US3782104A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Timer having a color-display system
Assignee: HAMPTON-HADDEN MARKETING Corp A CORP OF
•
Filing: 1972-08-10
•
Granted: 1974-01-01
•
Expires: 1992-08-10
Abstract
Abstract A color-display system embodied in a clock mechanism wherein the face of the clock constantly changes color. A pair of transparent, light-polarizing sheets are arranged parallel to one another with one of the sheets forming the face of the clock. A pair of birefringent sheets are positioned between the polarizing sheets with one of the sheets having a greater retardance than the other. The one sheet is arranged with one of the principal axes at a fixed 45-degree angle relative to each of the polarizing axes. The other birefringent sheet is supported for rotation about an axis normal to the first birefringent sheet. Rotation of this birefringent sheet by the clock mechanism effectively changes the color of the clock face.
Inventors
- 👤 J Kirsch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 08:31
CPC Classifications
G; G02; G02B; G02B27/00; G02B27/28; G02B27/288; G04; G04B; G04B19/00; G04B19/30; G04B45/00; G04B45/0023
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
129 words
A color-display clock comprising a pair of bighttransmitting, polarizing sheets arranged parallel to one another, and each having a polarizing axis, a pair of birefringent sheet means, each interposed between said polarizing sheets and each having a set of principal axis, one of said birefringent sheet means having greater retardance than the other, said one sheet means being fixed relative to said polarizing sheets with one of its principal axes at an angle of 45* to the polarizing axis of each of said polarizing sheets, hands, one of said polarizing sheets comprising a face of said clock, means for rotating said other birefringent sheet means about an axis normal to said one birefringent sheet means, and means securing at least one of said hands to said means for rotating.
Claim 2
Dependent Claim
129 words
A color-display clock comprising a pair of bighttransmitting, polarizing sheets arranged parallel to one another, and each having a polarizing axis, a pair of birefringent sheet means, each interposed between said polarizing sheets and each having a set of principal axis, one of said birefringent sheet means having greater retardance than the other, said one sheet means being fixed relative to said polarizing sheets with one of its principal axes at an angle of 45* to the polarizing axis of each of said polarizing sheets, hands, one of said polarizing sheets comprising a face of said clock, means for rotating said other birefringent sheet means about an axis normal to said one birefringent sheet means, and means securing at least one of said hands to said means for rotating.
Claim 3
Dependent Claim
22 words
A clock as set forth in claim 1 wherein the hour, minute and second hands are each formed of a birefringent material.
Claim 4
Dependent Claim
18 words
A clock as set forth in claim 1 including means forming a hole in said other birefringent sheet.
Claim 5
Dependent Claim
24 words
A clock as set forth in claim 1 including illumination means disposed adjacent said one polarizing sheet and remote from the other polarizing sheet.
Claim 6
Dependent Claim
26 words
A clock as set forth in claim 4 wherein said illumination means comprises a plurality of lamps spacedly disposed about a center axis of the clock.
Claim 7
Dependent Claim
40 words
A clock as set forth in claim 5 comprising common support means, wherein said means for rotating includes a motor and said lamps and motor are carried by said common support means with said lamps disposed radially of said motor.
Claim 8
Dependent Claim
40 words
A clock as set forth in claim 1 wherein said hands include a minute hand and an hour hand, said other birefringent sheet being circular and forming a second hand, all said hands being secured to said means for rotating.
Claim 9
Dependent Claim
19 words
A clock as set forth in claim 7 comprising a pair of glass sheets sandwiching said other polarizing sheet.
Claim 10
Dependent Claim
22 words
A clock as set forth in claim 3 wherein said hole is formed near the outer edge of said other birefringent sheet.
Claim 11
Dependent Claim
20 words
A clock as set forth in claim 1 including at least one of said hands formed of a birefringent material.
References Cited (Backward Citations)
US2146962A
Cited
US2184999A
Cited
US2393968A
Cited
US2506134A
Cited
US2473857A
Cited
US2527593A
Cited
US3431044A
Cited
US3321905A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-12-31 | 1977-07-02 | 1978-01-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-31 | 1981-07-02 | 1982-01-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-31 | 1985-07-02 | 1986-01-01 | $7700.00 | Window Closed / Lapsed |