1. An eyeglass lens, comprising:

a 1 st region formed to focus the transmitted light at a predetermined position in the eye, an

A plurality of 2 nd regions formed to focus the transmitted light at a position defocused from the predetermined position,

wherein the plurality of No. 2 regions have negative spherical aberration.

2. The spectacle lens according to claim 1,

the plurality of 2 nd regions are configured to have the negative spherical aberration so that light perceived in peripheral vision is recognized as a pseudo spotlight at a position other than the predetermined position.

3. The spectacle lens according to claim 1 or 2,

an estimated value obtained using a gabor function for the transmitted light in the peripheral vision is given to the spherical aberration of the plurality of 2 nd regions so that the estimated value has a maximum value at a position other than the predetermined position.

4. The spectacle lens according to any one of claims 1 to 3,

an estimated value obtained using a gabor function for the transmitted light in the peripheral vision is given to spherical aberrations of the plurality of 2 nd regions such that the estimated value has a maximum value at a position other than the predetermined position.

5. The spectacle lens according to any one of claims 1 to 4,

the plurality of 2 nd regions are configured to have the negative spherical aberration such that a position where a ray passing through an outermost portion of the 2 nd region intersects a ray passing through 10% of a radius of the 2 nd region from the outermost portion to an inner side is between the predetermined position and a position defocused from the predetermined position.

6. The spectacle lens according to any one of claims 1 to 5,

the plurality of 2 nd regions are formed in an aspherical shape having a curvature that is smaller as being farther from the center of the 2 nd region.

7. The spectacle lens according to any one of claims 1 to 6,

the size and arrangement interval of the plurality of 2 nd regions are formed as follows: at least 3 of the 2 nd regions are arranged within a range of a pupil diameter through which the transmitted light passes, and a figure connecting respective reference points of the 3 2 nd regions is an acute triangle.

8. The spectacle lens according to any one of claims 1 to 7,

the plurality of 2 nd regions are configured in a hexagonal shape.

9. The spectacle lens according to any one of claims 1 to 8,

the plurality of 2 nd regions are formed of a multi-layered structure,

the innermost layer in the multilayer structure is a layer having the effect of imparting a defocus degree,

the layer located on the outer side of the layer is a layer having an effect of imparting negative spherical aberration.

Background

In recent years, the near vision population is on an increasing trend. Regarding myopia, it has been reported that when a part of light incident on an eyeball is imaged deep in the retina, forward movement of light is promoted, and when imaging is performed in front of the eye, forward movement of light is suppressed.

Therefore, as a spectacle lens for suppressing progression of ametropia such as myopia, there are the following spectacle lenses: having a 1 st region formed so that transmitted light is focused at a predetermined position (e.g., a position on the retina of the eyeball) and a 2 nd region formed so that transmitted light is focused at a position different from the predetermined position (e.g., a position other than on the retina of the eyeball). Specifically, a plurality of convex regions having a curved surface different from that of a convex surface and protruding from the convex surface are formed as a 2 nd region on the surface on the object side (i.e., the convex surface as a 1 st region) (see, for example, patent document 1).

According to the eyeglass lens having this configuration, the light beam entering from the object-side surface and exiting from the eyeball-side surface is focused on the retina of the wearer in principle, but the light beam passing through the portion of the convex region is focused on the object-side surface of the retina. That is, a method of reducing light imaged at the depth of the retina and increasing light imaged in front of the eye is employed, thereby inhibiting the progression of myopia.

Documents of the prior art

Patent document

Patent document 1: U.S. patent application publication No. 2017/0131567 specification

Disclosure of Invention

Problems to be solved by the invention

Light incident on the eyeball is perceived not only in the central visual field including the fovea of the retina, but also in a portion of the peripheral visual field located outside the central visual field.

However, it is known that when light incident on the eyeball is perceived, a bright and dark pattern with a high spatial frequency is highly sensitive in the central field of view, and a bright and dark pattern with a low spatial frequency is highly sensitive in the peripheral field of view. That is, since the peripheral visual field has a lower spatial resolution than the central visual field, the light stimulus as a clue for searching for the focal position is perceived differently from the central visual field.

Therefore, in peripheral vision, it is not possible to perceive that the light transmitted through the 2 nd region is focused on the object side than on the retina, and as a result, there is a possibility that the effect of suppressing the progression of myopia cannot be exerted.

In this regard, it is also contemplated that the lens configuration may be different in the central view corresponding portion and the peripheral view corresponding portion. Specifically, it is conceivable that the shape, the degree, or the like of the 2 nd region is different between a portion corresponding to the central field of view and a portion corresponding to the peripheral field of view, or that a strong field curvature is given to one of the portions. However, when the lens structure is partially different, the surface of the entire lens is not uniform, and the appearance is impaired. In addition, when the eyeball rotates, since the correspondence relationship between the distribution of the lens structure and the line of sight varies, a sufficient effect may not be obtained.

The purpose of the present invention is to provide a technique that enables a spectacle lens to exhibit an effect of suppressing progression of ametropia even in peripheral vision.

Means for solving the problems

The present invention has been made to achieve the above object.

The present invention according to claim 1 is an eyeglass lens comprising:

a 1 st region formed to focus the transmitted light at a predetermined position in the eye, an

A plurality of 2 nd regions formed to focus the transmitted light at a position defocused from the predetermined position,

wherein the plurality of No. 2 regions have negative spherical aberration.

The invention according to claim 2 is the eyeglass lens according to claim 1, wherein,

the plurality of 2 nd regions are configured to have the negative spherical aberration so that light perceived in peripheral vision is recognized as a pseudo spotlight at a position other than the predetermined position.

The 3 rd aspect of the present invention is the eyeglass lens according to the 1 st or 2 nd aspect, wherein,

an estimated value obtained using a gabor function for the transmitted light in the peripheral vision is given to the spherical aberration of the plurality of 2 nd regions so that the estimated value has a maximum value at a position other than the predetermined position.

The 4 th aspect of the present invention is the eyeglass lens according to any one of the 1 st to 3 th aspects, wherein,

an estimated value obtained using a gabor function for the transmitted light in the peripheral vision is given to the spherical aberration of the plurality of 2 nd regions so that the estimated value has a maximum value at a position other than the predetermined position.

The 5 th aspect of the present invention is the eyeglass lens according to any one of the 1 st to 4 th aspects, wherein,

the plurality of 2 nd regions are configured to have the negative spherical aberration such that a position where an outermost ray of the 2 nd region intersects with a ray passing 10% of a radius of the 2 nd region from the outermost portion to an inner side is between the predetermined position and a position defocused from the predetermined position.

The 6 th aspect of the present invention is the eyeglass lens according to any one of the 1 st to 5 th aspects, wherein,

the plurality of 2 nd regions are formed in an aspherical shape having a curvature that is smaller as being farther from the center of the 2 nd region.

The 7 th aspect of the present invention is the eyeglass lens according to any one of the 1 st to 6 th aspects, wherein,

the size and arrangement interval of the plurality of 2 nd regions are formed as follows: at least 3 of the 2 nd regions are arranged within a range of a pupil diameter through which the transmitted light passes, and a figure connecting respective reference points of the 3 2 nd regions is an acute triangle.

The 8 th aspect of the present invention is the eyeglass lens according to any one of the 1 st to 7 th aspects, wherein,

the plurality of 2 nd regions are configured in a hexagonal shape.

The 9 th aspect of the present invention is the eyeglass lens according to any one of the 1 st to 8 th aspects, wherein,

the plurality of 2 nd regions are formed of a multi-layered structure,

the innermost layer in the multilayer structure is a layer having the effect of imparting a defocus degree,

the layer on the outer side of this layer has an effect of imparting negative spherical aberration.

Effects of the invention

According to the present invention, even in peripheral vision, the eyeglass lens can be made to exhibit an effect of suppressing progression of ametropia.

Drawings

Fig. 1 is a front view showing an example of an eyeglass lens according to an embodiment of the present invention.

Fig. 2 is (a) a schematic cross-sectional view showing a path of light passing through the eyeglass lens shown in fig. 1.

Fig. 3 is a schematic cross-sectional view (second) showing a path of light passing through the eyeglass lens shown in fig. 1.

Fig. 4 is a schematic cross-sectional view showing the path of the principal ray of light incident on each segment in the case of the central vision and peripheral vision.

Fig. 5 is an enlarged view illustrating the shape and curvature of a convex region in the eyeglass lens shown in fig. 1.

Fig. 6 is an explanatory view showing a simulated image when light transmitted through the convex region shown in fig. 5 is perceived by the central visual field of the eyeball.

Fig. 7 is an explanatory view showing a simulated image when light transmitted through the convex region shown in fig. 5 is perceived by the peripheral visual field of the eyeball.

Fig. 8 is an explanatory diagram showing the shape of a segment of each eyeglass lens according to the embodiment of the present invention and the comparative example thereof.

Fig. 9 is an explanatory diagram showing a curvature distribution of segments of each eyeglass lens according to an embodiment of the present invention and a comparative example thereof.

Fig. 10 is an explanatory diagram showing an example of a graph of gabor coefficients (estimated values) of the eyeglass lens according to the embodiment of the present invention.

Fig. 11 is an explanatory diagram showing an example of a graph of gabor coefficients (estimated values) of the eyeglass lens according to the comparative example.

Fig. 12 is a side sectional view showing a main-part configuration example of an eyeglass lens according to another embodiment of the present invention.

Detailed Description

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, the following description is only an example, and the present invention is not limited to the exemplary embodiment.

(1) Structure of glasses lens

First, the structure of the eyeglass lens exemplified in the present embodiment will be described.

The spectacle lens exemplified in the present embodiment is an ametropia progression suppression lens that suppresses progression of ametropia of the eye of the spectacle wearer. The ametropia progression suppression lens is configured to have: a 1 st region having a 1 st refractive power based on a treatment method of correcting ametropia of the eye, and a 2 nd region having a refractive power different from the 1 st refractive power, and the ametropia progression suppression lens having a function of focusing at a position other than a retina of the eye to suppress ametropia of the eye.

The ametropia progression suppressing lens includes a myopia progression suppressing lens for suppressing progression of myopia and a hyperopia progression suppressing lens for suppressing progression of hyperopia. In the following description, a near vision development suppression lens is taken as an example.

Fig. 1 is a front view showing an example of a spectacle lens according to the present embodiment. Fig. 2 and 3 are schematic cross-sectional views showing paths of light passing through the eyeglass lens shown in fig. 1.

(Overall Structure)

The eyeglass lens 1 of the present embodiment has an object-side surface and an eyeball-side surface. The "object side surface" is a surface located on the object side when the wearer wears glasses having the spectacle lens 1. In contrast, the "eyeball-side surface" is a surface located on the eyeball side when the wearer wears eyeglasses having the eyeglass lens 1. In the present embodiment, the surface on the object side is a convex surface, and the surface on the eyeball side is a concave surface. That is, the eyeglass lens 1 is a concave-convex lens.

The eyeglass lens 1 is configured to have a lens base material. The lens base material is formed of a thermosetting resin material such as a thiourethane resin, an allyl resin, an acrylic resin, and an episulfide resin. Further, as the resin material constituting the lens base material, another resin material capable of obtaining a desired diopter can be selected. Further, the lens base material may be made of inorganic glass instead of the resin material.

A coating film is formed on at least one of the object-side surface and the eyeball-side surface of the lens base material. Examples of the coating film include a hard coat film and an antireflection film (AR film), but other films may be used.

The hard coat film is formed using, for example, a thermoplastic resin or a UV-curable resin. The hard coat film can be formed by a method of immersing a lens base material in a hard coat solution, spin coating, or the like. By covering the hard coat layer in this manner, durability of the eyeglass lens 1 can be improved.

The antireflection film is obtained by, for example, subjecting ZrO to₂，MgF₂，Al₂O₃The antireflection agent is formed by forming a film by vacuum deposition. By covering such an antireflection film, the image can be seen through the spectacle lens 1.

(convex region)

In the eyeglass lens 1 of the present embodiment, for example, a plurality of convex regions are formed on the object-side surface (convex surface) of the lens base material so as to protrude from the surface toward the object side. Each convex region is formed of a curved surface having a curvature different from that of the object-side surface of the lens base material. When a lens base material having such a convex region is covered with a coating film such as a hard coat film or an antireflection film, a plurality of convex regions are formed on the surface of the coating film in conformity with the convex region of the lens base material. That is, on the object-side surface (convex surface) of the eyeglass lens 1, a plurality of convex regions 6 formed to protrude from the surface toward the object side are arranged in accordance with the thickness of the convex region of the lens base material and the coating film covering the convex region. Here, the case where the plurality of convex regions 6 are arranged on the object side surface is exemplified, but the present invention is not limited to this, and may be arranged on at least one of the object side surface and the eyeball side surface.

As shown in fig. 1, a plurality of convex regions 6 are regularly arranged on the surface of the eyeglass lens 1. In the illustrated example, the plurality of convex regions 6 are locally arranged in the vicinity of the lens center, but the present invention is not limited thereto, and the convex regions 6 may be arranged over the entire surface of the lens or may be arranged in a circumferential shape so as to surround the lens center as long as the convex regions are regularly arranged.

The plurality of convex regions 6 are arranged in independent islands (i.e., arranged in a state of being separated from each other without being adjacent to each other). That is, in the present embodiment, the convex regions 6 are arranged discretely (i.e., discontinuously and dispersedly). Here, although the case where all the convex regions 6 are independent islands is exemplified here, the present invention is not necessarily limited to this, and the convex regions 6 may be arranged so as to include a portion where outer edges of adjacent regions are connected or in contact with each other.

(optical Properties)

In the eyeglass lens 1 having the above-described configuration, the convex region 6 is provided on the surface 3 on the object side, whereby the optical characteristics as described below are realized, and as a result, progression of ametropia such as myopia of the eyeglass wearer can be suppressed.

As shown in fig. 2, in the eyeglass lens 1, light incident on the object-side surface 3 of a region where the convex region 6 is not formed (hereinafter referred to as "base region") is emitted from the eyeball-side surface 4 and focused on the retina 20A of the eyeball 20. That is, the light transmitted through the spectacle lens 1 is focused on the retina 20A of the spectacle wearer in principle. In other words, the curvature of the base area of the eyeglass lens 1 is set according to the way the eyeglass wearer handles to focus on the predetermined position a (i.e., on the retina 20A). Therefore, the base region of the eyeglass lens 1 functions as a "1 st region" which is formed to have the 1 st refractive power based on the processing method of correcting the ametropia of the eye of the eyeglass wearer, and focuses lens transmission light on a predetermined position a (i.e., retina 20A). The term "focus" as used herein means focusing and imaging of light, but is not necessarily imaging without aberration, and may be imaging with spherical aberration or astigmatism. The "focal point" referred to in the present specification means a point recognized as a point where a maximum value is visually obtained.

On the other hand, as shown in fig. 3, in the spectacle lens 1, light incident on the convex region 6 passes from the eyeballThe side surface 4 is emitted and focused at a position (defocused position) closer to the object side than the retina 20A of the eyeball 20. That is, the convex region 6 converges the light emitted from the eyeball-side surface 4 to a position B closer to the object side than the predetermined position a. The convergence position B is based on each of the plurality of convex regions 6 as a position B₁、B₂、B₃、……B_NIs present. Therefore, each of the plurality of convex regions 6 functions as a "2 nd region" formed so that the lens transmitted light is focused at a position B that is separated from the predetermined position a. Hereinafter, the convex region 6 serving as the 2 nd region is also referred to as a "segment".

In this way, the eyeglass lens 1 is basically configured such that the light beam incident from the object-side surface 3 is emitted from the eyeball-side surface 4 and converged at the predetermined position a, and on the other hand, the light beam is converged at the position B (B) closer to the object side than the predetermined position a in the portion where the segment 6 is arranged (B)₁、B₂、B₃、……B_N) To (3). That is, the eyeglass lens 1 has a function of converging light rays at a position B close to the object side, which is different from a light ray converging function for realizing a processing method of the eyeglass wearer. By having such optical characteristics, the eyeglass lens 1 can exhibit an effect of suppressing the progress of ametropia such as myopia of the eyeglass wearer (hereinafter referred to as "myopia suppressing effect")

(2) Outline of peripheral vision

The optical characteristics of the above-described eyeglass lens 1 are mainly optical characteristics in the case where incident light reaches a central visual field including the fovea of the retina after passing through the lens and is perceived in a part of the central visual field. However, the retina of the eyeball also corresponds to peripheral vision. The "peripheral vision" referred to herein is a case where light is perceived in a portion of the peripheral field of view located outside the central field of view.

Fig. 4 is a schematic cross-sectional view showing the path of the principal ray of light incident on each segment in the case of the central vision and peripheral vision.

In many cases, as represented by the example of fig. 4, light that reaches the peripheral visual field 20B enters the eyeglass lens 1 at an angle with respect to light that reaches the central visual field 20C.

When light having an angle with respect to the light reaching the central visual field 20C passes through the eyeglass lens 1 and further passes through the pupil 20D of the eyeball 20, reaches a portion of the peripheral visual field 20B of the retina 20A, and is perceived in the peripheral visual field 20B. The peripheral field of view 20B has a lower spatial resolution than the central field of view 20C. Specifically, the photoreceptor cells in the peripheral field 20B have a resolution of only about 10% to 20% of that in the central field 20C. Therefore, in the peripheral visual field 20B, the light stimulus as a clue for searching for the focal position may be perceived differently from the case of the central visual field 20C.

Therefore, in the peripheral vision, as described above, even if the light is condensed at the position B, the peripheral field of view 20B may not be detected. That is, in the peripheral visual field 20B, since the optical stimulus as a clue for searching for the focal position is different from that in the central visual field 20C, the light transmitted through the segment 6 of the spectacle lens 1 is not perceived to be focused at the position B on the object side than on the retina 20A, and as a result, the effect of suppressing the progression of myopia may not be exhibited.

Here, a difference between the image perceived in the central field of view 20C and the image perceived in the peripheral field of view 20B will be specifically described.

Fig. 5 is an enlarged view showing the shape and curvature of the segment 6 in the eyeglass lens 1.

Here, focusing on the region C in which the segments are arranged in a hexagonal shape as shown in fig. 5, how the light transmitted through each segment 6 in the region C is perceived will be described.

Fig. 6 is an explanatory diagram showing a simulated image when light transmitted through the segment 6 of the eyeglass lens 1 is perceived by the central visual field 20C of the eyeball 20.

In this illustration, when the predetermined position a on the retina 20A is "0D (diopter)", the spectacle lens 1 in which the segment 6 is formed so as to be focused at the position B closer to the object side by "3.4D" than the predetermined position a shows a result of obtaining, by simulation, how the light transmitted through the segment 6 is perceived in the central visual field 20C in a plurality of portions from 3.4D to 0D.

As shown in fig. 6, according to the simulation in consideration of the resolution of the central field of view 20C, the light transmitted through each segment 6 is perceived at the position B (i.e., the position of +3.4D) so that the diameter of the white circle pattern in the figure indicating the perceived state of light is the smallest and the light is perceived as the smallest (see arrow D shown in fig. 6).

Fig. 7 is an explanatory diagram showing a simulated image of light transmitted through the segment 6 of the eyeglass lens 1 when the peripheral visual field 20B of the eyeball 20 is perceived.

In the legend, as in the case of the center field of view 20C described above, simulation results of a plurality of sites between the predetermined position a (0D) and the position B (+3.4D) closer to the object side than the predetermined position a are also shown.

As shown in fig. 7, according to the simulation in consideration of the resolution of the peripheral field of view 20B, unlike the case of the central field of view 20C described above, the most focused light is not sensed at the position B (i.e., the position of + 3.4D). That is, it is understood that the lights transmitted through the segments 6 are not individually perceived, but are perceived as one light after being combined with each other, and are perceived in a manner that the overall perception is blurred.

As described above, the central field of view 20C and the peripheral field of view 20B have different light sensing patterns depending on the resolution. Therefore, even if the segment 6 is formed to exhibit the effect of suppressing myopia for the central visual field 20C, the effect of suppressing myopia is not always exhibited in peripheral vision by this means alone.

In order to exhibit the effect of suppressing myopia also in the peripheral visual field, it is conceivable to make the lens structure of the eyeglass lens 1 different between the portion corresponding to the central visual field 20C and the portion corresponding to the peripheral visual field 20B. Specifically, it is conceivable that the shape, the degree, and the like of the segment 6 are different between the corresponding portion of the central field of view 20C and the corresponding portion of the peripheral field of view 20B, or that a strong field curvature is given to one of the portions. However, when the lens structure is partially different, the surface of the entire lens is not uniform, and the appearance is impaired. In addition, when the eyeball rotates, since the correspondence relationship between the distribution of the lens structure and the line of sight varies, a sufficient effect may not be obtained. That is, it is not preferable to make the lens structure different between the corresponding portion of the central visual field 20C and the corresponding portion of the peripheral visual field 20B. In addition, a mode in which the effect of inhibiting myopia with respect to the central visual field 20C is impaired in consideration of peripheral vision is not preferable.

As a result of intensive studies on this point, the inventors of the present application have conceived the following lens configuration so that the effect of inhibiting myopia in the central visual field 20C can be exhibited remarkably even in peripheral vision without impairing the effect of inhibiting myopia.

For example, in peripheral vision, light is perceived as blurring as a whole due to a difference in resolution from the central field of view 20C. That is, unlike the case of the center field of view 20C, the most focused light is not sensed at the position B (i.e., the position of + 3.4D). However, it is conceivable that even if the most focused light is not sensed at the position B, as long as the most focused light is sensed at least at a position closer to the object side than the position a (i.e., the position of 0D) (for example, see arrow E shown in fig. 7) (i.e., as long as the diameter of the white circle figure in the figure representing the perceived state of light is smallest), a significant myopia-suppressing effect can be exerted. In the peripheral vision, in order to sense the light condensation at least at a position closer to the object side than the position a, the superimposition of the blurred images of the low-resolution spatial resolution in the peripheral field of view 20B may be used. That is, in peripheral vision, light transmitted through each segment 6 is perceived as a blurred image due to low resolution, but if light energy is increased due to the overlapping portion of the blurred images, it can be perceived as if there is a focal point at the position of the overlapping portion. Hereinafter, the case where the focused spot is virtually perceived at a position other than the optical focal position by the overlapping of the blurred images is simply referred to as "pseudo focusing".

In order to more effectively generate such pseudo-condensed light, each of the segments has a negative spherical aberration characteristic such that the light energy at the edge portion of the blurred image of each segment is higher than that at the center portion of the blurred image.

That is, the inventors of the present application have conceived the following lens configuration in order to achieve the effect of suppressing progression of ametropia even in the case of peripheral vision having a spatial resolution of low resolution: each of the plurality of segments 6 is given a negative spherical aberration so that light perceived in peripheral vision is recognized as a pseudo spotlight located at a desired position (i.e., a position other than the focal position a on the retina 20A).

(3) Segmented spherical aberration

Next, the spherical aberration of the plurality of segments 6 in the eyeglass lens 1 of the present embodiment will be described.

The spherical aberration is a phenomenon in which the position of the light beam is different in the optical axis direction depending on the distance from the center of each segment 6. In particular, when the light rays transmitted through the near edge portion are on the side farther from the eyeglass lens 1 in the condensed position in the eye with respect to the light rays transmitted through the central portion of the segment 6 in the condensed position in the eye, it is said to have "negative spherical aberration".

When having spherical aberration, the density of the light emitted from the segment 6 becomes uneven. In particular, on the side farther from the eyeglass lens 1 than the paraxial light converging position, the light beam becomes dense at the edge portion of the light flux, and a ring-shaped region with high light energy appears (for example, see (d) and (e) of fig. 6).

When such spherical aberration is present, rays having different distances from the center of the segment 6 may intersect each other at a point distant from the optical axis or the principal ray of the segment 6. That is, the annular regions may overlap each other. In this case, a region where the light energy is particularly high appears in the light beam. In this way, if the light energy is increased by the overlapping portion of the annular regions, it is possible to sense that the spot appears to be concentrated at the position of the overlapping portion, that is, pseudo-concentration can be generated.

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

In order to impart negative spherical aberration to each segment 6, one method is to make the convex shape of the segment 6 an aspherical shape. Specifically, negative spherical aberration can be given by setting the aspherical shape such that the curvature of the convex surface becomes smaller as the distance from the center of the segment 6 becomes longer.

(4) Configuration of segments

As described above, the pseudo-spot light is caused by overlapping of the light beams of the plurality of segments 6. Therefore, it is preferred that the spectacle lens 1 comprises a plurality of segments 6 within the pupil. Specifically, it is preferable that the size and arrangement interval of each segment 6 are formed as follows: at least 3 segments of the plurality of segments 6 are arranged within the range of the pupil diameter through which transmitted light passes, and a figure connecting respective reference points of the 3 segments 6 is an acute triangle. Here, the reference point of the segment 6 is a point that is used as a reference after the position where the segment 6 is arranged is determined. For example, when the segment 6 has a circular shape in a plan view, the center point of the segment 6 may be a reference point.

To achieve such a configuration, it is most preferable that the plurality of segments 6 are arranged in a hexagonal configuration (particularly, a hexagonal close-packed configuration).

In such a spectacle lens 1, it is possible to verify (estimate) whether or not each segment 6 generates pseudo-spotlight by, for example, the method described below.

Human visual fields are recognized by similar actions to the gabor transform (ref.: J. Daugman, "expression and degradation in visual coding by oriented neural fields", trans. on biological Engineering, Vol.36, No.1, pp.107-114 (1989)). From this point, it is conceivable that how light is perceived in the field of view of a person can be verified (evaluated) to some extent by employing an evaluation value of a gabor function shown by the following equation (1). In addition, in equation (1), let x be the horizontal direction coordinate on the retina, y be the vertical direction coordinate on the retina, and the units are all mm. In this example, gabor functions in the x direction are illustrated by way of example, but gabor functions in the y direction or an intermediate direction may also be used.

[ equation 1]

In the case of estimation using a gabor function, for example, the gabor function shown in the above equation (1) may be convolved with a geometric optical point (a point which does not take into account the spatial resolution of the human visual field), the maximum value of the result of the convolution may be used as a gabor coefficient (that is, an estimated value using the gabor function), and the estimated value may be used for estimation of whether or not pseudo-spotlight is generated. The gabor coefficient used for estimation corresponds to an estimated value of contrast for human visual recognition. Specifically, in the above equation (1), the calculation is performed with a being 0.015 in the central field of view and the calculation is performed with a being 0.105 in the peripheral field of view, the value at the best focus position is normalized to the value 1, and the gabor coefficient (estimated value) is displayed on the graph. As described in detail below, the graph may be considered to be made: the horizontal axis uses the distance (defocus amount, unit: diopter) between the predetermined position a on the retina and the position B at which each segment 6 is focused, and the vertical axis uses the gabor coefficient (estimated value using gabor function, unit: dimensionless amount).

When such a graph is created, when pseudo-convergence occurs between the segments 6 in peripheral vision, an estimated value obtained by using a gabor function for light transmitted through the segments 6 has a maximum value at a position other than the predetermined position a (0D). Therefore, in other words, it is possible to impart spherical aberration to each segment 6 and arrange each segment 6 so that the eyeglass lens 1 in which the segment 6 is arranged generates pseudo-spotlight at a position other than the predetermined position a when, on a graph which is an estimation result using the gabor function, an estimated value obtained using the gabor function for light transmitted through each segment 6 in peripheral vision has a maximum value at a position other than the predetermined position a (0D).

More preferably, the maximum value is a maximum value. However, the maximum value does not necessarily have to be a maximum value, and if the maximum value has a sufficient size, the maximum value is recognized as a pseudo-spotlight even if the maximum value is not the maximum value. For example, the maximum value may have a value larger than the intermediate value between the maximum value and the minimum value.

[ examples ]

The present invention will be described in more detail below with reference to examples. Here, the examples will be described and comparative examples thereof will be briefly described. In the examples and comparative examples, estimation results obtained using gabor functions are also described. The present invention is not limited to the embodiments described below.

(examples)

As an example, the eyeglass lens 1 configured with a plurality of segments 6 is formed as follows: the diameter D of each segment 6 is 0.8mm, the interval L between adjacent segments 6 is 1.05mm, the area ratio K of the segments 6 is 0.5, and the degree P given to each segment 6 is 3.4D.

In the segment 6, the radius of curvature r is 177mm, the conic coefficient k is 0, and the quartic aspherical coefficient a is-8.17 × 10^-4The segment 6 is configured to have a basic shape with the following values: a drooping amount Z with respect to a distance h from the center of the segment calculated according to the following equation (2); and a constant term for making the boundary between the segment and the basic shape continuous.

[ equation 2]

Fig. 8 is an explanatory diagram showing the shape of a segment of each eyeglass lens of the embodiment.

In the figure, the sectional shape of the segment 6 (i.e., the shape obtained by adding the sag amount Z calculated according to the above equation (2) to the base shape) in the eyeglass lens 1 according to the embodiment is shown by a solid line.

In order to manufacture the spectacle lens 1 having such a structure, first, a lens base material is molded by a known molding method such as injection polymerization. For example, a lens base material having a convex region on at least one surface can be obtained by performing molding by injection polymerization using a molding die having a molding surface with a plurality of concave portions. In this case, in order to conform to the use described above, a molding die having a plurality of concave portions formed therein may be used.

After obtaining the lens base material, a coating film such as a hard coat film or an antireflection film is formed on the surface of the lens base material as necessary. The coating film can be formed by a known film forming method as described above.

By the manufacturing method in this order, the eyeglass lens 1 of the embodiment can be obtained.

Fig. 9 is an explanatory diagram showing a curvature distribution of segments of the eyeglass lens of the embodiment.

In the figure, the curvature distribution of the segment 6 (i.e., the curvature distribution of the aspherical shape) in the eyeglass lens 1 of the embodiment is shown by a solid line.

As shown in fig. 9, with the eyeglass lens 1 of the embodiment, the curvature in the vicinity of the center portion of the segment 6 is 5.6[1/M ], whereas the curvature in the vicinity of the outermost portion of the segment 6 becomes smaller to 4.1[1/M ].

According to the above segment 6, negative spherical aberration is generated, whereby the position where the light ray passing through the outermost portion of the segment 6 intersects with the light ray passing through 10% of the radius of the segment 6 from the outermost portion to the inner side is located anterior 1.7D from the predetermined position a (i.e., retina 20A), i.e., at an intermediate point between the retina 20A and the focal position B of the segment 6 defocused from the retina 20A.

Fig. 10 is an explanatory diagram showing an example of a graph of gabor coefficients (estimated values) of the eyeglass lens 1 according to the embodiment. In the graph of this illustration, the horizontal axis takes the distance (defocus amount) between the predetermined position a (0D) on the retina and the position B (3.5D) at which each segment 6 is focused, and the vertical axis takes the gabor coefficient (estimated value using the gabor function), and represents the gabor coefficient (estimated value) normalized to 1 at the best focus position. In the graph, the gabor coefficient calculated in consideration of the resolution of the central view field 20C is indicated by a solid line, and the gabor coefficient calculated in consideration of the resolution of the peripheral view field 20B (that is, the gabor coefficient in the case of peripheral vision) is indicated by a broken line.

As can be seen from the graph shown in fig. 10, in the peripheral vision indicated by the broken line, the gabor coefficient has a maximum value at the point of 1.7D. That is, in the spectacle lens 1, each segment 6 generates pseudo light concentration at a position other than the predetermined position a on the retina, and as a result, it is confirmed that the effect of suppressing myopia in the central visual field 20C is not impaired, and the effect of suppressing myopia can be exhibited even in the case of peripheral vision.

Comparative example

Here, the spectacle lens of the comparative example will be briefly described. The eyeglass lens of the comparative example is obtained by changing the term of the fourth-order aspherical coefficient a in equation (2) to a value of 0, based on the shape described in the above-described embodiment. That is, the segment in the eyeglass lens of the comparative example has a spherical shape (see the broken line shown in fig. 8 and 9).

Fig. 11 is an explanatory diagram showing an example of a graph of gabor coefficients (estimated values) of the eyeglass lens according to the comparative example. In the graph of the legend, the horizontal axis, vertical axis, solid line, broken line, and the like are the same as in the case of the graph shown in fig. 10.

As can be seen from the graph shown in fig. 11, in the peripheral vision indicated by the broken line, the gabor coefficient has a maximum value at the predetermined position a (0D). That is, the spectacle lens of the comparative example does not generate pseudo focusing at a position other than the predetermined position a (0D) because the segment does not have spherical aberration. Therefore, in the spectacle lens of comparative example 1, the effect of suppressing myopia cannot be exhibited in the case of peripheral vision.

(modification example etc.)

While 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-described exemplary disclosure, and various modifications can be made without departing from the scope of the invention.

Fig. 12 is a side sectional view showing a main-part configuration example of an eyeglass lens according to another embodiment of the present invention.

The illustrated eyeglass lens is configured as follows: since the substrate 11 is formed in an aspherical shape in stages, the aspherical layer 12 is provided on the substrate 11 having a defocus degree. For example, the substrate 11 may also serve as a resin lens substrate by injection molding, and the aspherical layer 12 may also serve as a hard coating film. By using such a configuration, the adjustment of the myopia suppressing effect corresponding to the individual can be easily performed.

That is, the segment having negative spherical aberration may be constituted by a multilayer structure. At this time, the innermost layer (specifically, the layer composed of the base material 11) in the multilayer structure becomes a layer having an action of imparting defocus degrees, and the layer further to the outside than the layer (specifically, the layer composed of the aspherical layer 12) becomes a layer having an action of imparting negative spherical aberration.

In addition, for example, in the above disclosure, the spectacle lens 1 having the configuration in which the convex region 6 is provided on the object side surface 3 is exemplified, but the present invention can be applied to spectacle lenses having other configurations. That is, the present invention is configured to include: a 1 st region formed to condense transmitted light at a predetermined position; and a plurality of 2 nd zones formed as an eyeglass lens focused at a defocus position different from that of the 1 st zone, can be applied not only to a lens structure having a convex zone 6 on the lens surface but also to a lens structure having a smooth lens surface.

In addition, for example, in the above disclosure, an example is mainly given in which the eyeglass lens is a myopia progression suppressing lens, but the present invention can also be applied to a hyperopia progression suppressing lens.

For example, in the above disclosure, the case where the convex regions (segments) 6 are arranged in a hexagonal shape is mainly given as an example, but the present invention is not limited to this. That is, in the present invention, even in an arrangement other than the hexagonal arrangement, each convex region (segment) may be arranged so as to generate pseudo light condensation in peripheral vision.

Description of the reference numerals

1: a spectacle lens; 3: a surface on the object side; 4: an eyeball-side face; 6: convex regions (segments); 11: a substrate; 12: an aspherical layer; 20: an eyeball; 20A: a retina; 20B: a peripheral field of view; 20C: a central field of view.