US3635546A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Retrofocus-type lens system
Assignee: Nikon Corp
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Filing: 1970-01-20
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Granted: 1972-01-18
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Expires: 1990-01-20
Abstract
Abstract A wide angle retrofocus lens system consists of seven lenses L1 through L7. Lens L1 is a positive meniscus with its convex surface directed to an object. Lens L2 is a first negative meniscus and lens L3 is a second negative meniscus, and both of the convex surfaces of these lenses L2 and L3 are directed to an object. Lens L4 is a positive and lens L5 is a negative lenses. Lens L6 is a positive meniscus having concave surface directed to an object. Lens L7 is a positive lens.
Inventors
- 👤 Ikuo Mori
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 05:44
CPC Classifications
G; G02; G02B; G02B13/00; G02B13/04
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
77 words
A retrofocus-type lens system comprising a positive meniscus lens (L1) the convex surface of which is for direction toward an object to be photographed, negative meniscus lenses (L2, L3) the convex surfaces of which are for direction toward the object, a positive lens (L4), a negative lens (L5), a positive meniscus lens (L6) the concave surface of which is for direction toward the object, and a positive lens (L7) of which the detailed data is as follows:
Claim 2
Dependent Claim
77 words
A retrofocus-type lens system comprising a positive meniscus lens (L1) the convex surface of which is for direction toward an object to be photographed, negative meniscus lenses (L2, L3) the convex surfaces of which are for direction toward the object, a positive lens (L4), a negative lens (L5), a positive meniscus lens (L6) the concave surface of which is for direction toward the object, and a positive lens (L7) of which the detailed data is as follows:
Claim 3
Dependent Claim
77 words
A retrofocus-type lens system comprising a positive meniscus lens (L1) the convex surface of which is for direction toward an object to be photographed, negative meniscus lenses (L2, L3) the convex surfaces of which are for direction toward the object, a positive lens (L4), a negative lens (L5), a positive meniscus lens (L6) the concave surface of which is for direction toward the object, and a positive lens (L7) of which the detailed data is as follows:
Claim 4
Dependent Claim
77 words
A retrofocus-type lens system comprising a positive meniscus lens (L1) the convex surface of which is for direction toward an object to be photographed, negative meniscus lenses (L2, L3) the convex surfaces of which are for direction toward the object, a positive lens (L4), a negative lens (L5), a positive meniscus lens (L6) the concave surface of which is for direction toward the object, and a positive lens (L7) of which the detailed data is as follows:
References Cited (Backward Citations)
FR83412E
Cited
US3512874A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-01-17 | 1975-07-19 | 1976-01-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-17 | 1979-07-19 | 1980-01-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-17 | 1983-07-19 | 1984-01-18 | $7700.00 | Window Closed / Lapsed |