Patent US3956759A successfully refreshed from Google Patents.
US3956759A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Compact single lens reflex cassette camera
Assignee: Pentax Corp
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Filing: 1974-08-15
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Granted: 1976-05-11
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Expires: 1994-08-15
Abstract
Abstract A cassette type single lens reflex camera includes a longitudinally extending zoon lens system and a replacable film cassette disposed in opposite sides of the camera casing, the cassette having enlarged film storing opposite end sections joined by a tubular film guide with an inwardly vertically facing framing window. A 45° semitransparent first mirror intercepts the zoom lens longitudinal optical axis to reflect lens traversing light through a rear lens group onto a second 45° mirror mounted in the casing in the space between the cassette end sections and oriented to deflect the light from the first mirror to the cassette window. The light traversing the first mirror traverses, successively imaging and field lenses an erecting prism and an eyepiece lens which define a viewfinder.
Inventors
- 👤 Tohru Karikawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 22:45
CPC Classifications
G; G03; G03B; G03B19/00; G03B19/02; G03B19/12; G03B17/00; G03B17/02; G03B17/12; G03B17/14
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
211 words
The combination of a cassette type camera and a film carrying cassette comprising a casing having a longitudinally extending Z-axis, a film cassette replaceably housed in said casing and extending longitudinally thereof and including at longitudinally spaced opposite ends thereof enlarged film storing sections connected by a film guide section, guiding film between said storing sections in a longitudinal direction parallel to said Z-axis and having a frame delineating window facing inwardly in a direction parallel to the Y-axis, an objective lens system located in said casing and spaced a distance the X-axis from said cassette and having an elongated forward portion, said forward portion of said objective lens system extending along a first optical axis parallel to the Z-axis, a first reflector intercepting said first optical axis and oriented to deflect rays traversing said forward portion of said optical lens system along said first optical axis, along a second optical axis parallel to the X-axis toward the space between said cassette end sections, and a second reflector mounted in said casing between said cassette end sections and oriented to deflect the rays deflected by said first reflector thereto along a third optical axis parallel to the Y-axis to said cassette window, said X, Y and Z axes being mutually perpendicular.
Claim 2
Dependent Claim
211 words
The combination of a cassette type camera and a film carrying cassette comprising a casing having a longitudinally extending Z-axis, a film cassette replaceably housed in said casing and extending longitudinally thereof and including at longitudinally spaced opposite ends thereof enlarged film storing sections connected by a film guide section, guiding film between said storing sections in a longitudinal direction parallel to said Z-axis and having a frame delineating window facing inwardly in a direction parallel to the Y-axis, an objective lens system located in said casing and spaced a distance the X-axis from said cassette and having an elongated forward portion, said forward portion of said objective lens system extending along a first optical axis parallel to the Z-axis, a first reflector intercepting said first optical axis and oriented to deflect rays traversing said forward portion of said optical lens system along said first optical axis, along a second optical axis parallel to the X-axis toward the space between said cassette end sections, and a second reflector mounted in said casing between said cassette end sections and oriented to deflect the rays deflected by said first reflector thereto along a third optical axis parallel to the Y-axis to said cassette window, said X, Y and Z axes being mutually perpendicular.
Claim 3
Dependent Claim
14 words
The combination of claim 1 wherein said lens system comprises a zoom lens system.
Claim 4
Dependent Claim
24 words
The combination of claim 2 wherein said lens system includes a lens group along said second optical axis between said first and second reflectors.
Claim 5
Dependent Claim
44 words
The combination of claim 1 wherein said first reflector comprises a semitransparent mirror intercepting said first optical axis at an angle of 45° and including a view finding optical system disposed rearwardly of said first reflector and receiving the light traversing said first reflector.
Claim 6
Dependent Claim
33 words
The combination of claim 4 wherein said view finding optical system comprises in succession from the front to the rear an imaging lens, a field lens, an erecting prism and an ocular lens.
Claim 7
Dependent Claim
23 words
The combination of claim 1 wherein said lens system and said cassette are disposed in said casing on opposite sides of said casing.
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) | 1979-05-11 | 1979-11-10 | 1980-05-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-05-11 | 1983-11-10 | 1984-05-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-05-11 | 1987-11-10 | 1988-05-11 | $7700.00 | Window Closed / Lapsed |