Patent US3872483A successfully refreshed from Google Patents.
US3872483A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Device for indicating digital exposure information in the viewfinder of a camera
Assignee: Fujinon Corp
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Filing: 1974-07-29
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Granted: 1975-03-18
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Expires: 1994-07-29
Abstract
Abstract Analogue information from an exposure meter indicative of an exposure factor is converted to digital information by an A-D converter. The sampling period of A-D conversion of the A-D converter is set to be equal to or longer than 0.2 second. The digital information is indicated by a digital indicator in the viewfinder of the camera. The sampling period is preferably shorter than one second.
Inventors
- 👤 Saburo Numata
- 👤 Iwao Sagara
- 👤 Hirohisa Shishikura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 08:36
CPC Classifications
G; G03; G03B; G03B17/00; G03B17/18; G03B17/20
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
178 words
A device for indicating digital exposure information in the viewfinder of a camera comprising an exposure measuring means including a photodetector to receive light from the object to be photographed and generating an analogue output corresponding to the amount of light received by the photodetector, an A-D converter connected with the exposure measuring means for converting said analogue output to a digital output, a sampling pulse generating means connected with the A-D converter for giving sampling pulses to the A-D converter to determine the sampling intervals of A-D conversion of the A-D converter, a digital information indicating means including light emitting segments arranged in the shape of numerals for indicating exposure information in a digital form, and a control circuit connected with said A-D converter, said sampling pulse generating means and said digital information indicating means for converting the digital output from the A-D converter to a signal for selectively energizing said light emitting segments to indicate the digital output in a digital form, the period of said sampling pulses being equal to or longer than 0.2 second.
Claim 2
Independent Claim
178 words
A device for indicating digital exposure information in the viewfinder of a camera comprising an exposure measuring means including a photodetector to receive light from the object to be photographed and generating an analogue output corresponding to the amount of light received by the photodetector, an A-D converter connected with the exposure measuring means for converting said analogue output to a digital output, a sampling pulse generating means connected with the A-D converter for giving sampling pulses to the A-D converter to determine the sampling intervals of A-D conversion of the A-D converter, a digital information indicating means including light emitting segments arranged in the shape of numerals for indicating exposure information in a digital form, and a control circuit connected with said A-D converter, said sampling pulse generating means and said digital information indicating means for converting the digital output from the A-D converter to a signal for selectively energizing said light emitting segments to indicate the digital output in a digital form, the period of said sampling pulses being equal to or longer than 0.2 second.
Claim 3
Dependent Claim
33 words
A device for indicating digital exposure information in the viewfinder of a camera as defined in claim 1 wherein said period of the sampling pulses is equal to or shorter than 1.0 second.
Claim 4
Dependent Claim
72 words
A device for indicating digital exposure information in the viewfinder of a camera as defined in claim 1 wherein said exposure measuring means includes a diaphragm hole size input means associated with a diaphragm operating means in the camera and generates an analogue output which corresponds to the shutter speed desired to obtain a correct exposure, and said digital information indicating means indicates the exposure information in terms of a shutter speed.
Claim 5
Dependent Claim
74 words
A device for indicating digital exposure information in the viewfinder of a camera as defined in claim 1 wherein said exposure measuring means includes a shutter speed input means associated with a shutter speed setting means in the camera and generates an analogue output which corresponds to the diaphragm hole size desired to obtain a correct exposure, and said digital information indicating means indicates the exposure information in terms of a diaphragm hole size.
Claim 6
Dependent Claim
199 words
In a photographic camera including an automatic exposure control means in which the shutter speed is automatically controlled in accordance with the output of an exposure measuring means which includes a photodetector and a diaphragm hole size input means, a device for indicating the automatically controlled shutter speed in the viewfinder of the camera comprising: an A-D converter connected with said exposure measuring means for converting an analogue output from the exposure measuring means to a digital output indicative of a shutter speed desirable to obtain a correct exposure, a sampling pulse generating means connected with the A-D converter for giving sampling pulses to the A-D converter to determine the sampling intervals of A-D conversion thereof, the period of said sampling pulses being 0.2 to 1.0 second, a digital information indicating means including light emitting segments arranged in the shape of numerals for indicating a shutter speed in a digital form, and a control circuit connected with said A-D converter, said sampling pulse generating means and said digital information indicating means for converting the digital output from the A-D converter to a signal for selectively energizing said light emitting segments to indicate the shutter speed in a digital form.
Claim 7
Dependent Claim
199 words
In a photographic camera including an automatic exposure control means in which the shutter speed is automatically controlled in accordance with the output of an exposure measuring means which includes a photodetector and a diaphragm hole size input means, a device for indicating the automatically controlled shutter speed in the viewfinder of the camera comprising: an A-D converter connected with said exposure measuring means for converting an analogue output from the exposure measuring means to a digital output indicative of a shutter speed desirable to obtain a correct exposure, a sampling pulse generating means connected with the A-D converter for giving sampling pulses to the A-D converter to determine the sampling intervals of A-D conversion thereof, the period of said sampling pulses being 0.2 to 1.0 second, a digital information indicating means including light emitting segments arranged in the shape of numerals for indicating a shutter speed in a digital form, and a control circuit connected with said A-D converter, said sampling pulse generating means and said digital information indicating means for converting the digital output from the A-D converter to a signal for selectively energizing said light emitting segments to indicate the shutter speed in a digital form.
References Cited (Backward Citations)
US3727527A
Cited
US3818495A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-03-17 | 1978-09-16 | 1979-03-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-17 | 1982-09-16 | 1983-03-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-17 | 1986-09-16 | 1987-03-18 | $7700.00 | Window Closed / Lapsed |