US3631784A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Reflex camera having a prismatic viewfinder and photoelectric exposure meter
Assignee: Pentacon GmbH Foto und Feinwerktechnik
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Filing: 1969-02-14
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Granted: 1972-01-04
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Expires: 1989-02-14
Abstract
Abstract A reflex camera has a prismatic viewfinder, a photoelectric exposure meter and two light guides. The light guides are positioned together on one surface of the viewfinder prism. The first light guide directs light from the viewfinder onto the photoconductive cell of the exposure meter. The second light guide directs light from the direction of the exposure measuring indicator of the exposure meter through the viewfinder.
Inventors
- 👤 Rolf Jurenz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 16:05
CPC Classifications
G; G03; G03B; G03B19/00; G03B19/02; G03B19/12; G03B7/00; G03B7/08; G03B7/099; G03B7/0993; G03B7/0997; G03B7/09971; G03B7/09976
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
104 words
In a reflex camera having a prismatic viewfinder, a photoelectric exposure meter Including a photoconductive cell and a measuring indicator, and a first light guide located adjacent both the photoconductive cell and the viewfinder prism for directing light from the viewfinder prism to illuminate the photoconductive cell, the light guide being formed of one or more parts, the provision of a second light guide associated with the measuring indicator and viewfinder prism and being located adjacent said first light guide facing one surface of said viewfinder prism for directing light rays incident thereupon from the direction of the measuring indicator into the viewfinder prism.
Claim 2
Dependent Claim
104 words
In a reflex camera having a prismatic viewfinder, a photoelectric exposure meter Including a photoconductive cell and a measuring indicator, and a first light guide located adjacent both the photoconductive cell and the viewfinder prism for directing light from the viewfinder prism to illuminate the photoconductive cell, the light guide being formed of one or more parts, the provision of a second light guide associated with the measuring indicator and viewfinder prism and being located adjacent said first light guide facing one surface of said viewfinder prism for directing light rays incident thereupon from the direction of the measuring indicator into the viewfinder prism.
Claim 3
Dependent Claim
65 words
A reflex camera according to claim 1, wherein the one surface of the viewfinder prism is a partly reflective mirror-coated surface and wherein the light entry surface of the first light conductor is positioned behind the partly reflective mirror-coated zone of the said one surface, the light emission surface of the second light guide being positioned behind a nonmirror-coated zone of the said one surface.
Claim 4
Dependent Claim
24 words
A reflex camera according to claim 2, wherein the two light guides form a constructional assembly affixed to the surface of the prism viewfinder.
Claim 5
Dependent Claim
23 words
A reflex camera according to claim 3, wherein the surface on which the light guides are mounted is the surface of a pentaprism.
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) | 1975-01-03 | 1975-07-05 | 1976-01-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-03 | 1979-07-05 | 1980-01-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-03 | 1983-07-05 | 1984-01-04 | $7700.00 | Window Closed / Lapsed |