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US2673489A Expired / Lapsed US ⏱️ 0.0 years remaining

Incandescent light source and condensing system for optical projectors

Assignee: American Optical Corp
•
Filing: 1950-09-21
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Granted: 1954-03-30
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Expires: 1970-09-21
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Abstract

No abstract record available.

Inventors

  • 👤 David I Critoph
  • 👤 Albin A Gradisar

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 09:10
CPC Classifications
G; G03; G03B; G03B21/00; G03B21/14; G03B21/20; G03B21/208

Claims Analysis

Total Claims: 0
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References Cited (Backward Citations)

US1313857A Cited
US1213975A Cited
US1213974A Cited
US1239371A Cited
US1709017A Cited
US1991861A Cited
US1962356A Cited
US2485377A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1957-03-29 1957-09-28 1958-03-30 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1961-03-29 1961-09-28 1962-03-30 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1965-03-29 1965-09-28 1966-03-30 $7700.00 Window Closed / Lapsed

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