Four-axis asymmetric corneal correction lens and preparation method

Abstract

To provide a four-axis asymmetric corneal correction leans and a preparation method.SOLUTION: In a four-axis asymmetric corneal correction lens, four meridians 35, 36, 37, 38 of a lens body are determined based on an average arrow height value within a specific annular zone on a cornea, an alignment curve area of the four meridians of the lens body are divided into four annular sector areas 31, 32, 33, 34, a different curvature is assigned to each meridian, and subsequently, separate curvature designs are performed relative to the curved surfaces of the four annular sector areas. This allows the corneal correction lens to better fit a wearer's cornea, achieving better compatibility and helping to provide accurate, personalized fitting to various asymmetric and irregular corneas.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to the technical field of orthokeratology lenses, and in particular to a four-axis asymmetric orthokeratology lens and a preparation method thereof. [Background technology]

[0002] An orthokeratology lens is a rigid gas-permeable lens used in orthokeratology, and generally has four curve areas: a base curve area, a reverse curve area, an alignment curve area, and a peripheral curve area. The function of the alignment curve area is to ensure that the lens is well positioned at the center of the cornea to achieve an ideal correction effect. Most of the alignment curve areas of conventional lenses are rotationally symmetric spherical geometric structures or geometrically symmetric double curved geometric structures, which cannot properly fit most asymmetric and irregular anterior corneal surfaces, resulting in lens deviation and potential safety hazards.

[0003] The existing Chinese invention patent application publication no. CN114740635A discloses a four-quadrant asymmetric orthocorneal lens, which uses a four-quadrant asymmetric design for the alignment curve area. However, because the area covering the cornea within the four quadrants of the orthocorneal lens is uniform and the four meridians dividing the four quadrants are perpendicular to each other, the inner surface of the orthocorneal lens that transitions between the four quadrants cannot fit well to the anterior surface of the cornea. In addition, the existing Chinese invention patent application publication no. CN117192806A discloses an atypical four-quadrant asymmetric orthocorneal lens, which uses an atypical four-quadrant asymmetric design in the alignment curve area, but the division of the meridians is fixed and not based on the actual corneal shape, and similarly, the inner surface of the orthocorneal lens that transitions between the meridians cannot fit well to the anterior surface of the cornea. It is clear that all of the above-mentioned existing orthocorneal lenses have the problem that the effect of preventing and suppressing myopia is poor due to lens deviation, and it is not possible to obtain an effective effect of preventing and suppressing myopia.

[0004] Therefore, in order to solve the above-mentioned problems, the present invention proposes a four-axis asymmetric orthokeratological lens and a preparation method that can better fit the wearer's cornea. Summary of the Invention

[0005] To solve the above-mentioned problems, the present invention provides a four-axis asymmetric orthokeratological lens and a preparation method.

[0006] According to one object of the present invention, there is provided a four-axis asymmetric orthocorneal lens, the four-axis asymmetric orthocorneal lens comprising: The lens comprises a base curve area, and a reverse curve area, an alignment curve area, and a peripheral curve area, which are successively formed in this order from the periphery of the base curve area toward the outside, The orthodontic lens has several meridians arranged therein, and the portions of each meridian on the inner surface of the alignment curve area and the horizontal plane of the apex of the inner surface of the orthodontic lens all have mean arrow height values. Of all the meridians on the orthodontic lens, the one meridian with the smallest mean arrow height value is the flattest meridian, and the one meridian with the largest mean arrow height value is the steepest meridian, and all the flattest Among the meridians that form an included angle of 90° or more with the prime meridian, the one with the smallest mean arrow height is the next flattest meridian, and among the meridians that form an included angle of 90° or more with all the steepest meridians, the one with the largest mean arrow height is the next steepest meridian, and the alignment curve area is divided into four circular sector areas by the flattest meridian, the next flattest meridian, the steepest meridian, and the next steepest meridian. The center of the base curve area corresponds to the center of the cornea, and the area on the cornea corresponding to the alignment curve area is defined as a specific annular zone area. The curvature distribution of the inner surface in the alignment curve area where the flattest meridian of the orthocorneal lens is located is consistent with the curvature distribution of the outer surface in the specific annular zone area where the flattest meridian of the cornea is located. The curvature distribution of the inner surface in the alignment curve area where the next flattened meridian of the orthocorneal lens is located matches the curvature distribution of the outer surface in the specific annular zone area where the next flattened meridian of the cornea is located. The curvature distribution of the inner surface in the range of the alignment curve area where the steepest meridian of the orthocorneal lens is located is consistent with the curvature distribution of the outer surface in the range of the specific annular zone area where the steepest meridian of the cornea is located. The curvature distribution of the inner surface in the alignment curve area where the next steepest meridian of the orthocorneal lens is located is consistent with the curvature distribution of the outer surface in the specific annular zone area where the next steepest meridian of the cornea is located.

[0007] Preferably, there is a gradual transition between adjacent annular sectors, and the curvature of each annular sector transitions gradually between the edges of the two meridians that divide the annular sector.

[0008] Preferably, in the orthocorneal lens, when the difference in the mean arrow height between adjacent meridians is greater than 45 um, the compartment meridian of the orthocorneal lens is disposed between the adjacent meridians; The dividing meridian of the orthocorneal lens divides the annular sector area formed by adjacent meridians into two partial annular sector areas; The curvature distribution of the inner surface within the alignment curve area where the segment meridian of the orthocorneal lens is located is consistent with the curvature distribution of the anterior surface of the cornea within the specific annular zone area where the segment meridian of the cornea is located.

[0009] Preferably, the segment meridian of the orthokeratological lens is the one meridian whose mean arrow height is the middle value among all the meridians within the annular sector area in which the segment meridian is located.

[0010] Preferably, two partial annular sectors within an annular sector are connected to each other so as to form a gradual transition, and the inner surfaces of the two partial annular sectors form a smoothly curved surface.

[0011] Preferably, the curvature of the annular sector transitions gradually from the edge where the two meridians dividing the annular sector are located to the edge where the dividing meridian within the annular sector is located.

[0012] The present invention further provides a method for preparing a four-axis asymmetric orthocorneal lens, the method for preparing a four-axis asymmetric orthocorneal lens comprising: Step S10 of providing a lens body to be adjusted, the lens body having a base curve area, and a reverse curve area, an alignment curve area, and a peripheral curve area formed successively from the periphery of the base curve area outward; Step S20 of dividing the alignment curve area into four circular sector areas via the flattest meridian, the next flattest meridian, the steepest meridian, and the next steepest meridian, each of which passes through the center of the base curve area; and the steps of determining the flattest meridian, the next flattest meridian, the steepest meridian, and the next steepest meridian include: a step S21 of obtaining several meridians of the cornea; Step S22: matching the center of the base curve area of ​​the lens body to be adjusted with the center of the cornea, and selecting an area corresponding to a specific annular zone area on the cornea as an alignment curve area of ​​the lens body to be adjusted; Step S23: Calculating the average arrow height from the anterior surface of the cornea to the horizontal plane of the corneal vertex within a specific annular zone area where each meridian on the cornea is located; Step S24 of acquiring the flattest corneal meridian and the steepest corneal meridian, in which, among all the corneal meridians, the flattest corneal meridian is the one meridian with the smallest mean arrow height value, and the steepest corneal meridian is the one meridian with the largest mean arrow height value; Step S25 of acquiring the next flattest meridian and the next steepest meridian of the cornea, in which the next flattest meridian of the cornea is the one meridian with the smallest mean arrow height among the meridians that form an angle of 90° or more with the flattest meridian of the cornea, and the next steepest meridian of the cornea is the one meridian with the largest mean arrow height among the meridians that form an angle of 90° or more with the steepest meridian of the cornea; and step S20. Step S30 of obtaining an orthokeratological lens by adjusting the curvature distribution of the inner surface in a range of an alignment curve area where the flattest meridian of the lens body to be adjusted, the next flattest meridian of the lens body to be adjusted, the steepest meridian of the lens body to be adjusted, and the next steepest meridian of the lens body to be adjusted are located, based on the curvature distribution of the anterior surface of the cornea in a range of a specific annular zone area where the flattest meridian of the cornea, the next flattest meridian of the cornea, the steepest meridian of the cornea, and the next steepest meridian of the cornea are located, wherein the orthokeratological lens adjusts the curvature distribution of the inner surface in a range of an alignment curve area where the flattest meridian of the orthokeratological lens is located to a curvature distribution of the outer surface in a range of a specific annular zone area where the flattest meridian of the cornea is located. and step S30, wherein the curvature distribution of the inner surface in the alignment curve area where the next flattest meridian of the orthodontic lens is located matches the curvature distribution of the outer surface in the specific annular zone area where the next flattest meridian of the cornea is located, the curvature distribution of the inner surface in the alignment curve area where the steepest meridian of the orthodontic lens is located matches the curvature distribution of the outer surface in the specific annular zone area where the steepest meridian of the cornea is located, and the curvature distribution of the inner surface in the alignment curve area where the next steepest meridian of the orthodontic lens is located matches the curvature distribution of the outer surface in the specific annular zone area where the next steepest meridian of the cornea is located, and a gradual transition process is performed between adjacent annular sector areas.

[0013] Preferably, the method for preparing the four-axis asymmetric orthocorneal lens comprises: Step S40: obtaining a corneal meridian, the corneal meridian being a meridian located between adjacent meridians when the difference in mean arrow height between the adjacent meridians on the cornea is greater than 45 um, and the corneal meridian divides the annular sector area formed by the adjacent meridians into two partial annular sector areas; The method further includes a step S41 of obtaining an orthokeratological lens corresponding to adjusting the segment meridian of the adjusted lens body based on the curvature distribution of the anterior surface of the cornea in the range of the specific annular zone where the segment meridian of the cornea is located, wherein the orthokeratological lens makes the curvature distribution of the inner surface in the alignment curve area range where the segment meridian of the orthokeratological lens is located consistent with the curvature distribution of the outer surface of the cornea in the range of the specific annular zone where the segment meridian of the cornea is located, and performs a gradual transition process between adjacent partial annular sector areas.

[0014] Preferably, the dividing meridian of the orthocorneal lens is one meridian between two adjacent meridians whose mean arrow height is the middle value.

[0015] Preferably, the base curve area, the reverse curve area, the alignment curve area, and the peripheral curve area are integrally molded from the inside to the outside.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. The four-axis asymmetric orthocorneal lens determines four meridians of the lens body based on the average arrow height value within a specific annular zone on the cornea, with the flattest meridian corresponding to the flattest zone of the cornea, the next flattest meridian corresponding to the next flattest zone of the cornea, the steepest meridian corresponding to the steepest zone of the cornea, and the next steepest meridian corresponding to the next steepest zone of the cornea. The four meridians divide the alignment curve area of ​​the lens body into four annular sectors, and assign different curvatures to each meridian. Subsequently, different curvature designs are made for the curved surfaces of the four annular sectors, which allows the orthocorneal lens to better fit the wearer's cornea, achieve better compatibility, and help achieve accurate and personalized fitting for various asymmetric and irregular corneas. 2. In an annular sector area with a large span of average arrow height values, a division meridian is arranged so that the annular sector area with a large span of average arrow height values ​​can be subdivided into two partial annular sector areas, and the division meridian is determined by taking the median value of the average arrow height values ​​of all meridians within the annular sector area in which the division meridian is located, so that it can more accurately fit the surface shape of the patient's cornea, thereby making each annular sector area of ​​the alignment curve area of ​​the lens body better fit the patient's cornea, further improving compatibility with the cornea, effectively preventing deviation of the lens body, and optimizing the corrective effect on the cornea.

[0017] The present invention will be further described below in combination with the drawings and examples. [Brief explanation of the drawings]

[0018] [Figure 1] 1 is a schematic diagram of the overall structure of a four-axis asymmetric corrective corneal lens according to the present invention, viewed from a certain viewing angle. [Figure 2] 1 is a schematic diagram of the cross-sectional structure of a four-axis asymmetric corrective corneal lens according to the present invention, viewed from another viewing angle. [Figure 3] 1 is a schematic diagram of the flattest, steepest, next flattest, and next steepest meridians of a four-axis asymmetric orthokeratological lens according to the present invention. [Figure 4]1 is a schematic diagram of the arrow height calculation of one meridian of a four-axis asymmetric orthocorneal lens according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0019] The following description is intended to explain the present invention in detail so that those skilled in the art can practice the present invention. The preferred embodiments in the following description are merely illustrative, and other obvious modifications will occur to those skilled in the art. The basic principles of the present invention defined in the following description may be applied to other embodiments, variations, improvements, equivalents, and other technical forms without departing from the spirit and scope of the present invention.

[0020] Referring to FIG. 1-FIG. 2, the present invention provides a technical solution, namely, a four-axis asymmetric orthocorneal lens, which comprises: The lens body has a circular shape in plan view and an arc-shaped piece-like cross section, and the lens body has a base curve area 1, a reverse curve area 2, an alignment curve area 3, and a peripheral curve area 4, which are integrally molded from the inside to the outside, the base curve area 1 has an arc-shaped piece-like structure located in the central region of the lens body, the reverse curve area 2 has a narrow annular structure surrounding the base curve area 1, and the alignment curve area 3 has an arc-shaped piece-like structure surrounding the reverse curve area 2. The lens has a slightly wider annular structure surrounding the alignment curve area 3, the peripheral curve area 4 has a narrower annular structure surrounding the alignment curve area 3, the base curve area 1 is the central optical area and treatment zone mainly for flattening the corneal surface, the reverse curve area 2 collects tears in the center and encourages the lens base curve area 1 to flatten the center of the anterior surface of the cornea, the alignment curve area 3 fits to the cornea and fixes the lens, increasing the stability of the lens when worn, and the peripheral curve area 4 has a slightly curved edge to facilitate smooth tear exchange.

[0021] That is, the four-axis asymmetric orthocorneal lens comprises a base curve area 1, and a reverse curve area 2, an alignment curve area 3, and a peripheral curve area 4 which are formed continuously in this order from the periphery of the base curve area 1 outward.

[0022] In use, the center of the base curve area 1 corresponds to the center of the cornea, and the area where the cornea and the alignment curve area 3 correspond is defined as a specific annular zone area. Correlation data of multiple meridians of the cornea is obtained, and the multiple meridians of the cornea can divide the cornea into multiple equal fan-shaped areas. Within the specific annular zone area, the area between the anterior surface of the cornea and the horizontal plane of the apex of the cornea has a mean arrow height value. Of all the meridians on the cornea, the one meridian with the smallest mean arrow height value is the flattest meridian of the cornea, and the mean arrow height value is The largest meridian is the steepest corneal meridian, the meridian that forms an angle of 90° or more with the flattest meridian and has the smallest mean sagittal height is the next flattest corneal meridian, and the meridian that forms an angle of 90° or more with the steepest meridian and has the largest mean sagittal height is the next steepest corneal meridian, and the specific annular zone is divided into four corneal annular sector areas by the flattest corneal meridian, the next flattest corneal meridian, the steepest corneal meridian, and the next steepest corneal meridian. Similarly, the orthodontic lens has several meridians arranged thereon, and the portions of each meridian on the inner surface of the alignment curve area 3 and the horizontal plane of the apex of the inner surface of the orthodontic lens all have mean arrow heights. Of all the meridians on the orthodontic lens, the one with the smallest mean arrow height is the flattest meridian 6 of the orthodontic lens, the one with the largest mean arrow height is the steepest meridian 7 of the orthodontic lens, and the meridian that forms an included angle of 90° or more with the flattest meridian 6 of all the orthodontic lenses. Among these, the meridian with the smallest mean arrow height value is the next flattest meridian 8 for the orthodontic lens, and among the meridians that form an included angle of 90° or more with the steepest meridian 7 for all orthodontic lenses, the meridian with the largest mean arrow height value is the next steepest meridian 9 for the orthodontic lens, and alignment curve area 3 is divided into four annular fan-shaped areas by the flattest meridian 6 for the orthodontic lens, the next flattest meridian 8 for the orthodontic lens, the steepest meridian 7 for the orthodontic lens, and the next steepest meridian 9 for the orthodontic lens. The curvature distribution of the inner surface in the alignment curve area where the flattest meridian 6 of the orthocorneal lens is located is consistent with the curvature distribution of the outer surface in the specific annular zone area where the flattest meridian of the cornea is located; The curvature distribution of the inner surface in the alignment curve area where the next flattened meridian 8 of the orthocorneal lens is located is consistent with the curvature distribution of the outer surface in the specific annular zone area where the next flattened meridian of the cornea is located; The curvature distribution of the inner surface in the alignment curve area where the steepest meridian 7 of the orthocorneal lens is located is consistent with the curvature distribution of the outer surface in the specific annular zone area where the steepest meridian of the cornea is located; The curvature distribution of the inner surface in the alignment curve area where the next steepest meridian 9 of the orthocorneal lens is located is consistent with the curvature distribution of the outer surface in the specific annular zone area where the next steepest meridian of the cornea is located.

[0023] Preferably, in the orthokeratric lens, there is a gradual transition between adjacent annular sector areas, and the inner surfaces of adjacent annular sector areas form a smooth curved surface.

[0024] Specifically, referring to FIG. 1 , in the orthocorneal lens, the four annular sector areas are a first annular sector area 31, a second annular sector area 32, a third annular sector area 33, and a fourth annular sector area 34, respectively; the first annular sector area 31 and the second annular sector area 32 are separated by the steepest meridian 7 of the orthocorneal lens, and the first annular sector area 31 and the second annular sector area 32 are connected to each other in a gradual transition; the inner surfaces of the first annular sector area 31 and the second annular sector area 32 form a smooth curved surface; the second annular sector area 32 and the third annular sector area 33 are separated by the next flattest meridian 8 of the orthocorneal lens, and the second annular sector area 32 and the third annular sector area 33 are connected to each other in a gradual transition; the inner surfaces of the second annular sector area 32 and the third annular sector area 33 form a smoothly curved surface; the third annular sector area 33 and the fourth annular sector area 34 are separated by the next steepest meridian 9 of the orthokeratological lens and are connected to each other in a gradual transition; the inner surfaces of the third annular sector area 33 and the fourth annular sector area 34 form a smoothly curved surface; the fourth annular sector area 34 and the first annular sector area 31 are separated by the flattest meridian 6 of the orthokeratological lens and are connected to each other in a gradual transition; the inner surfaces of the fourth annular sector area 34 and the first annular sector area 31 form a smoothly curved surface.

[0025] Referring to FIG. 3, the edges on both sides of the inner surface of the alignment curved area 3 in the radial direction are curved area edge c and curved area edge d, respectively. The flattest meridian 6 intersects with curved area edge c to form intersection point a, and the flattest meridian 6 intersects with curved area edge d to form intersection point B. The intersection points A and B and all points between them of the flattest meridian 6 on the inner surface of the lens body constitute a set, which is called an arc segment AB. This set is the flattest meridian on the inner surface of the alignment curved area 3. As can be inferred by a person skilled in the art, the next flattest meridian 8 portion of the inner surface of the alignment curve area 3, the steepest meridian 7 portion of the inner surface of the alignment curve area 3, and the next steepest meridian 9 portion of the inner surface of the alignment curve area 3 mentioned in the above solution are determined, as well as the flattest meridian portion of the front surface of the specific annular band area, the next flattest meridian portion of the front surface of the specific annular band area, the steepest meridian portion of the front surface of the specific annular band area, and the next steepest meridian portion of the front surface of the specific annular band area.

[0026] The edges of the curved area are the edges on both sides of the inner surface of the alignment curved area 3, and the flattest meridian 6 on the inner surface of the alignment curved area 3 is the line segment obtained by cutting the flattest meridian 6 on the inner surface of the orthodontic lens with the two curved area edges; in other words, the longitudinal ends of the flattest meridian 6 on the inner surface of the alignment curved area 3 are each located on one of the curved area edges.

[0027] It is also necessary to explain that the corneal meridian is a longitude line on the cornea, which passes through the center of the cornea and both ends of the meridian reach the corneal limbus, the meridian of an orthodontic lens is a longitude line on the orthodontic lens that corresponds to the corneal meridian when the orthodontic lens is placed on the anterior surface of the cornea, and the arrow height is a general concept in geometry, and in orthodontic lenses and corneas, the arrow height can help understand the design features of the lens body, such as the thickness distribution, curvature, etc. of the lens body. The arrow height value refers to the vertical distance between the reference plane and a specified point on the lens body or corneal surface. Specifically, to calculate the average arrow height value on the cornea and lens body, a number of measurement points are equally spaced on the anterior surface of a specific annular zone where each meridian on the cornea is located, the vertical distances between each measurement point and the horizontal plane where the vertex of the anterior surface of the cornea is located are summed up, and then this sum is divided by the number of measurement points. The average arrow height value on the anterior surface of the specific annular zone where each meridian on the cornea is located is obtained by equally spaced on the inner surface of the alignment curve area 3 where each meridian on the lens body is located, the vertical distances between each measurement point and the horizontal plane where the vertex of the inner surface of the lens body is located are summed up, and then this sum is divided by the number of measurement points. The average arrow height value on the inner surface of the alignment curve area 3 where each meridian on the lens body is located can be obtained. For orthocorneal lenses, the distance from the lens body surface to a specified reference plane can be obtained using an optical microscope, interferometer, or the like. In one embodiment of the present invention, referring to FIG. 4, the lens body has one meridian x, and the lens body has a vertex horizontal plane y, and five measurement points, namely N1, N2, N3, N4, and N5, are provided on the inner surface of the alignment curve area 3 of the meridian x. The vertical distances from N1, N2, N3, N4, and N5 to the vertex horizontal plane y of the lens body are measured, added up, and then divided by the number of measurement points, 5, to obtain the average arrow height value on the inner surface of the alignment curve area 3 of the lens body where the meridian x is located.

[0028] The four-axis asymmetric orthodontic lens determines four meridians of the lens body based on the average arrow height value within a specific annular zone on the cornea, the flattest meridian 6 of the orthodontic lens corresponds to the flattest zone of the cornea, the next flattest meridian 8 of the orthodontic lens corresponds to the next flattest zone of the cornea, the steepest meridian 7 of the orthodontic lens corresponds to the steepest zone of the cornea, and the next steepest meridian 9 of the orthodontic lens corresponds to the next steepest zone of the cornea, the four meridians of the orthodontic lens divide the alignment curve area 3 of the lens body into four annular sectors, and allocate different curvatures to each meridian, and then design different curvatures relative to the curved surfaces of the four annular sectors, so that the orthodontic lens can better fit the cornea of ​​the wearer and achieve better compatibility; It helps to provide accurate individualized fitting to a variety of asymmetric and irregular corneas.

[0029] Preferably, the base curve area 1, the reverse curve area 2, the alignment curve area 3, and the peripheral curve area 4 are integrally molded from the inside to the outside.

[0030] It should be noted that the center of the cornea in this solution corresponds to the center of the base curve area 5, and therefore the flattest meridian 6 of the orthodontic lens, the next flattest meridian 8 of the orthodontic lens, the steepest meridian 7 of the orthodontic lens, and the next steepest meridian 9 of the orthodontic lens all pass through the center of the base curve area 1.

[0031] Preferably, in the orthokeratology lens, the curvature of each annular sector transitions gradually between the edges where the two meridians that divide the annular sector lie.

[0032] In one embodiment of the invention, the curvature of the first annular sector area 31 increases uniformly directly from the edge where the flattest meridian 6 of the orthokeratology lens is located to the edge where the steepest meridian 7 of the orthokeratology lens is located. The curvature of the second annular sector area 32 tapers uniformly from the edge where the steepest meridian 7 of the orthokeratological lens is located directly to the edge where the next flattest meridian 8 of the orthokeratological lens is located. The curvature of the third annular sector area 33 increases uniformly from the edge where the next flattest meridian 8 of the orthokeratology lens is located directly to the edge where the next steepest meridian 9 of the orthokeratology lens is located. The curvature of the fourth annular sector area 34 tapers uniformly from the edge where the next steepest meridian 9 of the orthokeratological lens is located directly to the edge where the flattest meridian 6 of the orthokeratological lens is located.

[0033] In order to further improve the compatibility with the cornea, effectively prevent the lens body from shifting, and optimize the corrective effect on the cornea, when the difference in mean arrow height between adjacent meridians in the orthodontic lens is greater than 45 um, the segment meridian of the orthodontic lens is positioned between the adjacent meridians, and the segment meridian of the orthodontic lens divides the annular fan area formed by the adjacent meridians into two partial annular fan areas, and the curvature distribution of the inner surface in the range of alignment curve area 3 where the segment meridian of the orthodontic lens is located is consistent with the curvature distribution of the anterior surface of the cornea in the range of the specific annular zone where the segment meridian of the cornea is located.

[0034] Specifically, if the mean difference in arrow height between the flattest meridian of the cornea and the steepest meridian of the cornea is greater than 45 μm, imaginary corneal meridian I is placed between the flattest meridian of the cornea and the steepest meridian of the cornea. If the mean difference in arrow height between the steepest meridian of the cornea and the next flattest meridian of the cornea is greater than 45 μm, imaginary corneal meridian II is placed between the steepest meridian of the cornea and the next flattest meridian of the cornea orthodontic lens. If the mean difference in arrow height between the next flattest meridian of the cornea and the next steepest meridian of the cornea is greater than 45 μm, imaginary corneal meridian III is placed between the next flattest meridian of the cornea and the next steepest meridian of the cornea. If the mean difference in arrow height between the next steepest corneal meridian and the flattest corneal meridian is greater than 45 um, imaginary corneal meridian IV is placed between the next steepest corneal meridian and the flattest corneal meridian.

[0035] Correspondingly, if the average arrow height difference between the flattest meridian 6 of the orthodontic lens and the steepest meridian 7 of the orthodontic lens is greater than 45 um, the division meridian I35 of the orthodontic lens is positioned between the flattest meridian 6 of the orthodontic lens and the steepest meridian 7 of the orthodontic lens, and the division meridian I35 of the orthodontic lens divides the first annular sector area 31 into two partial annular sector areas, and the two partial annular sector areas are connected in a gradual transition; otherwise, the division meridian I35 of the orthodontic lens is not positioned. If the average arrow height difference between the steepest meridian 7 of the orthodontic lens and the next flattest meridian 8 of the orthodontic lens is greater than 45 μm, the orthodontic lens's division meridian II 36 is positioned between the steepest meridian 7 of the orthodontic lens and the next flattest meridian 8 of the orthodontic lens, and the orthodontic lens' division meridian II 36 divides the second annular sector area 32 into two partial annular sector areas, and the two partial annular sector areas are connected in a gradual transition; otherwise, the orthodontic lens' division meridian II 36 is not positioned. If the average arrow height difference between the next flattest meridian 8 of the orthodontic lens and the next steepest meridian 9 of the orthodontic lens is greater than 45 μm, the orthodontic lens's division meridian III37 is positioned between the next flattest meridian 8 of the orthodontic lens and the next steepest meridian 9 of the orthodontic lens, and the orthodontic lens' division meridian III37 divides the third annular sector area 33 into two partial annular sector areas, and the two partial annular sector areas are connected by a gradual transition; otherwise, the orthodontic lens' division meridian III37 is not positioned. If the average arrow height difference between the next steepest meridian 9 of the orthodontic lens and the flattest meridian 6 of the orthodontic lens is greater than 45 um, the segment meridian IV38 of the orthodontic lens is positioned between the next steepest meridian 9 of the orthodontic lens and the flattest meridian 6 of the orthodontic lens, and the segment meridian IV38 of the orthodontic lens divides the fourth annular sector area 34 into two partial annular sector areas, and the two partial annular sector areas are connected in a gradual transition; otherwise, the segment meridian IV38 of the orthodontic lens is not positioned.

[0036] The curvature distribution of the inner surface in the alignment curve area 3 where the segment meridian I35 of the corrective lens is located is consistent with the curvature distribution of the anterior surface of the cornea in the specific annular zone where the segment meridian I of the cornea is located. The curvature distribution of the inner surface in the alignment curve area 3 where the segment meridian II 36 of the orthocorneal lens is located is consistent with the curvature distribution of the anterior surface of the cornea in the specific annular zone where the segment meridian II of the cornea is located. The curvature distribution of the inner surface in the alignment curve area 3 where the segment meridian III 37 of the corrective lens is located is consistent with the curvature distribution of the anterior surface of the cornea in the specific annular zone area where the segment meridian III of the cornea is located. The curvature distribution of the inner surface in the alignment curve area 3 where the segment meridian IV38 of the corrective lens is located is consistent with the curvature distribution of the anterior surface of the cornea in the specific annular zone where the segment meridian IV of the cornea is located. Preferably, the segment meridian of the orthokeratological lens is the one meridian whose mean arrow height is the middle value among all the meridians within the annular sector area in which the segment meridian is located.

[0037] In one embodiment of the present invention, the sectional meridian of the orthokeratological lens is: A division meridian I35, among all meridians between the flattest meridian 6 of the orthocorneal lens and the steepest meridian 7 of the orthocorneal lens, one meridian whose mean arrow height is the middle value is selected as the division meridian I35 of the orthocorneal lens; a division meridian II36, in which one meridian having a median mean arrow height among all meridians between the steepest meridian 7 of the orthocorneal lens and the next flattest meridian 8 of the orthocorneal lens is selected as the division meridian II36 of the orthocorneal lens; a division meridian III37, in which one meridian whose mean arrow height is intermediate among all meridians between the next flattest meridian 8 of the orthocorneal lens and the next steepest meridian 9 of the orthocorneal lens is selected as the division meridian III37 of the orthocorneal lens; and a division meridian IV38, which selects one meridian whose mean arrow height is intermediate among all meridians between the next steepest meridian 9 of the orthocorneal lens and the flattest meridian 6 of the orthocorneal lens as the division meridian IV38 of the orthocorneal lens.

[0038] Preferably, two partial annular sector areas of the annular sector area of ​​the orthocorneal lens are connected in a gradual transition, and the inner surfaces of the two partial annular sector areas form a smooth curved surface, in other words, the curvature value of the inner surfaces of the partial annular sector areas increases or decreases uniformly along the circumferential direction of the alignment curve area 3.

[0039] Preferably, the edge of the curvature of the annular sector of the orthokeratric lens, at which the two meridians dividing said annular sector lie, transitions gradually towards the edge at which the dividing meridians within said annular sector lie.

[0040] In one embodiment of the present invention, The curvature value of the inner surface of the first annular sector area 31 first increases uniformly from the edge where the flattest meridian 6 of the orthodontic lens is located to the edge where the segment meridian I35 is located, and then increases uniformly from the edge where the segment meridian I35 is located to the edge where the steepest meridian 7 of the orthodontic lens is located. The curvature value of the inner surface of the second annular sector area 32 first tapers uniformly from the edge where the steepest meridian 7 of the orthodontic lens is located to the edge where the segment meridian II 36 is located, and then tapers uniformly from the edge where the segment meridian II 36 is located to the edge where the next flattest meridian 8 of the orthodontic lens is located. The curvature value of the inner surface of the third annular sector area 33 first increases uniformly from the edge of the orthodontic lens where the next flattest meridian 8 is located to the edge where the segment meridian III 37 is located, and then increases uniformly from the edge where the segment meridian III 37 is located to the edge where the next steepest meridian 9 is located of the orthodontic lens. The curvature value of the inner surface of the fourth annular sector area 34 tapers uniformly first from the edge where the next steepest meridian 9 of the orthodontic lens is located to the edge where the segment meridian IV 38 is located, and then from the edge where the segment meridian IV 38 is located to the edge where the flattest meridian 6 of the orthodontic lens is located.

[0041] More specifically, the closer the inner surface of the first annular sector area 31 is to the flattest meridian 6 of the orthodontic lens, the smaller the curvature value, i.e., the flatter it is, and the closer the inner surface of the first annular sector area 31 is to the steepest meridian 7 of the orthodontic lens, the larger the curvature value, i.e., the steeper it is. The curvature value of the inner surface of the second annular sector area 32 first uniformly tapers from the edge where the steepest meridian 7 of the orthodontic lens is located to the edge where the segment meridian II 36 is located, and then uniformly tapers from the edge where the segment meridian II 36 is located to the edge where the next flattest meridian 8 of the orthodontic lens is located; the closer the inner surface of the second annular sector area 32 is to the steepest meridian 7 of the orthodontic lens, the larger the curvature value, i.e., the steeper it is; and the closer the inner surface of the second annular sector area 32 is to the next flattest meridian 8 of the orthodontic lens, the smaller the curvature, i.e., the flatter it is. The curvature value of the inner surface of the third annular sector area 33 first increases uniformly from the edge where the next flattest meridian 8 of the orthodontic lens is located to the edge where the segment meridian III 37 is located, and then increases uniformly from the edge where the segment meridian III 37 is located to the edge where the next steepest meridian 9 of the orthodontic lens is located; the closer the inner surface of the third annular sector area 33 is to the next flattest meridian 8 of the orthodontic lens, the smaller the curvature value, i.e., the flatter it is; and the closer the inner surface of the third annular sector area 33 is to the next steepest meridian 9 of the orthodontic lens, the larger the curvature value, i.e., the steeper it is. The curvature value of the inner surface of the fourth annular sector area 34 first uniformly tapers from the edge where the next steepest meridian 9 of the orthodontic lens is located to the edge where the segment meridian IV 38 is located, and then uniformly tapers from the edge where the segment meridian IV 38 is located to the edge where the flattest meridian 6 of the orthodontic lens is located; the closer the inner surface of the fourth annular sector area 34 is to the next steepest meridian 9 of the orthodontic lens, the larger the curvature value, i.e., the steeper it becomes; and the closer the inner surface of the fourth annular sector area 34 is to the flattest meridian 6 of the orthodontic lens, the smaller the curvature value, i.e., the flatter it becomes.

[0042] Preferably, the curvature distribution of the inner surface in the range of the alignment curve area 3 where the segment meridian I35 of the orthocorneal lens, the segment meridian II36 of the orthocorneal lens, the segment meridian III37 of the orthocorneal lens, and the segment meridian IV38 of the orthocorneal lens are located is consistent with the curvature distribution of the anterior surface in the range of the specific annular zone where the segment meridians of the cornea are located.

[0043] In this four-axis asymmetric corneal correction lens, By locating the sectional meridian relative to the annular sector with a large mean arrow height span, the annular sector with a large mean arrow height span can be subdivided into two partial annular sectors. The sectional meridian is determined by taking the median of the mean arrow heights of all meridians within the annular sector where the sectional meridian is located, allowing for a more accurate fit to the surface shape of the patient's cornea. This allows each annular sector of the lens alignment curve area 3 to better fit the patient's cornea, further improving compatibility with the cornea, effectively preventing lens displacement, and optimizing the corrective effect on the cornea. The above-mentioned annular sector with a large mean arrow height span refers to a sector where the mean arrow height difference between two adjacent meridians is greater than 45 μm.

[0044] The four-axis asymmetric orthocorneal lens is used in the following manner. When worn, the center of the cornea is aligned with the center of the base curve area 5, and the orthodontic lens is placed directly on the cornea, bringing the anterior surface of the cornea into contact with the inner surface of the orthodontic lens. Because lacrimal fluid exists between the cornea and the orthodontic lens and the curvature of each meridian in the orthodontic lens alignment curve area 3 is different, the orthodontic lens slides over the cornea and reaches a stable state, where the anterior surface of the cornea fits snugly against the inner surface of the orthodontic lens, and the corneal meridians are aligned with those of the orthodontic lens, allowing the orthodontic lens to apply pressure to the cornea and achieve corneal correction.

[0045] The present invention further provides a preparation method, and the above-mentioned four-axis asymmetric orthocorneal lens is prepared by the preparation method, and the preparation method specifically includes: Step S10 of providing a lens body to be adjusted, the lens body having a base curve area 1, and a reverse curve area 2, an alignment curve area 3, and a peripheral curve area 4 formed successively from the periphery of the base curve area 1 outward; a step S20 of dividing the alignment curve area 3 into four circular sector areas via the flattest meridian 6, the next flattest meridian 8, the steepest meridian 7, and the next steepest meridian 9, all of which pass through the center of the base curve area 1; and a step of determining the flattest meridian 6, the next flattest meridian 8, the steepest meridian 7, and the next steepest meridian 9, which includes: a step S21 of obtaining several meridians of the cornea; Step S22: matching the center of the lens base curve area 1 of the lens body to be adjusted with the center of the cornea, and selecting an area corresponding to a specific annular zone on the cornea as an alignment curve area 3 of the lens body to be adjusted; Step S23: calculating the average arrow height from the anterior surface of the cornea to the horizontal plane of the corneal apex within a specific annular zone area where each meridian on the cornea is located; Step S24 of acquiring the flattest corneal meridian and the steepest corneal meridian, in which, among all the corneal meridians, the flattest corneal meridian is the one meridian with the smallest mean arrow height value, and the steepest corneal meridian is the one meridian with the largest mean arrow height value; Step S25 of acquiring the next flattest meridian and the next steepest meridian of the cornea, in which the next flattest meridian of the cornea is the one meridian with the smallest mean arrow height among the meridians that form an angle of 90° or more with the flattest meridian of the cornea, and the next steepest meridian of the cornea is the one meridian with the largest mean arrow height among the meridians that form an angle of 90° or more with the steepest meridian of the cornea; and step S20. Step S30 of obtaining an orthokeratological lens by adjusting the curvature distribution of the inner surface in a range of an alignment curve area 3 where the flattest meridian 6, the next flattest meridian 8, the steepest meridian 7, and the next steepest meridian 9 of the adjusted lens body are located, based on the curvature distribution of the anterior surface of the cornea in a range of a specific annular zone where the flattest meridian of the cornea, the next flattest meridian of the cornea, the steepest meridian of the cornea, and the next steepest meridian of the cornea are located, and and step S30, wherein the curvature distribution of the inner surface in the alignment curve area where the next flattest meridian of the orthodontic lens is located matches the curvature distribution of the outer surface in the specific annular zone area where the next flattest meridian of the cornea is located, the curvature distribution of the inner surface in the alignment curve area where the steepest meridian of the orthodontic lens is located matches the curvature distribution of the outer surface in the specific annular zone area where the steepest meridian of the cornea is located, and the curvature distribution of the inner surface in the alignment curve area where the next steepest meridian of the orthodontic lens is located matches the curvature distribution of the outer surface in the specific annular zone area where the next steepest meridian of the cornea is located, and a gradual transition process is performed between adjacent annular sector areas.

[0046] The preparation method comprises: The method further includes step S40 of obtaining a corneal segment meridian, where the corneal segment meridian is a meridian located between adjacent meridians when the difference in mean arrow height between the adjacent meridians on the cornea is greater than 45 μm, and the corneal segment meridian divides the annular sector area formed by the adjacent meridians into two partial annular sector areas; and step S41 of obtaining an orthokeratological lens by adjusting the segment meridian of the lens body to be adjusted based on the curvature distribution of the anterior surface of the cornea in the range of the specific annular zone area where the corneal segment meridian is located, whereby the curvature distribution of the inner surface of the orthokeratological lens in the range of alignment curve area 3 where the segment meridian of the cornea is located matches the curvature distribution of the outer surface of the cornea in the range of the specific annular zone area where the corneal segment meridian is located, and a gradual transition process is performed between adjacent partial annular sector areas.

[0047] Preferably, the dividing meridian of the orthocorneal lens is one meridian between two adjacent meridians whose mean arrow height is the middle value.

[0048] To summarize the above, the four-axis asymmetric orthodontic lens provided by the present invention determines the four meridians of the lens body based on the mean arrow height value within a specific annular zone on the cornea, and the four meridians divide the alignment curve area 3 of the lens body into four annular sectors, and assign different curvatures to each meridian. Subsequently, separate curvature designs are performed for the curved surfaces of the four annular sectors. Furthermore, by assigning a dividing meridian to the annular sector with a large mean arrow height value span, the annular sector with a large mean arrow height value span can be subdivided into two partial annular sectors, which can more accurately match the surface shape of the patient's cornea, allowing the orthodontic lens to fit the wearer's cornea better and achieve a better fit.

[0049] The above-described examples are merely intended to explain the technical ideas and features of the present invention, and their purpose is to enable those skilled in the art to understand the contents of the present invention and to practice the invention based on them. The scope of the claims of the present invention is not limited solely by these examples. In other words, equivalent modifications or alterations made based on the spirit of the present invention still fall within the scope of the claims of the present invention. [Explanation of symbols]

[0050] 1 Base curve area 2. Reverse Curve Area 3 Alignment Curve Area 31 First circular sector area 32 Second circular sector area 33 Third circular sector area 34 Fourth circular sector area 35 Section molecular meridian I 36 Section Molecular Meridian II 37 Section molecular meridian III 38 Section molecular meridian IV 4 Peripheral curve area 5 Center of the base curve area 6. Flattest meridian 7. Steepest Meridian 8. Next, the flat meridian 9 Next Steepest Meridian

Claims

1. A four-axis asymmetric orthocorneal lens, The eyeglasses are provided with a base curve area (1), a reverse curve area (2), an alignment curve area (3), and a peripheral curve area (4) which are formed continuously in this order from the periphery of the base curve area (1) toward the outside, The orthocorneal lens has several meridians arranged thereon, and the portions of each meridian on the inner surface of the alignment curve area (3) and the horizontal plane of the apex of the inner surface of the orthocorneal lens all have an average arrow height value. Of all the meridians on the orthocorneal lens, the one meridian with the smallest average arrow height value is the flattest meridian (6), and the one meridian with the largest average arrow height value is the steepest meridian (7), and the included angles with all of the flattest meridians (6) are Among the meridians whose included angles with the steepest meridians (7) are 90° or more, the one meridian with the smallest mean arrow height value is the next flattest meridian (8), and among the meridians whose included angles with all of the steepest meridians (7) are 90° or more, the one meridian with the largest mean arrow height value is the next steepest meridian (9), and the alignment curve area (3) is divided into four circular fan-shaped areas by the flattest meridian (6), the next flattest meridian (8), the steepest meridian (7), and the next steepest meridian (9); The center of the base curve area (1) corresponds to the center of the cornea, and the area on the cornea corresponding to the alignment curve area (3) is defined as a specific annular zone area, and the curvature distribution of the inner surface in the range of the alignment curve area where the flattest meridian of the orthocorneal lens is located is consistent with the curvature distribution of the outer surface in the range of the specific annular zone area where the flattest meridian of the cornea is located; the curvature distribution of the inner surface in the alignment curve area where the next flattest meridian of the orthocorneal lens is located is consistent with the curvature distribution of the outer surface in the specific annular zone area where the next flattest meridian of the cornea is located; The curvature distribution of the inner surface in the range of the alignment curve area where the steepest meridian of the orthocorneal lens is located is consistent with the curvature distribution of the outer surface in the range of the specific annular zone area where the steepest meridian of the cornea is located; A four-axis asymmetric orthodontic lens, wherein the curvature distribution of the inner surface in the range of the alignment curve area where the next steepest meridian of the orthodontic lens is located is consistent with the curvature distribution of the outer surface in the range of the specific annular zone area where the next steepest meridian of the cornea is located.

2. 2. The four-axis asymmetric orthocorneal lens of claim 1, wherein the connection between adjacent annular sector areas is a gradual transition, and the curvature of each of the annular sector areas is a gradual transition between the edges where the two meridians that divide the annular sector areas are located.

3. In the orthocorneal lens, when the difference in the mean arrow height between the adjacent meridians is greater than 45 μm, the sectional meridian of the orthocorneal lens is disposed between the adjacent meridians; a dividing meridian of the orthokeratological lens divides an annular sector area formed by adjacent meridians into two partial annular sector areas; 2. The four-axis asymmetric orthodontic lens according to claim 1, wherein the curvature distribution of the inner surface in the range of the alignment curve area (3) where the lateral meridian of the orthodontic lens is located is consistent with the curvature distribution of the anterior surface of the cornea in the range of a specific annular zone where the lateral meridian of the cornea is located.

4. The four-axis asymmetric orthocorneal lens according to claim 3, wherein the meridian of the orthocorneal lens is the one meridian whose mean arrow height value is the median value among all meridians within the annular sector area in which the meridian is located.

5. 4. The four-axis asymmetric orthocorneal lens according to claim 3, wherein two partial annular sector areas within the annular sector area are connected in a gradual transition, and the inner surfaces of the two partial annular sector areas form a smoothly curved surface.

6. 4. The four-axis asymmetric orthodontic lens of claim 3, wherein the curvature of the annular sector area transitions gradually from the edge where the two meridians dividing the annular sector area are located to the edge where the dividing meridian within the annular sector area is located.

7. 1. A method for preparing a four-axis asymmetric orthocorneal lens, comprising: Step S10 of providing a lens body to be adjusted, the lens body having a base curve area (1), and a reverse curve area (2), an alignment curve area (3), and a peripheral curve area (4) formed successively from the periphery of the base curve area (1) toward the outside; Step S20 divides the alignment curve area (3) into four annular sector areas via the flattest meridian (6), the next flattest meridian (8), the steepest meridian (7), and the next steepest meridian (9), all of which pass through the center of the base curve area (1). The steps of determining the flattest meridian (6), the next flattest meridian (8), the steepest meridian (7), and the next steepest meridian (9) include step S21 of obtaining several meridians of the cornea, step S22 of matching the center of the base curve area (1) of the lens body to be adjusted with the center of the cornea and selecting an area corresponding to a specific annular zone on the cornea as the alignment curve area (3) of the lens body to be adjusted, and step S23 of measuring the horizontal axis of the vertex of the cornea from the anterior surface of the cornea within the range of the specific annular zone where each meridian on the cornea is located. Step S23 of calculating the average arrow height value to the surface; Step S24 of obtaining the flattest meridian of the cornea and the steepest meridian of the cornea, where, among all the meridians of the cornea, the flattest meridian of the cornea is the one meridian with the smallest average arrow height value, and the steepest meridian of the cornea is the one meridian with the largest average arrow height value; Step S24 of obtaining the next flattest meridian of the cornea and the next steepest meridian of the cornea Step S25 of acquiring meridians, in which the next flattest meridian of the cornea is the one meridian with the smallest mean arrow height among the meridians that form an angle of 90° or more with the flattest meridian of the cornea, and the next steepest meridian of the cornea is the one meridian with the largest mean arrow height among the meridians that form an angle of 90° or more with the steepest meridian of the cornea; and Step S20. based on the curvature distribution of the anterior surface of the cornea in the range of the specific annular zone in which the flattest meridian of the cornea, the next flattest meridian of the cornea, the steepest meridian of the cornea, and the next steepest meridian of the cornea are located, Step S30 of obtaining the orthocorneal lens by adjusting the curvature distribution of the inner surface in the range of the alignment curve area (3) where the flattest meridian (6) of the adjusted lens body, the next flattest meridian (8) of the adjusted lens body, the steepest meridian (7) of the adjusted lens body, and the next steepest meridian (9) of the adjusted lens body are located, wherein the orthocorneal lens makes the curvature distribution of the inner surface in the range of the alignment curve area where the flattest meridian of the orthocorneal lens is located match the curvature distribution of the outer surface in the range of the specific annular zone where the flattest meridian of the cornea is located, and the curvature distribution of the alignment curve area where the next flattest meridian of the orthocorneal lens is located match the curvature distribution of the outer surface in the range of the specific annular zone where the flattest meridian of the cornea is located. and step S30, wherein the curvature distribution of the inner surface in the range matches the curvature distribution of the outer surface in the specific annular zone where the next flattest meridian of the cornea is located, the curvature distribution of the inner surface in the range of the alignment curve area where the steepest meridian of the orthocorneal lens is located matches the curvature distribution of the outer surface in the specific annular zone where the steepest meridian of the cornea is located, and the curvature distribution of the inner surface in the range of the alignment curve area where the next steepest meridian of the orthocorneal lens is located matches the curvature distribution of the outer surface in the specific annular zone where the next steepest meridian of the cornea is located, and a gradual transition process is performed between adjacent annular sector areas.

8. Step S40: obtaining a corneal meridian, the corneal meridian being a meridian located between adjacent meridians when the difference in mean arrow height between the adjacent meridians on the cornea is greater than 45 μm, and the corneal meridian divides the annular sector area formed by the adjacent meridians into two partial annular sector areas; and Step S40: adjusting the annular meridian of the lens body to be adjusted based on the curvature distribution of the anterior surface of the cornea in the range of the specific annular zone where the corneal meridian is located. and step S41 of obtaining the orthocorneal lens in response to the alignment curve area (3) where the segment meridian of the orthocorneal lens is located, wherein the curvature distribution of the inner surface of the orthocorneal lens in the range of the alignment curve area (3) where the segment meridian of the orthocorneal lens is located matches the curvature distribution of the outer surface of the cornea in the range of a specific annular zone where the segment meridian of the cornea is located, and a gradual transition process is performed between adjacent partial annular sector areas.

9. 9. The method for preparing a four-axis asymmetric orthocorneal lens according to claim 8, wherein the dividing meridian of the orthocorneal lens is one meridian between two adjacent meridians whose mean arrow height value is the intermediate value.

10. 8. The method for preparing a four-axis asymmetric orthocorneal lens according to claim 7, wherein the base curve area (1), the reverse curve area (2), the alignment curve area (3), and the peripheral curve area (4) are integrally molded from the inside to the outside.

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