Eyeglass lenses, methods for manufacturing eyeglass lenses, methods for designing eyeglass lenses, eyeglasses, and methods for manufacturing eyeglasses.

Abstract

To provide spectacle lenses that suppress the progression of refractive errors such as myopia. [Solution] An eyeglass lens comprising a functional region having a base region that causes a light beam incident from the object-side surface to be emitted from the eye-side surface, enter the wearer's pupil, and converge on the retina, and a retinal non-converging region that causes a light beam incident from the object-side surface to be emitted from the eye-side surface, but does not converge the light beam that enters the wearer's pupil on the retina, wherein at least a part of the retinal non-converging region is a buffer region capable of canceling out local negative astigmatism caused by spherical aberration of the eye at a part of the distribution of said astigmatism, and the surface shape of each buffer region is a toric surface with an axial direction in the circumferential direction and is elongated in the circumferential direction when viewed from above.

Description

Technical Field

[0001] The present invention relates to spectacle lenses, a method for manufacturing spectacle lenses, a method for designing spectacle lenses, spectacles, and a method for manufacturing spectacles.

Background Art

[0002] As a spectacle lens for suppressing the progression of refractive anomalies such as myopia, there is one in which a plurality of island-shaped regions (alternatively referred to as "second refractive regions" or "micro convex portions") having a refractive power plus than the prescribed refractive power are formed on the lens (see, for example, Patent Document 1). In Patent Document 1, the region that provides the prescribed refractive power is referred to as the first refractive region. This first refractive region is also referred to as the base region.

[0003] According to the spectacle lens of this configuration, among the light beams that enter from the object side surface and exit from the eyeball side surface, the light beams that pass through other than the micro convex portions are focused on the wearer's retina, but the light beams that pass through the micro convex portions are focused at a position in front of the retina, thereby suppressing the progression of myopia.

[0004] In

[0094] of Patent Document 2, it is described that by changing the above micro convex portion to a concave portion, a spectacle lens having a function of suppressing the progression of hyperopia can be obtained. In this specification, as an expression that collectively refers to the above myopia progression suppression effect and hyperopia progression suppression effect (more precisely, hyperopia reduction effect), it is also referred to as refractive anomaly progression suppression or reduction effect. Hereinafter, the myopia progression suppression effect will be exemplified.

[0005] On pages 20 and 21 of Patent Document 3, in accordance with the asymmetry of the peripheral part of the retina, by increasing or decreasing the refractive power and cylindrical power of the micro convex portions asymmetrically in the circumferential direction from the center to the peripheral part, it is described that a spectacle lens having a high myopia progression suppression effect can be obtained.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

[0007] The human eye exhibits spherical aberration. While various factors contribute to spherical aberration, including the cornea and lens, for the sake of clarity, it will hereafter be simply referred to as "spherical aberration of the eye." Even if the surface shape of the minute protrusion described in Patent Document 1 were spherical, it would still be difficult to focus due to the spherical aberration of the eye. This effect also appears near the center of the retina, which is not considered in Patent Document 3.

[0008] One embodiment of the present invention provides spectacle lenses and related technologies that can reduce the influence of spherical aberration of the eye on the effect of suppressing or mitigating the progression of refractive errors. In another embodiment of the present invention, an eyeglass lens and related technology are provided that can exhibit an equivalent effect of suppressing or reducing the progression of refractive errors regardless of the degree of spherical aberration in the eye. [Means for solving the problem]

[0009] A first aspect of the present invention is: A base region that directs a light beam entering from the object-side surface, exits from the eye-side surface, enters the wearer's pupil, and focuses onto the retina, A retinal non-focusing region is created where the light beam incident from the object side is emitted from the eyeball side, while the light beam incident within the wearer's pupil is not focused onto the retina. It has a functional area that has, At least a portion of the aforementioned non-converging region on the retina is a buffer region capable of canceling out localized negative astigmatism caused by spherical aberration of the eye at a portion of the distribution of said astigmatism. The surface shape of the buffer region is a toric surface with an axial direction in the circumferential direction, and in a plan view, it is elongated along the circumferential direction, in the eyeglass lens.

[0010] A second aspect of the present invention is: In the planar view of the functional region, any non-converging region on the retina within a band-shaped region consisting of a collection of circles with a diameter of 4 mm, the center of which passes through a predetermined range of at least one diameter extending from the center of the lens, is the buffer region. The spectacle lens according to the first embodiment, wherein at least three buffer regions are dispersed within any circle with a diameter of 4 mm within the aforementioned band-shaped region.

[0011] A third aspect of the present invention is: The dispersion of the buffer regions is such that the first interval, which is the length of the line segment connecting the centers of two buffer regions, and the second interval, which is the distance between the center of another buffer region that is closest to the line segment and whose center lies on the normal to the line segment and the line segment, are both less than 2 mm, in the spectacle lens according to the second embodiment.

[0012] A fourth aspect of the present invention is: The spectacle lens according to any one of the first to third embodiments, wherein the absolute value of the astigmatism present in the buffer region is 0.25 to 0.50 D.

[0013] A fifth aspect of the present invention is: The non-converging region on the retina is a spectacle lens according to any one of the first to fourth embodiments, having a shape that protrudes from the base region.

[0014] A sixth aspect of the present invention is: The spectacle lens according to the fifth embodiment, wherein the projection distance of the non-focusing region on the retina from the base region is greater than 1.00 μm.

[0015] A seventh aspect of the present invention is: The aforementioned non-converging region on the retina includes at least non-converging regions A1 and B1, At least the non-converging region B1 on the retina is a buffer region, In a plan view, the non-converging region B1 on the retina that is farther from the lens center is longer along the circumferential direction than the non-converging region A1 on the retina that is closer to the lens center, and is the spectacle lens according to any one of the first to sixth aspects.

[0016] The eighth aspect of the present invention is Among the non-converging regions on the retina on each circumference, there are two straight lines having a relationship that the absolute value of the coma aberration of the non-converging region on the retina on the straight line passing through the lens center is large, and the absolute value of the coma aberration of the non-converging region on the retina on the straight line perpendicular to the straight line and passing through the lens center is small, and it is the spectacle lens according to any one of the first to seventh aspects.

[0017] The ninth aspect of the present invention is The spectacle lens according to the eighth aspect, wherein a mark presenting information that the value of the coma aberration varies according to the circumferential position in each of the buffer regions is provided on the spectacle lens.

[0018] The tenth aspect of the present invention is The spectacle lens includes a lens substrate and a laminated film provided so as to cover the lens substrate. The lens substrate a first refractive region of the substrate serving as a base for the base region, a second refractive region of the substrate serving as a base for the non-converging region on the retina, and has The spectacle lens according to any one of the first to ninth aspects, wherein the surface shape of the second refractive region of the substrate in the buffer region that serves as a base is a toric surface having an axial direction in the circumferential direction and is elongated along the circumferential direction in a plan view.

[0019] The eleventh aspect of the present invention is [[ID= The spectacle lens according to the tenth embodiment, wherein at least three substrate second refractive regions are dispersed within any circle with a diameter of 4 mm within the aforementioned band-shaped region.

[0020] A twelfth aspect of the present invention is: The spectacle lens according to the eleventh embodiment is characterized in that the dispersion of the second refractive region is such that the third interval, which is the length of the line segment connecting the centers of the second refractive regions of two substrates, and the fourth interval, which is the distance between the line segment and the center of another second refractive region of a substrate that is closest to the line segment and whose center lies on the normal to the line segment, are both less than 2 mm.

[0021] A thirteenth aspect of the present invention is: The second refractive region of the substrate that forms the basis of the non-converging region on the retina includes at least the second refractive regions a1 and b1 of the substrate. At least the second refractive region b1 of the substrate is the base of the buffer region, In a plan view, the second refractive region b1 of the substrate, which is further from the center of the lens, has a longer shape in the circumferential direction compared to the second refractive region a1 of the substrate, which is closer to the center of the lens, as described in any one of the 10th to 12th embodiments.

[0022] A fourteenth aspect of the present invention is: The spectacle lens according to any one of the 10th to 13th embodiments is characterized in that the second refractive region of the substrate has a shape that protrudes from the first refractive region of the substrate.

[0023] A fifteenth aspect of the present invention is: The spectacle lens according to the 14th embodiment, wherein the projection distance of the second refractive region of the substrate from the first refractive region of the substrate is greater than 1.00 μm.

[0024] A sixteenth aspect of the present invention is: The spectacle lens according to any one of the 10th to 15th embodiments, wherein the thickness of at least one of the laminated films is unevenly distributed around the second refractive region of the substrate, and the astigmatism value differs depending on the circumferential position in each of the buffer regions on each circumference.

[0025] A 17th aspect of the present invention is: An eyeglass lens according to any one of the 10th to 15th embodiments, having a central clear region surrounded by the annular functional region.

[0026] An eighteenth aspect of the present invention is: The center of the aforementioned central clear region is located at the geometric center of the lens, as described in the 17th embodiment of the spectacle lens.

[0027] A 19th aspect of the present invention is: The spectacle lens according to the 17th embodiment is such that the center of the central clear region is shifted toward the nose with respect to the geometric center of the lens.

[0028] A 20th aspect of the present invention is: A base region that directs a light beam entering from the object-side surface, exits from the eye-side surface, enters the wearer's pupil, and focuses onto the retina, A retinal non-focusing region is created where the light beam incident from the object side is emitted from the eyeball side, while the light beam incident within the wearer's pupil is not focused onto the retina. A method for manufacturing spectacle lenses having a functional region having, At least a portion of the aforementioned non-focusing region on the retina is a buffer region that cancels out localized negative astigmatism caused by spherical aberration of the eye at a portion of the distribution of said astigmatism. The aforementioned spectacle lens comprises at least a lens substrate, The aforementioned lens substrate is The base region is formed by a first refractive region of the substrate, The base material second refractive region that forms the basis of the non-converging region on the retina, It has, The process involves turning the mold on a lathe so that the surface shape of the second refraction region of the base material that forms the basis of the buffer region is a toric surface having an axial direction in the circumferential direction, and in a plan view, it has an elongated shape along the circumferential direction. A molding process in which the lens substrate is formed using a mold after lathe machining, This is a method for manufacturing eyeglass lenses.

[0029] A 21st aspect of the present invention is: The method for manufacturing eyeglass lenses according to the 20th embodiment is to perform the turning process on a mold so that, in a plan view of the lens substrate, the surface shape of the second refractive region of the substrate within a band-shaped region consisting of a collection of circles with a diameter of 4 mm, the centers of which pass through a predetermined range of at least one diameter extending from the center of the lens, is a toric surface having an axial direction in the circumferential direction, and in a plan view, it has an elongated shape along the circumferential direction, and so that at least three second refractive regions of the substrate are dispersed within any circle of a diameter of 4 mm within the band-shaped region.

[0030] A 22nd aspect of the present invention is: The method for manufacturing spectacle lenses according to the 21st embodiment is such that the dispersion of the second refractive region is such that the third interval, which is the length of the line segment connecting the centers of the second refractive regions of two substrates, and the fourth interval, which is the distance between the center of another second refractive region of a substrate that is closest to the line segment and whose center lies on the normal to the line segment and the line segment, are both less than 2 mm.

[0031] A 23rd aspect of the present invention is: The second refractive region of the substrate that forms the basis of the non-converging region on the retina includes at least the second refractive regions a1 and b1 of the substrate. At least the second refractive region b1 of the substrate is the base of the buffer region, The method for manufacturing eyeglass lenses according to any one of the 20th to 22nd embodiments, wherein when machining a mold on a lathe to form the lens base material, the lathe machining process is performed to machine the mold so that, in a plan view, the second refractive region b1 of the base material, which is further from the center of the lens, is elongated in the circumferential direction compared to the second refractive region a1 of the base material, which is closer to the center of the lens.

[0032] A 24th aspect of the present invention is: A method for manufacturing eyeglass lenses according to any one of the 20th to 23rd embodiments, wherein in the turning process, the portion of the mold corresponding to the second refractive region of the substrate is recessed compared to the portion corresponding to the first refractive region of the substrate, so that the second refractive region of the substrate has a shape that protrudes from the first refractive region of the substrate.

[0033] A 25th aspect of the present invention is: The method for manufacturing spectacle lenses according to the 24th embodiment, wherein the recess distance is greater than 1.00 μm.

[0034] A 26th aspect of the present invention is: The process further includes a lamination step in which a laminated film is formed to cover the lens substrate obtained using a mold after lathe machining, A method for manufacturing spectacle lenses according to any one of the 20th to 25th embodiments, wherein at least one of the laminated films is formed by a dip method, thereby causing the thickness of the film to be unevenly distributed around the second refractive region of the substrate, and causing the astigmatism to differ depending on the circumferential position in each of the buffer regions.

[0035] A 27th aspect of the present invention is: The method for manufacturing eyeglass lenses according to the 26th embodiment is such that, among the non-focusing regions on the retina on each circumference, there exist two straight lines such that the absolute value of astigmatism in the non-focusing region on the retina that lies on a straight line passing through the center of the lens is large, and the absolute value of astigmatism in the non-focusing region on the retina that is perpendicular to the said straight line and lies on a straight line passing through the center of the lens is small.

[0036] A 28th aspect of the present invention is: The method for manufacturing an eyeglass lens according to the 27th embodiment further comprises a marking step of providing a mark on the eyeglass lens that presents information that the value of astigmatism differs depending on the circumferential position in each of the aforementioned buffer regions.

[0037] A 29th aspect of the present invention is: A pair of eyeglasses in which an eyeglass lens described in any one of the 1st to 19th embodiments is fitted into a frame.

[0038] A 30th aspect of the present invention is: This method of manufacturing eyeglasses involves determining the orientation of the eyeglass lens using the mark on the eyeglass lens described in the ninth aspect as a guide, according to the magnitude of spherical aberration in the wearer's eye, and then fitting the eyeglass lens into the frame.

[0039] A 31st aspect of the present invention is: Let V be the absolute value of the difference between the astigmatism of light incident on the upper retina and the astigmatism of light incident on the lower retina when a person wearing eyeglass lenses has uncorrected vision. When the wearer is wearing eyeglass lenses, let V' be the absolute value of the difference between the astigmatism of light passing through the non-focusing region on the retina and incident on the upper retina, and the astigmatism of light incident on the lower retina. This is a method for designing eyeglass lenses, in which the mounting direction of the eyeglass lens described in any one of the first to 19 embodiments is determined such that V' is larger than V.

[0040] A 32nd aspect of the present invention is: A method for manufacturing eyeglasses, comprising framing the eyeglass lenses according to the orientation determined by the design method described in the 31st aspect.

[0041] Regarding the size of the non-focusing region on the retina, it is preferable that the following conditions be met. We focus on the relative frequency of the non-converging region on the retina with respect to the base region. Let L (in units: D) be the absolute value of this relative frequency. If the non-converging region on the retina is elongated in the circumferential direction, astigmatism of 0.25 to 0.50 D can be introduced if the ratio M of the length of the long side (circumferential length in planar view) to the length of the short side (radial length in planar view) of the non-converging region on the retina 3a satisfies the following formula. 0.25 <L-L / M 2 <0.50 It is more likely that L will be between 3.00 and 5.00D, in which case M will be around 1.025 to 1.085. [Effects of the Invention]

[0042] In one embodiment of the present invention, the influence of spherical aberration of the eye on the effect of suppressing or reducing the progression of refractive errors can be reduced. In another embodiment of the present invention, it is possible to achieve an equivalent effect of suppressing or reducing the progression of refractive errors regardless of the degree of spherical aberration in the eye. [Brief explanation of the drawing]

[0043] [Figure 1A] Figure 1A shows a typical wavefront map of an eye with spherical aberration. [Figure 1B] Figure 1B shows negative local astigmatism in relation to Figure 1A, indicated by hatched arrows. [Figure 1C] Figure 1C shows the distribution of the absolute value of astigmatism (vertical axis) in a horizontal cross-section passing through the center of the eye (distance from the center is indicated by the sign H: horizontal axis). [Figure 2A] Figure 2A is a graph that assumes a pupil with zero spherical aberration and a second refractive region with no aberration (spherical), with the vertical axis being VSOTF (Visual Strehl ratio based on OTF) and the horizontal axis being the amount of defocus (unit: D (diopter), zero being the retinal position). [Figure 2B] Figure 2B is a graph similar to Figure 2A, but it assumes a pupil with a spherical aberration of an absolute value of 0.080 μm and a second refractive region (spherical shape) with no aberration. [Figure 2C] Figure 2C is a graph similar to Figure 2A, but it assumes a pupil with a spherical aberration of 0.080 μm in absolute value and a second refractive region with aberration. [Figure 3A] Figure 3A is a diagram comparing the size of the spectacle lens (right figure) and the size of the pupil (lower left figure) related to Figure 2C, and is an explanatory diagram in which the axis direction of the astigmatism provided in each second refractive region is indicated by a white arrow. [Figure 3B] Figure 3B is an explanatory diagram of the spectacle lens related to Figure 2C (left figure), and an enlarged explanatory diagram (right figure) showing the axis direction of the astigmatism (white arrows) provided in each second refractive region of the spectacle lens related to Figure 2C and the axis direction of the astigmatism (hatched arrows) of the eye. [Figure 4A]Figure 4A is an explanatory diagram showing the arrangement of a second refractive region that satisfies the dispersion requirements defined in one aspect of the present invention. [Figure 4B] Figure 4B is an explanatory diagram showing the arrangement of a second refractive region that does not satisfy the dispersion requirements defined in one aspect of the present invention. [Figure 5A] Figure 5A is the same diagram as the right-hand diagram in Figure 3A, and is an explanatory diagram in which the axial direction of the astigmatism provided in each second refractive region is indicated by a white arrow. [Figure 5B] Figure 5B is an explanatory diagram showing the axial direction of astigmatism present in the second refractive region of each substrate by white arrows, resulting from film deposition using the dip method. [Figure 5C] Figure 5C is an explanatory diagram showing the axis direction of astigmatism present in each second refractive region of the spectacle lens shown in Figure 5A, when a film is deposited using the dip method, and the amount of astigmatism is indicated by the length of the white arrow. [Figure 6A] Figure 6A is the same diagram as the right-hand diagram in Figure 3A, and is an explanatory diagram that uses arrows to indicate the positions that the line of sight frequently passes through when wearing eyeglass lenses. [Figure 6B] Figure 6B is the same diagram as Figure 5C, and is an explanatory diagram showing how the orientation of the spectacle lens was determined so that the buffering area where astigmatism is maximized is positioned at the location where the line of sight frequently passes, in order to accommodate a child whose spherical aberration of the eye is an absolute value of 0.080 μm. [Figure 6C] Figure 6C is an explanatory diagram showing how the orientation of the spectacle lens was determined so that the second refractive region, which has zero astigmatism, is positioned at a location frequently passed through by the line of sight, in order to accommodate children whose eyes have zero spherical aberration. [Figure 7] Figure 7 is an explanatory diagram illustrating an example of the definition of the boundary between the functional region and the central clear region, and an explanatory diagram illustrating an example of the definition of the boundary between the functional region and the outer clear region. [Modes for carrying out the invention]

[0044] Embodiments of the present invention will be described below. The following description based on the drawings is illustrative, and the present invention is not limited to the illustrated embodiments.

[0045] The spectacle lenses described herein have an object-facing surface and an eye-facing surface. The "object-facing surface" is the surface that faces the object when the spectacle lenses are worn by the wearer, and the "eye-facing surface" is the opposite surface, that is, the surface that faces the eye when the spectacle lenses are worn by the wearer. 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-facing surface and an eye-facing surface.

[0046] In this specification, the horizontal direction when wearing eyeglass lenses is defined as the X direction, the vertical direction (up and down) as the Y direction, and the thickness direction of the eyeglass lenses, which is perpendicular to the X and Y directions, as the Z direction. The Z direction is also the optical axis direction of the eyeglass lenses. The origin is the center of the lens. The center of the lens refers to the optical center or geometric center of the eyeglass lens. In this specification, examples are given where the optical center and the geometric center approximately coincide. To the wearer, the direction to the right (3 o'clock) is the +X direction, to the left (9 o'clock) is the -X direction, upward (12 o'clock) is the +Y direction, downward (6 o'clock) is the -Y direction, the direction towards the object is the -Z direction, and the opposite direction (away from the wearer) is the +Z direction. In this specification, "planar view" refers to the state when viewed from the -Z direction to the +Z direction. The defocus power described later also follows this Z direction sign. Each figure in this application illustrates the case when viewing the right eye lens in a planar view, with the nasal direction being the +X direction and the temporal direction being the -X direction when the right eye lens is worn. Furthermore, if the functional area is provided only on the outermost surface on the eyeball side, the view from the -Z direction to the +Z direction may be considered as a planar view. Hereafter, when discussing "positions" such as the eye point and geometric center in eyeglass lenses, unless otherwise specified, it refers to the position in a planar view.

[0047] In this specification, "~" refers to a value greater than or equal to a specified value and less than or equal to a specified value. Hereafter, a symbol will be used, but only for the first occurrence of the item; thereafter, the symbol will be omitted.

[0048] <Knowledge leading up to the present invention> The inventors investigated spherical aberration in the eye. Figure 1A shows a typical wavefront map of an eye with spherical aberration. Figure 1B shows negative local astigmatism in relation to Figure 1A, indicated by hatched arrows. The vertical direction is the up-and-down direction, and the horizontal direction is the left-and-right direction. The diameter of the wavefront map is 4 mm, assuming a typical pupil diameter. The darker the color in the map, the more the wavefront lags. Where the color in the map changes quadratically, it means that there is a localized frequency in the radial direction. In other words, the eye shown in Figure 1A has negative localized astigmatism as indicated by the hatched arrow in Figure 1B.

[0049] In this specification, the spherical aberration value is assumed to be an absolute value of 0.080 μm. The reason for this is as follows.

[0050] Reports on spherical aberration in the eyes of children are presented in the following literature (especially Figure 4). "Athaide HV, Campos M, Costa C. Study of ocular aberrations with age. Arq BrasOftalmol. 2009 Sep-Oct;72(5):617-21. doi: 10.1590 / s0004-27492009000500003. PMID:20027396." According to the above-mentioned literature, the spherical aberration of children's eyes is distributed within the interquartile range of -0.08 to +0.12 μm. The results in the above-mentioned literature were measured with a dilated pupil diameter of 6.5 mm, and it is necessary to convert this to a more typical pupil diameter of 4 mm. Furthermore, there is a roughly proportional relationship between pupil diameter and spherical aberration. Therefore, with a pupil diameter of 4 mm, the spherical aberration of children's eyes is estimated to be within the interquartile range of -0.05 to +0.08 μm. This is the interquartile range, and children with spherical aberration greater than +0.08 μm and children with spherical aberration less than -0.05 μm fall within the remaining interquartile range (i.e., half the number of children). In other words, nearly half of children have an absolute value of spherical aberration exceeding 0.08 μm. For the reasons stated above, the spherical aberration value assumed in this specification is an absolute value of 0.080 μm.

[0051] Figure 1C shows the distribution of the absolute value of astigmatism (vertical axis) in a horizontal cross-section passing through the center of the eye (distance from the center is indicated by the sign H: horizontal axis). According to Figure 1C, astigmatism of approximately 0.25 to 0.50 D (unit: diopters) occurs near the outer edge of the eye. Theoretically, if the second refractive region described above can cancel out this level of astigmatism, the problem of difficulty in focusing can be solved.

[0052] On the other hand, as shown in Figure 1B, local astigmatism has an axial direction along the radial direction of the eye. In other words, local astigmatism does not have a uniform axial direction. In this specification, "axial direction" means the direction in which the refractive power is maximum or minimum in a 360° orientation from a given position. In this specification, "axial direction" refers to the direction in which the refractive power is maximum when there is positive astigmatism, and to the direction in which the refractive power is minimum when there is negative astigmatism. However, in this specification, the sign of astigmatism is omitted in some qualitative discussions where it is not important whether it refers to maximum or minimum. Also, when it is written that astigmatism is increasing, it means that the absolute value of the amount of astigmatism is increasing.

[0053] The inventors investigated a configuration to compensate for localized astigmatism in the eye. Prior to this investigation, various tests were conducted.

[0054] Figure 2A is a graph that assumes a pupil with zero spherical aberration and a second refractive region with no aberration (spherical), with the vertical axis being VSOTF (Visual Strehl ratio based on OTF) and the horizontal axis being the amount of defocus (unit: D (diopter), zero being the retinal position). In this specification, the defocus amount on the horizontal axis represents the area in front of the retina (the side of the object being viewed) when negative, and the area behind the retina when positive.

[0055] VSOTF is a scalar quantity that takes into account contrast sensitivity characteristics thought to be due to retinal structure or the nervous system. VSOTF is the sum of the real parts of OTF weighted considering the sensitivity characteristics of the eye at each spatial frequency. The specific formula is as follows:

number

[0056] OTF is a measure used to evaluate lens performance. It is a complex numerical index that represents how faithfully the contrast of an object being viewed can be reproduced on the image plane, expressed as a spatial frequency characteristic. A large absolute value of OTF means that the contrast perceived by the wearer when viewing an object through the lens is high, and a small OTF deviation means that the positional displacement of the image is small. A large VSOTF value, which is the weighted sum of OTFs, means that there is less blurring and smudging of the image and a high degree of energy concentration.

[0057] Regarding VSOTF, it is described in the following document: "Thibos LN, Hong X, Bradley A, Applegate RA. Accuracy and precision of objective refraction from wavefront aberrations. J Vis. 2004 Apr 23;4(4):329-51.", and therefore, an explanation will be omitted here.

[0058] Figure 2B is a graph similar to Figure 2A, but it assumes a pupil with a spherical aberration of an absolute value of 0.080 μm and a second refractive region (spherical shape) with no aberration.

[0059] As shown in Figure 2A, the contrast is maximized when the horizontal axis (defocus amount) is zero due to the first refractive region (base region). The contrast is maximized near -4.0D on the horizontal axis (defocus amount) due to the second refractive region. When the wearer of the spectacle lenses perceives the light concentration that brings about this maximum contrast, the increase in eyeball length is suppressed, leading to the suppression of myopia progression. The first refractive region (base region) can be the region that possesses the prescribed refractive power.

[0060] On the other hand, the wearer perceives light focusing relatively, according to the Weber-Fechner law. What is important is not the absolute value of the maximum contrast, but rather the difference between the maximum contrast value due to the second refractive region and the low contrast (minimum value) between that maximum value and the maximum value. The arrows in the figure indicate this difference, and this difference will hereafter be called the "contrast ratio." In each figure in Figure 2, the contrast ratio is expressed as the value of maximum value / minimum value.

[0061] As shown in Figure 2B, due to spherical aberration in the eye, the contrast ratio is lower compared to Figure 2A.

[0062] However, as shown in Figure 1B, local astigmatism has an axial direction along the radial direction of the eye. In other words, local astigmatism does not have a single axial direction (for example, the horizontal direction). Even if astigmatism is introduced in the second refractive region in a single axial direction, it cannot cancel out all of the local astigmatism of the eye, and if it can, it can only cancel out a portion of it. To give a specific example, even if astigmatism with the axial direction to the right towards the wearer is uniformly introduced in the second refractive region, it will only cancel out the local astigmatism of the eye that has an axial direction in the vertical direction.

[0063] Meanwhile, the inventors have been investigating the significance of canceling out local astigmatism in certain areas of the distribution of local astigmatism in the eye.

[0064] Figure 2C is a graph similar to Figure 2A, but assumes a pupil with a spherical aberration of an absolute value of 0.080 μm and a second refractive region with aberration. Detailed test conditions will be explained in the Examples section below. In Figure 2C, the second refractive region with aberration has negative astigmatism, and the absolute value of this astigmatism (hereinafter also referred to as "amount of astigmatism"; unless otherwise specified, the sign of astigmatism is negative) is 0.40D. The surface shape of the second refractive region is a toric surface with an axial direction in the circumferential direction, and in plan view, it is set to be an elongated ellipse along the circumferential direction.

[0065] Figure 3A is a diagram comparing the size of the spectacle lens (right figure) and the size of the pupil (lower left figure) related to Figure 2C, and is an explanatory diagram in which the axis direction of the astigmatism provided in each second refractive region is indicated by a white arrow. The dimensional ratio of the second refractive region to the entire spectacle lens in each explanatory diagram of this application is not necessarily the actual dimensional ratio, but rather a dimensional ratio intended to illustrate an overview of one aspect of the present invention. Figure 3B is an explanatory diagram of the spectacle lens related to Figure 2C (left figure), and an enlarged explanatory diagram (right figure) showing the axis direction of astigmatism (white arrows) in each second refractive region of the spectacle lens related to Figure 2C and the axis direction of astigmatism (hatched arrows) of the eye. In this enlarged explanatory diagram, local astigmatism is canceled out near the upper and lower outer edges.

[0066] Although the contrast ratio should decrease due to spherical aberration in the eye, the second refractive region described above allows the contrast ratio to be maintained at a level comparable to that of Figure 2A, as shown in Figure 2C. In other words, as shown in the right-hand figure of Figure 3B, it was found that the decrease in the contrast ratio can be suppressed by canceling out local astigmatism in a portion of the eye's distribution.

[0067] In this specification, "cancellation" refers to the reduction in the absolute value of negative astigmatism near the outer edge of the eye by the second refractive region (hereinafter referred to as the buffer region) to 0.12D or less (preferably 0.10D or less, and even more preferably 0.05D or less) when light enters the wearer's pupil.

[0068] In this specification, "toric surface" includes the toric shape itself, as well as surfaces that are aspheric in shape (composite surfaces of toric and aspheric surfaces). In this specification, "toric surface" is composed of aspheric surfaces whose curvature changes with distance from the center.

[0069] Based on this knowledge, one embodiment of the present invention is an eyeglass lens.

[0070] Furthermore, to manufacture these eyeglass lenses, it is preferable to obtain the lens base material by using molding with a mold. The inventors have found that by performing lathe machining with appropriate control on the mold used for molding, the shape of the eyeglass lens, which is one aspect of the present invention, can be ideally realized.

[0071] Based on the above findings, the following embodiment of the present invention was created.

[0072] <Eyeglass Lenses> An eyeglass lens according to one aspect of the present invention has the following configuration. "A base region 3b that directs a light beam entering from the object-side surface, exits from the eye-side surface, enters the wearer's pupil, and focuses onto the retina, A retinal non-focusing region 3a is created in which a light beam incident from the object side is emitted from the eyeball side, while the light beam incident in the wearer's pupil is not focused onto the retina. It has a functional area that has, At least a portion of the non-focusing region 3a on the retina is a buffer region that cancels out localized negative astigmatism caused by spherical aberration of the eye at a portion of the distribution of said astigmatism. The surface shape of the buffer region is a toric surface with an axial direction in the circumferential direction, and when viewed from above, it has an elongated shape along the circumferential direction; this is an eyeglass lens.

[0073] As described above, it is not possible to completely cancel out all of the local astigmatism of the eye, and even if only a portion is canceled out, it is still possible to suppress the decrease in the contrast ratio. As a result, the spectacle lens according to one aspect of the present invention can reduce the influence of spherical aberration of the eye on the effect of suppressing or mitigating the progression of refractive errors.

[0074] In this specification, unless otherwise specified, the "(surface) shape" of an eyeglass lens refers to the shape of the surface of a film formed on a lens substrate when the eyeglass lens is constructed by forming a film on the lens substrate, and to the shape of the surface of the lens substrate when the eyeglass lens is the lens substrate itself.

[0075] In a planar view of the functional region, any non-focusing retinal region 3a within a band-shaped region consisting of a collection of 4mm diameter circles whose centers pass through a predetermined range of at least one diameter extending from the center of the lens may be considered a buffer region. For example, any non-focusing retinal region 3a within the dashed line enclosure in Figure 3A may be considered a buffer region. In other words, any non-focusing retinal region 3a within the dashed line enclosure in Figure 3A may have astigmatism (amount 0.25 to 0.50 D) with the circumferential direction as the axial direction. To put it another way, non-focusing retinal regions 3a above the dashed line enclosure in Figure 3A may not have astigmatism (i.e., be spherical) or, if they do, may have astigmatism of less than 0.25 D.

[0076] There are no limitations to the "predetermined range of at least one diameter extending from the center of the lens," and it may extend from the end closest to the center of the lens to the end furthest from the center in the functional region.

[0077] Furthermore, not just for one diameter, but within a predetermined range for all diameters, the non-converging retinal regions 3a within the band-shaped region may all be buffer regions. On the other hand, buffer regions may be omitted within the band-shaped region for some diameters. Spectacle lenses obtained by film deposition using the dip method described later fall under this example.

[0078] Furthermore, within any circle with a diameter of 4 mm within the band-shaped region, at least three buffer regions may be distributed and arranged in a dispersed manner.

[0079] In other words, while the buffer regions are concentrated in at least one band-shaped region extending from the center of the lens, they are also dispersed, making it easier to cancel out localized negative astigmatism in any part of the eye where such astigmatism exists.

[0080] The above distribution may also be defined as follows. The dispersion of the buffer regions may be such that both the first interval α, which is the length of the line segment connecting the centers of two buffer regions, and the second interval β, which is the distance between the center of the other buffer region closest to the line segment and whose center lies on the normal to the line segment, are less than 2 mm. The following figures illustrate examples of cases where the dispersion requirement is met and cases where it is not.

[0081] Figure 4A is an explanatory diagram showing the arrangement of a second refractive region that satisfies the dispersion requirements defined in one aspect of the present invention. Figure 4B is an explanatory diagram showing the arrangement of a second refractive region that does not satisfy the dispersion requirements defined in one aspect of the present invention.

[0082] The non-focusing region 3a on the retina may have a shape that protrudes from the base region 3b. In other words, the non-focusing region 3a on the retina may be a convex region. In that case, the non-focusing region 3a on the retina will have a myopia progression suppression effect.

[0083] An eyeglass lens may comprise a lens substrate and a laminated film provided to cover the lens substrate. The lens substrate is The base region 3b is based on the first refractive region of the substrate, The base material second refractive region that forms the basis of the non-focusing region 3a on the retina, It has, The surface shape of the second refractive region of the substrate that forms the basis of the buffer region is a toric surface having an axial direction in the circumferential direction, and may also be elongated in the circumferential direction when viewed from above.

[0084] In other words, the base region 3b, the retinal non-focusing region 3a, and the region that will form the basis of the buffer region may be formed at the lens substrate stage.

[0085] Even if a laminated film is provided so as to cover the lens substrate, the outermost surface shape can be obtained that conforms to the surface shape of the lens substrate to some extent, and as a result, it is possible to obtain the configuration of an eyeglass lens according to one aspect of the present invention. For this reason, the second refractive region of the substrate may have a shape that protrudes from the first refractive region of the substrate.

[0086] The above definitions of the band-shaped region and dispersion defined for eyeglass lenses may also be applied to the lens substrate. Specifically, this is as follows:

[0087] In a plan view of the lens substrate, the surface shape of the second refractive region of the substrate within a band-shaped region consisting of a collection of circles with a diameter of 4 mm, where the centers of the circles pass through a predetermined range of at least one diameter extending from the center of the lens, is a toric surface having an axial direction in the circumferential direction, and may be elongated in the circumferential direction when viewed in plan. Furthermore, at least three second refractive regions of the substrate may be dispersed within any 4 mm diameter circle within the band-shaped region.

[0088] The dispersion of the second refractive region of the substrate may be such that both the third interval, which is the length of the line segment connecting the centers of the two second refractive regions of the substrate, and the fourth interval, which is the distance between the line segment and the center of another second refractive region of the substrate that is closest to the line segment and whose center lies on the normal to the line segment, are less than 2 mm.

[0089] <Manufacturing method for eyeglass lenses> The following describes a method for manufacturing eyeglass lenses according to one aspect of the present invention, and then discusses preferred examples and variations of eyeglass lenses. Detailed information regarding the lens substrate material and other aspects will be provided later.

[0090] In a method for manufacturing eyeglass lenses according to one aspect of the present invention, A turning process is performed to machine the mold on a lathe so that the surface shape of the second refractive region of the lens substrate, which forms the basis of the buffer region, is a toric surface with an axial direction in the circumferential direction, and when viewed from above, it has an elongated shape along the circumferential direction. A molding process in which a lens substrate is formed using a mold after lathe machining, It has.

[0091] (1. Turning process for the mold) In one aspect of the present invention, a lens substrate is manufactured by injection molding using a mold. In order to obtain a lens substrate having the surface shape described above, the mold needs to be processed to produce a surface shape that is an inverse of the said shape. For example, if the second refractive region of the substrate is a convex region, the mold needs to form a concave region.

[0092] The mold may be subjected to a turning process so that the second refractive region of the base material is formed as a number of independent island-like regions.

[0093] As mentioned earlier, the surface shape of the second refractive region (convex region) of the substrate, which forms the basis of the buffer region, must be a toric surface with an axial direction in the circumferential direction. Therefore, it is also necessary to form a concave region of the toric surface in the mold.

[0094] One of the key features of the method for manufacturing eyeglass lenses according to one aspect of the present invention is that a region corresponding to the second refractive region of the base material is formed in the mold using lathe machining.

[0095] In one embodiment of the present invention, a turning process involves repeatedly bringing a cutting tool called a cutting tool into contact with the mold for a predetermined time while the mold is rotating at high speed, thereby carving a predetermined shape into the mold. When forming a concave region of a toric surface in the mold, the radial and circumferential curves in the concave region of the mold can be arbitrarily set by the tip shape of the cutting tool, the rotation speed of the mold, the contact time of the cutting tool, etc. This means that the amount of astigmatism caused by the toric surface in the concave region of the mold can be arbitrarily set. Furthermore, it is also possible to increase the amount of astigmatism by increasing the rotation speed of the mold during turning.

[0096] In any case, the axial direction (maximum refractive force or minimum refractive force) of the astigmatism caused by the second refractive region (convex region) of the substrate obtained by this concave region is circumferential.

[0097] Furthermore, as described above, when forming a concave region of the toric surface in the mold, turning is employed, making it easier to machine the concave region in a long length along the circumferential direction (i.e., the direction of rotation of the mold). Being long in the circumferential direction means that negative astigmatism is present with the circumferential direction as the axis. The further away from the center of rotation of the turning (i.e., the closer to the outer edge of the mold), the easier it is to machine it in a long length. This means that it is easier to produce a long second refractive region (convex region) of the base material obtained by the concave region.

[0098] Furthermore, as mentioned above, the amount of astigmatism can be set arbitrarily, making it a shape that easily induces astigmatism. In addition, the elongated shape in the circumferential direction means that, compared to a perfectly circular buffering area in plan view, the longer buffering area at the spectacle lens stage makes it easier for light to enter the 4mm diameter pupil, thereby increasing the possibility of canceling out the eye's astigmatism.

[0099] The mold may have multiple concave regions of the same shape, or all concave regions may be of the same shape. Furthermore, considering the above characteristics of lathe machining, the concave regions may be made longer in the circumferential direction as they approach the outer edge of the mold. The concave region near the center of rotation of the mold may be made spherical so that the non-converging region 3a on the retina above the dashed line in Figure 3A becomes spherical.

[0100] Furthermore, it is preferable that the size of the resulting retinal non-focused region 3a satisfies the following requirements. We focus on the relative frequency of the non-converging retinal region 3a with respect to the base region 3b. Let L (in units: D) be the absolute value of this relative frequency. If the non-converging retinal region 3a is elongated in the circumferential direction, astigmatism of 0.25 to 0.50 D can be introduced if the ratio M of the length of the long side (circumferential length in planar view) to the length of the short side (radial length in planar view) of the non-converging retinal region 3a satisfies the following formula. 0.25 <L-L / M 2 <0.50 It is more likely that L will be between 3.00 and 5.00D, in which case M will be around 1.025 to 1.085.

[0101] (2. Molding process for forming the lens substrate) The lens substrate is formed using the mold created after the above lathe machining process. There are no limitations on the molding method; injection molding can be used.

[0102] The resulting lens substrate also preferably satisfies the following requirements. The base material second refractive region that forms the basis of the non-focusing region 3a on the retina includes at least base material second refractive regions a1 and b1. At least the second refractive region b1 of the substrate is the base of the buffer region, In a planar view, the second refractive region b1 of the substrate, which is further from the lens center, may have a longer shape along the circumferential direction compared to the second refractive region a1 of the substrate, which is closer to the lens center. The above regulations apply to eyeglass lens 1 as follows: "The retinal non-focusing region 3a includes at least retinal non-focusing regions A1 and B1, At least the non-converging region B1 on the retina is a buffer region, In a planar view, the non-focusing region B1 on the retina, which is further from the lens center, has a longer shape along the circumferential direction compared to the non-focusing region A1 on the retina, which is closer to the lens center.

[0103] Furthermore, in a planar view, the further away from the center of the lens the second refractive region of the substrate becomes, the longer its shape along the circumferential direction, and it may also become a toric surface that is far from a sphere.

[0104] (3.Lamination process) A lamination process may be performed in which a laminated film is formed to cover the lens substrate obtained using a mold after lathe machining.

[0105] Examples of multilayer film types will be shown later, but depending on the manufacturing method used for each film, it is possible to change the amount of astigmatism present in the buffer regions at the spectacle lens stage for each buffer region arranged circumferentially on the spectacle lens.

[0106] For example, at least one of the laminated films (here, a hard coat film is assumed) may be formed by a dipping method using a dipping solution having predetermined physical properties, thereby causing the thickness of the film to be unevenly distributed around the second refractive region of the substrate, and causing the astigmatism values ​​to differ depending on the circumferential position in each buffer region.

[0107] For details on the dip method, please refer to publication WO2021 / 131457.

[0108] As shown in Figure 7 of the publication, when the center of the second refractive region (convex region) of the lens substrate is arranged in a hexagonal configuration, when a film is deposited using the dip method under predetermined conditions, the maximum film thickness is obtained at clockwise rotation angles of 90° (3 o'clock direction) and 270° (9 o'clock direction) from the 12 o'clock direction, which is the pulling direction of the dip method (in this specification, the +X direction and -X direction, i.e., the horizontal direction, left and right direction), and the minimum film thickness is obtained at clockwise rotation angles of 180° (6 o'clock direction) and 360° (12 o'clock direction) from the 12 o'clock direction (in this specification, the -Y direction and +Y direction, i.e., the vertical direction, up and down direction).

[0109] The formation of maximum and minimum film thickness areas in and around the second refractive region of the lens substrate means that the amount of astigmatism in the buffer region of the final spectacle lens will differ from the amount of astigmatism in the second refractive region of the lens substrate. Moreover, due to the adoption of the dip method, a uniform change in the amount of astigmatism in the axial direction (in this case, the horizontal direction) is applied to all second refractive regions of the lens substrate.

[0110] Figure 5A is the same diagram as the right-hand diagram in Figure 3A, and is an explanatory diagram in which the axial direction of the astigmatism provided in each second refractive region is indicated by a white arrow. Figure 5B is an explanatory diagram showing the axial direction of astigmatism present in the second refractive region of each substrate, indicated by white arrows, when a film is deposited using the dip method under predetermined conditions. Figure 5C is an explanatory diagram showing the axis direction of astigmatism in each second refractive region of the spectacle lens shown in Figure 5A, and the amount of astigmatism, indicated by the length of the white arrow, after the dip method is used to deposit the film.

[0111] As shown in Figure 5B, when the above dip method is employed, the film thickness is maximized in the left-right direction of the second refractive region of each substrate, and conversely, the film thickness is minimized in the up-down direction, which is the pulling direction. As a result, astigmatism with an axial direction (direction of maximum refractive force) in the horizontal direction tends to be present in the second refractive region of each substrate.

[0112] As shown in Figure 5A, each substrate's second refractive region has a predetermined amount of astigmatism with the circumferential direction as the axial direction. The astigmatism brought about by the film deposition using the dip method and the astigmatism already present in each substrate's second refractive region are combined. As a result, a second refractive region (i.e., a region where spherical aberration can be eliminated) with astigmatism in both the axial direction and in a given amount, as shown in Figure 5C, is obtained. The configuration shown in Figure 5C may also be expressed as follows. "Among the retinal non-focusing regions 3a on each circumference, there exist two lines that have a relationship in which the absolute value of astigmatism is large for the retinal non-focusing region 3a that lies on a line passing through the center of the lens (the vertical line in Figure 5C), and the absolute value of astigmatism is small for the retinal non-focusing region 3a that lies on a line perpendicular to that line and passing through the center of the lens (the horizontal line in Figure 5C)."

[0113] To illustrate with specific numerical examples, in Figure 5A, all substrate second refractive regions are toric surfaces with an axial direction in the circumferential direction, and in plan view, they are made to have an elongated shape along the circumferential direction, thereby providing the substrate second refractive region with an astigmatism of -0.20D with the circumferential direction as the axial direction. Then, in Figure 5B, by using the dip method for film deposition, an additional astigmatism of -0.20D with the left-right direction as the axial direction is added. As a result, as shown in Figure 5C, a second refractive region (i.e., a region where spherical aberration can be eliminated) is obtained in the vertical direction from the lens center of the spectacle lens where the amount of astigmatism is maximum. On the other hand, a second refractive region is obtained in the left-right direction from the lens center of the spectacle lens where the amount of astigmatism is minimum (zero in Figure 5C). The reason for this is that, as shown in Figure 5A, in the substrate second refractive region located in the left-right direction from the lens center of the spectacle lens, the circumferential direction is vertical, and it cancels out with the left-right astigmatism in Figure 5B. In this context, "maximum" and "minimum" astigmatism refer to the maximum and minimum astigmatism in the second refractive region when viewed in the circumferential direction at a predetermined diameter, or to the maximum and minimum average astigmatism within the aforementioned band-shaped region in the entire rotational direction from the lens center.

[0114] To achieve cancellation of these astigmatisms, it is preferable to make the astigmatism introduced during the turning process and the astigmatism introduced by the dip method during the lamination process equal in amount. Specifically, it is preferable that the difference in the amount of the two astigmatisms is 0.125D or less (preferably 0.12D or 0.06D or less).

[0115] By employing the dip deposition method, the functional region can be divided into a region where spherical aberration with high astigmatism can be eliminated, a region where spherical aberration with low astigmatism can be eliminated, and a second refractive region where astigmatism is zero, as shown in Figure 5C.

[0116] This division may also be made using a fan-shaped region enclosed by two diameters extending from the center of the lens. In Figure 5C, the range of clockwise rotation angles from the lens center of at least -15 to +15°, encompassing the 12 o'clock direction, and the range of rotation angles of 165 to 195°, encompassing the 6 o'clock direction, may be defined as the region where high astigmatism in spherical aberration can be eliminated. On the other hand, the range of clockwise rotation angles from the lens center of at least 75 to 105°, encompassing the 3 o'clock direction, and the range of rotation angles of 255 to 285°, encompassing the 9 o'clock direction, may be set as the second refractive region where astigmatism is zero. The fan-shaped region that is neither of the above may be defined as the region where spherical aberration can be eliminated with low astigmatism. There is no limit to the amount of astigmatism in the retinal non-focusing region 3a between the area where the absolute value of astigmatism is large (up and down lines in Figure 5C) and the area where it is small (left and right lines in Figure 5C). For example, it may monotonically decrease along the circumferential direction from the area with a large absolute value to the area with a small absolute value, or the absolute value may decrease while repeatedly decreasing and increasing.

[0117] The spectacle lens shown in Figure 5C can solve, or replace, the problem of suppressing or reducing the progression of refractive errors, regardless of the degree of spherical aberration in the eye. This will be described in detail below.

[0118] Figure 6A is the same diagram as the right-hand diagram in Figure 3A, and is an explanatory diagram that uses arrows to indicate the positions that the line of sight frequently passes through when wearing eyeglass lenses. Figure 6B is the same diagram as Figure 5C, and is an explanatory diagram showing how the orientation of the spectacle lens was determined so that the buffering area where astigmatism is maximized is positioned at the location where the line of sight frequently passes, in order to accommodate a child whose spherical aberration of the eye is an absolute value of 0.080 μm. Figure 6C is an explanatory diagram showing how the orientation of the spectacle lens was determined so that the second refractive region, which has zero astigmatism, is positioned at a location frequently passed through by the line of sight, in order to accommodate children whose eyes have zero spherical aberration.

[0119] The degree of spherical aberration in the eye varies from person to person (primarily children). If all secondary refractive regions of an eyeglass lens were designed to have astigmatism, a child with zero spherical aberration would be exposed to unwanted astigmatism when wearing such lenses. Therefore, such eyeglass lenses would only be available to children with some degree of spherical aberration.

[0120] On the other hand, with the spectacle lens shown in Figure 5C, there is a second refractive region where astigmatism is zero in the radial direction. For example, when a child with zero spherical aberration in their eye wears this spectacle lens, the second refractive region with zero astigmatism is positioned where the line of sight frequently passes. By utilizing this feature and determining the orientation of the spectacle lens according to the degree of spherical aberration in the wearer's eye, as shown in Figures 6B and 6C, it is possible to achieve the same refractive error progression suppression or reduction effect regardless of the degree of spherical aberration in the eye. In other words, by creating one type of spectacle lens in which the second refractive region (buffer region) has astigmatism as shown in Figure 5C, it is possible to provide spectacle lenses to wearers regardless of the degree of spherical aberration in their eye. This makes spectacle lenses more versatile.

[0121] When addressing the issues described in the paragraph above, spherical aberration will naturally not be canceled out in children whose eyes have zero spherical aberration. For this reason, although this specification refers to such a second refractive region as a buffer region, it may also be called a region where spherical aberration can be canceled out.

[0122] In determining the orientation of the above-mentioned spectacle lens, the process may further include a marking step in which marks are placed on the spectacle lens to indicate that the value of astigmatism differs depending on the circumferential position in each buffer region. This information concerns which radial direction, viewed from the center of the lens, has a second refractive region (buffer region) with large astigmatism, and / or a second refractive region with small (or zero) astigmatism. There are no limitations on the type or size of the marks; as long as this information, i.e., the orientation, is known, it is sufficient.

[0123] The technical concept of the present invention is also reflected in eyeglasses in which the peripheral edge of the above-mentioned spectacle lens 1 is cut based on a predetermined frame shape and fitted into the frame. In particular, when handling spectacle lenses bearing the above-mentioned mark, the technical concept of the present invention is also reflected in the method of manufacturing eyeglasses in which the orientation of the spectacle lens is determined according to the magnitude of the spherical aberration of the wearer's eye and then fitted into the frame. In this case, if the above-mentioned mark is placed on the lens at a position corresponding to the outside of the frame (hereinafter simply referred to as the frame), the mark will not encroach on the area used as a lens (inside the frame).

[0124] There are no restrictions on the type or shape of the frame; it can be full-rim, half-rim, under-rim, or rimless.

[0125] Furthermore, there is evidence suggesting that the greater the absolute difference between the astigmatism of light incident on the upper part of the retina (i.e., above the macula, the central region) and the astigmatism of light incident on the lower part of the retina (i.e., below the macula), the more likely it is that myopia progression will be suppressed in that person.

[0126] Considering this finding, if we define V as the absolute value of the difference between the astigmatism of light incident on the upper retina and the astigmatism of light incident on the lower retina when uncorrected, and V' as the absolute value of the difference between the astigmatism of light passing through the non-focusing region 3a on the retina and the astigmatism of light incident on the lower retina when wearing eyeglass lenses, then it is expected that the greater the magnification and enhancement of V' compared to V, the greater the myopia suppression effect of eyeglass lenses.

[0127] Therefore, when framing the lens of the above embodiment, which has different astigmatisms depending on its position on the lens, it is preferable to frame it in an orientation such that V' is greater than V, as described above. This feature is both an invention of a method for designing eyeglass lenses and an invention of a method for manufacturing eyeglasses, in which the framing direction is determined to be such that V' is greater than V.

[0128] Furthermore, to assist in the framing process, a compass mark indicating the direction may be provided at one of the positions on the eyeglass lens (preferably outside the frame).

[0129] When framing the glasses, the eyeglasses may be manufactured by referring to the directional mark described in the paragraph above. In this case, the eyeglass lens manufacturing method described above may be applied. In this case, the directional mark may be included in the marks handled in the marking process described above.

[0130] Furthermore, characteristic values ​​regarding the difference in astigmatism between the upper and lower parts of the human retina may be obtained by measuring the wearer's eye, or numerical values ​​obtained beforehand statistically or academically may be used.

[0131] The technical concept of the present invention is also reflected in the mold used in the lathe machining process and the machining method (manufacturing method) thereof. Furthermore, there are no limitations on the material of the mold used in the manufacturing method of eyeglass lenses according to one embodiment of the present invention; it may be a metal mold or a glass mold.

[0132] The explanation described the case where the dip method is used in the lamination process, but other methods may be used in conjunction with or instead of the dip method. For example, the spin coating method may be used. The spin coating method tends to result in a more uniform film thickness, which is useful when it is desired to maintain the shape of the second refractive region of the substrate even at the outermost surface of the spectacle lens. Furthermore, film deposition using the vacuum deposition method tends to result in an even more uniform film thickness. A hard coat film may be deposited using the dip method, and then an anti-reflective film may be deposited on the surface of the hard coat film by vacuum deposition. In addition, a protective film (such as a water-repellent or hydrophilic anti-fouling film or anti-fogging film) may be provided to cover the anti-reflective film, or any film may be formed between the lens substrate and the protective film.

[0133] When employing the dip method, it is possible to increase the amount of astigmatism by increasing the pull-up speed. When using the spin coating method, the film thickness is usually uniform, but it is also possible to slightly increase the amount of astigmatism by increasing the rotation speed.

[0134] The projection distance of the non-focusing region 3a on the retina from the base region 3b may be greater than 1.00 μm. Similarly, the projection distance of the second refractive region of the substrate from the base region 3b may be greater than 1.00 μm. If the second refractive region of the substrate has a size of this magnitude, uneven distribution of film thickness can be effectively achieved when film deposition is performed using the dip method. An example of the upper limit of this projection distance is 2.00 μm. In the turning process, the portion of the mold corresponding to the second refractive region of the substrate may be recessed more than the portion corresponding to the first refractive region of the substrate, and the recess distance may be greater than 1.00 μm, with an example of the upper limit being 2.00 μm.

[0135] The "protrusion distance from the base region 3b" is also called the "sag amount." The sag amount refers to the maximum distance of the retinal non-converging region 3a from the tangent plane of the base region 3b when the non-converging region 3a is absent (for example, the distance from the tangent plane to the vertex of the convex region).

[0136] The explanations so far have discussed the effects of spherical aberration of the eye on and near-axial light beams. On the other hand, the inventors have found that even with light beams where the optical power and astigmatism characteristics off-axis differ from those on-axis, the intended optical characteristics cannot be obtained due to ocular aberration, particularly spherical aberration. More specifically, the inventors have found that the contrast of the focused light created at the point defocused from the retina due to the segmentation effect does not have sufficient intensity compared to the contrast of the non-focused area. One embodiment of the present invention solves this problem without increasing manufacturing costs.

[0137] However, the on-axial beam, which is less affected by astigmatism due to the angle of incidence to the eye, is more susceptible to the effects of spherical aberration and its cancellation. Therefore, it is more effective to apply sufficient astigmatism from the center of the lens or from the non-focusing region 3a on the retina near the central clear region.

[0138] <An example of eyeglass lens 1 (overview)> An outline of a specific example of the eyeglass lens 1 in one aspect of the present invention is described below.

[0139] An eyeglass lens according to one aspect of the present invention comprises a central clear region and a functional region.

[0140] The central clear region is the region including the center of the lens and / or the eye point, where the light beam incident from the object-side surface is directed out from the eye-side surface, enters the wearer's pupil, and converges on the retina. In other words, the central clear region consists of the base region 3b. The central clear region is a portion having a smooth surface shape that can realize the wearer's prescribed refractive power from a geometrical optical standpoint, and is, for example, a portion that is transparent in the visible light wavelength range.

[0141] The "eye point (EP)" is, for example, the position through which the line of sight passes when the wearer is looking straight ahead while wearing eyeglass lenses, and this example will be given hereafter. The eye point may also be the position through which the line of sight passes when the wearer views an object close to the wearer (so to speak, when viewing at close range), i.e., the near-seeing eye point. In one embodiment of the present invention, an example is given in which the geometric center of the eyeglass lens before it is fitted into a frame coincides with the eye point, coincides with the prism reference point, and coincides with the lens center. Hereafter, an example of an eyeglass lens according to one embodiment of the present invention will be given as an eyeglass lens before it is fitted into a frame, but the present invention is not limited to this embodiment.

[0142] The eye point can be identified by referring to a remark chart or centration chart issued by the lens manufacturer.

[0143] In one embodiment of the present invention, the central clear region enables the realization of prescription powers (spherical power, astigmatism power, astigmatism axis, etc.). This spherical power may be the power to be corrected when looking straight ahead (at a distance of approximately 1m to infinity) (for example, distance power, which will be used as an example hereafter), or it may be the power to be corrected when looking at an intermediate object (1m to 40cm) or a near object (40cm to 10cm).

[0144] Furthermore, the central clear region does not contain any configurations intended to suppress or reduce the progression of refractive errors (i.e., myopia progression suppression effect or hyperopia reduction effect) (e.g., convex region 3a and / or concave region, embedded structure, etc., which become non-converging regions 3a on the retina).

[0145] In one embodiment of the present invention, the central clear region (and the base region 3b within the functional region, and furthermore, the outer clear region) functions as a so-called fixed-focus lens.

[0146] Incidentally, the wearer's prescription data is printed on the lens bag of the eyeglass lenses. In other words, if the lens bag is present, it is possible to identify the eyeglass lenses as belonging to the wearer based on their prescription data. Furthermore, eyeglass lenses are usually sold as a set with a lens bag. Therefore, eyeglass lenses that come with a lens bag also reflect the technical concept of this invention, and the same applies to the set of lens bag and eyeglass lenses.

[0147] The functional region is an annular region in planar view that is adjacent to and surrounds the central clear region. The region of the functional region other than the base region 3b is the retinal non-converging region 3a.

[0148] For example, in cases where a convex region 3a is provided in an island-like manner, as in the second refractive region of Patent Document 1, while a first refractive region that realizes the prescription power (a base region 3b that performs the same function as the central clear region) is provided around the convex region, the annular region including the base region 3b and the convex region 3a is considered the functional region.

[0149] An eyeglass lens according to one aspect of the present invention comprises an annular outer clear region adjacent to and surrounding the functional region on the outer edge side of the eyeglass lens. The outer clear region causes the light beam incident from the object-side surface to exit from the eye-side surface, enter the wearer's pupil, and converge on the retina. In other words, the functional region is an annular region located between the outer clear region and the central clear region.

[0150] The shape of functional region 3 is not limited and may be ring-shaped in plan view. The ring may be circular, rectangular, elliptical, or a combination thereof on the inside (i.e., the boundary between the central clear region 2 and functional region 3) and / or on the outside (i.e., the boundary between the outer clear region 4 and functional region 3).

[0151] The spectacle lens 1 according to one aspect of the present invention may be a spectacle lens 1 after being fitted into a frame, and a part of the functional region 3 of the spectacle lens 1 may be in contact with the outer edge of the spectacle lens 1, while the other part of the functional region 3 may be in contact with the outer clear region 4. Furthermore, it is not prohibited to provide a retinal non-converging region 3a on the outer edge side of the outer clear region 4.

[0152] However, considering the need to easily obtain good visibility in the peripheral field of view, it is preferable that there is no configuration between the outer edge of the spectacle lens 1 and the functional area 3 that is intended to provide a myopia progression suppression effect or a hyperopia reduction effect. In other words, it is preferable that the entire area between the outer edge of the spectacle lens 1 and the functional area 3 is the outer clear area 4.

[0153] Furthermore, the functional region may be extended toward the center of the lens by filling the central clear region of the eyeglass lens 1 (for example, Figure 10 of Patent Document 1). However, considering that the line of sight frequently passes through the center of the lens, it is preferable to provide a central clear region, as in the eyeglass lens according to one embodiment of the present invention described above.

[0154] A characteristic aspect of the present invention is that the retinal non-focusing region 3a is concentrated within the functional region 3 of the entire spectacle lens 1. In other words, it is preferable that the retinal non-focusing region 3a is not provided in the outer clear region 4 on the outer edge side of the functional region 3 (preferably between the outer edge of the functional region 3 and the outer edge of the spectacle lens 1).

[0155] There are no limitations on the size and shape of the central clear area 2. One guideline for the lower limit of the central clear area 2's size is that it should be large enough to encompass a circle with a diameter of 5.00 mm centered on the lens center (eyepoint EP). One guideline for the upper limit of the central clear area 2's size is that it should fit within a circle with a diameter of 10.00 mm centered on the lens center. The minimum horizontal distance from the lens center to the edge of the central clear area 2 (or the minimum radius if the clear area is circular in plan view) may be 3.60 mm or less. The area of ​​the central clear area 2 is 80 mm². 2 The following is also possible: The shape of the central clear area 2 may be circular, rectangular, elliptical, etc., in plan view.

[0156] There are no limitations on the size and shape of functional region 3. One guideline for the lower limit of the size of functional region 3 is that it should be large enough to encompass a circumference with a diameter of 15 mm centered on the lens center. One guideline for the upper limit of the size of functional region 3 is that it should be large enough to encompass a circumference with a diameter of 50.00 mm centered on the lens center. The shape of functional region 3 is annular in plan view, and the ring may be circular, rectangular, elliptical, polygonal, or a combination thereof on the inside (i.e., the boundary between the central clear region 2 and functional region 3) and / or on the outside (i.e., the boundary between the outer clear region 4 and functional region 3).

[0157] For example, when a wearer is viewing something at close range, the interpupillary distance (PD) tends to decrease due to convergence. Therefore, in this case, the wearer's line of sight will pass through the area closer to the center (towards the nose) of the lens than the eye point.

[0158] Therefore, taking this point into consideration, it is also preferable to position the central clear area 2 so that it is shifted inward (towards the nose when worn) from the center of the lens 1 (for example, the geometric center). In this case, the center of the central clear area 2 will be at a position shifted towards the nose from the geometric center (or eye point) of the lens 1. In this specification, "center" refers to the center of a circle or ellipse, and to the center of gravity for other shapes.

[0159] In that case, it is also preferable that the multiple non-converging retinal regions 3a (and thus functional regions 3) designed and arranged according to the above embodiment are shifted nasally with respect to the lens center and are arranged asymmetrically within the region of lens 1.

[0160] Figure 7 is an explanatory diagram illustrating an example of the definition of the boundary between the functional region and the central clear region, and an explanatory diagram illustrating an example of the definition of the boundary between the functional region and the outer clear region.

[0161] The following is a preferred definition of the shape of the central side of the functional region 3 (i.e., the shape of the central side clear region 2).

[0162] In a planar view, the boundary line between the functional region 3 and the central clear region 2 may be defined as the envelope EL2 of the collection of all circles with a diameter of 4 mm that can circumscribe the non-converging retinal regions 3a within the functional region 3 on the central clear region 2 side without including other said non-converging retinal regions 3a. In this specification, each of these circles is also referred to as a clear pupil circle. The shape of the central clear region 2 may be defined as the "collection of clear pupil circles" rather than the envelope of the collection of clear pupil circles.

[0163] The following is a preferred definition of the shape of the outer edge of functional region 3 (i.e., the shape of functional region 3 on the outer clear region 4 side and the boundary between the two).

[0164] In planar view, the boundary line between the functional region 3 and the outer clear region 4 may be defined as the envelope EL1 of all circles with a diameter of 4 mm that can circumscribe the non-converging retinal region 3a within the functional region 3 on the outer clear region 4 side without including other said non-converging retinal regions 3a (definition of the outer edge of the functional region 3). Hereafter, the envelope will be used as an example, but the shape of the outer clear region 4 may be defined as a "collection of clear pupil circles" rather than the envelope of a collection of clear pupil circles. In other words, the outer clear region 4 may include the eye point EP and be composed of a collection of clear pupil circles. Furthermore, in the spectacle lens 1, the region other than the central clear region 2 and the outer clear region 4 may be defined as the functional region 3.

[0165] As a guideline, functional region 3 may be defined as not converging on the retina with 30% or more (or 40%, 50%, or 60%) of the light beam entering the wearer's pupil. A higher percentage is expected to result in greater myopia progression suppression or hyperopia reduction, but visibility will decrease. The percentage should be determined appropriately based on the balance between myopia progression suppression or hyperopia reduction and visibility.

[0166] Furthermore, in functional region 3, the area of ​​the non-converging region 3a on the retina in planar view may be defined as 30% or more (or 40% or more, 50% or more, or 60% or more) of the entire functional region 3. The upper limit may be, for example, 70%.

[0167] In a planar view of the functional region, there are no limitations on the predetermined range of at least one diameter extending from the center of the lens. For example, any non-converging retinal region 3a within the overall band-shaped region, which consists of a collection of circles with a diameter of 4 mm passing through the entire functional region (from the region near the center of the lens to the region near the outer edge of the lens), may be considered a buffer region. On the other hand, only a part of the predetermined range may be considered the band-shaped region. The band-shaped region may occupy 30% or more (or 40% or more, 50% or more, or 60% or more) of the area of ​​the overall band-shaped region.

[0168] In a planar view of the functional region, the above requirements apply to at least one diameter extending from the center of the lens. These requirements may be met for all diameters, or only for some diameters, as in the case where the film is deposited using the dip method described above.

[0169] <A specific example of eyeglass lens 1 (details)> A specific example of the eyeglass lens 1 in one aspect of the present invention is described below.

[0170] In functional region 3, an example of a configuration (retinal non-focusing region 3a) that exhibits a myopia progression suppression effect or a hyperopia reduction effect is the defocus region.

[0171] A defocus region is, from a geometrical optical standpoint, a region in which at least a portion is not focused to the focusing position of the base region 3b. A defocus region corresponds to the minute protrusion described in Patent Document 1. An eyeglass lens 1 according to one aspect of the present invention is a myopia progression suppressing lens, similar to the eyeglass lens described in Patent Document 1. Similar to the minute protrusion described in Patent Document 1, the multiple defocus regions according to one aspect of the present invention may be formed on at least one of the object-side surface and the eyeball-side surface of the eyeglass lens 1. In this specification, the case in which multiple defocus regions are provided only on the object-side surface of the eyeglass lens 1 is mainly illustrated. Hereafter, unless otherwise specified, the defocus region is illustrated as having a curved shape that protrudes toward the outside of the lens.

[0172] Preferably, more than half of the multiple defocus regions (all defocus regions within the functional region) are arranged in the same period when viewed from above. An example of a pattern with the same period is an equilateral triangle arrangement when viewed from above (the centers of the defocus regions are located at the vertices of an equilateral triangle net, a so-called honeycomb structure). Preferably, this is 80% or more, more preferably 90% or more, and even more preferably 95% or more. Hereafter, preferred examples of "more than half of all defocus regions within the functional region (or more than 80%)" will be listed in the same order of preference as above: 80% or more, 90% or more, and 95% or more, and the repetition will be omitted.

[0173] The defocus region may be spherical, aspherical, toric, or a combination of these (for example, the center of each defocus region may be spherical, while the surrounding area outside the center may be aspherical). At least the buffer region must be toric.

[0174] A boundary between the central and peripheral parts of the defocus region (or convex region 3a) may be provided at a point that is 1 / 3 to 2 / 3 of the radius in a plan view. However, it is preferable that at least the central part of the defocus region (or convex region 3a) has a convex curved shape that protrudes outward from the lens. Furthermore, since it is preferable that more than half of the multiple defocus regions (all defocus regions within the functional region) are arranged in the same period in a plan view, it is preferable that the defocus regions other than the buffer regions are spherical. Of course, all defocus regions may also be buffer regions, in which case all defocus regions will have a toric surface shape.

[0175] Each defocus region is configured, for example, as follows. The diameter of the defocus region in plan view is preferably around 0.6 to 2.0 mm. The surface area of ​​each region is 0.50 to 3.14 mm. 2 It may be of a certain degree. The radius of curvature of the convex region 3a is spherical, with a radius of curvature of 50 to 250 mm, preferably about 86 mm.

[0176] While there are no specific numerical limits on the defocus power in each defocus region, it is preferable that, for example, the minimum defocus power produced by the defocus region on the spectacle lens 1 is within the range of 0.50 to 4.50 D, and the maximum value is within the range of 3.00 to 10.00 D. The difference between the maximum and minimum values ​​is preferably within the range of 1.00 to 5.00 D.

[0177] "Defocus power" refers to the difference between the refractive power of each defocused region and the refractive power of the parts outside each defocused region. In other words, "defocus power" is the difference obtained by subtracting the refractive power of the base portion from the average value of the minimum and maximum refractive powers at a predetermined point in the defocused region. In this specification, the case in which the defocused region is a convex region 3a is given as an example.

[0178] In this specification, "refractive force" refers to the average refractive force, which is the average value of the refractive force in the direction in which the refractive force is minimum and the refractive force in the direction in which the refractive force is maximum (perpendicular to that direction).

[0179] The arrangement of the defocus area is not particularly limited and can be determined from perspectives such as visibility from outside the defocus area, design enhancement by the defocus area, and refractive power adjustment by the defocus area. The defocus area is an example of a non-focusing area 3a on the retina, in which the light beam is not focused on the retina but is focused on the front side of the retina (-Z direction side).

[0180] In the functional region 3 arranged around the central clear region 2 of the spectacle lens 1, approximately circular defocus regions may be arranged in an island-like manner (i.e., separated from each other without being adjacent) at equal intervals in the circumferential and radial directions. As an example of the arrangement of defocus regions in plan view, each convex region 3a is independently and discretely arranged such that its center becomes the vertex of an equilateral triangle (the center of each defocus region is located at the vertices of a honeycomb structure: hexagonal arrangement). In this case, the spacing between defocus regions may be 1.0 to 2.0 mm. Furthermore, the number of defocus regions (and thus non-converging regions 3a on the retina) may be 10 to 200.

[0181] The lens substrate is formed from a thermosetting resin material such as thiourethane, allyl, acrylic, or epithio. However, other resin materials that can achieve the desired refractive index may be selected as the resin material constituting the lens substrate. Alternatively, an inorganic glass lens substrate may be used instead of a resin material.

[0182] The hard coat film is formed, for example, using a thermoplastic resin or a UV-curable resin. The hard coat film can be formed by immersing the lens substrate in a hard coat solution or by using a spin coat, etc. By forming such a hard coat film, the durability of the spectacle lens 1 can be improved.

[0183] The anti-reflective coating is formed by vacuum deposition of an anti-reflective agent such as ZrO2, MgF2, or Al2O3. The formation of such an anti-reflective coating improves the visibility of the image seen through the eyeglass lens 1.

[0184] As described above, multiple defocus regions are formed on the object-facing surface of the lens substrate. Therefore, when a hard coat film and an anti-reflective film are applied to that surface, multiple defocus regions are also formed by the hard coat film and the anti-reflective film, following the defocus regions on the lens substrate.

[0185] The film thickness formed by the lamination process may be, for example, in the range of 0.1 to 100 μm (preferably 0.5 to 5.0 μm, more preferably 1.0 to 3.0 μm). However, the film thickness is determined according to the function required of the film and is not limited to the range exemplified above.

[0186] The technical scope of the present invention is not limited to the embodiments described above, and includes various modified and improved forms to the extent that specific effects can be obtained by the constituent elements of the invention or combinations thereof.

[0187] In one aspect of the present invention, the astigmatism distribution shown in Figure 5C is achieved by combining the astigmatism present in the second refractive region of the lens substrate with the astigmatism present by the film deposition using the dip method, but the method of achievement is not limited to this. For example, the surface shape of the second refractive region of the lens substrate is set to produce the astigmatism distribution shown in Figure 5C. Specifically, a concave region is processed into such a shape during the turning process of the mold. For film deposition on the lens substrate, a spin coating method that results in a relatively uniform film thickness or a vacuum deposition method that results in a uniform film thickness may be employed. In addition, with the dip method, the film thickness can be made relatively uniform by lowering the pulling speed. [Examples]

[0188] The present invention will now be described in detail with reference to examples. The present invention is not limited to the following examples.

[0189] <Reference Example 1> The following spectacle lens 1 was fabricated. Note that spectacle lens 1 consists only of a lens substrate; no other materials are laminated onto the lens substrate. The prescribed refractive power was set to 0.00D for S (spherical refractive power) and 0.00D for C (astigmatic refractive power). • Diameter of the lens substrate in plan view: 60.00 mm • Lens substrate type: PC (polycarbonate) • Refractive index of lens substrate: 1.589 The above information is common to all specific examples, so it will be omitted from further discussion.

[0190] In this example, the central clear area 2 was defined as a circle with a radius of 3.50 mm from the lens center, and the functional area 3 was defined as a circle with a radius of 12.50 mm from the lens center (excluding the central clear area 2). An outer clear area 4 was provided on the outer edge side of the spectacle lens 1 beyond the functional area 3. The entire area between the outer edge of the spectacle lens 1 and the functional area 3 was defined as the outer clear area 4 (the same applies to subsequent examples).

[0191] Based on that, the following configuration was adopted in this example. • Functional region 3 configuration: Convex regions 3a are discretely arranged as defocus regions. Within functional region 3, regions other than convex regions 3a are base regions 3b. • Shape of convex region 3a: Spherical • Shape of the convex region 3a in plan view: perfect circle • Refractive force of convex region 3a: 3.50D • Formation surface of convex region 3a: Surface on the object side • Arrangement of convex regions 3a in plan view: Each convex region 3a is independently and discretely arranged such that its center becomes a vertex of an equilateral triangle (the center of each convex region 3a is located at the vertices of the honeycomb structure). • Pitch between each convex region 3a (distance between the centers of the convex regions 3a): 1.50 mm • Assuming the wearer's pupil diameter is 4.00mm. • Absolute value of spherical aberration in the wearer's eye: Assumes it is zero.

[0192] <Comparative Example 1> In this example, the following changes were made from Reference Example 1. • The absolute value of the spherical aberration in the wearer's eye is assumed to be 0.80 μm.

[0193] <Example 1> In this example, the following changes were made from Comparative Example 1. • Shape of convex region 3a: Toric surface with an axial direction in the circumferential direction • Shape of the convex region 3a in plan view: Elongated shape along the circumferential direction (long axis length: 1.06 mm, short axis length: 1.00 mm) • Average refractive power of convex region 3a: 3.50D • Astigmatism caused by the convex region 3a: -0.40D with the axial direction (minimum refractive force) as the circumferential direction.

[0194] <Result> Although it will overlap with what was stated as knowledge leading up to the present invention, it will be described below.

[0195] As shown in Figure 2B, which corresponds to Comparative Example 1, the contrast ratio is lower due to spherical aberration in the eye compared to Figure 2A, which corresponds to Reference Example 1 (when spherical aberration in the eye is zero).

[0196] On the other hand, as shown in Figure 2C, which corresponds to Example 1, the contrast ratio can be maintained at a level comparable to that of Figure 2A thanks to the second refractive region, which acts as a buffer. In other words, as shown in the right-hand figure of Figure 3B, the reduction in the contrast ratio can be suppressed by canceling out local astigmatism in some parts of the eye's distribution. [Explanation of Symbols]

[0197] 1. Eyeglass lenses 2. Clear area on the central side 3. Functional Domain 3a. Non-converging regions (convex regions) on the retina 3b. Base area 4. Outer clear area P... Wavefront map of the eye C1... (Clear pupil circle used to define the boundary between the functional area and the central clear area) C2... (Clear pupil circle used to define the boundary between the functional area and the outer clear area)

Claims

1. A base region that directs a light beam entering from the object-side surface, exits from the eye-side surface, enters the wearer's pupil, and focuses onto the retina, A retinal non-focusing region is created where the light beam incident from the object side is emitted from the eyeball side, while the light beam incident within the wearer's pupil is not focused onto the retina. It has a functional area that has, At least a portion of the aforementioned non-focusing region on the retina is a buffer region capable of canceling out localized negative astigmatism caused by spherical aberration of the eye at a portion of the distribution of said astigmatism. The surface shape of the buffer region is a toric surface with an axial direction in the circumferential direction, and in a plan view, it is elongated along the circumferential direction, in the eyeglass lens.

2. In the planar view of the functional region, any non-converging region on the retina within a band-shaped region consisting of a collection of circles with a diameter of 4 mm, the center of which passes through a predetermined range of at least one diameter extending from the center of the lens, is the buffer region. The spectacle lens according to claim 1, wherein at least three buffer regions are dispersed within any circle with a diameter of 4 mm within the aforementioned band-shaped region.

3. The spectacle lens according to claim 2, wherein the dispersion of the buffer regions is such that the first interval, which is the length of the line segment connecting the centers of two buffer regions, and the second interval, which is the distance between the center of another buffer region that is closest to the line segment and whose center lies on the normal to the line segment and the line segment, are both less than 2 mm.

4. The spectacle lens according to claim 1, wherein the absolute value of the astigmatism in the buffer region is 0.25 to 0.50 D.

5. The spectacle lens according to claim 1, wherein the non-converging region on the retina has a shape that protrudes from the base region.

6. The spectacle lens according to claim 5, wherein the projection distance of the non-focusing region on the retina from the base region is greater than 1.00 μm.

7. The aforementioned non-converging region on the retina includes at least non-converging regions A1 and B1. At least the non-converging region B1 on the retina is a buffer region, In a planar view, the non-converging region A1 on the retina near the center of the lens has a longer shape in the circumferential direction compared to the non-converging region B1 on the retina farther from the center of the lens, as described in claim 1.

8. The spectacle lens according to claim 1, wherein, among the non-focusing regions on the retina on each circumference, there exist two straight lines having a relationship in which the absolute value of astigmatism in the non-focusing region on the retina that lies on a straight line passing through the center of the lens is large, and the absolute value of astigmatism in the non-focusing region on the retina that lies on a straight line perpendicular to said straight line and passing through the center of the lens is small.

9. The spectacle lens according to claim 8, wherein a mark is provided on the spectacle lens that presents information that the value of astigmatism differs depending on the circumferential position in each of the aforementioned buffer regions.

10. The aforementioned spectacle lens comprises a lens substrate and a laminated film provided so as to cover the lens substrate. The aforementioned lens substrate is The base region is formed by a first refractive region of the substrate, The substrate second refractive region which forms the basis of the non-converging region on the retina, It has, The spectacle lens according to claim 1, wherein the surface shape of the second refractive region of the base material that forms the buffer region is a toric surface having an axial direction in the circumferential direction and is elongated in the circumferential direction when viewed from above.

11. In a plan view of the lens substrate, the surface shape of the second refractive region of the substrate within a band-shaped region consisting of a collection of circles with a diameter of 4 mm, the center of which passes through a predetermined range of at least one diameter extending from the center of the lens, is a toric surface having an axial direction in the circumferential direction, and in a plan view, it has an elongated shape along the circumferential direction. The spectacle lens according to claim 10, wherein at least three substrate second refractive regions are dispersed within any circle with a diameter of 4 mm within the band-shaped region.

12. The spectacle lens according to claim 11, wherein the dispersion of the second refractive region is such that the third interval, which is the length of the line segment connecting the centers of the second refractive regions of two substrates, and the fourth interval, which is the distance between the center of another second refractive region of a substrate that is closest to the line segment and whose center lies on the normal to the line segment and the line segment, are both less than 2 mm.

13. The second refractive region of the substrate that forms the basis of the non-converging region on the retina includes at least the second refractive regions a1 and b1 of the substrate. At least the second refractive region b1 of the substrate is the base of the buffer region, In a plan view, the second refractive region b1 of the substrate, which is further from the center of the lens, has a longer shape in the circumferential direction compared to the second refractive region a1 of the substrate, which is closer to the center of the lens, as described in claim 10.

14. The spectacle lens according to claim 10, wherein the second refractive region of the substrate has a shape that protrudes from the first refractive region of the substrate.

15. The spectacle lens according to claim 14, wherein the projection distance of the second refractive region of the substrate from the first refractive region of the substrate is greater than 1.00 μm.

16. The spectacle lens according to claim 10, wherein the thickness of at least one of the laminated films is unevenly distributed around the second refractive region of the substrate, and the astigmatism value differs depending on the circumferential position in each of the buffer regions on each circumference.

17. The spectacle lens according to claim 10, having a central clear region surrounded by the annular functional region.

18. The spectacle lens according to claim 17, wherein the center of the central clear region is located at the geometric center of the lens.

19. The spectacle lens according to claim 17, wherein the center of the central clear region is located at a position shifted toward the nose with respect to the geometric center of the lens.

20. A base region that directs a light beam entering from the object-side surface, exits from the eye-side surface, enters the wearer's pupil, and focuses onto the retina, A retinal non-focusing region is created where the light beam incident from the object side is emitted from the eyeball side, while the light beam incident within the wearer's pupil is not focused onto the retina. A method for manufacturing spectacle lenses having a functional region having, At least a portion of the aforementioned non-focusing region on the retina is a buffer region that cancels out localized negative astigmatism caused by spherical aberration of the eye at a portion of the distribution of said astigmatism. The aforementioned spectacle lens comprises at least a lens substrate, The aforementioned lens substrate is The base region is formed by a first refractive region of the substrate, The substrate second refractive region which forms the basis of the non-converging region on the retina, It has, The process involves turning the mold on a lathe so that the surface shape of the second refraction region of the base material that forms the basis of the buffer region is a toric surface having an axial direction in the circumferential direction, and in a plan view, it has an elongated shape along the circumferential direction. A molding process in which the lens substrate is formed using a mold after lathe machining, A method for manufacturing eyeglass lenses, comprising the characteristics of an eyeglass lens.

21. A method for manufacturing eyeglass lenses according to claim 20, wherein, in a plan view of the lens substrate, the surface shape of the second refractive region of the substrate within a band-shaped region consisting of a collection of circles with a diameter of 4 mm, the centers of which pass through a predetermined range of at least one diameter extending from the center of the lens, is such that each of them is a toric surface having an axial direction in the circumferential direction and, in a plan view, has an elongated shape along the circumferential direction, and the turning process is performed on the mold so that at least three second refractive regions of the substrate are dispersed within any circle of a diameter of 4 mm within the band-shaped region.

22. The method for manufacturing spectacle lenses according to claim 21, wherein the dispersion of the second refractive region is such that the third interval, which is the length of the line segment connecting the centers of the second refractive regions of two substrates, and the fourth interval, which is the distance between the center of another second refractive region of a substrate that is closest to the line segment and whose center lies on the normal to the line segment and the line segment, are both less than 2 mm.

23. The second refractive region of the substrate that forms the basis of the non-converging region on the retina includes at least the second refractive regions a1 and b1 of the substrate. At least the second refractive region b1 of the substrate is the base of the buffer region, A method for manufacturing eyeglass lenses according to claim 20 or 21, wherein when machining a mold on a lathe to form the lens substrate, the lathe machining step is performed to machine the mold on a lathe so that, in a plan view, the second refractive region b1 of the substrate, which is further from the center of the lens, is elongated in the circumferential direction compared to the second refractive region a1 of the substrate, which is closer to the center of the lens.

24. A method for manufacturing eyeglass lenses according to claim 20 or 21, wherein in the turning process, the portion of the mold corresponding to the second refractive region of the substrate is recessed compared to the portion corresponding to the first refractive region of the substrate, so that the second refractive region of the substrate has a shape that protrudes from the first refractive region of the substrate.

25. The method for manufacturing spectacle lenses according to claim 24, wherein the recess distance is greater than 1.00 μm.

26. The process further includes a lamination step in which a laminated film is formed to cover the lens substrate obtained using a mold after lathe machining, A method for manufacturing an eyeglass lens according to claim 20 or 21, wherein at least one of the laminated films is formed by a dip method, thereby causing the thickness of the film to be unevenly distributed around the second refractive region of the substrate, and causing the astigmatism value to differ depending on the circumferential position in each of the buffer regions.

27. A method for manufacturing eyeglass lenses according to claim 26, wherein, among the non-focusing regions on the retina on each circumference, there exist two straight lines having a relationship in which the absolute value of astigmatism in the non-focusing region on the retina that lies on a straight line passing through the center of the lens is large, and a straight line perpendicular to that straight line that lies on a straight line passing through the center of the lens has a relationship in which the absolute value of astigmatism in the non-focusing region on the retina that lies on a straight line passing through the center of the lens is small.

28. The method for manufacturing an eyeglass lens according to claim 27, further comprising a marking step of providing a mark on the eyeglass lens that presents information that the value of astigmatism differs depending on the circumferential position in each of the aforementioned buffer regions.

29. Eyeglasses having an eyeglass lens according to any one of claims 1 to 19 fitted into a frame.

30. A method for manufacturing eyeglasses, comprising determining the orientation of the eyeglass lens using the mark on the eyeglass lens described in claim 9 as a guide according to the magnitude of spherical aberration in the wearer's eye, and then fitting the eyeglass lens into the frame.

31. Let V be the absolute value of the difference between the astigmatism of light incident on the upper retina and the astigmatism of light incident on the lower retina when a person wearing eyeglass lenses has uncorrected vision. When the wearer is wearing eyeglass lenses, let V' be the absolute value of the difference between the astigmatism of light passing through the non-focusing region on the retina and incident on the upper retina, and the astigmatism of light incident on the lower retina. A method for designing eyeglass lenses, comprising determining the frame insertion direction of the eyeglass lens according to any one of claims 1 to 19 such that V' is larger than V.

32. A method for manufacturing eyeglasses, comprising framing the eyeglass lenses according to the orientation determined by the design method described in claim 31.

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