US4990900A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Touch panel
Assignee: Alps Alpine Co Ltd
•
Filing: 1988-06-09
•
Granted: 1991-02-05
•
Expires: 2008-06-09
Abstract
Abstract A touch panel having a panel body formed by transparent upper and lower electrodes spaced a predetermined distance. The touch panel is mounted on a front surface of a display device to detect a coordinate at a depressed position on the upper electrode. The improvement comprises a transparent insulating liquid material filled between the upper and lower electrodes and a coloring agent containing pigment or dyestuff dispersed in the liquid material. In another aspect, the improvement comprises a transparent insulating liquid material filled between the upper and lower electrodes and an insulating fine powder dispersed in the liquid material.
Inventors
- 👤 Hiroshi Kikuchi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 08:23
CPC Classifications
G; G06; G06F; G06F3/00; G06F3/01; G06F3/03; G06F3/041; G06F3/045
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
72 words
In a touch panel having a panel body formed by transparent upper and lower electrodes spaced a predetermined distance, said touch panel being mounted on a front surface of a display device to detect a coordinate at a depressed position on said upper electrode; the improvement comprising a transparent insulating liquid material filled between said upper and lower electrodes and a coloring agent containing pigment or dyestuff dispersed in said liquid material.
Claim 2
Dependent Claim
72 words
In a touch panel having a panel body formed by transparent upper and lower electrodes spaced a predetermined distance, said touch panel being mounted on a front surface of a display device to detect a coordinate at a depressed position on said upper electrode; the improvement comprising a transparent insulating liquid material filled between said upper and lower electrodes and a coloring agent containing pigment or dyestuff dispersed in said liquid material.
Claim 3
Dependent Claim
30 words
The touch panel as defined in claim 1, further comprising an insulating fine powder dispensened in said liquid material and wherein said insulating fine powder comprises a transparent spherical powder.
Claim 4
Dependent Claim
42 words
The touch panel as defined in claim 2, wherein said insulating fine powder is comprised of spheres having a diameter about equal to a spacing between said upper and said lower electrodes when said upper electrode is not in the depressed position.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-02-04 | 1994-08-06 | 1995-02-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-02-04 | 1998-08-06 | 1999-02-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-02-04 | 2002-08-06 | 2003-02-05 | $7700.00 | Window Closed / Lapsed |