FORM 2
THE PATENTS ACT, 1970
(Act 39 of 1970)
And
THE PATENTS RULE, 2003
COMPLETE SPECIFICATION
(See Section 10 and Rule 13)
1. Title: Novel Refractive EDOF Toric Intraocular Lens for Continuous Vision
2. I. Applicant(s):
(a) Name: Biotech Vision Care Pvt. Ltd.
(b) Nationality: Indian
(c) Address: Block 1, Abhishree Corporate Park,
Opp. Swagat Bungalows BRTS Stop,
Bopal-Ambli Road
Ahmedabad- 380058, Gujarat, India.
3. Preamble of description
The-following specification particularly describes the invention and the manner in which it is to be performed.


TITLE OF INVENTION
Novel Refractive EDOF Toric Intraocular Lens for Continuous Vision
FIELD OF INVENTION
The present invention relates to intraocular lens. More particularly the present invention is related to the intraocular lens (IOL) with incorporated toricity along with extended depth of focus (EDOF), which provides continuous vision to the cataract patients from far distant to near objects with minimized halos and glare and corrects the pre-existing corneal astigmatism.
BACKGROUND OF INVENTION
The Optical system of the eye is well understood in which outer portion contains cornea and sclera. The iris choroid and ciliary body belongs to the middle part of the eye. The middle part of the eye, also houses the natural crystalline lens. Whereas inner layer of the eye contains retina, where image formation occurs due to combined optical system of the eye. Further in this optical system, cornea has generally greater and nearly constant optical power in comparison to the natural crystalline lens. It is the natural crystalline lens, which changes its optical power, in order to adjust the required total power of the eye to image the various distant objects on the retina.
The change in the optical power of the natural crystalline lens occurs by changing its shape, due the ciliary muscles contraction and relaxation. The accommodative nature of the natural crystalline lens, is responsible for providing the suitable power to the eye to image the various distant objects at the retina. But accommodative power as well as the transparency of the natural crystalline lens gradually gets compromised with the age of person. Loss of transparency in the natural crystalline lens is known as cataract. After the cataract formation, surgery need to be performed to remove the cataract from the capsular bag, and suitable artificial lens needs to be implanted in order to

perform the same job as the natural crystalline lens, but with limited object distances. Therefore, the person with implanted IOL, cannot see the objects which is beyond the limit of vision distance of the IOL. Thus the person using this type of IOL, has to wear prescription glasses for viewing other distance objects. This is because implanted IOL has its fixed power/focal length and aperture.
The present novel invention is an IOL which has an extended depth of focus (EDOF) with embedded toricity, which can be used to correct the patient's pre-existing corneal astigmatism and enables to get the continuous vision for near to distant objects. It minimizes the spectacle dependency.
SUMMARY OF INVENTION
The present invention Novel Refractive EDOF Toric Intraocular Lens for Continuous Vision is a lens which provides continuous vision from far distance to functional near distance objects with minimized halos and glare and corrects the preexisting corneal astigmatism wherein the IOL is extended depth of focus along with incorporated embedded toricity. The lens of present invention is the fourth zone 60-degree segment design to provide the balanced energy distribution at larger pupil diameter like scotopic condition along with correction of pre-existing corneal astigmatism wherein the Controlled spherical aberration and 60 degree refractive segments in the fourth zone on the anterior toric surface makes the nominal power independent from the pupil size (eye pupil) and minimize haloes and glares in the visual acuity of the patient after implanting the lens in the eye along with correction of pre¬existing corneal astigmatism. Also, the EDOF Toric intraocular lens balances the nominal power and provide pupil independence along with correction of pre-existing corneal astigmatism. The reduced thickness of the EDOF TORIC-IOL helps in unfolding of the IOL during implantation, through small incision. The lens described in present invention provides balanced light distribution and maintain the image quality and contrast because of the introduction of concentric circular zone and segmented design." The embedded toricity

balances the pre-existing corneal astigmatism along with the extended depth of focus.
The present invention of novel refractive EDOF Toric IOL is extended depth of focus along with incorporated embedded toricity, which provides continuous vision from far distance to near distance objects with minimized halos and glare and corrects the preexisting corneal astigmatism.
Other main objective of the proposed novel refractive EDOF Toric IOL is to maintain the uniform energy distribution, along with embedded compensatory toricity, throughout the extended focal depth. Further this lens minimizes the specs dependency of the patients after getting implanted in the capsular bag.
Other main objective of the present invention of refractive EDOF-TORIC IOL is the fourth zone 60-degree segment design on the anterior toric surface to provide the balanced energy distribution at larger pupil diameter.
The other object of the present invention Novel Refractive EDOF Toric Intraocular Lens for Continuous Vision is the optimized power distribution on each concentric circular zone and controlled zone width on the anterior toric surface provides the continuous range of vision for daily activities along with correction of pre-existing corneal astigmatism.
Controlled spherical aberration and 60 degree refractive segments in the fourth zone on the anterior toric surface makes the nominal power independent from the pupil size (eye pupil) and minimize haloes and glares in the visual acuity of the patient after implanting the lens in the eye along with correction of pre-existing corneal astigmatism.
Another object of the present invention Novel Refractive EDOF Toric Intraocular Lens for Continuous Vision is the fourth zone 60-degree segment design to provide the balanced energy distribution at larger pupil diameter like scotopic condition along with correction of pre-existing corneal astigmatism.
Yet another object of the present invention Novel Refractive EDOF Toric Intraocular Lens for Continuous Vision is to minimize glares and halos

by providing controlled spherical aberration at each zone on the anterior toric surface.
Further this refractive EDOF Toric-IOL balances the nominal power and provide pupil independence along with correction of pre-existing corneal astigmatism.
Another main objective of the EDOF TORIC IOL is the optimized energy distribution in each annular zone to maintain the good contrast irrespective of the pupil size and light conditions,
Another main objective of the EDOF Toric IOL is the optimized energy distribution in each annular zone along with correction of pre-existing corneal astigmatism to maintain the good contrast irrespective of the pupil size and light conditions.
Another main objective of the EDOF toric IOL is to provide the vision at functional intermediate distance and functional near distance which are missing the traditional multifocal IOLs and monofocal IOLs along with correction of pre-existing corneal astigmatism.
The reduced thickness of the EDOF TORIC-IOL helps in unfolding of the IOL during implantation, through small incision.
This lens provides balanced light distribution and maintain the image quality and contrast because of the introduction of concentric circular zone and segmented design. The embedded toricity balances the pre-existing corneal astigmatism along with the extended depth of focus.
BRIEF DESCRIPTION OF DRAWINGS OF INVENTION
The main objective of the present invention of refractive EDOF TORIC IOL is to provide extended depth of focus to get continuous vision from far to functional near distance along with the correction of pre-existing corneal astigmatism present in the eye. The variation in the radius of curvature along the two perpendicular axes maintains toricity of the IOL to correct the pre-existing corneal astigmatism of the eye.

Figure 1 represents the anterior surface of the invention.
Figure 2 describes the zonal distribution of the optic portion of the invention.
Figure 3 describes the fourth zone 60 degree arc segmentation.
Figure 4 represents the side view of the invention with enlarged view of 360 degree square edge.
Figure 5 describes about the perspective view of the embodiment.
Figure 6 explains about the power distribution/ optical output result (autofocus scan) of the invention with optimized circular zones.
DETAILED DESCRIPTION OF THE INVENTION
The following paragraph describes about the design of EDOF Toric IOL and its outcomes and advantages of the design. The subject matter is explained with the drawings at required places, where in like reference numerals are used.
The present invention of intraocular lens is called extended depth of focus toric intraocular lens (EDOF Toric IOL) to provide the continuous vision with the correction of pre-existing corneal astigmatism. This lens offers clear vision from far distance to near distance up to closer distances. This new additional feature is providing a near vision along with intermediate vision with the correction of pre-existing corneal astigmatism and neutralize or reduce the net eye system astigmatism.
The Refractive EDOF property is achieved based on the principle of refraction. Refraction is the bending of light ray when passing through one medium to another medium. Based on this principle the present invention is developed. The present invention incorporates the asymmetric power distribution with controlled spherical aberration to produce an extended depth of focus while maintaining the contrast even at different pupil size.

This design strategy involves the strategic placement of different lens powers within the IOL structure to extend the range of clear vision and achieve depth of focus. By manipulating the powers, it is possible to direct light from various distances onto the retina with greater precision. This approach can significantly enhance visual acuity and contrast sensitivity across a continuum of distances, providing patients with a more seamless visual experience, The implementation of asymmetric power distribution is done with calculation as to make it independent of the pupil size such that the contrast never suffers whatever the lighting condition be.
Spherical aberration occurs when light rays passing through a lens or mirror near its edge are refracted more than those near the center, causing the light to focus at different points along the optical axis, creating a blurred or distorted image. Positive spherical aberration means that the peripheral rays are focused closer to the lens or mirror than the central rays, while negative spherical aberration means that the peripheral rays are focused further away. The combination of positive and negative spherical aberration can be used to increase the depth of focus in an optical system. By carefully balancing these aberrations, it is possible to create a situation where light rays from different distances along the optical axis come into focus within a small region, extending the range over which objects appear sharp and in focus. This phenomenon can actually extend the depth of focus in an optical system because it broadens the region where the light rays overlap and produce a reasonably sharp image. In detail, when an optical system has spherical aberration, the focal point for rays passing through the edge of the lens is farther from the lens than the focal point for rays passing through the center. As a result, there is a range of distances along the optical axis where these different focal points overlap, creating an extended depth of focus.
The present invention refractive EDOF Toric IOL is related to intraocular lenses, which are used in the cataract surgery. This refractive EDOF Toric lens is developed with hydrophobic or hydrophilic acrylic material having the refractive index of 1.40-1.6. The EDOF Toric intraocular lens design is having single piece structure as described in the figure 1. It shows the front surface of the intraocular lens, which is called as anterior

surface of the invention. This surface is the main objective of this invention, having the refractive circular zones and 60 degree refractive segments on the toric anterior surface to provide the continuous vision. The toricity is given on the anterior surface like cylindrical surface. The anterior base surface having two radius of curvatures with 90 degree apart to provide the toricity. The difference between two powers gives the cylindrical power of Hie lens. On this toricity surface refractive zones and 60 degree segments are developed to - -provide the depth of field' along with the required toricity. The posterior surface of the invention is represented by figure 2, have the single radius of curvature for entire posterior surface.
Figure 1 represents the embodiment of the invention with optic portion of the intraocular lens 101, which is responsible for the light ray refraction and continuous vision inside the eye. The part number 103 represent the axis marks of the toricity. On the axis marks, lens having the lower power of the lens and at 90 degrees from the axis mark lens having the higher power of the lens. The difference between these two powers gives the toricity value or cylinder power of the lens. These axis marks are useful to align the lens with the corneal astigmatism axis and neutralize the total eye system astigmatism or compensate the pre-existing corneal astigmatism.
The modified C type haptics 104 provides maximum contact angle with the capsular bag, which provides the better rotational stability in the eye. The peripheral zone 102 has been given negative curvature to the IOL anterior surface to control the thickness of the lens to fold and unfold easily during the implantation of the IOL by using micro incision process.
Figure 2 shows the center optic portion 20 of the intraocular lens having the innovative design to provide extended depth of focus to see the objects from far distance to near distance with continuous vision with the correction of corneal astigmatism. The center optic portion having the toricity on the base surface and on the toricity surface, six concentric annular refractive zones 201, 202, 203, 204 & 205 with in the 4.7 mm clear optic zone on the anterior surface of the optic portion.

Figure 3 shows a detailes view of the fourth zone , represents the 60 degree refractive segments in the fourth zone 301, 302, 303, 304 & 305 from the center of the invention to balance the energy distribution at larger pupil diameters. By optimizing the zonal refraction and zone width, the power can be adjusted as per requirement and achieved the required depth of focus for continuous vision.
Figure 4 represents the posterior surface side view with the 360 degree posterior surface square edge 401 of the intraocular lens. The design of the square edge 402 will provide proper shrinkage of the capsular bag with the posterior surface of the intraocular lens and prevent the early stage PCO (Posterior Capsular Opacification).
Further figure 5 shows the perspective view 50 of the invention with with central optics 501 which has incorpaorated the zonal power distribution with controlled spherical aberration designed on a toric base 502 for correction of corneal astigmatism.
In the design and development of invention, Hydrophobic or hydrophilic materials are used with variable range of refractive index 1.4-1.6. During the development of the invention, the size of the optic portion has been taken 6 mm with 13.0 mm overall diameter, but as per requirement, these sizes will vary accordingly. By using above mentioned methodology, around 3.5 D depth of field has been achieved by optimizing the zone radius and power distribution on the concentric circular zones. The optimization of the zone diameters and power distribution on the concentric circular zones on the toric anterior base surface, allow us to achieve desired depth of field along with toricity to compensate the pre-existing corneal astigmatism.
Optical Material: Hydrophobic or Hydrophilic material
Refractive Index: 1.40-1.6
Optic Surface: Aspheric
Optical Size of the IOL: 6 mm (variable according to requirement)
Overall size of the IOL: 13 mm (variable according to requirement)

Number of concentric refractive circular zones in the clear optic area: 5 (variable according to requirement)
Toricity is given on the anterior side of the IOL in the described design. The toricity can be given on the posterior side .of the IOL surface also as per requirement.
The invention of the Refractive EDOF IOL given satisfactory results on the optical bench performance. Continuous and extended depth of focus observed in the output result from 1.0 D to 3.5 D by varying the zone power and optimizing the zone radius. Figure 6 represents two curves overlapped or separated with some distance and each curve having the depth of field more than 2.0 D. This depth will be varied accordingly the varying the zone power and the optimizing the zone radius. In the figure 7 two curves represents the two powers on the IOL surface at two different plane (horizontal and perpendicular plane) and the difference between the two powers gives the cylinder power of the lens. The average power of the two powers considered as spherical equivalent power of the IOL. The cylindrical power vary from 0.5 D to 10.0 D or more as per requirement. The depth of field of the intraocular lens measured by using through focus curve. The Modulation Transfer Function (MTF) curve in the fig 6 shows the energy distribution of the IOL at 3 mm aperture size. The achieved depth of field is useful to see the objects from far distance to intermediate and near distance objects along with distance objects for daily activities. The toricity of the IOL compensate or naturalize the pre-exiting corneal astigmatism.

I/We claim:
1. A novel refractive EDOF Toric Intraocular lens for continuous vision comprising of:
a refractive EDOF Toric lens made of hydrophobic or hydrophilic acrylic material having refractive index of 1.40-1.60 wherein, the lens further comprises of:
a modified C type haptics providing maximum contact angle with the capsular bag to provide better rotational stability in the eye.
an optical portion responsible for the light ray refraction and continuous vision wherein the optical portion further consisting of:
a posterior surface having a single radius of curvature for entire posterior surface wherein the design of the 360 degree posterior surface square edge of the intraocular lens providing proper shrinkage of the capsular bag with the posterior surface and prevent the early stage PCO (Posterior Capsular Opacification),
an anterior surface having the refractive circular zones and 60 degree refractive segments to provide the continuous vision characterized in that,
a center optic portion having the toricity on the base and on the toricity surface comprising of six concentric annular refractive zones with in the 4.7 mm clear optic zone on the anterior surface of the optic portion,

a peripheral zone (9) having a negative curvature to the IOL anterior surface to control the thickness of the lens, and an axis mark of the toricity lens having lower power of the lens and at 90 degrees from the axis mark lens having the higher power of lens.
2. The novel refractive EDOF Toric Intraocular lens for continuous vision as claimed in claim 1, wherein the size of the optical portion is 6 mm and the overall diameter of the intraocular lens is 13 mm.
3. The novel refractive EDOF Toric Intraocular lens for continuous vision as claimed in claim 1, invention will provide clear continuous vision from far to near distances along with the intermediate vision with the correction of corneal astigmatism.
4. The novel refractive EDOF Toric Intraocular lens for continuous vision as claimed in claim 1, wherein the power can be adjusted as per the requirement and the required depth of focus for continuous vision can be achieved by optimizing the zonal refraction and zone width of the one of the six concentric annular refractive zone.
5. The novel refractive EDOF Toric Intraocular lens for continuous vision as claimed in claim 1, wherein the optimization of the zone diameters and power distribution on the concentric circular zones on the toric anterior base surface allows to achieve desired depth of the field along with the toricity to compensate the pre-existing corneal astigmatism.

6. The novel refractive EDOF Toric Intraocular lens for continuous vision as
claimed in claim 1, wherein around 3.5 D depth of field is achieved by
__:"____ optimizing the zone radius and power distribution on the concentric circular
zones.
7. The novel refractive EDOF Toric Intraocular lens for continuous vision as
claimed in claim 1, wherein the achieved depth of the field enables to see the
objects from far distance to intermediate and near distance objects along with
distance objects for daily activities.