Orthokeratology lens based on big data elliptic model

Abstract

The invention relates to the technical field of orthokeratology lenses based on a big data elliptic model, in particular to an orthokeratology lens based on a big data elliptic model. According to the orthokeratology lens based on the big data elliptic model, through the design of a positioning arc area which is more fit with the cornea of a patient, the fit degree of the lens and the cornea is remarkably improved, and therefore the wearing comfort and the lens stability are improved. Compared with a traditional design method based on the average curvature of the joint points, the virtual ellipse model provides curvature calculation of continuous change of a positioning arc area, so that the lens design better conforms to the actual cornea shape and is better matched with the cornea of a patient. Besides, due to the design, the preset eccentricity rate value can be obtained according to the radius of the cornea of the patient, an optometrist can accurately fit the orthokeratology lens without additional knowledge or operation, and the problem that the orthokeratology lens is inaccurate in fitting or low in efficiency due to insufficient experience of a doctor (or the optometrist) is solved. Therefore, the lens matching efficiency, accuracy and wearing comfort of the orthokeratology lens are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of orthokeratology lenses, and in particular to an orthokeratology lens based on a big data elliptical model. Background Art

[0002] Existing orthokeratology lenses are usually designed based on zones, including base arc zone, reverse arc zone, fitting arc zone (positioning arc zone) and peripheral arc zone. In the traditional method, the radius of the positioning arc zone is calculated based on the average corneal curvature of the corneal topography under the junction point. This method may lead to insufficient fitting accuracy of the positioning arc zone, affect the wearing comfort and stability of the lens, and may even cause incorrect corneal reshaping.

[0003] In addition, in the existing technology, optometrists are required to extract multiple parameters from corneal topography data, which increases the time and workload of fitting. The accuracy is also affected by the optometrist's operational stability and technical level when taking the topography, which makes the fitting efficiency, accuracy and wearing comfort of orthokeratology lenses low. Summary of the invention

[0004] 1. Technical issues to be resolved

[0005] In view of the above-mentioned shortcomings and deficiencies of the prior art, the present invention provides a corneal reshaping lens based on a big data elliptical model, which solves the technical problems of low fitting efficiency, accuracy and wearing comfort of the existing corneal reshaping lenses.

[0006] (II) Technical solution

[0007] In order to achieve the above object, the main technical solutions adopted by the present invention include:

[0008] An embodiment of the present invention provides a corneal reshaping lens based on a big data elliptical model. The corneal reshaping lens comprises a base arc area, a reversal arc area, a first positioning arc area, a second positioning arc area and a peripheral arc area which are arranged continuously from the inside to the outside. The base arc area, the reversal arc area, the first positioning arc area and the second positioning arc area are obtained by the following steps:

[0009] S1. Based on the pre-acquired pupil radius pr, obtain the base arc segment length BCJ of the base arc area;

[0010] S2. Obtain the base curve radius BCR of the base curve area based on the pre-acquired mean curvature value FK of the central 4 mm diameter of the cornea, the patient's actual subjective optometry refraction RX and the overcorrection value PW;

[0011] S3, based on the actual subjective optometry refraction degree RX of the patient, obtaining the reversal arc segment length RCJ of the reversal arc;

[0012] S4, based on the base arc segment length BCJ and the base arc radius BCR, obtaining the reversal arc radius RCR of the reversal arc area;

[0013] S5, based on the base arc segment length BCJ, the reverse arc segment length RCJ and the previously acquired visible iris diameter HWTW, obtain the positioning arc segment length ACJ1 of the first positioning arc zone and the positioning arc segment length ACJ2 of the second positioning arc zone;

[0014] S6. Based on the average curvature value FK of the central 4mm diameter of the cornea, the corneal radius R0 is obtained. Based on the corneal radius R0, the pre-acquired eccentricity e corresponding to R0, the base arc segment length BCJ and the reversal arc segment length RCJ, according to the elliptical model formula, the positioning arc radius ACR1 of the first positioning arc zone and the positioning arc radius ACR2 of the second positioning arc zone are obtained.

[0015] Preferably, the length of the first positioning arc segment of the first positioning arc zone is ACJ1;

[0016] When 12mm≤HWTW<12.8mm, ACJ1=0.8mm;

[0017] When 11.2mm<HWTW<12mm, ACJ1=0.7mm;

[0018] The length of the second positioning arc segment of the second positioning arc zone is ACJ2;

[0019] ACJ2=(HWTW-1.2) / 2-BCJ-RCJ-ACJ1-0.4.

[0020] Preferably, based on the average curvature value FK of the central 4 mm diameter of the cornea, the corneal radius R0 is obtained according to formula (1);

[0021] Formula (1) is:

[0022]

[0023] Based on the corneal radius R0, the pre-acquired eccentricity e corresponding to the corneal radius R0, the base arc segment length BCJ and the reverse arc segment length RCJ, according to the ellipse model formula (2), the first positioning arc radius of the first positioning arc area is obtained as ACR1;

[0024] Formula (2) is:

[0025]

[0026] Among them, ACS1 is the starting point of the arc length of the first positioning arc zone, and the value of ACS1 is BCJ+RCJ;

[0027] Based on the corneal radius R0, the pre-acquired eccentricity e corresponding to the corneal radius R0, the base arc segment length BCJ and the reverse arc segment length RCJ, according to the ellipse model formula (3), the second positioning arc radius of the second positioning arc area is obtained as ACR2;

[0028] Formula (3) is:

[0029]

[0030] Among them, ACS2 is the starting end of the arc length of the second positioning arc area, and the value of ACS2 is BCJ+RCJ+ACJ1.

[0031] Preferably, the range of the eccentricity e is: 0.18<e<0.93.

[0032] Preferably, the peripheral arc area is obtained by the following steps:

[0033] S7. The peripheral arc segment length PCJ of the peripheral arc zone is a constant. Based on the corneal curvature value corresponding to the peripheral arc segment length PCJ in the actual corneal topography, the peripheral arc radius PCR of the peripheral arc zone is obtained.

[0034] Preferably, S1 specifically includes: based on the pre-acquired pupil radius pr, obtaining the base arc segment length BCJ of the base arc area according to formula (4);

[0035] Formula (4) is:

[0036] BCJ = pr + 1.4 mm;

[0037] S2 specifically includes: based on the pre-acquired corneal central 4 mm diameter average curvature value FK, the patient's actual subjective optometry refraction RX and the overcorrection value PW, the base curve radius BCR of the base curve area is obtained using formula (4);

[0038] Formula (5) is:

[0039] BCR = 337.5 / (FK-RX-PW).

[0040] Preferably, when RX is between -1.00D and -3.00D, PW = 0.75D;

[0041] When RX is between -3.00D and -6.00D, PW=1.00D.

[0042] Preferably, when RX is between -0.25D and -1.00D, RCJ = 0.45mm;

[0043] When RX is between -1.00D and -3.00D, RCJ = 0.5mm;

[0044] When RX is between -3.00D and -6.00D, RCJ = 0.6mm.

[0045] Preferably, S4 specifically includes:

[0046] Based on the base arc segment length BCJ and the base arc radius BCR, the reversal arc radius RCR of the reversal arc zone is obtained using formula (6);

[0047] Formula (6) is:

[0048]

[0049] Wherein, b is the first correction coefficient, 0.306<b<4.862.

[0050] Preferably, S7 specifically includes:

[0051] The peripheral arc segment length PCJ of the peripheral arc zone is 0.4 mm. Based on the corneal curvature value corresponding to the peripheral arc segment length PCJ in the actual corneal topography, the peripheral arc radius PCR of the peripheral arc zone is obtained using formula (7);

[0052] Formula (7) is:

[0053] PCR = 337.5 / SPC + c;

[0054] Wherein, SPC is the average corneal curvature corresponding to the length PCJ of the peripheral arc segment of the actual corneal topography, c is the second correction coefficient, 1.625<c<4.663.

[0055] (III) Beneficial effects

[0056] The beneficial effects of the present invention are:

[0057] The orthokeratology lens based on the big data elliptical model of the present invention significantly improves the fit between the lens and the cornea by designing a positioning arc zone that fits the patient's cornea more closely, thereby improving the wearing comfort and stability of the lens. Compared with the traditional design method based on the average curvature of the junction point, the virtual elliptical model provides a continuously changing curvature calculation for the positioning arc zone, so that the lens design is more in line with the actual corneal shape and thus better matches the patient's cornea. In addition, because the design can obtain a preset eccentricity value based on the patient's corneal radius, optometrists can accurately fit the glasses without additional knowledge or operation, avoiding the problem of inaccurate or inefficient fitting of orthokeratology lenses due to lack of experience by doctors (or optometrists), thereby improving the fitting efficiency, accuracy and wearing comfort of orthokeratology lenses. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Figure 1 It is a cross-sectional schematic diagram of the orthokeratology lens of the present invention. DETAILED DESCRIPTION

[0059] In order to better explain the present invention and facilitate understanding, the present invention is described in detail below through specific implementation modes in conjunction with the accompanying drawings.

[0060] The embodiment of the present invention provides a corneal reshaping lens based on a big data elliptical model, such as Figure 1 As shown, the orthokeratology lens comprises a base arc zone, a reversal arc zone, a first positioning arc zone, a second positioning arc zone and a peripheral arc zone which are arranged continuously from the inside to the outside, and the base arc zone, the reversal arc zone, the first positioning arc zone, the second positioning arc zone and the peripheral arc zone are obtained by the following steps;

[0061] S1. Based on the pre-acquired pupil radius pr, obtain the base arc segment length BCJ of the base arc area;

[0062] S2. Obtain the base curve radius BCR of the base curve area based on the pre-acquired mean curvature value FK of the central 4 mm diameter of the cornea, the patient's actual subjective optometry refraction RX and the overcorrection value PW;

[0063] S3, based on the actual subjective optometry refraction degree RX of the patient, obtaining the reversal arc segment length RCJ of the reversal arc;

[0064] S4, based on the base arc segment length BCJ and the base arc radius BCR, obtaining the reversal arc radius RCR of the reversal arc area;

[0065] S5, based on the base arc segment length BCJ, the reverse arc segment length RCJ and the previously acquired visible iris diameter HWTW, obtain the positioning arc segment length ACJ1 of the first positioning arc zone and the positioning arc segment length ACJ2 of the second positioning arc zone;

[0066] S6. Based on the average curvature value FK of the central 4 mm diameter of the cornea, the corneal radius R0 is obtained. Based on the corneal radius R0, the pre-acquired eccentricity e corresponding to R0, the base arc segment length BCJ and the reverse arc segment length RCJ, according to the ellipse model formula, the positioning arc radius ACR1 of the first positioning arc zone and the positioning arc radius ACR2 of the second positioning arc zone are obtained.

[0067] S7. The peripheral arc segment length PCJ of the peripheral arc zone is a constant. Based on the corneal curvature value corresponding to the peripheral arc segment length PCJ in the actual corneal topography, the peripheral arc radius PCR of the peripheral arc zone is obtained.

[0068] It should be noted that the patient's actual corneal morphology and arc segment data within the visible iris diameter range from the central zone to the peripheral zone can be measured through the corneal topography, that is, the actual average corneal curvature radius corresponding to each measured width of the entire cornea can be measured based on the patient's corneal topography.

[0069] By designing a positioning arc zone that fits the patient's cornea more closely, the fit between the lens and the cornea is significantly improved, thereby improving the wearing comfort and stability of the lens. Compared with the traditional design method based on the average curvature of the junction point, the virtual elliptical model provides a continuously changing curvature calculation for the positioning arc zone, making the lens design more consistent with the actual corneal shape and thus more compatible with the patient's cornea. In addition, since the design can obtain a preset eccentricity value based on the patient's corneal radius, optometrists can accurately fit glasses without additional knowledge or operation, avoiding the problem of inaccurate or inefficient fitting of orthokeratology lenses due to lack of experience by doctors (or optometrists), thereby improving the fitting efficiency, accuracy and wearing comfort of orthokeratology lenses.

[0070] Preferably, the length of the first positioning arc segment of the first positioning arc zone is ACJ1, when 12mm≤HWTW<12.8mm, ACJ1=0.8mm; when 11.2mm<HWTW<12mm, ACJ1=0.7mm, and the length of the second positioning arc segment of the second positioning arc zone is ACJ2, ACJ2=(HWTW-1.2) / 2-BCJ-RCJ-ACJ1-0.4.

[0071] The corneal radius R0 is obtained based on the average curvature value FK of the corneal center 4 mm diameter according to formula (1).

[0072] Formula (1) is:

[0073]

[0074] According to the ellipse model formula (2), the first positioning arc radius of the first positioning arc area is obtained as ACR1, and according to the ellipse model formula (3), the second positioning arc radius of the second positioning arc area is obtained as ACR2.

[0075] Formula (2) is:

[0076]

[0077] Among them, ACS1 is the starting end of the arc length of the first positioning arc zone, and the value of ACS1 is BCJ+RCJ.

[0078] Formula (3) is:

[0079]

[0080] Among them, ACS2 is the starting end of the arc length of the second positioning arc area, and the value of ACS2 is BCJ+RCJ+ACJ1.

[0081] It should be noted that based on a large amount of corneal topography data (more than 10,000 samples), a correlation model between corneal radius R0 and eccentricity e was established through big data analysis and machine learning technology. Once the patient's corneal radius R0 is determined, the correlation model can be used to quickly calculate or predict the eccentricity e suitable for the patient, where the range of eccentricity e is: 0.18<e<0.93.

[0082] Preferably, based on the pre-acquired pupil radius pr, the base arc segment length BCJ of the base arc zone is obtained according to formula (4). Based on the pre-acquired corneal central 4 mm diameter average curvature value FK, the patient's actual subjective optometry refraction power RX and the overcorrection value PW, the base arc radius BCR of the base arc zone is obtained using formula (5).

[0083] Formula (4) is: BCJ = pr + 1.4 mm.

[0084] Formula (5) is: BCR = 337.5 / (FK-RX-PW).

[0085] Among them, when RX is between -1.00D and -3.00D, PW = 0.75D; when RX is between -3.00D and -6.00D, PW = 1.00D. When RX is between -0.25D and -1.00D, RCJ = 0.45mm; when RX is between -1.00D and -3.00D, RCJ = 0.5mm; when RX is between -3.00D and -6.00D, RCJ = 0.6mm.

[0086] Preferably, based on the base arc segment length BCJ and the base arc radius BCR, formula (6) is used to obtain the reversal arc radius RCR of the reversal arc zone.

[0087] Formula (6) is: Wherein, b is the first correction coefficient, 0.306<b<4.862, and the value of b is determined according to the condition of the patient's cornea.

[0088] Among them, the peripheral arc segment length PCJ of the peripheral arc zone is 0.4 mm. Based on the corneal curvature value corresponding to the peripheral arc segment length PCJ in the actual corneal topography, the peripheral arc radius PCR of the peripheral arc zone is obtained using formula (7);

[0089] Formula (7) is: PCR = 337.5 / SPC + c, where SPC is the average corneal curvature corresponding to the length PCJ of the peripheral arc segment of the actual corneal topography, c is the second correction coefficient, 1.625 < c < 4.663, and the value of c is determined based on the patient's comfort requirements for the lens and the morphology of the cornea at this position.

[0090] In summary, in this embodiment, the curvature of the first positioning arc area and the second positioning arc area are obtained according to the ellipse formula, which is more in line with the actual cornea. At the same time, in the ellipse formula, since the values ​​of ACS1 and ACS2 are fixed values ​​and not variables, the requirements for existing production equipment are not high. Therefore, ACR1 and ACR2 obtained by the ellipse formula in implementation are as close as possible to the actual positioning arc corneal curvature, more in line with actual production, and more widely used. At the same time, the acquisition of ACR1 and ACR2 minimizes the use of actual corneal topography, so the acquisition of ACR1 and ACR2 is more accurate.

[0091] Embodiment 1

[0092] In this embodiment, taking the glasses fitting condition of the right eye of patient A as an example, the actual refraction power is: RX=-1.75D, the visible iris diameter is: HWTW=11.8mm, FK=43.00D, the overcorrection value is: PW=0.75D, the pupil radius pr=1.4mm, and the above parameters are all measured according to the actual corneal topography of the patient.

[0093] Among them, R0=337.5 / 43.00=7.85mm; e=0.65;

[0094] BCJ=pr+1.4mm=2.8mm.

[0095] Since RX is between -1.00D and -3.00D, RCJ = 0.5mm.

[0096] Since 11.2mm<HWTW<12mm, ACJ1=0.7mm;

[0097] ACS1=BCJ+RCJ=2.8+0.5=3.3mm;

[0098] ACS2=BCJ+RCJ+ACJ1=2.8+0.5+0.7=4.0mm;

[0099] Therefore, ACR1=8.48mm; ACR2=8.82mm.

[0100] Embodiment 2

[0101] RX = -2.75D;

[0102] PW = 0.75D;

[0103] RCJ = 0.5 mm;

[0104] HWTW=12.2mm;

[0105] ACJ1 = 0.8 mm;

[0106] FK = 42.50D;

[0107] R0 = 337.5 / 42.50 = 7.94 mm;

[0108] e = 0.70;

[0109] pr = 1.5 mm;

[0110] BCJ = pr + 1.4 = 2.9 mm;

[0111] ACS1=BCJ+RCJ=2.9+0.5=3.4mm;

[0112] ACS2=BCJ+RCJ+ACJ1=2.9+0.5+0.8=4.2mm;

[0113] Therefore, ACR1=8.72mm; ACR2=9.2mm.

[0114] In summary, the orthokeratology lens based on the big data elliptical model in this embodiment can obtain accurate fitting parameters, so that the orthokeratology lens is more matched with the patient's cornea, improving accuracy and wearing comfort.

[0115] In the description of the present invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0116] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0117] In the present invention, unless otherwise clearly specified and limited, when a first feature is “on” or “below” a second feature, it may be that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, when a first feature is “above”, “above” or “above” a second feature, it may be that the first feature is directly above or obliquely above the second feature, or it may simply mean that the first feature is higher in level than the second feature. When a first feature is “below”, “below” or “below” a second feature, it may be that the first feature is directly below or obliquely below the second feature, or it may simply mean that the first feature is lower in level than the second feature.

[0118] In the description of this specification, the description of the terms "one embodiment", "some embodiments", "embodiment", "example", "specific example" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are contradictory.

[0119] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may alter, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A corneal reshaping lens based on a big data elliptical model, the corneal reshaping lens comprises a base arc area, a reverse arc area, a first positioning arc area, a second positioning arc area and a peripheral arc area which are arranged continuously from the inside to the outside, characterized in that: The base arc area, the reverse arc area, the first positioning arc area and the second positioning arc area are obtained by the following steps; S1. Based on the pupil radius pr obtained in advance, obtaining the base arc segment length BCJ of the base arc area; S2, obtaining the base curve radius BCR of the base curve area based on the pre-acquired average curvature value FK of the central 4 mm diameter of the cornea, the patient's actual subjective optometry refraction RX and the overcorrection value PW; S3, based on the actual subjective optometry refraction degree RX of the patient, obtaining the reversal arc segment length RCJ of the reversal arc; S4, obtaining a reversal arc radius RCR of the reversal arc zone based on the base arc segment length BCJ and the base arc radius BCR; S5, based on the base arc segment length BCJ, the reverse arc segment length RCJ and the pre-acquired visible iris diameter HWTW, acquiring the positioning arc segment length ACJ1 of the first positioning arc zone and the positioning arc segment length ACJ2 of the second positioning arc zone; S6. Based on the average curvature value FK of the central 4 mm diameter of the cornea, the corneal radius R0 is obtained. Based on the corneal radius R0, the pre-acquired eccentricity e corresponding to R0, the base arc segment length BCJ and the reversal arc segment length RCJ, according to the elliptical model formula, the positioning arc radius ACR1 of the first positioning arc zone and the positioning arc radius ACR2 of the second positioning arc zone are obtained.

2. The orthokeratology lens based on the big data elliptical model according to claim 1, characterized in that: The length of the first positioning arc segment of the first positioning arc zone is ACJ1; When 12mm≤HWTW<12.8mm, ACJ1=0.8mm; When 11.2mm<HWTW<12mm, ACJ1=0.7mm; The length of the second positioning arc segment of the second positioning arc zone is ACJ2; ACJ2=(HWTW-1.2) / 2-BCJ-RCJ-ACJ1-0.

4.

3. The orthokeratology lens based on the big data elliptical model according to claim 1, characterized in that: The step S6 specifically includes: obtaining the corneal radius R0 based on the average curvature value FK of the corneal central 4 mm diameter according to formula (1); The formula (1) is: Based on the corneal radius R0, the pre-acquired eccentricity e corresponding to the corneal radius R0, the base arc segment length BCJ and the reverse arc segment length RCJ, according to the ellipse model formula (2), the first positioning arc radius of the first positioning arc zone is obtained as ACR1; The formula (2) is: Wherein, ACS1 is the starting point of the arc length of the first positioning arc zone, and the value of ACS1 is BCJ+RCJ; Based on the corneal radius R0, the pre-acquired eccentricity e corresponding to the corneal radius R0, the base arc segment length BCJ and the reverse arc segment length RCJ, according to the ellipse model formula (3), the second positioning arc radius of the second positioning arc area is obtained as ACR2; The formula (3) is: Among them, ACS2 is the starting end of the arc length of the second positioning arc area, and the value of ACS2 is BCJ+RCJ+ACJ1.

4. The orthokeratology lens based on the big data elliptical model according to claim 1, characterized in that: The range of the eccentricity e is: 0.18<e<0.

93.

5. The orthokeratology lens based on the big data elliptical model according to claim 1, characterized in that: The peripheral arc area is obtained by the following steps: S7. The peripheral arc segment length PCJ of the peripheral arc zone is a constant. Based on the corneal curvature value corresponding to the peripheral arc segment length PCJ in the actual corneal topography, the peripheral arc radius PCR of the peripheral arc zone is obtained.

6. The orthokeratology lens based on the big data elliptical model according to claim 1, characterized in that: The step S1 specifically includes: based on the pre-acquired pupil radius pr, obtaining the base arc segment length BCJ of the base arc area according to formula (3); The formula (4) is: BCJ = pr + 1.4 mm; The S2 specifically includes: based on the pre-acquired corneal central 4 mm diameter average curvature value FK, the patient's actual subjective optometry refraction power RX and the overcorrection value PW, using formula (4) to obtain the base curve radius BCR of the base curve area; The formula (5) is: BCR = 337.5 / (FK-RX-PW).

7. The method for manufacturing orthokeratology lenses based on a big data elliptical model according to claim 6, characterized in that: When RX is between -1.00D and -3.00D, PW = 0.75D; When RX is between -3.00D and -6.00D, PW=1.00D.

8. The orthokeratology lens based on the big data elliptical model according to claim 1, characterized in that: When RX is between -0.25D and -1.00D, RCJ = 0.45mm; When RX is between -1.00D and -3.00D, RCJ = 0.5mm; When RX is between -3.00D and -6.00D, RCJ = 0.6mm.

9. The orthokeratology lens based on the big data elliptical model according to claim 1, characterized in that: The S4 specifically includes: Based on the base arc segment length BCJ and the base arc radius BCR, the reversal arc radius RCR of the reversal arc zone is obtained using formula (5); The formula (6) is: Wherein, b is the first correction coefficient, 0.306<b<4.

862.

10. The orthokeratology lens based on big data elliptical model according to claim 5, characterized in that: The S7 specifically includes: The peripheral arc segment length PCJ of the peripheral arc zone is 0.4 mm. Based on the corneal curvature value corresponding to the peripheral arc segment length PCJ in the actual corneal topography, the peripheral arc radius PCR of the peripheral arc zone is obtained using formula (6); The formula (7) is: PCR = 337.5 / SPC + c; Wherein, SPC is the average value of corneal curvature corresponding to the peripheral arc segment length PCJ described in the actual corneal topography, c is the second correction coefficient, 1.625<c<4.663.

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