US3701249A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Solid state timepiece with liquid crystal display
Assignee: Hamilton Watch Co
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Filing: 1971-03-12
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Granted: 1972-10-31
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Expires: 1991-03-12
Abstract
Abstract Disclosed is a solid state wristwatch having an improved liquid crystal time display. Solid state time-keeping components are continuously energized from a low voltage battery while the display is energized only on demand from a separate high voltage battery. The direction of current flow through the liquid crystals is reversed during display to improve display life. A highly polished mirror surface is provided on the outside of the back plate of the thin glass sandwich where it is not in contact with the liquid crystal material.
Inventors
- 👤 John M Bergey
- 👤 Eric L Blouch
- 👤 Richard S Walton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 10:37
CPC Classifications
G; G04; G04G; G04G9/00; G04G9/0023; G04G9/0029; G04G9/0047; G04G9/08; G04G9/12
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
47 words
A timekeeping device having sufficiently small size for use as a wristwatch comprising an electrical timing source, an optical time display, a time computer coupling said timing source to said time display, a power source, and a polarity reverser coupling said power source to said time display.
Claim 2
Dependent Claim
47 words
A timekeeping device having sufficiently small size for use as a wristwatch comprising an electrical timing source, an optical time display, a time computer coupling said timing source to said time display, a power source, and a polarity reverser coupling said power source to said time display.
Claim 3
Dependent Claim
15 words
A device according to claim 1 wherein said time display is a liquid crystal display.
Claim 4
Dependent Claim
20 words
A device according to claim 2 including a second power source coupled to said timing source and said time computer.
Claim 5
Dependent Claim
23 words
A device according to claim 3 including means for continuously coupling said second power source to said timing source and said time computer.
Claim 6
Dependent Claim
14 words
A device according to claim 1 wherein said timing source comprises a crystal oscillator.
Claim 7
Dependent Claim
20 words
A device according to claim 1 wherein said time computer comprises a frequency divider and optical display decoder and driver.
Claim 8
Dependent Claim
27 words
A device according to claim 1 wherein said polarity reverser is coupled to said timing source whereby the current flow through said display may be continually reversed.
Claim 9
Dependent Claim
40 words
A device according to claim 1 wherein said display comprises a liquid crystal sandwich construction including a liquid crystal material sandwiched between spaced front and back plates, and a layer of highly polished mirror surface material on said back plate.
Claim 10
Dependent Claim
13 words
A device according to claim 8 wherein said layer comprises an aluminum film.
Claim 11
Dependent Claim
78 words
A timekeeping device having sufficiently small size for use as a wristwatch comprising a high frequency electrical timing source, a liquid crystal time display, a digital time computer coupling said timing source to said liquid crystal display, a first low voltage power source continuously coupled to said time computer, a second high voltage power source, and a demand switch coupling said high voltage power source to said liquid crystal display whereby said display is only actuated on demand.
Claim 12
Dependent Claim
78 words
A timekeeping device having sufficiently small size for use as a wristwatch comprising a high frequency electrical timing source, a liquid crystal time display, a digital time computer coupling said timing source to said liquid crystal display, a first low voltage power source continuously coupled to said time computer, a second high voltage power source, and a demand switch coupling said high voltage power source to said liquid crystal display whereby said display is only actuated on demand.
Claim 13
Dependent Claim
19 words
A device according to claim 10 wherein said low voltage power source comprises a high capacity silver oxide cell.
Claim 14
Dependent Claim
17 words
A device according to claim 11 wherein said high voltage power source comprises a solid state battery.
Claim 15
Dependent Claim
21 words
A device according to claim 12 wherein said battery produces from 9 to 30 volts at about 1 milliampere hours minimum.
Claim 16
Dependent Claim
28 words
A device according to claim 10 including a polarity reverser coupling said liquid crystal display to said time computer whereby the potential across said display is continually reversed.
Claim 17
Dependent Claim
53 words
In an electronic wristwatch, a timing source, a liquid crystal display, a high voltage battery, a time computer coupled to said timing source and a demand switch coupling said battery to said display whereby said display is energized only on demand, and including a polarity reverser coupling said display to said time computer.
Claim 18
Dependent Claim
53 words
In an electronic wristwatch, a timing source, a liquid crystal display, a high voltage battery, a time computer coupled to said timing source and a demand switch coupling said battery to said display whereby said display is energized only on demand, and including a polarity reverser coupling said display to said time computer.
Claim 19
Dependent Claim
21 words
Apparatus according to claim 15 wherein said reverser comprises a plurality of of solid state bidirectional gates coupled to said display.
Claim 20
Dependent Claim
22 words
Apparatus according to claim 16 wherein said display comprises a plurality of liquid crystal elements arranged to form a decimal digital display.
Claim 21
Dependent Claim
13 words
Apparatus according to claim 17 wherein said elements comprise liquid crystal bar segments.
Claim 22
Dependent Claim
24 words
Apparatus according to claim 18 including a separate gate for each of said segments, and a flip-flop coupling said time computer to said gates.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-10-31 | 1976-05-01 | 1976-10-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-31 | 1980-05-01 | 1980-10-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-31 | 1984-05-01 | 1984-10-31 | $7700.00 | Window Closed / Lapsed |