US3570381A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Programmed electronic shutter
Assignee: Konica Minolta Inc
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Filing: 1968-06-25
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Granted: 1971-03-16
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Expires: 1988-06-25
Abstract
Abstract A control circuit and apparatus for automatically controlling the exposure time and aperture opening of a camera is provided in which a photovoltaic cell is mounted on a camera and connected to a transistor controlled triggering circuit for effecting shutter closure automatically in response to a predetermined amount of light incident on the photovoltaic cell. To automatically control the aperture opening a diaphragm is provided in front of the photovoltaic cell and is linked to the lens diaphragm. Both diaphragms are opened at a predetermined rate upon actuation of the shutter release to provide a continuously varying lens opening, the proper aperture opening being automatically determined by the automatic closure of the shutter by the triggering circuit.
Inventors
- 👤 Arata Satoo
- 👤 Yasuo Uchida
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 19:53
CPC Classifications
G; G03; G03B; G03B7/00; G03B7/08; G03B7/081; G03B7/083
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
172 words
An electronic shutter including a photovoltaic cell and a triggering circuit having a source of power therein, a lens diaphragm for controlling lens aperture and a diaphragm mounted in front of said photovoltaic cell for automatically controlling the F-stop of said camera, said diaphragm being linked to said lens diaphragm such that when the shutter release of the camera is operated, both said diaphragms are moved in their opening direction at predetermined rates, said photovoltaic cell being connected in parallel with a transistor and a capacitor in said triggering circuit to linearly control the charging current to said capacitor as a function of the incident light and the variable diaphragm opening, triggering means in said circuit responsive to a predetermined level of capacitor charge, a normally conducting electromagnet connected to said triggering circuit for holding the shutter release in open position while the capacitor is charging, said triggering means being operated when said predetermined level of capacitor charge is reached to deenergize the said electromagnet to close said shutter and complete exposure.
Claim 2
Dependent Claim
172 words
An electronic shutter including a photovoltaic cell and a triggering circuit having a source of power therein, a lens diaphragm for controlling lens aperture and a diaphragm mounted in front of said photovoltaic cell for automatically controlling the F-stop of said camera, said diaphragm being linked to said lens diaphragm such that when the shutter release of the camera is operated, both said diaphragms are moved in their opening direction at predetermined rates, said photovoltaic cell being connected in parallel with a transistor and a capacitor in said triggering circuit to linearly control the charging current to said capacitor as a function of the incident light and the variable diaphragm opening, triggering means in said circuit responsive to a predetermined level of capacitor charge, a normally conducting electromagnet connected to said triggering circuit for holding the shutter release in open position while the capacitor is charging, said triggering means being operated when said predetermined level of capacitor charge is reached to deenergize the said electromagnet to close said shutter and complete exposure.
Claim 3
Dependent Claim
47 words
An electronic shutter according to claim 1, wherein the diaphragm associated with the photovoltaic cell is shaped so as to provide during the initial phase of the opening of the both diaphragms, a greater amount of exposure to the cell than that provided by the lens diaphragm.
Claim 4
Dependent Claim
58 words
An electronic shutter according to claim 1, further comprising a pair of contacts making the electrical circuit of a flashbulb, the relative position of said contacts being determined by a member interlocked with the focus adjusting means of the camera, thereby causing the flashbulb to fire early or later depending on the distance to an object being photographed.
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) | 1974-03-15 | 1974-09-14 | 1975-03-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-03-15 | 1978-09-14 | 1979-03-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-03-15 | 1982-09-14 | 1983-03-16 | $7700.00 | Window Closed / Lapsed |