eyeglass lenses

Abstract

To provide a spectacle lens capable of suppressing the progression of refractive error even in peripheral vision.SOLUTION: A spectacle lens provided herein has a first region formed such that transmitted light focuses at a predetermined point in an eye, and a plurality of second regions formed such that the transmitted light focuses at a point defocused from the predetermined point. The plurality of second regions has negative spherical aberration.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a spectacle lens. [Background technology]

[0002] In recent years, the number of people suffering from myopia has been on the rise. It has been reported that when part of the light entering the eye is focused on the back of the retina, the progression of myopia is accelerated, and when it is focused on the front, the progression is suppressed. For this reason, there is a spectacle lens for suppressing the progression of refractive errors such as myopia, which has a first region formed so that transmitted light is focused at a predetermined position (for example, a position on the retina of the eyeball) and a second region formed so that transmitted light is focused at a position different from the predetermined position (for example, a position other than the retina of the eyeball).Specifically, there is a spectacle lens in which a convex surface as the first region, which is the surface on the object side, is formed with a plurality of convex regions having a curved surface different from the convex surface and protruding from the convex surface as the second region (for example, see Patent Document 1). According to the spectacle lens of such a configuration, the light rays that enter from the surface on the object side and exit from the surface on the eyeball side are in principle focused on the retina of the wearer, but the light rays that pass through the convex area are focused at a position closer to the object side than on the retina. In other words, the approach adopted is to reduce the light that forms an image behind the retina and increase the light that forms an image in front of the retina, which suppresses the progression of myopia. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] US Patent Application Publication No. 2017 / 0131567 Summary of the Invention [Problem to be solved by the invention]

[0004] Light entering the eye is perceived not only in the central visual field, which includes the fovea of ​​the retina, but also in the peripheral visual field, which is outside the central visual field. However, it is known that when perceiving light incident on the eyeball, the central visual field is highly sensitive to light and dark patterns with high spatial frequencies, while the peripheral visual field is highly sensitive to light and dark patterns with low spatial frequencies. In other words, the peripheral visual field has a lower spatial resolution than the central visual field, and light stimuli that serve as a clue to finding the focal position are perceived differently from those in the central visual field. Therefore, in peripheral vision, the light that passes through the second region is not perceived to be focused at a position closer to the object than on the retina, and as a result, the effect of suppressing the progression of myopia may not be achieved.

[0005] In this regard, it is possible to deal with this by making the lens structure different between the corresponding part of the central visual field and the corresponding part of the peripheral visual field. Specifically, it is possible to make the shape or power of the second region different between the corresponding part of the central visual field and the corresponding part of the peripheral visual field, or to give a strong curvature of field to one part. However, if the lens structure is partially different, the surface of the entire lens becomes uneven, which impairs the appearance. In addition, when the eyeball rotates, the corresponding relationship between the distribution of the lens structure and the line of sight changes, so that a sufficient effect is not necessarily obtained.

[0006] An object of the present invention is to provide a technique that enables spectacle lenses to exert an effect of suppressing the progression of refractive errors even in peripheral vision. [Means for solving the problem]

[0007] The present invention has been devised to achieve the above object. The first aspect of the present invention is A spectacle lens having a first region formed so that transmitted light is focused at a predetermined position in the eye, and a plurality of second regions formed so that the transmitted light is focused at a position defocused from the predetermined position, The second regions have negative spherical aberration. It is a spectacle lens.

[0008] A second aspect of the present invention is The second regions are configured to have the negative spherical aberration such that light perceived in peripheral vision is perceived as a false focus at a position other than the predetermined position. The spectacle lens according to the first aspect.

[0009] A third aspect of the present invention is The spherical aberrations of the second regions are given so that an evaluation value using a Gabor function for the transmitted light in the peripheral vision has a maximum value at a position other than the predetermined position. The spectacle lens according to the first or second aspect.

[0010] A fourth aspect of the present invention is The spherical aberrations of the second regions are given so that an evaluation value using a Gabor function for the transmitted light in the peripheral vision has a maximum value at a position other than the predetermined position. The spectacle lens according to any one of the first to third aspects.

[0011] A fifth aspect of the present invention is The second regions are configured to have the negative spherical aberration so that a position where a light ray passing through the outermost portion of the second region intersects with a light ray passing from the outermost portion to the inside by 10% of the radius of the second region is between the predetermined position and a position defocused from the predetermined position. The spectacle lens according to any one of the first to fourth aspects.

[0012] A sixth aspect of the present invention is a method for producing a composition comprising the steps of: The plurality of second regions are formed in an aspheric shape such that the curvature decreases with increasing distance from the center of the second region. The spectacle lens according to any one of the first to fifth aspects.

[0013] A seventh aspect of the present invention is At least three of the plurality of second regions are disposed within a range of a pupil diameter through which the transmitted light passes, and the sizes and intervals of the plurality of second regions are formed so that a figure connecting the reference points of the three second regions forms an acute triangle. The spectacle lens according to any one of the first to sixth aspects.

[0014] An eighth aspect of the present invention is a method for producing a composition comprising the steps of: The plurality of second regions are arranged in a hexagonal manner. The spectacle lens according to any one of the first to seventh aspects.

[0015] A ninth aspect of the present invention is a method for producing a composition comprising the steps of: The plurality of second regions are configured by a multi-layer structure, the innermost layer in the multilayer structure is a layer having a function of imparting a defocus power, The outer layers have the effect of imparting negative spherical aberration. The spectacle lens according to any one of the first to eighth aspects. Effect of the Invention

[0016] According to the present invention, it is possible for the spectacle lenses to exhibit the effect of suppressing the progression of refractive error even in peripheral vision. [Brief description of the drawings]

[0017] [Figure 1] FIG. 1 is a front view showing an example of a spectacle lens in an embodiment of the present invention. [Diagram 2] 2 is a schematic cross-sectional view (part 1) showing the path of light passing through the eyeglass lens shown in FIG. [Diagram 3] 2 is a schematic cross-sectional view (part 2) showing the path of light passing through the eyeglass lens shown in FIG. [Figure 4] 1 is a schematic cross-sectional view showing the paths of the chief rays of light incident on each segment for central and peripheral vision. [Diagram 5] 2 is an enlarged view showing the shape and curvature of a convex region in the eyeglass lens shown in FIG. 1. [Figure 6] 6 is an explanatory diagram showing a simulation image in which light passing through the convex region shown in FIG. 5 is perceived by the central visual field of the eyeball. FIG. [Figure 7] 6 is an explanatory diagram showing a simulation image in which light passing through the convex region shown in FIG. 5 is perceived by the peripheral visual field of the eyeball. FIG. [Figure 8] 2A to 2C are explanatory diagrams showing the shapes of segments of each eyeglass lens according to an embodiment of the present invention and a comparative example. [Figure 9] FIG. 2 is an explanatory diagram showing the curvature distribution of segments of each eyeglass lens according to an embodiment of the present invention and a comparative example. [Figure 10] FIG. 2 is an explanatory diagram showing an example of a graph of Gabor coefficients (evaluation values) for a spectacle lens according to an embodiment of the present invention. [Figure 11] FIG. 11 is an explanatory diagram showing an example of a graph of Gabor coefficients (evaluation values) for a spectacle lens according to a comparative example. [Figure 12] FIG. 11 is a side cross-sectional view showing an example of the configuration of a main part of a spectacle lens according to another embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Note that the following description is merely an example, and the present invention is not limited to the illustrated embodiment.

[0019] (1) Composition of eyeglass lenses First, the configuration of the eyeglass lens exemplified in this embodiment will be described.

[0020] The spectacle lens exemplified in this embodiment is a refractive error progression inhibiting lens that inhibits the progression of refractive error in the eye of the spectacle wearer. The refractive error progression inhibiting lens is configured to have a first region having a first refractive power based on a prescription for correcting the refractive error of the eye, and a second region having a refractive power different from the first refractive power and having a function of focusing on a position other than the retina of the eye so as to inhibit the progression of the refractive error of the eye.

[0021] The refractive error progression inhibiting lenses include myopia progression inhibiting lenses that inhibit the progression of myopia, and hyperopia progression inhibiting lenses that inhibit the progression of hyperopia. In the following description, myopia progression inhibiting lenses will be taken as an example.

[0022] Fig. 1 is a front view showing an example of a spectacle lens in the present embodiment, Fig. 2 and Fig. 3 are schematic cross-sectional views showing the path of light passing through the spectacle lens shown in Fig. 1.

[0023] (Overall composition) The eyeglass lens 1 according to this embodiment has an object-side surface and an eyeball-side surface. The "object-side surface" is the surface that is located on the object side when eyeglasses including the eyeglass lens 1 are worn by a wearer. The "eyeball-side surface" is the opposite, that is, the surface that is located on the eyeball side when eyeglasses including the eyeglass lens 1 are worn by a wearer. In this embodiment, the object-side surface is a convex surface, and the eyeball-side surface is a concave surface. In other words, the eyeglass lens 1 is a meniscus lens.

[0024] The eyeglass lens 1 is also configured with a lens substrate. The lens substrate is formed of a thermosetting resin material, such as thiourethane, allyl, acrylic, or epithio. As the resin material constituting the lens substrate, other resin materials that can obtain a desired refractive index may be selected. Also, instead of a resin material, the lens substrate may be made of inorganic glass.

[0025] At least one of the object side surface and the eyeball side surface of the lens substrate is coated with a coating. Examples of the coating include a hard coat film and an anti-reflection film (AR film), and other films may be formed in addition to these. 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 liquid, spin coating, or the like. By covering the spectacle lens 1 with such a hard coat film, the durability of the spectacle lens 1 can be improved. The anti-reflection film is formed by vacuum deposition of an anti-reflection agent such as ZrO2, MgF2, Al2O3, etc. By coating with such an anti-reflection film, the visibility of an image passing through the eyeglass lens 1 can be improved.

[0026] (convex area) In the spectacle lens 1 according to the present embodiment, for example, a plurality of convex regions are formed on the object side surface (convex surface) of the lens substrate so as to protrude from the surface toward the object side. Each convex region is formed by a curved surface having a different curvature from the object side surface of the lens substrate. When a lens substrate having such a convex region is covered with a coating such as a hard coat film or an anti-reflection film, a plurality of convex regions are formed on the surface of the coating in imitation of the convex regions of the lens substrate. That is, a plurality of convex regions 6 formed to protrude from the object side surface (convex surface) of the spectacle lens 1 are arranged on the object side surface (convex surface) depending on the thickness of the convex regions of the lens substrate and the coating covering the convex regions. Here, a case where a plurality of convex regions 6 are arranged on the object side surface is illustrated, but this is not necessarily limited thereto, and it is sufficient that the convex regions 6 are arranged on at least one of the object side surface and the eyeball side surface.

[0027] As shown in Fig. 1, the multiple convex regions 6 are regularly arranged on the surface of the eyeglass lens 1. In the illustrated example, the multiple convex regions 6 are partially arranged near the center of the lens, but this is not limited to this, and as long as the respective convex regions 6 are regularly arranged, they may be arranged over the entire surface of the lens, or may be arranged circumferentially so as to surround the center of the lens.

[0028] Moreover, the multiple convex regions 6 are arranged in the form of independent islands (i.e., spaced apart and not adjacent to each other). That is, in this embodiment, the convex regions 6 are arranged discretely (i.e., not continuous with each other and scattered apart). However, although an example is given here in which all the convex regions 6 are independent islands, this is not necessarily limited thereto, and the convex regions 6 may be arranged such that the outer edges of adjacent regions are connected or in contact with each other.

[0029] (Optical properties) In the eyeglass lens 1 configured as described above, by having a convex area 6 on the object-side surface 3, the following optical characteristics are realized, and as a result, the progression of refractive errors such as myopia in the eyeglass wearer can be suppressed.

[0030] As shown in FIG. 2, in the eyeglass lens 1, light incident on the object side surface 3 of the region where the convex region 6 is not formed (hereinafter referred to as the "base region") is focused on the retina 20A of the eyeball 20 after exiting from the eyeball side surface 4. That is, the light beam passing through the eyeglass lens 1 is, in principle, focused on the retina 20A of the eyeglass wearer. In other words, the curvature of the base region of the eyeglass lens 1 is set according to the eyeglass wearer's prescription so as to focus on the retina 20A, which is the predetermined position A. Therefore, the base region of the eyeglass lens 1 has a first refractive power based on a prescription for correcting the refractive error of the eyeglass wearer's eye, and functions as a "first region" formed so that the light passing through the lens is focused on the retina 20A, which is the predetermined position A. Note that "focusing" in this specification means that light is concentrated to form an image, but it does not necessarily have to be an image without aberration, and may have spherical aberration or astigmatism. In this specification, the term "focus" refers to a point that is recognized as a point of maximum value for the visual sense.

[0031] 3, in the eyeglass lens 1, light incident on the convex region 6 is focused at a position (defocus position) closer to the object side than the retina 20A of the eyeball 20 after being emitted from the eyeball-side surface 4. In other words, the convex region 6 converges the light emitted from the eyeball-side surface 4 to a position B closer to the object side than a predetermined position A. This convergence position B is located at positions B1, B2, B3, ... B according to each of the multiple convex regions 6. N Therefore, each of the multiple convex regions 6 functions as a "second region" formed so that the light transmitted through the lens is focused at a defocused position B from a predetermined position A. Hereinafter, the convex regions 6 functioning as second regions are also referred to as "segments."

[0032] In this way, in principle, the spectacle lens 1 causes light rays incident on the object-side surface 3 to exit from the eyeball-side surface 4 and converge at a predetermined position A, while in the portion where the segments 6 are arranged, the light rays are converged at a position B (B1, B2, B3, ... B) closer to the object side than the predetermined position A. N ) in the direction B. In other words, the eyeglass lens 1 has a function of converging light rays to position B closer to the object side, separate from the function of converging light rays to achieve the eyeglass wearer's prescription. By having such optical properties, the eyeglass lens 1 can exert an effect of suppressing the progression of refractive errors such as myopia in the eyeglass wearer (hereinafter referred to as the "myopicia suppression effect").

[0033] (2) Overview of peripheral vision The optical characteristics of the spectacle lens 1 described above are mainly for the case where the incident light reaches the central visual field including the fovea of ​​the retina after passing through the lens and is perceived in the central visual field. However, the retina of the eye is also adapted to peripheral vision. In this case, "peripheral vision" refers to the perception of light in the peripheral visual field outside the central visual field.

[0034] FIG. 4 is a schematic cross-sectional view showing the paths of the chief rays of light incident on each segment in the case of central vision and peripheral vision.

[0035] In many cases, including the example of FIG. 4, light reaching the peripheral visual field 20B enters the spectacle lens 1 at an angle relative to light reaching the central visual field 20C.

[0036] Light at an angle to the light reaching the central visual field 20C passes through the spectacle lens 1 and further passes through the pupil 20D of the eyeball 20, reaches the peripheral visual field 20B of the retina 20A, and is perceived in the peripheral visual field 20B. The peripheral visual field 20B has a lower spatial resolution than the central visual field 20C. Specifically, the photoreceptor cells in the peripheral visual field 20B have only about 10 to 20% of the resolution of the central visual field 20C. Therefore, in the peripheral visual field 20B, a light stimulus serving as a clue to find the focal position may be perceived differently from that in the central visual field 20C.

[0037] Therefore, in peripheral vision, even if light converges at position B as described above, the peripheral visual field 20B may not detect it. In other words, since the optical stimulus used as a clue to find the focal position in the peripheral visual field 20B is different from that in the central visual field 20C, it is not perceived that the light transmitted through the segment 6 of the spectacle lens 1 is focused at position B, which is closer to the object side than on the retina 20A, and as a result, the effect of suppressing the progression of myopia may not be achieved.

[0038] Here, the difference between an image perceived in the central visual field 20C and an image perceived in the peripheral visual field 20B will be specifically described. FIG. 5 is an enlarged view showing the shape and curvature of a segment 6 in the eyeglass lens 1. As shown in FIG. Here, attention is focused on an area C in which segments are arranged in a hexagonal pattern as shown in FIG. 5, and a description is given of how light passing through each segment 6 in that area C is perceived.

[0039] FIG. 6 is an explanatory diagram showing a simulation image in which light passing through a segment 6 of the spectacle lens 1 is perceived by the central visual field 20C of the eyeball 20. As shown in FIG. The example in the figure shows the results of a simulation of how light passing through segment 6 is perceived in the central visual field 20C at multiple locations between 3.4D and 0D for a spectacle lens 1 in which segment 6 is formed so as to focus at position B, which is 3.4D closer to the object than the specified position A, when the specified position A on the retina 20A is set to "0D (diopters)." As shown in Figure 6, a simulation taking into account the resolution of the central visual field 20C shows that the light transmitted through each segment 6 is perceived as being most concentrated at position B (i.e., position +3.4D), where the diameter of the white circle indicating the perception state of light is smallest (see arrow D in Figure 6).

[0040] FIG. 7 is an explanatory diagram showing a simulation image in which light passing through a segment 6 of the spectacle lens 1 is perceived by the peripheral visual field 20B of the eyeball 20. As shown in FIG. In the illustrated example, similarly to the case of the central visual field 20C described above, the simulation results at a plurality of points between a predetermined position A (0D) and a position B (+3.4D) closer to the object side than the predetermined position A are shown. As shown in Fig. 7, according to a simulation that takes into account the resolution of the peripheral visual field 20B, unlike the central visual field 20C described above, the light is not perceived as being most concentrated at position B (i.e., at +3.4D). In other words, it can be seen that the light passing through each segment 6 is not perceived individually, but is perceived as a single light that combines with the other light, and is perceived as being blurred overall.

[0041] As described above, the central visual field 20C and the peripheral visual field 20B have different light perception modes due to the difference in resolution. Therefore, even if the segment 6 is formed to exert a myopia suppression effect on the central visual field 20C, it does not necessarily exert a myopia suppression effect on the peripheral vision by itself.

[0042] In order to achieve the myopia suppression effect even in peripheral vision, it is possible to make the lens structure of the eyeglass lens 1 different between the corresponding part of the central vision 20C and the corresponding part of the peripheral vision 20B. Specifically, it is possible to make the shape and power of the segment 6 different between the corresponding part of the central vision 20C and the corresponding part of the peripheral vision 20B, or to give a strong curvature of field to one part. However, if the lens structure is partially different, the surface of the entire lens becomes uneven, and the appearance is impaired. In addition, when the eyeball rotates, the correspondence relationship between the distribution of the lens structure and the line of sight changes, so that a sufficient effect is not necessarily obtained. In other words, it is not preferable to make the lens structure different between the corresponding part of the central vision 20C and the corresponding part of the peripheral vision 20B. In addition, it is not preferable that the myopia suppression effect for the central vision 20C is impaired by considering the peripheral vision.

[0043] The present inventors have conducted extensive research into this issue and have come up with the following lens structure that can provide at least some myopia suppression effect in peripheral vision without compromising the myopia suppression effect in the central visual field 20C.

[0044] For example, in peripheral vision, light is perceived to be blurred overall due to the difference in resolution from the central visual field 20C. That is, unlike the central visual field 20C, light is not perceived to be most concentrated at position B (i.e., at +3.4D). However, even if light is not perceived to be most concentrated at position B, if light is perceived to be most concentrated at a position closer to the object side than position A (i.e., at 0D) (for example, see arrow E shown in FIG. 7) (i.e., if the diameter of the white circle in the figure showing the light perception state is smallest), it is considered that a myopia suppression effect can be exerted to some extent. In order to make light perceived to be concentrated at least at a position closer to the object side than position A in peripheral vision, it is sufficient to utilize the overlap of blurred images due to the low spatial resolution in the peripheral visual field 20B. That is, in peripheral vision, light transmitted through each segment 6 is perceived as a blurred image due to low resolution, but if the light energy is increased by the overlapping part of the blurred images, it is possible to make it possible to perceive as if a convergence point exists at the position of the overlapping part. Hereinafter, the use of overlapping blurred images to cause the perception of a pseudo-focus point at a position other than the optical focal position will be referred to simply as "false focus."

[0045] To generate such false focusing more effectively, each segment may have negative spherical aberration characteristics so that the optical energy at the edge of the blurred image of each segment is higher than that at the center of the blurred image.

[0046] In other words, in order to enable the suppression of the progression of refractive error even in peripheral vision, which has a low spatial resolution, the inventors have come up with a lens structure that imparts negative spherical aberration to each of the multiple segments 6 so that the light perceived in peripheral vision is recognized as a false focus at a desired position (i.e., a position other than focal position A on the retina 20A).

[0047] (3) Spherical aberration of the segments The spherical aberration of the multiple segments 6 in the spectacle lens 1 according to this embodiment will be described below.

[0048] Spherical aberration refers to a phenomenon in which the focusing position differs in the optical axis direction depending on the distance from the center of each segment 6. In particular, when the focusing position in the eye of light rays that pass through a more peripheral portion of a segment 6 is located farther away from the spectacle lens 1 than the focusing position in the eye of light rays that pass through the center of the segment 6, it is said to have "negative spherical aberration."

[0049] When spherical aberration is present, the density of the light rays emitted from the segment 6 becomes non-uniform. In particular, on the side farther from the spectacle lens 1 than the paraxial focusing position, the light rays become dense at the edge of the light beam, and a ring-shaped region with high light energy appears (see, for example, FIGS. 6(d) and (e)).

[0050] When such spherical aberration is present, light rays at different distances from the center of segment 6 may intersect at a point away from the optical axis or the principal ray of segment 6. In other words, ring-shaped regions may overlap. When this happens, a region with particularly high light energy appears in the light beam. If the light energy is increased by the overlapping portion of ring-shaped regions in this way, it is possible to perceive a light focusing point as if it exists at the position of the overlap, that is, to generate false focusing.

[0051] As described above, if each segment 6 has negative spherical aberration, light perceived in peripheral vision can be recognized as a false focus at a position other than the focal position A on the retina 20A.

[0052] One method for imparting negative spherical aberration to each segment 6 is to make the convex shape of the segment 6 aspheric. Specifically, by setting the aspheric shape such that the curvature of the convex surface decreases with increasing distance from the center of the segment 6, negative spherical aberration can be imparted.

[0053] (4) Segment placement As described above, false focusing occurs when the light beams of the multiple segments 6 overlap. Therefore, it is preferable that the eyeglass lens 1 includes multiple segments 6 in the pupil. Specifically, it is preferable that at least three of the multiple segments 6 are arranged within the range of the pupil diameter through which the transmitted light passes, and that the size and arrangement interval of each segment 6 are formed so that a figure connecting the reference points of the three segments 6 forms an acute triangle. Here, the reference point of the segment 6 refers to a point that serves as a reference for identifying the position where the segment 6 is arranged. For example, if the segment 6 is circular in plan view, the center point of the segment 6 can be the reference point.

[0054] To achieve such an arrangement, it is most preferable that the multiple segments 6 are arranged in a hexagonal arrangement (particularly, in a hexagonal close-packed arrangement).

[0055] In such a spectacle lens 1, whether or not each segment 6 causes false focusing can be verified (evaluated) by, for example, the method described below.

[0056] The human visual field perceives images through a process similar to the Gabor transform (reference: J. Daugman, "Entropy reduction and decorrelation in visual coding by oriented neural receptive fields", Trans. on Biomedical Engineering, Vol. 36, No. 1, pp. 107-114 (1989)). Following this example, it is believed that it is possible to verify (evaluate) to some extent how light is perceived in the human visual field by an evaluation value using the Gabor function shown in the following formula (1). In formula (1), x is the horizontal coordinate on the retina, and y is the vertical coordinate on the retina, both in mm units. In this example, the Gabor function in the x direction is exemplified, but a Gabor function in the y direction or an intermediate direction may also be used.

[0057]

number

[0058] In the evaluation using the Gabor function, for example, the Gabor function shown in the above formula (1) is convolved with a geometrical optical spot (not a spot considering the spatial resolution of the human visual field), the maximum value of the convolution result is set as the Gabor coefficient (i.e., the evaluation value using the Gabor function), and the evaluation value is used to evaluate whether false focusing occurs. The Gabor coefficient used for evaluation corresponds to the evaluation value of contrast visually recognized by humans. Specifically, in the above formula (1), calculation is performed with a=0.015 in the central visual field and a=0.105 in the peripheral visual field, and the Gabor coefficient (evaluation value) is displayed on a graph by normalizing to a value of 1 at the best focus position. As will be described in detail later, the graph can be created by taking the distance (defocus amount, unit: diopter) between a predetermined position A on the retina and the position B where each segment 6 is focused on on the horizontal axis and the Gabor coefficient (evaluation value using the Gabor function, unit: dimensionless quantity) on the vertical axis.

[0059] When such a graph is created, if false focusing occurs between the segments 6 in peripheral vision, the evaluation value using the Gabor function for the light passing through the segment 6 will have a maximum value at a position other than the predetermined position A (0D). Therefore, if the evaluation value using the Gabor function for the light passing through each segment 6 in peripheral vision has a maximum value at a position other than the predetermined position A (0D) on the graph that is the evaluation result using the Gabor function, it can be said that the spectacle lens 1 in which the segment 6 is arranged has spherical aberration given to each segment 6 and each segment 6 is arranged so as to cause false focusing at a position other than the predetermined position A.

[0060] It is more preferable that the local maximum value is the maximum value. However, the local maximum value does not necessarily have to be the maximum value, and as long as the local maximum value is large enough, it will be recognized as false light collection even if it is not the maximum value. For example, the local maximum value may be larger than the intermediate value between the maximum value and the minimum value. EXAMPLES

[0061] The present invention will be described in more detail below with reference to examples. Here, the examples will be described, and comparative examples will also be briefly described. In addition, evaluation results using Gabor functions will be described in the examples and comparative examples. It goes without saying that the present invention is not limited to the examples described below.

[0062] (Example) As an example, a spectacle lens 1 was formed in which multiple segments 6 were arranged so that the diameter D of each segment 6 was 0.8 mm, the distance L between adjacent segments 6 was 1.05 mm, the area ratio K of the segments 6 was 0.5, and the power P given to each segment 6 was 3.4D.

[0063] Segment 6 has a radius of curvature r = 177 mm, a conic coefficient k = 0, and a fourth-order aspheric coefficient A = -8.17 × 10 -4 The shape is obtained by adding to the base shape the amount of sag Z according to the following equation (2) relative to the distance h from the center of the segment, and a constant term to make the boundary between the segment and the base shape continuous.

[0064]

number

[0065] FIG. 8 is an explanatory diagram showing the shape of a segment of a spectacle lens according to an embodiment. In the drawing, the cross-sectional shape of the segment 6 in the eyeglass lens 1 according to the embodiment (that is, the shape obtained by adding the sag amount Z according to the above formula (2) to the base shape) is shown by a solid line.

[0066] In manufacturing the eyeglass lens 1 having such a configuration, first, the lens substrate is molded by a known molding method such as cast polymerization. For example, a mold having a molding surface with multiple recesses is used to perform molding by cast polymerization, thereby obtaining a lens substrate having a convex region on at least one surface. In this case, a mold having multiple recesses formed thereon may be used so as to meet the above-mentioned use. After the lens substrate is obtained, a coating such as a hard coat film or an anti-reflection film is formed on the surface of the lens substrate as necessary. The coating can be formed by using the known film forming methods described above. By using the manufacturing method with the above procedure, the eyeglass lens 1 according to the embodiment is obtained.

[0067] FIG. 9 is an explanatory diagram showing the curvature distribution of segments of a spectacle lens according to an embodiment. In the figure, the curvature distribution of the segment 6 in the spectacle lens 1 according to the embodiment (that is, the curvature distribution of the aspheric shape) is shown by a solid line.

[0068] As shown in FIG. 9, for the eyeglass lens 1 of the embodiment, the curvature near the center of the segment 6 is 5.6[1 / M], while the curvature near the outermost portion of the segment 6 is smaller at 4.1[1 / M].

[0069] With segment 6 as described above, negative spherical aberration occurs, and the point at which a ray passing through the outermost part of segment 6 intersects with a ray passing 10% of the radius of segment 6 inward from the outermost part is located 1.7D in front of retina 20A, which is the specified position A, that is, at the midpoint between retina 20A and focal position B of segment 6 defocused from retina 20A.

[0070] 10 is an explanatory diagram showing an example of a graph of Gabor coefficients (evaluation values) for a spectacle lens 1 according to an embodiment. The graph in the example shows the distance (defocus amount) between a predetermined position A (0D) on the retina and a position B (3.5D) where each segment 6 is focused on the horizontal axis, and the Gabor coefficient (evaluation value using a Gabor function) on the vertical axis, and shows the Gabor coefficient (evaluation value) normalized to a value of 1 at the best focus position. In the graph, the Gabor coefficient calculated taking into account the resolution of the central visual field 20C is shown by a solid line, and the Gabor coefficient calculated taking into account the resolution of the peripheral visual field 20B (i.e., the Gabor coefficient in the case of peripheral vision) is shown by a dashed line.

[0071] 10, it can be seen that in the case of peripheral vision, indicated by the dashed line, the Gabor coefficient has a maximum value at the point of 1.7 D. In other words, it was confirmed that in such spectacle lens 1, each segment 6 generates false light focusing at a position other than the predetermined position A on the retina, and as a result, it is possible to exert a myopia suppression effect even in the case of peripheral vision without impairing the myopia suppression effect on the central visual field 20C.

[0072] (Comparative Example) Here, a brief description will be given of the comparative spectacle lens. The comparative spectacle lens has a shape described in the above embodiment, but the term of the fourth-order aspheric coefficient A in formula (2) is changed to A=0. That is, the segments in the comparative spectacle lens have a spherical shape (see the dashed lines in Figs. 8 and 9).

[0073] 11 is an explanatory diagram showing an example of a graph of Gabor coefficients (evaluation values) for a spectacle lens according to a comparative example. In the graph of the example, the horizontal axis, vertical axis, solid lines, dashed lines, etc. are the same as those in the graph shown in FIG.

[0074] According to the graph shown in Fig. 11, in the case of peripheral vision shown by the dashed line, the Gabor coefficient has a maximum value at the predetermined position A (0D). In other words, the spectacle lens according to the comparative example does not cause false focusing at positions other than the predetermined position A (0D) because the segments do not have spherical aberration. Therefore, the spectacle lens according to the comparative example 1 cannot exert a myopia suppression effect in the case of peripheral vision.

[0075] (Variations, etc.) Although the embodiments and examples of the present invention have been described above, the technical scope of the present invention is not limited to the above-mentioned exemplary disclosure contents, and various modifications are possible without departing from the gist of the present invention.

[0076] FIG. 12 is a side cross-sectional view showing an example of the configuration of a main part of a spectacle lens according to another embodiment. The spectacle lens in the figure is configured by providing an aspherical layer 12 on a substrate 11 having a defocus power in order to make the segments aspherical. For example, the substrate 11 may be a resin lens substrate formed by injection molding, and the aspherical layer 12 may be a hard coat film. By using such a configuration, it becomes easy to adjust the myopia suppression effect to suit each individual. That is, the segment having negative spherical aberration may be formed of a multi-layer structure, in which the innermost layer (specifically, the layer formed of the base material 11) in the multi-layer structure is a layer that has the effect of imparting defocus power, and the layer outside of that (specifically, the layer formed of the aspheric layer 12) is a layer that has the effect of imparting negative spherical aberration.

[0077] Also, for example, in the above disclosure, the spectacle lens 1 having the convex region 6 on the object-side surface 3 is given as an example, but the present invention can be applied to spectacle lenses having other configurations. That is, the present invention can be applied not only to a lens structure having the convex region 6 on the lens surface, but also to a lens structure having a smooth lens surface, so long as the spectacle lens has a first region formed so that transmitted light is focused at a predetermined position and a plurality of second regions formed so that transmitted light is focused at a defocus position different from that of the first region.

[0078] Furthermore, for example, in the above disclosure, the case where the spectacle lenses are myopia progression inhibiting lenses has been mainly taken as an example, but the present invention can also be applied to hyperopia progression inhibiting lenses.

[0079] In addition, for example, in the above disclosure, the convex regions (segments) 6 are mainly arranged in a hexagonal pattern, but the present invention is not limited to this. That is, the present invention may be applied to an arrangement other than a hexagonal pattern, as long as each convex region (segment) is arranged to generate false light focusing in peripheral vision. [Explanation of symbols]

[0080] 1... eyeglass lens, 3... object side surface, 4... eyeball side surface, 6... convex region (segment), 11... substrate, 12... aspheric layer, 20... eyeball, 20A... retina, 20B... peripheral visual field, 20C... central visual field

Claims

1. A spectacle lens having a first region formed so that transmitted light is focused on a retina, which is a predetermined position in an eye, and a plurality of second regions formed so that the transmitted light is focused at a position defocused from the predetermined position, The plurality of second regions are regularly arranged on the lens surface, each of which has a negative spherical aberration; The size and arrangement interval of the plurality of second regions are formed so that, when a light beam having a size of a pupil diameter at the lens surface among the transmitted light beams is assumed, the light beam includes the second region and passes through the lens surface, at least three of the plurality of second regions are arranged within a range of a pupil diameter through which the light beam passes. Glasses lenses.

2. The second regions are configured to have the negative spherical aberration such that light perceived in peripheral vision is perceived as a false focus at a position other than the predetermined position. The eyeglass lens of claim 1 .

3. The spherical aberrations of the second regions are given so that an evaluation value using a Gabor function for the transmitted light in the peripheral vision has a maximum value at a position other than the predetermined position. The eyeglass lens according to claim 2.

4. The spherical aberrations of the second regions are given so that an evaluation value using a Gabor function for the transmitted light in the peripheral vision has a maximum value at a position other than the predetermined position. The spectacle lens according to claim 2 or 3.

5. The second regions are configured to have the negative spherical aberration so that a position where a light ray passing through the outermost portion of the second region intersects with a light ray passing from the outermost portion to the inside by 10% of the radius of the second region is between the predetermined position and a position defocused from the predetermined position. The eyeglass lens according to claim 1 .

6. The plurality of second regions are formed in an aspheric shape such that the curvature decreases with increasing distance from the center of the second region. The spectacle lens according to any one of claims 1 to 5.

7. The sizes and arrangement intervals of the plurality of second regions are formed so that a figure connecting the reference points of the three second regions forms an acute triangle. The spectacle lens according to any one of claims 1 to 6.

8. The plurality of second regions are arranged in a hexagonal manner. The spectacle lens according to any one of claims 1 to 7.

9. The plurality of second regions are configured by a multi-layer structure overlapping in the optical axis direction, the layer closest to the eyeball in the multilayer structure is a layer having a function of imparting defocus power; The layer closer to the object side has the effect of imparting negative spherical aberration.

9. The spectacle lens according to claim 1.

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