Patent US3346674A successfully refreshed from Google Patents.
US3346674A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for fabricating backlit projection screens
Assignee: Fma Inc
•
Filing: 1962-12-04
•
Granted: 1967-10-10
•
Expires: 1982-12-04
Abstract
No abstract record available.
Inventors
- 👤 Harvey L Kidder
- 👤 Poul B Roulund
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 15:25
CPC Classifications
G; G03; G03B; G03B21/00; G03B21/54; G03B21/56; G03B21/60; G03B21/62; G03B21/625
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
138 words
A METHOD OF FABRICATING A PROJECTION SCREEN HAVING A SURFACE COVERED WITH A LAYER OF TINY RANDOMLY DISTRIBUTED HEMISPHERICAL LENSES, SAID METHOD COMPRISING THE STEPS OF: PLACING A FIRST FLUID SUBSTANCE THAT WILL HARDEN INTO A RESILIENT SOLID INTO A CONTAINER OF SUITABLE CONFIGURATION; CURING SAID FIRST SUBSTANCES UNTIL ITS CONSISTENCY IS TACKY; FORMING A HALF-IMMERSED LAYER OF TINY SPHERES ON THE SURFACE OF SAID CURED SUBSTANCE; FURTHER CURING SAID FIRST SUBSTANCE UNIT IT HARDENS INTO A FIRST RESILIENT SOLID; PLACING A SECOND FLUID SUBSTANCE THAT WILL HARDEN INTO A RESILIENT SOLID OVER SAID LAYER OF SPHERE; CURING SAID SECOND SUBSTANCE UNTIL IT HARDENS INTO A SECOND RESILIENT SOLID; SEPARATING SADI SECOND RESILIENT SOLID FROM SAID LAYER OF SPHERES, THEREBY PRODUCING A MOLD WHOSE SURFACE IS COVERED WITH HEMISPHERICAL RECESSES; AND MOLDING THE PROJECTION SCREEN FROM SAID MOLD.
Claim 2
Independent Claim
138 words
A METHOD OF FABRICATING A PROJECTION SCREEN HAVING A SURFACE COVERED WITH A LAYER OF TINY RANDOMLY DISTRIBUTED HEMISPHERICAL LENSES, SAID METHOD COMPRISING THE STEPS OF: PLACING A FIRST FLUID SUBSTANCE THAT WILL HARDEN INTO A RESILIENT SOLID INTO A CONTAINER OF SUITABLE CONFIGURATION; CURING SAID FIRST SUBSTANCES UNTIL ITS CONSISTENCY IS TACKY; FORMING A HALF-IMMERSED LAYER OF TINY SPHERES ON THE SURFACE OF SAID CURED SUBSTANCE; FURTHER CURING SAID FIRST SUBSTANCE UNIT IT HARDENS INTO A FIRST RESILIENT SOLID; PLACING A SECOND FLUID SUBSTANCE THAT WILL HARDEN INTO A RESILIENT SOLID OVER SAID LAYER OF SPHERE; CURING SAID SECOND SUBSTANCE UNTIL IT HARDENS INTO A SECOND RESILIENT SOLID; SEPARATING SADI SECOND RESILIENT SOLID FROM SAID LAYER OF SPHERES, THEREBY PRODUCING A MOLD WHOSE SURFACE IS COVERED WITH HEMISPHERICAL RECESSES; AND MOLDING THE PROJECTION SCREEN FROM SAID MOLD.
References Cited (Backward Citations)
US2248638A
Cited
US2248811A
Cited
US2378252A
Cited
US2498489A
Cited
US2936814A
Cited
US3164645A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1970-10-09 | 1971-04-10 | 1971-10-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-10-09 | 1975-04-10 | 1975-10-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-10-09 | 1979-04-10 | 1979-10-10 | $7700.00 | Window Closed / Lapsed |