Method of designing, method of manufacturing, and design system for eyeglass lenses

Abstract

Provided is a technique that is stable with respect to changes in the amount of aberration when combining the aberration of the eye and the aberration of the spectacle lens in the spectacle lens even if the aberration of at least one of the eye and the spectacle lens in the spectacle changes due to the physical characteristics of the wearer. Provided is a spectacle lens design method and related techniques in which, in a case where the degree of change in the aberration distribution of at least one of the eye and the spectacle lens in the spectacle due to the physical characteristics of the wearer is large, a spectacle lens in which the non-rotationally symmetric property of the aberration distribution in a region in a prescribed width range centered on each point on the principal meridian of the spectacle lens is weak is obtained as a design solution, and in a case where the degree of change is small, a spectacle lens in which the non-rotationally symmetric property in the region is strong is obtained as a design solution.

Description

Technical Field

[0001] This invention relates to a method for designing spectacle lenses, a method for manufacturing them, and a design system. Background Technology

[0002] A method for manufacturing lenses that compensate for eye aberrations in refractive errors has been disclosed (Patent Document 1). Moreover, Patent Document 1 describes the correction of at least one higher-order aberration in at least one visual direction.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent No. 5096662 Summary of the Invention

[0006] The technical problem that the invention aims to solve

[0007] The technology described in Patent Document 1, which is prior art, compensates for the wearer's eye image compensation. On the other hand, the inventors of this application, after diligent research, discovered that the wearer's physical characteristics may prevent this compensation from functioning.

[0008] Details will be explained later, but for example, in cases where the patient has dry eye syndrome, the shape of the tear film on the corneal surface changes due to the condition. This change alters the distribution of aberrations in the eye.

[0009] Furthermore, for example, when the height of the eyeglass frames on the left and right ears differs due to body characteristics, the following changes occur: as the wearing time increases, the difference in height between the left and right ears causes the eyeglasses to deviate from their correct position about the wearer's front-back direction (optical axis). This change alters the aberration distribution of the eyeglass lenses.

[0010] In this specification, aberrations may be considered as disturbances in the wavefront of light originating from the eye or lens. As a wave property, aberrations are canceled out by combining waves with opposite signs. If waves with non-opposite signs are combined, the aberrations are sometimes canceled out and sometimes not.

[0011] The object of this invention is to provide a technique that stabilizes the change in the amount of aberration when the aberrations of the eye and the eyeglass lens are combined, even if the aberrations of at least one of the eyes and the eyeglass lens change due to the wearer's physical characteristics. In this specification, "stabilized" means that even if such a change occurs, the amount of aberration when the aberrations of the eye and the eyeglass lens are combined is less likely to change than before.

[0012] Means for solving technical problems

[0013] After diligently researching the aforementioned technical problems, the inventors of this application arrived at the following theory.

[0014] The inventors of this application observed changes in aberrations caused by human physical characteristics and determined that these changes should be appropriately correlated with the lenses of the eyeglasses worn. They discovered that these aberration changes were primarily caused by rotation of the aberration distribution. For example, the tear film on the human cornea often exhibits a motion similar to rotation. This is because the unevenness created by the tear film at the corneal margin shifts downwards due to gravity or changes in position (viewed from the center of the cornea) due to blinking.

[0015] Therefore, we mainly focus on the changes in aberration distribution caused by rotation and examine the correlation between this aberration distribution and the aberration distribution of the spectacle lens.

[0016] For example, suppose the spectacle lens has a rotationally symmetric aberration distribution. In this case, even if the wearer's physical characteristics can significantly alter the aberration distribution of the spectacle lens during wear, the amount of aberration when combining the aberrations of the wearer's eye and the spectacle lens remains unchanged. This is the same as if the wearer's physical characteristics could significantly alter the aberration distribution of the eye; the amount of aberration when combining the aberrations of the wearer's eye and the spectacle lens remains unchanged.

[0017] Based on the above theory, it was found that even when the aberration distribution of at least one of the eyes and the lenses being worn changes significantly due to the wearer's physical characteristics, as long as the lenses have rotationally symmetric or nearly rotationally symmetric aberration distributions, the change in the amount of aberration when combining the aberrations of the eyes and lenses becomes less (i.e., becomes stable).

[0018] Hereinafter, aberration distributions that deviate from rotational symmetry will also be referred to as "non-rotational symmetry". In this specification, a case with a large degree of deviation from rotational symmetry is referred to as "strong non-rotational symmetry", and conversely, a case that is close to rotational symmetry is referred to as "weak non-rotational symmetry". In addition, the so-called "change in aberration distribution" does not only refer to the change in the distribution itself, but also includes the changes caused by rotation or movement around the axis.

[0019] In other words, the inventors of this application have discovered a technique that, unlike existing technologies, does not determine the wavefront of eyeglass lenses by suppressing uneven distribution of aberrations based on the eye's wavefront. Instead, it considers the temporal changes in aberrations accompanying the wearer's physical characteristics, thereby reducing the variation in the amount of aberrations when the aberrations of the eye and eyeglass lenses are combined. Hereinafter, the "temporal changes" of aberrations accompanying the wearer's physical characteristics will also be referred to as "changes." Furthermore, such changes include, for example, changes caused by the gradual drying of tears on the cornea, or instantaneous changes caused by blinking, and also include situations where the glasses gradually become ill-fitting due to the contours of the face, or instantaneous changes in wearing status.

[0020] The various embodiments of the present invention, based on the above findings, are as follows.

[0021] The first aspect of the present invention is a method for designing spectacle lenses, wherein,

[0022] When the aberration distribution of the eye and at least one of the eyeglass lenses varies greatly due to the wearer's physical characteristics, the design solution is to obtain an eyeglass lens with weak non-rotational symmetry in the aberration distribution within a specified width region centered on each point on the principal meridian of the eyeglass lens.

[0023] When the degree of change is small, the spectacle lens with strong non-rotational symmetry in the region is obtained as the design solution.

[0024] The second aspect of the present invention is based on the eyeglass lens design method described in the first aspect.

[0025] The wearer's physical characteristics refer to at least one of the following: the degree of asymmetry in the shape of the nose when viewed from the front, the height difference in the position of the glasses on the left and right ears, and the shape stability of the wearer's tear film.

[0026] The third aspect of the present invention is based on the eyeglass lens design method described in the first or second aspect.

[0027] When the index quantifying the degree of change in aberration distribution of the eye and at least one of the lenses being worn due to the wearer's physical characteristics is set as Di, the baseline value of Di is set as Ds, and the index quantifying the non-rotational symmetry in the aberration distribution of the lenses is set as Li,

[0028] When Di is larger than Ds, the design solution is to obtain spectacle lenses with lower Li.

[0029] When Di is below Ds, the eyeglass lens with high Li is taken as the design solution.

[0030] The fourth aspect of the present invention is based on the eyeglass lens design method described in the third aspect.

[0031] The so-called obtaining the eyeglass lens as a design solution involves selecting one from multiple design solutions that are different from Li.

[0032] The fifth aspect of the present invention is based on the eyeglass lens design method described in the third or fourth aspect.

[0033] When the shape of the tear film on the corneal surface changes significantly due to blinking, causing substantial variations in the eye's aberration distribution, a spectacle lens with weak non-rotational symmetry in the aberration distribution within the specified region is selected as the design solution.

[0034] When the change in the shape of the tear film on the corneal surface accompanying the wearer's blink causes a small change in the aberration distribution of the eye, a spectacle lens with strong non-rotational symmetry in the region is obtained as the design solution.

[0035] The sixth aspect of the present invention is based on the eyeglass lens design method described in the fifth aspect.

[0036] Di is at least an indicator that quantifies the non-rotational symmetry of the aberration distribution around the optical axis of the pupil-corresponding portion of the wearer's cornea.

[0037] The seventh aspect of the present invention is based on the eyeglass lens design method described in the sixth aspect.

[0038] When the index before the wearer blinks is set as Ei and the index after blinking is set as Ei´, Di and Li are indices that quantify the non-rotational symmetry of the aberration distribution of the eye.

[0039] Di is an index represented by the following Equation 1.

[0040]

[0041] Li is an index represented by the following Equation 2.

[0042]

[0043] E and E' represent the polar coordinates of the Zernike aberration coefficients of the wearer's eye, L represents the polar coordinates of the Zernike aberration coefficients of the eyeglass lens, E is related to the shape of the tear film on the corneal surface before the wearer blinks, E' is related to the shape of the tear film on the corneal surface after the wearer blinks, m represents the value of the circumferential direction, and n represents the value of the radial direction.

[0044] The eighth aspect of the present invention is based on the eyeglass lens design method described in any one of the third to seventh aspects.

[0045] Ds is determined based on at least one of the following: standard or average aberrations related to the wearer's eyeball obtained statistically or academically; the wearer's eyeball rotation; the wearer's pupillary diameter variation; the wearer's age; the environment or purpose in which the wearer uses the glasses; and the time elapsed since the wearer's last visit to the optician.

[0046] The ninth aspect of the present invention is based on the eyeglass lens design method described in any one of the third to eighth aspects.

[0047] Based on the difference between Di and Ds, the spectacle lens is obtained as the design solution.

[0048] The tenth aspect of the present invention is based on the eyeglass lens design method described in any one of the first to ninth aspects.

[0049] The eyeglass lenses are progressive lenses.

[0050] The eleventh aspect of the present invention is a method for manufacturing spectacle lenses, wherein the spectacle lenses are designed using the spectacle lens design method described in any one of the first to tenth aspects.

[0051] The twelfth aspect of the present invention is a design system for eyeglass lenses, comprising a design unit, characterized in that...

[0052] When the aberration distribution of the eye and at least one of the eyeglass lenses varies greatly due to the wearer's physical characteristics, the design solution is to obtain an eyeglass lens with weak non-rotational symmetry in the aberration distribution within a specified width region centered on each point on the principal meridian of the eyeglass lens.

[0053] When the degree of change is small, the spectacle lens with strong non-rotational symmetry in the region is obtained as the design solution.

[0054] The thirteenth aspect of the present invention is based on the spectacle lens design system described in the twelfth aspect.

[0055] The wearer's physical characteristics refer to at least one of the following: the degree of asymmetry in the shape of the nose when viewed from the front, the height difference in the position of the glasses on the left and right ears, and the shape stability of the wearer's tear film.

[0056] The fourteenth aspect of the present invention is based on the spectacle lens design system described in the twelfth or thirteenth aspect.

[0057] When the index quantifying the degree of change in the aberration distribution of at least one of the eyes and the worn spectacle lenses due to the wearer's physical characteristics is set as Di, the baseline value of Di is set as Ds, and the index quantifying the non-rotational symmetry in the aberration distribution of the spectacle lenses is set as Li,

[0058] When Di is larger than Ds, the design solution is to obtain spectacle lenses with lower Li.

[0059] When Di is below Ds, the eyeglass lens with high Li is taken as the design solution.

[0060] The fifteenth aspect of the present invention is based on the spectacle lens design system described in the fourteenth aspect.

[0061] The so-called obtaining the eyeglass lens as a design solution involves selecting one from multiple design solutions that are different from Li.

[0062] The sixteenth aspect of the present invention is based on the spectacle lens design system described in the fourteenth or fifteenth aspect.

[0063] When the shape of the tear film on the corneal surface changes significantly due to blinking, causing substantial variations in the eye's aberration distribution, a spectacle lens with weak non-rotational symmetry in the aberration distribution within the specified region is selected as the design solution.

[0064] When the change in the shape of the tear film on the corneal surface accompanying the wearer's blink causes a small change in the aberration distribution of the eye, a spectacle lens with strong non-rotational symmetry in the region is obtained as the design solution.

[0065] The seventeenth aspect of the present invention is based on the spectacle lens design system described in the sixteenth aspect.

[0066] Di is at least an indicator that quantifies the non-rotational symmetry of the aberration distribution around the optical axis of the pupil-corresponding portion of the wearer's cornea.

[0067] The eighteenth aspect of the present invention is based on the spectacle lens design system described in the seventeenth aspect.

[0068] When the index before the wearer blinks is set as Ei and the index after blinking is set as Ei´, Di and Li are indices that quantify the non-rotational symmetry related to the aberration distribution of the eye.

[0069] Di is an index represented by the following Equation 1.

[0070]

[0071] Li is an index represented by the following Equation 2.

[0072]

[0073] E and E' represent the polar coordinates of the Zernike aberration coefficients of the wearer's eye, L represents the polar coordinates of the Zernike aberration coefficients of the eyeglass lens, E is related to the shape of the tear film on the corneal surface before the wearer blinks, E' is related to the shape of the tear film on the corneal surface after the wearer blinks, m represents the value of the circumferential direction, and n represents the value of the radial direction.

[0074] The nineteenth aspect of the present invention is based on the spectacle lens design system described in any one of aspects fourteen to eighteen.

[0075] Ds is determined based on at least one of the following: standard or average aberrations related to the wearer's eyeball obtained statistically or academically; the wearer's eyeball rotation; the wearer's pupillary diameter variation; the wearer's age; the environment or purpose in which the wearer uses the glasses; and the time elapsed since the wearer's last visit to the optician.

[0076] The twentieth aspect of the present invention is based on the spectacle lens design system described in any one of the fourteenth to nineteenth aspects.

[0077] Based on the difference between Di and Ds, the spectacle lens is obtained as the design solution.

[0078] The twenty-first aspect of the present invention is based on the spectacle lens design system described in any one of aspects twelfth to twentieth.

[0079] The eyeglass lenses are progressive lenses.

[0080] Other embodiments of the present invention that can be combined with the above-described methods are as follows.

[0081] When calculating Di, the aberration of n=1 is only caused by the prism and is unrelated to the image resolution, so it can be ignored.

[0082] When calculating Di, the aberrations of |m|=2 and n=2 are astigmatism, which are aberrations that users are already accustomed to even with monofocal lenses and therefore can be ignored.

[0083] One aspect of the present invention can also be applied to progressive refractive power lenses that transmit non-point aberrations but are added to the intermediate and near portions instead of the distance portion. One aspect of the present invention can also be used as a material for determining the appropriate degree of non-point aberration transmission.

[0084] Invention Effects

[0085] According to the present invention, even if the aberrations of at least one of the eyes and the lenses being worn change due to the wearer's physical characteristics, the change in the amount of aberration when the aberrations of the eyes and the lenses are combined remains stable relative to the change. Attached Figure Description

[0086] Figure 1A This is a diagram showing the refractive power distribution (m=0, n=2) of lens 1. Figure 1B This is a graph showing the non-point aberration distribution of lens 1 (|m|=2, n=2). Figure 1C This is a diagram showing the coma aberration distribution of lens 1 (|m| = 1, n = 3). Figure 1D This is a graph showing the Trefoil aberration distribution (|m|=3, n=3) of lens 1.

[0087] Figure 2A This is a diagram showing the refractive power distribution (m=0, n=2) of lens 2. Figure 2B This is a graph showing the non-point aberration distribution of lens 2 (|m| = 2, n = 2). Figure 2C This is a diagram showing the coma aberration distribution of lens 2 (|m| = 1, n = 3). Figure 2D This is a graph showing the Trefoil aberration distribution of lens 2 (|m| = 3, n = 3).

[0088] Figure 3A This is a diagram showing the refractive power distribution (m=0, n=2) of lens 3. Figure 3B This is a graph showing the non-point aberration distribution of lens 3 (|m|=2, n=2). Figure 3C This is a diagram showing the coma aberration distribution of lens 3 (|m| = 1, n = 3). Figure 3D This is a graph showing the Trefoil aberration distribution (|m|=3, n=3) of lens 3.

[0089] Figure 4 This is a block diagram illustrating the structure of a spectacle lens design system according to one embodiment of the present invention.

[0090] Figure 5 This is a flowchart of a spectacle lens design system according to one embodiment of the present invention. Detailed Implementation

[0091] The following describes one embodiment of the present invention. In this specification, "~" refers to a value above and below a specified value.

[0092] <Design Methods for Eyeglass Lenses>

[0093] The design method of spectacle lenses according to one embodiment of the present invention is as follows.

[0094] "When the aberration distribution of the eye and at least one of the eyeglass lenses changes significantly due to the wearer's physical characteristics, a design solution is obtained by finding an eyeglass lens with weak non-rotational symmetry in the aberration distribution within a specified width region centered on each point on the principal meridian of the eyeglass lens."

[0095] When the degree of change is small, the spectacle lens with strong non-rotational symmetry in the region is obtained as the design solution.

[0096] In this manual, the "optical axis" is equivalent to the normal at the center of each optical surface.

[0097] The "center" mentioned above is also called the "lens center." The "lens center" refers to the geometric center, optical center, or center of curvature of the eyeglass lens. This instruction manual uses the center of curvature as an example. This instruction manual uses the scenario of the wearer viewing through the center of the lens from the front as an example.

[0098] As described in "Means for Solving Technical Problems," according to the above structure, even when the aberration distribution of at least one of the eyes and the eyeglass lenses changes significantly due to the wearer's physical characteristics, the change in the amount of aberration when combining the aberrations of the eyes and the eyeglass lenses is reduced (i.e., becomes stable). Regarding the reduction in the amount of aberration, the type of aberration is not particularly limited, but higher-order aberrations are preferred, meaning aberrations of order 3 or higher.

[0099] The "specified width" of the aforementioned area is a horizontal width smaller than the lens radius, preferably (for example) around 10 mm, and more preferably the width projected onto the lens surface to represent the pupil diameter. This can be the size on the lens surface corresponding to a pupil diameter of 2 mm (maximum diameter 5 mm).

[0100] The “points” mentioned above refer to all (any) points on the principal meridian.

[0101] Hereinafter, preferred examples and variations of a method for designing eyeglass lenses according to an embodiment of the present invention will be described.

[0102] The wearer's physical characteristics include, for example, the degree of asymmetry in the shape of the nose when viewed from the front, the difference in height of the eyeglass frames on the left and right ears, and the stability of the wearer's tear film shape.

[0103] When the nose shape is highly asymmetrical when viewed from the front, the following phenomenon may occur: When wearing glasses, they appear to be in the correct position when viewed from the front. However, over time, similar to the asymmetrical shape of the nose, the glasses may deviate from the correct position about the wearer's front-to-back direction (optical axis).

[0104] When there is a significant difference in the height of the eyeglass frames worn on the left and right ears, the same phenomenon described above may occur. When wearing the glasses, they appear to be in the correct position when viewed from the front. However, over time, the following changes occur: as the wearing time increases, the glasses deviate from the correct position about the wearer's front-back direction (optical axis direction) due to the difference in the height of the frames worn on the left and right ears.

[0105] Low tear film shape stability in wearers refers to cases where the wearer has dry eye syndrome. In cases of dry eye syndrome, the shape of the tear film on the cornea is unstable. Specifically, the thickness of the tear film on the cornea is uneven. Furthermore, the shape of the tear film on the corneal surface easily changes with blinking. As a result, in cases of dry eye syndrome, the distribution of aberrations in the eye changes significantly over time.

[0106] To facilitate understanding of one embodiment of the present invention, examples of cases where the patient has dry eye syndrome and cases where the patient does not have dry eye syndrome will be given below. In this case, one embodiment of the present invention is shown as follows.

[0107] "A method for designing spectacle lenses, where the degree of change in the aberration distribution of the eye is large due to the shape change of the tear film layer on the corneal surface accompanying the wearer's blinking, obtains a spectacle lens with weak non-rotational symmetry of the aberration distribution in the said region as the design solution."

[0108] When the change in the shape of the tear film on the corneal surface accompanying the wearer's blink causes a small change in the distribution of aberrations in the eye, a spectacle lens with strong non-rotational symmetry in the aforementioned region is selected as the design solution.

[0109] The following example, when describing "the degree of change in the aberration distribution of the eye and at least one of the lenses worn due to the wearer's physical characteristics," is "the degree of change in the aberration distribution of the eye due to the change in the shape of the tear film on the corneal surface accompanying the wearer's blink."

[0110] Preferably, the method involves quantifying the degree of change in the aberration distribution of at least one of the eyes and the lenses being worn due to the wearer's physical characteristics, as well as quantifying the non-rotational symmetry in the aberration distribution of the lenses. An example incorporating this quantification process is given below.

[0111] E and L represent the polar coordinates of the Zernike aberration coefficients of the wearer's eye and the spectacle lens, respectively; m is the value representing the order in the circumferential direction; and n is the value representing the order in the radial direction. Furthermore, let θ be the rotation angle of the wearer's eye around the optical axis, and γ be the rotation angle of the spectacle lens around the optical axis. Then, the sum of the squares of the aberrations of the eye and the spectacle lens is expressed by Equation 3 below.

[0112]

[0113] It is important to note that the sum of squares is used because, according to the orthogonality of the Zernike polynomial, it corresponds to the sum of squares of the total aberrations and to the intensity of the light spot formed on the retina. In this specification, "light spot" refers to the range from the peak to the first dark ring in the distribution of light formed on the retina by a portion of the light from an object point through a spectacle lens and the eye's optical system. Furthermore, in this specification, the sum of the energies within this range is referred to as "light spot intensity."

[0114] Taking the partial derivative of Equation 3 above at each rotation angle, we get Equation 4 below. Equation 4 below shows the change in the sum of squares of aberrations of the eye and spectacle lenses caused by rotation.

[0115]

[0116] Ideally, the best eyeglass lens design would minimize the variation in the sum of squares of Equation 4 above. However, calculating the above formula for each wearer individually offers no advantage in terms of computational time and resources. As previously mentioned, the direction of vision (eyeball direction) when measuring the various parameters for the wearer is naturally different from the direction of vision when wearing eyeglass lenses in daily life. Therefore, minimizing the variation in the sum of squares of Equation 4 above is less meaningful.

[0117] Therefore, relevant parameters of the eye and the spectacle lens are extracted from Equation 4 above. The relevant parameters of the eye in Equation 4 are set as Ei, representing the non-rotational symmetry of the aberration distribution of the wearer's eye about the optical axis. The relevant parameters of the spectacle lens in Equation 4 are set as Li, representing the non-rotational symmetry of the aberration distribution of the spectacle lens.

[0118] Ei is an index represented by the following Equation 5.

[0119]

[0120] Li is an index represented by the following Equation 2.

[0121]

[0122] In order to quantify the degree of change in the distribution of ocular aberrations due to the change in the shape of the tear film on the corneal surface accompanying the wearer's blink, the following is considered.

[0123] With the aberration measured after the wearer blinks set as Ei´, the degree of the above change is expressed by the following formula.

[0124]

[0125] Equation 1 above is represented as Di (dry eye index).

[0126] It is worth noting that the method for obtaining Di is just one example, and there are no limitations on the method. For example, one can refer to the value of the degree of dry eye calculated by a dry eye tester. In addition, a higher Di value can be specified when dry eye is diagnosed by a doctor.

[0127] The following are specific examples concerning the examinee as a customer (the future wearer).

[0128] The index Di of the non-rotational symmetry of wearer A's eye is an index that quantifies the non-rotational symmetry of the aberration distribution around the optical axis of the pupil-corresponding portion of the cornea of ​​the wearer's eye. The so-called "pupil-corresponding portion of the cornea" is the part of the cornea within a diameter of at least 2 mm (maximum diameter 5 mm) from the center of the pupil.

[0129] The wavefront and aberrations of the eye (cornea) can be obtained by methods described in the prior art or known methods.

[0130] The wavefront and aberrations of spectacle lenses can be obtained using methods described in the prior art or known methods. Specifically, for example, the interference fringes of light transmitted from the object-side surface of the spectacle lens towards the eye can be measured using a Fujinon F601 manufactured by Fujifilm Corporation, a small laser interferometer employing a Fizeau-type interferometry method. After obtaining the interference fringe measurement results, a known fringe analysis algorithm is applied to the measurement results to calculate the wavefront data of light passing through each point of the spectacle lens. The collection of wavefront-specific data for each point corresponds to the wavefront data of the light transmitted through the spectacle lens. Therefore, by plotting the wavefront-specific data for each point, the wavefront data is obtained.

[0131] The changes in higher-order aberrations of wearer A's eye are as follows (unit: D (diopter), units omitted below).

[0132] m=2, n=2: Non-point aberration change of 0.12

[0133] When m=1 and n=3: the change in coma aberration is 0.02.

[0134] m=3, n=3: Trefoil aberration change 0.04

[0135] m=2, n=4: Higher-order nonpoint aberrations change by 0.06

[0136] m=4, n=4: Tetrafoil aberration change 0.07

[0137] The aberrations changed very little in subsequent iterations (<0.001), so they are omitted from the record. The aberrations are the same for the unrecorded iterations (where n ≥ 5).

[0138] When calculating Di, the aberration at n=1 is caused solely by the prism and is unrelated to the image resolution, so it can be ignored.

[0139] When calculating Di, the aberrations at m=2 and n=2 represent the astigmatism correction component. If wearer A is not a first-time user of eyeglasses, their previous eyeglasses should already contain astigmatism correction. That is, it can be assumed that wearer A is already accustomed to astigmatism correction. Therefore, it can be considered that even if the aberrations of the astigmatism correction component change when the aberrations of the eye and eyeglasses are combined, wearer A will hardly perceive the change. Therefore, when calculating Di, it is acceptable to ignore the aberrations at m=2 and n=2. An example is given below.

[0140] In addition, wearer A's Di (dry eye index) is as follows.

[0141] Di=0.02+0.04+0.06+0.07

[0142] =0.19

[0143] It is worth noting that the baseline value for Di is set as Ds. In this example, Ds is the average of the individual Di values ​​of the applicant's customers. This is just one example; Ds is not limited to this average value. For example, it could be the average value of individual wearers stored in big data on the internet, or it could be the most frequent value.

[0144] The baseline values ​​are as follows (units omitted).

[0145] m=2, n=2: Non-point aberration change of 0.10

[0146] When m=1 and n=3: the change in coma aberration is 0.07.

[0147] m=3, n=3: Trefoil aberration change 0.02

[0148] m=2, n=4: Higher-order nonpoint aberrations change by 0.03

[0149] m=4, n=4: Tetrafoil aberration change 0.01

[0150] Ds=0.07+0.02+0.03+0.01

[0151] =0.13

[0152] Wearer A's Di is greater than the reference value Ds. That is, wearer A's degree of variation is higher than the average. According to the design method of the spectacle lens of the present invention, the effect of the present invention is achieved by obtaining a spectacle lens with low Li as the design solution for wearer A. If Di is below Ds, a spectacle lens with high Li is obtained as the design solution.

[0153] It is worth noting that, in one embodiment of the present invention, the so-called "Li low" when Di > Ds refers to a value of Li lower than that when Di ≦ Ds. That is, "Li high" and "Li low" can be relative to each other. On the other hand, the reference value Ls of Li can also be set the same as the reference value Ds of Di, and the Ls can be evaluated as high or low.

[0154] Ls can be the average of each Li among the applicant's customers, for example, the average of each wearer stored in big data via the internet, or the most frequent value. Alternatively, since it is a design solution for an eyeglass lens within a specified product group, a design solution using the median value from multiple Li within the product group can also be used.

[0155] It is worth noting that in one embodiment of the present invention, the cases of Di > Ds and Di ≦ Ds can also be divided into cases of Di ≧ Ds and Di < Ds. In this case, a value slightly lower than Ds can be used as the new Ds. As a result, the case of dividing the value using Ds as the threshold remains unchanged.

[0156] The so-called "spectacle lens design" can involve designing the aberration distribution (and refractive power distribution, hereinafter omitted) of the spectacle lens after accepting the above results (Di > Ds), or it can modify an existing aberration distribution. Alternatively, multiple basic designs (design solutions) of aberration distributions can be prepared in advance, and one of these basic designs, representing different aberration distributions in Li, can be included in the "spectacle lens design." This method reduces computational load and cuts down on design costs and time.

[0157] The term "obtained as a design solution" can, for example, include a design with the aforementioned aberration distribution when Li is a low-resolution spectacle lens, or it can include a correction to an existing aberration distribution, or it can include selecting one from multiple basic designs with different Li values. Alternatively, these can be output as data. In this case, it is also referred to as "taking Li as a low-resolution spectacle lens as a design solution and outputting the data."

[0158] The aforementioned "selection of spectacle lenses" is a configuration created from an idea completely opposite to that of the prior art. In detail, in contrast to the prior art which focuses on the highest performance under assumed conditions for a given eye, the present invention focuses on the lowest performance under non-assumed conditions.

[0159] The "basic design" of this specification refers to the aberration distribution in a progressive lens before adding inward projection. Specifically, the Y-axis, with the center of the spectacle lens as the origin, corresponds to the principal meridian. In this case, the X-axis is horizontal, and the Z-axis is the optical axis (front). Three different basic designs are then given examples. The aberration amounts listed in each basic design are the aberrations within a defined width centered on points along the principal meridian of the spectacle lens. However, the aberration amounts listed in each basic design do not include the aberrations of the eye. A width of 10 mm has been previously cited for this region, but the invention is not limited to this.

[0160] On the other hand, the present invention is not limited to the form based on the aberration distribution before the increase in inward amount, and multiple design solutions after setting the principal meridian with the increase in inward amount can be prepared in advance.

[0161] Furthermore, the design of this invention is not limited to a progressive lens having a near-field section for identifying near distances, a far-field section for identifying distances farther than near distances, and an intermediate section connecting the two sections with a gradually changing power. For example, it may only include a near-field section for identifying near distances, or it may be an eyeglass lens with a gradually changing power (progressive lens), or a bifocal lens, or a monofocal lens.

[0162] In the case of a single-focal lens, the principal meridian is a straight line (e.g., the Y-axis) that passes through the axis of rotational symmetry in the vertical (longitudinal) direction.

[0163] In the case of progressive lenses (progressive multifocal lenses), the principal meridian mentioned above, which increases the inward amount, is also called the principal gaze line. The principal gaze line can be a straight line or a curve, as long as it is determined by the fitting point FP, the distance power measurement reference point F, and the near power measurement reference point N. These positions can be identified by hidden markings set on the eyeglass lens.

[0164] Using an example of choosing one of several basic designs that are different from each other, three basic designs are prepared as follows.

[0165] Figure 1A This is a diagram showing the refractive power distribution (m=0, n=2) of lens 1.

[0166] Figure 1B This is a graph showing the non-point aberration distribution of lens 1 (|m|=2, n=2).

[0167] Figure 1C This is a diagram showing the coma aberration distribution of lens 1 (|m| = 1, n = 3).

[0168] Figure 1DThis is a graph showing the Trefoil aberration distribution (|m|=3, n=3) of lens 1.

[0169] However, please note that the dimensions are 50mm in length and 50mm in width.

[0170] Furthermore, in Figures 1 through 3, the white areas represent regions with high aberrations, and the black areas represent regions with low aberrations. The aberration distribution diagrams will be presented in the same manner below.

[0171] The aberrations of lens 1 are as follows (units omitted).

[0172] m=2, n=2: Non-point aberration 0.03

[0173] m=1, n=1: Coma aberration 0.35

[0174] m=3, n=3: Trefoil aberration 0.32

[0175] Li=2×0.03+1×0.35+3×0.32

[0176] =1.37

[0177] Figure 2A This is a diagram showing the refractive power distribution (m=0, n=2) of lens 2.

[0178] Figure 2B This is a graph showing the non-point aberration distribution of lens 2 (|m| = 2, n = 2).

[0179] Figure 2C This is a diagram showing the coma aberration distribution of lens 2 (|m| = 1, n = 3).

[0180] Figure 2D This is a graph showing the Trefoil aberration distribution of lens 2 (|m| = 3, n = 3).

[0181] However, please note that the dimensions are 50mm in length and 50mm in width.

[0182] In lens 2, non-point aberrations are increased instead of reduced Trefoil aberrations in the central region along the principal meridian in lens 1. The aberration amounts in lens 2 are as follows (units omitted).

[0183] m=2, n=2: Non-point aberration 0.06

[0184] m=1, n=1: Coma aberration 0.38

[0185] m=3, n=3: Trefoil aberration 0.25

[0186] Li=2×0.06+1×0.38+3×0.25

[0187] =1.25

[0188] Figure 3A This is a diagram showing the refractive power distribution (m=0, n=2) of lens 3.

[0189] Figure 3B This is a graph showing the non-point aberration distribution of lens 3 (|m|=2, n=2).

[0190] Figure 3C This is a diagram showing the coma aberration distribution of lens 3 (|m| = 1, n = 3).

[0191] Figure 3D This is a graph showing the Trefoil aberration distribution (|m|=3, n=3) of lens 3.

[0192] However, please note that the dimensions are 50mm in length and 50mm in width.

[0193] In lens 3, trefoil aberration and non-point aberration increase in the central region along the principal meridian of lens 1. Correspondingly, non-point aberration decreases away from the principal meridian. This means that even if the wearer's gaze passes through the periphery of the lens, the recognized image is less likely to wobble or distort. The aberrations of lens 3 are as follows (units omitted).

[0194] m=2, n=2: Non-point aberration 0.06

[0195] m=1, n=1: Coma aberration 0.38

[0196] m=3, n=3: Trefoil aberration 0.39

[0197] Li=2×0.06+1×0.38+3×0.39

[0198] =1.67

[0199] Wearer A's Di is larger than the reference value Ds. Therefore, for wearer A, a lens with low Li is needed as the design solution. The result is the selection of lens 2 for wearer A.

[0200] The aberrations of wearer B's eye are as follows (units omitted).

[0201] When m=2 and n=2: the change in non-point aberration is 0.14.

[0202] When m=1 and n=3: the change in coma aberration is 0.02.

[0203] When m=3 and n=3: Trefoil aberration change is 0.03

[0204] m=2, n=4: Higher-order nonpoint aberrations change by 0.02

[0205] m=4, n=4: Tetrafoil aberration change 0.01

[0206] Furthermore, wearer A's Di is as follows.

[0207] Di=0.02+0.03+0.02+0.01

[0208] =0.08

[0209] Wearer B's Di is smaller than the reference value Ds. Therefore, for wearer B, a lens with high Li is needed as the design solution. The result is the selection of lens 3 for wearer B.

[0210] In this example, the basic design of lenses 1 to 3 is prepared, but you can also choose lenses with a lower Li from existing eyeglass lenses.

[0211] The scope of the technology of the present invention is not limited to the above-described embodiments, but also includes various modifications or improvements made to the scope of the specific effects that can be derived by the constituent elements of the invention or their combination.

[0212] The above example uses indicators for dry eye syndrome, but the present invention is not limited thereto. For example, the degree of asymmetry in the shape of the nose and the height difference in the position of the eyeglass frames on the left and right ears can also be indices obtained and non-rotational symmetry quantified, just like in the case of dry eye syndrome.

[0213] In the example above, Di is specified only by the aberration amount, but other parameters can be added, or other parameters can be used instead of the aberration amount to determine Ei. Such parameters include at least one of the following: the wearer's eye rotation degree, the wearer's pupil diameter variation degree, the wearer's age, the environment or purpose in which the wearer uses the glasses, and the time elapsed since the wearer's last visit to the optician.

[0214] If the wearer's eye rotation degree and / or the wearer's pupil diameter change is small, the change in aberration when the eye and the eyeglass lens combine is small, so the Di value can be reduced according to the eye rotation degree.

[0215] If the wearer is older, the non-rotational symmetry of the eye wave surface is more likely to be stronger, so the value of Di can be increased according to the wearer's age.

[0216] If a long period of time (years and months) has passed since the wearer last visited the optician, the non-rotational symmetry of the eye's wavefront is more likely to increase, so the Di value can be increased based on that time.

[0217] Furthermore, Di can be specified not only by the aberration amount, but also by at least one of the wearer's age and the time elapsed since the wearer's last visit to the optician. Because with these two parameters, it is possible to infer the strength of the non-rotational symmetry of the wearer's eye aberration distribution around the optical axis.

[0218] In addition to or instead of Di, Ds can be based on at least one of the following statistically or academically obtained standard or average aberrations related to the wearer's eyeball, the wearer's ocular rotation, the wearer's pupillary diameter variation, the wearer's age, the environment or purpose of the wearer's use of the glasses, and the time elapsed since the wearer's last visit to the optician. For example, Di is more likely to be higher in older wearers. In this case, by replacing the value of Di with a lower threshold value (the boundary value) for Ds, it becomes easier to make Di > Ds, resulting in easier selection of lenses with lower Li values.

[0219] Furthermore, an example of an eyeglass lens is a progressive lens having a distance section, a near section, and an intermediate section. Even within such progressive lenses, an embodiment of the present invention can be applied to progressive lenses that do not add non-point aberration transmission in the distance section but in the intermediate and near sections (WO2020 / 067522, WO2020 / 067523). An embodiment of the present invention can be used as a material for determining the appropriate degree of non-point aberration transmission. The entire description in both documents is incorporated into this specification.

[0220] <Methods for Manufacturing Spectacle Lenses>

[0221] This invention is also applicable to methods for manufacturing spectacle lenses. Specifically, spectacle lenses designed according to the above-described spectacle lens design method can be manufactured using known methods. It is worth noting that the term "spectacle lens supply method" can be used as an expression referring to at least any of the above-described design method and this manufacturing method. Similarly, the following system can also be referred to as a "spectacle lens supply system."

[0222] <Eyeglass Lens Design System>

[0223] The eyeglass lens design system according to one embodiment of the present invention is as follows. It is worth noting that content repeated in the section on "Eyeglass Lens Design Method" is omitted.

[0224] "A design system for eyeglass lenses, comprising a design section, wherein..."

[0225] When the aberration distribution of the eye and at least one of the eyeglass lenses varies greatly due to the wearer's physical characteristics, the design solution is to obtain an eyeglass lens with weak non-rotational symmetry in the aberration distribution within a specified width region centered on each point on the principal meridian of the eyeglass lens.

[0226] When the degree of change is small, the spectacle lens with strong non-rotational symmetry in the region is obtained as the design solution.

[0227] One embodiment of the spectacle lens design system of the present invention only requires the aforementioned design unit. This design unit can be mounted on a computer that runs a prescribed program as needed.

[0228] In one embodiment of the present invention, the eyeglass lens design system preferably has the following structure in addition to the design section described above.

[0229] • Calculation unit for Di, Li, etc.

[0230] • A storage unit that stores multiple design solutions with different Li values ​​(including Li values, basic design, design data, etc.), the wearer's Di, Ei and Ei' used to obtain Di, and reference value Ds, etc.

[0231] • Eye measuring device for obtaining Di

[0232] • A spectacle lens measuring device for obtaining Li

[0233] • The decision section for determining whether Di > Ds or Di ≦ Ds

[0234] Figure 4 This is a structural block diagram illustrating a design system for eyeglass lenses according to one embodiment of the present invention.

[0235] The computing unit is capable of calculating equations 1 to 4 above. A component within the computer that runs prescribed programs as needed can perform the functions of the computing unit.

[0236] The storage unit can store at least one of the following: design solutions for multiple lenses; statistically or academically obtained standard or average aberrations related to the wearer's eyeball (excluding Di and Ds); the wearer's eyeball rotation; the wearer's pupillary diameter variation; the wearer's age; the environment or purpose in which the wearer uses the glasses; and the time elapsed since the wearer's last visit to the optical shop. The storage unit can be an HDD or similar device mounted on a computer.

[0237] There are no restrictions on the eyeball measuring device as long as it can collect information for obtaining Di. Similarly, there are no restrictions on the spectacle lens measuring device as long as it can collect information for obtaining Li. For example, the Fujinon F601 manufactured by Fujifilm Corporation, a small laser interferometer using the Fizeau interferometry method, can be used to obtain wavefront data and aberration distribution.

[0238] This system may not always include a computing unit, a storage unit, an ocular measuring device, and / or a spectacle lens measuring device. For example, the aforementioned units located on the Internet outside this system can be connected to this system.

[0239] The following describes each process of using this system.

[0240] Figure 5 This is a flowchart of a spectacle lens design system according to one embodiment of the present invention.

[0241] First, the aberrations at each m and n on polar coordinates representing the Zernike aberration coefficients in the subject (the wearer behind) are obtained using an ophthalmometer (ophthalmometer measurement procedure). At this point, the aberrations before and after blinking are obtained. Based on these results, Ei (the aberration of the eye before blinking) and Ei' (the aberration of the eye after blinking) are calculated by the calculation unit (Ei calculation procedure, Ei' calculation procedure). Based on these results, Di is calculated (Di calculation procedure). This Di is then stored in the storage unit (Di storage procedure). Alternatively, Ei and Ei' can also be stored in the storage unit.

[0242] It is worth noting that, in one embodiment of the present invention, each of the pre-prepared lens design solutions 1 to n (n being an integer of 2 or more) Li1 to n (Li preparation process) is obtained in advance. Li1 to n are stored in the storage unit.

[0243] Multiple lens design solutions can be prepared in advance to replace the Li preparation process. The aberration quantities at each m and n on the polar coordinates representing the Zernike aberration coefficients in the lens are obtained using a spectacle lens measuring instrument (spectacle lens measuring process). It is worth noting that, for ease of explanation, the lens design solution before actual spectacle lens manufacturing is referred to as the "spectacle lens measuring process." Of course, physical spectacle lenses can be prepared in advance, and the aberration quantities at each m and n on the polar coordinates representing the Zernike aberration coefficients in the lens are obtained using a spectacle lens measuring instrument. Based on the results of the above spectacle lens measuring process, Li is calculated by the calculation unit (Li calculation process). This Li is stored in the storage unit (Li storage process).

[0244] The reference value Ds is calculated by the calculation unit based on the data of each wearer stored in the storage unit (Ds calculation process). This Ds is then stored in the storage unit (Ds storage process).

[0245] Then, the determination unit determines whether Di > Ds or Di ≦ Ds. If Di > Ds, the design unit selects the design solution for the lens with the lower value from each of Li1 to n (design process). At this time, a design solution can be selected from each of Li1 to n, which are multiple lens design solutions, based on the magnitude of the difference between Di and Ds. For example, if Di > Ds and the difference between Di and Ds is extremely large, the design solution with the lowest value can be selected from each of Li1 to n.

[0246] Furthermore, as a variation of an embodiment of the present invention, the reference value Ls can be calculated by the calculation unit using the described method (Ls calculation process). This Ls can be stored in the storage unit (Ls storage process). Moreover, in the design process, the level of Li relative to the reference value Ls can be evaluated, and a predetermined value of Li can be selected.

Claims

1. A design method of eyeglass lenses, wherein, when an index quantifying the degree of change in the aberration distribution of at least one of the eye and the eyeglass lenses being worn due to the physical characteristics of the wearer is Di, a reference value of Di is Ds, an index quantifying the non-rotationally symmetric property in the aberration distribution of the eyeglass lenses is Li, a reference value of Li is Ls, an index quantifying the non-rotationally symmetric property related to the aberration distribution of the eye and being an index before the wearer blinks is Ei, and an index quantifying the non-rotationally symmetric property related to the aberration distribution of the eye and being an index after the wearer blinks is Ei', Di is at least an index quantifying the non-rotationally symmetric property in the aberration distribution of the cornea of the eye of the wearer around the optical axis, and the index is an index represented by the following formula 1, Li is an index represented by the following formula 2, E and E' represent polar coordinates of Zernike aberration coefficients of the eye of the wearer, L represents polar coordinates of Zernike aberration coefficients of the eyeglass lenses, E is related to the shape of the tear layer on the corneal surface before the wearer blinks, E' is related to the shape of the tear layer on the corneal surface after the wearer blinks, m is a value representing the number of times in the circumferential direction, and n is a value representing the number of times in the radial direction, in a case where the degree of change in the aberration distribution of the eye due to the change in the shape of the tear layer on the corneal surface accompanying the blinking of the wearer is large, that is, Di is larger than Ds, an eyeglass lens in which the non-rotationally symmetric property of the aberration distribution in a region in a prescribed width range centered on each point on the principal meridian of the eyeglass lenses is weak, that is, Li is lower than Ls, is obtained as a design solution, in a case where the degree of change in the aberration distribution of the eye due to the change in the shape of the tear layer on the corneal surface accompanying the blinking of the wearer is small, that is, Di is Ds or less, an eyeglass lens in which the non-rotationally symmetric property in the region is strong, that is, Li is higher than Ls, is obtained as a design solution.

2. The design method of eyeglass lenses according to claim 1, wherein, the physical characteristics of the wearer refer to at least one of the degree of left-right asymmetry in the shape of the nose when viewed from the front, the difference in height of the positions of the eyeglass frames on the left and right ears, and the shape stability of the tear layer of the wearer.

3. The design method of eyeglass lenses according to claim 1, wherein, the obtaining of the eyeglass lenses as design solutions includes selecting one from a plurality of design solutions in which Li is different.

4. The design method of eyeglass lenses according to claim 1, wherein, Ds is determined on the basis of at least one of a standard or average aberration related to the eyeball of the eyeglass wearer, the degree of eye rotation of the wearer, the degree of change in the pupil diameter of the wearer, the age of the wearer, the environment or use of the eyeglasses used by the wearer, and the time elapsed since the wearer last visited the eyeglass store, which are obtained statistically or academically.

5. The design method of eyeglass lenses according to claim 1, wherein, the eyeglass lenses are obtained as design solutions according to the magnitude of the difference between Di and Ds.

6. The design method of eyeglass lenses according to claim 1, wherein, ​ The spectacle lens is a progressive power lens.

7. A manufacturing method of a spectacle lens, which manufactures a spectacle lens designed by the design method of any one of claims 1 to 6.

8. A design system of a spectacle lens, which comprises a design section, In the design section, when an index quantifying the degree of change in the aberration distribution of at least one of the eye and the spectacle lens in wear due to the physical characteristics of the wearer is Di, a reference value of Di is Ds, an index quantifying the non-rotationally symmetric property in the aberration distribution of the spectacle lens is Li, a reference value of Li is Ls, an index quantifying the non-rotationally symmetric property related to the aberration distribution of the eye and being an index before the blinking of the wearer is Ei, and an index quantifying the non-rotationally symmetric property related to the aberration distribution of the eye and being an index after the blinking of the wearer is Ei', Di is at least an index quantifying the non-rotationally symmetric property in the aberration distribution of the cornea of the eye of the wearer around the optical axis, and the index is an index represented by the following formula 1, Li is an index represented by the following formula 2, E and E' represent polar coordinates of Zernike aberration coefficients of the eye of the wearer, L represents polar coordinates of Zernike aberration coefficients of the spectacle lens, E is related to the shape of the tear layer of the corneal surface before the blinking of the wearer, E' is related to the shape of the tear layer of the corneal surface after the blinking of the wearer, m is a value representing the number of times in the circumferential direction, and n is a value representing the number of times in the radial direction, in a case where the degree of change in the aberration distribution of the eye due to the change in the shape of the tear layer of the corneal surface accompanying the blinking of the wearer is large, that is, Di is larger than Ds, a spectacle lens in which the non-rotationally symmetric property of the aberration distribution in a region in a prescribed width range centered on each point on the principal meridian of the spectacle lens is weak, that is, Li is lower than Ls, is obtained as a design solution, in a case where the degree of change in the aberration distribution of the eye due to the change in the shape of the tear layer of the corneal surface accompanying the blinking of the wearer is small, that is, Di is Ds or less, a spectacle lens in which the non-rotationally symmetric property in the region is strong, that is, Li is higher than Ls, is obtained as a design solution.

9. The design system of a spectacle lens according to claim 8, wherein the physical characteristics of the wearer refer to at least one of the degree of left-right asymmetry in the shape of the nose when viewed from the front, the difference in height of the positions of the eyeglasses frames on the left and right ears, and the shape stability of the tear layer of the wearer.

10. The design system of a spectacle lens according to claim 8, wherein the acquisition of the spectacle lens as a design solution includes the selection of one from a plurality of design solutions in which Li is different.

11. The design system of a spectacle lens according to claim 8, wherein Ds is determined on the basis of at least one of a standard or average aberration of the eyeball of the wearer of the eyeglasses, the degree of cyclotorsion of the wearer, the degree of change in the pupil diameter of the wearer, the age of the wearer, the environment or use of the eyeglasses by the wearer, and the time elapsed since the last visit of the wearer to the optician.

12. The eyeglass lens design system of claim 8, wherein, the eyeglass lens is obtained as a design solution according to the difference between Di and Ds.

13. The eyeglass lens design system of claim 8, wherein, the eyeglass lens is a progressive power lens.

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