US3619044A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Rigid gas permeable contact lens with softer edge portion
Assignee: American Optical Corp
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Filing: 1970-02-18
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Granted: 1971-11-09
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Expires: 1990-02-18
Abstract
Abstract A rigid, oxygen permeable contact lens formed of the plastic material poly (4-methyl pentene-1) with a soft swellable plastic grafted on the poly (4-methyl pentene-1) lens as the edge of the lens. Method of making such lenses.
Inventors
- 👤 Pandurang M Kamath
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 10:48
CPC Classifications
G; G02; G02C; G02C7/00; G02C7/02; G02C7/04; B; B29; B29D; B29D11/00; B29D11/00009; B29D11/00038; B29D11/00076; G02B; G02B1/00; G02B1/04; G02B1/041; G02B1/043
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
69 words
A rigid, gas permeable, contact lens of concavo-convex form in section, with the concave surface substantially conforming to the cornea of the eye, with a soft edge, said lens being formed of the polymer poly (4-methyl pentene-1) said polymer having an oxygen permeability of about 6,500 as measured in permeability units of P X 1012 (cc. cm/cm.2 sec. cm. Hg) and said edge being a hydrophilic polyacrylic acid polymer.
References Cited (Backward Citations)
US3489491A
Cited
US3551035A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-11-08 | 1975-05-10 | 1975-11-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-08 | 1979-05-10 | 1979-11-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-08 | 1983-05-10 | 1983-11-09 | $7700.00 | Window Closed / Lapsed |