US3576358A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical system with continuously variable magnification
Assignee: Olympus Corp
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Filing: 1968-04-15
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Granted: 1971-04-27
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Expires: 1988-04-15
Abstract
Abstract An optical system for focusing the image of an object at continuously variable magnification on a surface substantially perpendicular to the optical axis and having two lens elements of positive refractive power axially movable relative to each other to vary the focal length of the system. A stop is fixed in the system relative to the image surface approximately in the midpoint of the range of movement of the front focal point of the two positive elements during relative movement of the same while the image is focused in the surface. The focal lengths of the two positive elements satisfy the relationship 0.6 f1<f2<3 f1 unless a negative lens element is located in front of the two positive lens elements in a fixed axial relationship of the rear focal point of the negative element to the aforementioned front focal point. In this arrangement, the focal lengths of the two positive elements need satisfy only the relationship 0.6 f1<f2<8 f1.
Inventors
- 👤 Yoshisada Hayamizu
- 👤 Satoru Sakamoto
- 👤 Nobuo Yamashita
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:04
CPC Classifications
G; G02; G02B; G02B15/00; G02B15/14; G02B15/142; G02B15/1421
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
198 words
In an optical system having an axis and including objective means for focusing an image of an object at continuously variable magnification on a surface substantially perpendicular to said axis, the objective means including two lens components having positive refractive power and respective focal lengths f1, f2, said components being axially movable relative to each other, and the effective focal length of said objective means being varied by the relative movement of said components, the improvement which comprises: a. a stop at a substantially fixed position relative to said surface and substantially in the midpoint of the range of movement of the front focal point of said two components during said relative movement while said image is focused in said surface. b. said stop and said components defining an exit pupil of said objective means spaced from said surface in a direction away from said objective means a distance greater than the effective focal length of said components during said relative moment, said surface being a plane; and c. a plurality of optical fibers jointly constituting an image transmitting system and an image receiving end surface of said image transmitting system, said end surface extending in said plane.
Claim 2
Dependent Claim
198 words
In an optical system having an axis and including objective means for focusing an image of an object at continuously variable magnification on a surface substantially perpendicular to said axis, the objective means including two lens components having positive refractive power and respective focal lengths f1, f2, said components being axially movable relative to each other, and the effective focal length of said objective means being varied by the relative movement of said components, the improvement which comprises: a. a stop at a substantially fixed position relative to said surface and substantially in the midpoint of the range of movement of the front focal point of said two components during said relative movement while said image is focused in said surface. b. said stop and said components defining an exit pupil of said objective means spaced from said surface in a direction away from said objective means a distance greater than the effective focal length of said components during said relative moment, said surface being a plane; and c. a plurality of optical fibers jointly constituting an image transmitting system and an image receiving end surface of said image transmitting system, said end surface extending in said plane.
Claim 3
Dependent Claim
20 words
In a system as set forth in claim 1, said focal lengths f1, f2 satisfying the relationship 0.6f1< f2< 3f1.
Claim 4
Dependent Claim
49 words
In a system as set forth in claim 1, a further lens component having negative refractive power coaxially located in front of said two components, the rear focal point of said further lens component being in a fixed position relative to said front focal point of said two components.
Claim 5
Dependent Claim
18 words
In a system as set forth in claim 1, said focal lengths f1, f2 satisfying the relationship 0.6f1<f2<8f1.
Claim 6
Dependent Claim
17 words
In a system as set forth in claim 1, said focal lengths f1, f2 being substantially equal.
References Cited (Backward Citations)
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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) | 1974-04-26 | 1974-10-26 | 1975-04-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-04-26 | 1978-10-26 | 1979-04-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-04-26 | 1982-10-26 | 1983-04-27 | $7700.00 | Window Closed / Lapsed |