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US4549794A Expired / Lapsed US ⏱️ 0.0 years remaining

Hydrophilic bifocal contact lens

Assignee: WJ ACQUISITION CORP
•
Filing: 1983-05-05
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Granted: 1985-10-29
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Expires: 2003-05-05
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Abstract

Abstract Hydrophilic bifocal corneal contact lenses of the alternating-vision type having a critical set of dimensions for the various elements which results in a surprising increase in the success rate of persons wearing these improved lenses.

Inventors

  • 👤 Samuel Loshaek
  • 👤 Malcolm G. Townsley

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 01:31
CPC Classifications
G; G02; G02C; G02C7/00; G02C7/02; G02C7/04; G02C7/041; G02C7/043; G02C7/045; G02C7/048

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 204 words
A hydrophilic bifocal corneal contact lens comprising a concave rear surface and a convex front surface, said lens in frontal projection comprising: (a) a perimeter in the form of a truncated circle having a diameter of 14.5 mm, said truncation forming the bottom of said lens and having a height of about 1.5 mm, (b) a reading segment above the truncation having an upper boundary below the center of said truncated circle, the distance from said center to said upper boundary along a line bisecting the lens being from 1.5 to 3.5 mm, and (c) a distant-vision segment located such that the center of said truncated circle is within said distant-vision segment; wherein the prescriptions and maximum thickness at the center of such truncated circle are as follows: ______________________________________ Distant-Vision Add to Distant Vision Maximum Prescription, Prescriptions to Achieve Thickness t Diopters Reading Prescription, Diopters At Center, mm ______________________________________ -4 1.25 0.08 -2 1.25 0.08 0 1.25 0.08 +2 1.25 0.14 -4 2.50 0.08 -2 2.50 0.08 0 2.50 0.10 +2 2.50 0.15 +6 2.50 0.24 ______________________________________ whereby when said lens is worn by a patient the distant-vision segment covers at least 70 percent of the patient's pupil when the patient looks straight ahead.
Claim 2
Dependent Claim 204 words
A hydrophilic bifocal corneal contact lens comprising a concave rear surface and a convex front surface, said lens in frontal projection comprising: (a) a perimeter in the form of a truncated circle having a diameter of 14.5 mm, said truncation forming the bottom of said lens and having a height of about 1.5 mm, (b) a reading segment above the truncation having an upper boundary below the center of said truncated circle, the distance from said center to said upper boundary along a line bisecting the lens being from 1.5 to 3.5 mm, and (c) a distant-vision segment located such that the center of said truncated circle is within said distant-vision segment; wherein the prescriptions and maximum thickness at the center of such truncated circle are as follows: ______________________________________ Distant-Vision Add to Distant Vision Maximum Prescription, Prescriptions to Achieve Thickness t Diopters Reading Prescription, Diopters At Center, mm ______________________________________ -4 1.25 0.08 -2 1.25 0.08 0 1.25 0.08 +2 1.25 0.14 -4 2.50 0.08 -2 2.50 0.08 0 2.50 0.10 +2 2.50 0.15 +6 2.50 0.24 ______________________________________ whereby when said lens is worn by a patient the distant-vision segment covers at least 70 percent of the patient's pupil when the patient looks straight ahead.
Claim 3
Dependent Claim 201 words
A hydrophilic bifocal corneal contact lens comprising a concave rear surface and a convex front surface, said lens in frontal projection comprising: (a) a perimeter in the form of a truncated circle having a diameter of 14.5 mm, said truncation forming the bottom of said lens and having a height greater than 1 mm, (b) a reading segment above the truncation having an upper boundary below the center of said truncated circle, the distance from said center to said upper boundary along a line bisecting the lens being 2 mm, and (c) a distant-vision segment located such that the center of said truncated circle is within said distant-vision segment; wherein the prescriptions and maximum thickness at the center of such truncated circle are as follows: ______________________________________ Distant-Vision Add to Distant Vision Maximum Prescription, Prescriptions to Achieve Thickness t Diopters Reading Prescription, Diopters At Center, mm ______________________________________ -4 1.25 0.08 -2 1.25 0.08 0 1.25 0.08 +2 1.25 0.14 -4 2.50 0.08 -2 2.50 0.08 0 2.50 0.10 +2 2.50 0.15 +6 2.50 0.24 ______________________________________ whereby when said lens is worn by a patient the distant-vision segment covers at least 70 percent of the patient's pupil when the patient looks straight ahead.
Claim 4
Dependent Claim 201 words
A hydrophilic bifocal corneal contact lens comprising a concave rear surface and a convex front surface, said lens in frontal projection comprising: (a) a perimeter in the form of a truncated circle having a diameter of 14.5 mm, said truncation forming the bottom of said lens and having a height greater than 1 mm, (b) a reading segment above the truncation having an upper boundary below the center of said truncated circle, the distance from said center to said upper boundary along a line bisecting the lens being 2 mm, and (c) a distant-vision segment located such that the center of said truncated circle is within said distant-vision segment; wherein the prescriptions and maximum thickness at the center of such truncated circle are as follows: ______________________________________ Distant-Vision Add to Distant Vision Maximum Prescription, Prescriptions to Achieve Thickness t Diopters Reading Prescription, Diopters At Center, mm ______________________________________ -4 1.25 0.08 -2 1.25 0.08 0 1.25 0.08 +2 1.25 0.14 -4 2.50 0.08 -2 2.50 0.08 0 2.50 0.10 +2 2.50 0.15 +6 2.50 0.24 ______________________________________ whereby when said lens is worn by a patient the distant-vision segment covers at least 70 percent of the patient's pupil when the patient looks straight ahead.
Claim 5
Dependent Claim 202 words
A hydrophilic bifocal corneal contact lens comprising a concave rear surface and a convex front surface, said lens in frontal projection comprising: (a) a perimeter in the form of a truncated circle having a diameter of 14 to 15 mm, said truncation forming the bottom of said lens and having a height of 1.5 mm, (b) a reading segment above the truncation having an upper boundary below the center of said truncated circle, the distance from said center to said upper boundary along a line bisecting the lens being 2 mm, and (c) a distant-vision segment located such that the center of said truncated circle is within said distant-vision segment; wherein the prescriptions and maximum thickness at the center of such truncated circle are as follows: ______________________________________ Distant-Vision Add to Distant Vision Maximum Prescription, Prescriptions to Achieve Thickness t Diopters Reading Prescription, Diopters At Center, mm ______________________________________ -4 1.25 0.08 -2 1.25 0.08 0 1.25 0.08 +2 1.25 0.14 -4 2.50 0.08 -2 2.50 0.08 0 2.50 0.10 +2 2.50 0.15 +6 2.50 0.24 ______________________________________ whereby when said lens is worn by a patient the distant-vision segment covers at least 70 percent of the patient's pupil when the patient looks straight ahead.
Claim 6
Dependent Claim 202 words
A hydrophilic bifocal corneal contact lens comprising a concave rear surface and a convex front surface, said lens in frontal projection comprising: (a) a perimeter in the form of a truncated circle having a diameter of 14 to 15 mm, said truncation forming the bottom of said lens and having a height of 1.5 mm, (b) a reading segment above the truncation having an upper boundary below the center of said truncated circle, the distance from said center to said upper boundary along a line bisecting the lens being 2 mm, and (c) a distant-vision segment located such that the center of said truncated circle is within said distant-vision segment; wherein the prescriptions and maximum thickness at the center of such truncated circle are as follows: ______________________________________ Distant-Vision Add to Distant Vision Maximum Prescription, Prescriptions to Achieve Thickness t Diopters Reading Prescription, Diopters At Center, mm ______________________________________ -4 1.25 0.08 -2 1.25 0.08 0 1.25 0.08 +2 1.25 0.14 -4 2.50 0.08 -2 2.50 0.08 0 2.50 0.10 +2 2.50 0.15 +6 2.50 0.24 ______________________________________ whereby when said lens is worn by a patient the distant-vision segment covers at least 70 percent of the patient's pupil when the patient looks straight ahead.

References Cited (Backward Citations)

US3031927A Cited
US4202848A Cited
US4199231A Cited
US4318595A Cited
GB2033101A Cited
GB2031178A Cited
US4324461A Cited
EP0062178A1 Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1988-10-28 1989-04-29 1989-10-29 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1992-10-28 1993-04-29 1993-10-29 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1996-10-28 1997-04-29 1997-10-29 $7700.00 Window Closed / Lapsed

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