Patent US3611892A successfully refreshed from Google Patents.
US3611892A
Expired / Lapsed
US
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Device for indicating underexposure in photographic cameras with automatic exposure control
Assignee: Eastman Kodak Co
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Filing: 1968-10-29
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Granted: 1971-10-12
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Expires: 1988-10-29
Abstract
Abstract In a camera of the type having a movable exposure control member for varying an exposure parameter from a maximum to a minimum, and a photoelectric circuit that controls a transducer for selectively stopping the movement of the exposure control member to establish the exposure parameter in accordance with the level of scene illumination, a low-light indicator is provided including means associated with a movable shutter-release member for moving the exposure control member from its maximum exposure parameter position to its minimum exposure parameter position, and an electric signal means coupled with the photoelectric circuit for actuation immediately upon movement of the release member, when the scene illumination is below a predetermined level.
Inventors
- 👤 Wolfgang Ort
- 👤 Michael Reich
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 22:47
CPC Classifications
G; G03; G03B; G03B7/00; G03B7/08; G03B7/081; G03B7/085
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
227 words
In a camera having diaphragm means for establishing an exposure aperture including a member movable along a path to vary the size of the exposure aperture from a maximum size to a minimum size, and having an actuatable electromechanical transducer for selectively stopping the movement of the diaphragm member along its path to establish the exposure aperture size, a low-light indicator comprising: a. actuatable drive means for moving the diaphragm member from its maximum aperture position to its minimum aperture position; b. photoresponsive means adapted to receive illumination from an object scene and having an electric parameter which varies as a function of the level of scene illumination incident thereon; c. electric circuit means operatively connected to said photoresponsive means and to the transducer for controlling actuation of the transducer in accordance with said electric parameter to establish an exposure aperture size in accordance with the level of scene illumination incident on said photoresponsive means; d. means movable for variably attenuating the scene illumination incident on said photoresponsive means; e. means coupling said attenuating means with said diaphragm member for simultaneous movement therewith; f. electrically actuatable signal means connected to said circuit means and to said photoresponsive means; and g. means for actuating said signal means in response to actuation of said drive means, when the illumination incident on said photoresponsive means is below a predetermined level.
Claim 2
Dependent Claim
227 words
In a camera having diaphragm means for establishing an exposure aperture including a member movable along a path to vary the size of the exposure aperture from a maximum size to a minimum size, and having an actuatable electromechanical transducer for selectively stopping the movement of the diaphragm member along its path to establish the exposure aperture size, a low-light indicator comprising: a. actuatable drive means for moving the diaphragm member from its maximum aperture position to its minimum aperture position; b. photoresponsive means adapted to receive illumination from an object scene and having an electric parameter which varies as a function of the level of scene illumination incident thereon; c. electric circuit means operatively connected to said photoresponsive means and to the transducer for controlling actuation of the transducer in accordance with said electric parameter to establish an exposure aperture size in accordance with the level of scene illumination incident on said photoresponsive means; d. means movable for variably attenuating the scene illumination incident on said photoresponsive means; e. means coupling said attenuating means with said diaphragm member for simultaneous movement therewith; f. electrically actuatable signal means connected to said circuit means and to said photoresponsive means; and g. means for actuating said signal means in response to actuation of said drive means, when the illumination incident on said photoresponsive means is below a predetermined level.
Claim 3
Dependent Claim
194 words
In an automatic exposure control apparatus having an exposure control member movable along a path to vary an exposure parameter from a maximum to a minimum, and having an actuatable electromechanical transducer for selectively stopping the movement of said member along its path to establish the exposure parameter, a light-low indicator comprising; a. actuatable drive means for moving said exposure control member from its maximum exposure parameter position to its minimum exposure parameter position; b. a photoelectric cell adapted to be exposed to scene illumination; c. means movable for variably attenuating the scene illumination incident on said photocell; d. means coupling said attenuating means with said exposure control member for substantially simultaneous movement therewith; e. electric circuit means coupled to said photoelectric cell and to said transducer for actuating said transducer to stop the movement of the control member when the illumination of said photocell is attenuated to a predetermined level; f. electrically actuatable signal means coupled to said circuit means and to saiD photoelectric cell, and g. means for actuating said signal means in response to actuation of said drive means, when the illumination incident on said photocell is below said predetermined level.
Claim 4
Dependent Claim
194 words
In an automatic exposure control apparatus having an exposure control member movable along a path to vary an exposure parameter from a maximum to a minimum, and having an actuatable electromechanical transducer for selectively stopping the movement of said member along its path to establish the exposure parameter, a light-low indicator comprising; a. actuatable drive means for moving said exposure control member from its maximum exposure parameter position to its minimum exposure parameter position; b. a photoelectric cell adapted to be exposed to scene illumination; c. means movable for variably attenuating the scene illumination incident on said photocell; d. means coupling said attenuating means with said exposure control member for substantially simultaneous movement therewith; e. electric circuit means coupled to said photoelectric cell and to said transducer for actuating said transducer to stop the movement of the control member when the illumination of said photocell is attenuated to a predetermined level; f. electrically actuatable signal means coupled to said circuit means and to saiD photoelectric cell, and g. means for actuating said signal means in response to actuation of said drive means, when the illumination incident on said photocell is below said predetermined level.
Claim 5
Dependent Claim
116 words
A low scene-light indicator for a photographic camera comprising: a. electrically actuatable signal means; b. first and second switch means electrically connected in series with said signal means for controlling actuation thereof; c. actuatable means for initiating an exposure interval, said exposure-initiating means being associated with said first switch means for holding said first switch means normally open, and for closing said first switch means upon actuation to initiate an exposure interval; and d. an exposure control member movable to vary an exposure parameter, said member being associated with said second switch means for holding said second switch means normally closed and for opening said second switch in response to movement of said exposure control member.
Claim 6
Dependent Claim
116 words
A low scene-light indicator for a photographic camera comprising: a. electrically actuatable signal means; b. first and second switch means electrically connected in series with said signal means for controlling actuation thereof; c. actuatable means for initiating an exposure interval, said exposure-initiating means being associated with said first switch means for holding said first switch means normally open, and for closing said first switch means upon actuation to initiate an exposure interval; and d. an exposure control member movable to vary an exposure parameter, said member being associated with said second switch means for holding said second switch means normally closed and for opening said second switch in response to movement of said exposure control member.
Claim 7
Dependent Claim
13 words
An indicator as in claim 3 wherein said signal means is a lamp.
Claim 8
Dependent Claim
123 words
In a photographic camera a low-light level indicator for indicating when scene illumination is below a predetermined level, said indicator comprising: a. an exposure control member movable along a path to vary an exposure parameter from a maximum to a minimum; b. an exposure release member movable from a rest position to a release position to initiate operation of the camera; c. means responsive to movement of said release member from its rest position to its release position for moving said control member from its maximum exposure parameter position to its minimum exposure position; and d. signal means actuatable in response to initial movement of said release member from its rest position for indicating if the light level is below the predetermined value.
Claim 9
Dependent Claim
123 words
In a photographic camera a low-light level indicator for indicating when scene illumination is below a predetermined level, said indicator comprising: a. an exposure control member movable along a path to vary an exposure parameter from a maximum to a minimum; b. an exposure release member movable from a rest position to a release position to initiate operation of the camera; c. means responsive to movement of said release member from its rest position to its release position for moving said control member from its maximum exposure parameter position to its minimum exposure position; and d. signal means actuatable in response to initial movement of said release member from its rest position for indicating if the light level is below the predetermined value.
References Cited (Backward Citations)
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 |