Indian Patents. 216048:A MULTIFOCAL OPTHALMIC LENSES

Title of Invention	A MULTIFOCAL OPTHALMIC LENSES
Abstract	The invention provides methods for designing lenses useful for correcting presbyopin that permits variation of the speed of the power change from distance to near vision power or near to distance vision power. The rate of change may be symmer- tical around the maltificational or slower OIL either side of the midpoint.

Full Text	Invention The invention relates to ophthalmic lcnses, In particular, the invention provides lenses that use more than one optical power, or focal length, and are useful in the correction of presbyopia. 10 Background of the Invention As an individual ages, the eye is less able to accommodate, or bend the natural lens, to focus on objects that are relatively near to the observer. This condition is known as presbyopia. Additionally, for persons who have had their natural lens removed and an intraocular lens inserted as a replacement, the ability to 15 accommodate is totally absent Among the methods used to correct for the eye's failure to accommodate is the mono-vision system in which a person is fitted with one contact lens for distance vision and one lens for near vision. The mono-vision system permits the lens wearer 20 to distinguish both distance and near objects, but is disadvantageous in that a substantial loss in depth perception results. In another type of multifocal contact lenses, the optic zone of each lens is provided with more than one power. For example, the optic zone may have both 25 distance and near power, which the eye uses simultaneously. Neither of these methods provides good results in terms of visual acuity and lens wearer satisfaction. Thus, a need exists for lenses that both provide correction for the wearer's inability to accommodate and that overcome some or all of the 30 disadvantages of known lenses. WO 2004/042454 PCT/US20O3/O34218 2 Brief Description of the Drawings FIG. 1 is a graphic depiction of the power maps for progressive lens designs resulting from Equation L 5 FIG. 2 is a graphic depiction of the power maps for progressive lens designs tesulting from Equation 1. Detailed Description of the Invention and Preferred Embodiments The invention provides methods for designing lenses useful for correcting 10 presbyopia, lenses incorporating such designs, and methods for producing these lenses. In one embodiment, the method of the invention permits variation of the speed, or contour, of the power change from distance to near vision power or near to distance vision power. The result of this variation is that there is a better distribution of the distance and near vision powers within the multifocal zone and, thus, 15 improved visual acuity and wearer satisfaction. In one embodiment, the invention provides a multifocal ophthalmic lens comprising, consisting essentially of and consisting of an optic zone having one or more multifocal power zones wherein a speed and a contour for the zone is 20 determined by the following equation: Add(3) = Addpcak * (1 /(a * (1 +(x/xc)2c)) (1) wherein; 25 Add(x) is actual instantaneous add power at any point x on a surface of the lens; x is a point on the lens surface at a distance x from the center; a is a constant and preferably is 1; Addpeak is the full peak dioptric add power, or sdd power required for near vision correction; 30 xc is the cut off semi-diameter or the midpoint in the power transition from distance to near power, or near to distance power; WO 2004/042454 PCT/US2003/034218 3 n is a variable between 1 and 40, preferably between 1 and 20; and Add is a value that is equal to the difference in power between the near vision power and distance vision power of the lens. 5 In Equation I, n is the variable that controls the slope of the progression from near to distance vision power and distance to near vision power in the lens. The less the value of n, the more gradual the progression will be. 10 In a second embodiment, the invention provides a multifocal ophthalmic lens . comprising, consisting essentially of, and consisting of an optic zone having one or more multifocal power zones wherein a speed and a contour for the zone is determined by the following equation: 15 Add(r)= Addpeak (1 /(a (1 + (x/xc)2) * n) (II) (wherein: Add(x) is actual instantaneous add power at any point x on a surface of the lens; x is a point on the lens surface at a distance x from the center; 20 a is a constant and preferably is 1: Addpeak is the full peak dioptric add power; xe is the cutoff semi-diameter; n is is a variable between 1 and 40, preferably between 1 and 20; and Add is a value that is equal to the difference in power between the near vision power 25 and distance vision power of the lens. In a third embodiment, the invention provides a multifocal ophthalmic leans comprising, consisting essentially of, and consisting of an optic zone having one or in one multifocal power zones wherein a speed and a contour for the zone is 30 determined by the following equation: WO 2004/042454 PCT/US2003/034218 4 Add(I) = Addpeak (I(a(1 + (x/xc)4)n) (III) wherein: 5 Add(x) is actual instanraneous add power at any point x on a surface of the lens; x is a point an the lens surface at a distance x from the center; a is a constant and preferably is 1; d is an arbitrary value between 1 and 40; Addpeak is the full peak dioptric add power; 10 Xc is the cutoff semi-diameter;; n is between 1 and 40, preferably between 1 and 20; and Add is a value that is equal to the difference in power between the near vision power and distance vision power of the lens. 15 For purposes of the invention, by "ophthalmic lens" is meant a spectacle lens, contact lens, intraocular fens, or the like. Preferably, the lenses of the invention are contact lenses.. By "speed." or "contour" is meant the slope of the power change from near to distance power. By "distance vision power" is meant the amount of refractive power required to correct the wearer's distance vision acuity to the desired 20 degree. By "near vision power" is meant the amount of refractive power required to correct the wearer's near vision acuity to the desired degree. In the lenses of the invention, the multifocal power zones may be on the object-side, or from, surface, the eye-side, or rear, surface, or both surfaces. The 25 multifocai power zones have at least two regions of differing power alternating between distance and near vision power. Intermediate power is provided as a consequence of the power progression between the peak of the power of the near and distance vision regions. In the lenses of the invention, the distance, near, and intermediate optical powers are spherical or toric powers. 30 WO 2004/042454 PCT/US2003/034218 5 In Figure 1 is graphically depicted the power progression in four different multifocal power zone designs resulting from Equation I. In each design, the near vision power is at the center of the zone and the distance vision power is at or 5 towards the periphery of the zone. By periphery is meant the region or area farthest from the center of the zone. The values used in Equation I for each of the designs is set forth in the following Table 1. 10 In Figure 2 is graphically depicted the power progression for three different multifocal power zone designs resulting from Equation I. The values used in Equation I for each of the designs is set forth in the following Table 1. 15 In each of Figures 1 and 2 is depicted the add power change as the power departs from the optic center of the lens. The design of the invention provides for a smooth, continuous variation in power from the optical center of the lens to the periphery of the optic zone. Additionally, the design permits a controllable rate of 20 change and position of the power variation. Equations I through III each have a value of n that is the same on either side of xc. As an alternative, the value of n can be a first value when x WO 2004/042454 PCT/US2003/034218 6 second value for x> xc. In this embodiment, x = xC3 n may be the first or second value. 5 The lenses of the invention may be made from any suitable lens forming materials. IIIustrative materials for formation of soft contact lenses include, without limitation silicone elastomers, silicone-containing macromers including, without limitation, those disclosed in United States Patent Nos, 5,371,147, 5,314,960, and 5,057,578 incorporated in their entireties herein by reference, hydrogels, silicone- 10 containing bydrogels, and the like and combinations thereof More preferably, the surface is a siloxane, or contains a siloxane functionality, including, without limitation, polydimethyl siloxaue macromcrs, methacryloxypropyl polyalkyl siloxanes, and mixtures thereof, silicone hydrogel or a hydrogel, such as etafilcon A. 15 A preferred contact lens material is a poly 2-hydroxyethyl methacrylate polymers, meaning, having a peak molecular weight between about 25,000 and about 80,000 and a polydispersity of less than about 1:5 to less than about 3.5 respectively and covalenlly bonded thereon, at least one cross-linkable functional group. This material is described in Attorney Docket Number VTN 588, United 20 States Serial NO, 60/363,630 incorporated herein in its entirety by reference. As yet another alternative, the lens material may be any material suitable for forming ophthalmic lens other than contact lenses. For example, spectacle lens materials may be used inducting, without limitation, polycarbonates, such as 25 bisphenol A polycarbonates, allyt digtycol carbonates, such as diethylene glycol bisallyl carbonate (CR-3 9TM) allylic esters, such as triallyl cyanurate, triallyl phosphate and triallyl citrate, acrylic esters, acrylates, methacrylaics, such as 30 WO 2004/042454 PCT/US2003/034218 7 methyl- ethyl- and butyl methacrylates and acrylates, styrenics, polyesters, and the like and combinations thereof. Additionally, materials for forming intraocular lenses include, without limitation, polymethyl methacrylate, hydroxyethyl 5 melhacrylate, inert clear plastics, silicone-based polymers, and the like and combinations thereof. Curing of the lens material may be carried out by any convenient method. For example, the material may be deposited within a mold and cured by thermal, 10 irradiation, chemical, electromagnetic radiation curing and the like and combinations thereof. Preferably, for contact lens embodiments, molding is carried out using ultraviolet light or using the full spectrum of visible light. More specifically, the precise conditions suitable for curing the lens material will depend on the material selected and the lens to be formed. Suitable processes are disclosed in U.S. Patent 15 No. 5,540,410 incorporated herein in its cntirety by reference. WO 2004/042454 PCT/US2003/034218 8 What is claimed is; 1. A multifocal ophthalmic lens, comprising an optic zone comprising one or 5 more multifocal power zones having a distance vision power and a near vision power and wherein a speed for the optic zone is determined by the following equation: Add(k) = Addpeak (1 /(a (1 + (x /xc)2n)) 10 (I) wherein: Add(x) is an instantaneous add power at any point x on a surface of the lens; x is a point on the lens surface at a distance x from the center of the lens; a is a constant; 15 Addpeak is a full peak dioptric add power; xe is a cutoff semi-diameter; n is a variable between 1 and 40; and Add is a value that is equal to the difference in power between the near vision power and distance vision power of the lens, 20 2. The Jens of claim 1, wherein a is 1 and n is between 1 and 20. 3. The lens of claim 1 or 2, wherein the lens is a contact lens. 15 4. A multifocal ophthalmic lens, comprising of an optic zone comprising one or more multifocal power zones having a distance vision power and a near vision power wherein a speed far the optic zone is determined by the following equation: Add(k) = Addperk (1/(a * (1 + (x /x c)2) * 11) 30 (II) wherein: WO 2004/042454 PCT/US2003/034218 9 Add(x) is an instantaneous add power at any point x on a surface of the lens; x is a point on the lens surface at a distance x from the center ofthe iens; 5 a is a constant: Addpeak is a full peak dioptric add power, xc is a cutoff semi- diameter; n is a variable between 1 and 40; and Add is a value that is equal to or leas than the difference in power between the near 10 vision power and distance vision power of the tens. 5. The lens of claim 4, wherein a is I and n is between 1 and 20. 6. The lens of claim 4 or 5, wherein the lens is a contact lens. 15 7. A multifocal ophthalmic lens, comprising of an optic zone comprising one or more multifocal power zones having a distance vision power and a near vision power wherein a speed for the optic zone is determined by the fallowing equation: 20 Add(2) = Addpeak (1/(a(1 + (x/xc)4)*n) (III) wherein: Add(x) is an instantaneous add power at any point x on a surface of the lens; 25 x is a point on the lens surface at a distance x from the center of the lens; a is a constant; d is an arbitrary value between 1 and 40 ; Addpeak is a full peak dioptric add power; xc is a cutoff semi-diameter; 30 n is between 1 and 20; and WO 2004/042454 PCT/US2003/034218 10 Add is a value that is equal to or less than the difference in power between the near vision power and distance vision power of the lens. 5 8. The lens of claim 7, wherein a is 1 and n is between 1 and 20, 9. The lens of claim 7 or 8, wherein the Jens is a contact lens. 10. The lens of claim 1, wherein n is s first value for x 10 x > xc and is the first value or the second value for x = xc 11. The lens of claim 4, wherein n is a first value for x x > xc and is the first value or the second value for x =xc 15 12. The lens of claim 7, wherein n is a first vuhic for x x > xc and is the first value or the second value for x = xc The invention provides methods for designing lenses useful for correcting presbyopin that permits variation of the speed of the power change from distance to near vision power or near to distance vision power. The rate of change may be symmer- tical around the maltificational or slower OIL either side of the midpoint.

Full Text

Invention
The invention relates to ophthalmic lcnses, In particular, the invention
provides lenses that use more than one optical power, or focal length, and are useful
in the correction of presbyopia.
10 Background of the Invention
As an individual ages, the eye is less able to accommodate, or bend the
natural lens, to focus on objects that are relatively near to the observer. This
condition is known as presbyopia. Additionally, for persons who have had their
natural lens removed and an intraocular lens inserted as a replacement, the ability to
15 accommodate is totally absent
Among the methods used to correct for the eye's failure to accommodate is
the mono-vision system in which a person is fitted with one contact lens for distance
vision and one lens for near vision. The mono-vision system permits the lens wearer
20 to distinguish both distance and near objects, but is disadvantageous in that a
substantial loss in depth perception results.
In another type of multifocal contact lenses, the optic zone of each lens is
provided with more than one power. For example, the optic zone may have both
25 distance and near power, which the eye uses simultaneously.
Neither of these methods provides good results in terms of visual acuity and
lens wearer satisfaction. Thus, a need exists for lenses that both provide correction
for the wearer's inability to accommodate and that overcome some or all of the
30 disadvantages of known lenses.

WO 2004/042454 PCT/US20O3/O34218
2
Brief Description of the Drawings
FIG. 1 is a graphic depiction of the power maps for progressive lens designs
resulting from Equation L
5 FIG. 2 is a graphic depiction of the power maps for progressive lens designs
tesulting from Equation 1.
Detailed Description of the Invention and Preferred Embodiments
The invention provides methods for designing lenses useful for correcting
10 presbyopia, lenses incorporating such designs, and methods for producing these
lenses. In one embodiment, the method of the invention permits variation of the
speed, or contour, of the power change from distance to near vision power or near to
distance vision power. The result of this variation is that there is a better distribution
of the distance and near vision powers within the multifocal zone and, thus,
15 improved visual acuity and wearer satisfaction.
In one embodiment, the invention provides a multifocal ophthalmic lens
comprising, consisting essentially of and consisting of an optic zone having one or
more multifocal power zones wherein a speed and a contour for the zone is
20 determined by the following equation:
Add(3) = Addpcak * (1 /(a * (1 +(x/xc)2c))
(1)
wherein;
25 Add(x) is actual instantaneous add power at any point x on a surface of the lens;
x is a point on the lens surface at a distance x from the center;
a is a constant and preferably is 1;
Addpeak is the full peak dioptric add power, or sdd power required for near vision
correction;
30 xc is the cut off semi-diameter or the midpoint in the power transition from distance
to near power, or near to distance power;

WO 2004/042454 PCT/US2003/034218
3
n is a variable between 1 and 40, preferably between 1 and 20; and
Add is a value that is equal to the difference in power between the near vision power
and distance vision power of the lens.
5
In Equation I, n is the variable that controls the slope of the progression from near to
distance vision power and distance to near vision power in the lens. The less the
value of n, the more gradual the progression will be.
10 In a second embodiment, the invention provides a multifocal ophthalmic lens .
comprising, consisting essentially of, and consisting of an optic zone having one or
more multifocal power zones wherein a speed and a contour for the zone is
determined by the following equation:
15 Add(r)= Addpeak *(1 /(a *(1 + (x/xc)2) * n)
(II)
(wherein:
Add(x) is actual instantaneous add power at any point x on a surface of the lens;
x is a point on the lens surface at a distance x from the center;
20 a is a constant and preferably is 1:
Addpeak is the full peak dioptric add power;
xe is the cutoff semi-diameter;
n is is a variable between 1 and 40, preferably between 1 and 20; and
Add is a value that is equal to the difference in power between the near vision power
25 and distance vision power of the lens.
In a third embodiment, the invention provides a multifocal ophthalmic leans
comprising, consisting essentially of, and consisting of an optic zone having one or
in one multifocal power zones wherein a speed and a contour for the zone is
30 determined by the following equation:

WO 2004/042454 PCT/US2003/034218
4
Add(I) = Addpeak *(I(a*(1 + (x/xc)4)*n)
(III)
wherein:
5 Add(x) is actual instanraneous add power at any point x on a surface of the lens;
x is a point an the lens surface at a distance x from the center;
a is a constant and preferably is 1;
d is an arbitrary value between 1 and 40;
Addpeak is the full peak dioptric add power;
10 Xc is the cutoff semi-diameter;;
n is between 1 and 40, preferably between 1 and 20; and
Add is a value that is equal to the difference in power between the near vision power
and distance vision power of the lens.
15 For purposes of the invention, by "ophthalmic lens" is meant a spectacle
lens, contact lens, intraocular fens, or the like. Preferably, the lenses of the invention
are contact lenses.. By "speed." or "contour" is meant the slope of the power change
from near to distance power. By "distance vision power" is meant the amount of
refractive power required to correct the wearer's distance vision acuity to the desired
20 degree. By "near vision power" is meant the amount of refractive power required to
correct the wearer's near vision acuity to the desired degree.
In the lenses of the invention, the multifocal power zones may be on the
object-side, or from, surface, the eye-side, or rear, surface, or both surfaces. The
25 multifocai power zones have at least two regions of differing power alternating
between distance and near vision power. Intermediate power is provided as a
consequence of the power progression between the peak of the power of the near
and distance vision regions. In the lenses of the invention, the distance, near, and
intermediate optical powers are spherical or toric powers.

30
WO 2004/042454 PCT/US2003/034218
5
In Figure 1 is graphically depicted the power progression in four different
multifocal power zone designs resulting from Equation I. In each design, the near
vision power is at the center of the zone and the distance vision power is at or
5 towards the periphery of the zone. By periphery is meant the region or area farthest
from the center of the zone. The values used in Equation I for each of the designs is
set forth in the following Table 1.

10 In Figure 2 is graphically depicted the power progression for three different
multifocal power zone designs resulting from Equation I. The values used in
Equation I for each of the designs is set forth in the following Table 1.

15
In each of Figures 1 and 2 is depicted the add power change as the power
departs from the optic center of the lens. The design of the invention provides for a
smooth, continuous variation in power from the optical center of the lens to the
periphery of the optic zone. Additionally, the design permits a controllable rate of
20 change and position of the power variation.
Equations I through III each have a value of n that is the same on either side
of xc. As an alternative, the value of n can be a first value when x

WO 2004/042454 PCT/US2003/034218
6
second value for x> xc. In this embodiment, x = xC3 n may be the first or second
value.
5 The lenses of the invention may be made from any suitable lens forming
materials. IIIustrative materials for formation of soft contact lenses include, without
limitation silicone elastomers, silicone-containing macromers including, without
limitation, those disclosed in United States Patent Nos, 5,371,147, 5,314,960, and
5,057,578 incorporated in their entireties herein by reference, hydrogels, silicone-
10 containing bydrogels, and the like and combinations thereof More preferably, the
surface is a siloxane, or contains a siloxane functionality, including, without
limitation, polydimethyl siloxaue macromcrs, methacryloxypropyl polyalkyl
siloxanes, and mixtures thereof, silicone hydrogel or a hydrogel, such as etafilcon A.
15 A preferred contact lens material is a poly 2-hydroxyethyl methacrylate
polymers, meaning, having a peak molecular weight between about 25,000 and
about 80,000 and a polydispersity of less than about 1:5 to less than about 3.5
respectively and covalenlly bonded thereon, at least one cross-linkable functional
group. This material is described in Attorney Docket Number VTN 588, United
20 States Serial NO, 60/363,630 incorporated herein in its entirety by reference.
As yet another alternative, the lens material may be any material suitable for
forming ophthalmic lens other than contact lenses. For example, spectacle lens
materials may be used inducting, without limitation, polycarbonates, such as
25 bisphenol A polycarbonates, allyt digtycol carbonates, such as diethylene glycol
bisallyl carbonate (CR-3 9TM) allylic esters, such as triallyl cyanurate, triallyl
phosphate and triallyl citrate, acrylic esters, acrylates, methacrylaics, such as
30

WO 2004/042454 PCT/US2003/034218
7
methyl- ethyl- and butyl methacrylates and acrylates, styrenics, polyesters, and the
like and combinations thereof. Additionally, materials for forming intraocular
lenses include, without limitation, polymethyl methacrylate, hydroxyethyl
5 melhacrylate, inert clear plastics, silicone-based polymers, and the like and
combinations thereof.
Curing of the lens material may be carried out by any convenient method.
For example, the material may be deposited within a mold and cured by thermal,
10 irradiation, chemical, electromagnetic radiation curing and the like and combinations
thereof. Preferably, for contact lens embodiments, molding is carried out using
ultraviolet light or using the full spectrum of visible light. More specifically, the
precise conditions suitable for curing the lens material will depend on the material
selected and the lens to be formed. Suitable processes are disclosed in U.S. Patent
15 No. 5,540,410 incorporated herein in its cntirety by reference.

WO 2004/042454 PCT/US2003/034218
8
What is claimed is;
1. A multifocal ophthalmic lens, comprising an optic zone comprising one or
5 more multifocal power zones having a distance vision power and a near vision
power and wherein a speed for the optic zone is determined by the following
equation:
Add(k) = Addpeak * (1 /(a *(1 + (x /xc)2n))
10 (I)
wherein:
Add(x) is an instantaneous add power at any point x on a surface of the lens;
x is a point on the lens surface at a distance x from the center of the lens;
a is a constant;
15 Addpeak is a full peak dioptric add power;
xe is a cutoff semi-diameter;
n is a variable between 1 and 40; and
Add is a value that is equal to the difference in power between the near vision power
and distance vision power of the lens,
20
2. The Jens of claim 1, wherein a is 1 and n is between 1 and 20.
3. The lens of claim 1 or 2, wherein the lens is a contact lens.
15 4. A multifocal ophthalmic lens, comprising of an optic zone comprising one or
more multifocal power zones having a distance vision power and a near vision
power wherein a speed far the optic zone is determined by the following equation:
Add(k) = Addperk * (1/(a * (1 + (x /x c)2) * 11)
30 (II)
wherein:

WO 2004/042454 PCT/US2003/034218
9
Add(x) is an instantaneous add power at any point x on a surface of the lens;
x is a point on the lens surface at a distance x from the center ofthe iens;
5 a is a constant:
Addpeak is a full peak dioptric add power,
xc is a cutoff semi- diameter;
n is a variable between 1 and 40; and
Add is a value that is equal to or leas than the difference in power between the near
10 vision power and distance vision power of the tens.
5. The lens of claim 4, wherein a is I and n is between 1 and 20.
6. The lens of claim 4 or 5, wherein the lens is a contact lens.
15
7. A multifocal ophthalmic lens, comprising of an optic zone comprising one or
more multifocal power zones having a distance vision power and a near vision
power wherein a speed for the optic zone is determined by the fallowing equation:
20
Add(2) = Addpeak *(1/(a*(1 + (x/xc)4)*n)
(III)
wherein:
Add(x) is an instantaneous add power at any point x on a surface of the lens;
25 x is a point on the lens surface at a distance x from the center of the lens;
a is a constant;
d is an arbitrary value between 1 and 40 ;
Addpeak is a full peak dioptric add power;
xc is a cutoff semi-diameter;
30 n is between 1 and 20; and

WO 2004/042454 PCT/US2003/034218
10
Add is a value that is equal to or less than the difference in power between the near
vision power and distance vision power of the lens.
5 8. The lens of claim 7, wherein a is 1 and n is between 1 and 20,
9. The lens of claim 7 or 8, wherein the Jens is a contact lens.
10. The lens of claim 1, wherein n is s first value for x 10 x > xc and is the first value or the second value for x = xc
11. The lens of claim 4, wherein n is a first value for x x > xc and is the first value or the second value for x =xc
15 12. The lens of claim 7, wherein n is a first vuhic for x x > xc and is the first value or the second value for x = xc

The invention provides methods for designing lenses useful for correcting presbyopin that permits variation of the
speed of the power change from distance to near vision power or near to distance vision power. The rate of change may be symmer-
tical around the maltificational or slower OIL either side of the midpoint.

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Patent Number

216048

Indian Patent Application Number

01010/KOLNP/2005

PG Journal Number

10/2008

Publication Date

07-Mar-2008

Grant Date

06-Mar-2008

Date of Filing

30-May-2005

Name of Patentee

JOHNSON & JOHNSON VISION CARE, INC,

Applicant Address

7500 CENTURION PARKWAY, SUITE 100, JACKSONVILLE, FL 32256, UNITED STATES OF AMERICA, A FLORIDA CORPORATION.

Inventors:

#	Inventor's Name	Inventor's Address
1	JEFFREY H. ROFFMAN	307 EDGEWATER BRANCH DRIVE, JACKSONVILLE, FLORIDA 32259.
2	DAOUD R. ISKANDER	180 HAWTHORNE ROAD, HAWTHORNE,QUEENSLAND 4171.
3	BRETT A. DAVIS	3/48 RIALTO STREET, COOPAROO, QUEENS LAND 4151.
4	MICHAEL J. COLLINS	LOT 8, MT. NEBO ROAD MT. NEBO, QUEENSLAND 4520.

PCT International Classification Number

G02C 7/02

PCT International Application Number

PC T/US2003/034218

PCT International Filing date

2003-10-28

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1	10/284,613	2002-10-31	U.S.A.