US3751136A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Variable focal length anamorphotic cinecamera systems
Assignee: Individual
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Filing: 1971-08-27
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Granted: 1973-08-07
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Expires: 1991-08-27
Abstract
Abstract A variable focal length cinecamera system consisting of an afocal auxiliary lens system by means of which, through modification of the spacing between optical elements constituting the said lens system, the focal length of the system can be changed while the intercept length is maintained constant, and of a succeeding permanently installed basic lens focused at infinity. An afocal anamorphotic system is provided between the afocal auxiliary lens system and the basic lens.
Inventors
- 👤 K Kirchhoff
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 08:06
CPC Classifications
G; G02; G02B; G02B13/00; G02B13/08; G02B15/00; G02B15/14; G02B15/22
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
117 words
A variable focal length cinecamera system comprising an afocal auxiliary lens system having a plurality of optical elements capable of being moved relative to each other to change the focal length of said lens system, the intercept length being maintained constant, a succeeding permanently installed basic lens focused at infinity, a camera diaphragm arranged between said afocal auxiliary lens system and said basic lens, and an afocal anamorphotic system located between said afocal auxiliary lens system and said basic lens adjacent said diaphragm, said diaphragm being arranged at a point in the optical system where the cross section of the imaging ray bundle is at a minimum whereby the size of said anamorphotic system can be minimized.
Claim 2
Dependent Claim
117 words
A variable focal length cinecamera system comprising an afocal auxiliary lens system having a plurality of optical elements capable of being moved relative to each other to change the focal length of said lens system, the intercept length being maintained constant, a succeeding permanently installed basic lens focused at infinity, a camera diaphragm arranged between said afocal auxiliary lens system and said basic lens, and an afocal anamorphotic system located between said afocal auxiliary lens system and said basic lens adjacent said diaphragm, said diaphragm being arranged at a point in the optical system where the cross section of the imaging ray bundle is at a minimum whereby the size of said anamorphotic system can be minimized.
Claim 3
Dependent Claim
108 words
A variable focal length cinecamera system comprising an afocal auxiliary lens system having a plurality of optical elements capable of being moved relative to each other to change the focal length of said lens system, the intercept length being maintained constant, a succeeding permanently installed basic lens focused at infinity, an afocal anamorphotic system consisting of at least two achromatic prisms located between said afocal auxiliary lens system and said basic lens, and a view-finder telescope, a face of one of said prisms being used to split off part of the light traveling through said system to enable the view-finder image to be observed through said view-finder telescope.
Claim 4
Dependent Claim
108 words
A variable focal length cinecamera system comprising an afocal auxiliary lens system having a plurality of optical elements capable of being moved relative to each other to change the focal length of said lens system, the intercept length being maintained constant, a succeeding permanently installed basic lens focused at infinity, an afocal anamorphotic system consisting of at least two achromatic prisms located between said afocal auxiliary lens system and said basic lens, and a view-finder telescope, a face of one of said prisms being used to split off part of the light traveling through said system to enable the view-finder image to be observed through said view-finder telescope.
Claim 5
Dependent Claim
106 words
A variable focal length cinecamera system comprising an afocal auxiliary lens system having a plurality of optical elements capable of being moved relative to each other to change the focal length of said lens system, the intercept length being maintained constant, a succeeding permanently installed basic lens focused at infinity, an afocal anarmophotic system located between said afocal auxiliary lens system and said basic lens, a view-finder telescope, and a partially mirrored face within said afocal anamorphotic system, said partially mirrored face serving to split off part of the light traveling through said system to enable the view-finder image to be observed through said view-finder telescope.
Claim 6
Dependent Claim
106 words
A variable focal length cinecamera system comprising an afocal auxiliary lens system having a plurality of optical elements capable of being moved relative to each other to change the focal length of said lens system, the intercept length being maintained constant, a succeeding permanently installed basic lens focused at infinity, an afocal anarmophotic system located between said afocal auxiliary lens system and said basic lens, a view-finder telescope, and a partially mirrored face within said afocal anamorphotic system, said partially mirrored face serving to split off part of the light traveling through said system to enable the view-finder image to be observed through said view-finder telescope.
Claim 7
Dependent Claim
48 words
A cinecamera system as claimed in claim 3 in which said anamorphotic system comprises at least two cylindrical lenses and a partially reflective mirror arranged between said lenses, said mirror serving to split off the light for the view-finder image which is observed through said view finder telescope.
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) | 1976-08-06 | 1977-02-05 | 1977-08-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-08-06 | 1981-02-05 | 1981-08-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-08-06 | 1985-02-05 | 1985-08-07 | $7700.00 | Window Closed / Lapsed |