Patent US3667357A successfully refreshed from Google Patents.
US3667357A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Automatic control devices for a camera
Assignee: Minolta Co Ltd
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Filing: 1969-12-12
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Granted: 1972-06-06
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Expires: 1989-12-12
Abstract
Abstract An automatic exposure control device for a camera is actuated by outputs from two separate delay circuits. The first delay circuit includes means for storing an electrical signal in accordance with the brightness of an object to provide a first output, and the second delay circuit includes means for storing an electrical signal representative of a desired flash time delay to provide a second output. A switching circuit is responsive to the first and second outputs whereby a flash circuit is actuated only when the second output exceeds the first output. A modified embodiment incorporates a third delay circuit and the flash is actuated only when the first output is less than the third output or when the first output exceeds the third output which in turn exceeds the second output. The first and second delay circuits are respectively responsive to the brightness of the entire picture and a central portion of the picture, whereas the third delay circuit provides the desired flash time delay.
Inventors
- 👤 Motonobu Matsuda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 05:09
CPC Classifications
G; G03; G03B; G03B9/00; G03B9/70; G03B7/00; G03B7/08; G03B7/081; G03B7/083
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
163 words
An automatic exposure control device for a camera having a shutter mechanism, comprising: a first delay circuit for providing a first output including means responsive to the object brightness and a first device for storing an electrical signal in accordance with the response of said responsive means; a second delay circuit for providing a second output including means for varying the delay of said circuit in accordance with a desired flash control time and a second device for storing an electrical signal representing said delay; an electric power source for energizing said first and second delay circuits; a switching circuit for controlling the timing of said shutter mechanism and including first and second inputs respectively connected to receive said first and second outputs; and a flash firing circuit including flash means and switch means for actuating said flash means, said switch means are responsive to said first and second outputs to actuate said flash means when said second output exceeds said first output.
Claim 2
Dependent Claim
163 words
An automatic exposure control device for a camera having a shutter mechanism, comprising: a first delay circuit for providing a first output including means responsive to the object brightness and a first device for storing an electrical signal in accordance with the response of said responsive means; a second delay circuit for providing a second output including means for varying the delay of said circuit in accordance with a desired flash control time and a second device for storing an electrical signal representing said delay; an electric power source for energizing said first and second delay circuits; a switching circuit for controlling the timing of said shutter mechanism and including first and second inputs respectively connected to receive said first and second outputs; and a flash firing circuit including flash means and switch means for actuating said flash means, said switch means are responsive to said first and second outputs to actuate said flash means when said second output exceeds said first output.
Claim 3
Dependent Claim
38 words
A device as in claim 1 further comprising an indicating circuit actuated by said second output exceeding said first output, and said switch means is responsive to the actuation of said indicating circuit to actuate said flash means.
Claim 4
Dependent Claim
64 words
A device as in claim 2 wherein said indicating circuit includes an indicating lamp and a silicon controlled rectifier for actuating said lamp and including a gate connected to said first output and a cathode connected to said second output, and said switch means includes a control terminal connected to said indicating lamp whereby lighting of said lamp effects actuation of said switch means.
Claim 5
Dependent Claim
20 words
A device as in claim 1 further comprising an indicating circuit actuated by said second output exceeding said first output.
Claim 6
Dependent Claim
223 words
An automatic exposure control device for a camera having a shutter mechanism, comprising: a first delay circuit for providing a first output and including first means responsive to the over-all brightness of the object and a first device for storing an electrical signal in accordance with the response of said first means; a second delay circuit for providing a second output and including second means responsive to the brightness from a selected portion of said object and second means for storing an electrical signal in accordance with the response of said second means; a third delay circuit including means for varying the delay of said circuit and third means for storing an electrical signal representing said delay; an electric power source for energizing said first, second and third delay circuits; a switching circuit responsive to said first and third outputs for actuating said shutter mechanism; a flash firing circuit including flash means and first switch means for actuating said flash means; said first switch means is responsive to said first and third outputs when said first output is less than said third output to actuate said flash means, and said first switch means is responsive to said first, second and third outputs to actuate said flash means when said first output exceeds said third output and said third output exceeds said second output.
Claim 7
Dependent Claim
223 words
An automatic exposure control device for a camera having a shutter mechanism, comprising: a first delay circuit for providing a first output and including first means responsive to the over-all brightness of the object and a first device for storing an electrical signal in accordance with the response of said first means; a second delay circuit for providing a second output and including second means responsive to the brightness from a selected portion of said object and second means for storing an electrical signal in accordance with the response of said second means; a third delay circuit including means for varying the delay of said circuit and third means for storing an electrical signal representing said delay; an electric power source for energizing said first, second and third delay circuits; a switching circuit responsive to said first and third outputs for actuating said shutter mechanism; a flash firing circuit including flash means and first switch means for actuating said flash means; said first switch means is responsive to said first and third outputs when said first output is less than said third output to actuate said flash means, and said first switch means is responsive to said first, second and third outputs to actuate said flash means when said first output exceeds said third output and said third output exceeds said second output.
Claim 8
Dependent Claim
152 words
An automatic exposure control device for a camera having a shutter mechanism, comprising: a first delay circuit for providing a first output and including first means responsive to the over-all brightness of the object and a first device for storing an electrical signal in accordance with the response of said first means; a second delay circuit for providing a second output and including second means responsive to the brightness from a selected portion of said object and second means for storing an electrical signal in accordance with the response Of said second means; an electric power source for energizing said first and second delay circuits; a switching circuit responsive to said first output for actuating said shutter mechanism; a flash firing circuit including flash means and switch means for actuating said flash means; and said switch means is responsive to said first output exceeding said second output to actuate said flash means.
Claim 9
Dependent Claim
152 words
An automatic exposure control device for a camera having a shutter mechanism, comprising: a first delay circuit for providing a first output and including first means responsive to the over-all brightness of the object and a first device for storing an electrical signal in accordance with the response of said first means; a second delay circuit for providing a second output and including second means responsive to the brightness from a selected portion of said object and second means for storing an electrical signal in accordance with the response Of said second means; an electric power source for energizing said first and second delay circuits; a switching circuit responsive to said first output for actuating said shutter mechanism; a flash firing circuit including flash means and switch means for actuating said flash means; and said switch means is responsive to said first output exceeding said second output to actuate said flash means.
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) | 1975-06-06 | 1975-12-06 | 1976-06-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-06 | 1979-12-06 | 1980-06-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-06 | 1983-12-06 | 1984-06-06 | $7700.00 | Window Closed / Lapsed |