Diffractive intraocular lens

Abstract

The present invention refers to an intraocular lens provided with specific diffractive profile, in which each step height is individually defined, with no fixed pattern. The intraocular lens provides a better control of the luminous efficiency of each focal point, guaranteeing more flexibility and customization, being adaptable to the optical quality that the patient needs.

Claims

1. An intraocular lens comprising: an anterior surface, a posterior surface, and wherein on at least one of the anterior or posterior surfaces a diffractive profile is formed, said diffractive profile providing for at least two diffractive focal points and comprising a non-apodized kinoform diffractive profile with equal area, wherein said diffractive profile has a plurality of steps with corresponding steps heights, each step height being individually defined, the first step height being between 0.30 μm and 4.5 μm, each subsequent step height being defined as a percentage of the step height of the immediate previous step.

2. Intraocular lens, in accordance with claim 1, wherein the diffractive profile provides for three diffractive focal points.

3. Intraocular lens, in accordance with claim 1, wherein the diffractive profile provides for four diffractive focal points.

4. Intraocular lens, in accordance with claim 1, wherein the diffractive profile provides for a focal region characterized as extended depth-of-focus.

5. Intraocular lens, in accordance with claim 1, wherein the second step height varies from 40 to 100% of the first step height.

6. Intraocular lens, in accordance with claim 1, wherein the third step height varies from 120 to 200% of the second step height.

7. Intraocular lens, in accordance with claim 1, wherein the fourth step height varies from 20 to 80% of the third step height.

8. Intraocular lens, in accordance with claim 1, wherein the fifth step height varies from 110 to 400% of the fourth step height.

9. Intraocular lens, in accordance with claim 1, wherein the sixth step height varies from 20 to 120% of the fifth step height.

10. Intraocular lens, in accordance with claim 1, wherein the seventh step height varies from 100 to 380% of the sixth step height.

11. Intraocular lens, in accordance with claim 1, wherein the eighth step height varies from 5 to 80% of the seventh step height.

12. Intraocular lens, in accordance with claim 1, wherein the ninth step height varies from 190 to 660% of the eighth step height.

13. Intraocular lens, in accordance with claim 1, wherein the second step height varies from 220 to 280% of the first step height.

14. Intraocular lens, in accordance with claim 1, wherein the third step height varies from 20 to 80% of the second step height.

15. Intraocular lens, in accordance with claim 1, wherein the fourth step height varies from 220 to 280% of the third step height.

16. Intraocular lens, in accordance with claim 1, wherein the fifth step height varies from 5 to 80% of the fourth step height.

17. Intraocular lens, in accordance with claim 1, wherein the sixth step height varies from 140 to 590% of the fifth step height.

18. Intraocular lens, in accordance with claim 1, wherein the seventh step height varies from 20 to 90% of the sixth step height.

19. Intraocular lens, in accordance with claim 1, wherein the eighth step height varies from 90 to 250% of the seventh step height.

20. Intraocular lens, in accordance with claim 1, wherein the ninth step height varies from 10 to 100% of the eighth step height.

21. Intraocular lens, in accordance with claim 1, wherein the total number (n) of steps of the diffractive profile varies from 4 to 43.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The present invention will be described in detail through the figures below, wherein:

(2) FIG. 1 is a generic representation of the basic components of an intraocular lens, in accordance with the state of the art.

(3) FIG. 2 is, a generic representation of the working principle of a diffractive intraocular lens, in accordance with the state of the art.

(4) FIG. 3 is a representation of an intraocular lens of the state of the art, which diffractive steps have constant height.

(5) FIG. 4 is a representation of an intraocular lens of the state of the art, which diffractive steps are apodized, with decreasing step heights.

(6) FIG. 5 is a representation of an intraocular lens of the state of the art, which diffractive steps have alternating step heights.

(7) FIGS. 6 and 7 are a representation of an intraocular lens of the state of the art, which combine to apodized diffractive profiles, to create a diffractive structure with alternately and gradually smaller steps.

(8) FIG. 8 is a representation of the intraocular lens in accordance with present invention, wherein each step height is individually defined.

DETAILED DESCRIPTION OF THE INVENTION

(9) In accordance with the schematic figures mentioned above, some examples of the possible embodiments of the present invention will be described in more details below but a in merely exemplificative and not limitative manner, since the object of the present invention can comprise different details and structural and dimensional aspects without however departing from the desired scope of protection.

(10) Hence, the present invention refers to an intraocular lens based on a diffractive profile (10) in which each step (20, 2n) has been optimized individually. Such an approach causes each diffractive step (20, 2n) to have a different height without following an apodized pattern and without alternating the height of the steps (20, 2n) along the diffractive profile as shown in the prior art disclosed in FIGS. 1 to 7.

(11) In other words, the distribution of heights of the steps (20, 2n) along the diffractive profile (10) is random, so that no pattern of alternation or apodization of the steps (20, 2n) is followed.

(12) In view of this, the intraocular lens of the present invention comprises an anterior surface and a posterior surface. On at least one of the anterior or posterior surfaces, a diffractive profile (10) is formed.

(13) Said diffractive profile (10) provides for at least two diffractive focal points, but preferably provide for three or four focal points. The diffractive profile (10) can also provide for a focal region characterized as extended depth-of-focus.

(14) Said diffractive profile (10) has a plurality of steps (20, 2n) with corresponding steps heights, each step height being individually defined, without any pattern, either constant, or apodized/alternate.

(15) The first step (20, 21) height, that is, the height of the step that is closer to the center of the anterior or posterior surface of the intraocular lens, is defined between 0.30 μm and 4.5 μm.

(16) Each subsequent step height is defined as a percentage of the step height of the immediate previous step.

(17) In other words, the height of the diffractive steps (20, 2n) is optimized individually, and there is an interdependence between pairs of steps starting from the first step (20, 21).

(18) In this sense, the second step (20, 22) height is optimized within a range, which is a percentage of the height of the first step (20, 21); the third step (20, 23) is optimized within a range, which is a percentage of the height of the second step (20, 22) and so on.

(19) In a particular advantageous embodiment, the second step (20, 22) height varies from 40 to 100% of the first step (20, 21) height; the third step (20, 23) height varies from 120 to 200% of the second step (20, 22) height; the fourth step (20, 24) height varies from 20 to 80% of the third step (20, 23) height; the fifth step (20, 25) height varies from 110 to 400% of the fourth step (20, 24) height; the sixth step (20, 26) height varies from 20 to 120% of the fifth step (20, 25) height; the seventh step (20, 27) height varies from 100 to 380% of the sixth step (20, 26) height; the eighth step (20, 28) height varies from 5 to 80% of the seventh step (20, 27) height; and the ninth step (20, 29) height varies from 190 to 660% of the eighth step (20, 28) height.

(20) In another particular advantageous embodiment, the second step (20, 22) height varies from 220 to 280% of the first step (20, 21) height; the third step (20, 23) height varies from 20 to 80% of the second step (20, 22) height; the fourth step (20, 24) height varies from 220 to 280% of the third step (20, 23) height; the fifth step (20, 25) height varies from 5 to 80% of the fourth step (20, 24) height; the sixth step (20, 26) height varies from 140 to 590% of the fifth step (20, 25) height; the seventh step (20, 27) height varies from 20 to 90% of the sixth step (20, 26) height; the eighth step (20, 28) height varies from 90 to 250% of the seventh step (20, 27) height; and the ninth step (20, 29) height varies from 10 to 100% of the eighth step (20, 28) height.

(21) Preferably, the total number (n) of steps (20, 2n) of the diffractive profile (10) varies from 4 to 43.

(22) In relation to the structure of the intraocular lens itself, the anterior and posterior surfaces preferably present convex curvatures, one being refractive and the other diffractive or hybrid (diffractive part and refractive part).

(23) Each of the surfaces may be spherical or aspherical. The diffractive profile (10) is able to create three foci based on the diffractive orders 0 (far focus), +1 (intermediate focus) and +2 (near focus), with additional between far and near focus, ranging from +1 D to +4 D.

(24) The shape of the diffractive steps (20, 2n) preferably follows a kinoform pattern.

(25) As defined above, the intraocular lens of the present invention is capable of creating 2 (bifocal), 3 (trifocal) or 4 (quadrifocal) focal points or generate a depth of focus.

EXAMPLES

(26) Some examples of ranges of values for the step (20, 2n) heights of the diffractive profiles in accordance with present invention are presented below.

Example 1

(27) Models M1-M6 refer to trifocal intraocular lens described on Table 1. The total number (n) of steps (20, 2n) presented may vary according to the additional defined for the diffractive profile.

(28) In this example, the Step-2 refers to second step (20, 22), and its step height is defined as a percentage range from the first step (20, 21). Step-3 refers to the third step (20, 23), and its step height is defined as a percentage range from the second step (20, 22), and so on. In this particular example, the models M1-M6 comprise 17 steps.

(29) TABLE-US-00001 TABLE 1 ranges of values for the step heights of the diffractive profiles (10) for 6 models of intraocular lens in accordance with present invention. Models Step-2 Step-3 Step-4 Step-5 Step-6 Step-7 Step-8 Step-9 M1 40-80% 150-200% 20-60% 110-400% 20-100% 300-380% 10-60% 300-360% M2 40-100%  120-190% 20-80% 110-180% 40-120% 160-230% 10-50% 280-340% M3 40-80% 150-200% 20-60% 110-400% 20-100% 160-230% 10-60% 590-640% M4 40-100%  120-190% 20-80% 110-180% 40-120% 100-150% 20-80% 190-240% M5 40-80% 150-200% 20-60% 110-400% 20-100% 320-380%  5-30% 590-660% M6 40-100%  120-190% 20-80% 110-180% 40-120% 120-180% 20-80% 220-280% Models Step-10 Step-11 Step-12 Step-13 Step-14 Step-15 Step-16 Step-17 M1 10-60% 300-360% 20-70% 180-230%  20-80% 200-270% 20-70% 250-330% M2 30-80% 180-230% 10-70% 250-320%  20-70% 250-320% 15-70% 290-350% M3  5-30% 200-270% 20-80% 930-990% 120-180%   20-70% 20-70%  80-130% M4 30-90% 140-200% 20-80% 200-250%  10-70% 220-300% 10-60% 150-210% M5 20-80% 190-250%  5-70% 230-300%  10-70% 320-380%  5-40%  80-130% M6 30-90%  90-150% 20-80% 120-180%  20-80% 280-340% 50-110%   60-120%

Example 2

(30) Models M1-M3 refer to depth-of-focus intraocular lens described on Table 2. The total number (n) of steps (20, 2n) presented may vary according to the additional defined for the diffractive profile.

(31) In this example, the Step-2 refers to second step (20, 22), and its step height is defined as a percentage range of the first step (20, 21). Step-3 refers to the third step (20, 23), and its step height is defined as a percentage range of the second step (20, 22), and so on. In this particular example, the models M1-M3 comprise 9 steps.

(32) TABLE-US-00002 TABLE 2 ranges of values for the step heights of the diffractive profiles (10) for 3 models of intraocular lens in accordance with present invention. Models Step-2 Step-3 Step-4 Step-5 Step-6 Step-7 Step-8 Step-9 M1 220-280% 20-80% 220-280%  5-50% 520-590% 30-90%  90-150% 20-80% M2 220-280% 20-80% 220-280% 20-80% 140-200% 30-90% 180-250% 10-70% M3 220-280% 20-80% 220-280% 20-70% 150-210% 20-90% 150-200% 30-100% 

(33) It is important to point out that the description above only intends to describe in an exemplificative manner all the preferred embodiments of the intraocular lens of the present invention. Hence, as understood by a person skilled in the art, the invention contemplates several construction modifications, variations and combinations of the features exerting the same function in substantially the same form to arrive at the same results, which are within the scope of protection limited by the appended claims.