Design method and design device for multi-point out-of-focus glasses lens

Abstract

The invention discloses a design method and a design device of a multi-point out-of-focus glasses lens. The design method is realized based on a curved surface substrate lens array splicing method, a spliced curved surface is formed by splicing a substrate curved surface and a sub-spherical surface array, after the vector height and the normal vector of the substrate curved surface at the sub-spherical surface position are determined, the expression of the sub-spherical surface is solved through the given curvature radius and aperture size, and the sub-spherical surface is obtained. And the vector height of the sampling point of the spliced curved surface is determined by comparing the local curvatures and vector heights of the substrate curved surface and the sub-spherical surface at any sampling point, so that the spliced curved surface with continuous functions and no sudden change at the boundary of the substrate curved surface and the sub-spherical surface is obtained, surface processing is facilitated, and the sub-spherical surface array can be arranged in a user-defined manner. And the curved surface parameters can be designed according to the required focal power of the substrate curved surface and the sub-spherical array. According to the design method, the curved surface description process is simple, the result is accurate, implementation is easy, and the obtained spliced curved surface is suitable for design and simulation analysis of multi-point out-of-focus glasses lenses.

Description

Technical Field

[0001] The invention relates to a design method for a multi-point defocused eyeglass lens and also to a corresponding design device, belonging to the field of multi-point defocused eyeglass lens design. Background Art

[0002] In the context of the current high incidence of myopia worldwide, myopia research has become the most concerned topic in the field of optometry. For people, once true myopia is formed, it cannot be reversed. If true myopia is not controlled and develops into high myopia, it will bring great health risks. Therefore, delaying the development of myopia has important clinical significance.

[0003] The function of general myopia lenses is only to correct the refraction of the central field of view, and there is hyperopic defocus in the peripheral field of view, which can easily lead to problems such as axial length growth and deepening of myopia. To address this problem, Hoya launched multi-zone positive optical defocus (DIMS: Defocus Incorporated Multiple Segments) eyeglass lenses in 2019, that is, multi-point defocus eyeglass lenses, and conducted long-term clinical trials. This lens can simultaneously achieve refractive correction and regional myopia defocus by setting 396 hexagonally arranged microlens arrays in the 32mm diameter area of ​​the center of the lens, and stimulate cone cells with myopic defocus light beams, thereby achieving the purpose of slowing down the deepening of myopia and slowing down the growth of the axial length. However, this type of lens is difficult to manufacture and expensive to process, and there is currently a lack of comprehensive analysis of its mechanism and result prediction. Summary of the invention

[0004] The primary technical problem to be solved by the present invention is to provide a design method for multi-point defocus eyeglass lenses.

[0005] Another technical problem to be solved by the present invention is to provide a design device for multi-point defocus eyeglass lenses.

[0006] In order to achieve the above technical objectives, the present invention adopts the following technical solutions:

[0007] According to one aspect of the present invention, a method for designing a multi-point defocused eyeglass lens is provided, including a process of constructing a spliced ​​curved surface γ using a curved surface base lens array splicing method, wherein the curved surface base lens array splicing method comprises the following steps:

[0008] Step 1: The spliced ​​surface γ can be divided into the base surface α and multiple sub-spheres β i , i is a positive integer, and the base surface α is generated according to the curvature and the quadratic coefficient, and is brought into each sub-sphere β i The position p i The coordinates in the XY plane (x i ,y i), calculate the position p of each sub-sphere i The vector height and first-order derivative of the base surface at the position p of the sub-sphere are determined from this i The normal vector f of the base surface at i , normal vector f i Use normalized vectors;

[0009] Step 2: Given the sub-sphere curvature radius r and its aperture radius h i , we can calculate the vector height Δs of each sub-sphere vertex away from the base surface i and the offset length d of the center of each sub-sphere away from the base surface along the normal vector i ; By the above offset length d i and the normal vector f described in step 1 i Calculate the subsphere β i The coordinates of the center of the sphere, and then find the sub-sphere β i Expression of

[0010] Step 3: For any sampling point, calculate the local curvature of the base surface α at the sampling point, and compare the base surface α with the sub-sphere β i The local curvature and sagitta at the sampling point determine the sagitta z(x,y) of the spliced ​​surface γ at the sampling point.

[0011] Preferably, in step 1, the base surface α uses a quadratic surface, and its specific expression is:

[0012]

[0013] Among them, c base represents the curvature, k base represents the quadratic coefficient, (x, y) is the coordinate on the base surface, z base (x,y) represents the base surface α;

[0014] The first derivative of the basis surface α and The expression is:

[0015]

[0016] in, is the simplified expression of the derivative of the basis surface α with respect to x, is the simplified expression of the derivative of the basis surface α with respect to y;

[0017] Subsphere β i The normal vector of the vertex is

[0018] Preferably, in step 2, the offset length d i The expression is:

[0019]

[0020] Subsphere β i The coordinates of the center of the sphere (x ci ,y ci ,z ci ) can be expressed as:

[0021] (x ci ,y ci z ci )=(x i ,y i ,z i )-d i f i ,

[0022] Among them, (x i ,y i ,z i ) is the i-th subsphere β i The position p i The coordinates of

[0023] The sub-sphere β i It can be expressed as:

[0024]

[0025] Preferably, in step 3, the base surface α is a rotationally symmetric surface, and its local curvature c at point (x, y) is base (ρ) is expressed in radial coordinate ρ as:

[0026]

[0027] Subsphere β i The curvature c is expressed as:

[0028] Preferably, in step 3, for any sampling point, the sub-sphere β i The local curvature c i is equal to the curvature c of the sub-sphere. When the sub-sphere β i When the local curvature of the base surface α is of different sign, the splicing surface γ can be expressed as:

[0029]

[0030] When the subsphere β i When the local curvature of the subsphere β is of the same sign as the local curvature of the base surface α, i The local curvature c i Greater than the local curvature c of the base surface α base , the splicing surface γ can be expressed as:

[0031]

[0032] When the subsphere β i When the local curvature of the subsphere β is of the same sign as the local curvature of the base surface α, i The local curvature c i Less than the local curvature c of the base surface α base , the splicing surface γ can be expressed as:

[0033]

[0034] Preferably, step 3 includes the following sub-steps: calculating the local curvature of any sampling point of the base surface α, and calculating the local curvature of the base surface α and the adjacent sub-spheres β at the sampling point. i The local curvature and vector height of the sampling point are used to determine whether the sampling point belongs to the base surface α. If so, the vector height of the base surface α is used as the vector height at the sampling point. Otherwise, the vector height of the base surface α is combined with the adjacent multiple sub-spheres β. i The local curvature and sagitta of are used to obtain the sagitta of the spliced ​​surface γ at the sampling point.

[0035] Preferably, the design process of designing a multi-point defocus eyeglass lens using the curved substrate lens array splicing method comprises the following steps:

[0036] Step 101: The curvatures of the front and back surfaces of the base lens are adjusted according to the required corrective diopter D. c design;

[0037] Step 102: The sub-spherical surface takes the front surface S1 of the base lens as the base curved surface, and the curvature of the sub-spherical surface is determined according to the required myopia defocus diopter D. sub design;

[0038] Step 103: In a curved surface coordinate system with the base curved surface as the coordinate axis, generate the arrangement points q of the sub-spherical array on the base curved surface according to the required arrangement method. i , map the coordinates of the arrangement points from the curved coordinate system to the plane perpendicular to the Z axis in the rectangular coordinate system, and obtain the sub-sphere β i The position p i Coordinates in the XY plane;

[0039] Step 104, combining the curved surface base lens array stitching method to obtain the stitching curved surface γ, and using the stitching curved surface γ as the front surface of the multi-point defocus eyeglass lens, and using the back surface of the base lens as the back surface of the multi-point defocus eyeglass lens, to generate the multi-point defocus eyeglass lens.

[0040] Preferably, in step 101, the glasses are regarded as thin lenses, and the corrected diopter D c The expression is:

[0041]

[0042] Wherein, f represents the focal length of the base lens, n2 represents the refractive index of the base lens material, n1 represents the refractive index of air, R1 represents the curvature radius of the front surface S1 of the base lens, and R2 represents the curvature radius of the back surface S2 of the base lens.

[0043] Preferably, in step 102, the myopic defocus diopter D sub The expression is:

[0044]

[0045] Where r represents the radius of curvature of the sub-sphere.

[0046] Preferably, in step 103, the process of mapping the arrangement point coordinates from the curved surface coordinate system to the coordinates in the XY plane in the rectangular coordinate system uses the following mapping expression:

[0047]

[0048] Among them, (x i_suf ,y i_suf ) represents the front row of points q i Coordinates in the surface coordinate system, (x i ,y i ) represents the subsphere β after mapping i The position p i Coordinates on the XY plane in rectangular coordinates.

[0049] According to a second aspect of the present invention, there is provided a design device for a multi-point defocus eyeglass lens, for implementing the above-mentioned design method, comprising:

[0050] The base lens curvature generating unit is configured to correct the diopter D according to the required diopter D c Designing the curvature of the front and back surfaces of the base lens;

[0051] The sub-spherical curvature generating unit is configured to generate a sub-spherical curvature according to the required myopia defocus diopter D sub The curvature of the sub-spherical surface is designed, and the sub-spherical surface takes the front surface S1 of the base lens as the base curved surface;

[0052] The sub-spherical surface position generating unit is configured to generate the arrangement points q of the sub-spherical surface array on the base curved surface in the curved surface coordinate system with the base curved surface as the coordinate axis according to the required arrangement mode. i , and map the coordinates of the arrangement points from the curved coordinate system to the XY plane of the rectangular coordinate system to obtain the sub-sphere β i The position p i The coordinates in the XY plane (x i,y i );

[0053] A splicing curved surface profile description unit, configured to generate the splicing curved surface γ according to the curved surface base lens array splicing method; and

[0054] The multi-point defocus eyeglass lens generating unit is configured to use the splicing curved surface γ as the front surface of the multi-point defocus eyeglass lens and use the back surface of the base lens as the back surface of the multi-point defocus eyeglass lens to generate the multi-point defocus eyeglass lens.

[0055] According to a third aspect of the present invention, there is provided a computer-readable storage medium, on which a computer program is stored, and the computer program is used to enable a computer to execute the above-mentioned multi-point defocus eyeglass lens design method.

[0056] According to a fourth aspect of the present invention, there is provided an electronic device comprising at least a processor and a memory, wherein the memory stores a computer program, and when the processor executes the computer program, the multi-point defocus eyeglass lens design method is implemented.

[0057] The optical design method of the multi-point defocused eyeglass lens provided by the present invention is implemented based on the curved surface base lens array splicing method. The spliced ​​surface can be generated by the curved surface base lens array splicing method, wherein the spliced ​​surface uses a quadratic surface as a base, and splices a sub-spherical array on the quadratic surface. After determining the position point and normal vector of the sub-spherical surface on the base surface, the expression of the sub-spherical surface is obtained by the curvature radius and aperture size given by the sub-spherical surface, and the sagittal height at any sampling point in the spliced ​​surface is determined by comparing the local curvature and sagittal height of the base surface and the sub-spherical surface at the sampling point, thereby obtaining a surface shape with continuous functions and no mutations at the boundary between the base surface and the sub-spherical surface. The spliced ​​surface obtained by this design method is conducive to the processing of the lens surface, wherein the sub-spherical array can be custom arranged, and the parameters of the spliced ​​surface can be designed according to the required focal length of the base surface and the focal length of the sub-spherical surface. The surface description method in the present invention is simple, accurate, and easy to implement. The obtained spliced ​​surface is suitable for the design of multi-point defocused eyeglass lenses that require special lens arrays. By generating the arrangement points of the lens array in a surface coordinate system with the base surface as the coordinate axis, the arrangement of the lens array is freed from the limitation of a fixed plane, and its arrangement mode can be customized to meet more application scenarios. The design method provides a complete design idea for multi-point defocused eyeglass lenses and is conducive to the simulation analysis of the optical indicators of multi-point defocused eyeglass lenses. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Figure 1 A flow chart of the curved substrate lens array splicing method provided by the present invention;

[0059] Figure 2 The schematic diagram is a diagram showing the expression determined by the radius of curvature of the sub-sphere and the aperture size;

[0060] Figure 3 It is a schematic diagram of determining the sagittal height of any sampling point of the spliced ​​surface by comparing the local curvature and sagittal height of the base surface and the sub-sphere surface;

[0061] Figure 4 It is a schematic diagram of single-view myopia glasses lens and human eye model in optical simulation software;

[0062] Figure 5 A flow chart of the multi-point defocus eyeglass lens design method provided by the present invention;

[0063] Figure 6(a) , 6(b) and 6(c) are schematic diagrams of the arrangement of three types of seed spherical arrays on the base surface;

[0064] Figure 7 Schematic diagram of mapping the sub-spherical array position from the curved coordinate system to the rectangular coordinate system XY plane;

[0065] Figure 8 A schematic diagram of modeling a multi-point defocusing eyeglass lens using an annular defocusing lens;

[0066] Fig. 9 A schematic diagram of the multi-point defocused glasses lens and the human eye model provided by the present invention in optical simulation software;

[0067] FIG10( a ) and FIG10( b ) are comparisons of the MTF simulation results of a single-viewpoint eyeglass lens and a multi-point defocus eyeglass lens, respectively;

[0068] FIG11( a ) and FIG11( b ) are comparisons of wavefront errors of single-viewpoint eyeglass lenses and multi-point defocus eyeglass lenses at different fields of view, respectively;

[0069] Figure 12(a) , 12(b) , 12(c) and 12(d) are two-dimensional image simulation comparisons of single-viewpoint eyeglass lenses and multi-point defocus eyeglass lenses, respectively;

[0070] Fig.13 It is a hardware architecture diagram of an electronic device provided by the present invention;

[0071] Fig.14 It is a structural diagram of a design device for a multi-point defocused eyeglass lens provided by the present invention. DETAILED DESCRIPTION

[0072] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0073] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0074] The multi-point defocus eyeglass lens provided by the present invention comprises: a base lens, which mainly bears the function of making the light beam incident from the surface on the object side be emitted from the surface on the eyeball side and converged to the retina through the eyeball; and, a plurality of microlenses arranged on the base lens, wherein the microlenses are defocused areas connected to the surface of the base lens, and a microlens array composed of a plurality of microlenses mainly bears the function of making the light beam incident from the surface on the object side be emitted from the surface on the eyeball side and converged to the front or back side of the retina through the eyeball. When the light converges on the front side of the retina after defocusing and irradiates the retina in a divergent form, it corresponds to myopia defocus, which is used for myopia prevention and control; when the light irradiates the retina in a convergent form after defocusing and converges to the back side of the retina, it corresponds to hyperopia defocus, which is suitable for treating hyperopia patients. The present invention focuses on describing the design method of multi-point defocus eyeglass lenses for myopia defocus, but it cannot exclude the application of the design method to the design of hyperopia defocus lenses, the difference being that the refractive power of the lens array used therein is different. The base lens is a portion that can realize the prescribed refractive power of the wearer from the perspective of geometric optics. The microlens array is a region where at least a portion of the region does not focus light to the focusing position based on the base lens from the perspective of geometric optics.

[0075] The design method of the multi-point defocus eyeglass lens provided by the present invention is implemented based on the curved surface base lens array splicing method. The spliced ​​surface can be obtained by the curved surface base lens array splicing method, and the spliced ​​surface uses a quadratic surface as the base surface, and splices a sub-spherical array on the quadratic surface. The surface shape of the spliced ​​surface is described using the spliced ​​quadratic surface and the sub-spherical array, and the vector height of the spliced ​​surface at any sampling point is determined by calculating and comparing the local curvature and vector height of the base surface and the sub-spherical surface, thereby obtaining a surface shape with continuous functions and no mutations at the boundary between the microlens array and the base surface. The above-mentioned design method of the multi-point defocus eyeglass lens is used to simulate the multi-point defocus eyeglass lens, and this type of surface shape can be directly expressed in mathematical form in optical simulation software (for example, CODEV, ZEMAX, LIGHTTOOLS, VIRTUALLAB FUSION, etc.), thereby realizing the simulation and testing of the multi-point defocus eyeglass lens.

[0076] The design method and device for the multi-point defocus eyeglass lenses provided by the present invention are described in detail below in conjunction with the accompanying drawings.

[0077] Design methods for multi-point defocus eyeglass lenses, including Figure 1 The curved surface base lens array stitching method shown is used to generate a stitched surface. The curved surface base lens array stitching method includes the following steps: Step 1: Generate a base surface, bring the coordinates of each sub-spherical position in the sub-spherical array point in the XY plane into the base surface, calculate the sag and surface normal vector of the base surface at the sub-spherical position, and determine the direction of the sub-spherical vertex by the normal vector; Step 2: Given the curvature radius and aperture size of the sub-spherical surface, calculate the vertex and sphere center coordinates of each sub-spherical surface according to its direction, and then obtain the expression of the sub-spherical surface; Step 3: Calculate the local curvature of the base surface at any sampling point, and obtain the sag of the stitched surface at the sampling point according to the local curvature and sag of the base surface and the sub-spherical surface at the sampling point.

[0078] Furthermore, in the above process, the sub-spherical array points are discretely distributed, and adjacent sub-spherical surfaces can be separated from each other on the base surface, or some sub-spherical surfaces can be gathered, so that there is a connecting area that belongs to two or more adjacent sub-spherical surfaces at the same time; how to determine the vector height of the sampling point in the connecting area requires comparing the local curvature and vector height of the base surface at the sampling point position and the adjacent multiple sub-spherical surfaces. Specifically, the above step 3 can also include the following sub-steps: calculate the local curvature of any sampling point on the base surface, and determine whether the sampled point belongs to the base surface based on the local curvature and vector height of the base surface and the adjacent multiple sub-spherical surfaces; if so, use the vector height of the base surface as the vector height of the splicing surface at this point; otherwise, calculate the vector height of the adjacent multiple sub-spherical surfaces at this point, and combine the local curvature and vector height of the adjacent multiple sub-spherical surfaces to determine the vector height of the splicing surface at the sampling point.

[0079] Specifically, quadratic surfaces have rotational symmetry, high machining accuracy, and can ideally image near-axial incident light in a variety of situations. Due to the large spherical aberration of spherical surfaces, some optical descriptions of eyeglass lenses now use quadratic surfaces or aspherical surfaces. Many special surface types use quadratic surfaces as base surfaces, such as the commonly used XY polynomial free-form surfaces, Zernike polynomial free-form surfaces, etc. The optical description equation of a quadratic surface can be expressed as:

[0080]

[0081] Among them, c is the curvature of the surface vertex, k is the quadratic surface constant, and (x, y) are the coordinates of the surface point.

[0082] The spliced ​​surface obtained by the splicing method of the curved surface base lens array provided by the present invention is formed by arranging a sub-spherical array on a surface of a quadratic surface as a base surface. However, directly splicing the sub-spherical surface on the surface cannot ensure the continuity of the surface. The sudden change of the surface will increase the difficulty of processing and reduce the optical performance of the optical description. Therefore, it is necessary to make reasonable constraints on the sub-spherical surface to construct a continuously spliced ​​lens array. The construction process is as follows: Figure 2 As shown, the following steps are included:

[0083] Step 1: The spliced ​​surface γ can be divided into the base surface α and multiple sub-spheres β i , i is a positive integer, and the base surface α is generated according to the curvature and the quadratic coefficient, and is brought into each sub-sphere β i The position p i The position coordinate (x i ,y i ), calculate each sub-sphere β i Position p i The value z and the first derivative of the basis surface at And thus determine the position p of the sub-sphere i The normal vector f of the base surface at i , the normal vector is also the normal vector of the vertex of the sub-sphere, the normal vector f i Use the normalized vector. Among them, the subsphere β i The position p i The position coordinate (x i ,y i ) and the sub-sphere arrangement points q generated according to the required array arrangement mode i There is a mapping relationship between the coordinates in the surface coordinate system, and the two satisfy the triangular mapping relationship. i The position p i The values ​​are:

[0084]

[0085] Among them, c base is the curvature of the base surface, k base is the quadratic coefficient of the base surface, (x, y) is the coordinate on the base surface, z base (x,y) represents the base surface α;

[0086] Its first-order derivative and The expression is:

[0087]

[0088] in, is the simplified expression of the derivative of the basis surface α with respect to x, is a simplified expression for the derivative of the basis surface α with respect to y.

[0089] like Figure 2 As shown in the figure, in order to obtain a sub-sphere that is continuous with the base surface while determining the diameter radius of the sub-sphere, the normal vector of the base surface needs to be used as the local coordinate axis of the sub-sphere. For the sub-sphere array, the normal vector of the base surface needs to be solved for each position point, while for the annular defocused surface, only the normal vector of the base surface needs to be solved for one point in the same radial coordinate. For example, for (0,y i ) points. The subsequent parameter solutions of the annular defocusing surface and the sub-spherical array are similar, and the only difference is the form of the expression.

[0090] like Figure 2 As shown, the direction of the normal vector is defined as the negative direction of the Z axis, and the normal vector f i It can be expressed as:

[0091]

[0092] In the subsequent description, the normal vector used by default is the result of vector normalization.

[0093] Step 2, since the sub-sphere position p i The normal vector f of the base surface at i It has been determined that when the curvature radius r of the sub-sphere and the aperture radius h i After being defined, the coordinates of the sphere center and the vertex positions can be determined. Figure 2 As shown, the vector height Δs of each sub-sphere vertex away from the base can be calculated i and the offset length d of the center of each sub-sphere from the base i ; By the above offset length d i and the normal vector f described in step 1 iCalculate the subsphere β i The coordinates of the center of the sphere are obtained, and then the expression of the sub-sphere is obtained. The offset length d i The expression is:

[0094]

[0095] The coordinates of the center of the sphere (x ci ,y ci ,z ci ) can be expressed as:

[0096] (x ci ,y ci ,z ci )=(x i ,y i ,z i )-d i f i (6)

[0097] Among them, (x i ,y i ,z i ) is the i-th subsphere β i The position p i The coordinates of (x ci ,y ci ,z ci ) represents the i-th subsphere β i The coordinates of the center of the sphere;

[0098] The sub-sphere β i It can be expressed as:

[0099]

[0100] From the above calculation process, we can know that the sub-sphere β i The position p i is the intersection point of the line connecting the vertex of each sub-sphere and the center of the sphere and the base surface α, and the sub-sphere β i The position p i The coordinates in the XY plane (x i ,y i ) is obtained by referring to the generation and coordinate transformation process of the sub-sphere array points below. i The position p i The coordinates in the XY plane (x i ,y i ), combined with the surface shape expression of the base surface α, calculate the sub-sphere β i The position p i The height loss z of the base surface α at i , we can calculate the sub-sphere β i The position pi The coordinates (x i ,y i ,z i ).

[0101] Step 3: When the base is a quadratic surface, it will no longer have rotational symmetry when it leaves the Z axis. Since the sub-sphere surface needs to satisfy the constraint of continuity between the sub-sphere surface and the base surface, the aperture of the sub-sphere spliced ​​on the quadratic surface will not be a standard circle. If the sub-sphere surface obtained in step 2 is directly spliced ​​with the base surface with the designed aperture of the sub-sphere surface as the constraint, a mutation will occur at the surface connection. This method determines the sag of the sampling point of the spliced ​​surface by comparing the local curvature and sag of the base surface and the sub-sphere surface point by point, and can accurately depict the aperture profile of the sub-sphere surface.

[0102] The base surface α is a rotationally symmetric surface, and its local curvature c at the sampling point (x, y) is base (ρ) is expressed in radial coordinate ρ as:

[0103]

[0104] The curvature c of the sub-sphere can be expressed as:

[0105]

[0106] For any sampling point, the local curvature c of the sub-sphere is i is equal to the curvature c of the sub-sphere. When the sub-sphere β i When the local curvature of and the local curvature of the base surface α have different signs, the splicing surface γ can be expressed as:

[0107]

[0108] When the subsphere β i When the local curvature of has the same sign as the local curvature of the base surface α, the local curvature of the sub-sphere will affect the value of the splicing surface. Figure 3 As shown in the left figure, when the sub-sphere β i The local curvature c i Greater than the local curvature c of the base surface α base , the splicing surface γ can be expressed as:

[0109]

[0110] like Figure 3 As shown in the figure on the right, when the sub-sphere β i The local curvature c i Less than the local curvature c of the base surface α base , the splicing surface γ can be expressed as:

[0111]

[0112] By comparing the local curvature and sagitta of the base surface and the sub-sphere at any sampling point, the sagitta of the sampling point in the spliced ​​surface is determined. When a sampling point may belong to two or more adjacent sub-spheres at the same time, the local curvature and sagitta of the base surface and multiple sub-spheres at the sampling point are obtained by calculation, and the local curvature and sagitta of the base surface and multiple sub-spheres at the sampling point are compared based on the above judgment logic to obtain the sagitta of the sampling point, thereby accurately describing the surface shape of the spliced ​​surface.

[0113] The following examples illustrate the application process and beneficial effects of the curved substrate lens array splicing method in the optical design of multi-point defocused eyeglass lenses. By using the curved substrate lens array splicing method to optically describe the surface of a multi-point defocused eyeglass lens as an example, the feasibility of the curved substrate lens array splicing method is verified, and the reliability of the spliced ​​curved surface simulated multi-point defocused eyeglass lenses obtained by using the curved substrate lens array splicing method is verified.

[0114] like Figure 4 The figure shows a simulation model of a single-view myopia glasses with a human eye model. The simulation model includes a convex-concave lens L as myopia glasses and a myopic human eye model E. The single-view myopia glasses lens is obtained by establishing a base lens model using the parameters of the base lens. In the simulation test process of the multi-point defocus glasses lens below, the single-view myopia glasses lens is used as a comparative example to evaluate the simulation results of the multi-point defocus glasses lens.

[0115] Figure 5 The method for designing a multi-point defocused eyeglass lens provided by the present invention is shown, and the multi-point defocused eyeglass lens is designed by using the above-mentioned curved substrate lens array splicing method, comprising the following steps:

[0116] Step 101, taking an ideal thin lens as an example, the curvature of the base lens is determined according to the required corrective diopter D c Optically described, the expression of the corrected diopter is:

[0117]

[0118] Wherein, f represents the focal length of the base lens, n2 represents the refractive index of the base lens material, n1 represents the refractive index of air, R1 represents the curvature radius of the front surface S1 of the base lens, and R2 represents the curvature radius of the back surface S2 of the base lens.

[0119] The human eye model used has +3.0D emmetropia defocus, which corresponds to the corrected diopter of the glasses D. c = -3.0 D. The optimization results show that the curvature radii of the front surface S1 and the back surface S2 of the base lens are R1 = 798 mm and R2 = 173.1 mm.

[0120] Step 102: The sub-spherical surface uses the front surface S1 of the base lens as the base curved surface, and the curvature is based on the required myopia defocus diopter D. sub Optical description. The expression of the myopic defocus diopter is:

[0121]

[0122] Where r represents the radius of curvature of the sub-sphere. The myopic defocus diopter is selected as +3.5D. Since R2 has been determined by the optimization in step 101, r has a unique solution, and the solution is r=91 mm.

[0123] Step 103: In a curved surface coordinate system with the base curved surface as the coordinate axis, generate the arrangement points q of the sub-spherical array on the base curved surface according to the required arrangement method. i , the arrangement point q i Coordinate (x i_surf ,y i_surf ) is mapped from the curved surface coordinate system to the plane perpendicular to the Z axis in the rectangular coordinate system, and the sub-sphere β is obtained. i The position p i The coordinates in the XY plane (x i ,y i ), the subscript i of the corresponding coordinates before and after mapping has the same value, i represents the sequence number of the arrangement point in the sub-sphere array, which is a positive integer.

[0124] Specifically, Figure 7 As shown, a curved surface coordinate system is established with the base curved surface α as the coordinate axis, and the coordinate axis is distributed along the base curved surface α. The arrangement points q of the sub-spherical array on the base curved surface are generated according to the required arrangement method. i . A variety of sub-spherical arrays can be generated: hexagonal (see Figure 6(a)), rectangular (see Figure 6(b)), tangentially closely arranged circular (see Figure 6(c)), radially closely arranged circular, etc. The sub-spherical array takes the hexagonal arrangement shown in Figure 6(a) as an example, with an aperture of 1mm, a lens spacing of 1.5mm, and is arranged in a circular area with a diameter of 36mm. There is no sub-spherical arrangement in the circular area with a central diameter of 9mm.

[0125] Arrange points q on the sub-sphere i The coordinates are mapped from the curved surface coordinate system to the horizontal plane perpendicular to the Z axis in the rectangular coordinate system (i.e., the XY plane), and the position p of each sub-sphere is obtained. i Coordinates in the XY plane. The mapping expression used is:

[0126]

[0127] Among them, (x i_surf ,y i_surf) represents the arrangement point q in the surface coordinate system before mapping i The coordinates of (x i ,y i ) represents the position p of the sub-sphere after mapping i Coordinates in the XY plane.

[0128] by Figure 7 The multiple arrangement points q shown i For example, the purpose of generating sub-sphere arrangement points in the base surface coordinate system is to ensure that each arrangement point (such as Figure 7 The q1, q2, q3, q4, q5) shown in the figure are evenly distributed on the base surface α, that is, each point (x i_surf ,y i_surf ) are equal in length, and then the radian angle is obtained from the local curvature radius R1 of the base surface α through the above mapping expression (18). Finally, the actual coordinate value (x i ,y i ).

[0129] As attached Figure 8 As shown, in addition to the array arrangement, the above surface representation method can also be applied to the optical description of the annular defocused surface spliced ​​with the base surface. By modifying the sub-spherical surface expression in step 2, a multi-segment annular surface can be obtained. The sub-annular surface can be expressed as:

[0130]

[0131] Among them, l i Represents the distance from each sub-annulus to the center of the base surface.

[0132] In addition to the sub-spherical array points arranged in a regular manner as shown in the attached figure, the above design method is also applicable to the design of irregularly arranged sub-spherical array points. By customizing the sub-spherical array points in the curved coordinate system, and converting from the curved coordinate system to the rectangular coordinate system, the coordinates of the position of each sub-spherical surface in the XY plane are obtained, and then the curved base lens array splicing method is used to calculate the spliced ​​surface, so that the distribution of the sub-spherical array points is more in line with the surface characteristics of the base surface, with higher flexibility and meeting more application scenarios.

[0133] Step 104, based on the curvature radii R1 and R2 of the front surface S1 and the back surface S2 of the lens determined in step 101, the curvature radius r of the sub-spherical surface determined in step 102, and the curvature radius of each sub-spherical surface β determined in step 103, i The position p iIn the coordinates of the XY plane, a spliced ​​surface γ is obtained by combining the curved surface base lens array splicing method, and the spliced ​​surface γ is used as the front surface of the multi-point defocus eyeglass lens, and the back surface of the base lens is used as the back surface of the multi-point defocus eyeglass lens to generate a multi-point defocus eyeglass lens.

[0134] As attached Fig. 9 As shown, a multi-point defocused spectacle lens is generated in combination with a special face shape, and a myopic human eye model E is placed 12 mm behind it for reception and analysis. Using the multi-point defocused spectacle lens L1 obtained by the above design method, a lens array is added to the front surface S1 of the myopic glasses, so that the light passing through the base can be focused on the retina as usual, while the light passing through the sub-spherical part can be focused in advance. The point spread function (PSF), wavefront error, modulation transfer function (MTF) and two-dimensional image simulation results of the device can be quickly obtained through the analysis function of the optical simulation software.

[0135] As shown in Figures 10(a) and 10(b), the modulation transfer function (MTF) of the edge field of view calculated in the optical design software shows that the contrast of ordinary single-view glasses is greater than 0.5 at 15 line pairs, while the contrast of DIMS lenses drops to 0.25 at 15 line pairs, which is the most obvious drop compared to other line pairs. From the results, it can be seen that multi-point defocus glasses will cause a certain decrease in visual clarity, and the drop is most significant at medium resolution.

[0136] The wavefront errors of the single-view glasses and the multi-point defocus glasses in different fields of view were calculated in the optical simulation software. As shown in Figure 11(a), the average wavefront error of the single-view glasses at 549.8nm is 1.0579λ, and as shown in Figure 11(b), the average wavefront error of the multi-point defocus glasses at 549.8nm is 1.1575λ. The optical description results show that the multi-point defocus glasses will deteriorate the image quality, but the relative change is not large.

[0137] The 2D image simulation results can quickly and realistically reflect the visual effect of human eyes wearing the glasses. The 2D image simulation of ordinary single-view glasses and multi-point defocus glasses is performed, and the results shown in Figures 12(a) and 12(b) are obtained. Figures 12(c) and 12(d) are magnified images of the local areas in Figures 12(a) and 12(b), respectively. Figure 12(c) and 12(d) It can be seen that multi-point defocus glasses will cause the images to be blurred and partially distorted, and the image quality will be reduced. When optically describing the forward defocus vision, two-dimensional image simulation can provide a basis for selecting the appropriate forward defocus vision, without excessive defocus vision affecting the visual experience after wearing, or even affecting the health of myopic eyes.

[0138] From the above simulation analysis results, it can be seen that the curved substrate lens array splicing method can simulate multi-point defocus glasses lenses very well, and can be directly analyzed in optical simulation software. The spliced ​​surface obtained by the curved substrate lens array splicing method has continuous functions at the boundary between the substrate and the sub-spherical surface, without mutations, which is conducive to surface processing, can reduce the generation of stray light, and is more in line with the surface shape of multi-point defocus glasses lenses. The above multi-point defocus glasses design method can facilitate the processing and simulation analysis of multi-point defocus glasses, and is convenient and concise, with strong applicability. For other optical devices that require special microlens arrays, this description method can be used without a large amount of complex modeling to improve efficiency.

[0139] like Fig.13 , Fig.14 As shown, an embodiment of the present invention provides an optical design device for multi-point defocus eyeglass lenses. The device embodiment can be implemented by software, or by hardware or a combination of software and hardware. From the hardware level, Fig.13 FIG. 1 is a hardware architecture diagram of an electronic device in which an optical design device for a multi-point defocused eyeglass lens provided by an embodiment of the present invention is located. Fig.13 In addition to the processor, memory, network interface, and non-volatile memory shown, the electronic device in the embodiment may also include other hardware, such as a forwarding chip responsible for processing messages, etc. Taking software implementation as an example, Fig.14 As shown, as a device in a logical sense, the CPU of the electronic device in which it is located reads the corresponding computer program in the non-volatile memory into the internal memory and runs it.

[0140] like Fig.13 As shown, the optical design device of a multi-point defocused eyeglass lens provided in this embodiment includes:

[0141] The base lens curvature generating unit 10 is configured to generate a base lens curvature according to the required correction diopter D c Designing the curvatures of the front surface S1 and the back surface S2 of the base lens;

[0142] The sub-spherical curvature generating unit 20 is configured to generate a sub-spherical curvature according to the required myopia defocus diopter D sub The curvature of the sub-spherical surface is designed, and the sub-spherical surface takes the front surface S1 of the base lens as the base curved surface;

[0143] The sub-spherical array arrangement point generating unit 30 is configured to generate the arrangement points q of the sub-spherical array on the base curved surface in a curved surface coordinate system with the base curved surface as the coordinate axis according to the required arrangement mode. i , and map the coordinates of the arrangement points from the curved coordinate system to the XY plane of the rectangular coordinate system to obtain the sub-sphere β i The position pi The coordinates in the XY plane (x i ,y i ). For example, by generating the arrangement points of the sub-spherical array according to the desired arrangement, a curved base lens array with multiple arrangement modes can be generated: hexagonal, radially closely arranged circular, tangentially closely arranged circular, rectangular, etc. In addition, in addition to the array arrangement, the multi-point defocused eyeglass lens design device can also be used to design defocused eyeglass lenses with annular defocus surfaces. Moreover, the multi-point defocused eyeglass lens design device can also be used to design multi-point defocused eyeglass lenses with irregularly arranged defocus array points, wherein the arrangement mode of the sub-spherical array can be customized.

[0144] The splicing surface description unit 40 is configured to generate a splicing surface γ according to the surface base lens array splicing method, specifically including: generating a base surface α according to the curvature and the quadratic coefficient, bringing in each sub-spherical surface β generated according to the required array arrangement mode i The position p i In the coordinates in the plane perpendicular to the Z axis, the vector height and first-order derivative of the base surface at each sub-sphere position are calculated, and the normal vector of the sub-sphere vertex is determined accordingly. In the subsequent process, the normal vector is normalized by default before use; given the sub-sphere curvature radius r and its aperture radius h i , we can calculate the vector height ΔS of each sub-sphere vertex away from the base i and the offset length d of the center of each sub-sphere away from the base along the normal vector i ; By the above offset length d i and the normal vector f described in step 1 i Calculate the coordinates of the center of the sub-sphere (x ci ,y ci ,z ci ), and then find the sub-sphere β i The expression z i ; Finally, by comparing the local curvature and sagitta of the base surface and the sub-sphere at any sampling point, the sagitta z(x, y) of the spliced ​​surface γ at the sampling point is determined, thereby determining the surface shape of the spliced ​​surface γ; and

[0145] The multi-point defocus eyeglass lens generating unit 50 is configured to generate the multi-point defocus eyeglass lens by using the splicing curved surface γ as the front surface of the multi-point defocus eyeglass lens and the back surface of the base lens as the back surface of the multi-point defocus eyeglass lens.

[0146] The calculation process of the above-mentioned base lens curvature generation unit 10, sub-spherical surface curvature generation unit 20, sub-spherical surface array arrangement point generation unit 30, splicing surface shape description unit 40 and multi-point defocus eyeglass lens generation unit 50 can be referred to the process description of the above-mentioned multi-point defocus eyeglass lens design method, which will not be repeated here.

[0147] It is to be understood that the structure illustrated in the embodiment of the present invention does not constitute a specific limitation on a multi-point defocus eyeglass lens design device. In other embodiments of the present invention, a multi-point defocus eyeglass lens design device may include more or fewer components than shown in the figure, or combine some components, or split some components, or arrange the components differently. The components shown in the figure may be implemented in hardware, software, or a combination of software and hardware.

[0148] The information interaction, execution process and other contents between the modules in the above-mentioned device are based on the same concept as the embodiment of the method of the present invention. For the specific contents, please refer to the description in the embodiment of the method of the present invention, and no further description is given here.

[0149] An embodiment of the present invention further provides an electronic device, including a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, a multi-point defocus eyeglass lens design method in any embodiment of the present invention is implemented.

[0150] An embodiment of the present invention further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the processor executes a multi-point defocus eyeglass lens design method in any embodiment of the present invention.

[0151] Specifically, a device or apparatus equipped with a storage medium can be provided, on which software program code that implements the functions of any of the above-mentioned embodiments is stored, and the computer (or CPU or MPU) of the device or apparatus can read and execute the program code stored in the storage medium.

[0152] In this case, the program code itself read from the storage medium can realize the function of any one of the above-mentioned embodiments, and thus the program code and the storage medium storing the program code constitute a part of the present invention.

[0153] The storage medium embodiments for providing the program code include a floppy disk, a hard disk, a magneto-optical disk, an optical disk (such as CD-ROM, CD-R, CD-RW, DVD-ROM, DVD-RAM, DVD-RW, DVD+RW), a magnetic tape, a non-volatile memory card, and a ROM. Alternatively, the program code can be downloaded from a server computer by a communication network.

[0154] In addition, it should be clear that the functions of any of the above embodiments can be implemented not only by executing the program code read by the computer, but also by enabling an operating device operating on the computer to complete part or all of the actual operations based on the instructions of the program code.

[0155] In addition, it can be understood that the program code read from the storage medium is written to a memory provided in an expansion board inserted into the computer or to a memory provided in an expansion module connected to the computer, and then based on the instructions of the program code, a CPU installed on the expansion board or expansion module is enabled to perform part or all of the actual operations, thereby realizing the functions of any of the above-mentioned embodiments.

[0156] It should be noted that, in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "comprise a ..." do not exclude the presence of other identical factors in the process, method, article or device including the elements.

[0157] A person of ordinary skill in the art can understand that all or part of the steps of implementing the above method embodiments can be completed by hardware related to program instructions, and the aforementioned program can be stored in a computer-readable storage medium. When the program is executed, it executes the steps of the above method embodiments; and the aforementioned storage medium includes: ROM, RAM, magnetic disk or optical disk, etc., various media that can store program codes.

[0158] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for designing a multi-point defocus eyeglass lens, characterized in that The method comprises the following steps: Step 1: The spliced ​​surface γ can be divided into the base surface α and multiple sub-spheres β i , i is a positive integer, and the base surface α is generated according to the curvature and the quadratic coefficient, and is brought into each sub-sphere β i The position p i The coordinates in the XY plane (x i ,y i ), calculate the position p of each sub-sphere i The vector height and first-order derivative of the base surface at the position p of the sub-sphere are determined from this i The normal vector f of the base surface at i , normal vector f i Use normalized vectors; Step 2: Given the sub-sphere curvature radius r and its aperture radius h i , we can calculate the vector height Δs of each sub-sphere vertex away from the base surface i and the offset length d of the center of each sub-sphere away from the base surface along the normal vector i ; By the above offset length d i and the normal vector f described in step 1 i Calculate the subsphere β i The coordinates of the center of the sphere, and then find the sub-sphere β i Expression of Step 3: For any sampling point, calculate the local curvature of the base surface α at the sampling point, and compare the base surface α with the sub-sphere β i The local curvature and sagitta at the sampling point determine the sagitta z(x,y) of the spliced ​​surface γ at the sampling point.

2. The design method according to claim 1, characterized in that: In step 1, the base surface α uses a quadratic surface, and its specific expression is: Among them, c base represents the curvature, k base represents the quadratic coefficient, (x, y) is the coordinate on the base surface, z base (x,y) represents the base surface α; The first derivative of the basis surface α and The expression is: in, is the simplified expression of the derivative of the basis surface α with respect to x, is the simplified expression of the derivative of the basis surface α with respect to y; Subsphere β i The normal vector of the vertex is 3. The design method according to claim 2, characterized in that: In step 2, the offset length d i The expression is: Subsphere β i The coordinates of the center of the sphere (x ci ,y ci ,z ci ) can be expressed as: (x ci ,y ci ,z ci )=(x i ,y i ,z i )-d i f i , Among them, (x i ,y i ,z i ) is the i-th subsphere β i The position p i The coordinates of The sub-sphere β i It can be expressed as:

4. The design method according to claim 3, characterized in that: In step 3, the base surface α is a rotationally symmetric surface, and its local curvature c at point (x, y) is base (ρ) is expressed in radial coordinate ρ as: Subsphere β i The curvature c is expressed as:

5. The design method according to claim 4, characterized in that: In step 3, for any sampling point, the subsphere β i The local curvature c i Equal to the subsphere β i The curvature c of the subsphere β i When the local curvature of the base surface α is of different sign, the splicing surface γ can be expressed as: When the subsphere β i When the local curvature of the subsphere β is of the same sign as the local curvature of the base surface α, i The local curvature c i Greater than the local curvature c of the base surface α base , the splicing surface γ can be expressed as: When the subsphere β i When the local curvature of the subsphere β is of the same sign as the local curvature of the base surface α, i The local curvature c i Less than the local curvature c of the base surface α base , the splicing surface γ can be expressed as:

6. The design method according to claim 1, characterized in that: The step 3 comprises the following sub-steps: calculating the local curvature of any sampling point of the base surface α, and calculating the local curvature of the base surface α and the adjacent sub-spherical surfaces β at the sampling point. i The local curvature and vector height of the sampling point are used to determine whether the sampling point belongs to the base surface α. If so, the vector height of the base surface α is used as the vector height at the sampling point. Otherwise, the vector height of the base surface α is combined with the adjacent multiple sub-spheres β. i The local curvature and sagitta of are used to obtain the sagitta of the spliced ​​surface γ at the sampling point.

7. The design method according to claim 1, characterized in that: The design process of designing multi-point defocus eyeglass lenses using the curved substrate lens array splicing method includes the following steps: Step 101: The curvatures of the front and back surfaces of the base lens are adjusted according to the required corrective diopter D. c design; Step 102: The sub-spherical surface takes the front surface S1 of the base lens as the base curved surface, and the curvature of the sub-spherical surface is determined according to the required myopia defocus diopter D. sub design; Step 103: In a curved surface coordinate system with the base curved surface as the coordinate axis, generate the arrangement points q of the sub-spherical array on the base curved surface according to the required arrangement method. i , map the coordinates of the arrangement points from the curved coordinate system to the plane perpendicular to the Z axis in the rectangular coordinate system, and obtain the sub-sphere β i The position p i The coordinates in the XY plane (x i ,y i ); Step 104, combining the curved surface base lens array stitching method to obtain the stitching curved surface γ, and using the stitching curved surface γ as the front surface of the multi-point defocus eyeglass lens, and using the back surface of the base lens as the back surface of the multi-point defocus eyeglass lens, to generate the multi-point defocus eyeglass lens.

8. The design method according to claim 7, characterized in that: In step 101, the glasses are regarded as thin lenses, and the corrected diopter D c The expression is: Wherein, f represents the focal length of the base lens, n2 represents the refractive index of the base lens material, n1 represents the refractive index of air, R1 represents the curvature radius of the front surface S1 of the base lens, and R2 represents the curvature radius of the back surface S2 of the base lens.

9. The design method according to claim 8, characterized in that: In step 102, the myopic defocus diopter D sub The expression is: Where r represents the radius of curvature of the sub-sphere.

10. The design method according to claim 9, characterized in that: In step 103, the process of mapping the arrangement point coordinates from the curved surface coordinate system to the coordinates in the XY plane of the rectangular coordinate system uses the following mapping expression: Among them, (x i_surf ,y i_surf ) represents the front row of points q i The coordinates in the surface coordinate system, (x i ,y i ) represents the subsphere β after mapping i The position p i Coordinates on the XY plane in rectangular coordinates.

11. A design device for multi-point defocus eyeglass lenses, used to implement the design method according to any one of claims 7 to 10, characterized in that: include: The base lens curvature generating unit is configured to correct the diopter D according to the required diopter D c Designing the curvature of the front and back surfaces of the base lens; The sub-spherical curvature generating unit is configured to generate a sub-spherical curvature according to the required myopia defocus diopter D sub The curvature of the sub-spherical surface is designed, and the sub-spherical surface takes the front surface S1 of the base lens as the base curved surface; The sub-spherical surface position generating unit is configured to generate the arrangement points q of the sub-spherical surface array on the base curved surface in the curved surface coordinate system with the base curved surface as the coordinate axis according to the required arrangement mode. i , and map the coordinates of the arrangement points from the curved coordinate system to the XY plane of the rectangular coordinate system to obtain the sub-sphere β i The position p i The coordinates in the XY plane (x i ,y i ); A splicing curved surface profile description unit, configured to generate the splicing curved surface γ according to the curved surface base lens array splicing method; and The multi-point defocus eyeglass lens generating unit is configured to use the splicing curved surface γ as the front surface of the multi-point defocus eyeglass lens and use the back surface of the base lens as the back surface of the multi-point defocus eyeglass lens to generate the multi-point defocus eyeglass lens.

12. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and the computer program is used to enable a computer to execute the multi-point defocus spectacle lens design method according to any one of claims 1 to 10.

13. An electronic device, comprising at least a processor and a memory, characterized in that: The memory stores a computer program, and when the processor executes the computer program, the multi-point defocus spectacle lens design method according to any one of claims 1 to 10 is implemented.

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