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US3121798A Expired / Lapsed US ⏱️ 0.0 years remaining

Variable diaphragm structure for photoelectric exposure meters

Assignee: Zeiss Ikon AG
•
Filing: 1961-01-23
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Granted: 1964-02-18
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Expires: 1981-01-23
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Abstract

No abstract record available.

Inventors

  • 👤 Ploke Martin

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 04:37
CPC Classifications
G; G03; G03B; G03B9/00; G03B9/08; G01; G01J; G01J1/00; G01J1/42; G01J1/4209; G01J1/4214; G02; G02B; G02B5/00; G02B5/005; G03B7/00; G03B7/08; G03B7/099; G03B7/0993

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 132 words
A PHOTOELECTRIC EXPOSURE METER COMPRISING A PHOTOELECTRIC RECEIVER AND TWO VENETIAN BLIND STRUCTURES ARRANGED CONSECUTIVELY AND IN FRONT OF SAID PHOTOELECTRIC RECEIVER FOR VARYING THE AMOUNT OF LIGHT REACHING SAID RECEIVER, EACH OF SAID VENETIAN BLIND STRUCTURES INCLUDING A FRAME AND PARALLEL EXTENDING LOUVER SLATS PIVOTALLY SUPPORTED IN SAID FRAME, SAID VENETIAN BLIND STRUCTURES BEING ARRANGED WITH THEIR SLATS IN CRISS-CROSS INTERSECTING RELATION WITH THE SLATS OF ONE STRUCTURE MOUNTED IN BACK OF THE SLATS OF THE OTHER VENITIAN BLIND STRUCTURE, AND MEANS FOR ROTATABLY ADJUSTING IN EACH ONE OF SAID VENETIAN BLIND STRUCTURES ALL OF SAID SLATS THEREIN AT THE SAME TIME IN SUCH A MANNER THAT ADJACENT SLATS ARE ROTATABLY ADJUSTED IN OPPOSITE DIRECTIONS, AND THE WIDTH OF THE SLOTS FORMED BETWEEN SAID SLATS IS PROGRESSIVELY VARIED, THE PIVOT AXES
Claim 2
Dependent Claim 132 words
A PHOTOELECTRIC EXPOSURE METER COMPRISING A PHOTOELECTRIC RECEIVER AND TWO VENETIAN BLIND STRUCTURES ARRANGED CONSECUTIVELY AND IN FRONT OF SAID PHOTOELECTRIC RECEIVER FOR VARYING THE AMOUNT OF LIGHT REACHING SAID RECEIVER, EACH OF SAID VENETIAN BLIND STRUCTURES INCLUDING A FRAME AND PARALLEL EXTENDING LOUVER SLATS PIVOTALLY SUPPORTED IN SAID FRAME, SAID VENETIAN BLIND STRUCTURES BEING ARRANGED WITH THEIR SLATS IN CRISS-CROSS INTERSECTING RELATION WITH THE SLATS OF ONE STRUCTURE MOUNTED IN BACK OF THE SLATS OF THE OTHER VENITIAN BLIND STRUCTURE, AND MEANS FOR ROTATABLY ADJUSTING IN EACH ONE OF SAID VENETIAN BLIND STRUCTURES ALL OF SAID SLATS THEREIN AT THE SAME TIME IN SUCH A MANNER THAT ADJACENT SLATS ARE ROTATABLY ADJUSTED IN OPPOSITE DIRECTIONS, AND THE WIDTH OF THE SLOTS FORMED BETWEEN SAID SLATS IS PROGRESSIVELY VARIED, THE PIVOT AXES

References Cited (Backward Citations)

US1972492A Cited
US2274441A Cited
US2941080A Cited
US2896508A Cited
US3049962A Cited
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GB847440A Cited
US3045124A Cited
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US3060832A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1967-02-17 1967-08-19 1968-02-18 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1971-02-17 1971-08-19 1972-02-18 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1975-02-17 1975-08-19 1976-02-18 $7700.00 Window Closed / Lapsed

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