US3998522A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Screen for exhibiting projected images
Assignee: INTERCONTINENTAL SATELLITE NETWORK Inc
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Filing: 1975-03-24
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Granted: 1976-12-21
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Expires: 1995-03-24
Abstract
Abstract This disclosure teaches a screen such as those generally used for exhibiting projected images. A boxlike frame has a rim formed about its front. A membrane (the projection screen) covers the front with its margin extending to the vicinity of the rim. A cover encloses the back of the frame and is connected in sealed engagement to the margin of the membrane so as to form a plenum. Gas is withdrawn from the plenum whereby the membrane forms a concave image receiving surface curved in a relatively constant degree about a single point so that the image receiving surface takes on a spherical shape.
Inventors
- 👤 Thomas M. Holzel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 12:40
CPC Classifications
G; G03; G03B; G03B21/00; G03B21/54; G03B21/56
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
125 words
A screen for exhibiting projected images and comprising: a boxlike frame having a front and a back with a substantially rectangular rim about the front, a membrane covering the front and having a margin extending to the vicinity of the rim, a cover enclosing the back of the frame and connected in sealed engagement to the margin of the membrane at the rim so as to define a plenum, exhaust means for withdrawing gas from the plenum whereby the membrane forms a concave image receiving surface curved in a relatively constant degree about a single point so that the image receiving surface takes on a spherical shape, means for varying the withhdrawing of the gas from the plenum whereby said degree of curvature is variable.
Claim 2
Dependent Claim
125 words
A screen for exhibiting projected images and comprising: a boxlike frame having a front and a back with a substantially rectangular rim about the front, a membrane covering the front and having a margin extending to the vicinity of the rim, a cover enclosing the back of the frame and connected in sealed engagement to the margin of the membrane at the rim so as to define a plenum, exhaust means for withdrawing gas from the plenum whereby the membrane forms a concave image receiving surface curved in a relatively constant degree about a single point so that the image receiving surface takes on a spherical shape, means for varying the withhdrawing of the gas from the plenum whereby said degree of curvature is variable.
Claim 3
Dependent Claim
9 words
The screen of claim 1 with the rim concaved.
Claim 4
Dependent Claim
44 words
The screen of claim 1 with the rim including an upper and a lower edge as well as side edges, the upper and lower edges having the same curvature as each other and the two side edges having the same curvature as each other.
Claim 5
Dependent Claim
11 words
The screen of claim 3 with all of the curvatures hyperbolic.
References Cited (Backward Citations)
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Cited
US1526715A
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US2753818A
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US2906169A
Cited
US3037424A
Cited
US3936159A
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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) | 1979-12-21 | 1980-06-21 | 1980-12-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-12-21 | 1984-06-21 | 1984-12-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-12-21 | 1988-06-21 | 1988-12-21 | $7700.00 | Window Closed / Lapsed |