US3903530A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Camera having a finder illumination device
Assignee: Canon Inc
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Filing: 1974-04-01
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Granted: 1975-09-02
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Expires: 1994-04-01
Abstract
Abstract In a camera having such an information indication member as a scale plate, a pointer, etc. to indicate photographing informations such as a diaphragm aperture value, a shutter value, etc., and other conditions of the camera within a finder, and an illumination device for enabling said informations to be seen in a dark place. A finder illumination device is provided to clamp the indication member of an exposure meter as the inside of the finder is illuminated for preventing the exposure meter from making erroneous indication when the illuminating light is made incident into the light receiving element of the exposure meter positioned near the finder optical path.
Inventors
- 👤 Tatsuya Taguchi
- 👤 Nobuaki Date
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 21:02
CPC Classifications
G; G03; G03B; G03B19/00; G03B19/02; G03B19/12
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
135 words
In a camera having a finder illumination device, a shutter and a shutter release member, comprising: an exposure meter having a light receiving element provided adjacent to a finder optical path and a movable member which is shifted in response to the amount of light received by said light receiving element; a photographic information indicating element positioned within said finder optical path; an illumination circuit including means to illuminate said indicating element, a power source and a first switch; means for clamping said movable member of said exposure meter, said clamping means cooperating with said switch of said illumination circuit so as to close said switch when said movable member is clamped; and a second switch cooperating witH said shutter release member for opening the illumination circuit during the opening and closing of said shutter.
Claim 2
Dependent Claim
135 words
In a camera having a finder illumination device, a shutter and a shutter release member, comprising: an exposure meter having a light receiving element provided adjacent to a finder optical path and a movable member which is shifted in response to the amount of light received by said light receiving element; a photographic information indicating element positioned within said finder optical path; an illumination circuit including means to illuminate said indicating element, a power source and a first switch; means for clamping said movable member of said exposure meter, said clamping means cooperating with said switch of said illumination circuit so as to close said switch when said movable member is clamped; and a second switch cooperating witH said shutter release member for opening the illumination circuit during the opening and closing of said shutter.
Claim 3
Dependent Claim
27 words
The camera of claim 1 wherein said second switch is normally closed so as to allow actuation of said illuminating means when said clamping means is operated.
Claim 4
Dependent Claim
43 words
The camera of claim 2 wherein said second switch is held in said normally closed position by a switch operating member in cooperation with a locking member, said locking member releasing said switch operating member by the action of said shutter release member.
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) | 1978-09-01 | 1979-03-03 | 1979-09-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-01 | 1983-03-03 | 1983-09-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-01 | 1987-03-03 | 1987-09-02 | $7700.00 | Window Closed / Lapsed |