JP2023114018A - spectacle lens - Google Patents

Abstract

To provide a spectacle lens with improved wearing comfort, which has two areas with different focal lengths, a first area having a given refractive power added for refractive correction and a second area(s) having different refractive power from that of the first area and being shaped like a single ring or multiple concentric rings.SOLUTION: A spectacle lens provided herein has a first area 13 having a given refractive power added for refractive correction and concentric second areas 14A-14C having different focal length from that of the first area 13. The second areas 14A-14C are aspherically configured to form rings.The second areas 14A-14C are designed such that a focal depth is extended by astigmatism.SELECTED DRAWING: Figure 2

Description

The present invention relates to a spectacle lens having two different focal length regions: a first region added with a predetermined refractive power for refractive correction and a second region that does not contribute to refractive correction. It is a thing.

Conventionally, there are Fresnel lens-shaped lenses. A Fresnel lens is a lens with a sawtooth cross section in which the lens surface is divided into concentric areas to reduce the lens thickness (flesh), and has been used for magnifiers and efficient diffusion of lighting. In addition to magnifiers, there are also cases of use for treatment of progression of refractive error, such as in Patent Document 1. The lens of Patent Document 1 has a concentric second refractive area that is out of focus with respect to the first refractive area that is in focus, and is used to suppress progression of myopia and hyperopia.

Patent No. 4891249

However, since the lens of Patent Document 1 has a Fresnel lens shape and a clear step is formed at the boundary between the first refraction area and the second refraction area, the wearing feeling is not good. Therefore, spectacles having at least two focal length regions: a first region added with a predetermined refractive power for refractive correction and a second region having a refractive power different from that of the first region 2. Description of the Related Art It has been desired to improve wearing comfort in spectacle lenses in which the second region is in the shape of a single ring or a plurality of concentric rings.

In order to solve the above problem, means 1 provides spectacles comprising a first region to which a predetermined refractive power for refractive correction is added and a second region having a different focal length from the first region. In the lens, the second region is configured in a ring-shaped aspherical shape, and the depth of focus of the second region is extended by astigmatism.
Such a lens for spectacles can eliminate the stepped shape that is a problem with a Fresnel lens, and can provide a lens that is easy to wear.

The "first region" may be spherical or aspherical, while the "second region" is aspherical. This is because the first region and the second region having different curvatures cannot be connected without steps unless they have an aspherical shape.
The number of ring-shaped second regions may be one or plural.
The second area is an area where the depth of focus is extended relative to the first area due to astigmatism. An outline of the depth of focus will be described based on FIG. FIG. 1 is a simulation in which the optical paths of light rays passing through the spectacle lens 11 between the spectacle lens 11 pertaining to the present invention and the eyeball 12 of the wearer who wears the spectacle lens are developed in a cross section passing through the optical axis of the eyeball 12. It is a diagram. (*Figure 1 should also be the first page of my resume.) In the first area 13, to which a predetermined refractive power is added for refractive correction, it is possible to focus on the retina. can. On the other hand, since the second region 14 is given a refractive power different from that of the first region 13, the light beam passing through the second region 14 and directed toward the retina has a depth of focus due to astigmatism.
In FIG. 1, the second area 14 has a positive refractive power relative to the first area 13 as an example, so the light rays passing through this area have an extended depth of focus inside the retina. state. A focal range in which the point spread range on the image plane orthogonal to the light ray is smaller than a certain range is called the depth of focus here. Here, since a relatively positive refractive power is given, the focus is focused inside and the depth of focus is extended inside the retina. In some cases, the depth of focus may be extended outside the retina.
In this way, by arranging a plurality of second regions 14 concentrically with respect to the first region 13 so that the depth of focus extends inward from the retina, an effect of suppressing the progression of myopia can be expected. Also, although not shown, if a negative refractive power is given to the second area 14 relative to the first area 13, the depth of focus will be extended outside the retina. Even in such a case, by arranging a plurality of second regions 14 concentrically with respect to the first region 13, an effect of suppressing progression of hyperopia can be expected.

Further, in the means 2, the ring-shaped second region is formed in a belt shape of equal width.
The outer contour of the strip is circular, and the second region is surrounded by a circle at the boundary between the inner and outer sides. As a result, various unnecessary aberrations that may occur in the lens are less likely to occur.
Further, in means 3, the width of the ring-shaped second region is set to 0.8 mm or more and 3.0 mm or less.
If the second region is thinner than 0.8 mm, the human eye may not be able to perceive that the depth of focus is extended, while if it is not 3.0 mm or less, the refractive correction of the first region is hindered. It is from.
Further, in means 4, the ring-shaped second region is arranged outside the circular region with a radius of 3 mm around the center of the lens.
This is because the vicinity of the lens center should be secured as an area for refractive correction.

In means 5, a plurality of the ring-shaped second regions are concentrically spaced apart.
Further, in means 6, the widths of the plurality of ring-shaped second regions are not the same.
Further, in means 7, the intervals between the plurality of adjacent ring-shaped second regions are not the same.
Further, in means 8, the curvatures of the plurality of adjacent ring-shaped second regions are not the same.
Further, in means 9, the center position of the second ring-shaped region is made to coincide with the optical center of the lens.
As a result, the second regions are arranged in multiple stages outward from the lens center direction with respect to the first region in most parts of the user's visual field, and the first regions and the second regions are arranged alternately. A region through which the line of sight passes is formed.
2(a) and 2(b) are a spectacle lens 11 of an embodiment as an example belonging to the present invention. An outline of the means 5 to 9 will be explained based on FIGS. 2(a) and 2(b). 2(a) and 2(b) will be described with the same reference numerals as in FIG. In addition, in FIG. 2A, the second area is represented by solid color for the sake of convenience in order to distinguish between the first area and the second area. Based on the first region 13 to which a predetermined refractive power for refractive correction is added, as an example here, three ring-shaped second regions 14 are arranged so that the center of the concentric circles becomes the optical center. ing. The ring-shaped second regions 14 are preferably spaced apart in this manner except for the center of the spectacle lens 11 .
When each ring-shaped second region 14 is a ring 14A, a ring 14B, and a ring 14C in order from the center side, the widths of the rings 14A to 14C may be the same or different. should be wider toward the outside. The width of each ring 14A-14C is preferably 0.8 mm or more and 3.0 mm or less as described above.
The distance between the rings 14A to 14C, that is, the distance between the first regions 13 sandwiched between the rings 14A and 14B or between the rings 14B and 14C may be the same or different. The wider the outside, the better. The interval is preferably 0.8 mm or more and 3.0 mm or less.
It is said that the human pupil diameter varies between approximately 2.0 and 8.0 mm depending on the brightness of the surroundings. By making the ring or the ring interval small with respect to the diameter of the light beam incident on the pupil, refractive correction accompanied by extension of the depth of focus becomes possible, and visibility is improved.
The radii of curvature of the rings 14A to 14C may be the same or different, and if they are different, it is preferable that the radii of curvature are larger toward the outside or smaller toward the outside. If the feeling of wearing is emphasized, the difference in radius of curvature from the first region 13 should be smaller toward the inside, and if the effect of suppressing progression of myopia is to be enhanced, the radius of curvature should be smaller than that of the first region 13 toward the inside. should have a larger radius of curvature. The relationship among the rings 14A to 14C having a large radius of curvature is the same even when four or more ring-shaped second regions 14 are provided.

Further, in the means 10, the first region has an aspherical shape.
In the above description, the condition for the second area is an aspherical shape, but the first area is not subject to such limitations. However, it is better if the first region is also aspherical.
Further, in means 11, the second area has astigmatism of 0.5D or more as an absolute value with respect to the first area.
This is because when the second region has astigmatism of 0.5D or more with respect to the first region, it is possible to give the wearer's eyeball a sufficient depth of focus.
In means 12, the ring-shaped second region has a portion in which the curvature in the cross-sectional direction passing through the center position of the ring varies depending on the phase in the circumferential direction of the ring shape.
With this, it is possible to adjust the optimal appearance depending on the direction (azimuth), such as a direction (azimuth) where it is desirable to make the depth of focus smaller, or a direction (azimuth) where it is desirable to make it more difficult to see by increasing the depth of focus. can be done. Curvature is, in other words, the refractive power imparted to the lens. This is because the refractive power has a curvature (curvature radius) as a parameter. The phase is preferably indicated by an angle (azimuth) with a certain direction as a reference. The change is, for example, changing the curvature set in the second area to the curvature set in the first area. One of the reasons for doing so is that the change can be expected to improve the feeling of wearing.
Another reason for this configuration is as follows. For example, as shown in FIG. 3(a), the upper half of the ring-shaped second region (rings 14A to 14C) is often placed just in front of the line of sight due to slipping of the glasses when worn. . If the second area is arranged in front of the line of sight, for example, when the depth of focus is on the plus side, the visual state will result in an adjustment less than the corrected predetermined refractive power.
Therefore, in that case, as shown in FIG. Even if the is placed just in front of the line of sight, it can be viewed with the correct adjustment. In FIG. 3B, the closer the absolute value of the curvature is to the first region or the same color as the first region, the lighter the color, and the farther the absolute value of the curvature is from the absolute value of the curvature of the first region, the darker the color. The second area is represented by gradation so that It is preferable that the curvature is such that the vicinity of the uppermost portion, which is most likely to be arranged in front of the pupil, is closest to the first region or is the same as the first region.
Also, for example, as shown in FIG. 4A, the upper halves of all rings 14A-14C may be configured with a curvature close to or the same as the first region. Also, instead of changing the curvature of only the upper half of the rings 14A to 14C, the changed curvatures of the inner and outer rings 14A and 14B are arranged at different phase positions, respectively, as shown in FIG. (ie, may vary with orientation). In FIG. 4B, the curvatures are arranged in four directions with a phase shift of 90 degrees (azimuth directions rotated by 90 degrees with respect to a certain direction), and the inner and outer rings 14A and 14B are shifted by 45 degrees. Although they are arranged so as to have phases, curvatures with varied curvatures may be arranged at positions having other numbers. The arrangement of the inner and outer rings 14A, 14B is not limited to this either. FIG. 4B shows that the fragmented portion has the same curvature as the first region, but the curvature of the fragmented portion can be freely set and does not have to be the same curvature as the first region. . Moreover, it is not necessary to provide 13 regions between 14A and 14B. The gradation of the second area in the drawing of FIG. 4A is also synonymous with the case of FIG. 3(b).

Further, in the means 13, the ring-shaped second region is connected to the first region adjacent in the cross-sectional direction passing through the center position of the ring without steps.
Since the first area and the second area have different refractive powers, they also have different curve shapes. Therefore, by connecting two areas with different curve shapes without steps, the stepped shape of the lens surface is eliminated, and a lens with good wearability can be provided.
"Connection without steps" means not only that the curve of the first region and the curve of the second region are smoothly connected, but also that the curves of the first region and the curve of the second region intersect and become discontinuous, for example. may be connected to
Further, in means 14, the ring-shaped second region has a slope at least at an inner boundary position where the second region is connected to the first region in a cross-sectional direction passing through the ring center position. is the same as the slope of the region of
As a result, the curve of the first region and the curve of the second region are smoothly connected at least at the inner boundary of the second region, so that a lens with good wearability can be provided.
Further, in means 15, the ring-shaped second region has a slope at an outer boundary position where the second region is connected to the first region in a cross-sectional direction passing through the ring center position. Made it the same as the slope of the region.
As a result, the curve of the first area and the curve of the second area are smoothly connected at the outer boundary of the second area, so that a lens with good wearability can be provided.
In means 16, the second area is provided on the rear surface of the lens.
Further, in means 17, the first region is provided on the rear surface of the lens.
Further, in means 18, the spectacle lens according to any one of means 1 to 17 is a lens for suppressing progress of myopia.
In means 19, the spectacle lens according to any one of means 1 to 17 is a hyperopia progression suppressing lens.
Means 18 and 19 give an example of a specific application of the spectacle lens of the present invention.

The inventions shown in the above means can be combined arbitrarily. For example, a configuration may be adopted in which at least part of the configuration of at least one invention after the means 2 is added to all or part of the configuration of the invention shown in the first means. In particular, it is preferable to add at least a part of the configuration of at least one invention after the second means to the invention shown in the first means. Also, arbitrary configurations may be extracted from the inventions shown in means 1 to 19, and the extracted configurations may be combined. The smoothness of connection in the means 13 to 15 may also be adjusted as appropriate. The applicant of this application intends to obtain rights to inventions including these configurations.

According to the spectacle lens of the present invention, it is possible to provide a lens that is easy to wear because the stepped shape, which is a problem with Fresnel lenses, is eliminated.

Explanatory drawing explaining the outline|summary of the focal depth in the spectacle lens of this invention. (a) is a rear view, and (b) is a vertical cross-sectional view at the optical center for explaining the arrangement position of the second region of the spectacle lens of Embodiment 1. FIG. (a) is an explanatory view of a state in which the upper half of the ring-shaped second region is positioned just in front of the line of sight due to slipping of the glasses when worn, and (b) is an upper half of the ring-shaped second region. 11 is an explanatory diagram of a state where the glasses slip down in the same manner as in (a) when the depth of focus of is close to the first region or the curvature is the same as that of the first region. When a plurality of ring-shaped second regions are arranged concentrically, the upper halves of all the ring-shaped second regions are configured to have a curvature close to or the same as that of the first region. Explanatory diagram for explaining. When a plurality of ring-shaped second regions are arranged concentrically, the curvature portion of the first region set in the second region is shifted between the inner and outer ring-shaped second regions. Explanatory diagram of the state where it is. FIG. 4 is a cross-sectional view for explaining the distance from the optical center to the second region in the cross section at the optical center in Embodiment 1; 4A to 4C are explanatory diagrams for explaining a method of connecting the first region and the second region in the first embodiment; FIG. (a) to (d) are explanatory diagrams for explaining a method of connecting a first region and a second region in the second embodiment. (a) to (c) are explanatory diagrams for explaining a method of connecting a first region and a second region in a comparative example. In the third embodiment, the second concentric regions are expressed by gradation so that the absolute value of the curvature according to the azimuth angle becomes darker as the value is farther from the absolute value of the curvature of the first region. Image diagram of the arrangement of . FIG. 11 is an image diagram of the arrangement of concentric second regions in which the second regions are expressed by gradation so that the absolute value of the curvature becomes darker the farther the value of the curvature is from the absolute value of the curvature of the first region in the fourth embodiment. FIG. 2 is an explanatory diagram for explaining the positional relationship between spectacle lenses and eyeballs in Example 1; In Example 1, (a) is a graph explaining the optical characteristics of the refractive power of the spectacle lens, and (b) is a graph explaining the optical characteristics of the prism power of the spectacle lens. In Example 2, (a) is a graph explaining the optical characteristics of the refractive power of the spectacle lens, and (b) is a graph explaining the optical characteristics of the prism power of the spectacle lens. In Example 3, (a) is a graph explaining the optical characteristics of the refractive power in the upward direction of the spectacle lens, and (b) is a graph explaining the optical characteristics of the prism power in the upward direction of the spectacle lens. In Example 3, (a) is a graph for explaining the optical characteristics of the refractive power in the downward direction of the spectacle lens, and (b) is a graph for explaining the optical characteristics of the prism power in the downward direction of the spectacle lens. In Example 4, (a) is a graph explaining the optical characteristics of the refractive power in the upward direction of the spectacle lens, and (b) is a graph explaining the optical characteristics of the prism power in the upward direction of the spectacle lens. In Example 4, (a) is a graph explaining the optical characteristics of the refractive power in the downward direction of the spectacle lens, and (b) is a graph explaining the optical characteristics of the prism power in the downward direction of the spectacle lens. In the comparative example, (a) is a graph for explaining the refractive power optical characteristics of the spectacle lens, and (b) is a graph for explaining the prism power optical characteristics of the spectacle lens.

Hereinafter, specific embodiments of spectacle lenses will be described with reference to the drawings.
(Embodiment 1)
The spectacle lens 11 of Embodiment 1 is produced by cutting a semi-finished blank as a precursor lens by inputting processing data into an NC device, which is a processing device with a built-in computer, and controlling the computer with a program. be done. As shown in FIGS. 2 and 5, the spectacle lens 11 is an SV (single vision) lens having a meniscus lens shape with a circular outer shape and is called a so-called round lens before being framed. The spectacle lens 11 is cut into a frame shape (target shape) according to a user's request by a manufacturer or an optician. The spectacle lens 11 of Embodiment 1 has, on the inner surface (concave surface), a first region 13 provided with a corrective power according to the prescription of the wearer, and three concentrically arranged ring-shaped regions having an extended depth of focus. A second region 14 is formed. The three ring-shaped second regions 14 are called rings 14A, 14B, and 14C in order from the inner side near the optical center.

An example of calculating the processing data of the spectacle lens 11 and processing the spectacle lens is shown. Data related to lens power specific to the wearer, such as S power and prism, are set according to the wearer.
Basically, the surface (convex surface) is a spherical surface, and the inner surface (concave surface) is the shape data of the first region 13, which is the correction zone according to the user's prescription, and the extension zone whose optical center is the center of a circular ring. Processing is performed by an NC device using processing data obtained by synthesizing the shape data of a certain second region 14 .
When processing the spectacle lens 1, a sag amount is given in a straight line direction perpendicular to the surface passing through the geometric center of the lens surface. That is, the processed data is sag data. FIG. 5 is a cross-sectional view taken along a straight line passing through the optical center. When viewed from this direction, the three ring-shaped second regions 14 arranged concentrically are alternately arranged with the first regions 13 . As shown in FIG. 5, in three-dimensional coordinates indicating the processing position, the thickness direction of the lens is the Z axis, the vertical direction when the lens is worn is the Y axis direction, and the depth direction orthogonal to the Y axis direction is the X axis. direction.
An example of a method of designing processing data when processing the first region 13 and the second region 14 arranged in this manner will be described below with numbering. Although the ring 14A at the position closest to the optical center in FIG. 5 will be described below as an example of calculation, similar calculations are performed for other positions with only different distances from the center.
(1) The distance in the radial direction d from the lens optical center is expressed as d=sqrt(X ² +Y ² ). According to this formula, the distance from the lens optical center to the ring 14A is obtained. The distances are the distance d1 and the distance d2 to two boundaries in the width direction that intersect the ring 14A.
(2) First, the sag value of the first region 13, which is the correction zone, is obtained. The sag value is a function of the distance d from the center and the curvature Cc for providing the refractive power necessary for refractive correction at the lens optical center. The sag value Zc of the first region 13 can be generalized as shown in Equation 1 below. In Equation 1, the first half of f(Cc, d) represents the curve of the cross section passing through the optical center of the spherical surface with curvature Cc, and the second half of f(Cc, d) is the optionally added aspheric amount. A1-A4 are arbitrary aspheric coefficients.

(3) Next, the sag value of the ring 14A, which is the extension zone, is obtained in the same manner as above. Unlike the first region 13, the ring 14A has a curvature and aspheric coefficients of Cf and B1 to B4, respectively. Similar to the sag value Zc of the first region 13, the sag value Zf of the ring 14A can be generalized as shown in Equation 2 below. As in Equation 1, the first half of f(Cf, d) represents a curve of a cross section passing through the optical center of a spherical surface with curvature Cf, and the second half of Cf is an optionally added aspherical amount. B1-B4 are arbitrary aspheric coefficients. Cf is Cc>Cf if the ring 14A has a depth of focus on the positive refractive power side relative to the first region 13, and has a depth of focus on the negative refractive power side. For example, Cc>Cf.

(4) Next, a method of connecting the first region 13 and the ring 14A, which is the second region 14, will be described with reference to the drawings.
Consider a case where a curve R2 is joined to a region FE in which a ring 14A is set based on a curve R1 as shown in FIG. 6(a). The boundary on the optical center side of the area FE is at position d1, and the outer boundary is at position d2. Since the curves R1 and R2 have different curvatures, they do not coincide with each other. As shown in FIG. 6(b), the curve R2 is moved parallel to the curve R1 so that it approaches the curve R1 and intersects the curve R1 at the position d1 to match the coordinates of both. Next, the curve R2 is tilted (rotated) with the position d1 as a reference, and the curve R2 is made to intersect the curve R1 at the position d2 so that the coordinates of both are matched (the state of FIG. 6(c)). As a result, a different curve R2 can be connected without steps to the lens surface based on the curve R1. A sag value is determined so that the first region 13 and the ring 14A form a curved surface as shown in FIG. By designing the ring 14A to tilt in all directions from the optical center, the ring 14A becomes aspherical.
On the other hand, if such a connection method is not adopted, for example, as shown in FIGS. . FIG. 8 shows a state in which a step has been created at a distance d1, which is the inner boundary line of the ring 14A.

Based on such a design concept, a specific method for determining the Z coordinate corresponding to the XY coordinate in the cross-sectional direction passing through the optical center will be described.
a) When d<d1 or when d>d1 Z=f(Cc, d), that is, the sag value is expressed by the above equation (1).
b) When d1 ≤ d ≤ d2 The sag value is given by the following equation (3). Equation 3 is the sum of equation 2 and two equations that cancel it. In Equation 3, the first term is Equation 2 and represents the shape of a curved surface (a spherical surface if there is no aspherical coefficient) with a curvature Cf. The second term is a term that cancels the sag difference between the curved surface with the curvature Cf and the curved surface with the curvature Cc at the point d1. The third term is a term that cancels the difference between the slope of the curved surface with the curvature Cf and the slope of the curved surface with the curvature Cc in the d1-d2 section.

In Embodiment 1, the back surface of the spectacle lens 11 is processed based on the formula (3). In such a spectacle lens 1, since there is no step at the boundary between the first refraction zone and the second refraction zone, the wearing comfort is improved.

(Embodiment 2)
Embodiment 2 is an example of calculating the processing data of spectacle lens 11 by a design method different from Embodiment 1 (in particular, a method of connecting first region 13 and second region 14).
In the second embodiment, since the above (1) to (3) are the same as those in the first embodiment, description thereof will be omitted, and only points different from the first embodiment will be described. The contents corresponding to the following description of (4) in Embodiment 1 will be described below as (5).
(5)
Consider a case where a curve R2 is joined to a certain area FE in which a ring 14A is set based on a curve R1 as shown in FIG. 7(a). The boundary on the optical center side of the area FE is at position d1, and the outer boundary is at position d2. Since the curves R1 and R2 have different curvatures, they do not coincide with each other. Similar to FIG. 6(b) of Embodiment 1, the curve R2 is moved parallel to the curve R1 to approach it, and is crossed at the position d1 to match the coordinates of both (the state of FIG. 7(b)). Next, the curve R2 is tilted (rotated) with the position d1 as a reference as indicated by an arrow to match the tilt of the curve R1 at the position d1 (or near the position d1) (state shown in FIG. 7(c)). As a result, the curve R2, which is the curve of the area FE, is smoothly connected to the curve R1 on the optical center side (inner side). By designing the ring 14A to tilt in all directions from the optical center, the ring 14A becomes aspherical.
Then, as shown in FIG. 7D, the curve R1 and the curve R2 are cut at the position d2, and the curve R1 is connected to the curve R2 of the area FE at the position d2.

Based on such a design concept, a specific method for determining the Z coordinate corresponding to the XY coordinate in the cross-sectional direction passing through the optical center will be described.
b) When d<d1, Z=f(Cc, d), that is, the sag value is given by Equation 1 above.
b) When d1 ≤ d ≤ d2 The sag value is given by the following equation (4). Equation 4 is obtained by adding equation 2 and two equations that cancel it. In Equation 4, the first term is Equation 2 and represents the shape of a curved surface (a spherical surface if there is no aspherical coefficient) with a curvature Cf. The second term is a term that cancels the sag difference between the curved surface with the curvature Cf and the curved surface with the curvature Cc at the point d1. These are the same as in the first embodiment.
The third term is a term that cancels the difference in slope at the d1 point by calculating the differential value at the d1 point. Here, a small numerical value of 0.001 was used as a specific example because the difference in slope at the d1 point is extremely small.
c) When d>d2 The sag value is given by the following equation (5). When d>d2, the curve in the first region 13 is used. However, as described with reference to FIG. ] is subtracted to cancel the value in the Z-axis direction of the original curve R1.

In Embodiment 2, a different curve R2 can be connected without steps to the lens surface based on the curve R1. The difference from the first embodiment is that the curve R1 and the curve R2 are smoothly connected near the position d1, which is the inner boundary line of the region FE.

(Embodiment 3)
The third embodiment is a variation of the spectacle lens 11 of the first and second embodiments. Embodiments 1 and 2 are examples in which the second region 14 is uniformly inclined in all directions from the optical center. 14C) is changed according to the orientation.
FIG. 9 is an image diagram of the layout of the second area, in which the second area is expressed by gradation so that the absolute value of the curvature becomes darker as the value is farther from the absolute value of the curvature of the first area.
An azimuth angle is taken with the X-axis direction from the lens optical center as a starting point. In the figure, as an example, the horizontal direction at the time of wearing is assumed to be 0, and the azimuth angle is θ.
Let dC be the difference between the curvature Cc of the first region 13 (correction zone) and the curvature Cf of the second region 14 (FE zone), and let dC(Cc-Cf).
If the curvature at each azimuth angle is represented by C, the following equation (6) is obtained. That is, the formula 6 is a formula for changing the curvature Cf, which is the reference of the second region 14, according to an arbitrary azimuth angle θ. By applying this formula to Embodiment 1 or Embodiment 2, the depth of focus in the second region 14 can be changed according to the azimuth angle θ.
FIG. 9 shows that the three concentric second regions 14 of the lens have the greatest depth of focus in the downward direction, and the extension of the depth of focus in the upward direction of the lens is 0, i.e. the same depth of focus as the first region 13. It is an image diagram of becoming. In the third embodiment as well, it can be expected that the wearing comfort will be improved in the same manner as described above, and near vision will not occur in a state where the field of view has an extended depth of focus when the eyeglasses slip off.

(Embodiment 4)
Embodiment 4 is a variation of spectacle lens 11 of Embodiments 1 to 3. FIG. In Embodiments 1 to 3, the plurality of second regions 14 (rings 14A to 14C) are arranged concentrically with the first region 13 having a constant curvature interposed therebetween. 4 is an example in which the ring-shaped rings 14A to 14C are concentrically arranged adjacent to each other by shifting the directions of the curvatures to be changed in the rings 14A to 14C in the inner and outer rings 14A to 14C. The fourth embodiment is an example in which the first region 13 is not sandwiched between the rings 14A-14C. FIG. 10 is a layout image diagram of the second area expressed by gradation so that the absolute value of the curvature becomes darker as the value is farther from the absolute value of the curvature of the first area.
As in the third embodiment, the difference between the curvature Cc of the first region 13 (correction zone) and the curvature Cf of the rings 14A to 14C (FE zones) is dC, dC (Cc-Cf), and an arbitrary orientation Assuming an angle θ, the curvature C of the innermost ring 14A is, depending on the orientation,
C=Cf+dC*(cos θ) ² .
Similarly, the curvature C of ring 14B, depending on the orientation, is
C=Cf+dC*{1−(cos θ) ² }.
Similarly, the curvature C of the ring 14C, depending on the orientation, is
C=Cf+dC*(cos θ) ² .
Also in the fourth embodiment, it can be expected that the feeling of wearing is improved in the same manner as described above.

(Example 1)
Example 1 is an example corresponding to the first embodiment described above.
As shown in FIG. 11, the spectacle lens 11 of Embodiment 1 was manufactured with a viewing angle of 40 degrees, and a simulation was performed for viewing this.
The refractive power of the first region 13 of the manufactured spectacle lens 11 is -2.00D. The three rings 14A-14C interleaved with the correction zones produced a lens with an equivalent power of +2.5D positive relative to the correction zones. Curvature of lens surface = 0.00612,
The curvature of the first region 13=0.00947, and the curvature of the rings 14A to 14C=0.00281.
The distance (position) from the optical center of the second region 14 is as follows.
d<5 mm first region 13
d = 5 mm to 7 mm Ring 14A
d=7 mm to 9 mm first region 13
d = 9m to 11m Ring 14B
d=11 mm to 13 mm first region 13
d = 13 mm to 15 mm Ring 14C
d>15 mm first region 13
The result of simulating this spectacle lens 11 is shown in FIGS.
FIG. 12(a) is a graph of displacement (rotation of the eyeball) with respect to the turning point, where the vertical axis is the elevation angle up to 40 degrees from the horizontal direction, and the horizontal axis is the refractive power. FIG. 12A is a graphical representation of the three types of curves, where A is the refractive power in the circumferential direction, B is the refractive power in the radial direction, and C is the equivalent spherical power (=0.5*(A+B )), respectively. The curve basically shows the characteristics of the first region 13, and the part that is discontinued and shifted to the side shows the characteristics of the rings 14A to 14C.
From the graph in FIG. 12(a), the refractive power of the rings 14A to 14C changes gradually as the angle changes. I know it feels good.
FIG. 12(b) is a graph in which the vertical axis is the elevation angle up to 40 degrees from the horizontal direction, and the horizontal axis is the displacement based on the turning point, which is the prism power. The positive side of the prism is upward. In FIG. 12(b) as well, the curve basically shows the characteristics of the first region 13, and the discontinuous portion shows the characteristics of the rings 14A to 14C. The D curve is the change in prism between horizontal and 40 degrees elevation, and the E curve represents the amount of prism jump. From FIG. 12(b), it can be seen that the change in the prism power is moderate and the wearing feeling is good.

(Example 2)
Example 2 is an example corresponding to the second embodiment described above.
In Example 2, as in Example 1, spectacle lens 11 of Embodiment 1 was produced with a viewing angle of 40 degrees as shown in FIG. Various numerical conditions of the manufactured spectacle lens 11 are the same as those of the spectacle lens 11 of the first embodiment. The graphs of FIGS. 13(a) and 13(b) show simulation results of the second embodiment. From these results, the feeling of wearing is mild as in Example 1. Especially in Example 2, as shown in FIG. 13B, the difference in prism power is small at the boundary between the first region 13 and the rings 14A to 14C.

(Example 3)
Example 3 is an example corresponding to the above-described third embodiment.
The curvature Cc of the first region 13 (correction zone) was set to 0.00947, and the curvature Cf of the second region 14 (FE zone) was set to 0.00281. The spectacle lens 11 of Embodiment 3 was produced in the same manner as in Example 1 with respect to other numerical conditions, and a visual simulation was performed in the same manner as in Example 1. FIG.
Graphs of FIGS. 14(a) and 14(b) and graphs of FIGS. 15(a) and 15(b) show simulation results of the third embodiment. Graphs of FIGS. 14(a) and 14(b) show optical characteristics of refractive power and prism power in the upper half from the optical center of the lens, and graphs of FIGS. 15(a) and (b) show refractive power in the lower half from the optical center of the lens. Optical properties of power and prism power.
In the spectacle lens 11 of Example 3, the second region 14 (FE zone) above the lens does not have the effect of extending the depth of focus, and a view equivalent to that of a normal single-focal lens can be realized. It is also comfortable to wear.

(Example 4)
Example 4 is an example corresponding to the above-described fourth embodiment.
As in Example 3, the curvature Cc of the first region 13 (correction zone) was set to 0.00947, and the curvature Cf of the second region 14 (FE zone) was set to 0.00281. The spectacle lens 11 of Embodiment 3 was produced in the same manner as in Example 1 with respect to other numerical conditions, and a visual simulation was performed in the same manner as in Example 1. FIG.
The graphs of FIGS. 16(a) and 16(b) and the graphs of FIGS. Graphs of FIGS. 16(a) and 16(b) show optical characteristics of refractive power and prism power in the upper half from the optical center of the lens, and graphs of FIGS. 17(a) and (b) show refractive power in the lower half from the optical center of the lens. Optical properties of power and prism power.
In the spectacle lens 11 of Example 43, the second region 14 (FE zone) above the lens is cut in each direction, thereby cutting the distortion of the concentric space and improving the wearing feeling as compared with Example 1. .

(Comparative example)
A comparative example is a simulation of a case where a step occurs at the inner boundary line of the second region as shown in FIG.
The refractive power of the first region 13 of the manufactured spectacle lens 11 is -2.00D. The three rings 14A-14C interleaved with the correction zones produced a lens with an equivalent power of +2.5D positive relative to the correction zones. Curvature of lens surface = 0.00612,
The curvature of the first region 13=0.00947, and the curvature of the rings 14A to 14C=0.614.
The distance (position) from the optical center of the second region 14 is as follows.
d<5 mm first region 13
d = 5 mm to 7 mm Ring 14A
d=7 mm to 9 mm first region 13
d = 9m to 11m Ring 14B
d=11 mm to 13 mm first region 13
d = 13 mm to 15 mm Ring 14C
d>15 mm first region 13
A visual simulation was performed in the same manner as in Examples 1-4.
The graphs of FIGS. 18(a) and 18(b) show simulation results of the comparative example. In the spectacle lens 11 of the comparative example, the rings 14A to 14C exhibit a positive refractive power, but due to the large difference in prism power between the rings 14A to 14C at the boundary with the first region 13, the spectacle lens 11 is notable as a spectacle lens. The lens is uncomfortable to wear

The above embodiments are merely described as specific embodiments to illustrate the principles and concepts of the present invention. That is, the present invention is not limited to the above embodiments. The present invention can also be embodied, for example, in the following modified aspects.
- The number, width, etc. of the ring-shaped second regions 14 in the above-described embodiment are examples, and may be implemented in other forms. The same applies to the examples, and the numerical values can be changed as appropriate.
- In Embodiment 2, for example, the curve R1 connected to d2 may be inclined so as to be smoothly connected to the curve R2 forming the second region .
In the first to fourth embodiments, the case where the depth of focus is on the plus side has been described, but the case where the depth of focus is on the minus side can also be designed based on the same design concept. In addition, although the corrected refractive power is a minus lens in the above description, it may be a plus lens.
・In the fourth embodiment, instead of arranging the first regions 13 and the second regions 14 alternately, the three rings 14A to 14C, which are the second regions 14, are curved in the circumferential direction, that is, according to the phase. I was trying to change the The adjacent ring-shaped second regions 14 are arranged such that the curvatures thereof are shifted. When there are three or more ring-shaped second regions 14, this arrangement
1st, 3rd, 5th, 7th, . . . positions C=Cf+dC*(cos θ) ²
2nd, 4th, 6th, . . . positions C=Cf+dC*{1−(cos θ) ² }
It can be generalized by Although the phase is shifted by 180 degrees here, the phase may be shifted by another angle.

The present invention is not limited to the configurations described in the above embodiments. The constituent elements of each embodiment and modifications may be arbitrarily selected and combined. Arbitrary constituent elements of each embodiment and modifications, arbitrary constituent elements described in Means for Solving the Invention, or configurations embodying arbitrary constituent elements described in Means for Solving the Invention Elements may be combined arbitrarily. We intend to acquire the rights for these as well in the amendment of the present application or in a divisional application.
In addition, the applicant intends to acquire rights to the entire design or partial design by converting the design application. Although the entire device is drawn in solid lines in the drawing, the drawing includes not only the overall design but also the partial design claimed for a part of the device. For example, it is a drawing that includes a part of the device as a partial design regardless of the member, as well as a partial design of a part of the member of the device. A part of the device may be a part of the device, or may be a part of the member.

Reference numerals 11: spectacle lens, 13: first region, 14A to 14C: second region.

Claims (19)

Spectacles provided with a first region having a predetermined refractive power for refractive correction and a second region having a refractive power different from the first region on either the front surface or the rear surface of the lens is a lens,
A spectacle lens according to claim 1, wherein said second region is formed in a ring-shaped aspherical shape, and said second region has an extended depth of focus due to astigmatism. 2. The spectacle lens according to claim 1, wherein the ring-shaped second region is formed in a strip shape of equal width.
3. The spectacle lens according to claim 2, wherein the ring-shaped second region has a width of 0.8 mm or more and 3.0 mm or less.
The spectacle lens according to any one of claims 1 to 3, wherein the ring-shaped second region is arranged outside a circular region with a radius of 3 mm around the center of the lens. The spectacle lens according to any one of claims 1 to 4, wherein a plurality of said ring-shaped second regions are concentrically arranged at intervals.
6. The spectacle lens according to claim 5, wherein widths of the plurality of ring-shaped second regions are not the same.
7. The spectacle lens according to claim 5, wherein the intervals between a plurality of adjacent ring-shaped second regions are not the same.
The spectacle lens according to any one of claims 5 to 7, wherein the curvatures of the adjacent ring-shaped second regions are not the same. The spectacle lens according to any one of claims 1 to 8, wherein the center position of the ring-shaped second region coincides with the optical center of the lens. The spectacle lens according to any one of claims 1 to 9, wherein the first region has an aspheric shape. The spectacle lens according to any one of Claims 1 to 10, wherein the second region has astigmatism of 0.5D or more as an absolute value with respect to the first region. 12. The ring-shaped second region according to any one of claims 1 to 11, wherein the curvature in a cross-sectional direction passing through the center position of the ring has a portion whose curvature changes depending on the phase in the circumferential direction of the ring shape. eyeglass lenses. 14. The spectacle lens according to any one of claims 1 to 13, wherein the ring-shaped second region is connected to the first region adjacent thereto in a cross-sectional direction passing through the center position of the ring without steps. In the cross-sectional direction passing through the center position of the ring, the ring-shaped second region has a slope equal to that of the first region at least at an inner boundary position where the second region is connected to the first region. The spectacle lens according to claim 13, characterized in that: In the ring-shaped second region, in the cross-sectional direction passing through the ring center position, the slope at the outer boundary position where the second region is connected to the first region is the same as the slope of the first region. 15. The spectacle lens according to claim 14, characterized in that The spectacle lens according to any one of claims 1 to 12, wherein the second region is provided on the rear surface of the lens. The spectacle lens according to any one of Claims 1 to 13, wherein the first region is provided on the rear surface of the lens. A spectacle lens according to any one of claims 1 to 17, which is a lens for suppressing progression of myopia. A spectacle lens according to any one of claims 1 to 17, which is a hyperopia progression suppressing lens.

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