US3575495A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High speed document lens having five elements
Assignee: International Business Machines Corp
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Filing: 1969-10-27
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Granted: 1971-04-20
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Expires: 1989-10-27
Abstract
Abstract A lens is described having a high light gathering ability which may be employed in document reading and/or sorting machines. The lens includes five lens elements, a first biconvex lens element, a first meniscus lens element, a biconcave lens element, a second meniscus lens element and a second biconvex lens element.
Inventors
- 👤 Raymond E Tibbetts
- 👤 Janusz S Wilczynski
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 13:20
CPC Classifications
G; G02; G02B; G02B13/00; G02B13/24
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
173 words
A lens group comprising first, second, third, fourth and fifth lens elements, said first lens element I having curvatures defined by radii R1 and R2 said second lens element II having curvatures defined by Radii R3 and R4, said their lens element III having curvatures defined by rAdii R5 and R6, said fourth lens element IV having curvatures defined by radii R7 and R8 and said fifth lens element having curvatures defined by radii R9 and R10. Said first, second, third, fourth and fifth lens elements having axial thickness t1, t2, t3, t4 and t5 respectively, said first and second lens elements being separated by an axial airspace S1 said second and third lens elements being separated by an axial airspace S2 said third and fourth lens elements being separated by an axial airspace S3 and said fourth and fifth lens elements being separated by an axial airspace S4. and wherein said radii, thicknesses and air spaces are within limits as follows where f is the equivalent focal length of the lens group:
Claim 2
Dependent Claim
173 words
A lens group comprising first, second, third, fourth and fifth lens elements, said first lens element I having curvatures defined by radii R1 and R2 said second lens element II having curvatures defined by Radii R3 and R4, said their lens element III having curvatures defined by rAdii R5 and R6, said fourth lens element IV having curvatures defined by radii R7 and R8 and said fifth lens element having curvatures defined by radii R9 and R10. Said first, second, third, fourth and fifth lens elements having axial thickness t1, t2, t3, t4 and t5 respectively, said first and second lens elements being separated by an axial airspace S1 said second and third lens elements being separated by an axial airspace S2 said third and fourth lens elements being separated by an axial airspace S3 and said fourth and fifth lens elements being separated by an axial airspace S4. and wherein said radii, thicknesses and air spaces are within limits as follows where f is the equivalent focal length of the lens group:
Claim 3
Dependent Claim
17 words
A lens group according to claim 1 wherein said radii, thickness and air-spaces are specifically as follows:
References Cited (Backward Citations)
US2586866A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-04-19 | 1974-10-19 | 1975-04-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-04-19 | 1978-10-19 | 1979-04-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-04-19 | 1982-10-19 | 1983-04-20 | $7700.00 | Window Closed / Lapsed |