EP0107444A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Bifocal contact lenses
Assignee: NG Trustees and Nominees Ltd
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Filing: 1983-10-12
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Granted: —
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Expires: 2003-10-12
Abstract
Abstract A bifocal contact lens is described wherein at least the major viewing area is divided into a multiplicity of near and distant vision viewing zones (41, 42, 43, 44), each near vision zone (41, 44) being adjacent to a distant vision zone (42, 43) or middle distance zone and there being at least 3 viewing zones in all, whereby the wearer is able to look through at least 2 zones of different power simultaneously. Normally the lens has at least 2 of each kind of viewing zone and the total surface area of the distant vision zones is substantially equal to the total surface area of the near vision zones.
Inventors
- 👤 John Trevor De Carle
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-07 22:17
CPC Classifications
G; G02; G02B; G02B5/00; G02B5/18; G02B5/1876; G02B5/189; G02B5/1895; G02C; G02C7/00; G02C7/02; G02C7/04; G02C7/041; G02C7/042; G02C7/044; G02C7/045
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
58 words
A bifocal contact lens wherein at least the rmajor viewing area is divided into a multiplicity of near and distant vision viewing zones, each near vision zone being adjacent to a distant vision zone or middle distance zone whereby in normal use substantially equal amounts of light enter the eye through the near vision and distant vision zones.
Claim 2
Dependent Claim
58 words
A bifocal contact lens wherein at least the rmajor viewing area is divided into a multiplicity of near and distant vision viewing zones, each near vision zone being adjacent to a distant vision zone or middle distance zone whereby in normal use substantially equal amounts of light enter the eye through the near vision and distant vision zones.
Claim 3
Dependent Claim
19 words
A lens according to claim 1 in which there are at least 2 of each kind of viewing zone.
Claim 4
Dependent Claim
33 words
A lens according to claim 1 or claim 2 in which the total surface area of the distant vision zones is substantially equal to the total surface area of the near vision zones.
Claim 5
Dependent Claim
31 words
A lens according to any one of the preceding claims in which the distant and near vision viewing zones are produced by machining the front or back surface of the lens.
Claim 6
Dependent Claim
47 words
A lens according to anyone of the preceding claims in which the distant and near vision viewing zones result from the presence in the body of the lens of segments of transparent plastics material having a different refractive index from that of the body of the lens.
Claim 7
Dependent Claim
32 words
A bifocal contact lens wherein the major viewing area comprises at least 4 sectors radiating outwardly from the axis of the lens, me sectors being aiternatery near and distant vision viewing zones.
Claim 8
Dependent Claim
32 words
A bifocal contact lens wherein the major viewing area comprises at least 4 sectors radiating outwardly from the axis of the lens, me sectors being aiternatery near and distant vision viewing zones.
Claim 9
Dependent Claim
14 words
A lens according to claim 6 wherein the sectors are substantially equal in area.
Claim 10
Dependent Claim
22 words
A lens according to claim 6 or claim 7 wherein the sectors radiate from a small central zone having a single power.
Claim 11
Dependent Claim
23 words
A lens according to claim 8 wherein the power of the central zone is the same as that of the distant viewing zones,
Claim 12
Dependent Claim
32 words
A lens according to any one of claims 6 to 9 wherein the total surface area of the distant vision zones substantially equals the total sutface area of the near vision zones.
References Cited (Backward Citations)
No citation records indexed.
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