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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
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Expires: 1982-12-04
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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 10:35
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

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