US3998535A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Resilient frame construction for displaying transparencies
Assignee: Individual
•
Filing: 1975-07-31
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Granted: 1976-12-21
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Expires: 1995-07-31
Abstract
Abstract An improved frame construction for supporting transparencies for projection by an overhead optical projector, including means for maintaining a transparency in fixed position relative to the projector, and means for selectively adding color to desired areas of the transparency for directing the attention of the viewer, and adding interest to the display. The colored areas may be oriented in either of two mutually perpendicular directions.
Inventors
- 👤 Jim Clarke
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 22:18
CPC Classifications
G; G03; G03B; G03B21/00; G03B21/132; Y; Y10; Y10S; Y10S353/00; Y10S353/05
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
189 words
An improved frame construction for use in supporting transparencies in position for projection by an overhead optical projector comprising: a relatively rigid rectangular transparent sheet of material bounded by a pair of shorter edges, a pair of longer edges, and first and second parallel surfaces; a first pair of resiliently flexible planar strips of substantial thickness secured to said first surface of said sheet, each strip abutting one of said longer edges of said sheet at one edge of said strip and having a second parallel edge facing the corresponding edge of the other strip to define a channel for the selective engagement and frictional retention of a display sheet; a second pair of resilient flexible planar strips of substantial thickness secured to said second surface of said sheet, each strip abutting one of said shorter edges of said sheet along one edge of said strip, and having a second parallel edge facing the corresponding edge of the other of said second pair of strips to define a second channel for the selective engagement of said display sheet, the axis of said first and second channels being mutually perpendicular.
Claim 2
Dependent Claim
189 words
An improved frame construction for use in supporting transparencies in position for projection by an overhead optical projector comprising: a relatively rigid rectangular transparent sheet of material bounded by a pair of shorter edges, a pair of longer edges, and first and second parallel surfaces; a first pair of resiliently flexible planar strips of substantial thickness secured to said first surface of said sheet, each strip abutting one of said longer edges of said sheet at one edge of said strip and having a second parallel edge facing the corresponding edge of the other strip to define a channel for the selective engagement and frictional retention of a display sheet; a second pair of resilient flexible planar strips of substantial thickness secured to said second surface of said sheet, each strip abutting one of said shorter edges of said sheet along one edge of said strip, and having a second parallel edge facing the corresponding edge of the other of said second pair of strips to define a second channel for the selective engagement of said display sheet, the axis of said first and second channels being mutually perpendicular.
Claim 3
Dependent Claim
35 words
Structure in accordance with claim 1, including a plurality of colored transparent members selectively positioned upon planar surfaces of a pair of said strips to be frictionally retained thereby and extend across a channel therebetween.
Claim 4
Dependent Claim
27 words
Structure in accordance with claim 1, further characterized in said first pair of strips and said second pair of strips being of different widths to facilitate identification.
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) | 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 |