GB2192291A - Progressive power contact lens - Google Patents
Progressive power contact lens Download PDFInfo
- Publication number
- GB2192291A GB2192291A GB08605351A GB8605351A GB2192291A GB 2192291 A GB2192291 A GB 2192291A GB 08605351 A GB08605351 A GB 08605351A GB 8605351 A GB8605351 A GB 8605351A GB 2192291 A GB2192291 A GB 2192291A
- Authority
- GB
- United Kingdom
- Prior art keywords
- lens
- radius
- power
- contact lens
- optic
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- G—PHYSICS
- G02—OPTICS
- G02C—SPECTACLES; SUNGLASSES OR GOGGLES INSOFAR AS THEY HAVE THE SAME FEATURES AS SPECTACLES; CONTACT LENSES
- G02C7/00—Optical parts
- G02C7/02—Lenses; Lens systems ; Methods of designing lenses
- G02C7/04—Contact lenses for the eyes
- G02C7/041—Contact lenses for the eyes bifocal; multifocal
- G02C7/044—Annular configuration, e.g. pupil tuned
-
- G—PHYSICS
- G02—OPTICS
- G02C—SPECTACLES; SUNGLASSES OR GOGGLES INSOFAR AS THEY HAVE THE SAME FEATURES AS SPECTACLES; CONTACT LENSES
- G02C7/00—Optical parts
- G02C7/02—Lenses; Lens systems ; Methods of designing lenses
- G02C7/04—Contact lenses for the eyes
- G02C7/041—Contact lenses for the eyes bifocal; multifocal
- G02C7/043—Translating type
-
- G—PHYSICS
- G02—OPTICS
- G02C—SPECTACLES; SUNGLASSES OR GOGGLES INSOFAR AS THEY HAVE THE SAME FEATURES AS SPECTACLES; CONTACT LENSES
- G02C7/00—Optical parts
- G02C7/02—Lenses; Lens systems ; Methods of designing lenses
- G02C7/06—Lenses; Lens systems ; Methods of designing lenses bifocal; multifocal ; progressive
- G02C7/061—Spectacle lenses with progressively varying focal power
Landscapes
- Health & Medical Sciences (AREA)
- Ophthalmology & Optometry (AREA)
- Physics & Mathematics (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Lenses (AREA)
- Eyeglasses (AREA)
Abstract
A progressive power contact lens comprises a distance vision central portion and an aspherical peripheral portion of progressive power.
Description
SPECIFICATION
Invention of varifocal contact lens.
Contact Lenses has been with us for very long time but to this state all the contact lenses are available either in single vision or in bifocal form. Bifocal forms are mainly of spectacle shape which have proved to be difficult and cumbersome to fit and patient's inability to adapt to them satisfactarily. Eye being very sensitive organ of the human body finds these lenses unacceptable because they insult the cornea and the eye lids.
My invention of varifocal contact lens does not harm the eye in any way. As the enclosed diagrame shows the construction of the contact lens has distance centre portion and peripheral portion of aspheric construction. Aspheric curve has a different radius at every point. The front centre optic radius can be calculated given the following parametres:
Back centre optic radius
Power of the lens
Centre thickness of the lens
Refractive index of the material
The front peripheral radius is spherical surface which is calculated when the following parametres are known:
Third peripheral radius at a given point (determined by the fitting of the lens)
Addition power of the lens.
Physical thickness at the point.
Refractive index of the material.
As the back surface is aspherical up to the edge of the back centre optic diametre diameter and the front surface is spherical, of two radii, front central optic radius and front optical prepheral optical radius.
Central portion of the lens will produce distance power while the peripheral radius will produce a different power at every point.
To construct a varifocal lens we need to calculate a set of settings for the lathe. This is best illustrated by flow chart diagrame.
Following prescription is a typical forivarifocal specification
Back cenetral optic radius.
Back Central optic diameter.
Overall diameter.
Edge lift
Power ofthe lens (distance)
Maximum addiction.
Diameter at the point of maximum addition.
Centre thickness of the lens.
Refractive index of the material.
All the above specifications will be needed to calculate the following lathe settings.
Back peripheral radius (r2)
Off set Angie FEED
To calculate the front optic radius-the following specifications will be used:
Back central-optic radius.
DISTANCE POWER of the lens.
Centre thickness of the lens.
Refractive index of the material.
To calculate the third radius at the maximum addition point the following data will be used:
Overall diameter.
Back centre optic diameter.
Second peripheral radius.
Edge lift.
Back central optic radius.
To calculate the front optical peripheral radius the following data is required:third radius.
Physical thickness at maximum addition point.
Power of the lens at the- pi̲nt' (distance+reading).
Refractive index of the material.
Lathe and Lens Calculations.
Edge Lift (E.L.)=b2(1-1)
2 r1 r2
Where r2 is peripheral radius.
b is half of periphery i.e. from the edge of back central optic diameter to the overall diameter.
r1 is Back Central optic radius.
E.L. is defined as the perpendicular distancefrom the projection of the back centre optic surface to the edge of the lens.
OFFSET=B.C.O.D.(r2-r1)
2r, where values r, and r2 are same as above B.C.O.D.-is back central optic diameter.
FEED=(r2-r1)2-(OFFSET)2 F1 (Front central optic radius=(1 -n) X 1000.
r1 f1= 1000 F1 f'1=F1- Ct n F',= 1000 f 1 F2=F'1 +B V P (Back vertex power)
F.C.0.R.= 1-n
F2
SEE DIAGRAMME.
ANGLE. sin 0= B C.O.D.
r1 Calculate r3 (any point on the periphery of the lens to the geometric centre of the lens) saggita of O.D. with r2 saggitta of B.C.O.D. with B.C.O.R.
saggitta of B.C.O.D. with r2 saggitta of max. diameter of the add with r2.
r is any radius and y is half the diameter.
S (GD) Total sag of the iens=B.C.O.R. on B.C.O.D.+O.D. on r2-r2 on B.C.O.D.
S, (TD) sag from B.F.O.D. TO O.D.=r2on O.D.-r2 on B.C.O.D.
S2 (ED) is variable according to the maximum add diameter and must be divided proportionally according to S,.
GE=S3=S-S2 r3=CR=The distance between geometric centre to the max. addition point.
CE=B.C.O.R.S3
To calculate Second front optic peripheral radius,
Distance power+Reading power=Reading Rx F3 (1 -n) x 1000
r3 f3= 1000 F3 f= 1000 F'3 f3=F3- pt
n where pt is physical thickness at maximum addition point.
F'3= 1000 ft3
F4=F3+(BVP) F.P.O.R. '(r4)= 1-n F2
Claims (10)
1. Power in the reading area will increase gradually.
2. there is no sudden jump from distance to the reading portion.
3. This lens design allows the wearer to look above and below the eye level for close distances.
4. The gradual power is concentric which fulfills the claim no 3.
5. Lens can be made to any perameter without restrictions.
6. The lens design allows the fitter to determine any central clearance and edge clearance without compromising the fitting of the lens.
7. The lens design allows the fitter to increase or decrease the graduation of power in the reading portion by varing the edge lift of the lens.
8. The back central optic radius and the periphery have no sharp transition so there is no damage to the cornea.
9. The adaptation period for the wearer is no longer than the single vision contact lens.
10. There are no aberrations in the lens as it is made from one piece of material.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB8605351A GB2192291B (en) | 1986-03-04 | 1986-03-04 | Progressive power contact lens. |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB8605351A GB2192291B (en) | 1986-03-04 | 1986-03-04 | Progressive power contact lens. |
Publications (3)
Publication Number | Publication Date |
---|---|
GB8605351D0 GB8605351D0 (en) | 1986-04-09 |
GB2192291A true GB2192291A (en) | 1988-01-06 |
GB2192291B GB2192291B (en) | 1990-08-22 |
Family
ID=10594033
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB8605351A Expired - Fee Related GB2192291B (en) | 1986-03-04 | 1986-03-04 | Progressive power contact lens. |
Country Status (1)
Country | Link |
---|---|
GB (1) | GB2192291B (en) |
Cited By (24)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5225858A (en) * | 1987-06-01 | 1993-07-06 | Valdemar Portney | Multifocal ophthalmic lens |
GB2301196A (en) * | 1995-05-24 | 1996-11-27 | Bausch & Lomb | Contact lens having spherical central zone and aspheric annular zone |
US5702440A (en) * | 1996-01-26 | 1997-12-30 | Allergan | Multifocal ophthalmic lens for dim-lighting conditions |
US5864378A (en) * | 1996-05-21 | 1999-01-26 | Allergan | Enhanced monofocal IOL or contact lens |
WO1999008147A1 (en) * | 1997-08-07 | 1999-02-18 | Vista Optics Limited | Contact lens |
US6210005B1 (en) | 1999-02-04 | 2001-04-03 | Valdemar Portney | Multifocal ophthalmic lens with reduced halo size |
US6231603B1 (en) | 1998-11-10 | 2001-05-15 | Allergan Sales, Inc. | Accommodating multifocal intraocular lens |
US6270218B1 (en) * | 1998-10-26 | 2001-08-07 | Johnson & Johnson Vision Products, Inc. | Contact lenses with off-axis bevel |
US8182531B2 (en) | 2006-12-22 | 2012-05-22 | Amo Groningen B.V. | Accommodating intraocular lenses and associated systems, frames, and methods |
US8465544B2 (en) | 2006-12-29 | 2013-06-18 | Abbott Medical Optics Inc. | Accommodating intraocular lens |
US8545556B2 (en) | 2002-10-25 | 2013-10-01 | Abbott Medical Optics Inc. | Capsular intraocular lens implant |
US8814934B2 (en) | 2006-12-29 | 2014-08-26 | Abbott Medical Optics Inc. | Multifocal accommodating intraocular lens |
US9011532B2 (en) | 2009-06-26 | 2015-04-21 | Abbott Medical Optics Inc. | Accommodating intraocular lenses |
US9039760B2 (en) | 2006-12-29 | 2015-05-26 | Abbott Medical Optics Inc. | Pre-stressed haptic for accommodating intraocular lens |
US9271830B2 (en) | 2002-12-05 | 2016-03-01 | Abbott Medical Optics Inc. | Accommodating intraocular lens and method of manufacture thereof |
US9421089B2 (en) | 2007-07-05 | 2016-08-23 | Visiogen, Inc. | Intraocular lens with post-implantation adjustment capabilities |
US9504560B2 (en) | 2002-01-14 | 2016-11-29 | Abbott Medical Optics Inc. | Accommodating intraocular lens with outer support structure |
US9603703B2 (en) | 2009-08-03 | 2017-03-28 | Abbott Medical Optics Inc. | Intraocular lens and methods for providing accommodative vision |
US9636213B2 (en) | 2005-09-30 | 2017-05-02 | Abbott Medical Optics Inc. | Deformable intraocular lenses and lens systems |
US9814570B2 (en) | 1999-04-30 | 2017-11-14 | Abbott Medical Optics Inc. | Ophthalmic lens combinations |
US9968441B2 (en) | 2008-03-28 | 2018-05-15 | Johnson & Johnson Surgical Vision, Inc. | Intraocular lens having a haptic that includes a cap |
US9987125B2 (en) | 2012-05-02 | 2018-06-05 | Johnson & Johnson Surgical Vision, Inc. | Intraocular lens with shape changing capability to provide enhanced accomodation and visual acuity |
US10722400B2 (en) | 2011-09-12 | 2020-07-28 | Amo Development, Llc | Hybrid ophthalmic interface apparatus and method of interfacing a surgical laser with an eye |
US11707354B2 (en) | 2017-09-11 | 2023-07-25 | Amo Groningen B.V. | Methods and apparatuses to increase intraocular lenses positional stability |
Families Citing this family (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6790232B1 (en) | 1999-04-30 | 2004-09-14 | Advanced Medical Optics, Inc. | Multifocal phakic intraocular lens |
US6406494B1 (en) | 1999-04-30 | 2002-06-18 | Allergan Sales, Inc. | Moveable intraocular lens |
US6616692B1 (en) | 1999-04-30 | 2003-09-09 | Advanced Medical Optics, Inc. | Intraocular lens combinations |
US6599317B1 (en) | 1999-09-17 | 2003-07-29 | Advanced Medical Optics, Inc. | Intraocular lens with a translational zone |
US6551354B1 (en) | 2000-03-09 | 2003-04-22 | Advanced Medical Optics, Inc. | Accommodating intraocular lens |
US6547822B1 (en) | 2000-05-03 | 2003-04-15 | Advanced Medical Optics, Inc. | Opthalmic lens systems |
US6554859B1 (en) | 2000-05-03 | 2003-04-29 | Advanced Medical Optics, Inc. | Accommodating, reduced ADD power multifocal intraocular lenses |
US6537317B1 (en) | 2000-05-03 | 2003-03-25 | Advanced Medical Optics, Inc. | Binocular lens systems |
US6660035B1 (en) | 2000-08-02 | 2003-12-09 | Advanced Medical Optics, Inc. | Accommodating intraocular lens with suspension structure |
US7780729B2 (en) | 2004-04-16 | 2010-08-24 | Visiogen, Inc. | Intraocular lens |
US20030078658A1 (en) | 2001-01-25 | 2003-04-24 | Gholam-Reza Zadno-Azizi | Single-piece accomodating intraocular lens system |
US8062361B2 (en) | 2001-01-25 | 2011-11-22 | Visiogen, Inc. | Accommodating intraocular lens system with aberration-enhanced performance |
US20030078657A1 (en) | 2001-01-25 | 2003-04-24 | Gholam-Reza Zadno-Azizi | Materials for use in accommodating intraocular lens system |
US6576012B2 (en) | 2001-03-28 | 2003-06-10 | Advanced Medical Optics, Inc. | Binocular lens systems |
US6638305B2 (en) | 2001-05-15 | 2003-10-28 | Advanced Medical Optics, Inc. | Monofocal intraocular lens convertible to multifocal intraocular lens |
US20050131535A1 (en) | 2003-12-15 | 2005-06-16 | Randall Woods | Intraocular lens implant having posterior bendable optic |
Citations (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB939016A (en) * | 1961-08-03 | 1963-10-09 | Wilhelm Peter Soehnges | Corneal contact lens |
GB1156454A (en) * | 1965-10-04 | 1969-06-25 | David Volk | Aspheric Corneal Contact Lens Series |
GB1433782A (en) * | 1973-04-28 | 1976-04-28 | Vickrage J D M | Contact lens |
GB1536891A (en) * | 1976-02-12 | 1978-12-29 | Volk D | Ophthalmic lens for presbyopia and aphakia |
GB2026715A (en) * | 1978-05-04 | 1980-02-06 | Spofa Vereinigte Pharma Werke | Hydrophilic contact lens |
GB1561892A (en) * | 1975-10-08 | 1980-03-05 | Jessen Inc Wesley | Lens and method and apparatus for forming the same |
GB2059102A (en) * | 1979-09-24 | 1981-04-15 | Breger Joseph L | Presbyopic contact lens |
GB2117130A (en) * | 1982-03-10 | 1983-10-05 | American Optical Corp | Contact lens having lateral carrier |
GB2139375A (en) * | 1983-04-21 | 1984-11-07 | Benjamin Nuchman | Continuously variable contact lens |
US4525043A (en) * | 1977-11-11 | 1985-06-25 | Leonard Bronstein | Contact lens |
-
1986
- 1986-03-04 GB GB8605351A patent/GB2192291B/en not_active Expired - Fee Related
Patent Citations (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB939016A (en) * | 1961-08-03 | 1963-10-09 | Wilhelm Peter Soehnges | Corneal contact lens |
GB1156454A (en) * | 1965-10-04 | 1969-06-25 | David Volk | Aspheric Corneal Contact Lens Series |
GB1433782A (en) * | 1973-04-28 | 1976-04-28 | Vickrage J D M | Contact lens |
GB1561892A (en) * | 1975-10-08 | 1980-03-05 | Jessen Inc Wesley | Lens and method and apparatus for forming the same |
GB1536891A (en) * | 1976-02-12 | 1978-12-29 | Volk D | Ophthalmic lens for presbyopia and aphakia |
US4525043A (en) * | 1977-11-11 | 1985-06-25 | Leonard Bronstein | Contact lens |
GB2026715A (en) * | 1978-05-04 | 1980-02-06 | Spofa Vereinigte Pharma Werke | Hydrophilic contact lens |
GB2059102A (en) * | 1979-09-24 | 1981-04-15 | Breger Joseph L | Presbyopic contact lens |
GB2117130A (en) * | 1982-03-10 | 1983-10-05 | American Optical Corp | Contact lens having lateral carrier |
GB2139375A (en) * | 1983-04-21 | 1984-11-07 | Benjamin Nuchman | Continuously variable contact lens |
Cited By (36)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5225858A (en) * | 1987-06-01 | 1993-07-06 | Valdemar Portney | Multifocal ophthalmic lens |
GB2301196A (en) * | 1995-05-24 | 1996-11-27 | Bausch & Lomb | Contact lens having spherical central zone and aspheric annular zone |
GB2301196B (en) * | 1995-05-24 | 1999-08-04 | Bausch & Lomb | Contact lens |
US6576011B2 (en) | 1996-01-26 | 2003-06-10 | Advanced Medical Optics, Inc. | Multifocal ophthalmic lens |
US5702440A (en) * | 1996-01-26 | 1997-12-30 | Allergan | Multifocal ophthalmic lens for dim-lighting conditions |
US5919229A (en) * | 1996-01-26 | 1999-07-06 | Allergan | Multifocal opthalmic lens |
US6221105B1 (en) | 1996-01-26 | 2001-04-24 | Allergan | Multifocal ophthalmic lens |
US5864378A (en) * | 1996-05-21 | 1999-01-26 | Allergan | Enhanced monofocal IOL or contact lens |
US6126286A (en) * | 1996-05-21 | 2000-10-03 | Allergan | Enhanced monofocal ophthalmic lens |
WO1999008147A1 (en) * | 1997-08-07 | 1999-02-18 | Vista Optics Limited | Contact lens |
US6270218B1 (en) * | 1998-10-26 | 2001-08-07 | Johnson & Johnson Vision Products, Inc. | Contact lenses with off-axis bevel |
US6231603B1 (en) | 1998-11-10 | 2001-05-15 | Allergan Sales, Inc. | Accommodating multifocal intraocular lens |
US6210005B1 (en) | 1999-02-04 | 2001-04-03 | Valdemar Portney | Multifocal ophthalmic lens with reduced halo size |
US6557998B2 (en) | 1999-02-04 | 2003-05-06 | Advanced Medical Optics, Inc. | Multifocal ophthalmic lens with reduced halo size |
US6435681B2 (en) | 1999-02-04 | 2002-08-20 | Valdemar Portney | Multifocal ophthalmic lens with reduced halo size |
US9814570B2 (en) | 1999-04-30 | 2017-11-14 | Abbott Medical Optics Inc. | Ophthalmic lens combinations |
US9504560B2 (en) | 2002-01-14 | 2016-11-29 | Abbott Medical Optics Inc. | Accommodating intraocular lens with outer support structure |
US8545556B2 (en) | 2002-10-25 | 2013-10-01 | Abbott Medical Optics Inc. | Capsular intraocular lens implant |
US8585758B2 (en) | 2002-10-25 | 2013-11-19 | Abbott Medical Optics Inc. | Accommodating intraocular lenses |
US10206773B2 (en) | 2002-12-05 | 2019-02-19 | Johnson & Johnson Surgical Vision, Inc. | Accommodating intraocular lens and method of manufacture thereof |
US9271830B2 (en) | 2002-12-05 | 2016-03-01 | Abbott Medical Optics Inc. | Accommodating intraocular lens and method of manufacture thereof |
US9636213B2 (en) | 2005-09-30 | 2017-05-02 | Abbott Medical Optics Inc. | Deformable intraocular lenses and lens systems |
US8182531B2 (en) | 2006-12-22 | 2012-05-22 | Amo Groningen B.V. | Accommodating intraocular lenses and associated systems, frames, and methods |
US8496701B2 (en) | 2006-12-22 | 2013-07-30 | Amo Groningen B.V. | Accommodating intraocular lenses and associated systems, frames, and methods |
US8814934B2 (en) | 2006-12-29 | 2014-08-26 | Abbott Medical Optics Inc. | Multifocal accommodating intraocular lens |
US9039760B2 (en) | 2006-12-29 | 2015-05-26 | Abbott Medical Optics Inc. | Pre-stressed haptic for accommodating intraocular lens |
US8465544B2 (en) | 2006-12-29 | 2013-06-18 | Abbott Medical Optics Inc. | Accommodating intraocular lens |
US9421089B2 (en) | 2007-07-05 | 2016-08-23 | Visiogen, Inc. | Intraocular lens with post-implantation adjustment capabilities |
US9968441B2 (en) | 2008-03-28 | 2018-05-15 | Johnson & Johnson Surgical Vision, Inc. | Intraocular lens having a haptic that includes a cap |
US10052194B2 (en) | 2009-06-26 | 2018-08-21 | Johnson & Johnson Surgical Vision, Inc. | Accommodating intraocular lenses |
US9011532B2 (en) | 2009-06-26 | 2015-04-21 | Abbott Medical Optics Inc. | Accommodating intraocular lenses |
US9603703B2 (en) | 2009-08-03 | 2017-03-28 | Abbott Medical Optics Inc. | Intraocular lens and methods for providing accommodative vision |
US10105215B2 (en) | 2009-08-03 | 2018-10-23 | Johnson & Johnson Surgical Vision, Inc. | Intraocular lens and methods for providing accommodative vision |
US10722400B2 (en) | 2011-09-12 | 2020-07-28 | Amo Development, Llc | Hybrid ophthalmic interface apparatus and method of interfacing a surgical laser with an eye |
US9987125B2 (en) | 2012-05-02 | 2018-06-05 | Johnson & Johnson Surgical Vision, Inc. | Intraocular lens with shape changing capability to provide enhanced accomodation and visual acuity |
US11707354B2 (en) | 2017-09-11 | 2023-07-25 | Amo Groningen B.V. | Methods and apparatuses to increase intraocular lenses positional stability |
Also Published As
Publication number | Publication date |
---|---|
GB8605351D0 (en) | 1986-04-09 |
GB2192291B (en) | 1990-08-22 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
PCNP | Patent ceased through non-payment of renewal fee |