US4081805A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for displaying the amount of exposure in a single lens reflex camera using an electronic shutter
Assignee: Ricoh Co Ltd
•
Filing: 1976-06-15
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Granted: 1978-03-28
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Expires: 1996-06-15
Abstract
Abstract An apparatus for displaying the amount of exposure in a single lens reflex camera using an electronic shutter in which the shutter speed can be established either automatically or manually and can be displayed in a digital manner. When the shutter speed is manually established, the apparatus indicates an underexposure or overexposure, beyond a selected range, and also displays the amount by which the established value deviates outside the range.
Inventors
- 👤 Akira Takahashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 19:14
CPC Classifications
G; G03; G03B; G03B19/00; G03B19/02; G03B19/12; G03B17/00; G03B17/18; G03B17/20; G03B7/00; G03B7/08; G03B7/091; G03B7/093
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
143 words
A camera of the type having an electronic shutter, said camera comprising: means for automatically setting an exposure time and producing a first output signal in accordance with the magnitude thereof; means for manually setting an exposure time and producing a second output signal in accordance with the magnitude thereof; means for respectively receiving one of said first and second output signals and operating said electronic shutter in accordance with the magnitude of the received signal; means for respectively conducting one of said first and second output signals to said receiving means; first means responsive to said receivng means for indicating an exposure time corresponding to the received signal in said receiving means; means for comparing the magnitude of said first and second output signals and producing a comparative result; and second means responsive to said comparing means for indicating the comparative result.
Claim 2
Dependent Claim
143 words
A camera of the type having an electronic shutter, said camera comprising: means for automatically setting an exposure time and producing a first output signal in accordance with the magnitude thereof; means for manually setting an exposure time and producing a second output signal in accordance with the magnitude thereof; means for respectively receiving one of said first and second output signals and operating said electronic shutter in accordance with the magnitude of the received signal; means for respectively conducting one of said first and second output signals to said receiving means; first means responsive to said receivng means for indicating an exposure time corresponding to the received signal in said receiving means; means for comparing the magnitude of said first and second output signals and producing a comparative result; and second means responsive to said comparing means for indicating the comparative result.
Claim 3
Dependent Claim
50 words
A camera according to claim 1 wherein said second indicating means comprises means for sensing the comparative result in its magnitude and producing an indicative signal in one of three ranges and means for displaying the comparative result in one of three displaying modes corresponding to said three ranges respectively.
Claim 4
Dependent Claim
14 words
A camera according to claim 2 wherein said sensing means comprises a Schmitt circuit.
Claim 5
Dependent Claim
73 words
A camera according to claim 2 wherein said second indicating means further comprises means for dividing the comparative result, when said indicative signal falls within the middle one of said three ranges in its magnitude, into one of a plurality of steps, the middle one of which corresponds to zero and further means for displaying the comparative result in one of a plurality of displaying modes corresponding to said plurality of steps respectively.
Claim 6
Dependent Claim
43 words
A camera according to claim 1 wherein said second indicating means comprises light-emitting means for displaying the comparative result and means for causing light from said light-emitting means to be interrupted at a frequency in accordance with the magnitude of the comparative result.
Claim 7
Dependent Claim
27 words
A camera according to claim 1 wherein said comparing means comprises means for momentarily storing one of said first and second output signals prior to their comparison.
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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) | 1981-03-27 | 1981-09-26 | 1982-03-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-03-27 | 1985-09-26 | 1986-03-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-03-27 | 1989-09-26 | 1990-03-28 | $7700.00 | Window Closed / Lapsed |