Patent US788900A successfully refreshed from Google Patents.
Patent US3901585A successfully refreshed from Google Patents.
US3901585A
Expired / Lapsed
US
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Zoom lens assembly
Assignee: Xerox Corp
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Filing: 1973-10-23
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Granted: 1975-08-26
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Expires: 1993-10-23
Abstract
Abstract A zoom lens assembly for projecting images from an object plane to the image plane at magnifications from approximately 17 times to approximately 29 times and operating in the wavelength range from 0.38 to 0.54 microns. The zoom lens assembly comprises four members, including a front fixed member, two cam controlled moving members, and a rear fixed member. A diaphragm is mounted within the rear moving member and is controlled by a third cam to maintain a constant f/number aperture at the long conjugate. In a preferred embodiment, the cams which control the movable members are designed so that equal angular rotations of the cam sleeve into which the cam slots are cut changes the magnification by equal amounts.
Inventors
- 👤 Harold F Bennett
- 👤 Wai-Min Liu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 20:38
CPC Classifications
G; G02; G02B; G02B13/00; G02B13/24
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
184 words
A zoom lens assembly consisting essentially of an axially fixed front member, an axially movable second member, an axially movable third member, and an axially fixed rear fourth member, the first fixed member comprising, from the front to the rear, a double convex element and a negative meniscus element convex to the front, the axially movable second member comprising, from the front to the rear, a positive meniscus element convex to the front, a doublet comprising a double convex element, the rear surface of which is affixed to a first double concave element, and a second double concave element, said third movable member comprising, from the front to the rear a negative meniscus element convex to the front, a first double convex element; a first doublet comprising a second double convex element the rear surface of which is affixed to a first negative meniscus element concave to the front and a second doublet comprising a positive meniscus element, the rear surface of which is affixed to a second negative meniscus element concave to the front, the fourth fixed member comprising a positive meniscus element.
Claim 2
Dependent Claim
184 words
A zoom lens assembly consisting essentially of an axially fixed front member, an axially movable second member, an axially movable third member, and an axially fixed rear fourth member, the first fixed member comprising, from the front to the rear, a double convex element and a negative meniscus element convex to the front, the axially movable second member comprising, from the front to the rear, a positive meniscus element convex to the front, a doublet comprising a double convex element, the rear surface of which is affixed to a first double concave element, and a second double concave element, said third movable member comprising, from the front to the rear a negative meniscus element convex to the front, a first double convex element; a first doublet comprising a second double convex element the rear surface of which is affixed to a first negative meniscus element concave to the front and a second doublet comprising a positive meniscus element, the rear surface of which is affixed to a second negative meniscus element concave to the front, the fourth fixed member comprising a positive meniscus element.
Claim 3
Dependent Claim
187 words
A zoom lens assembly consisting essentially of an axially fixed front first member, an axially movable second member, an axially movable third member, and an axially fixed rear fourth member, the first fixed member comprising, from the front to the rear, a positive meniscus element concave to the front and a negative meniscus element convex to the front, the axially movable second member comprising, from the front to the rear, a positive meniscus element concave to the front, a double convex element, the rear surface of which is affixed to a first double concave element, and a second double concave element, said third movable member comprising, from the front to the rear, a negative meniscus element convex to the front, a positive meniscus element concave to the front, a first doublet comprising a double convex element, the rear surface of which is affixed to a negative meniscus element concave to the front and a second doublet comprising a double convex element, the rear surface of which is affixed to a negative meniscus element concave to the front, and the fourth fixed member comprising a positive meniscus element.
Claim 4
Dependent Claim
187 words
A zoom lens assembly consisting essentially of an axially fixed front first member, an axially movable second member, an axially movable third member, and an axially fixed rear fourth member, the first fixed member comprising, from the front to the rear, a positive meniscus element concave to the front and a negative meniscus element convex to the front, the axially movable second member comprising, from the front to the rear, a positive meniscus element concave to the front, a double convex element, the rear surface of which is affixed to a first double concave element, and a second double concave element, said third movable member comprising, from the front to the rear, a negative meniscus element convex to the front, a positive meniscus element concave to the front, a first doublet comprising a double convex element, the rear surface of which is affixed to a negative meniscus element concave to the front and a second doublet comprising a double convex element, the rear surface of which is affixed to a negative meniscus element concave to the front, and the fourth fixed member comprising a positive meniscus element.
Claim 5
Dependent Claim
11 words
A zoom lens assembly made substantially according to the following specifications:
Claim 6
Dependent Claim
11 words
A zoom lens assembly made substantially according to the following specifications:
Claim 7
Dependent Claim
11 words
A zoom lens assembly made substantially according to the following specifications:
Claim 8
Dependent Claim
11 words
A zoom lens assembly made substantially according to the following specifications:
Claim 9
Dependent Claim
11 words
A zoom lens assembly made substantially according to the following specifications:
Claim 10
Dependent Claim
11 words
A zoom lens assembly made substantially according to the following specifications:
References Cited (Backward Citations)
US3558225A
Cited
US3609005A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-08-25 | 1979-02-24 | 1979-08-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-08-25 | 1983-02-24 | 1983-08-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-08-25 | 1987-02-24 | 1987-08-26 | $7700.00 | Window Closed / Lapsed |