US4099190A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Indication device in viewfinder for a single lens reflex camera
Assignee: Nikon Corp
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Filing: 1976-11-15
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Granted: 1978-07-04
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Expires: 1996-11-15
Abstract
Abstract The disclosure describes an indication device in viewfinder for a single lens reflex camera having an exchangeable viewfinder optical system. To improve the exchangeability of the components of the viewfinder optical system, informative members necessary for indicating the information of shutter speed, diaphragm aperture and the like are built in the camera body itself. Among the components of the viewfinder optical system, the condenser lens member and the focusing screen member is enclosed with a frame member to form an unitary viewfinder screen unit. Making use of the space in the unit, a necessary reflective member is fixed to the underside of the condenser lens member. A lighting window is formed on the frame member to direct the information coming from the informative members to the reflective member.
Inventors
- 👤 Tomio Tsuruoka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 08:10
CPC Classifications
G; G03; G03B; G03B17/00; G03B17/18; G03B17/20
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
197 words
A single lens reflex camera comprising: an objective lens for receiving light from the object to be photographed; a view-finder eyepiece for observing an image of the object; a visual field frame provided in the light path from the objective lens to determine a visual field of the view-finder eyepiece. a view-finder optical system for guiding light from the objective lens to the view-finder eyepiece, which system includes a focusing screen member provided in the proximity of the visual field frame so that the image of the object may be formed on the focusing screen member; a condenser lens member having an extended portion out of the light path passing through the visual field frame; and a finder member for guiding light from the condenser lens member to the view-finder eyepiece; frame means for detachably mounting the view-finder eyepiece and the view-finder optical system onto the camera body; information indicating means for indicating exposure information, which means is provided within the camera body; and guide means for guiding the information indicated by the information indicating means to the extended portion of the condenser lens member so that the information may be made observable through the view-finder eyepiece.
Claim 2
Dependent Claim
197 words
A single lens reflex camera comprising: an objective lens for receiving light from the object to be photographed; a view-finder eyepiece for observing an image of the object; a visual field frame provided in the light path from the objective lens to determine a visual field of the view-finder eyepiece. a view-finder optical system for guiding light from the objective lens to the view-finder eyepiece, which system includes a focusing screen member provided in the proximity of the visual field frame so that the image of the object may be formed on the focusing screen member; a condenser lens member having an extended portion out of the light path passing through the visual field frame; and a finder member for guiding light from the condenser lens member to the view-finder eyepiece; frame means for detachably mounting the view-finder eyepiece and the view-finder optical system onto the camera body; information indicating means for indicating exposure information, which means is provided within the camera body; and guide means for guiding the information indicated by the information indicating means to the extended portion of the condenser lens member so that the information may be made observable through the view-finder eyepiece.
Claim 3
Dependent Claim
121 words
A single lens reflex camera according to claim 1, wherein said guide means includes light transmissive means formed on the camera body for leading the exposure information to the exterior of the camera body; lighting window means formed on said frame means for introducing the exposure information led by the light transmissive means; the light transmissive means and the lighting window means being in opposed relation to each other when the view-finder eyepiece and the view-finder optical system are mounted on the camera body; and reflecting means for guiding the exposure information introduced by the lighting window means to the extended portion of the condenser lens member, said reflecting means being detachably mounted to the camera body by said frame means.
Claim 4
Dependent Claim
34 words
A single lens reflex camera according to claim 2, wherein said frame means includes a frame member incorporating integrally therewithin at least the focusing screen member, the condenser lens member and the reflecting means.
Claim 5
Dependent Claim
25 words
A single lens reflex camera according to claim 3, wherein said reflecting means is provided between said focusing screen member and said condenser lens member.
Claim 6
Dependent Claim
36 words
A single lens reflex camera according to claim 2, wherein said information indicating means are provided adjacent to said light transmissive means for indicating said exposure information; and means are provided for illuminating said indicating 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) | 1981-07-03 | 1982-01-02 | 1982-07-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-07-03 | 1986-01-02 | 1986-07-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-07-03 | 1990-01-02 | 1990-07-04 | $7700.00 | Window Closed / Lapsed |