Artificial lens and design method thereof

Abstract

This solution belongs to the field of intraocular lenses, and specifically relates to an artificial lens, including a lens optical part and a support haptic, wherein the lens optical part is a central transparent light-guiding area; the support haptic is fixedly connected to the edge of the lens optical part, and the distances from the haptic vertex plane to the vertex of the back surface of the lens of products with different optical focal lengths of the lens are consistent, and the distances from the main plane of the lens to the vertex of the back surface of the lens are consistent. At the same time, its design method is also announced, which can quickly and accurately design an artificial lens. Compared with traditional artificial lenses, this solution can make the prediction of the position of the lens in the eye more accurate, provide doctors with more accurate various constants used for the selection of the optical focal length of the lens, and is more conducive to doctors selecting the optical focal length of the lens for patients.

Description

Technical Field

[0001] The present invention belongs to the field of intraocular lenses, and specifically relates to an artificial lens. Background Art

[0002] Artificial lenses have different optical power values, and doctors need to select the correct optical power for patients before surgery. Because each person's eyes are different, different patients need different degrees of artificial lenses. When people wear glasses, they can change the degree of the lenses to make the customer subjectively satisfied. However, artificial lenses are implanted inside the eye, so they cannot be achieved by "trying" and can only be "predicted" by certain methods.

[0003] There are many formulas for calculating the optical power of artificial lenses for patients. The key point in these formulas is to predict the position of the lens in the human eye after implantation. Manufacturers will provide some constants for predicting optical power based on the statistical results of the product's clinical usage data. These constants reflect the position of the lens in the eye after implantation.

[0004] If a manufacturer's intraocular lens has multiple optical powers, it is necessary to ensure that the constants of all optical powers are consistent, such as the A constant of the STK / T formula. At present, these constants are mainly obtained by collecting clinical data after the product is launched and performing reverse statistical analysis. This method has the following problems: for a newly launched product, it is difficult to obtain the correct usage constant due to the lack of clinical data; at the same time, there will inevitably be deviations between the individual and statistical analysis results of products with different optical powers.

[0005] At the same time, some manufacturers currently take these constants into consideration during the optical design process. The main method is to adjust the optical design of the front and back surfaces of the lens to ensure that the main plane of the lens remains constant relative to the edge of the lens, and fix the loop design to make the loops of products with different optical powers consistent. The loop will be compressed by the equator of the capsular bag connected to the ciliary muscle, and it is assumed that the compression will not cause the position of the optical zone to shift relative to the stretched state. However, since the position of the lens in the eye is not only related to the equator of the capsular bag connected to the ciliary muscle, but also the back surface of the lens will be squeezed by the posterior capsule of the capsular bag, the two combined effects will affect the position of the lens. The thickness of lenses with different optical powers is different, and the distance from the vertex of the back surface to the vertex plane of the loop is different. The posterior capsule compression is inconsistent, which will cause the high-power lens to be squeezed more significantly, which will cause the lens to move forward, so that the predicted position of the lens in the eye will deviate significantly from the actual position. Therefore, the current method will lead to the inability to accurately predict the position of the lens in the eye. The difference in the predicted position of the lens in the eye will lead to deviations in the lens optical power selected by the doctor for the patient, thereby affecting the visual quality of the patient after surgery.

[0006] Therefore, there is an urgent need for an intraocular lens with different optical powers that has the same constant and can ensure the accuracy of the predicted position in the eye, so as to obtain an intraocular lens that is helpful for doctors to select the optical power of the lens for patients. Summary of the invention

[0007] This solution provides an artificial lens to make the prediction of the position of the lens in the eye more accurate, which is more conducive to doctors selecting the optical focal length of the lens for patients.

[0008] The principal plane described in this solution specifically refers to the second principal plane or the image-side principal plane.

[0009] In order to achieve the above-mentioned purpose, the present scheme provides an artificial lens, including a crystal optical part and a support haptic, wherein the crystal optical part is a central transparent light-guiding area; the support haptic is fixedly connected to the edge of the crystal optical part, the distance from the haptic vertex plane to the vertex of the back surface of the crystal of the lenses with different optical focal powers is consistent, and the distance from the main plane of the crystal to the vertex of the back surface of the crystal is consistent.

[0010] The principle and beneficial effect of this solution are: this solution not only ensures the influence of the constraint effect of the capsular bag equatorial structure on the position of the lens in the eye, but also eliminates the displacement of the lens in the eye caused by the inconsistent pressure of the posterior capsule of the capsular bag. This solution can make the prediction of the position of the lens in the eye more accurate, which is more conducive to doctors choosing the optical power of the lens for patients.

[0011] Further, the principal plane of the crystal is located between the apex of the rear surface and the apex of the front surface of the crystal or in front of the apex of the front surface.

[0012] Furthermore, another object of the present invention is to provide a method for designing an intraocular lens, comprising the following steps:

[0013] Step 1: Design the optical zone;

[0014] Through continuous iterative optimization of the curvature radius and aspheric coefficient in the optical design of the two optical surfaces of the crystal, the distance from the main plane of the crystal with different optical powers to the vertex of the rear surface of the crystal is made consistent; at the same time, the spherical aberration and optical power of the crystal are optimized until the design requirements are met;

[0015] Step 2: Design the loop area; by changing the size of the loop angle or the connection position between the loop and the edge of the optical part, the distance from the loop vertex plane to the back surface of the lens is made consistent.

[0016] Furthermore, the position of the principal plane of the crystal is obtained by using ray tracing in optical software, and then all crystals with different optical powers should be guaranteed to have the same d2 value, and d2 is a positive value.

[0017] Furthermore, Matlab design software is used to iteratively optimize the curvature radius and aspheric coefficient. Matlab software is easy to operate and provides accurate data.

[0018] Furthermore, we use design software such as ZEMAX to optimize the spherical aberration and optical power of the lens. ZEMAX software is easy to operate and provides accurate data. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic structural diagram of an embodiment of the present invention.

[0020] Figure 2 It is a schematic structural diagram of an embodiment of the present invention. DETAILED DESCRIPTION

[0021] The following is a further detailed description through specific implementation methods:

[0022] The reference numerals in the drawings of the specification include: cornea 10 , anterior capsule 20 , posterior capsule 30 , capsule equator 40 , lens 50 , support haptics 60 , haptic angle 70 , haptic vertex plane 81 .

[0023] As attached Figure 1 As shown, this is a schematic diagram of an artificial lens 50 in the eyeball. The artificial lens is fixed in the capsular bag, the optical posterior surface is close to or close to the posterior capsule 30, the haptic is supported in the capsule equator 40, and the outermost layer of the eyeball is the cornea 10.

[0024] The specific structure of the crystal is Figure 2 As shown, it mainly includes two parts, namely the crystal optical part and the support haptic 60. The crystal optical part is the central transparent light-guiding area, and the support haptic 60 is connected to the edge of the crystal optical part. The angle between the optical surface edge plane of the crystal optical part and the support haptic 60 is the haptic angle 70. The distance from the haptic vertex plane 81 of the crystal to the vertex of the back surface of the crystal is consistent, and the distance from the main plane of the crystal to the vertex of the back surface of the crystal is consistent.

[0025] The main plane of the crystal is located between the apex of the rear surface and the apex of the front surface of the crystal, but it is also possible to arrange it before the apex of the front surface.

[0026] The specific design method of the intraocular lens 50 includes:

[0027] Step 1: Design the optical area:

[0028] The curvature radius and aspheric coefficients in the optical design of the two optical surfaces of the crystal are continuously optimized by using MATLAB design software, so that the distance from the main plane of the crystal to the vertex of the rear surface of the crystal is consistent; at the same time, the spherical aberration and optical power of the crystal are optimized using ZEMAX design software until the design requirements are met; then all crystals with different optical powers should be guaranteed to have the same D2 value, and D2 is a positive value. In this embodiment, the D2 value is 0.324 mm

[0029] Step 2, design the loop area;

[0030] By changing the size of the loop angle 70 or the connection position between the loop and the optical part, the distance from the loop vertex plane 81 to the back surface of the lens is made consistent, that is, H0 and d p The sum of the distances is equal, thereby obtaining an artificial lens 50.

[0031] The material refractive index is selected as 1.520, the product optical diameter is 6.0mm, the product is a spherical lens, and the H value is set to 0.40mm. According to the above method, three intraocular lenses 50 with different optical focal lengths are designed, and the specific parameters are as follows:

[0032]

[0033]

[0034] The d2 values ​​of the intraocular lenses 50 of different optical powers are the same, all of which are 0.324 mm, ensuring that the distance from the main plane of the lens to the vertex of the back surface of the lens is consistent. At the same time, the haptic angles 70 of different optical powers are different. In this solution, the haptic angle 70 corresponding to the 10.0D optical power is the smallest, and the haptic angle 70 corresponding to the 30.0D optical power is the largest. By adjusting the haptic angle 70, the distance from the haptic vertex plane 81 of the lens to the vertex of the back surface of the lens is ensured to be consistent.

[0035] This design not only ensures the influence of the capsular bag equatorial structure on the position of the lens in the eye, but also eliminates the displacement of the lens in the eye caused by the inconsistent pressure of the posterior capsule 30 of the capsular bag. Compared with the traditional intraocular lens 50, this solution can make the prediction of the position of the lens in the eye more accurate, which is more conducive to doctors choosing the optical power of the lens for patients.

[0036] The above is only an embodiment of the present invention, and the common knowledge such as the known specific structure and characteristics in the scheme is not described in detail here. It should be pointed out that for those skilled in the art, several deformations and improvements can be made without departing from the structure of the present invention, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A method for designing an artificial lens, characterized in that: The intraocular lens comprises an optical part of the lens and a support haptic, wherein the optical part of the lens is a central transparent light-guiding area; the support haptic is fixedly connected to the edge of the optical part of the lens, the distance from the haptic vertex plane of the lens to the vertex of the rear surface of the lens is consistent, and the distance from the main plane of the lens to the vertex of the rear surface of the lens is consistent, and the rear surface of the lens is the optical surface close to the posterior capsule; by changing the size of the haptic angle or the connection position between the haptic and the edge of the optical part, the distance from the haptic vertex plane to the rear surface of the lens is consistent; the main plane of the lens is located between the vertex of the rear surface of the lens and the vertex of the front surface or in front of the vertex of the front surface; The design method of the intraocular lens comprises the following steps: Step 1: Design the optical zone; Through continuous iterative optimization of the curvature radius and aspheric coefficient in the optical design of the two optical surfaces of the crystal, the distance from the main plane of the crystal to the vertex of the rear surface of the crystal is made consistent; at the same time, the spherical aberration and optical power of the crystal are optimized until the design requirements are met; Step 2: Design the loop area; by changing the size of the loop angle, the distance from the loop vertex plane to the vertex of the rear surface of the lens is made consistent; The position of the principal plane of the crystal is obtained by using ray tracing in optical software, and all crystals with different optical powers should be guaranteed to have the same d2 value, and d2 is a positive value, that is, a positive value indicates that the principal plane is located before the vertex of the back surface.

2. The method for designing an intraocular lens according to claim 1, characterized in that: Matlab design software is used to continuously iterate and optimize the curvature radius and aspheric coefficients.

3. The method for designing an intraocular lens according to claim 1, characterized in that: Zemax design software is used to optimize the lens spherical aberration and optical power.

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