Progressive multifocal spectacle lens and evaluation method

Abstract

The invention discloses a progressive multifocal spectacle lens and an evaluation method. The evaluation method comprises the following steps: carrying out region division on the surface of a spectacle lens to form an interference evaluation region; acquiring an astigmatism interference index according to the interference evaluation area; obtaining a distortion interference index according to the interference evaluation area; and based on the astigmatism interference index and the distortion interference index, obtaining an evaluation interference index, and combining the theoretical interference performance value interval of the spectacle lens to evaluate the performance of the spectacle lens. According to the invention, the wearing comfort of different lens designs can be quantified, and the method is suitable for the initial stage of progressive multi-focus spectacle lens design and the optical performance evaluation of lens samples; a novel measuring method for the optical performance of the progressive lens surface type can be provided for lens designers and wearers.

Description

Technical Field

[0001] The present application belongs to the field of ophthalmic optics technology, and specifically relates to a progressive multifocal spectacle lens and an evaluation method. Background Art

[0002] The effective visual area of ​​progressive multifocal lenses is usually divided into three areas, including: distance zone, progressive channel and near zone. Although the wearing comfort and adaptation time of progressive lenses are inseparable from the physiological characteristics of the human eye, they still depend to a large extent on the optical performance of the lens itself. Relatively speaking, the lower the interference of the lens during design, the higher the comfort of the wearer during wearing, and the adaptation time will be significantly reduced. The existing evaluation of the optical performance of progressive lenses mainly considers the following aspects: (1) the size of the distance zone and the near zone; (2) the type and size of aberrations; (3) the length of the progressive channel and the visually available width. Under this evaluation method, when a progressive lens has the largest possible effective visual area, a short and wide progressive channel, and a gently changing astigmatism, it can be regarded as an ideal progressive lens. In fact, lenses of different designs have different characteristics, and there is also a certain compromise and balance between the effective visual area and the blind spot. Therefore, although the above method can provide general performance indicators of progressive lenses, it lacks effectiveness in evaluating the interference performance of lenses of different designs. Summary of the invention

[0003] Purpose of the invention: The embodiment of the present application provides a progressive multifocal lens and an evaluation method thereof, aiming to perform a more detailed and universal mid-range interference analysis for progressive multifocal lenses of different designs. The method provides a more complete solution in interference evaluation, making the performance evaluation of the lens more comprehensive and accurate.

[0004] Technical solution: A method for evaluating a progressive multifocal spectacle lens of the present application comprises the following steps:

[0005] Dividing the surface of the eyeglass lens into regions to form interference evaluation regions;

[0006] According to the interference evaluation area, obtaining an astigmatism interference index;

[0007] Obtaining a distortion interference index according to the interference evaluation area;

[0008] Based on the astigmatism interference index and the distortion interference index, an evaluation interference index is obtained, and combined with the theoretical interference performance value range of the spectacle lens, the performance of the spectacle lens is evaluated.

[0009] In some embodiments, the step of dividing the surface of the eyeglass lens into regions to form interference evaluation regions further includes:

[0010] A rectangular coordinate system is constructed with the geometric center of the eyeglass lens as the origin O, the vertical direction as the x-axis, and the horizontal direction as the y-axis;

[0011] Determine a distance reference point A and a near reference point C of the eyeglass lens respectively on both sides of the origin O on the x-axis;

[0012] Determine a position B of the fitting cross of the spectacle lens on the x-axis, wherein the position B is located between the distance reference point A and the origin O;

[0013] The surface of the eyeglass lens corresponding to the position A to the near reference point C is defined as the interference evaluation area.

[0014] In some embodiments, the eyeglass lens has a geometric center and an edge, and the step of obtaining the astigmatism interference index according to the interference evaluation area further includes:

[0015] Dividing the interference evaluation area into a channel interference area, a reference interference area, and a blind interference area which are arranged in sequence from the optical center to the edge;

[0016] Based on the channel interference area, the reference interference area and the blind area interference area, respectively obtain a channel interference index p1, a reference interference index p2 and a blind area interference index p3;

[0017] Determine a weight coefficient w1 corresponding to the channel interference index p1, a weight coefficient w2 corresponding to the reference interference index p2, and a weight coefficient w3 corresponding to the blind spot interference index p3;

[0018] The weight coefficient is combined with the corresponding interference index to obtain the astigmatism interference index, and the calculation expression of the astigmatism interference index is:

[0019]

[0020] Among them, P a N represents the astigmatism interference index; ind =3; p i represents any one of the channel interference index, the reference interference index, and the blind area interference index; i Represents the weight coefficients corresponding to the channel interference index, the reference interference index, and the blind spot interference index.

[0021] In some embodiments, the calculation expression of the channel interference index p1 is:

[0022]

[0023] Among them, ω1 represents the average width of the visual transition position; ω| minrepresents the minimum theoretical width; ω| max Indicates the theoretical maximum width.

[0024] In some embodiments,

[0025] ω| min The expression is:

[0026] ω| max The expression is:

[0027] Among them, C th represents the astigmatism threshold; ADD represents the additional optical power from the distance reference point A to the near reference point C; s represents the distance between the position B and the origin O; h represents the distance between the distance reference point A and the near reference point C.

[0028] In some embodiments, the calculation expression of the reference interference index p2 is:

[0029]

[0030] Among them, C ref Indicates the reference blind zone astigmatism; C ref | min Indicates the minimum value of astigmatism in the theoretical reference blind zone; C ref | max Indicates the maximum value of theoretical reference blind zone astigmatism.

[0031] In some embodiments,

[0032] C ref | min The expression is:

[0033] C ref | max The expression is:

[0034] Where Δ represents the distance between the reference position and position B in the direction of the x-axis, and ADD represents the additional optical power from the distance reference point A to the near reference point C; s represents the distance between position B and the origin O; h represents the distance between the distance reference point A and the near reference point C; l represents the distance between the distance reference point A and the origin O.

[0035] In some embodiments, the blind spot interference index p3 is calculated as:

[0036]

[0037] Where k1 represents the distance coefficient of the position of the maximum astigmatism in the blind area; Cnas Indicates the maximum astigmatism in the blind zone; C nas | min Indicates the minimum value of the maximum astigmatism in the theoretical blind zone; C nas | max Indicates the maximum value of the maximum astigmatism in the theoretical blind zone.

[0038] In some embodiments,

[0039] The expression of k1 is:

[0040] C nas | min The expression is:

[0041] C nas | max The expression is: C nas | max =2ADD;

[0042] Among them, ADD represents the additional optical focal length from the distance reference point A to the near reference point C; s represents the distance between the position B and the origin O; h represents the distance between the distance reference point A and the near reference point C; l represents the distance between the distance reference point A and the origin O; x1 and y1 represent the coordinates of the position of the maximum astigmatism in the blind spot interference area.

[0043] In some embodiments, the step of determining the weight coefficient w1 corresponding to the channel interference index p1, the weight coefficient w2 corresponding to the reference interference index p2, and the weight coefficient w3 corresponding to the blind spot interference index p3 further includes:

[0044] Determine the initial weights of the channel interference index p1, the reference interference index p2, and the blind area interference index p3 by a systematic evaluation method;

[0045] The initial weights are optimized by an adaptive genetic algorithm to obtain the corresponding weight coefficients w1, w2 and w3 after optimization.

[0046] In some embodiments, the step of obtaining the distortion interference index according to the interference evaluation area further includes:

[0047] Dividing the interference evaluation area into m circular areas, adjacent circular areas are tangent to each other;

[0048] Based on the magnification of the m circular areas, the distortion interference index is obtained, and the calculation expression of the distortion interference index is:

[0049]

[0050] Where m represents the number of divided circular areas, and the range of m is a positive integer between 6 and 27; β i is the magnification of the i-th circular area, and is the average optical power of the i-th circular area.

[0051] In some embodiments, the calculation expression for evaluating the interference index is:

[0052]

[0053] Wherein, P represents the evaluation interference index.

[0054] In some embodiments, the theoretical interference performance value interval ranges from 0 to 100.

[0055] In some embodiments, the present application also provides a spectacle lens evaluated using the evaluation method.

[0056] Beneficial effects: Compared with the prior art, the evaluation method of the present application can quantify the wearing comfort of different lens designs, and is suitable for the initial design of progressive multifocal lenses and the optical performance evaluation of lens samples; by calculating and obtaining the evaluation interference index, it can provide lens designers and wearers with a new method for measuring the optical performance of progressive lens surfaces, which is compatible with lenses of different designs and gives their interference performance, which can not only help designers measure their interference performance in the initial stage of lens design, but also provide wearers with an effective evaluation method when selecting lenses; the method provided in the present application provides a more complete solution in terms of interference evaluation, making the performance evaluation of lenses more comprehensive and accurate. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0058] Figure 1 This is a schematic diagram of the functional areas of a conventional progressive multifocal spectacle lens;

[0059] Figure 2 This is a schematic xOy plane diagram of a progressive addition lens provided in an embodiment of the present application;

[0060] Figure 3 A schematic diagram of the division of the surface area of ​​a progressive multifocal spectacle lens provided in an embodiment of the present application;

[0061] Figure 4A schematic diagram of parameters in the astigmatism interference evaluation method provided in this application;

[0062] Figure 5 This is a flow chart for calculating the weight coefficient in the evaluation method of this application;

[0063] Figure 6 A schematic diagram of obtaining the distortion interference index provided by this application;

[0064] Figure 7 A comparison diagram of the adaptive genetic algorithm and the genetic algorithm evolution process in Example 1;

[0065] Figure 8 The astigmatism contour distribution diagram of the progressive multifocal spectacle lens in Example 2;

[0066] Fig. 9 This is the astigmatism contour distribution diagram of the progressive multifocal spectacle lens in Example 3. DETAILED DESCRIPTION

[0067] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0068] In the description of the present application, it should be understood that the terms "upper", "lower", "top", "bottom", "inside", "outside", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In the description of the present application, "plurality" means two or more than two, and at least one means one, two or more than two, unless otherwise clearly and specifically defined.

[0069] See also Figure 1, the effective visual area of ​​conventional progressive multifocal spectacle lenses is usually divided into: far zone ①, progressive channel ②, near zone ③, and blind zones ④ and ⑤ on both sides of the lens periphery. The far zone can meet the needs of long-distance vision, such as driving, outdoor hiking and other activities; the near zone can meet the needs of close-range vision, such as reading, writing, etc.; the progressive channel is between the far zone and the near zone, and is used for medium-distance activities between long distance and close distance. The curvature in this area changes continuously, which can better meet the wearer's needs for far and near vision at the same time; the blind zone is the area that affects the optical performance of the progressive lens, and there is a large interference in this area. Taking the right eye as an example, the nasal blind zone is blind zone ④, the temporal blind zone is blind zone ⑤, and the left eye is the opposite. Although the wearing comfort and adaptation time of progressive lenses are inseparable from the physiological characteristics of the human eye, they still depend to a large extent on the optical performance of the lens itself. Relatively speaking, the lower the interference of the lens in design, the higher the comfort of the wearer during wearing, and the adaptation time will be significantly reduced. The existing evaluation of the optical performance of progressive lenses mainly considers the following aspects: (1) the size of the distance and near vision zones; (2) the type and size of aberrations; (3) the length of the progressive channel and the visually available width. Under this evaluation method, a progressive lens can be considered an ideal progressive lens when it has the largest possible effective visual area, a short and wide progressive channel, and a gently changing astigmatism. In fact, lenses of different designs have different characteristics, and there is a certain compromise and balance between the effective visual area and the blind spot. Therefore, although the above method can provide general performance indicators of progressive lenses, it lacks effectiveness in evaluating the interference performance of lenses of different designs.

[0070] Based on this, the present application solves the above-mentioned technical problems by providing an evaluation method for progressive multifocal lenses.

[0071] The present invention provides a method for evaluating a progressive multifocal spectacle lens, comprising the following steps:

[0072] Dividing the surface of the eyeglass lens into regions to form interference evaluation regions;

[0073] According to the interference evaluation area, the astigmatism interference index is obtained;

[0074] According to the interference evaluation area, the distortion interference index is obtained;

[0075] Based on the astigmatism interference index and the distortion interference index, an evaluation interference index is obtained, and combined with the theoretical interference performance value range of the spectacle lens, the performance of the spectacle lens is evaluated.

[0076] It can be understood that in the evaluation method of the present application, by calculating and obtaining the evaluation interference index, a new method for measuring the optical performance of the surface type of progressive lenses can be provided to lens designers and wearers. Among them, the evaluation interference index is jointly determined by the astigmatism interference index and the distortion interference index. The astigmatism interference index is mainly used to evaluate the visual clarity of the lens, which is specifically manifested as a blurred and unclear state of vision; the distortion interference index is used to evaluate the imaging mode of the lens, which is specifically manifested as a deformed and distorted state of vision. It should be noted that the low-order aberration that has the greatest impact on visual acuity among aberrations is astigmatism, and due to the design characteristics of the progressive lens itself, the distortion interference at mid-range will also cause the wearer to have visual deformation, or produce a sense of shaking when the line of sight changes; therefore, the mid-range interference evaluation of progressive lenses can be divided into the mid-range interference evaluation of astigmatism and distortion. By designing the astigmatism interference index and the distortion interference index, it is possible to be compatible with lenses of different designs and give their interference performance, making the performance evaluation of the lens more comprehensive and accurate.

[0077] In some embodiments, the theoretical interference performance value interval specifically describes whether the design of the progressive multifocal lens can effectively reduce or eliminate the visual interference caused by astigmatism and distortion, and the range is set to 0 to 100. In fact, for the interference degree of progressive lenses with different additional diopter (ADD), generally speaking, the lower the ADD, the lower the interference. Therefore, the interference performance of lenses with different ADDs has their own upper and lower limits in theory. Take the astigmatism interference index as an example: for progressive lenses with an ADD of 2.0D, the upper limit of the astigmatism interference index is 90, and the lower limit is 10. The lower the interference index, the better the performance. The distortion interference index exceeding 100 is not included in the evaluation range, and the lower limit is 0. Therefore, it can be judged that the smaller the value, the smaller the distortion interference; the larger the value, the greater the effect of the distortion interference.

[0078] In some embodiments, the step of dividing the surface of the eyeglass lens into regions to form interference evaluation regions further includes:

[0079] A rectangular coordinate system is constructed with the geometric center of the eyeglass lens as the origin O, the vertical direction as the x-axis, and the horizontal direction as the y-axis;

[0080] Determine the far reference point A and the near reference point C of the eyeglass lens on both sides of the origin O on the x-axis;

[0081] Determine the position B of the fitting cross of the spectacle lens on the x-axis, and the position B is located between the distance reference point A and the origin O;

[0082] The surface of the eyeglass lens corresponding to the position A to the near reference point C is defined as the interference evaluation area.

[0083] For further information, see Figure 2, O is the coordinate origin and also the location of the geometric center of the lens, A is the reference point for distance use, l is the distance from point A to point O, C is the reference point for near use, the distance between point A and point C is h and the focal length of the lens increases smoothly from point A to point C, the additional focal length is ADD, B is the location of the lens assembly cross, BO=s, the positive direction of the y-axis is horizontal to the right, the positive direction of the x-axis is vertically upward, and the coordinate axis unit is mm. Therefore, the interference evaluation area can also be understood as the middle area of ​​the progressive multifocal lens, that is, the range covered from the distance l above the geometric center to the distance hl below it. It can be understood that by defining the interference evaluation area on the lens, a more detailed and universal mid-distance interference analysis can be performed for progressive multifocal lenses of different designs.

[0084] In some embodiments, the eyeglass lens has a geometric center and an edge, and the step of obtaining the astigmatism interference index according to the interference evaluation area further includes:

[0085] The interference evaluation area is divided into a channel interference area, a reference interference area and a blind interference area which are arranged in sequence from the optical center to the edge;

[0086] Based on the channel interference area, the reference interference area and the blind area interference area, a channel interference index p1, a reference interference index p2 and a blind area interference index p3 are obtained respectively;

[0087] Determine a weight coefficient w1 corresponding to a channel interference index p1, a weight coefficient w2 corresponding to a reference interference index p2, and a weight coefficient w3 corresponding to a blind spot interference index p3;

[0088] The weight coefficient is combined with the corresponding interference index to obtain the astigmatism interference index, and the calculation expression of the astigmatism interference index is:

[0089]

[0090] Among them, P a N represents the astigmatism interference index; ind =3; p i represents any one of the channel interference index, reference interference index, and blind zone interference index; w i Indicates the weight coefficients corresponding to the channel interference index, reference interference index, and blind zone interference index.

[0091] It is understandable that further see Figure 3 and Figure 4 , the channel interference area, reference interference area and blind interference area are Figure 3 The area defined by the corresponding lens surface is different from the surface division of conventional progressive multifocal lenses. Figure 3The astigmatism interference index is determined by the mid-range channel interference index located in the channel interference area, the mid-range reference interference index located in the reference interference area, and the mid-range blind zone interference index located in the blind zone interference area.

[0092] In some embodiments, the calculation expression of the channel interference index p1 is:

[0093]

[0094] Among them, ω1 represents the average width at the visual transition position; ω| min represents the minimum theoretical width; ω| max Indicates the theoretical maximum width.

[0095] It is understandable that Figure 3 It can be seen that the channel interference index further includes the 0.5D channel interference index and the 1.0D channel interference index, and both can be obtained through the calculation expression of the channel interference index p1, that is, the channel interference index p1 is obtained by adding the calculated 0.5D channel interference index and 1.0D channel interference index. Figure 2 Taking the division as an example, the average width at the visual transition position specifically includes The average width of 0.5D or 1.0D at .

[0096] According to Minkwitz's theorem, the relationship between the lens contour and the channel width is: C(y)≈2|P'(x)|y, where P'(x) is the rate of change of the optical power along the positive direction of the x-axis. The above formula can be used to determine a certain threshold value C of astigmatism. th The distance to the meridian zone, the equation becomes: In the formula, y th is the distance from the threshold of astigmatism to the meridian zone. For a given astigmatism threshold, the channel width ω(x) is y th Twice, the specific expression is:

[0097] Based on the above relationship, we get ω| min The expression is: ω| max The expression is: Among them, C th represents the astigmatism threshold; ADD represents the additional optical power from the distance reference point A to the near reference point C; s represents the distance between the position B and the origin O; h represents the distance between the distance reference point A and the near reference point C.

[0098] Furthermore,ω| min The range is 0.25~5.5.

[0099] Furthermore,ω|max The range is 23 to 40.

[0100] The blind zone interference index further includes the maximum astigmatism of the nasal blind zone and the maximum astigmatism of the temporal blind zone.

[0101] In some embodiments, the calculation expression of the reference interference index p2 is:

[0102]

[0103] Among them, C ref Indicates the reference blind zone astigmatism; C ref | min Indicates the minimum value of astigmatism in the theoretical reference blind zone; C ref | max Indicates the maximum value of theoretical reference blind zone astigmatism.

[0104] Understandably, see Figure 4 , the reference position is set to the position of point P, θ = 45° (when the human eye rotates horizontally by several degrees, the direction of astigmatism and distortion changes strongly from the progressive channel to the tilt of about 45°), the reference position is set to the position with a distance Δ below the assembly cross B, that is, Δ represents the distance between the reference position and position B in the direction of the x-axis, and C ref Specifically defined as the maximum astigmatism within a radius of 1 to 2 mm with the reference position as the center of the circle, it is defined as the blind zone reference astigmatism. For a symmetrical design, the nasal temporal side is at a distance of Δ from the y-axis on both sides of the y-axis, that is, Figure 4 The P1 and P2 points are symmetrical; for asymmetrical designs, the inner bias value d is taken into account, which is Δ-d on the temporal side.

[0105] According to Minkwitz's theorem, the change in astigmatism at a distance from the channel is roughly equal to twice the change in the additional diopter (ADD) at an equal distance along the channel. At this time, the maximum astigmatism in the theoretical reference blind zone is C ref | max , and C ref | max The expression is: The effective mid-range field of view is set to start from the assembly center B, and the minimum astigmatism of the theoretical benchmark blind area is C. ref | min , and C ref | min The expression is: Where Δ represents the distance between the reference position and position B in the direction of the x-axis, and ADD represents the additional optical power from the distance reference point A to the near reference point C; s represents the distance between position B and the origin O; h represents the distance between the distance reference point A and the near reference point C; l represents the distance between the distance reference point A and the origin O

[0106] Furthermore, C ref | min The range is 0.15~3.

[0107] Furthermore, C ref | max The range is 0.2~7.3.

[0108] In some embodiments, the blind spot interference index p3 is calculated as:

[0109]

[0110] Where k1 represents the distance coefficient of the position of the maximum astigmatism in the blind area; C nas Indicates the maximum astigmatism in the blind zone; C nas | min Indicates the minimum value of the maximum astigmatism in the theoretical blind zone; C nas | max Indicates the maximum value of the maximum astigmatism in the theoretical blind zone.

[0111] It can be understood that the blind spot interference index p3 includes the maximum astigmatism of the nasal blind spot and the maximum astigmatism of the temporal blind spot, and both can be obtained through the calculation expression of the blind spot interference index p3, that is, the blind spot interference index p3 is obtained by adding the maximum astigmatism of the nasal blind spot and the maximum astigmatism of the temporal blind spot. Although the blind spot interference has a certain relationship with the maximum astigmatism of the blind spot, the location of the maximum astigmatism of the blind spot of different designs is different. For this reason, the distance coefficient k1 is set to standardize the astigmatism of different designs. Assuming that the location of the maximum astigmatism of the nasal blind spot is (x1, y1), the expression of k1 is:

[0112] Minkwitz theorem shows that the change in astigmatism at a distance from the channel is roughly equal to twice the change in the additional optical power (ADD) at the same distance along the channel. At this time, the maximum astigmatism in the theoretical blind zone is C nas | max , C nas | max The expression is: C nas | max =2ADD; specifically, C nas | max The range is 1.5 to 8; the minimum value of astigmatism in the theoretical blind zone is C nas | min , C nas | min The expression is: Specifically, C. nas | min The range is 0.15~3.

[0113] Among them, ADD represents the additional optical focal length from the distance reference point A to the near reference point C; s represents the distance between the position B and the origin O; h represents the distance between the distance reference point A and the near reference point C; l represents the distance between the distance reference point A and the origin O; x1 and y1 represent the coordinates of the position of the maximum astigmatism in the blind spot interference area.

[0114] In some embodiments, the step of determining a weight coefficient w1 corresponding to the channel interference index p1, a weight coefficient w2 corresponding to the reference interference index p2, and a weight coefficient w3 corresponding to the blind spot interference index p3 further includes:

[0115] Determine the initial weights of the channel interference index p1, the reference interference index p2, and the blind zone interference index p3 through a systematic evaluation method;

[0116] The initial weights are optimized by an adaptive genetic algorithm to obtain the corresponding weight coefficients w1, w2 and w3 after optimization.

[0117] It is understandable that providing a relatively accurate initial weight for each influencing indicator through systematic evaluation methods such as hierarchical analysis method and fuzzy comprehensive evaluation model can help reduce the error caused by complete reliance on other algorithms and improve the accuracy of the final result. The initial weights obtained by preprocessing through the above method can be used as input, so that other algorithms can start from a more reasonable starting point when optimizing, which can not only speed up the convergence speed and improve efficiency, but also reduce the risk of falling into the local optimal solution and enhance the robustness of the final evaluation results. In addition, the weight coefficients obtained by the above method are somewhat subjective, and the adaptive genetic algorithm can be applied to the optimization of multiple weight coefficients. Each weight can be encoded and the combination of multiple weights can be represented in the form of chromosomes. Compared with the traditional genetic algorithm, this method is less likely to fall into the local optimal solution in the process of continuous iteration and has higher optimization efficiency. Therefore, the adaptive genetic algorithm is used to automatically optimize with the initial weight as the starting point to improve the accuracy of the results and the convergence speed.

[0118] See Figure 5 , including the following steps:

[0119] (1) Encode and generate the initial population

[0120] The chromosome length is set to L (5≤L≤10), the population size is set to V (100≤V≤800), the initial weights obtained by systematic evaluation methods such as hierarchical analysis method and fuzzy comprehensive evaluation model are combined with random functions, and binary encoding is used to generate binary strings as the initial chromosomes and generate the initial population.

[0121] (2) Fitness calculation

[0122] The objective function is used as a measurement method to measure the completion of an individual in the problem domain. In a minimization problem, the most suitable individual corresponds to the minimum objective function value. In this embodiment, the required objective function is set as: in, and Respectively represent the theoretical widths of 0.5D channel and 1.0D channel, They represent the baseline blind zone astigmatism, the maximum astigmatism of the nasal blind zone, and the maximum astigmatism of the temporal blind zone, respectively.

[0123] The fitness function is usually used to convert the objective function value into a relative fitness value. When the objective function is a minimization problem, the fitness function corresponding to the objective function can be expressed as: F = a·f+b; where a is the conversion coefficient, and its sign is determined by the objective function. In this method, a < 0, b is the offset value, and b > 0 is used to ensure that the final fitness value is non-negative, where the values ​​of a and b are calculated by existing public genetic algorithm technology.

[0124] (3) Preservation and selection

[0125] The operation of protecting the best individuals and accelerating the elimination of the worst individuals is adopted. The first N individuals in the population fitness are selected for protection, and the last N individuals are eliminated. The population after removing the N individuals is subjected to selection processing, wherein the selection operation operator in the selection processing is roulette selection. Among them, N is 10% to 15% of the initial population.

[0126] (4) Self-mutation and self-crossover process

[0127] The self-crossover probability and self-mutation probability in the adaptive genetic algorithm can change with the individual fitness, which has better globality than the fixed crossover and mutation probabilities. If the fitness function of a generation is greater than the average level of the fitness function, it means that the performance of the individual is better, and the crossover and mutation probabilities should be reduced to retain the excellent genes as much as possible. Otherwise, crossover and mutation should be performed on them.

[0128] The expression of self-mutation probability p c (0.5≤p c ≤1.0) is:

[0129]

[0130] Among them, p c | max and p c | min are the maximum and minimum values ​​of the probability of self-mutation, F max and are the maximum and average values ​​of fitness, respectively.

[0131] The self-crossover probability expression pm (0.005≤p m ≤0.5) is:

[0132]

[0133] Among them, p m | max and p m | min are the maximum and minimum values ​​of the self-crossover probability, F max and are the maximum and average values ​​of fitness, respectively.

[0134] (5) Output the optimal solution

[0135] During the optimization iteration process, if the output condition is met, the final weight coefficient is output. The output condition is that the objective function value is less than the set threshold or the maximum number of iterations is reached. Otherwise, the above steps (2) to (4) are repeated until the output condition is met.

[0136] In some embodiments, the step of obtaining the distortion interference index according to the interference evaluation area further includes:

[0137] The interference evaluation area is divided into m circular areas, and adjacent circular areas are tangent to each other;

[0138] Based on the magnification of the m circular areas, the distortion interference index is obtained. The calculation expression of the distortion interference index is:

[0139]

[0140] Where m represents the number of divided circular areas; β i is the magnification of the i-th circular area, and is the average optical power of the i-th circular area.

[0141] See also Figure 6 , used to calculate distortion interference, the lens surface is divided as follows Figure 6 The optical power value in the circular area shown is calculated and the degree of distortion is measured by the magnification. The larger the index obtained, the more serious the distortion is, and the stronger the wearer's sense of deformation and shaking when viewing objects. Figure 6 As an example, the lens surface from the assembly cross B to the near reference point C contains m circular areas for evaluating distortion interference. The specific calculation expression of m is: r is the radius of the circular area, which is the pupil radius and ranges from 1 to 2 mm. In fact, m ranges from 6 to 27.

[0142] The center point of the circular area is O i, i=1,2,...,m are arranged tangentially along the vertical direction of the x-axis in the symmetrical design, point O1 is located directly below the lens assembly cross B, circle O i There are circles of the same size tangent to the left and right sides. Traditional single-vision lenses can produce distortion interference that is easier to adapt to while correcting refractive errors because the focal power does not change. Progressive multifocal lenses have the characteristic of gradually changing focal power from top to bottom, which usually produces larger distortion and affects the visual experience of the wearer. In this embodiment, the distortion interference is quantified, and a calculation method for the distortion interference index is further proposed. The specific expression is:

[0143] In some embodiments, the calculation expression for evaluating the interference index is:

[0144] Wherein, P represents the evaluation interference index.

[0145] In some embodiments, a spectacle lens is provided, which is obtained by the evaluation method provided in this embodiment. The material of the spectacle lens includes a polymer material or an inorganic non-metallic material. Among them, the polymer material includes a thermoplastic resin or a thermosetting resin, and the inorganic non-metallic material includes glass, etc. Thermoplastic resins include polycarbonate or polymethyl methacrylate; thermosetting resins include any one of acrylic resins, episulfide resins, thiourethane resins, allyl resins, and polyurethanes.

[0146] In some embodiments, a coating film is formed on the surface of at least one side of the eyeglass lens, and the coating film includes a transparent coating film that increases the transmittance of the lens, a hard coating film that increases the durability of the lens, a reflective film that blocks harmful light, an anti-reflection and anti-reflection film that realizes imaging visibility, a polarizing film with a color-changing function, or other color-changing films doped with ultraviolet-sensitive materials, etc. The coating film itself can have different colors, and the visual color under the reflection condition can be green, blue, yellow, purple, etc., or other colors.

[0147] Example 1

[0148] In this embodiment, when determining the astigmatism interference index, the weight coefficients of the influencing factors such as the channel, the reference position, and the blind area astigmatism are preprocessed through systematic evaluation. Taking the analytic hierarchy process as an example, the mid-range interference is taken as the optimization target, and the judgment matrix is ​​constructed with the 0.5D channel interference index, the 1.0D channel interference index, the reference interference index, the nasal blind area interference index, and the temporal blind area interference index as the influencing indicators, and the corresponding weight coefficients are calculated as the initial weights. The final calculation results are: 0.5D channel interference index weight: 32%; 1.0D channel interference index weight: 28%; reference interference index weight: 20%; nasal blind area interference index weight: 10%; temporal blind area interference index weight: 10%.

[0149] Then, the adaptive genetic algorithm was used for further optimization, and the output threshold of the objective function was set to 10. The corresponding parameters are shown in Table 1. At the same time, the genetic algorithm was used for automatic optimization under the same conditions, and the optimization results were obtained: 0.5D channel interference index weight: 31%; 1.0D channel interference index weight: 26%; baseline interference index weight: 21%; nasal blind spot interference index weight: 11%; temporal blind spot interference index weight: 11%.

[0150] Table 1 Adaptive genetic algorithm parameters

[0151] Chromosome length 5 Population size 200 Crossover probability 50％ Mutation probability 5％ Maximum Algebra 100 Elimination probability 10％ Protection probability 10％

[0152] The optimization effect comparison between the method of this embodiment and the genetic algorithm is shown in the attached Figure 7 ,It can be found from the figure that compared with the genetic algorithm that takes the fitness value of 21.03 as the starting point and reaches the optimal fitness in the 41st generation, the adaptive genetic algorithm after preprocessing has a higher fitness at the starting point, with a starting value of 21.06, and reaches the optimal fitness value in the 34th generation. Therefore, the adaptive genetic algorithm of this embodiment can improve the optimization efficiency and accuracy to a certain extent.

[0153] Example 2

[0154] In this example, progressive multifocal lenses with the same additional power of 2.0D are used to evaluate the mid-distance interference of three different designs of progressive multifocal lenses. The distribution of their astigmatism contour lines can be found in Figure 8 Specific parameters and distortion interference are shown in Table 2. In lenses 1 to 3, s is 4mm, hl is 12mm, 10mm and 14mm respectively, l is 10mm, and the internal deviation value is 2mm. According to the parameters of the three lenses, calculations are performed respectively and the final astigmatism mid-distance interference calculation results are obtained.

[0155] Table 2 Parameters of progressive lenses with the same additional focal power

[0156]

[0157] From Table 2 and Figure 8It can be seen that when evaluating lenses with the same ADD value under the previous evaluation standards, the optical performance of lens 1 is significantly better than that of lenses 2 and 3, but the difference cannot be accurately measured by numerical values. After introducing the interference index calculation method, the performance of these three lenses can be more intuitively compared: the channel, reference and blind zone interference indexes of lens 1 are 44.44, 6.04 and 8.16 respectively, and the astigmatism interference index is 58.64; the channel, reference and blind zone interference indexes of lens 2 are 45.2, 12.83 and 10.59 respectively, and the astigmatism interference index is 68.62; the channel, reference and blind zone interference indexes of lens 3 are 48.39, 11.26 and 6.82 respectively, and the astigmatism interference index is 66.47. Combined with the analysis of the theoretical interference performance value range, the astigmatism interference index of lens 1 is closer to the lower limit of the theoretical interference value range, so it is obviously better than lenses 2 and 3; in the comparison of the astigmatism contour map of lenses 2 and 3, lens 2 performs better in channel width, while lens 3 is better in astigmatism control. However, the traditional method cannot effectively quantify the advantages and disadvantages of the two. After using the evaluation method of the interference index, it can be obtained that the astigmatism interference performance of lenses 2 and 3 is very close, but because the interference index of lens 2 is closer to the lower limit of the interval, the interference performance of lens 2 is better than that of lens 3. Similarly, the interference caused by distortion of lens 1 is the smallest, while the interference caused by distortion of lens 2 is the largest.

[0158] Example 3

[0159] The method of this embodiment can also be used to evaluate the mid-distance interference of progressive multifocal spectacle lenses of different designs and different additional optical powers. Take three types of progressive lenses as examples, and refer to the distribution of their astigmatism contour lines. Fig. 9 , the specific parameters are shown in Table 3, the ADD of lenses 1 and 2 are 1.5D and 2.25D respectively, s is 3mm, hl is 13mm, the eye is the left eye lens, and lens 3 is the right eye lens, where s is 4mm, hl is 9mm, ADD = 2.0D, the internal deviation values ​​of the three lenses are all 2mm, and l is 10mm. The final astigmatism mid-distance interference calculation results can be obtained by this method.

[0160] Table 3 Parameters of progressive lenses with different additional focal powers

[0161]

[0162] From Table 3 and Fig. 9It can be seen that if the optical performance of lenses is evaluated according to the previous evaluation standards, it is often difficult to clearly distinguish the advantages and disadvantages of different ADD progressive lenses, and usually only the wearer's subjective feelings can be relied on to make judgments. After using the interference index method, it can be clearly found that the three lenses are very close in astigmatism interference performance: the channel, reference and blind zone interference indexes of lens 1 are 47.34, 9.05 and 11.87 respectively, and the astigmatism interference index is 68.26; the channel, reference and blind zone interference indexes of lens 2 are 49.4, 11.29 and 11.81 respectively, and the astigmatism interference index is 72.50; the channel, reference and blind zone interference indexes of lens 3 are 43.69, 12.65 and 13.50 respectively, and the astigmatism interference index is 69.84. According to the theoretical interference value range, lens 1 is better than lens 2, and lens 2 is better than lens 3. Since the two interference indexes of the three lenses are very close, in theory, the same wearer can adapt to the wearing effect of these three lenses.

[0163] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0164] The above is a detailed introduction to a progressive multifocal eyeglass lens and an evaluation method provided in the embodiments of the present application, and the principles and implementation methods of the present application are explained by using specific examples. The description of the above embodiments is only used to help understand the technical solution and its core idea of ​​the present application. Ordinary technicians in this field should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some of the technical features therein with equivalents; and these modifications or replacements do not cause the essence of the corresponding technical solution to deviate from the scope of the technical solution of the embodiments of the present application.

Claims

1. A method for evaluating a progressive multifocal spectacle lens, characterized in that: The following steps are involved: Dividing the surface of the eyeglass lens into regions to form interference evaluation regions; According to the interference evaluation area, obtaining an astigmatism interference index; Obtaining a distortion interference index according to the interference evaluation area; Based on the astigmatism interference index and the distortion interference index, an evaluation interference index is obtained, and combined with the theoretical interference performance value range of the spectacle lens, the performance of the spectacle lens is evaluated.

2. The method for evaluating a progressive multifocal spectacle lens according to claim 1, characterized in that: The step of dividing the surface of the eyeglass lens into regions to form interference evaluation regions further comprises: A rectangular coordinate system is constructed with the geometric center of the eyeglass lens as the origin O, the vertical direction as the x-axis, and the horizontal direction as the y-axis; Determine a distance reference point A and a near reference point C of the eyeglass lens respectively on both sides of the origin O on the x-axis; Determine a position B of the fitting cross of the spectacle lens on the x-axis, wherein the position B is located between the distance reference point A and the origin O; The surface of the eyeglass lens corresponding to the position A to the near reference point C is defined as the interference evaluation area.

3. The method for evaluating a progressive multifocal spectacle lens according to claim 2, characterized in that: The spectacle lens has a geometric center and an edge, and the step of obtaining the astigmatism interference index according to the interference evaluation area further includes: Dividing the interference evaluation area into a channel interference area, a reference interference area, and a blind interference area which are arranged in sequence from the optical center to the edge; Based on the channel interference area, the reference interference area and the blind area interference area, respectively obtain a channel interference index p1, a reference interference index p2 and a blind area interference index p3; Determine a weight coefficient w1 corresponding to the channel interference index p1, a weight coefficient w2 corresponding to the reference interference index p2, and a weight coefficient w3 corresponding to the blind spot interference index p3; The weight coefficient is combined with the corresponding interference index to obtain the astigmatism interference index, and the calculation expression of the astigmatism interference index is: Among them, P a N represents the astigmatism interference index; ind =3; p i represents any one of the channel interference index, the reference interference index, and the blind area interference index; i Represents the weight coefficients corresponding to the channel interference index, the reference interference index, and the blind spot interference index.

4. The method for evaluating a progressive multifocal spectacle lens according to claim 3, characterized in that: The calculation expression of the channel interference index p1 is: Among them, ω1 represents the average width at the visual transition position; ω min Indicates the minimum theoretical width; ω max Indicates the theoretical maximum width.

5. The method for evaluating a progressive multifocal spectacle lens according to claim 4, characterized in that: ω min The expression is: ω max The expression is: Among them, C th represents the astigmatism threshold; ADD represents the additional optical power from the distance reference point A to the near reference point C; s represents the distance between the position B and the origin O; h represents the distance between the distance reference point A and the near reference point C.

6. The method for evaluating a progressive multifocal spectacle lens according to claim 3, characterized in that: The calculation expression of the reference interference index p2 is: Among them, C ref Indicates the reference blind zone astigmatism; C ref | min Indicates the minimum value of astigmatism in the theoretical reference blind zone; C refmax Indicates the maximum value of theoretical reference blind zone astigmatism.

7. The method for evaluating a progressive multifocal spectacle lens according to claim 6, characterized in that: C refmin The expression is: C refmax The expression is: Where Δ represents the distance between the reference position and position B in the direction of the x-axis, and ADD represents the additional optical power from the distance reference point A to the near reference point C; s represents the distance between position B and the origin O; h represents the distance between the distance reference point A and the near reference point C; l represents the distance between the distance reference point A and the origin O.

8. The method for evaluating a progressive multifocal spectacle lens according to claim 3, characterized in that: The calculation expression of the blind spot interference index p3 is: Where k1 represents the distance coefficient of the position of the maximum astigmatism in the blind area; C nas Indicates the maximum astigmatism in the blind zone; C nas | min Indicates the minimum value of the maximum astigmatism in the theoretical blind zone; C nas | max Indicates the maximum value of the maximum astigmatism in the theoretical blind zone.

9. The method for evaluating a progressive multifocal spectacle lens according to claim 8, characterized in that: The expression of k1 is: C nas | min The expression is: C nas | max The expression is: C nas | max =2ADD; Among them, ADD represents the additional optical focal length from the distance reference point A to the near reference point C; s represents the distance between the position B and the origin O; h represents the distance between the distance reference point A and the near reference point C; l represents the distance between the distance reference point A and the origin O; x1 and y1 represent the coordinates of the position of the maximum astigmatism in the blind spot interference area.

10. The method for evaluating a progressive multifocal spectacle lens according to claim 3, characterized in that: The step of determining the weight coefficient w1 corresponding to the channel interference index p1, the weight coefficient w2 corresponding to the reference interference index p2, and the weight coefficient w3 corresponding to the blind spot interference index p3 further includes: Determine the initial weights of the channel interference index p1, the reference interference index p2, and the blind area interference index p3 by a systematic evaluation method; The initial weights are optimized by an adaptive genetic algorithm to obtain the corresponding weight coefficients w1, w2 and w3 after optimization.

11. The method for evaluating a progressive multifocal spectacle lens according to claim 3, characterized in that: The step of obtaining the distortion interference index according to the interference evaluation area further includes: Dividing the interference evaluation area into m circular areas, adjacent circular areas are tangent to each other; Based on the magnification of the m circular areas, the distortion interference index is obtained, and the calculation expression of the distortion interference index is: Where m represents the number of divided circular areas, and the range of m is a positive integer between 6 and 27; β i is the magnification of the i-th circular area, and is the average optical power of the i-th circular area.

12. The method for evaluating a progressive multifocal spectacle lens according to claim 11, characterized in that: The calculation expression for evaluating the interference index is: Wherein, P represents the evaluation interference index.

13. The method for evaluating a progressive multifocal spectacle lens according to claim 12, characterized in that: The theoretical interference performance value interval ranges from 0 to 100.

14. A spectacle lens, characterized in that: The method is evaluated by using any one of the evaluation methods of claims 1 to 13.

Images