakage between said data line and said drain.
Claim 10
Dependent Claim 192 words
A thin film transistor (TFT) and pixel electrode structure for a liquid crystal display comprising: an insulative substrate; a common select line and TFT gate electrode supported on said substrate; an insulative coating on said select line and gate electrode; a region of undoped solid state material on said insulative coating and overlaying a length of said select line and gate electrode; a source for said TFT comprised of doped solid state material overlaying a first portion of said region and extending beyond said select line; a drain for said TFT comprised of doped solid state material overlaying a second portion of said region and spaced from said source to form a channel between said source and said drain; a data line in electrical contact with said source and extending substantially perpendicular to said select line; a pixel electrode having a first continuous uninterrupted side in electrical contact with said drain and having a second continuous uninterrupted side spaced from said data line; and a notch passing through said undoped solid state material and positioned between said data line and said drain for preventing leakage between said data line and said drain.
Claim 11
Dependent Claim 16 words
The pixel electrode structure of claim 8 wherein said undoped solid state material is amorphous silicon.
Claim 12
Dependent Claim 16 words
The pixel electrode structure of claim 9 wherein said doped solid state material is amorphous silicon.
Claim 13
Dependent Claim 16 words
The pixel electrode structure of claim 8 wherein said doped solid state material is amorphous silicon.
Claim 14
Dependent Claim 15 words
The pixel electrode structure of claim 8 wherein said undoped solid state material is polysilicon.
Claim 15
Dependent Claim 15 words
The pixel electrode structure of claim 12 wherein said doped solid state material is polysilicon.
Claim 16
Dependent Claim 15 words
The pixel electrode structure of claim 8 wherein said doped solid state material is polysilicon.

References Cited (Backward Citations)

EP0090661A2 Cited
US4720736A Cited
US4705358A Cited
US4686553A Cited
US4889411A Cited
US4857907A Cited
US4862234A Cited
US4961629A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1994-10-21 1995-04-22 1995-10-22 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1998-10-21 1999-04-22 1999-10-22 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2002-10-21 2003-04-22 2003-10-22 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag