Patent US2611498A successfully refreshed from Google Patents.
Patent US3611895A successfully refreshed from Google Patents.
US3611895A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Photographic camera for use in daylight and artificial light
Assignee: Agfa Gevaert AG
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Filing: 1969-10-28
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Granted: 1971-10-12
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Expires: 1989-10-28
Abstract
Abstract A photographic camera wherein the aperture size is a function of scene brightness and of the position of focusing means when the exposure is made in artificial light. Changes in the position of the focusing means effect changes in sensitivity of the circuit which includes a photosensitive receiver and directly controls the diaphragm. The sensitivity of the circuit is changed by changing the resistance of a variable resistor which is connectable in parallel with the receiver or by changing the amount of scene light which reaches the receiver in response to changes in the position of the focusing means.
Inventors
- 👤 Joachim Von Albedyll
- 👤 Hans-Peter Huber
- 👤 Karl Wagner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:06
CPC Classifications
G; G03; G03B; G03B9/00; G03B9/70; G03B7/00; G03B7/08; G03B7/081; G03B7/085; G03B7/16
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
133 words
In a photographic camera for use in daylight and artificial light, an exposure control comprising focusing means movable between a plurality of positions each indicative of a different distance from the subject; an electric circuit including photosensitive receiver means exposed to scene light and arranged to change its condition in dependency on the intensity and amounts of such Light; adjustable exposure value determining means arranged to determine exposure values as a function of the condition of said receiver means; and adjusting means for regulating the condition of said receiver means as a function of the position of said focusing means when the camera is used to make exposures in artificial light, said adjusting means comprising masking means movable by said focusing means to thereby vary the amounts of light reaching said receiver means.
Claim 2
Dependent Claim
133 words
In a photographic camera for use in daylight and artificial light, an exposure control comprising focusing means movable between a plurality of positions each indicative of a different distance from the subject; an electric circuit including photosensitive receiver means exposed to scene light and arranged to change its condition in dependency on the intensity and amounts of such Light; adjustable exposure value determining means arranged to determine exposure values as a function of the condition of said receiver means; and adjusting means for regulating the condition of said receiver means as a function of the position of said focusing means when the camera is used to make exposures in artificial light, said adjusting means comprising masking means movable by said focusing means to thereby vary the amounts of light reaching said receiver means.
Claim 3
Dependent Claim
31 words
An exposure control as defined in claim 1, wherein said masking means consists of opaque material and has a tapering light-admitting notch which is movable with reference to said receiver means.
Claim 4
Dependent Claim
62 words
An exposure control as defined in claim 1, wherein said circuit further includes capacitor means in series with said receiver means and an energy source in series with said receiver means, and further comprising release means movable between first and second positions and switch means for respectively opening and completing said circuit in the first and second positions of said release means.
Claim 5
Dependent Claim
60 words
An exposure control as defined in claim 1, wherein said exposure value determining means includes diaphragm means and wherein said circuit further comprises electromagnet means energizable upon completion of said circuit with a delay which is a function of scene brightness and of the position of said masking means to thereby determine the aperture size defined by said diaphragm means.
Claim 6
Dependent Claim
64 words
An exposure control as defined in claim 4, wherein said circuit further comprises capacitor means chargeable at a rate which is a function of the condition of said receiver means and of the position of said masking means and transistor means arranged to conduct current and to thereby effect energization of said electromagnet means when said capacitor means is charged to a predetermined extent.
Claim 7
Dependent Claim
16 words
An exposure control as defined in claim 1, wherein said receiver means comprises a photosensitive resistor.
Claim 8
Dependent Claim
16 words
An exposure control as defined in claim 1, wherein said focusing means is movable by hand.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-10-11 | 1975-04-12 | 1975-10-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-10-11 | 1979-04-12 | 1979-10-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-10-11 | 1983-04-12 | 1983-10-12 | $7700.00 | Window Closed / Lapsed |