US4779964A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Zoom lens with a mechanism for moving a first lens so as to be compactly housed
Assignee: Ricoh Co Ltd
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Filing: 1986-11-10
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Granted: 1988-10-25
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Expires: 2006-11-10
Abstract
Abstract A zoom lens has at least a first group lens and a second group lens which are spaced a greater distance from each other in one of telephoto setting and wide angle setting than the other setting, and a mechanism for moving the first group lens from said one setting toward an image formation plane.
Inventors
- 👤 Toshiro Ozawa
- 👤 Yoshio Fukushima
- 👤 Kenichi Takanashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 22:10
CPC Classifications
G; G02; G02B; G02B7/00; G02B7/02; G02B7/04; G02B7/10; G02B15/00; G02B15/14; G02B15/142; G02B15/1421
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
82 words
A zoom lens comprising at least a first lens and a second lens which are a greater distance from each other in one of telephoto setting and wide angle setting than the other setting, said zoom lens moving along an optical path between said telephoto setting and said wide angle setting, and a mechanism for moving said first lens from said one setting toward an image formation plane when said zoom lens is not in use so as to be compactly housed.
Claim 2
Dependent Claim
82 words
A zoom lens comprising at least a first lens and a second lens which are a greater distance from each other in one of telephoto setting and wide angle setting than the other setting, said zoom lens moving along an optical path between said telephoto setting and said wide angle setting, and a mechanism for moving said first lens from said one setting toward an image formation plane when said zoom lens is not in use so as to be compactly housed.
Claim 3
Dependent Claim
24 words
A zoom lens according to claim 1, wherein said first and second lenses are more spaced from each other in said wide angle setting.
Claim 4
Dependent Claim
25 words
A zoom lens according to claim 1, wherein said first and second lenses are spaced a greater distance from each other in said telephoto setting.
Claim 5
Dependent Claim
26 words
A zoom lens according to claim 1, wherein said first lens is moved toward said image formation plane as closely to said second lens as possible.
Claim 6
Dependent Claim
21 words
A zoom lens according to claim 1, wherein said first lens has positive power and said second lens has negative power.
Claim 7
Dependent Claim
18 words
A zoom lens according to claim 1, wherein each of said first and second lenses has positive power.
Claim 8
Dependent Claim
77 words
A zoom lens according to claim 1, further including a first movable lens barrel supporting said first lens and having a pin, a second movable lens barrel supporting said second lens and having a cam groove, and a third fixed lens barrel having a straight groove extending along an optical axis of the zoom lens, said pin engaging in said cam groove and said straight groove, so that zooming is effected by turning said second lens barrel.
Claim 9
Dependent Claim
28 words
A zoom lens according to claim 7, wherein said third lens barrel has a cam groove contiguous to said straight groove and acting to move said first lens.
Claim 10
Dependent Claim
45 words
A zoom lens according to claim 8, wherein said cam groove of said third lens barrel is of the same shape and size as those of said cam groove of said second lens barrel and can overlap said cam groove of said second lens barrel.
Claim 11
Dependent Claim
17 words
A zoom lens according to claim 7, further including a motor for driving said second lens barrel.
Claim 12
Dependent Claim
89 words
A zoom lens comprising a first lens, a second lens, and a third lens, said first and second lenses being spaced a greater distance from each other in one of telephoto setting and a wide angle setting than the other setting, said zoom lens moving along an optical path between said telephoto setting and said wide angle setting, and a mechanism for moving said first lens from said one setting toward an image formation plane when said zoom lens is not in use so as to be compactly housed.
Claim 13
Dependent Claim
89 words
A zoom lens comprising a first lens, a second lens, and a third lens, said first and second lenses being spaced a greater distance from each other in one of telephoto setting and a wide angle setting than the other setting, said zoom lens moving along an optical path between said telephoto setting and said wide angle setting, and a mechanism for moving said first lens from said one setting toward an image formation plane when said zoom lens is not in use so as to be compactly housed.
Claim 14
Dependent Claim
25 words
A zoom lens according to claim 11, wherein said first and second lenses are greater distance spaced from each other in said wide angle setting.
Claim 15
Dependent Claim
25 words
A zoom lens according to claim 11, wherein said first and second lenses are a greater distance spaced from each other in said telephoto setting.
Claim 16
Dependent Claim
26 words
A zoom lens according to claim 11, wherein said first lens is moved toward said image formation plane as closely to said second lens as possible.
Claim 17
Dependent Claim
27 words
A zoom lens according to claim 11, wherein said first lens has positive power, said second lens has negative power, and said third lens has positive power.
Claim 18
Dependent Claim
27 words
A zoom lens according to claim 11, wherein said first lens has positive power, said second lens has negative power, and said third lens has negative power.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-10-25 | 1992-04-25 | 1992-10-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-10-25 | 1996-04-25 | 1996-10-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-10-25 | 2000-04-25 | 2000-10-25 | $7700.00 | Window Closed / Lapsed |