A Universal Anti-Fatigue Eyeglass Lens, Design Method and Preparation Mold

Abstract

The present invention relates to a general anti-fatigue spectacle lens, a design method and a preparation mold. The spectacle lens includes a first refractive region and a second refractive region respectively located above and below the lens, and a plus power transition zone connecting the two refractive regions; the first refractive region and the second refractive region are aspheric initial surface shapes, the plus power transition zone is a superimposed surface shape of a progressive multifocal surface, and the design surface is a superimposition of the initial surface shape and the superimposed surface shape. On the premise of retaining the design feature of combining the aspheric surface in the distance vision area and the plus power in the reading area of the traditional anti-fatigue design, beneficial astigmatism is combined in the plus power design in the reading area, overcoming the defect of irregular astigmatism around the traditional anti-fatigue lens. The spectacle lens provided by the present invention not only helps to relax accommodation and convergence when looking at near, but also avoids the defect of the contradiction between convergence and accommodation of exophoria population caused by long-term use of the reading area fixation of the traditional anti-fatigue lens, and is an anti-fatigue spectacle lens applicable to all age groups and all eye position populations.

Description

Technical Field

[0001] The present invention relates to a universal anti-fatigue spectacle lens, a design method and a preparation mold thereof, and particularly relates to a spectacle lens with a reduced decentered peripheral defocus design surface, a design method and a preparation mold thereof. Technical Background

[0002] Traditional anti-fatigue lenses or commercially available lenses commonly known as digital (XX) lenses are basically of the progressive multifocal addition design. Their characteristic is that no matter how much the addition increases, there is a stable photometric area with near addition in the reading area, which can form a long-term fixation; there is a blind area with non-linear photometric change and irregular astigmatism in the periphery. Even with the improvement of the peripheral astigmatism optimization technology brought by the increasing progress of modern progressive technology, it only reduces the blind area range and reduces the sense of blind area distortion, but cannot truly eliminate the blind area. Due to the above optical design characteristics, such anti-fatigue lenses have two problems in application. One is that the existence of peripheral non-linear and irregular astigmatism will increase the risk of wearing complaints for some special sensitive people; existing spectacle fitting practice data shows that if there is irregular astigmatism within a 30-degree field of view around the spectacle fitting center, as long as it exceeds 0.25D, it will interfere with some sensitive people. The other is that due to the existence of a stable fixation area in the reading addition part of the lens, for people with exophoria or insufficient convergence, due to the accommodation-convergence-pupil constriction triple linkage effect when the human eye looks at near, the phenomenon of insufficient convergence or exophoria will inevitably be aggravated while relaxing accommodation for a long time. Although the accommodation ability is improved, it is easy to cause convergence visual fatigue. And among the myopic population of East Asian ethnic groups, the proportion of exophoria is quite high. This drawback is particularly likely to cause adverse effects on people with exophoria under 35 years old wearing anti-fatigue lenses, because the need for help with accommodation is not obvious for this part of the population, and wearing traditional anti-fatigue lenses will instead increase the difficulty of convergence, and the disadvantages may outweigh the advantages. Summary of the Invention

[0003] Aiming at the deficiencies of the existing technology, the present invention provides a universal anti-fatigue spectacle lens, a design method and a preparation mold thereof, which retain the design characteristics of the aspheric surface in the distance area and the addition in the reading area of the traditional anti-fatigue design, and overcome the defect of irregular astigmatism in the periphery of the traditional anti-fatigue lens.

[0004] The technical solution for achieving the purpose of the present invention provides a universal anti-fatigue spectacle lens, which includes a first refractive area located above the lens, a second refractive area located below the lens, and a plus addition transition zone connecting the two refractive areas;

[0005] The first refractive region is aspherical and is used to correct refractive errors beyond 5 meters. The first refractive region includes a distant reference measurement point and a distant aspheric compensation value reference point. The distant reference measurement point is within 0 to 8 millimeters above the geometric center of the lens. The distant aspheric compensation value reference point is located 15 millimeters vertically upward from the distant reference measurement point as the center. The aspheric compensation value at the distant aspheric compensation value reference point is 5% to 10% of the optical power at the distant reference measurement point.

[0006] The second refractive region is aspherical and is used to relax accommodation and convergence during reading. It includes a near reference measurement point and an astigmatism measurement reference point. The near reference measurement point is within 8 to 14 millimeters below the geometric center of the lens. The astigmatism measurement reference point coincides with the near reference measurement point. The astigmatism value C0 at the astigmatism measurement reference point satisfies: C0 ≤ (C - C f ) / ADD × 70%, where C is the actual measured astigmatism value at the astigmatism measurement reference point, and C f is the prescribed astigmatism value.

[0007] The addition transition zone is the region where the optical power changes connecting the distant reference measurement point of the first refractive region and the near reference measurement point of the second refractive region. The change in optical power ADD of the addition transition zone satisfies: 0.25D ≤ ADD ≤ 0.60D.

[0008] The fitting center of the lens is set on the addition transition zone where the change in optical power is 10% - 20% ADD.

[0009] For the universal anti - fatigue spectacle lens described in the present invention, the contour lines of the change in peripheral optical power and astigmatism from the distant reference measurement point downward and to the left and right sides change linearly and unidirectionally.

[0010] The technical solution of the present invention also includes a design method for a universal anti - fatigue spectacle lens, with the following steps:

[0011] (1) Set a first refractive region on the lens, located above the lens, and a second refractive region below the lens. The first refractive region includes a distant reference measurement point and a distant aspheric compensation value reference point. The second refractive region includes a near reference measurement point and an astigmatism measurement reference point. The region where the optical power changes connecting the distant reference measurement point of the first refractive region and the near reference measurement point of the second refractive region is the addition transition zone. According to the refraction result, respectively determine the distances d1 and d2 of the distant reference measurement point of the first refractive region and the near reference measurement point of the second refractive region from the geometric center of the lens design surface, the optical power D1 of the distant reference measurement point of the first refractive region, and the change in optical power ADD of the addition transition zone, and obtain the optical power D2 of the near reference measurement point of the second refractive region as D1 + ADD.

[0012] (2) Using the aspheric surface as the initial surface shape design surface, with the sag of the aspheric surface as the initial surface shape expression of the design surface, and based on the parameters d1, d2, D1, and D2 obtained in step (1), calculate the quadratic surface parameters of the initial surface shape expression. The quadratic surface parameters include the basic curvature at the vertex and the conic constant;

[0013] (3) Move the vertex of the initial surface shape to the distance reference measurement point with an eccentricity of d1, and perform eccentricity processing on the initial surface shape;

[0014] (4) Use the differential geometry algorithm to obtain the optical power change D0(u) from the distance reference measurement point in the first refractive region of the initial surface shape to the near reference measurement point in the second refractive region;

[0015] (5) Use a third-order polynomial as the optical power change curve D(u) of the addition power transition zone of the design surface, and determine the optical power change curve D P (u) of the addition power transition zone of the stacked surface shape. D P (u) = D(u) - D0(u);

[0016] (6) Based on the optical power change curve D P (u) obtained in step (5), using the progressive multifocal surface as the stacked surface shape design surface, use the contour line mapping method to obtain the curvature radius distribution on the surface of the stacked surface shape, and calculate the sag of the stacked surface shape based on the curvature center coordinates corresponding to the curvature radius;

[0017] (7) Superimpose the stacked surface shape and the initial surface shape to obtain the sag of the design surface of a universal anti-fatigue spectacle lens;

[0018] (8) Use the design surface obtained in step (7) as one surface of the lens, and the other surface is one of a spherical surface, a toric surface, or a free surface to obtain a universal anti-fatigue spectacle lens.

[0019] The mold for preparing a universal anti-fatigue spectacle lens according to the present invention is formed by clamping an upper mold base and a lower mold base. The upper mold base has a concave surface for forming the front surface of the spectacle lens, and the lower mold base has a convex surface for forming the rear surface of the spectacle lens; the mold is a glass mold or a metal mold.

[0020] In the technical solution of the present invention, for the surface shape of the lens design surface, taking the geometric center of the lens as the origin, a Cartesian coordinate system is constructed. The positive direction of the y-axis is the rightward direction of the transverse meridian of the design surface, the positive direction of the x-axis is the downward direction of the longitudinal meridian of the design surface, and the positive direction of the z-axis is outward perpendicular to the paper surface.

[0021] According to the optometry results, determine the distances d1 and d2 of the far vision reference measurement point in the first refractive region and the near vision reference measurement point in the second refractive region from the geometric center of the design surface, the optical power D1 of the reference measurement point in the first refractive region, and the optical power change amount ADD of the addition power transition zone. Then, the optical power D2 of the reference measurement point in the second refractive region is D1 + ADD.

[0022] In the technical solution of the present invention, the aspheric surface is used as the initial surface shape of the design surface, and the sag of the aspheric surface is used as the initial surface shape expression of the design surface, as shown in Equation (1):

[0023] (1)

[0024] Where, c: the basic curvature at the vertex; k: the conic constant; r: the radial coordinate in the direction perpendicular to the optical axis, r 2 = x 2 + y 2 ;

[0025] When different values are selected for the conic constant k, the design surface shape presents different forms, and their relationships are as follows:

[0026] When k = 0, the surface type is a spherical surface;

[0027] When k < -1, the surface type is a hyperboloid;

[0028] When k = -1, the surface type is a paraboloid;

[0029] According to the parameters d1, d2, D1, and D2, calculate the quadratic surface parameters c and k of the initial surface shape expression.

[0030] Move the vertex of the initial surface shape to the far vision reference measurement point, and the sag expression of the initial surface shape after decentering the initial surface shape with an eccentricity of d1 is as shown in Equation (2):

[0031] (2)

[0032] Use the differential geometry algorithm to obtain the surface diopter of the initial surface shape, and its calculation is according to Formula (3):

[0033] (3)

[0034] n is the refractive index of the lens, and r1 and r2 are the maximum and minimum curvature radii of the corresponding points on the design surface, respectively, which satisfy the following quadratic equation (4):

[0035] (4)

[0036] Where,

[0037]

[0038] Then the optical power change from the distance reference measurement point of the first refractive area to the near reference measurement point of the second refractive area is D0(u)=D0(x,0);

[0039] The focal power change curve D(u) of the light addition transition zone with a third-order polynomial as the design surface is specifically expressed as follows (5):

[0040] (5)

[0041] Where m = 3, and the coefficients a0, a1, a2, and a3 are determined by the following equation group (6):

[0042] (6)

[0043] Where k0 is the variable that controls the speed of change of the optical power at the corresponding position, which can be determined according to the actual situation.

[0044] Determine the focal power change curve D of the light addition transition zone of the superimposed surface type P (u), D P (u)= D(u)- D0(u).

[0045] The superimposed face shape adopts a progressive multifocal face shape design.

[0046] Reference US5123725, using the contour mapping method to obtain the focal power distribution D of the superimposed surface p (x,y), the expression of the curve cluster is as follows:

[0047]

[0048] The curvature radius distribution of the corresponding points on the superimposed surface is obtained from the optical power distribution, and the calculation formula is as follows (7):

[0049] (7)

[0050] Referring to US5123725, the calculation formula for the center of curvature corresponding to each curvature radius is as follows (8):

[0051] (8)

[0052] A series of circles are constructed with the curvature radius and the corresponding curvature center coordinates. The envelope of these circles is the superimposed surface, and its vector height z p (x,y) is as shown in formula (9):

[0053] (9)

[0054] The surface elevation expression of the obtained design surface is: Z = z(x, y) + z p (x, y).

[0055] Compared with the prior art, the beneficial effects of the present invention are as follows: Due to the superposition of the aspherical surface and the progressive multifocal surface on the design surface of the spectacle lens provided by the present invention, the optical power has a slight change near the near vision area and the astigmatism in this area is reduced. Therefore, it not only helps to relax the accommodation and convergence when looking at near objects, but also to a certain extent avoids the defect of the contradiction between convergence and accommodation of the exophoria population caused by long-term fixation on the reading area of traditional anti-fatigue lenses. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Figure 1 is a schematic structural diagram of the universal anti-fatigue spectacle lens provided by the present invention;

[0057] In the figure, A: the reference measurement point of the first refractive region; B: the reference measurement point of the second refractive region; O: the geometric center of the lens; C: the fitting center;

[0058] Figure 2 、 3 are respectively the schematic diagrams of the optical power distribution and astigmatism distribution of the anti-fatigue lens of the comparative example;

[0059] Figure 4 、 5 are respectively the schematic diagrams of the optical power distribution and astigmatism distribution of the anti-fatigue lens provided in Embodiment 1 of the present invention;

[0060] Figure 6 、 7 are respectively the schematic diagrams of the optical power distribution and astigmatism distribution of the anti-fatigue lens provided in Embodiment 2 of the present invention;

[0061] Figure 8 、 9 are respectively the schematic diagrams of the optical power distribution and astigmatism distribution of the anti-fatigue lens provided in Embodiment 3 of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0062] The technical solution of the present invention will be further described below with reference to the drawings and embodiments.

[0063] Embodiment 1

[0064] In this embodiment, the radius R of the lens is 40 mm, the refractive index n is 1.56, and the optical power of the lens at the position for relaxing the accommodation and convergence functions during reading (the optical power of the near vision reference measurement point of the lens obtained from the optometry result) D 0 is 3.60 D (diopter), and the change amount of the optical power from the near vision reference measurement point to the far vision reference measurement point of the lens ADDIt is 0.60D. One refractive surface of the lens is an anti-fatigue design surface, which can be the front surface or the rear surface, and the other refractive surface of the lens is one of a spherical surface, a toric surface, and a freeform surface. At least one of the front surface and the rear surface of the spectacle lens is one of a spherical surface, a toric surface, and a freeform surface.

[0065] The specific design method of the anti-fatigue design surface of the lens is as follows:

[0066] Taking the geometric center of the design surface of the lens as the origin, a Cartesian coordinate system is constructed. The positive direction of the y-axis is the right direction of the transverse meridian of the design surface, the positive direction of the x-axis is the downward direction of the longitudinal meridian of the design surface, and the positive direction of the z-axis is perpendicular to the paper surface and outward.

[0067] Assuming that the near-vision measurement point of the lens is located at the geometric center of the lens and the length of the addition transition zone of the lens is 20 mm, the distance of the far-vision measurement point is at x = -20 mm, and the initial surface shape of the design surface is given by the following formula:

[0068]

[0069] Where:

[0070] c: The basic curvature at the vertex; k: The conic constant; r: The radial coordinate in the direction perpendicular to the optical axis;

[0071] r 2 = x 2 + y 2 .

[0072] When different values are selected for the conic constant k, the surface shape of the design surface presents different forms, and their relationships are as follows:

[0073] When k = 0, the surface type is a spherical surface;

[0074] When k < -1, the surface type is a hyperboloid;

[0075] When k = -1, the surface type is a paraboloid;

[0076] When -1 < k < 0, the surface type is an ellipsoid;

[0077] In this embodiment, the optical power distribution is selected as an elliptical distribution, so the value range of k is (-1, 0). Assuming k = -0.5, next, the value of c is obtained, which satisfies the following equation:

[0078]

[0079] r1(x, y) and r2(x, y) are respectively the maximum and minimum curvature radii at the surface (x, y) of the lens. Their calculations are as follows: r1 and r2 satisfy the two solutions of the following quadratic equation:

[0080]

[0081]

[0082] It is solved that c = 6.43. Eccentricity is determined for the face shape according to the distance d1 from the reference measurement point of the second refractive region to the geometric center, and the eccentricity distance is d1 = 12 mm. The sagittal height expression is as follows:

[0083]

[0084] Calculate the change in optical power D0(u) from the reference measurement point of the first refractive region of the conic surface to the reference measurement point of the second refractive region:

[0085]

[0086] Calculate the change in optical power D0(u) on the straight line from the reference measurement point of the first refractive region of the conic surface to the reference measurement point of the second refractive region:

[0087]

[0088] Determine the optical power change curve D(x) of the addition transition zone of the design surface. This curve describes the change in optical power from the reference measurement point of the first refractive region to the reference measurement point of the second refractive region. The expression of D(x) is:

[0089]

[0090] In the formula, m = 3, and the coefficients a1, a2, a3, and a4 are determined by the following system of equations:

[0091]

[0092] In the formula, k0 is a variable that controls the change speed of the optical power at the corresponding position. Here, k0 = 0.02, and the solved coefficient values are:

[0093] Coefficient a1 a2 a3 a4 Value 3.21 -2.38 -0.24 0.03

[0094] Then the optical power change curve of the superimposed progressive multifocal face shape in this region is:

[0095]

[0096] Map the optical power on this curve to the entire surface through a curve cluster. Each curve in the curve cluster intersects with the optical angle change curve, and the optical power value on each curve is equal to the optical power value at the intersection point, thereby obtaining the optical power distribution D p (x,y),

[0097]

[0098] The curvature radius distribution of the corresponding points on the lens is obtained from the dioptric power distribution, and the calculation formula is:

[0099]

[0100] The calculation formula for the center of curvature corresponding to each curvature radius is:

[0101]

[0102] A series of circles are constructed with the curvature radius and the corresponding center of curvature coordinates. The envelope surface of these circles is the surface of the lens, and its sagittal height z p (x, y) is:

[0103]

[0104] The expression of the sagittal height of the final designed surface is:

[0105] z(x, y) = z + z p (x, y).

[0106] After calculation, the dioptric power distribution and astigmatism distribution of the designed surface of the lens are obtained.

[0107] The anti-fatigue lens obtained with the same lens design parameters by adopting the technical solution disclosed in CN201909909 U is used as the comparative example.

[0108] See Appendix Figure 2 、 3 , which are respectively the schematic diagrams of the dioptric power distribution and astigmatism distribution of the lens of the comparative example.

[0109] See Appendix Figure 4 、 5 , which are respectively the schematic diagrams of the dioptric power distribution and astigmatism distribution of the designed surface of the lens provided in this embodiment. Figure 4 It can be seen that the dioptric power in the reading area of the lens (8 - 14 mm below the geometric center) increases slightly. The dioptric power in the reading area of the lens increases slightly by 0.25 D, avoiding the stable fixation area formed in the comparative example, that is, a stable dioptric power is formed within the reading area; it can be seen from Figure 5 that the maximum astigmatism value within 20 mm of the optical center of the glasses is 0.12 D, which is less than 0.25 D; the maximum astigmatism of the comparative example is 0.628 D.

[0110] The mold for preparing the universal anti-fatigue spectacle lens designed in this embodiment is formed by clamping an upper mold base and a lower mold base. The upper mold base has a concave surface for forming the front surface of the spectacle lens, and the lower mold base has a convex surface for forming the rear surface of the spectacle lens; the mold is a glass mold or a metal mold.

[0111] Example 2

[0112] In this example, the design parameters are the same as those in Example 1. The difference is that the initial surface shape of the design surface adopts a hyperbolic form, so the k value is taken as -2.56. Through the same calculation method, the c value is obtained as 3.68.

[0113] Calculate the change in optical power D0(u) on the straight line from the reference measurement point in the first refractive region of the quadric surface to the reference measurement point in the second refractive region:

[0114]

[0115] Adopt the optical power change curve D(x) of the same design surface's add-power transition zone.

[0116] Then the optical power change curve of the superimposed progressive multifocal surface shape in this region is:

[0117]

[0118] The sagittal height of the superimposed progressive multifocal surface is calculated as:

[0119]

[0120] The expression of the sagittal height of the final design surface is:

[0121] z(x,y)=z+z p (x,y)

[0122] After calculation, the optical power distribution and astigmatism distribution diagram of the lens design surface are obtained, as shown in Figure 6 and Figure 7 shown: It can be seen from the figure that the astigmatism value within 20 mm of the fitting center is 0.06 D, which is less than 0.25 D; the optical power in the reading area of the lens increases slightly by 0.25 D, avoiding the formation of a stable fixation area.

[0123] Example 3

[0124] In this example, the design parameters are the same as those in Example 1. The difference is that the initial surface shape of the design surface adopts a parabolic form, so the k value is taken as -1. Through the same calculation method, the c value is obtained as 5.43.

[0125] Calculate the change in optical power D0(u) on the straight line from the reference measurement point in the first refractive region of the quadric surface to the reference measurement point in the second refractive region:

[0126]

[0127] Adopt the optical power change curve D(x) of the same design surface's add-power transition zone.

[0128] The dioptric power change curve of the superimposed progressive multifocal surface profile in this region is as follows:

[0129]

[0130] The sagittal height of the superimposed progressive multifocal surface is calculated to be:

[0131]

[0132] The expression of the sagittal height of the final designed surface is:

[0133] z(x,y) = z + z p (x,y)

[0134] After calculation, the dioptric power distribution and astigmatism distribution maps of the lens designed surface are obtained, as Figure 8 and Figure 9 shown: It can be seen from the figure that the maximum astigmatism within 20 mm of the fitting center is 0.12 D, which is less than 0.25 D; the dioptric power in the reading area of the lens increases slightly by 0.25 D, avoiding the formation of a stable fixation area.

[0135] The results of the above three embodiments of the present invention prove that, compared with the lenses with anti-fatigue design provided by the prior art, a general anti-fatigue lens proposed by the present invention can effectively reduce peripheral astigmatism, while the dioptric power in the reading area changes slightly, avoiding the formation of a stable fixation area, and to a certain extent avoiding the defect of the contradiction between convergence and accommodation of exophoria people caused by long-term use of the reading area for fixation in traditional anti-fatigue lenses.

Claims

1. A universal anti-fatigue spectacle lens, characterized in that: It includes a first refractive region located above the lens, a second refractive region located below the lens, and a progressive addition transition zone connecting the two refractive regions; The first refractive region is an aspheric design for correcting refractive errors beyond 5 meters; the first refractive region includes a distance reference measurement point and a distance aspheric compensation value reference point. The distance reference measurement point is within 0-8 mm above the geometric center of the lens; the distance aspheric compensation value reference point is 15 mm vertically upward with the distance reference measurement point as the center. The aspheric compensation value at the distance aspheric compensation value reference point is 5%-10% of the optical power at the distance reference measurement point; The second refractive region is an aspherical design for relaxing accommodation and convergence during reading, including a near reference measurement point and an astigmatism measurement reference point. The near reference measurement point is within a range of 8 to 14 millimeters below the geometric center of the lens; the astigmatism measurement reference point coincides with the near reference measurement point, and the astigmatism value C0 at the astigmatism measurement reference point satisfies: C0 ≤ (C - C f ) / ADD × 70%, where C is the actual measured astigmatism value at the astigmatism measurement reference point, and C f is the prescribed astigmatism value; The progressive addition transition zone is a region of optical power change connecting the distance reference measurement point of the first refractive region and the near reference measurement point of the second refractive region. The optical power change amount ADD of the progressive addition transition zone satisfies: 0.25D ≤ ADD ≤ 0.60D; The fitting center of the lens is set on the progressive addition transition zone where the optical power change amount is 10%-20% ADD; The design method of the universal anti-fatigue spectacle lens includes the following steps: (1) Set a first refractive region on the lens, located above the lens, and a second refractive region below the lens; the first refractive region includes a distance reference measurement point and a distance aspheric compensation value reference point, and the second refractive region includes a near reference measurement point and an astigmatism measurement reference point; the region of optical power change connecting the distance reference measurement point of the first refractive region and the near reference measurement point of the second refractive region is the progressive addition transition zone; according to the refraction result, respectively determine the distances d1 and d2 from the distance reference measurement point of the first refractive region and the near reference measurement point of the second refractive region to the geometric center of the lens, the optical power D1 of the distance reference measurement point of the first refractive region, and the optical power change amount ADD of the progressive addition transition zone, and obtain the optical power D2 of the near reference measurement point of the second refractive region as D1 + ADD; (2) Take the initial surface shape with an aspheric surface as the design surface, and take the sag of the aspheric surface as the expression of the initial surface shape of the design surface. According to the parameters d1, d2, D1, and D2 obtained in step (1), calculate the quadratic surface parameters of the initial surface shape expression. The quadratic surface parameters include the basic curvature at the vertex and the conic constant; (3) Move the vertex of the initial surface shape to the distance reference measurement point with an eccentricity of d1, and perform eccentricity processing on the initial surface shape; (4) Use the differential geometry algorithm to obtain the optical power change D0(u) from the distance reference measurement point of the first refractive region to the near reference measurement point of the second refractive region of the initial surface shape; (5) The power variation curve D(u) of the addition transition zone with a third-order polynomial as the design surface is used to determine the power variation curve D P (u) of the addition transition zone of the stacked surface type, D P (u) = D(u) - D0(u); (6) Based on the dioptric power change curve D P (u) obtained in step (5), for the superimposed surface type with the progressive multifocal surface as the design surface, the curvature radius distribution of the surface of the superimposed surface type is obtained by using the contour line mapping method, and the sagitta of the superimposed surface type is calculated based on the curvature center coordinates corresponding to the curvature radius; (7) Superimpose the superimposed surface shape and the initial surface shape to obtain the sag of the design surface of a universal anti-fatigue spectacle lens; (8) Take the design surface obtained in step (7) as one surface of the lens, and the other surface is one of a spherical surface, a toric surface, or a freeform surface to obtain a universal anti-fatigue spectacle lens.

2. The general anti-fatigue spectacle lens according to claim 1, wherein: The peripheral optical power change and astigmatism change contour lines of the spectacle lens show a linear and unidirectional change from the distance reference measurement point downward and to the left and right sides.

3. A mold for preparing a universal anti-fatigue spectacle lens as claimed in claim 1, characterized in that: The mold is formed by clamping an upper mold base and a lower mold base. The upper mold base has a concave surface for forming the front surface of the spectacle lens, and the lower mold base has a convex surface for forming the rear surface of the spectacle lens; the mold is a glass mold or a metal mold.

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