Eyeglass lenses, design method and system

Abstract

To provide myopia progression suppression technology designed to cope with the RPR of the wearer.SOLUTION: Provided are a spectacle lens, and related technology thereto, comprising a base region where a beam incident from an object-side surface is emitted from an eyeball-side surface and converged on a retina via an eyeball, and a plurality of defocus regions in contact with the base region and where a beam passing through at least some of the defocus regions enters the retina as divergent light. In more than half of the plurality of defocus regions, the defocus power and / or size of each defocus region is set so as to compensate for a change of spot size on the retina due to relative peripheral refraction (RPR) that corresponds to the eccentric angle of the eyeball of a wearer.SELECTED DRAWING: Figure 9

Description

[Technical Field]

[0001] The present invention relates to a spectacle lens, a design method therefor, and a design system therefor. [Background technology]

[0002] Spectacle lenses that suppress the progression of refractive errors such as myopia include those that have island-shaped regions formed on the lens, each with a refractive power that is more positive than the prescribed refractive power (see, for example, Patent Document 1). Spectacle lenses of the type described in Patent Document 1 are also called DIMS (Defocus Incorporated Multiple Segments) spectacle lenses, or DIMS for short. Hereinafter, these island-shaped regions will be referred to as defocus regions.

[0003] With spectacle lenses of this configuration, the light beam that enters from the surface on the object side and exits from the surface on the eyeball side will, in principle, be focused on the wearer's retina, but the light beam that passes through the defocus area will be focused at a position closer to the retina, thereby suppressing the progression of myopia.

[0004] In this specification, the forward direction in the optical axis direction in which the object to be viewed is located is referred to as the near side, and the opposite direction of the near side, that is, the rear direction in the optical axis direction, i.e., the depth direction from the eyeglass lens toward the eyeball, is referred to as the far side. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] U.S. Patent Application Publication No. 2017 / 0131567 Summary of the Invention [Problem to be solved by the invention]

[0006] FIG. 1 is a diagram showing how light rays entering the eye from the peripheral visual field are focused behind the peripheral retina when the DIMS described in FIG. 1 of Patent Document 1 is worn.

[0007] As shown in Figure 1, light rays entering the eye from the peripheral field of view, corresponding to the eccentricity angle from the optical axis, pass through the spectacle lens at an angle, resulting in off-axis astigmatism (oblique astigmatism) and off-axis hyperopia.

[0008] As a result, a misalignment occurs between the optical focal plane (base power image position locus) and the peripheral retina, as shown in Figure 1. Due to this misalignment, the actual defocus power may be lower than the defocus power set in DIMS.

[0009] This misalignment usually increases the further away from the fovea of ​​the retina. The refractive power that causes this misalignment is also called relative peripheral refraction (RPR). A detailed definition will be given later.

[0010] The inventors believe that when wearing DIMS, the shape and size of the spot (light spot; in other words, the spread of the light beam that causes the light spot) formed on the retina by the parallel light beam that enters the defocus area is a key factor in the effectiveness of suppressing the progression of myopia.

[0011] An object of one embodiment of the present invention is to provide a myopia progression suppression technique that corresponds to the RPR of the wearer. Another embodiment of the present invention aims to evaluate existing designs using a wearer's RPR and select lenses that are more effective in suppressing the progression of myopia. [Means for solving the problem]

[0012] A first aspect of the present invention is a base region that causes a light beam incident from the object-side surface to exit from the eyeball-side surface and converge on the retina via the eyeball; a plurality of defocus regions in contact with the base region, the defocus regions having a property that a light beam passing through at least a part of the defocus regions is incident on a retina as divergent light; Equipped with In at least half of the plurality of defocus areas, at least one of the defocus power and the size of each defocus area is set so as to compensate for a change in spot size on the retina due to a relative peripheral refraction (RPR) according to the decentration angle of the wearer's eyeball.

[0013] A second aspect of the present invention is the first aspect of the present invention, In 80% or more of the plurality of defocus regions, The size of each defocus area is equal, and the defocus power of each defocus area is set so as to compensate for the change in spot size on the retina due to the RPR.

[0014] A third aspect of the present invention is the first aspect, In 80% or more of the plurality of defocus regions, The size of each defocus area is set so that the defocus power of each defocus area is equal and so as to compensate for the change in spot size on the retina due to the RPR.

[0015] A fourth aspect of the present invention is the aspect according to any one of the first to third aspects, At least 80% of the plurality of defocus areas have a toric shape that cancels out the astigmatism component caused by the RPR according to the decentration angle corresponding to the position of each defocus area.

[0016] A fifth aspect of the present invention is the fourth aspect, In each toric defocus area, the amount of remaining astigmatism after offsetting the astigmatism component of the RPR is 1 / 3 or less of the actual defocus power in each defocus area after subtracting the equivalent spherical power of the RPR according to the decentering angle corresponding to the position of each defocus area from the defocus power in each defocus area.

[0017] A sixth aspect of the present invention is an aspect according to any one of the first to fifth aspects, In 80% or more of the multiple defocus areas, the actual defocus power in each defocus area after subtracting the equivalent spherical power of the RPR according to the decentering angle corresponding to the position of each defocus area from the defocus power in each defocus area is in the range of 1.0 to 4.5D.

[0018] A seventh aspect of the present invention is an aspect according to any one of the first to sixth aspects, The eyeglass lenses are myopia progression suppression lenses.

[0019] An eighth aspect of the present invention is a base region that causes a light beam incident from the object-side surface to exit from the eyeball-side surface and converge on the retina via the eyeball; a plurality of defocus regions in contact with the base region, the defocus regions having a property that a light beam passing through at least a part of the defocus regions is incident on a retina as divergent light; A method for designing eyeglass lenses, comprising: The method for designing a spectacle lens includes a setting step of setting at least one of the defocus power and the size of each defocus area so as to compensate for a change in spot size on the retina caused by a relative peripheral refraction (RPR) according to an eccentricity angle of the wearer's eyeball in at least half of the plurality of defocus areas.

[0020] A ninth aspect of the present invention is the eighth aspect of the present invention, The spot size is obtained based on retinal shape data constructed from data on a plurality of RPRs corresponding to mutually different eccentric angles and data on the axial length of the wearer's eye.

[0021] A tenth aspect of the present invention is the eighth or ninth aspect of the present invention, a position conversion step of calculating a position on the eyeglass lens corresponding to the decentering angle, or calculating the decentering angle corresponding to the position on the eyeglass lens; the setting step of setting at least one of the defocus power and the size of each defocus area so as to compensate for a change in spot size on the retina due to the RPR at the decentration angle corresponding to the position; and In the position conversion process, an area having the optical center on the spectacle lens as its center and a radius of one value within a range of 2 to 6 mm is defined as a rotation coverage range, and the decentering angle corresponding to a position within this range is set to zero. Regarding the decentering angle corresponding to a predetermined position on the spectacle lens outside the rotation coverage range, the eyeball is rotated so that the line of sight passes through a point on the boundary line of the rotation coverage range that is on a line formed by the predetermined position and the optical center on the spectacle lens, and the decentering angle is then set to the angle formed by the optical axis of the eyeball and a line connecting the predetermined position and the entrance pupil of the eyeball.

[0022] An eleventh aspect of the present invention is a method for manufacturing a semiconductor device comprising: a base region that causes a light beam incident from the object-side surface to exit from the eyeball-side surface and converge on the retina via the eyeball; a plurality of defocus regions in contact with the base region, the defocus regions having a property that a light beam passing through at least a part of the defocus regions is incident on a retina as divergent light; A spectacle lens design system comprising: Selecting an individual design mode in which at least one of the defocus power and the size of each defocus area is set so as to compensate for a change in spot size on the retina due to a relative peripheral refraction (RPR) according to the decentration angle of the wearer's eyeball in at least half of the plurality of defocus areas, or an existing design mode in which one of a plurality of design data prepared in advance including the base region and the plurality of defocus regions, the design data having different patterns of the defocus regions, is adopted; The present invention relates to a spectacle lens design system, and is provided with a first selection unit that selects:

[0023] A twelfth aspect of the present invention is the eleventh aspect of the present invention, In the existing design mode, from the plurality of design data, the design data that minimizes the change in spot size on the retina due to the RPR of the wearer in each defocus region is adopted.

[0024] A thirteenth aspect of the present invention is the eleventh or twelfth aspect of the present invention, The spot size is obtained based on retinal shape data constructed from data on a plurality of RPRs corresponding to mutually different eccentric angles and data on the axial length of the wearer's eye.

[0025] Other aspects of the present invention that can be combined with the above aspects are as follows.

[0026] Approximately circular defocus regions may be arranged in an island pattern (i.e., spaced apart and not adjacent to each other) around the center of the eyeglass lens at equal intervals in the circumferential and radial directions. An example of the arrangement of the defocus regions in a planar view is an arrangement in which the defocus regions are independently and discretely arranged so that the centers of the respective convex regions are at the vertices of an equilateral triangle (the centers of the defocus regions are arranged at the vertices of a honeycomb structure). In this case, the intervals between the defocus regions may be 1.0 to 2.0 mm. The number of defocus regions may be 100 to 100,000.

[0027] Each defocus region is configured, for example, as follows: The diameter of the defocus region is preferably about 0.6 to 2.0 mm The protrusion height (protrusion amount) of the defocus region is preferably about 0.1 to 10 μm, and more preferably about 0.4 to 2.0 μm.

[0028] There is no limitation on the specific value of the defocus power before subtracting the spherical equivalent power of the RPR, but for example, the minimum value of the defocus power caused by the defocus area on the DIMS is preferably in the range of 0.5 to 4.5 D and the maximum value is in the range of 3.0 to 10.0 D. The difference between the maximum and minimum values ​​is preferably in the range of 1.0 to 5.0 D.

[0029] It is preferable that 80% or more of the multiple defocus areas have a toric shape that cancels out the astigmatism component caused by the RPR according to the decentering angle corresponding to the position of each defocus area, and that the long / short axis ratio (radial size / circumferential size) of the spot size for the wearer is made equal (with a fluctuation range within ±10% (preferably within ±5%, and more preferably within ±1%)).

[0030] The following other aspects may be considered as inventions on their own. When the RPR on the nose side of the retina is different from the RPR on the ear side at the same eccentricity angle, it is preferable that the setting patterns of at least one of the defocus power and size for each defocus area be different between the multiple defocus areas arranged on the nose side of the lens and the multiple defocus areas arranged on the ear side of the lens.

[0031] It is preferable that the defocus power of the defocus area increases and / or the size of the defocus area increases from the center to the periphery of the spectacle lens.

[0032] It is preferable that the defocus power setting patterns for the plurality of defocus areas arranged on the nose side and the plurality of defocus areas arranged on the ear side are different.

[0033] The defocus regions located on the nose side preferably have a higher defocus power and / or a larger size pattern than the defocus regions located on the ear side, and when larger defocus regions are used, the spacing between them should also be increased. [Effects of the Invention]

[0034] According to one embodiment of the present invention, it is possible to provide a myopia progression suppression technique that corresponds to the RPR of the wearer. According to another embodiment of the present invention, the wearer's RPR can be used to evaluate existing designs and select lenses that are more effective at slowing the progression of myopia. [Brief explanation of the drawings]

[0035] [Figure 1] FIG. 1 is a diagram showing how light rays entering the eye from the peripheral visual field are focused behind the peripheral retina when the DIMS described in FIG. 1 of Patent Document 1 is worn. [Figure 2] FIG. 2 is a diagram showing an outline of how to measure RPR using an autorefractometer (eye refraction / corneal curvature radius measuring device). [Figure 3] FIG. 3 is a diagram illustrating a ray tracing method for determining a spot on the retina. [Figure 4] FIG. 4 is a graph showing the relationship between RPR on the horizontal meridian and eccentricity angle in one subject (i.e., case). [Figure 5] FIG. 5 is a diagram showing an outline of calculation of a position on a spectacle lens corresponding to an eccentricity angle based on the eccentricity angle of the wearer's eyeball. [Figure 6] FIG. 6 is a graph showing the relationship between the RPR and the horizontal cross-sectional position on the spectacle lens corresponding to each decentration angle for one subject according to FIG. [Figure 7] FIG. 7 is a diagram showing an outline of the shape of a spot when the shape of the defocus region is a toric shape (cylinder shape) in one embodiment of the present invention. [Figure 8] FIG. 8 is a graph showing the relationship between the power of the defocus area designed to correspond to the case of FIG. 4 and the horizontal cross-sectional position on the spectacle lens. [Figure 9]Fig. 9 is a schematic plan view of a spectacle lens corresponding to the case shown in Fig. 4, in which the defocus areas are independently and discretely arranged so that the centers of the defocus areas of the spherical shape design form an equilateral triangular array distribution. Darker colors indicate greater defocus power. [Figure 10] Fig. 10 is a schematic plan view of a spectacle lens corresponding to the case of Fig. 4, in which each defocus area of ​​Fig. 9 has been changed to a toric shape design in which the major axis is in the radial direction (tangential direction) and the minor axis is in the circumferential direction (sagittal direction). The darker the color, the greater the defocus power. [Figure 11] Fig. 11 is a schematic plan view of a spectacle lens in which each defocus region in Fig. 9 has been modified so that the defocus power of each defocus region is equal while the size of each defocus region is set to correspond to the case of Fig. 4. The darker the color, the larger the size of the defocus region. [Figure 12] Fig. 12 is a schematic plan view of a spectacle lens corresponding to the case of Fig. 4, in which each defocus area of ​​Fig. 11 has been changed to a toric shape design in which the major axis is in the radial direction (tangential direction) and the minor axis is in the circumferential direction (sagittal direction). The darker the color, the larger the size of the defocus area. [Figure 13] Figure 13 shows the distribution of spot sizes on the retina ((b) in the figure) when the defocus power and size of each defocus area are the same ((a) in the figure). Darker colors indicate smaller spots. [Figure 14] 14 shows the distribution of spot sizes on the retina ((c) in the figure) when the size of each defocus area is set to be equal while the defocus power of each defocus area is set ((a) in the figure, approximately the same as FIG. 9), or when the size of each defocus area is set to be equal while the defocus power of each defocus area is set ((b) in the figure, approximately the same as FIG. 11). Darker colors indicate greater defocus power. [Figure 15]Fig. 15 shows the distribution of spot sizes on the retina ((c) in the figure) when each defocus region in Fig. 9 is changed to a toric shape design in plan view with the major axis in the radial direction (tangential direction) and the minor axis in the circumferential direction (sagittal direction) ((a) in the figure, approximately the same as Fig. 10), or when each defocus region in Fig. 11 is changed to a toric shape design in plan view with the major axis in the radial direction (tangential direction) and the minor axis in the circumferential direction (sagittal direction) ((b) in the figure, approximately the same as Fig. 12). Darker colors indicate greater defocus power. [Figure 16] FIG. 16 is a schematic diagram showing an example of the configuration of a spectacle lens supply system according to one aspect of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0036] Hereinafter, embodiments of the present invention will be described. The following explanation based on the drawings is an example, and the present invention is not limited to the exemplified embodiments. Contents not described in this specification are assumed to be fully described in Patent Document 1. Contents not described in Patent Document 1 (particularly content relating to the manufacturing method) are assumed to be fully described in WO2020 / 004551. If there is a discrepancy between the contents of Patent Document 1 and the contents of the publication, the contents of the publication shall take precedence.

[0037] The spectacle lenses (DIMS) mentioned in this specification have an object-side surface and an eyeball-side surface. The "object-side surface" is the surface that is located on the object side when a wearer wears spectacles equipped with the spectacle lenses, and the "eyeball-side surface" is the opposite, i.e., the surface that is located on the eyeball side when a wearer wears spectacles equipped with the spectacle lenses. This relationship also applies to the lens substrate that forms the basis of the spectacle lenses. In other words, the lens substrate also has an object-side surface and an eyeball-side surface.

[0038] In this specification, "to" indicates a value greater than or equal to a predetermined value and less than or equal to a predetermined value.

[0039] <Eyeglass lenses> The spectacle lens (DIMS) according to one embodiment of the present invention is as follows. "A base region that causes the light beam incident from the object side surface to exit from the eyeball side surface and converge on the retina through the eyeball, a plurality of defocus regions in contact with the base region, the defocus regions having a property that a light beam passing through at least a part of the defocus regions is incident on a retina as divergent light; Equipped with A spectacle lens in which at least one of the defocus power and size of each defocus area is set so as to compensate for changes in spot size on the retina due to relative peripheral refraction (RPR) according to the decentration angle of the wearer's eyeball in at least half of the plurality of defocus areas.

[0040] The base region is a portion having a shape that can realize the prescribed refractive power of the wearer, and corresponds to the first refractive region of Patent Document 1.

[0041] A defocus region is a region in which at least a portion does not focus light at the light-focusing position of the base region. A defocus region is a portion corresponding to the micro-convex portion in Patent Document 1. A spectacle lens according to an aspect of the present invention is a myopia progression inhibiting lens, similar to the spectacle lens described in Patent Document 1. Similar to the micro-convex portion in Patent Document 1, the multiple defocus regions according to an aspect of the present invention may be formed on at least one of the object-side surface and the eyeball-side surface of the spectacle lens. This specification mainly illustrates a case in which multiple defocus regions are provided only on the object-side surface of the spectacle lens.

[0042] A defocus region may be formed in the center of the eyeglass lens as shown in Figure 10 of Patent Document 1, or a defocus region may not be formed in the center of the eyeglass lens as shown in Figure 1 of Patent Document 1. In one aspect of the present invention, a case where a defocus region is not formed in the center of the eyeglass lens will be exemplified.

[0043] The "center of the eyeglass lens" refers to the geometric center, optical center, or centering center of the eyeglass lens and its vicinity. In this specification, the centering center and its vicinity are exemplified. The centering center is also referred to as the lens center. In this specification, the center passing through the lens center when the wearer looks straight ahead is exemplified.

[0044] FIG. 1 is a diagram showing how light rays entering the eye from the peripheral visual field are focused behind the peripheral retina when the DIMS described in FIG. 1 of Patent Document 1 is worn. Figure 2 shows an overview of how RPR is measured using an autorefractometer (eye refraction / corneal curvature radius measurement device). CVD indicates the corneal vertex distance. R indicates the center of rotation of the eyeball. α indicates the angle of decentration. P indicates the center of the entrance pupil of the eyeball. Point A indicates the point at which a light ray reaching point A' (the fovea) passes on the surface of the spectacle lens facing the eyeball. Point B indicates the point at which a light ray reaching point B' (the peripheral retina) passes on the back vertex sphere (a sphere with R as the center and AR as the radius) of the spectacle lens. An autorefractometer is an instrument that shines light from the pupil onto the retina and measures the refractive power of the eye from the light reflected back. Commercially available devices (e.g., Shin-Nippon NVision-K5001 (Ajinomoto Trading Inc.)) can be used.

[0045] In this specification, "RPR" is defined as follows.

[0046] The subject, under accommodative paralysis, is asked to rotate and gaze at each fixation target in a direction other than the front. In this state, the refractive power is measured when a ray of light passes through the subject's eyeball from in front of the subject. The difference between this refractive power and the refractive power when the subject is looking straight ahead (state A' in Figure 1) is taken as the RPR. The angle between the direction of the fixation target that the subject is asked to gaze at and the front direction at this time is called the eccentricity angle. Note that the term "subject" in this specification may be used interchangeably with "wearer" because the term "subject" may be used interchangeably with "wearer" for spectacle lenses in the future.

[0047] The "eccentricity angle" in this specification is the angle formed by a line connecting the optical axis of the eyeball, i.e., point A on the spectacle lens through which the wearer's line of sight passes when looking straight ahead, and point P, which is the center of the entrance pupil of the eyeball, and a line connecting a predetermined position outside the eye that is off the optical axis (and thus point B on the spectacle lens through which the wearer's line of sight passes when viewing an object at that predetermined position), and point P, which is the center of the entrance pupil of the eyeball. In other words, the eccentricity angle is ∠APB (α angle) in Figure 2. As shown in Figure 2, the eccentricity angle indicates the degree of eccentricity from point A' (the fovea) to point B' (the peripheral part of the retina). There is a suitable method for defining the eccentricity angle to facilitate the conversion of the eccentricity angle to a position on the spectacle lens, and this definition method will be described later.

[0048] The curvature of the wavefront formed at position A in front of the cornea by a light beam emitted from point A' on the retina as shown in Figure 2 is the refraction value in front vision. The refraction value includes spherical power, astigmatic power, and astigmatic axis angle. The refraction value at an eccentric angle α is measured from the front of the subject while the subject's eyes are fixed in the direction α under accommodative paralysis. Referring to Figure 2, the refraction value at eccentric angle α (i.e., the refraction value at point B' (peripheral retina)) is the curvature of the wavefront formed at point B in front of the cornea by a light beam equivalently emitted from point B' in the peripheral retina. RPR is defined as the difference between the curvature of the wavefront formed at B and the curvature of the wavefront formed at A.

[0049] The specific method for measuring RPR is not limited. For example, RPR may be measured using an apparatus such as Shin-Nippon NVision-K5001 (Ajinomoto Trading Inc.).

[0050] In one aspect of the present invention, at least one of the defocus power and the size of each defocus region is set so as to compensate for the change in spot size on the retina due to RPR in at least half of the multiple defocus regions. In this specification, the "size of the defocus region" refers to the size in a planar view. In this specification, the "size" refers to the area.

[0051] As shown in Figure 1, when the RPR around the retina is positive, the focal point of the lens's base power is located behind the retina, the focal point of the defocused region is relatively close to the retina, and the spot formed on the retina by diverging light from the focal point of the defocused region becomes smaller.To compensate for this, there are two methods: one is to move the focal point of the defocused region away from the retina, that is, to increase the defocused power, and the other is to enlarge the defocused region.

[0052] For example, if the defocus power is initially set to 3.50 D (unit: diopter) in the DIMS, the defocus power will deteriorate depending on the wearer's RPR. In most cases, the degree of deterioration increases as the eccentricity angle increases.

[0053] Therefore, in the defocus area at a position corresponding to a large eccentricity angle, the defocus power is set to be larger than that in the defocus area at a position corresponding to a small eccentricity angle.In this case, additional defocus power is added to the defocus power set uniformly in the defocus area according to the position corresponding to the specified eccentricity angle so as to eliminate the deterioration of the defocus power caused by RPR.

[0054] The defocus area at a position corresponding to a large decentration angle may be set larger than the defocus area at a position corresponding to a small decentration angle. This allows the spot formed on the retina by diverging light from the focusing position of the defocus area to be larger. As a result, the spot size reduction due to RPR can be compensated for.

[0055] The method of increasing the defocus power and the method of increasing the defocus area may be combined.

[0056] "Defocus power" is the refractive power caused by the shape and / or material of the defocus region, and refers to the difference between the average defocus value at the focal position X corresponding to each defocus region and the focus value at the focal position Y, which is a position where light rays passing through a portion other than each defocus region (base region) converge and is located further back than the multiple focal positions X. In other words, "defocus power" is the difference obtained by subtracting the refractive power of the base region from the average value of the minimum and maximum refractive powers of the defocus region. Therefore, the defocus power is also referred to as "average defocus power." In this specification, a case where the defocus region is a convex region is exemplified.

[0057] In this specification, "refractive power" refers to the average refractive power, which is the average value between the refractive power in direction a where the refractive power is minimum and the refractive power in direction b (perpendicular to direction a) where the refractive power is maximum.

[0058] There is no limitation on the surface shape of the defocus region as long as the defocus region has a defocus power that can eliminate the deterioration of defocus power caused by RPR. The defocus region may have a spherical shape, an aspherical shape, a toric shape, or a mixture of these shapes (for example, the center of each defocus region may be spherical and the outer peripheral portion of the center may be aspherical).

[0059] According to one aspect of the present invention, a myopia progression suppression technique that corresponds to the wearer's RPR can be provided. For example, it is possible to compensate for the change in spot size caused by defocusing at the retinal periphery due to RPR, thereby effectively suppressing eyeball growth and slowing the progression of myopia.

[0060] In this specification, "compensating for changes in spot size on the retina due to RPR" refers to bringing the spot size closer to the state before the change, including returning it to the state before the change, partially returning it from the state after the change to the state before the change even if it does not completely return, and also including a state in which the spot becomes larger than the state before the change. "Compensating for changes in spot size" is also referred to as "offsetting changes in spot size."

[0061] A method for calculating the change in spot size will be described below. FIG. 3 is a diagram illustrating a ray tracing method for determining a spot on the retina.

[0062] The shape (ratio of major and minor axes of an ellipse) and size of the spot on the retina due to the defocus area can be calculated using the following method.

[0063] First, determine the ray that passes through the center of the defocus area and the center of the pupil of the eyeball and finally reaches the retina. Then, trace the rays near that chief ray. Trace the incident rays that pass through the periphery of the defocus area and are parallel to the chief ray, and the locus of the points that reach the retina is the range of the spot.

[0064] Since the defocus region in DIMS is small, there is also a simpler method of paraxial ray tracing.

[0065] When the spectacle lens and eyeball model are rotationally symmetric with respect to the optical axis, the chief ray and the optical axis are contained in the same plane. In this case, paraxial ray tracing can be performed separately in the radial and circumferential directions. The exit angle is calculated using the refraction formula from the height h and incident angle μ of the first surface, which becomes the incident angle of the next surface. The height h of the next surface +1 is calculated using the propagation formula from the height of the front surface and the exit angle. By relaying calculations like this, we arrive at the height on the retina. Once the radial and circumferential heights are known, the spot ellipse on the retina can be determined. The formulas for refraction and propagation are as follows:

number

[0066] where n i and n i ´ is the refractive index of the medium before and after the i-th surface. θ i and θ i ´ is the angle of incidence and the angle of emergence of the chief ray incident on the ith surface. q i is the length of the ray from the i-th surface to the i+1-th surface

[0067] h ti , μ ti and μ ti ´ is the radial height, paraxial incidence angle, and paraxial exit angle of the near ray at the i-th surface. Paraxial radial exit angle μ of the ith surface ti ´ is the paraxial radial incidence angle μ of the (i+1)th surface ti+1 The same as μ ti+1 =μ ti ´. C ti is the radial curvature of the ith surface.

[0068] Similarly, h si , μ si and μ si ´ is the circumferential height, paraxial incident angle, and paraxial exit angle of the near ray at the i-th surface. Paraxial exit angle μ in the circumferential direction of the ith surface si ´ is the paraxial incident angle μ in the circumferential direction of the (i+1)th surface si+1 The same as μ si+1 =μ si ´. C si is the circumferential curvature of the ith surface.

[0069] The first surface is the surface of the defocus region, h t0 =h s0 = 1, μ t0 =μ s0 = 0, and then ray tracing is performed to find the height h t6 and h s6 The ratio of the size of the spot on the retina to the size of the defocused area, h t6 / h t0 , h s6 / h s0 is determined, and the size and shape of the spot on the retina are determined. A concept including at least one of the size and shape of the spot is called "spot size."

[0070] <Preferred Examples and Modified Examples of Eyeglass Lenses> Preferred examples and modifications of the spectacle lens (DIMS) according to one aspect of the present invention will be described below.

[0071] It is preferable to set either or both of the defocus power and size so as to compensate for the change in spot size on the retina due to RPR for 80% or more of the total defocus areas in DIMS. 90% or more is preferable, and 95% or more is even more preferable. Hereinafter, the preferred examples of "80% or more of the total defocus areas" are, as above, 90% or more and 95% or more, in descending order of preference, and repeated description will be omitted.

[0072] The size of each defocus area may be equal in 80% or more of the total number of defocus areas, and the defocus power of each defocus area may be set so as to compensate for the change in spot size on the retina due to the RPR (Specific Example 1). This state is also referred to as "a state in which the size of each defocus area is set to be equal across the board."

[0073] Furthermore, the defocus power of each of the defocus areas may be set equal to that of the other defocus areas in 80% or more of the number of the defocus areas, and the size of each defocus area may be set to compensate for the change in spot size on the retina due to the RPR (Specific Example 2). This state is also referred to as "a state in which the same defocus power is set for each defocus area."

[0074] The refractive power of the central points of 80% or more of the defocus areas in the DIMS may be equal. In this specification, the "center" of a defocus area refers to the center of gravity in a planar view, or the vertex in the case of a small lens. Even in this state, the technical concept of the present invention is realized as long as the change in retinal spot size due to RPR is compensated for in at least some of the defocus areas. It is also possible to set a uniformly equal defocus power for each defocus area in 80% or more of the total defocus areas where the change in retinal spot size has been compensated for.

[0075] In this specification, "equal" or "constant" refers to a fluctuation range within ±10% (preferably within ±5%, more preferably within ±1%). For example, if the defocus power in a given defocus region s is 1.5D, the defocus power in another defocus region t is 1.6D, and the defocus power in yet another defocus region u is 1.7D, the defocus power in defocus region t is 1.6D, and 1 / 10 of that is 0.16D. Both the defocus power in defocus region s and the defocus power in defocus region u are within the range of 1.6D to ±0.16D. Therefore, in this specification, the defocus powers in defocus regions s to u are considered to be equal or constant.

[0076] Preferably, 80% or more of the defocus areas have a toric shape that cancels out the astigmatism component (the difference between the maximum and minimum refractive powers) caused by the RPR according to the decentration angle corresponding to the position of each defocus area. This astigmatism component corrects off-axis aberrations (oblique astigmatism). This correction is also called "cancellation."

[0077] The reason why this is preferable will be described in detail in <Design Method of Eyeglass Lenses>, but as shown in Fig. 7 below, as the RPR increases, the astigmatism component of the RPR increases, and the spot size becomes elliptical. In order to eliminate this elliptical shape and make the spot size closer to a perfect circle again, that is, to make it possible to correct off-axis aberrations, it is preferable to make 80% or more of the multiple defocus areas to have a toric shape.

[0078] In each defocus region of the toric shape, the amount of remaining astigmatism after canceling out the astigmatic component of the RPR is preferably 1 / 3 or less of the actual defocus power in each defocus region.

[0079] By correcting off-axis aberrations to a certain extent (as described in the previous paragraph), the light spots formed on the retina by the defocused areas become almost circular and spread evenly. This provides a comfortable wearing experience and is expected to have a stable effect in inhibiting the progression of myopia.

[0080] The toric shape of each defocus region may be combined with the above specific examples 1 and 2.

[0081] In this specification, the "actual defocus power" refers to the power remaining after subtracting the equivalent spherical power of the RPR (i.e., the average value of the maximum power and the minimum power) according to the decentering angle corresponding to the position of each defocus area from the defocus power in each defocus area.

[0082] In 80% or more of the plurality of defocus areas, the actual defocus power in each defocus area after subtracting the spherical equivalent power of the RPR according to the decentering angle corresponding to the position of each defocus area from the defocus power in each defocus area is preferably in the range of 1.0 to 4.5 D. If the actual defocus power can be secured within this range, a stable effect of suppressing the progression of myopia can be expected.

[0083] There is no limitation on the specific value of the defocus power before subtracting the spherical equivalent power of the RPR, but for example, the minimum value of the defocus power caused by the defocus area on the DIMS is preferably in the range of 0.5 to 4.5 D and the maximum value is in the range of 3.0 to 10.0 D. The difference between the maximum and minimum values ​​is preferably in the range of 1.0 to 5.0 D.

[0084] <Example of eyeglass lenses> The arrangement of the multiple defocus areas is not particularly limited, and can be determined from the viewpoint of, for example, visibility from outside the defocus areas, adding design features to the defocus areas, and adjusting refractive power using the defocus areas.

[0085] As will be described in detail in the <Design Method of Spectacle Lens> section below, as shown in Figures 9 to 12, approximately circular defocus regions may be arranged in an island-like pattern (i.e., spaced apart and not adjacent to each other) at equal intervals in the circumferential and radial directions around the center of the spectacle lens. One example of the arrangement of defocus regions in a planar view is an independent, discrete arrangement where the centers of the convex regions are at the vertices of an equilateral triangle (the centers of the defocus regions are arranged at the vertices of a honeycomb structure). In this case, the interval between the defocus regions may be 1.0 to 2.0 mm. The number of defocus regions may be 100 to 100,000.

[0086] However, one aspect of the present invention is not limited to the content described in Patent Document 1. In other words, the defocus regions are not limited to being spaced apart and not adjacent to each other, and may be in contact with each other or may be arranged non-independently like a chain of beads.

[0087] Each defocus region is configured, for example, as follows: The diameter of the defocus region is preferably about 0.6 to 2.0 mm The protrusion height (protrusion amount) of the defocus region is preferably about 0.1 to 10 μm, and more preferably about 0.4 to 2.0 μm.

[0088] <Design method for eyeglass lenses> The present invention can also be applied to a design method for eyeglass lenses (DIMS). Specifically, the method includes a setting step of setting at least one of the defocus power and size of each defocus area so as to compensate for changes in spot size on the retina due to RPR according to the decentration angle of the wearer's eyeball in more than half of the multiple defocus areas. Details of each component of this design method will be omitted as they overlap with the description of <Eyeglass Lenses>. The content described below mainly focuses on content not included in <Eyeglass Lenses>. The technical concept of the present invention is also reflected in the method of manufacturing eyeglass lenses designed using this design method.

[0089] (Designing eyeglass lenses based on the wearer's case history) 4 is a graph showing the relationship between RPR and the decentration angle of the wearer's eyeball, which is the decentration angle on the horizontal meridian passing through the line of sight of the spectacle lens in frontal vision (i.e., case) for one subject. SE is the average value of the radial and circumferential refractive powers, i.e., the mean refractive power.

[0090] The "predetermined eccentricity angle on the horizontal meridian" is the angle between the frontal gaze direction and the direction of the fixation target on the horizontal meridian. In one embodiment of the present invention, the fixation targets are set at 10 degrees (10N), 20 degrees (20N), and 30 degrees (30N) on the nasal side. Also, the fixation targets are set at 10 degrees (10T), 20 degrees (20T), and 30 degrees (30T) on the temporal side.

[0091] At the same decentration angle (for example, 20N and 20T), the RPR of the nose-side portion of the peripheral retina is often greater than the RPR of the ear-side portion, as shown in Figure 4. The defocus area located on the ear side of the spectacle lens acts on the peripheral retina close to the nose side. Therefore, it is desirable to design the defocus power imparted to the ear-side defocus area of ​​the spectacle lens and / or the size of the defocus area so that it is greater than the size of the defocus area located on the nose side of the spectacle lens at the same distance from the center of the spectacle lens.

[0092] Of course, there are cases where the RPR of the nasal part of the peripheral retina is smaller than the RPR of the temporal part, contrary to Figure 4. A suitable example that can also handle this case is as follows. "When the RPR on the nasal side of the retina differs from the RPR on the temporal side at the same eccentricity angle, the setting patterns of at least one of the defocus power and size for each defocus area are different between the multiple defocus areas arranged on the nasal side of the lens and the multiple defocus areas arranged on the temporal side of the lens."

[0093] At the same decentration angle (for example, 20N and 20T), if the RPR on the nose side of the peripheral retina is higher than the RPR on the ear side, it is preferable to set the multiple defocus areas located on the ear side of the spectacle lens to a higher defocus power and / or to set the defocus areas to be larger than the multiple defocus areas located on the nose side of the spectacle lens.

[0094] Generally, the larger the decentering angle, the larger the RPR value. Therefore, it is preferable that the defocus power of the defocus area is greater and / or the defocus area is larger from the center to the periphery of the spectacle lens.

[0095] On the other hand, there are cases where the RPR value decreases as the decentering angle increases. In this case, it is preferable that the defocus power and / or the defocus area be smaller from the center to the periphery of the spectacle lens.

[0096] In some cases, the RPR value increases initially and then decreases as the decentering angle increases. In this case, it is preferable to set the defocus power of the defocus area to increase and then decrease, or to increase and then decrease, from the center to the periphery of the spectacle lens.

[0097] In some cases, the RPR value decreases once and then increases as the decentering angle increases. In this case, it is preferable to set the defocus power of the defocus area to decrease and then increase, or to decrease and then increase, from the center to the periphery of the spectacle lens.

[0098] The configurations in which the above cases are reflected in eyeglass lenses are as follows. The defocus power setting pattern for each of the multiple defocus areas arranged on the nose side is different from that for the multiple defocus areas arranged on the ear side. The multiple defocus areas arranged on the nose side have a higher defocus power and / or a larger setting pattern than the multiple defocus areas arranged on the ear side. The defocus power of each defocus area increases and / or the defocus area increases from the center to the periphery of the spectacle lens. The defocus power of each defocus area decreases and / or the size of each defocus area decreases from the center to the periphery of the spectacle lens. From the center to the periphery of the eyeglass lens, the defocus power of each defocus area increases and then decreases, or increases and then decreases, or the defocus power of each defocus area decreases and then increases, or decreases and then increases, as the lens moves from the center to the periphery.

[0099] There is no limitation on the specific numerical values ​​of the defocus power and size of the defocus region, and there is no limitation on the number of defocus regions. Furthermore, the defocus power and / or size of the defocus region may change continuously or discontinuously (in steps) as the position on the spectacle lens moves from the center to the periphery.

[0100] (Position conversion process for calculating the position on the eyeglass lens corresponding to the decentering angle) When the eye is facing forward, the position of the spectacle lens according to the decentering angle is the point where a straight line extending from the entrance pupil position of the eye and forming the decentering angle with the optical axis intersects with the spectacle lens. However, considering that the eyeball is constantly rotating, this method of determining the correspondence between the decentering angle and the position on the spectacle lens is not necessarily the best method. 5 is a diagram showing an outline of calculation of a position on the spectacle lens corresponding to the decentration angle based on the decentration angle of the wearer's eyeball. Point E indicates the point at which a ray of light reaching point A' (the fovea) passes through the object-side surface of the spectacle lens. Point F indicates the point at which a ray of light reaching point B' (the peripheral part of the retina) passes through the object-side surface of the spectacle lens.

[0101] The eye always rotates to see objects. Therefore, positions on the spectacle lens do not correspond one-to-one to specific positions on the retina. Hereinafter, this one-to-one correspondence will also be referred to as link. If the two positions are not linked, it is difficult to calculate the position on the spectacle lens that corresponds to the decentration angle. If it is difficult to calculate this position, it ultimately becomes difficult to determine at which position on the spectacle lens the defocus area should be located, and also to determine the level of defocus power and size of the defocus area.

[0102] Therefore, we assume that the eyeball always rotates in the range in the center of the lens, including the front line of sight, and that it is linked to the fovea on the retina. This range is called the rotation coverage range. An example is shown in Figure 5.

[0103] A specific range of rotation angle on the lens from 0 degrees to 10 degrees (Max rotation angle (10 degrees), Covered by rotation in Figure 5) is defined as the rotation coverage range, and is assumed to be linked to the foveal position on the retina (Figure 5). Positions outside the rotation coverage range on the lens are linked to the peripheral part of the retina at a specific eccentricity angle. Figure 5 also shows the relationship between the position on the lens and the eccentricity angle at that time. Point E, on the boundary line of the rotation coverage range, is located on the line formed by point F on the lens and the front line of sight passing point O. When the eyeball is rotated so that point E becomes the line of sight passing point, the ray passing through point F and the entrance pupil P is traced. ∠APB, or α, is the eccentricity angle, and is linked to point B' on the retina.

[0104] The link relationship between the position on the lens and the position on the retina determined in this way is not always maintained, but even if it does deviate, the resulting error in defocus power is limited.

[0105] The above content is summarized as follows: "In the position conversion process, a region having a center at the line of sight passing through on the spectacle lens in front view and a radius of one value within a range of 2 to 6 mm is defined as a rotation coverage range, and the decentering angle corresponding to a position within this range is set to zero, and the decentering angle corresponding to a predetermined position on the spectacle lens outside the rotation coverage range is set to the angle formed by the line connecting the predetermined position and the entrance pupil of the eyeball and the optical axis of the eyeball after rotating the eyeball so that the line of sight passes through a point on the boundary line of the rotation coverage range that is on the line formed by the predetermined position and the line of sight passing through on the spectacle lens in front view."

[0106] For example, if the rotation coverage range is 10 degrees or less from the front direction, the radius of the rotation range of the eye on the spectacle lens is the distance from the center of rotation to the lens (approximately 27 mm) x tan 10 degrees, or approximately 4.8 mm. It is assumed that the range within a circle with a radius of 4.8 mm from the center of the lens is covered by rotation of the eye and linked to the fovea.

[0107] Any position on the spectacle lens other than the 4.8mm radius will be linked to the retinal point of the light ray that passes through the pupil and passes through that position when the eyeball is rotated to a position 4.8mm on the meridian connecting the center of the lens to that position. Figure 5 shows the relationship between the position on the lens and the decentration angle in this example. An example of this relationship is shown in the table below. [Table 1]

[0108] The calculation conditions for this relationship are: the distance from the lens surface to the center of rotation CR = 27 mm; the distance from the eye's entrance pupil position P to the center of rotation PR = 12 mm; and the rotation cover angle (radius) is 10 degrees. Using this method, the RPR measurement point (position on the retinal periphery) and, in turn, the position on the spectacle lens obtained from the decentration angle can be determined at least on the horizontal meridian that passes through the lens center. Using the above method, the graph in Figure 4 can be converted into Figure 6.

[0109] FIG. 6 is a graph showing the relationship between the RPR and the horizontal cross-sectional position on the spectacle lens corresponding to each decentration angle for one subject according to FIG.

[0110] In the position conversion step, a decentering angle corresponding to a predetermined position on the spectacle lens may be calculated, or a position on the spectacle lens corresponding to a predetermined decentering angle may be calculated. In either case, it is sufficient that at least one of the defocus power and the size of each defocus area is set so as to compensate for a change in spot size on the retina due to the RPR at the decentering angle corresponding to the position in the setting step.

[0111] (Expansion of RPR data on the horizontal meridian to other than the horizontal meridian) When only RPR data on the horizontal meridian is available, the RPR on a radial line other than the horizontal meridian may be estimated from the RPR on the nasal side and the RPR on the temporal side on the horizontal meridian at the same eccentricity angle, for example, using the following formula:

number

[0112] Here, P(φ) is the value of RPR at azimuth angle φ, where φ=0° is the nasal side and φ=180° is the temporal side.

[0113] The position on the spectacle lens on the horizontal meridian obtained by conversion from the decentration angle using the above formula may be expanded to a position other than the horizontal meridian.

[0114] If the distribution of RPR with respect to positions on the eyeglass lens is obtained, it becomes possible to set the defocus power and size of multiple defocus regions so as to form light spots of uniform shape and size on the retina, for example.

[0115] In many cases, the axis of astigmatism in RPR is close to 0 degrees or 90 degrees, so the refractive powers of both principal meridians can be considered as radial and circumferential powers.

[0116] FIG. 6 is a graph showing the relationship between the RPR and the horizontal cross-sectional position on the spectacle lens corresponding to each decentration angle for one subject according to FIG.

[0117] By converting each decentering angle into a position on the spectacle lens using the method described above, the RPR curve on the cross section of the lens center (= geometric center) can be obtained (Figure 6).

[0118] As explained with reference to Fig. 4, it is the defocus area located on the ear side of the spectacle lens that acts on the peripheral part of the retina close to the nose side. Therefore, it is desirable to design the defocus power imparted to the defocus area on the ear side of the spectacle lens and / or the size of the defocus area so that it is larger than the defocus area located at the same distance from the center of the spectacle lens and on the nose side of the spectacle lens.

[0119] For example, if the size of the defocus area is uniform and the actual defocus power is set to 2.5D, the skew defocus power for oblique rays is the value obtained by adding the actual defocus power to the equivalent spherical power of the RPR.

[0120] This skew defocus power is the value obtained by subtracting the prescribed power from the wavefront power at RPR power evaluation point B on the surface of the spectacle lens facing the eyeball when a ray of light is obliquely incident on point F on the spectacle lens so as to enter the eyeball at a predetermined decentration angle, as shown in Figure 5. This value is close to, but strictly speaking different from, the surface power of the defocus area.

[0121] (Toric shaping of defocused areas) FIG. 7 is a diagram showing an outline of the shape of a spot when the defocus region has a toric shape in one embodiment of the present invention.

[0122] In addition to the oblique power error included in the RPR, off-axis astigmatism also occurs. Here, "oblique" means oblique to the optical axis in frontal vision.

[0123] If the defocus area on the spectacle lens is spherical, when the astigmatism caused by the oblique incidence of light rays and the off-axis astigmatism included in the RPR are added together, astigmatism may still exist. This astigmatism is also called residual astigmatism.

[0124] When the residual astigmatism is large in the actual defocus power, the tangential focal point in the radial direction due to the defocus area and the sagittal focal point in the circumferential direction are different, as shown in Figure 7(a). This is because the distance l from the point in the peripheral part of the retina to the focal point due to the defocus power in the radial direction is different. t and the distance l from the peripheral point of the retina to the focal point due to the defocus power in the circumferential direction. s This leads to differences between the two.

[0125] In this case, as shown in Figure 7(b), the radial size (tangential size) of the shape of the spot formed in the peripheral retina (Blur Spot at peripheral retina in Figure 7(b)) becomes larger than the circumferential size (sagittal size), and as a result, the spot degenerates into an elongated area, which may hinder the intended effect of inhibiting the progression of myopia.

[0126] Furthermore, as shown by the β angle in Figure 7(a), in the peripheral part of the retina, the light rays are often not perpendicular to the retinal tangent plane. As a result, even if the defocus power in the circumferential direction and the defocus power in the radial direction in the defocused region are the same, light spots (spots) of different sizes in the radial and circumferential directions may be formed in the peripheral part of the retina.

[0127] As shown in Figure 7(c), by adopting a toric defocus area, the defocus area becomes closer to an ellipse rather than a circle in plan view, while the spot on the retina can be restored to a nearly circular shape. As a result, the myopia progression suppression function is effectively exhibited. For example, it is preferable that 80% or more of the multiple defocus areas have a toric shape that cancels out the astigmatism component caused by the RPR according to the eccentricity angle corresponding to the position of each defocus area.

[0128] Specifically, it is preferable to design the defocus area to have a toric shape and adjust its astigmatic power and astigmatic axis to reduce the residual astigmatism. In each toric defocus area, the amount of residual astigmatism after canceling the astigmatic component of the RPR is preferably set to 1 / 3 or less of the actual defocus power in each defocus area obtained by subtracting the spherical equivalent power of the RPR according to the decentering angle corresponding to the position of each defocus area from the defocus power in each defocus area.

[0129] However, simply reducing the off-axis astigmatism to zero may not restore the circular spot on the retina, because even if the off-axis astigmatism is reduced to zero, the fact remains that the light rays are not perpendicular to the retinal surface at the periphery of the retina, and as a result, the size of the spot will be larger in the circumferential direction than in the radial direction.

[0130] An example of a toric shape definition is as follows:

number

[0131] (Construction of eyeball model) If we have data on the RPR at each eccentricity angle and data on the axial length (AL), we can construct an eyeball model. More specifically, if we have data on the axial length, we can determine the position of the retina on the optical axis, that is, the position of point A' (the fovea). If we have data on the RPR at each eccentricity angle, we can determine each position of the peripheral retina. As a result, we can construct retinal shape data by connecting the position of point A' (the fovea) with each position of the peripheral retina. This allows us to construct an eyeball model. The eyeball model is used when calculating changes in spot size.

[0132] An example of a method for constructing an eyeball model will be described below. As shown in Figure 2, it is assumed that the eyeball is composed of the anterior and posterior surfaces of the cornea, the pupil, and the anterior and posterior surfaces of the lens.

[0133] The shape of the cornea can be measured or taken from literature. If the axial length is known, the refractive power of the crystalline lens can be determined, and for example, the curvature of the posterior surface of the crystalline lens can be determined.

[0134] It is possible to determine the location of point B' on the retina using the RPR measurement of the off-axis ray at the eccentricity angle α. Using the RPR values ​​at multiple eccentricity angles, it is possible to calculate multiple points on the horizontal meridian of the retina.

[0135] As shown above (expansion of RPR data on the horizontal meridian to lines other than the horizontal meridian), it is possible to define the shape on the horizontal meridian as an extension to the entire retina. If the retinal surface shape is known, the normal to the retina at the point where the light ray reaches the retina can be determined, and the β angle in Figure 7(a) can be determined. In this state, it is possible to track the astigmatism of off-axis rays and determine the radial and circumferential size and shape of the spot on the retina caused by the defocus area on the lens.

[0136] The RPR data for each eccentricity angle may be the RPR data of the subject. In this case, individual design is possible ("individual design mode" described below). On the other hand, instead of the RPR data of the subject, multiple types of RPR data collections may be prepared in advance, and a collection of RPR data that is typical for the subject may be selected ("existing design mode" described below). For example, if the subject is a male aged 10 to 12, the average value of the RPR data for males aged 10 to 12 may be used as the RPR data for the subject.

[0137] The axial length data may also be the data of the subject's axial length. In this case, individual design is possible. On the other hand, as with RPR, instead of the subject's axial length data, multiple types of axial length data collections may be prepared in advance, and a collection of data on the axial length that is typical for the subject may be selected. For example, if the subject is a male aged 10 to 12, the average value of the axial length data for males aged 10 to 12 may be used as the axial length data for the subject.

[0138] (Application example 1) An application example using the content described so far will be described. In this application example, the size of the defocus area is kept the same, while the defocus power of the spherical defocus area is set to a value obtained by adding 2.5D to the equivalent spherical power of the RPR. In other words, an example conforming to the above specific example 1 will be described.

[0139] In the above example, the actual defocus power obtained is close to 2.5D regardless of the decentering angle. Therefore, the following equation holds true:

number

[0140] FIG. 8 is a graph showing the relationship between the power of the defocus area designed to correspond to the case of FIG. 4 and the horizontal cross-sectional position on the spectacle lens.

[0141] The data on the horizontal axis in Fig. 8 is data obtained by calculating the horizontal cross-sectional position on the eyeglass lens from the decentering angle according to the above (position conversion process for calculating the position on the eyeglass lens corresponding to the decentering angle).The defocus power curve of the defocus region on the horizontal cross-sectional position of the lens center is the Defocus SE curve in Fig. 8.

[0142] When the Defocus SE curve in FIG. 8 is expanded to the surface of the spectacle lens using the above [Equation 2], the distribution of the defocus region shown in FIG. 9 is obtained.

[0143] Fig. 9 is a schematic plan view of a spectacle lens corresponding to the case shown in Fig. 4, in which the defocus areas are independently and discretely arranged so that the centers of the defocus areas in the planar spherical shape design form an equilateral triangular array distribution. Darker colors indicate greater defocus power.

[0144] Furthermore, the case where the above (forming the defocus area into a toric shape) is applied to the above example will be illustrated below.

[0145] By making the defocus area of ​​the lens to have a toric surface shape while maintaining the same size, the astigmatism component of the RPR can also be eliminated. For example, the radial defocus power and circumferential defocus power caused by the toric shape of the defocus area are set as follows:

number

[0146] When the contents of both curves in FIG. 8 are expanded to the surface of the eyeglass lens using the above [Equation 2], the distribution of the defocus area shown in FIG. 10 is obtained.

[0147] Figure 10 is a schematic plan view of a spectacle lens corresponding to the case shown in Figure 4, in which each defocus area in Figure 9 has been changed to a toric shape design in plan view, with the major axis in the tangential direction and the minor axis in the sagittal direction. Darker colors indicate greater defocus power. The ratio of the major and minor axes of the ellipse indicates the power difference between the two principal meridians.

[0148] In Figure 10, factors such as light rays being incident obliquely on the spectacle lens and the fact that evaluation point F is a short distance from the lens are ignored. Therefore, although the astigmatic component of the actual defocus power cannot be completely eliminated, it can be reduced. By fine-tuning the power of both principal meridians, it is possible to completely eliminate the astigmatic component. However, as mentioned above, it is also possible to intentionally leave the astigmatic component of the actual defocus power, and design the spot area formed on the retina to be circular due to the remaining astigmatic component. The change in the spot area before and after correction will be explained later (specific examples using application examples 1 and 2).

[0149] (Application example 2) In this application example, contrary to application example 1, the defocus power in the defocus area is kept constant, while the size of the defocus area is set to compensate for the change in spot size due to RPR. In other words, an example conforming to specific example 2 above will be described.

[0150] Fig. 11 is a schematic plan view of a spectacle lens in which each defocus area in Fig. 9 has been modified so that the defocus power of each defocus area is equalized while the size of each defocus area is set to correspond to the case of Fig. 4. The darker the color, the larger the defocus area.

[0151] Furthermore, the above-mentioned (toric shaping of the defocus area) may be applied to the above example. That is, a toric shape is adopted for the defocus area without changing the average power (SE) of the defocus area. Then, the size of each defocus area may be determined so that the toric shape of the defocus area corrects the astigmatism component of the RPR according to the decentering angle corresponding to the position of the defocus area.

[0152] Fig. 12 is a schematic plan view of a spectacle lens corresponding to the case of Fig. 4, in which each defocus area of ​​Fig. 11 has been changed to a toric shape design in plan view, with the major axis in the tangential direction and the minor axis in the sagittal direction. The darker the color, the larger the defocus area.

[0153] (Specific example using application examples 1 and 2) Figure 13 shows the distribution of spot sizes on the retina ((b) in the figure) when the defocus power and size of each defocus area are equal ((a) in the figure). Darker colors indicate smaller spots. 14 shows the distribution of spot sizes on the retina ((c) in the figure) when the defocus power of each defocus region is set while the size of each defocus region is made equal ((a) in the figure, approximately the same as FIG. 9), or when the defocus power of each defocus region is set while the size of each defocus region is made equal ((b) in the figure, approximately the same as FIG. 11). Darker colors indicate greater defocus power. Fig. 15 shows the distribution of spot sizes on the retina ((c) in the figure) when each defocus region in Fig. 9 is changed to a toric shape design in plan view with the major axis in the radial direction (tangential direction) and the minor axis in the circumferential direction (sagittal direction) ((a) in the figure, approximately the same as Fig. 10), or when each defocus region in Fig. 11 is changed to a toric shape design in plan view with the major axis in the radial direction (tangential direction) and the minor axis in the circumferential direction (sagittal direction) ((b) in the figure, approximately the same as Fig. 12). Darker colors indicate greater defocus power.

[0154] As shown in Figure 13(b), the size of the spot differs between the vicinity of the fovea and the peripheral part of the retina, and the spot becomes smaller toward the peripheral part of the retina. This means that the effect of suppressing the progression of myopia is reduced. In this example, the shape of the spot is larger in the circumferential direction than in the radial direction.

[0155] Therefore, when the design of (a) (Application Example 1) or (b) (Application Example 2) in Fig. 14 is adopted, the areas of the respective spot sizes become equal as shown in (c) in Fig. 14. In other words, the actual defocus power that the wearer should obtain is sufficiently obtained even in the peripheral part of the retina.

[0156] On the other hand, the RPR increases toward the retinal periphery, and the astigmatism component increases accordingly. As a result, although the area of ​​each spot size is the same, the spot range becomes elliptical.

[0157] Therefore, the design of (a) in Figure 15 (toric shape of Application Example 1) or (b) (toric shape of Application Example 2) is adopted. In Figures 15 (a) and (b), the power difference between the two principal meridians in each defocus region and the radial and circumferential magnitudes are changed to match the RPR of the case in Figure 3. As a result, as shown in Figure 15 (c), the areas of each spot size are made equal and the spot range can be restored to a circular shape.

[0158] In other words, it is preferable that 80% or more of the multiple defocus areas have a toric shape that cancels out the astigmatism component caused by the RPR according to the decentering angle corresponding to the position of each defocus area, and that the long / short axis ratio (radial size / circumferential size) of the spot size for the wearer is made equal (with a fluctuation range within ±10% (preferably within ±5%, and more preferably within ±1%)).

[0159] (Application example 3) Of course, by changing both the power and size of the defocus area, it is possible to compensate for the changes in the shape and size of the light spot on the retina caused by RPR according to the eccentricity angle corresponding to that position, which is expected to improve the effect of suppressing the progression of myopia.

[0160] <Eyeglass lens design system> The present invention can also be applied to a design system for eyeglass lenses (DIMS). The configuration of the design system for eyeglass lenses is as follows. The technical idea of ​​the present invention is also reflected in a system for manufacturing eyeglass lenses designed by this system. The technical idea of ​​the present invention is also reflected in a system for supplying eyeglass lenses designed by this system. "Select an individual design mode in which at least one of the defocus power and size of each defocus area is set so as to compensate for a change in spot size on the retina due to the relative peripheral refraction (RPR) corresponding to the decentration angle from the frontal view on the retina of the wearer's eye in more than half of the plurality of defocus areas, or an existing design mode in which one of a plurality of design data prepared in advance including the base region and the plurality of defocus regions, the design data having different patterns of the defocus regions, is adopted; A spectacle lens design system comprising a first selection unit that selects

[0161] The "pattern of defocus regions" in the above paragraph refers to at least one of the distribution of defocus power, arrangement (eg, whether it has a honeycomb structure, spacing distance, etc.), shape, and size of each defocus region.

[0162] A spectacle lens design system is exemplified as the supply system. A specific example of the configuration of the supply system is as follows: The present invention is not limited to the following specific example.

[0163] FIG. 16 is a schematic diagram showing an example of the configuration of a spectacle lens supply system according to one aspect of the present invention.

[0164] The illustrated eyeglass lens supply system 1 is configured such that an ordering device 2 for ordering eyeglass lenses and an order-receiving device 3 for receiving orders for eyeglass lenses are connected to each other via a communication network 4 so that they can communicate with each other. The ordering device 2 is installed and used, for example, in an eyeglass shop, and the order-receiving device 3 is installed and used, for example, in an eyeglass lens manufacturing factory. The communication network 4 is configured, for example, by the Internet or a dedicated line. In this eyeglass lens supply system 1, information necessary for ordering eyeglass lenses is sent to the order-receiving device 3 via the communication network 4. The order-receiving device 3 then performs the necessary eyeglass lens processing using the received information, and finally, eyeglass lenses that have been determined to be non-defective after inspection, etc. are delivered to the eyeglass shop that placed the order. The eyeglass lens processing includes polishing the optical surface of the eyeglass lens and edging for framing.

[0165] In the eyeglass lens supply system 1 configured as above, the correspondence relationship between the ordering device 2 and the order-receiving device 3 may be any of a 1:1 correspondence relationship, an m:1 correspondence relationship (m is a natural number equal to or greater than 2), a 1:n correspondence relationship (n is a natural number equal to or greater than 2), or an m:n correspondence relationship. The ordering device 2 and the order-receiving device 3 may be installed in the same country or in different countries. Furthermore, although not shown, various servers (e.g., data servers) may be connected to the communication network 4, and data may be exchanged between the servers and the ordering device 2 or the order-receiving device 3 as needed.

[0166] The ordering device 2 is configured with computer hardware resources and includes an input unit 5, a computer unit 6, and a display unit 7. The input unit 5 is used to input various data (information) to the ordering device 2. The input unit 5 can be configured using input operation devices such as a keyboard, a mouse, or a touch panel. Data input via the input unit 5 includes ordering information D1. If there is a possibility that the individual design mode will be selected, the data may also include an RPR value D2 of the customer (future wearer), an axial length value D3 of the customer (future wearer), etc.

[0167] The ordering information D1 includes eyeglass lens prescription information including the addition power of the eyeglass lens (distance vision power, near vision power) and astigmatism axis, frame information including the type, material, size, and frame shape data of the eyeglass frame, and layout information used to align the eyeglass lens and eyeglass frame.

[0168] The RPR value D2 is the RPR value described above, and is an RPR value according to the wearer, that is, an RPR value according to the direction of the horizontal meridian and the eccentricity angle.

[0169] The axial length value 3 is the axial length value that has been described so far.

[0170] (Computer Department) The computer unit 6 is configured using a central processing unit (CPU), read only memory (ROM), random access memory (RAM), hard disk drive (HDD), etc., which are hardware resources of a computer.

[0171] As shown in Fig. 16, the computer unit 6 includes a first selection unit 11, a second selection unit 12, an order processing unit 13, and a storage unit 14. Each functional unit is realized using the hardware resources of the computer described above. Each functional unit of the computer unit 6 described above is realized, for example, by the CPU reading a program stored in a ROM or HDD into a RAM and executing it. In this case, the program can be extracted as one aspect of the present invention.

[0172] (Order Processing Department) The order processing unit 13 performs processing for ordering eyeglass lenses. Specifically, the order processing unit 13 extracts information necessary for ordering eyeglass lenses from the information input by the input unit 5, and transmits this information to the order-receiving device 3 via the communication network 4. The order processing unit 13 also performs processing for transmitting information (manufacturer, type, etc.) specifying the eyeglass lenses that have been finally decided (confirmed) by the eyeglass store staff with the consent of the wearer to the order-receiving device 3 via the communication network 4.

[0173] (Storage part) The storage unit 14 is used to store various data handled by the ordering device 2. The data stored in the storage unit 14 includes input data, calculation results, etc. When the individual design mode is adopted, data on the wearer's RPR and axial length are included. This information is stored in the storage unit 14 in advance, and the first selection unit 11 or the second selection unit 12 refers to this information as necessary.

[0174] (First selection section) The first selection unit 11 has a function of selecting whether to take into account the RPR according to the axial length of the wearer and the decentration angles of the multiple eyes in the design of more than half of the multiple defocus areas to obtain individual design data (FIG. 16), or to select from multiple design data prepared in advance without taking into account the RPR.

[0175] As multiple design data, for example, data in which the size of each defocus area is made equal and the defocus power of the defocus areas is uniformly set to 1.5D (existing design data 1 in Figure 16), data in which the defocus power is set to 2.5D (existing design data 2 in Figure 16), and data in which the defocus power is set to 3.5D (existing design data 3 in Figure 16) may be prepared.

[0176] Of course, as mentioned in <Spectacle Lenses>, preparing a defocus area that reflects the RPR of each wearer is preferable in terms of the effect of inhibiting the progression of myopia. On the other hand, in terms of the cost paid by the wearer, it is cheaper to set a uniform defocus power for each defocus area. Furthermore, if a design that reflects the typical axial length and typical RPR pattern is prepared, it will be possible to provide lenses at a relatively reasonable price.

[0177] Furthermore, from the viewpoint of manufacturing eyeglass lenses, it is possible to design eyeglass lenses more quickly by preparing multiple setting patterns for defocus areas in advance and selecting from among them. Also, when preparing semi-finished lenses in which defocus areas that reflect multiple setting patterns are formed in advance on a base area of ​​a predetermined curvature, it is possible to reduce the number of types of semi-finished lenses that need to be prepared. This leads to reduced inventory and is economically advantageous.

[0178] According to one aspect of the present invention, multiple designs of defocus areas with uniform defocus power are prepared, and / or multiple designs that reflect data on typical axial lengths and typical RPR are prepared, and simulations are performed using the customer's axial lengths (using typical values ​​in some cases) and RPR measurements (using typical values ​​in some cases), making it possible to select, for example, a design that causes the least change in the spot formed on the retina by the defocus area.

[0179] The following methods can be used to select a design that results in the least spot change. "In the existing design mode, from the plurality of design data, the design data that minimizes the change in spot size on the retina due to the RPR of the wearer in each defocus region is adopted."

[0180] The design data that minimizes the change in spot size may be determined by using, for example, the least squares method, and selecting the design data that minimizes the change in spot size at each decentering angle.

[0181] In summary, in one aspect of the present invention, depending on the intentions of the wearer or the client (or the recipient), it is possible to select between a method of individually designing a DIMS lens that reflects the RPR described in <Eyeglass Lenses>, and a method of extracting a design that best reduces the influence of RPR from multiple DIMS designs prepared in advance.

[0182] (Second selection section) In one aspect of the present invention, it is preferable to include a second selection unit 12. When RPR is taken into consideration in the design, the second selection unit 12 has a function of selecting each design parameter. Examples of the selection of each design parameter include selecting whether the surface shape of the defocus region is spherical or toric, selecting whether the diameter of the defocus region is 1.0 mm or 0.8 mm, and selecting the interval between defocus regions.

[0183] The second selection unit 12 may further be provided with a function to select whether to select one from a plurality of design data as described above, or to prepare a defocus area that completely reflects the RPR of each wearer.

[0184] (calculation section) In this case, the calculation unit 15 may calculate the defocus power to be set in each defocus area after taking the RPR into consideration. This calculation unit may calculate the defocus power of the defocus area that completely reflects the RPR of each wearer. The calculation result may be used as material when selecting one from multiple design data using the second selection unit 12. The calculation unit may be provided in the order-receiving device 3, or may be provided in a separate device on the network other than the order-receiving device 3 and the ordering device 2, or in the cloud. These functions may be provided in a control unit (not shown) of the computer unit 6.

[0185] (Display) The display unit 7 is configured using, for example, a liquid crystal display device, an organic EL display device, etc. This feature may be provided in both the ordering-side device 2 and the order-receiving-side device 3.

[0186] The first selection unit 11 and the second selection unit 12 may be provided in the order-receiving device 3, or may be provided in a separate device on a network other than the order-receiving device 3 and the ordering device 2, or in the cloud. Furthermore, the first selection unit 11 may be provided in the ordering device 2, while the second selection unit 12 may be provided in the order-receiving device 3. Furthermore, the first selection unit 11 and the second selection unit 12 may be configured as a single unit. For example, the control unit (not shown) of the computer unit 6 may be provided with these functions.

[0187] A spectacle lens supply system according to another embodiment of the present invention makes it possible to select whether to individually design the spectacle lenses to be supplied in accordance with the RPR of the wearer, or to adopt an existing design. Using the RPR of the wearer, it is possible to select a design that minimizes changes in the size and shape of the spot formed on the retina from among multiple designs for the shapes and sizes of defocus areas prepared in advance.

[0188] In addition, in the spectacle lens supply system according to another embodiment of the present invention, it is assumed that the RPR according to the decentering angle of the wearer's eye is selected to be taken into account in the design of more than half of the multiple defocus areas, but the technical idea of ​​the present invention is also reflected in a spectacle lens supply system that decides to take this into account from the beginning. In other words, this spectacle lens supply system is also a spectacle lens design system that reflects the contents of the description of <Spectacle Lens Design Method>.

[0189] The technical scope of the present invention is not limited to the above-described embodiments, but also includes various modifications and improvements within the scope of the specific effects that can be obtained by the constituent elements of the invention and their combinations. [Explanation of symbols]

[0190] 1. Eyeglass lens supply system 2...Ordering device 3...Order-receiving device 4. Communication network 5...Input section 6...Computer section 11...First selection section 12...Second selection section 13...Order processing section 14...Storage section 15...Arithmetic section

Claims

1. a base region that causes a light beam incident from the object-side surface to exit from the eyeball-side surface and converge on the retina via the eyeball; a plurality of defocus regions in contact with the base region, the defocus regions having a property that a light beam passing through at least a part of the defocus regions is incident on a retina as divergent light; Equipped with A spectacle lens in which, in more than half of the multiple defocus areas, the size of the defocus area on the ear side of the spectacle lens is larger than the size of a defocus area located on the nose side of the spectacle lens at the same distance from the center of the spectacle lens as the ear side defocus area, so as to compensate for a change in spot size on the retina due to the relative peripheral refraction (RPR) corresponding to the decentration angle of the wearer's eyeball, where the RPR of the nose side portion of the retina peripheral area is larger than the RPR of the ear side portion.

2. In 80% or more of the plurality of defocus regions, The spectacle lens of claim 1 , wherein the defocusing power of each defocusing region is equal.

3. 3. The eyeglass lens according to claim 1, wherein 80% or more of the plurality of defocus areas have a toric shape that cancels out the astigmatism component caused by the RPR according to the decentering angle corresponding to the position of each defocus area.

4. 4. The eyeglass lens according to claim 3, wherein in each defocus region of a toric shape, the amount of remaining astigmatism after canceling out the astigmatism component of the RPR is ⅓ or less of the actual defocus power in each defocus region after subtracting the spherical equivalent power of the RPR according to the decentering angle corresponding to the position of each defocus region from the defocus power in each defocus region.

5. 5. The eyeglass lens according to claim 1, wherein in 80% or more of the plurality of defocus areas, an actual defocus power in each defocus area after subtracting an equivalent spherical power of the RPR according to an eccentric angle corresponding to the position of each defocus area from the defocus power in each defocus area is in a range of 1.0 to 4.5D.

6. The eyeglass lenses are myopia progression suppression lenses. The eyeglass lens according to any one of claims 1 to 5.

7. a base region that causes a light beam incident from the object-side surface to exit from the eyeball-side surface and converge on the retina via the eyeball; a plurality of defocus regions in contact with the base region, the defocus regions having a property that a light beam passing through at least a part of the defocus regions is incident on a retina as divergent light; A method for designing eyeglass lenses, comprising: A method for designing eyeglass lenses, comprising a setting step of setting at least one of the defocus power and the size of each defocus area so as to compensate for a change in spot size on the retina due to a relative peripheral refraction (RPR) according to an eccentricity angle of the wearer's eyeball in at least half of the plurality of defocus areas.

8. 8. The method for designing eyeglass lenses according to claim 7, wherein the spot size is obtained based on retinal shape data constructed from data on a plurality of RPRs corresponding to mutually different decentration angles and data on the axial length of the wearer.

9. a position conversion step of calculating a position on the eyeglass lens corresponding to the decentering angle, or calculating the decentering angle corresponding to the position on the eyeglass lens; the setting step of setting at least one of the defocus power and the size of each defocus area so as to compensate for a change in spot size on the retina due to the RPR at the decentration angle corresponding to the position; and 9. The method for designing eyeglass lenses according to claim 7 or 8, wherein, in the position conversion step, a region having an optical center on the eyeglass lens as a center and a radius of one value within a range of 2 to 6 mm is defined as a rotation coverage range, and the decentering angle corresponding to a position within this range is set to zero, and the decentering angle corresponding to a predetermined position on the eyeglass lens outside the rotation coverage range is set to an angle formed by a line connecting the predetermined position and the entrance pupil of the eyeball and the optical axis of the eyeball after rotating the eyeball so that the line of sight passes through a point on the boundary line of the rotation coverage range that is on a line formed by the predetermined position and the optical center on the eyeglass lens.

10. a base region that causes a light beam incident from the object-side surface to exit from the eyeball-side surface and converge on the retina via the eyeball; a plurality of defocus regions in contact with the base region, the defocus regions having a property that a light beam passing through at least a part of the defocus regions is incident on a retina as divergent light; A spectacle lens design system comprising: Selecting an individual design mode in which at least one of the defocus power and the size of each defocus area is set so as to compensate for a change in spot size on the retina due to a relative peripheral refraction (RPR) according to the decentration angle of the wearer's eyeball in at least half of the plurality of defocus areas, or an existing design mode in which one of a plurality of design data prepared in advance including the base region and the plurality of defocus regions, the design data having different patterns of the defocus regions, is adopted; A spectacle lens design system comprising a first selection unit that selects:

11. 11. The eyeglass lens design system according to claim 10, wherein in the existing design mode, from the plurality of design data, design data that minimizes the change in spot size on the retina due to the RPR of the wearer in each defocus area is adopted.

12. 12. The eyeglass lens design system according to claim 10, wherein the spot size is obtained based on retinal shape data constructed from data on a plurality of RPRs corresponding to mutually different decentration angles and data on the axial length of the wearer.

Images