JP2016026324A - Lens for spectacle, spectacle, design method of spectacle lens, and design device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a spectacle lens having good wearing feeling and high fashionability.SOLUTION: A spectacle lens includes a stylish zone 16 that is included in at least part of a range from 20 degrees to 60 degrees of the rotation angle of the eye ball of a wearer and in which correction of astigmatism takes preference over correction of average refractive power based on a degree of prescription and a comfort zone 15 that is a region inside of the stylish zone 16 and in which correction of average refractive power takes preference over correction of astigmatism. The stylish zone 16 includes points such that an astigmatism value has a minus extreme value and an astigmatism value has a plus extreme value.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a spectacle lens, spectacles, a spectacle lens design method, and a design apparatus.

  At least two elements of correcting the average refractive power with respect to the prescription power, that is, reducing the average refractive power error and reducing astigmatism, design the spectacle lens so that a clear field of view is obtained. It was an indispensable element. For example, Patent Document 1 describes that a spectacle lens that can suppress not only the average refractive power error and astigmatism but also distortion can be provided while using a shallow base curve. In the spectacle lens of Patent Document 1, the outer surface is a spherical surface, the inner surface is a rotationally symmetric aspheric surface, and aberration is focused on the average refractive power error and astigmatism at the central portion where the viewing angle ranges from 0 to 30 °. Correction is performed, and the aberration is corrected with emphasis on distortion at the periphery. As a result, a clear image is obtained in the range covered by the eye movement during wearing, and an image with small distortion is formed in the peripheral portion of the retina, so that a good field of view can be obtained for the wearer. With such aberration correction weighting, it is possible to maintain the sensible optical performance during wearing without having to correct all of the average refractive power error, astigmatism, and distortion aberration throughout the entire lens. It has been described that it is possible to achieve both excellent optical performance and the adoption of a shallow base curve for thinning.

JP 2003-215507 A

  However, although the spectacle lens described in Patent Document 1 can obtain a clear image at the center of the lens, there is a risk that the image at the periphery is distorted or unclear because the astigmatism at the periphery is not sufficient. It was. Such distortion of the peripheral image may cause a decrease in fashionability, such as a decrease in wearing feeling and a contour of the wearer (person wearing glasses) appearing to be distorted.

  Glasses are not only an important medical tool to supplement vision but also an important fashion item that affects an individual's impression. Accordingly, there is a demand for eyeglasses and eyeglass lenses that are easier to use and more fashionable.

  One aspect of the present invention is included in at least a part of the rotation angle of the wearer's eyeball from 20 degrees to 60 degrees, and correction of astigmatism has priority over correction of average refractive power based on prescription power. In addition, the eyeglass lens includes a first region and a second region formed inside the first region and prioritizing correction of the average refractive power over correction of astigmatism.

  The spectacle lens of this aspect allows a certain amount of error in the average refractive power in a region included in at least a part of the rotation angle range of 20 degrees to 60 degrees, and instead corrects astigmatism favorably. Includes a first region. If priority is given to correction of the average refractive power in a region where the rotation angle is large, astigmatism will increase if the rotation angle increases even if correction of astigmatism is attempted. For this reason, it is difficult to obtain a clear image when looking far away in a region where the rotation angle is large. However, if a certain amount of error in the average refractive power is allowed in a region where the rotation angle is large, astigmatism can be easily corrected, and astigmatism can be made zero or near zero. A clear and less distorted image can be obtained. In addition, by allowing a certain amount of error in the average refractive power in a region where the rotation angle is large, options for the shape of the outer surface (base curve) and / or the shape of the inner surface of the spectacle lens increase. Therefore, it is possible to provide a spectacle lens that is easier to use and more fashionable.

  The first region preferably includes a point where an astigmatism value (astigmatism) takes a negative extreme value and a point where a positive extreme value takes. By changing the astigmatism to have extreme values on the minus side and the plus side in the first region, the astigmatism in the first region vibrates around 0 in a large rotation angle range. Astigmatism does not diverge greatly from zero.

  Further, in the first region, the radial power value (radial power) and the circumferential power value (circumferential power) approach each other and approach each other in the direction in which the rotation angle increases. It is desirable to include a changing region. Astigmatism can be brought close to zero by bringing the radial power and the circumferential power close to each other. Therefore, it is possible to provide a spectacle lens in which the astigmatism of the first region having a large rotation angle vibrates around 0, and a clearer image can be obtained within a large rotation angle range.

  Furthermore, it is desirable that the maximum error of the average refractive power with respect to the prescription power in the first region is 30% or less. Thereby, since it is possible to suppress an error in the average refractive power from becoming too large, it is possible to provide a spectacle lens capable of obtaining a clearer image in the first region having a large rotation angle.

  The second region where the correction of the average refractive power is prioritized over the correction of astigmatism changes so that the radial power value and the circumferential power value are separated from each other in the direction in which the rotation angle increases. It is desirable to include the area to be. Since the average refractive power is an average of the radial power and the circumferential power, fluctuations in the average refractive power in the second region at the center of the spectacle lens can be suppressed. Therefore, a spectacle lens in which the correction of the average refractive power is prioritized over the correction of astigmatism, the average refractive power error is small, and the average refractive power that matches the prescription power or is close to the prescription power is provided in the central portion. Can be provided.

  In this spectacle lens, when the prescription power is negative, it is desirable that the design diameter of the second region is smaller as the absolute value of the prescription power is larger. When the prescription power is negative, the rotation angle is smaller than the viewing angle, so that a sufficient viewing angle can be obtained even if the second area is reduced. In general, the spectacle lens tends to be thicker as the prescription power becomes negative. Accordingly, when the absolute value of the prescription power is large, by securing a wide first region in which astigmatism is suppressed, the spectacle lens is more easily fashionable without impairing the ease of use as a spectacle lens. A lens can be provided.

  When this spectacle lens prescription includes astigmatism correction with a minus power, the design shape of the second region is preferably an ellipse. The prescription for astigmatism correction varies depending on the astigmatism axis. For this reason, since the rotation angle differs depending on the astigmatism axis with respect to the viewing angle, the first region can be further widened by making the design shape of the second region an ellipse. Therefore, it is possible to provide a spectacle lens with higher fashionability without impairing the ease of use as a spectacle lens including astigmatism correction.

  One of the other aspects of the present invention is included in at least a part of the rotation angle of the wearer's eyeball from 20 degrees to 60 degrees, and is more astigmatic than the correction of the average refractive power based on the prescription power. A spectacle lens having: a first region where aberration correction is prioritized; and a second region which is formed inside the first region and prioritizes correction of average refractive power over correction of astigmatism A spectacle frame to which the spectacle lens is attached. By adopting this spectacle lens for spectacles, it is possible to provide spectacles that are easier to use and more fashionable than before.

  One of the other different aspects of the present invention is included in the range of 20 degrees to 60 degrees of the rotation angle of the eyeball of the wearer, and correction of astigmatism takes priority over correction of average refractive power based on prescription power. An eyeglass lens comprising: a first region formed within the first region; and a second region where the correction of the average refractive power is prioritized over the correction of astigmatism inside the first region. It is a design method. As a result, it is possible to design and provide a spectacle lens that can provide a clear image in the first region with a large rotation angle, is easy to use, and has high fashionability.

  Providing the second region of the spectacle lens design method may include reducing the design diameter of the second region as the absolute value of the prescription power is larger when the prescription power is negative. desirable. In addition, providing the second region preferably includes making the design shape of the second region an ellipse when the spectacle lens prescription includes astigmatism correction with a minus power.

  One of further different aspects of the present invention is a spectacle lens design apparatus. This device (design device) is included in at least a part of a unit (functional unit, means) for acquiring spectacles specifications including prescription power and a rotation angle of the wearer's eyeball from 20 degrees to 60 degrees, A first unit for designing a first region in which correction of astigmatism is prioritized over correction of average refractive power based on prescription power (first region design unit, first functional unit, first means) And a second unit (second region design unit, second region) that is located inside the first region and that designs the second region in which the correction of the average refractive power is prioritized over the correction of astigmatism. Functional unit, second means). This makes it possible to design a spectacle lens that is easy to use for the wearer (user) and that is more fashionable.

  When the prescription frequency is negative, the second unit reduces the design diameter of the second region as the absolute value of the prescription frequency increases, and when the prescription frequency is positive, It is desirable to include a unit that makes the design diameter of the two regions constant.

  The apparatus preferably further comprises an evaluation unit that evaluates when and when viewed with the designed spectacle lens. By evaluating the state of use and the state when viewed, it is possible to design a spectacle lens that is more fashionable and easy for the wearer to wear.

FIG. 1A is a diagram showing a state of wearing the glasses of the example, and FIG. 1B is a diagram showing a state of wearing the glasses of a comparative example. The figure explaining distortion aberration when wearing glasses. The figure explaining distortion aberration when it wears spectacles and is seen. The figure which shows the matter considered in the design which attaches importance to a feeling of wear or an external appearance. The figure which shows the outline | summary of the spectacle lens of an Example. 6A is a diagram illustrating characteristics including the power error and astigmatism of the lens of Example 1, and FIG. 6B is a diagram illustrating characteristics including the power error and astigmatism of the lens of Comparative Example 1. FIG. 6C shows distortion. FIG. 7A is a diagram showing a state in which the shape of the outer surface of the lens of Example 1 is changed with respect to the lens of Comparative Example 1, and FIG. 7B is the inner surface of the lens of Example 1 with respect to the lens of Comparative Example 1. The figure which shows a mode that the shape of was changed. The flowchart which shows the general | schematic process of designing and manufacturing a spectacle lens. The figure which shows the motion of the eyeball with respect to the motion of a head. FIG. 10A illustrates a viewing angle when viewed through a minus lens, and FIG. 10B illustrates a viewing angle when viewed through a plus lens. The figure which shows the relationship of rotation angle (beta) with respect to frequency according to viewing angle (alpha). The figure which shows an example of the function which sets the rotation angle of a comfort zone based on prescription frequency. FIG. 13A is a diagram showing characteristics including power error and astigmatism of the lens of Example 2, and FIG. 13B is a diagram showing characteristics including power error and astigmatism of the lens of Comparative Example 2. FIG. 13C shows distortion. FIG. 14A is a diagram showing a state in which the shape of the outer surface of the lens of Example 2 is changed with respect to the lens of Comparative Example 2, and FIG. 14B is the inner surface of the lens of Example 2 with respect to the lens of Comparative Example 2. The figure which shows a mode that the shape of was changed. FIG. 15A is a diagram illustrating characteristics including the power error and astigmatism of the lens in the 90 degree direction of Example 3, and FIG. 15B is the power error and astigmatism of the lens in the 180 degree direction of Example 3. The figure which shows the characteristic containing an aberration. The figure which shows an elliptical comfort zone. 17A is a diagram showing characteristics including the power error and astigmatism of the lens in the 90 ° direction of Comparative Example 3, and FIG. 17B is the power error and astigmatism of the lens in the 180 ° direction of Comparative Example 3. The figure which shows the characteristic containing an aberration. FIG. 18A shows a distortion aberration in the 90-degree direction, and FIG. 18B shows a distortion aberration in the 180-degree direction. FIG. 19A is a diagram showing characteristics including power error and astigmatism of the lens of Example 4, and FIG. 19B is a diagram showing characteristics including power error and astigmatism of the lens of Comparative Example 4. FIG. 19C shows distortion aberration. FIG. 20A is a diagram illustrating characteristics including power error and astigmatism of the lens of Example 5, and FIG. 20B is a diagram illustrating characteristics including power error and astigmatism of the lens of Comparative Example 5. FIG. 20C shows distortion. FIG. 21A is a diagram illustrating characteristics including the power error and astigmatism of the lens of Example 6, and FIG. 21B is a diagram illustrating characteristics including the power error and astigmatism of the lens of Comparative Example 6. FIG. 21C shows distortion aberration. 22A is a diagram showing characteristics including power error and astigmatism of the lens of Example 7, and FIG. 22B is a diagram showing characteristics including power error and astigmatism of the lens of Comparative Example 7. 22 (c) is a diagram showing distortion. FIG. 23A is a diagram illustrating characteristics including power error and astigmatism of the lens of Example 8, and FIG. 23B is a diagram illustrating characteristics including power error and astigmatism of the lens of Comparative Example 8. FIG. 23C shows distortion. FIG. 24A is a diagram illustrating characteristics including power error and astigmatism of the lens of Example 9, and FIG. 24B is a diagram illustrating characteristics including power error and astigmatism of the lens of Comparative Example 9. FIG. 24C shows distortion aberration. Block diagram showing the main configuration of the design equipment.

  FIG. 1 shows a user (wearer) wearing spectacles. FIG. 1A shows a user 2 wearing spectacles 1 in which the spectacle lens 10 of the embodiment of the present invention is attached to a frame (spectacle frame) 5, and FIG. 1B shows a spectacle lens 19 of a comparative example. A state in which a user 2 wears spectacles 9 in which a (general single focus lens) is attached to the same frame 5 is shown. In the spectacles 9 shown in FIG. 1B, a part 2 a of the contour of the face of the user 2 seen through the peripheral part of the spectacle lens 19 is largely shifted from the other part 2 b due to the aberration of the peripheral part of the spectacle lens 19. Yes. On the other hand, in the spectacles 1 shown in FIG. 1A, a part 2a of the contour of the face of the user 2 seen through the peripheral part of the spectacle lens 10 is hardly displaced from the other part 2b. Therefore, the spectacles 1 are stylish spectacles with little discomfort when the wearer 2 is viewed through the spectacle lens 10 (discomfort when other people see the wearer 2).

  As described above, glasses (glasses) are not only an important medical tool for supplementing eyesight, but also an important fashion item that affects the impression of individual users. In other words, eyeglasses are required to have an appropriate frequency and easy-to-use design for medical use, are as thin as possible as a fashion item, have a good “look” (when they are passed through the lens), and are also user-friendly. It is desired that the eyeglasses are finished according to the image. Therefore, glasses having a stylish appearance as well as a comfortable wearing feeling are demanded for recent glasses.

  FIG. 2 shows how the distortion aberration changes with the base curve when viewed with glasses. FIG. 3 shows a state in which the distortion aberration changes with the base curve when viewed with glasses. 2 and 3 show the distortion viewed through the single focus lens 19 of the comparative example having a prescription power SPH of −4.0 (diopter, hereinafter “D”). The distortion shown in FIG. 2 is a state in which a lattice pattern is seen through the lens 19 from the inner surface 12 side of the single focus lens 19 as shown in FIG. 2A, and from FIG. As shown in FIG. 2, when the base curve (surface refractive power of the outer surface 11) becomes deeper, the distortion becomes small as shown in FIGS. 2 (f) to 2 (i), and the lens is easy to see when applied and has a little uncomfortable feeling.

  The distortion shown in FIG. 3 is a state in which a lattice pattern is seen through the lens 19 from the outer surface 11 side of the single focus lens 19 as shown in FIG. 3A, and from FIG. As shown in FIG. 3, when the base curve (surface refractive power of the outer surface 11) becomes deeper, the distortion increases as shown in FIGS. Therefore, a shallower base curve results in a lens with less discomfort when viewed with glasses. In this way, the evaluation when the wearer 2 sees wearing glasses is different from the evaluation when the wearer 2 wearing glasses sees.

  FIG. 4 collectively shows the evaluation when viewed with glasses and the evaluation when viewed with glasses. When the design for emphasis is placed on the wearing feeling, the obtained eyeglass lens is less distorted when viewed, but the base curve is deeper, the lens is thicker, and the distorted when viewed is larger. On the other hand, when an appearance-oriented design is used, the obtained spectacle lens has a shallow base curve, a thin lens, and a small distortion when viewed, but a large distortion when viewed. Therefore, it is difficult to design a conventional spectacle lens having both a feeling of wearing and an appearance (easy to use, high fashion, refreshing wearing feeling and stylish appearance).

  FIG. 5 shows a spectacle lens 10 of the embodiment. This spectacle lens 10 is a spectacle lens that achieves both a refreshing wearing feeling and a stylish appearance, and includes a circular comfort zone (second region) 15 centered on a fitting point FP at the center and the outside thereof. And a stylish zone (first region) 16. This spectacle lens 10 provides a comfortable wearing feeling in the central comfort zone 15 and can provide a stylish appearance in the outer stylish zone 16, and is a high-quality spectacle lens when viewed and seen. It has become. In FIG. 5, the boundary 17 between the comfort zone 15 and the stylish zone 16 is indicated by a curved line as a virtual area for the sake of explanation, but the boundary 17 is an area where a line can actually be seen or a shadow can be seen. is not. The comfort zone 15 and the stylish zone 16 may be adjacent to each other, and a zone for other functions may exist between the comfort zone 15 and the stylish zone 16. The same applies to the following.

  The comfort zone 15 is a zone designed for a comfortable view, and secures a clear and clear view at the center of the lens 10. Therefore, in the comfort zone 15, the average refractive power AvP is designed (corrected and adjusted) so that the error (average refractive power error, power error) with respect to the prescription power SPH is small, and the value of astigmatism AS is also small. It has been corrected.

  The stylish zone 16 is a zone that employs a design that suppresses thickness and scum at the periphery of the lens, and ensures a stylish appearance. Furthermore, in the eyeglass lens 10, the stylish zone 16 is designed not only to have a sense of incongruity when viewed, but also to reduce a sense of discomfort when viewed. That is, when the comfort zone 15 and the stylish zone 16 in the spectacle lens 10 are compared, the stylish zone (first region) 16 is a region in which the rotation angle β of the wearer's eyeball is included in the range of 20 degrees to 60 degrees. The correction of the astigmatism AS in the distance vision is prioritized over the correction of the average refractive power AvP with respect to the prescription power SPH, and the comfort zone (second region) 15 is located inside the stylish zone 16. In which the correction of the average refractive power AvP is prioritized over the correction of the astigmatism AS.

  That is, the stylish zone 16 of the spectacle lens 10 accepts a certain amount of power error in comparison with the comfort zone 15, while correcting the astigmatism AS in preference to the occurrence of the power error, and the astigmatism AS. Is vibrated or converged in the vicinity of 0. Therefore, in the stylish zone 16, even if the sharpness of the image is lowered due to the inability to secure the prescription power SPH, the blur of the image due to the deterioration of the astigmatism AS can be suppressed and the power error can be accepted. We try to get a clear image as much as possible. In addition, by improving the astigmatism AS, image distortion and generation of distortion can be suppressed. Therefore, the stylish zone 16 of the spectacle lens 10 is designed so that a sufficiently clear image can be obtained as a peripheral portion of the spectacle lens 10 in addition to a stylish appearance.

  Also, for example, as shown in FIG. 2 (f), when the entire spectacle lens 19 is designed so that the power error is reduced, the aberration becomes too large in the peripheral portion where the rotation angle β is large, and a clear image is obtained. It becomes a state when it is hard to be done. On the other hand, in the eyeglass lens 10, the appearance of the peripheral portion can be typically improved as shown in FIG. 2 (i) by reducing the astigmatism AS in the peripheral portion. Therefore, the stylish zone 16 of the spectacle lens 10 can be improved in appearance and provide a stylish appearance, and can be improved in appearance by correcting the astigmatism AS in the peripheral portion well.

(Example 1 and Comparative Example 1)
In FIG. 6A, the error (power error) PE of the average refractive power AvP with respect to the prescription power SPH of the eyeglass lens 10 of Example 1 is indicated by a two-dot chain line, and the astigmatism AS for far vision is indicated by a broken line. Astigmatism AS in far vision is astigmatism when viewed at infinity. The power error PE and astigmatism AS show the result of simulating the power error PE and astigmatism AS in a state where both the surfaces (inner surface and outer surface) 12 and 11 are transmitted when the spectacle lens 10 is viewed. . The eyeglass lens 10 of Example 1 is a single focus lens having an object-side surface (outer surface) 11 and an eyeball-side surface (inner surface) 12 that are rotationally symmetric aspheric surfaces, and corrects myopia with a prescription power SPH of −10.0D. It is a spectacle lens to do. The power error PE is a ratio (%) of the difference between the prescription power SPH and the average refractive power AvP to the prescription power SPH. For example, since the refractive power of the eyeglass lens 10 of this example is −10.0D, if the average refractive power AvP becomes −9.0D, the power error PE is + 1.0D when expressed as a difference, and when expressed as a ratio. 10%. Specific lens data is as follows.
Vertex power [D]: -10.00
External paraxial curvature (0) [D]: 0.50
External paraxial curvature (10) [D]: 0.49
External paraxial curvature (20) [D]: 0.41
External paraxial curvature (30) [D]: 0.25
Inner paraxial curvature (0) [D]: 10.50
Inner paraxial curvature (10) [D]: 10.12
Inner paraxial curvature (20) [D]: 8.16
Inner paraxial curvature (30) [D]: 6.14
Center thickness [mm]: 1.10

  Further, in FIG. 6A, the error ME of the radial power MD with respect to the prescription power SPH is indicated by a solid line, and the error SE of the circumferential power SD with respect to the prescription power SPH is indicated by a one-dot chain line. The radial power MD is the meridional cross-sectional power, the circumferential power SD is the sagittal cross-sectional power, and the average power (average refractive power) AvP is the average of the radial power MD and the circumferential power SD. The astigmatism AS is the difference between the radial power MD and the circumferential power SD, and in this figure, is the difference between the radial power error ME and the circumferential power error SE.

  As shown in FIG. 6A, the spectacle lens 10 of this example is a region in which the rotation angle β of the eyeball is included in the range of 20 degrees to 60 degrees, specifically, the rotation angle β is larger than about 23 degrees. In the region, when the rotation angle β increases, the value of astigmatism AS has an extreme value (as (−)) on the minus side, passes 0 (as (0)), and then an extreme value (as (0)) on the plus side. as (+)). Further, along the direction in which the rotation angle β increases in this region, the radial power error ME and the circumferential power error SE change so as to approach each other after approaching and intersecting each other. That is, in this region, the radial power MD and the circumferential power SD change so as to approach each other after approaching and intersecting each other in the direction in which the rotation angle β increases. Therefore, in this region, the power error PE is about 14% at a rotation angle β of 50 degrees with respect to the prescription power SPH (−10.0 D), but the astigmatism AS converges around 0 instead. It has been corrected to do. In addition, in the spectacle lens with the prescription power SPH of -10.0D, the total rotation occurs when viewed from the inside when the rotation angle β is around 50 degrees, and thus the rotation angle beyond that is not evaluated. Also in the following examples and comparative examples, the state beyond the rotation angle at which total reflection occurs is not evaluated although it depends on the value of the prescription power SPH.

  On the other hand, in the region where the rotation angle β is smaller than about 23 degrees, the sign of the radial power error ME and the circumferential power error SE is different (in this example, ME is negative and SE is positive), and rotation is performed. The angles β change so as to be separated from each other in the increasing direction. That is, the radial power MD and the circumferential power SD change so as to be separated from each other in the direction in which the rotation angle β increases. In this region, the power error PE is almost 0 and the astigmatism AS is also corrected well, but the astigmatism AS increases as the rotation angle β increases.

  As described above, the spectacle lens 10 has astigmatism AS for far vision with respect to the correction of the average refractive power (power error PE) with respect to the prescription power SPH with the boundary 17 near the rotation angle β of about 23 degrees. The first region (stylish zone) 16 in which the correction of the lens is prioritized is corrected, and the inner portion, that is, the central portion of the spectacle lens 10 inside the boundary 17 is corrected for the average refractive power (power) with respect to the correction of the astigmatism AS. The error PE) is a second area (comfort zone) 15 in which priority is given.

In FIG. 6B, the error (power error) PE of the average refractive power AvP with respect to the prescription power SPH of the spectacle lens 19 of Comparative Example 1 is indicated by a two-dot chain line, and the astigmatism AS in the distance vision is indicated by a broken line, and the radial direction The frequency error ME is indicated by a solid line, and the circumferential frequency error SE is indicated by a one-dot chain line. The eyeglass lens 19 of Comparative Example 1 is a single focus lens having an object-side surface (outer surface) 11 and an eyeball-side surface (inner surface) 12 that are rotationally symmetric aspheric surfaces, and corrects myopia with a prescription power SPH of −10.0D. It is a spectacle lens to do. Specific lens data is as follows.
Vertex power [D]: -10.00
External paraxial curvature (0) [D]: 0.50
External paraxial curvature (10) [D]: 0.49
External paraxial curvature (20) [D]: 0.41
External paraxial curvature (30) [D]: 0.25
Inner paraxial curvature (0) [D]: 10.50
Inner paraxial curvature (10) [D]: 10.20
Inner paraxial curvature (20) [D]: 9.23
Inner paraxial curvature (30) [D]: 8.63
Center thickness [mm]: 1.10

  In the spectacle lens 19 of Comparative Example 1, the rotation angle β is in the range of 0 to 50 degrees, and the radial power error ME and the circumferential power error SE are separated from each other in the direction in which the rotation angle β increases. It has changed. As a result, the power error PE is almost zero throughout the spectacle lens 19, and the astigmatism AS increases as the rotation angle β increases. Therefore, it can be said that the entire spectacle lens 19 is a comfort zone in which the correction of the average refractive power (power error PE) is prioritized over the correction of the astigmatism AS.

  In FIG. 6C, the distortion aberration of the eyeglass lens 10 of Example 1 is indicated by a solid line, and the distortion aberration of the eyeglass lens 19 of Comparative Example 1 is indicated by a broken line. It can be seen that distortion is improved in the peripheral portion of the lens, that is, in the stylish zone 16 of the eyeglass lens 10 of Example 1.

  As described above, when the spectacle lens 10 of Example 1 and the spectacle lens 19 of Comparative Example 1 are compared, the characteristics of the comfort zone 15 in the central portion are hardly changed, and the power error PE and astigmatism AS are excellent. It can be seen that the image is corrected and a clear image can be obtained. On the other hand, in the stylish zone 16 at the periphery of the eyeglass lens 10 of Example 1, astigmatism AS contains 0 and vibrates in the vicinity of 0 instead of accepting a power error PE of about 15% at the maximum. Astigmatism is improved as compared with the eyeglass lens of Comparative Example 1. Therefore, in the stylish zone 16, the astigmatism AS is greatly improved in addition to a reduction of the visual acuity correction ability by several ten percent, and in addition, the distortion is also improved.

  In addition, as shown in FIG. 7, in the stylish zone 16 of the spectacle lens 10, a certain amount of power error PE is allowed, so the options of the base curve 11 and the inner curve 12 are expanded. For example, as shown in FIG. 7A, the base curve 11 (solid line) of the eyeglass lens 10 of Example 1 is larger (curvature) at the periphery than the base curve 11 (dashed line) of the eyeglass lens 19 of Comparative Example 1. Radius can be reduced). Further, as shown in FIG. 7B, the curve 12 (solid line) on the inner surface of the spectacle lens 10 of Example 1 is set to the peripheral portion of the lens with respect to the curve 12 (broken line) on the inner surface of the spectacle lens 19 of Comparative Example 1. To make it smaller (increase the radius of curvature). In either case, the spectacle lens 10 can be made thinner and lighter than the spectacle lens 19. Therefore, also in this respect, the eyeglass lens 10 of Example 1 is suitable for users (wearers and wearers) who place importance on the appearance.

  As described above, the spectacle lens 10 of Example 1 has improved performance when viewed with respect to the spectacle lens 19 of Comparative Example 1, and further improved performance when viewed with it. Therefore, it is possible to provide a spectacle lens that is easy for the user to use, has a good wearing feeling, and has high fashionability.

  FIG. 8 is a flowchart showing a method for designing and manufacturing the eyeglass lens 10 of this example. The method described below can also be applied to Examples 2 to 9 described later. In step 21, spectacle specifications of the user (wearer, wearer) are acquired. The spectacle specification includes information such as the prescription power SPH, the necessity of astigmatism correction, and the astigmatism power (C) and the astigmatism axis (Ax) when astigmatism correction is required. Next, in step 22, a design diameter of the comfort zone (second region) 15 is set. The design diameter of the comfort zone 15 is hereinafter expressed by the rotation angle β.

  In step 22, if the prescription frequency SPH is negative (YES in step 23) in step 23, the designed diameter of the comfort zone 15 is determined based on the prescription frequency SPH in step 24, and the prescription frequency SPH is If it is positive (NO in step 23), the design diameter of the comfort zone 15 is set to a predetermined constant value in step 25 regardless of the prescription power SPH. In this example, in step 24, the design diameter of the comfort zone 15, that is, the rotation angle β is set smaller as the absolute value of the prescription power SPH is larger (that is, as the prescription power SPH is smaller). In step 25, the design diameter of the comfort zone 15, that is, the rotation angle β is set to 30 degrees.

  FIG. 9 shows an example of observing the head position (eye position) movement during the target search. The graph shown in FIG. 9 shows how much the head turns to recognize a target (object) that has moved by a certain angle in the horizontal direction from the gazing point (presented at a position separated by a predetermined distance). It shows. In a gaze state where attention is paid to the visual target (object), the head rotates in the direction of the object as indicated by a broken line 41. On the other hand, in a discriminating state where the target (object) is simply recognized, the movement of the head is about 10 degrees smaller than the angle (movement) of the object, as indicated by the dotted line 42. (Less). Based on this observation result, the limit of the range in which the object can be recognized by the movement of the eyeball can be set to about 10 degrees. Therefore, it is considered that the viewing angle α when the human sees the object by the movement of the eyeball while moving the head in a natural state is about 10 degrees at the maximum. For this reason, it is desirable that the region where a clear image is obtained when wearing spectacles, that is, the comfort zone 15 of the spectacle lens 10 is 10 degrees or more in view angle α.

  On the other hand, a range that can be watched only by eye movement is called a gaze field and has a viewing angle radius of about 50 degrees. However, when a person actually looks outside the front of the body, eye movements, head movements, and body movements are performed jointly, and the eye movements are in the range of a viewing angle radius (viewing angle α) of about 30 degrees. Stay on. In addition, although the resolving power is low in the peripheral portion of the retina, spatial information is accepted in the range of about 50 degrees in the viewing angle radius (viewing angle α), and image distortion is perceived. Therefore, it is sufficient that the comfort zone 15 can secure a range of about 30 degrees in view angle α, but it is also desirable that appropriate spatial information can be input to the eyeball through the stylish zone 16 located outside.

  FIG. 10 shows the relationship between the viewing angle α of the naked eye and the viewing angle α ′ when viewed through a spectacle lens. FIG. 10A shows a state viewed through the lens L1 having a negative power, and FIG. 10B shows a state viewed through the lens L2 having a positive power. When the lens power is negative, the viewing angle α ′ when viewed through the spectacle lens L1 is smaller than the viewing angle α of the naked eye, and when the lens power is positive, the viewing angle α ′ when viewed through the spectacle lens L2 is It becomes larger than the viewing angle α of the naked eye. Therefore, the angle (rotation angle) β at which the eyeball rotates to obtain a field of view equivalent to the naked eye viewing angle α (hereinafter referred to as viewing angle α) through the spectacle lens is the viewing angle α ′. The relationship between the viewing angle α ′ when viewed through the spectacle lens and the viewing angle α of the naked eye is the relationship between the sum A of the eyeball rotation distance and the spectacle wearing distance, the power of the spectacle lens, the thickness of the spectacle lens, and the like. It depends on.

  FIG. 11 shows the relationship between the power obtained under standard conditions and the rotation angle β for each viewing angle α of the spectacle lens. For example, the rotation angle β in the case of securing 30 degrees as the viewing angle α when viewed through a spectacle lens with a power of −10.0D is about 23 degrees, and when viewed through a spectacle lens with a power of 0.0D The rotation angle β when securing a viewing angle of 30 degrees is 30 degrees, and the rotation angle β when securing a viewing angle of 30 degrees when viewed through a spectacle lens with a power of 5.0D is about 37 degrees. Accordingly, the design diameter of the comfort zone 15 when designing the comfort zone 15 so as to ensure a viewing angle of 30 degrees can be changed by the prescription power SPH. In particular, when the prescription power SPH is negative, By reducing the comfort zone 15, the area of the stylish zone 16 can be increased. On the other hand, when the prescription frequency SPH is positive, if the frequency is large, the comfort zone 15 corresponding to the frequency becomes large and the area of the stylish zone 16 cannot be sufficiently secured. Therefore, the rotation angle β is preferably set to a constant value so that the area of the stylish zone 16 can be sufficiently secured.

  FIG. 12 shows the relationship between the design diameter (radius) DR of the comfort zone 15 and the prescription power SPH in the eyeglass lens 10 of this example, using the rotation angle β from the fitting point FP. When the prescription power SPH is negative, the stylish zone 16 is enlarged by adopting the rotation angle β that can secure the viewing angle α of 30 degrees theoretically determined by the prescription power SPH as the design diameter DR of the comfort zone 15. To do. On the other hand, when the prescription power SPH is plus (SPH is zero or more), the stylish zone 16 is secured by fixing the design diameter DR of the comfort zone 15 to the rotation angle β of 30 degrees.

  Therefore, as shown in FIG. 8, in step 22 for setting the design diameter DR of the comfort zone 15, if the prescription power SPH is negative in step 23, the absolute value of the prescription power SPH is determined in step 24. Increasing the value decreases the design diameter DR of the comfort zone (second region) 15. On the other hand, if the prescription frequency SPH is positive, in step 25, the design diameter DR of the comfort zone 15 is set to be constant regardless of the prescription frequency SPH.

  It is also possible to design a spectacle lens that prioritizes securing the viewing angle α for users who desire a feeling of wear rather than stylish performance. In that case, step 23 can be canceled and the design diameter DR of the comfort zone 15 can be adjusted by the prescription power SPH even when the prescription power SPH is positive in step 24. For example, as shown by a broken line in the graph of FIG. 12, the design diameter DR of the comfort zone 15 can be set to the rotation angle β corresponding to the prescription power SPH.

  Next, in step 26, it is confirmed whether or not the spectacle correction specification includes the astigmatism correction specification. When astigmatism correction is not included (step 26: YES, Y), the design diameter DR set in step 24 or step 25 is adopted. Since the spectacle lens 10 of this example is a rotationally symmetric aspherical surface, the shape of the comfort zone 15 designed based on the diameter DR is circular. When the specifications for astigmatism correction are included (step 26: NO, N), in step 27, for each astigmatism axis Ax, the same as step 22 based on the value obtained by adding the astigmatism power C to the prescription power SPH. Thus, the design diameter DR of the comfort zone 15 is obtained. Accordingly, when the spectacles specification includes an astigmatism correction specification, the frequency differs for each astigmatism axis Ax. Therefore, if even one astigmatism axis Ax has a negative value, the design of the comfort zone 15 on the astigmatism axis Ax is designed. The upper diameter DR is different from the design diameter DR in the other astigmatic axis Ax. Since the spectacle lens 10 of this example is rotationally symmetric, a comfort zone 15 having an elliptical design is set.

  The design diameter DR and the design shape are virtual diameters and shapes determined in a stage before designing the outer surface 11 and the inner surface 12 of the spectacle lens 10 with a smooth aspheric surface. Therefore, as will be described below, the aspherical surfaces for manufacturing the outer surface 11 and the inner surface 12 are determined, and the spectacle lens 10 manufactured according to them is reflected in the design diameter DR and the design shape. Although the optical properties remain, the design diameter DR and the design shape are not necessarily detected optically as they are.

  When the design diameter DR of the comfort zone 15 is determined in this way, in step 28, the aspheric surfaces of the outer surface 11 and the inner surface 12 that form the comfort zone 15 are designed. In the comfort zone 15, the correction of the average refractive power is prioritized over the correction of the astigmatism AS, the power error PE is small and almost 0 (zero), and the outer surface 11 has a prescription power SPH of spectacle specifications. And the inner surface 12 is determined. One example of such an outer surface 11 and an inner surface 12 is that the radial power MD (radial power error ME) and the circumferential power SD (circumferential power error SE) are mutually in the direction in which the rotation angle β increases. It changes to leave.

  In parallel with or before or after the design of the comfort zone 15, the aspheric surfaces of the outer surface 11 and the inner surface 12 forming the stylish zone 16 are designed in step 29. The stylish zone 16 is provided outside the comfort zone 15, and the design diameter DR of the comfort zone 15 varies depending on the prescription power SPH. Therefore, the range of the stylish zone 16 also varies depending on the prescription power SPH. However, in most prescription powers, the stylish zone 16 is included in the range of the rotation angle β of 20 degrees to 60 degrees. In the stylish zone 16, the correction of the astigmatism AS in the distance vision is prioritized over the correction of the average refractive power with respect to the prescription power SPH, and the astigmatism AS is 0 (zero) instead of accepting the power error PE to some extent. The outer surface 11 and the inner surface 12 are determined so as to approach.

  An example of the outer surface 11 and the inner surface 12 of the stylish zone 16 is such that the value of the astigmatism AS changes so as to have extreme values on the minus side and the plus side across 0 (zero). When the prescription power SPH is negative, the astigmatism AS is vibrated as an extreme value on the minus side, 0, and an extreme value on the plus side, so that the astigmatism AS converges to zero as much as possible. To design. For example, the outer surface 11 and the radial surface power MD (radial power error ME) and the circumferential power SD (circumferential power error SE) approach each other in the direction in which the rotation angle β increases and approach each other. The inner surface 12 can be designed. When the prescription power is negative, the outer surface 11 and the inner surface 12 can be designed to cross the circumferential power error SE on the positive side by changing the radial power error ME from the negative side to the positive side.

  In designing the outer surface 11 and the inner surface 12 of the stylish zone 16, it is desirable that the maximum error MPE of the allowable power error PE is within 30% of the prescription power SPH. The maximum error MPE is more preferably within 25% of the prescribed power SPH, and even more preferably within 20% of the prescribed power SPH. If the MPE in the stylish zone 16 exceeds 30%, the appearance of the stylish zone 16 is extremely deteriorated, and the function as a spectacle lens may not be achieved.

  Subsequently, in step 30, the aspheric surfaces of the outer surface 11 and the inner surface 12 of the spectacle lens 10 including the comfort zone 15 and the stylish zone 16 are designed. Specifically, the aspheric surfaces of the outer surface 11 and the inner surface 12 are obtained so that the aspheric surfaces of the zones 15 and 16 obtained in steps 28 and 29 are smoothly connected.

  Further, in step 31, the optical performance when viewed with the spectacle lens 10 having the outer surface 11 and the inner surface 12 obtained and the fashionability when viewed with the spectacle lens 10 are evaluated. When the spectacle lens 10 that satisfies the user's needs can be designed, the spectacle lens 10 having the outer surface 11 and the inner surface 12 designed in step 32 is manufactured.

(Example 2 and Comparative Example 2)
In FIG. 13A, an error (power error) PE of the average refractive power AvP with respect to the prescription power SPH of the eyeglass lens 10 of Example 2 is indicated by a two-dot chain line, and astigmatism AS for far vision is indicated by a broken line, and the radial direction The frequency error ME is indicated by a solid line, and the circumferential frequency error SE is indicated by a one-dot chain line. The eyeglass lens 10 of Example 2 is also a single focus lens having an outer surface 11 and an inner surface 12 that are rotationally symmetric aspheric surfaces, and is a spectacle lens for correcting hyperopia with a prescription power SPH of + 2.0D. Specific lens data is as follows.
Vertex power [D]: 2.00
External paraxial curvature (0) [D]: 3.97
External paraxial curvature (10) [D]: 3.79
External paraxial curvature (20) [D]: 3.23
External paraxial curvature (30) [D]: 2.42
Inner paraxial curvature (0) [D]: 2.00
Inner paraxial curvature (10) [D]: 1.99
Inner paraxial curvature (20) [D]: 1.80
Inner paraxial curvature (30) [D]: 1.49
Center thickness [mm]: 2.70

  This spectacle lens 10 also has a value of astigmatism AS on the plus side in a region where the rotation angle β of the eyeball is included in a range of 20 degrees to 60 degrees, specifically, in a region where the rotation angle β is larger than 30 degrees. It has an extreme value (as (+)), passes 0 (as (0)), and then changes to have an extreme value (as (-)) on the minus side. Further, along the direction in which the rotation angle β increases in this region, the radial power error ME and the circumferential power error SE change so as to approach each other after approaching and intersecting each other. In this example, the radial error ME shifted to the plus side shifts to the minus side and intersects the circumferential error SE. Therefore, in this region, the power error PE is about 20% when the rotation angle β is 50 degrees with respect to the prescription power SPH (2.0 D), but the astigmatism AS converges around 0 instead. It has been corrected as follows.

  On the other hand, in the region where the rotation angle β is smaller than 30 degrees, the radial power error ME and the circumferential power error SE change so as to be separated from each other in the direction in which the rotation angle β increases. Therefore, in this region, the power error PE is almost 0 and the astigmatism AS is also corrected well, but the astigmatism AS increases as the rotation angle β increases.

  Therefore, this spectacle lens 10 has a rotation angle β of 30 degrees as a boundary 17, and the outside (the one with the larger rotation angle β) is not far-sighted with respect to the correction of the average refractive power with respect to the prescription power SPH (power error PE). A first region (stylish zone) 16 in which correction of astigmatism AS is prioritized is formed, and the inner portion thereof, that is, the central portion of the spectacle lens 10 inside the boundary 17 has an average refractive power of the correction of astigmatism AS. The second area (comfort zone) 15 is prioritized for correction (power error PE).

In FIG. 13B, the error (power error) PE of the average refractive power AvP with respect to the prescription power SPH of the spectacle lens 19 of Comparative Example 2 is indicated by a two-dot chain line, the astigmatism AS in the distance vision is indicated by a broken line, and the radial direction The frequency error ME is indicated by a solid line, and the circumferential frequency error SE is indicated by a one-dot chain line. The spectacle lens 19 of Comparative Example 2 is also a single-focus lens having an outer surface 11 and an inner surface 12 with rotationally symmetric aspheric surfaces, and is a spectacle lens for correcting hyperopia with a prescription power SPH of + 2.0D. Specific lens data is as follows.
Vertex power [D]: 2.00
External paraxial curvature (0) [D]: 3.97
External paraxial curvature (10) [D]: 3.79
External paraxial curvature (20) [D]: 3.23
External paraxial curvature (30) [D]: 2.42
Inner paraxial curvature (0) [D]: 2.00
Inner paraxial curvature (10) [D]: 1.97
Inner paraxial curvature (20) [D]: 1.73
Inner paraxial curvature (30) [D]: 1.28
Center thickness [mm]: 2.70

  In the spectacle lens 19 of Comparative Example 2, the rotation angle β is in the range of 0 to 50 degrees, and the radial power error ME and the circumferential power error SE change so as to be separated from each other as the rotation angle β increases. ing. As a result, the power error PE is almost zero throughout the spectacle lens 19, and the astigmatism AS increases as the rotation angle β increases. Therefore, it can be said that the entire spectacle lens 19 is a comfort zone in which the correction of the average refractive power (power error PE) is prioritized over the correction of the astigmatism AS.

  In FIG. 13C, the distortion aberration of the eyeglass lens 10 of Example 2 is indicated by a solid line, and the distortion aberration of the eyeglass lens 19 of Comparative Example 2 is indicated by a broken line. It can be seen that distortion is improved in the peripheral portion of the lens, that is, in the stylish zone 16 of the eyeglass lens 10 of Example 2.

  As described above, even in a spectacle lens with a positive prescription power SPH, the power error PE and astigmatism AS are well corrected and a clear image can be obtained in the same manner as a spectacle lens with a negative prescription power SPH. A zone 15 is provided in the center, and a stylish zone 16 that includes astigmatism AS including 0 and vibrates in the vicinity of 0 (takes a value close to 0) is provided in the periphery instead of accepting the power error PE. Can do. Further, even in a spectacle lens having a positive prescription power SPH, by providing the stylish zone 16, both the performance in the peripheral portion when viewed with the spectacle lens 10 and the performance when viewed with the spectacle lens 10 are improved. I understand.

  Also, as shown in FIG. 14, in the stylish zone 16 of the spectacle lens 10, a certain amount of power error PE is allowed, so the options of the base curve 11 and the inner curve 12 are expanded. For example, as shown in FIG. 14A, the base curve 11 (solid line) of the eyeglass lens 10 of Example 2 is smaller at the periphery than the base curve 11 (dashed line) of the eyeglass lens 19 of Comparative Example 2 (curvature). Can increase the radius). Further, as shown in FIG. 14B, the curve 12 (solid line) on the inner surface of the spectacle lens 10 of Example 2 is larger at the peripheral portion than the curve 12 (broken line) on the inner surface of the spectacle lens 19 of Comparative Example 2. (The radius of curvature can be reduced). In either case, the spectacle lens 10 can be made thinner and lighter than the spectacle lens 19. Therefore, in this respect as well, the eyeglass lens 10 of Example 2 is suitable for users who place importance on the appearance.

  In the eyeglass lens 10 with a positive prescription power SPH in this example, the design diameter DR of the comfort zone 15 is set to 30 degrees as described in Step 22 of FIG. 8, but the viewing angle α is 30. It is also possible to widen the comfort zone 15 so as to be at the same degree. In that case, the stylish zone 16 becomes smaller, but the range in which the function of the comfort zone 16 can be obtained becomes wider.

(Example 3 and Comparative Example 3)
In FIGS. 15A and 15B, the error (power error) PE of the average refractive power AvP with respect to the prescription power SPH of the spectacle lens 10 of Example 3 is indicated by a two-dot chain line, and the astigmatism AS for far vision is indicated by a broken line. The radial direction power error ME is shown by a solid line, and the circumferential power error SE is shown by a one-dot chain line. The spectacle lens 10 of Example 3 is a spectacle lens including astigmatism correction having a prescription power SPH of −5.0 D, an astigmatism power C of −1.0 D, and an astigmatism axis Ax of 180 degrees. FIG. 15A shows changes in numerical values along the axis in the 90-degree direction, and FIG. 15B shows changes in numerical values in the 180-degree direction along the astigmatic axis Ax. Specific lens data is as follows.
Spherical power [D]: -5.00
Astigmatic power [D]: -1.00
Astigmatic axis: 180 degree external paraxial curvature (0) [D]: 1.00
External paraxial curvature (10) [D]: 0.98
External paraxial curvature (20) [D]: 0.82
External paraxial curvature (30) [D]: 0.50
180 degree direction Internal paraxial curvature (0) [D]: 6.00
180 degree direction Internal paraxial curvature (10) [D]: 5.62
180 degree direction Internal paraxial curvature (20) [D]: 4.32
180 degree direction Internal paraxial curvature (30) [D]: 2.52
90 degree direction Internal paraxial curvature (0) [D]: 7.00
90 degree direction Internal paraxial curvature (10) [D]: 6.60
90 degree direction Internal paraxial curvature (20) [D]: 5.15
90 degree direction Internal paraxial curvature (30) [D]: 3.12
Center thickness [mm]: 1.10

  In this spectacle lens 10, astigmatism correction is taken into consideration as shown in FIGS. 15A and 15B, each curve is complicated, but in terms of design, the rotation angle is 90 degrees. With β being about 24 degrees as a boundary 17, the outside is the stylish zone 16, and the inside is the comfort zone 15. In the 180 degree direction, the outer side is the stylish zone 16 and the inner side is the comfort zone 15 with the rotation angle β of about 26 degrees as the boundary 17.

  Therefore, as shown in FIG. 16, in the spectacle lens 10, as shown by a broken line, the design of the comfort zone 15 has a design diameter DR in the 90-degree direction 10a with the fitting point FP as the center. Is an ellipse having a short design diameter DR in the 180 ° direction 10b. Therefore, in the example of the other spectacle lens 10 that does not include astigmatism correction, the comfort zone 15 is different from a circle centered on the fitting point FP. However, the configurations of the comfort zone 15 and the stylish zone 16 are the same as those of the eyeglass lens 10 of the first embodiment.

In FIGS. 17A and 17B, the error (power error) PE of the average refractive power AvP with respect to the prescription power SPH of the spectacle lens 19 of Comparative Example 3 is indicated by a two-dot chain line, and the astigmatism AS for far vision is indicated by a broken line. The radial direction power error ME is shown by a solid line, and the circumferential power error SE is shown by a one-dot chain line. The spectacle lens 19 of Comparative Example 3 is a spectacle lens including astigmatism correction having a prescription power SPH of −5.0 D, an astigmatism power C of −1.0 D, and an astigmatism axis Ax of 180 degrees. FIG. 17A shows the change of each numerical value along the axis in the 90 degree direction, and FIG. 17B shows the change of each numerical value along the axis in the 180 degree direction. Specific lens data is as follows.
Spherical power [D]: -5.00
Astigmatic power [D]: -1.00
Astigmatic axis: 180 degree external paraxial curvature (0) [D]: 1.00
External paraxial curvature (10) [D]: 0.98
External paraxial curvature (20) [D]: 0.82
External paraxial curvature (30) [D]: 0.50
180 degree direction Internal paraxial curvature (0) [D]: 6.00
180 degree direction Internal paraxial curvature (10) [D]: 5.67
180 degree direction Internal paraxial curvature (20) [D]: 4.69
180 degree direction Internal paraxial curvature (30) [D]: 3.45
90 degree direction Internal paraxial curvature (0) [D]: 7.00
90 degree direction Internal paraxial curvature (10) [D]: 6.67
90 degree direction Internal paraxial curvature (20) [D]: 5.64
90 degree direction Internal paraxial curvature (30) [D]: 4.35
Center thickness [mm]: 1.10

  18A and 18B, the distortion aberration of the eyeglass lens 10 of Example 3 is indicated by a solid line, and the distortion aberration of the eyeglass lens 19 of Comparative Example 3 is indicated by a broken line. FIG. 18A shows a 90-degree direction, and FIG. 18B shows a 180-degree direction. In any axial direction, it can be seen that distortion is improved in the peripheral portion of the lens, that is, in the stylish zone 16 of the spectacle lens 10 of Example 3.

  As described above, even in the spectacle lens including the astigmatism correction in the spectacle specification, the power error PE and the astigmatism AS are well corrected, the comfort zone 15 in which a clear image can be obtained is provided in the center portion, and the power error PE Is acceptable, a stylish zone 16 having astigmatism AS including 0 and a value that vibrates in the vicinity of 0 can be provided in the peripheral portion. Also, in the spectacle lens for correcting astigmatism, by providing the stylish zone 16, both the performance at the periphery of the lens when viewed with the spectacle lens 10 and the performance when viewed with the spectacle lens 10 can be improved.

(Examples 4-9 and Comparative Examples 4-9)
In FIGS. 19A and 19B, the error (power error) PE of the average refractive power AvP with respect to the prescription power SPH of the spectacle lens 10 of Example 4 and the spectacle lens 19 of Comparative Example 4 is indicated by a two-dot chain line, and is viewed from a distance. Astigmatism AS is indicated by a broken line, a radial power error ME is indicated by a solid line, and a circumferential power error SE is indicated by a one-dot chain line. These lenses 10 and 19 are spectacle lenses for correcting myopia having a prescription power SPH of −8.0D. Further, in FIG. 19C, the distortion aberration of the eyeglass lens 10 of Example 4 is indicated by a solid line, and the distortion aberration of the eyeglass lens 19 of Comparative Example 4 is indicated by a broken line.

  In the eyeglass lens 10 of Example 4, the outer side is the stylish zone 16 and the inner side is the comfort zone 15 with the rotation angle β of about 24 degrees as the boundary 17.

  In FIGS. 20A and 20B, the error (power error) PE of the average refractive power AvP with respect to the prescription power SPH of the spectacle lens 10 of Example 5 and the spectacle lens 19 of Comparative Example 5 is indicated by a two-dot chain line, and far vision Astigmatism AS is indicated by a broken line, a radial power error ME is indicated by a solid line, and a circumferential power error SE is indicated by a one-dot chain line. These lenses 10 and 19 are spectacle lenses for correcting myopia having a prescription power SPH of −6.0D. In FIG. 20C, the distortion aberration of the eyeglass lens 10 of Example 5 is indicated by a solid line, and the distortion aberration of the eyeglass lens 19 of Comparative Example 5 is indicated by a broken line.

  In the eyeglass lens 10 of the fifth embodiment, the rotation angle β is about 25 degrees as a boundary 17, the outside is the stylish zone 16, and the inside is the comfort zone 15.

  In FIGS. 21A and 21B, the error (power error) PE of the average refractive power AvP with respect to the prescription power SPH of the spectacle lens 10 of Example 6 and the spectacle lens 19 of Comparative Example 6 is indicated by a two-dot chain line, and far vision Astigmatism AS is indicated by a broken line, a radial power error ME is indicated by a solid line, and a circumferential power error SE is indicated by a one-dot chain line. These lenses 10 and 19 are spectacle lenses for correcting myopia having a prescription power SPH of −4.0D. In FIG. 21C, the distortion aberration of the eyeglass lens 10 of Example 6 is indicated by a solid line, and the distortion aberration of the eyeglass lens 19 of Comparative Example 6 is indicated by a broken line.

  In the spectacle lens 10 of Example 6, the outer side is the stylish zone 16 and the inner side is the comfort zone 15 with the rotation angle β of about 26 degrees as the boundary 17.

  In FIGS. 22A and 22B, the error (power error) PE of the average refractive power AvP with respect to the prescription power SPH of the spectacle lens 10 of Example 7 and the spectacle lens 19 of Comparative Example 7 is indicated by a two-dot chain line, and far vision Astigmatism AS is indicated by a broken line, a radial power error ME is indicated by a solid line, and a circumferential power error SE is indicated by a one-dot chain line. These lenses 10 and 19 are spectacle lenses for correcting myopia having a prescription power SPH of −2.0D. In FIG. 22C, the distortion aberration of the eyeglass lens 10 of Example 7 is indicated by a solid line, and the distortion aberration of the eyeglass lens 19 of Comparative Example 7 is indicated by a broken line.

  In the eyeglass lens 10 of Example 7, the outer side is the stylish zone 16 and the inner side is the comfort zone 15 with the rotation angle β of about 28 degrees as the boundary 17.

  In FIGS. 23A and 23B, the error (power error) PE of the average refractive power AvP with respect to the prescription power SPH of the spectacle lens 10 of Example 8 and the spectacle lens 19 of Comparative Example 8 is indicated by a two-dot chain line, and is viewed from a distance. Astigmatism AS is indicated by a broken line, a radial power error ME is indicated by a solid line, and a circumferential power error SE is indicated by a one-dot chain line. These lenses 10 and 19 are spectacle lenses for correcting hyperopia having a prescription power SPH of + 4.0D. FIG. 23C shows the distortion aberration of the eyeglass lens 10 of Example 8 by a solid line, and the distortion aberration of the eyeglass lens 19 of Comparative Example 8 by a broken line.

  In the eyeglass lens 10 of Example 8, the rotation angle β is 30 degrees as a boundary 17, the outside is the stylish zone 16, and the inside is the comfort zone 15.

  In FIGS. 24A and 24B, the error (power error) PE of the average refractive power AvP with respect to the prescription power SPH of the spectacle lens 10 of Example 9 and the spectacle lens 19 of Comparative Example 9 is indicated by a two-dot chain line, and far vision Astigmatism AS is indicated by a broken line, a radial power error ME is indicated by a solid line, and a circumferential power error SE is indicated by a one-dot chain line. These lenses 10 and 19 are spectacle lenses for correcting hyperopia having a prescription power SPH of + 6.0D. FIG. 24C shows the distortion aberration of the eyeglass lens 10 of Example 9 by a solid line, and the distortion aberration of the eyeglass lens 19 of Comparative Example 9 by a broken line.

  In the eyeglass lens 10 of Example 9, the rotation angle β is 30 degrees as a boundary 17, the outside is the stylish zone 16, and the inside is the comfort zone 15.

  As shown in these examples, the spectacle lens 10 having the comfort zone 15 and the stylish zone 16 can be designed, manufactured and provided according to the present invention in a wide range where the prescription power SPH is on the minus side and the plus side. it can.

  In particular, in this example, the spectacle lens 10 having a negative prescription power SPH employs a design in which the comfort zone 15 is made smaller in accordance with the prescription power SPH included in the spectacle specification. For this reason, in the spectacle lens 10 in which the prescription power SPH is negative and the absolute value of the prescription power SPH is large, the comfort zone 15 can be reduced and the stylish zone 16 can be secured widely. Thereby, if the information of a wearer's prescription frequency is obtained, the comfort zone 15 can be set to a size suitable for the wearer. That is, it is not necessary to acquire special information from the wearer to design the comfort zone 15, and the eyeglass lens 10 of this example can be easily designed using a design device or the like based on general spectacle information. .

  The spectacle lens 10 having a negative prescription power SPH and a large absolute value is likely to have a thick rib, making it difficult to obtain a heavy and fashionable spectacle lens. By securing the stylish zone 16 widely, even a spectacle lens 10 with a negative prescription power SPH and a large absolute value can provide a spectacle lens 10 that is thin, light, and fashionable. In particular, it is effective to adopt a design in which the comfort zone 15 is made smaller in accordance with the prescription power SPH in the spectacle lens 10 having the prescription power SPH of −6.0D or less, and further, the prescription power SPH of −7.0D or less. is there.

  FIG. 25 shows an example of a spectacle lens design device 70. The design device 70 includes a unit 75 for acquiring spectacles specifications, a first unit 71 for designing the stylish zone 16, a second unit 72 for designing the comfort zone 15, and the stylish zone 16 and the comfort zone 15. It has the 3rd unit 73 which designs the inner surface 12 and the outer surface 11 of the spectacle lens 10, and the evaluation unit 74 which evaluates when the spectacle lens 10 designed is hung and seen.

  The second unit 72 for designing the comfort zone 15 further sets the design diameter DR of the area of the comfort zone 15 to be smaller as the absolute value of the prescription power SPH is larger when the prescription power SPH is negative. Adjustment unit 76 and a second adjustment unit 77 that keeps the design diameter DR of the comfort zone 15 constant regardless of the prescription power SPH when the prescription power SHP is positive. Furthermore, the second unit 72 includes a third adjustment unit 78 that adjusts the design diameter DR of the comfort zone 15 when the spectacle specification includes data for correcting astigmatism. The design device 70 can be mounted on an information processing device such as a personal computer including a CPU and a memory. Further, a program (program product) for realizing the function of the design device 70 by a computer can be stored in a memory such as a CD-ROM or provided via a computer network such as the Internet.

  The design device 70 acquires the spectacle specification of the user and designs the spectacle lens 10 including the comfort zone 15 and the stylish zone 16. At the same time, verifying the state that the user can see through the spectacle lens 10 when the spectacle lens 10 designed by the evaluation unit 74 is worn, and the state that can be seen by a third party when the user wears the spectacle lens 10. Can do. Therefore, the user can evaluate the use state of the designed spectacle lens 10 as well as the state when it is viewed, and is a spectacle lens having high fashionability that matches the user's own sensitivity. The eyeglass lens 10 that is easy to wear can be obtained.

  In the above description, the present invention is described using a single focus lens. However, the comfort zone 15 may be a progressive power lens including a distance portion suitable for far vision and a near portion suitable for near vision. . Further, both the inner surface and the outer surface may be aspherical surfaces, and either one of the surfaces may be aspherical surfaces. In the above description, an example is described in which the viewing angle α of the comfort zone 15 (particularly the viewing angle when the prescription power is negative) is set to 30 degrees, but the viewing angle α may be set to 30 degrees or less. , 30 degrees or more may be set.

DESCRIPTION OF SYMBOLS 1 Glasses, 5 Frame 10, 19 Eyeglass lens, 11 Outer surface (base curve), 12 Inner surface 15 Comfort zone (2nd area | region)
16 Stylish Zone (first area)

Claims (10)

A first region included in at least a part of a rotation angle of the wearer's eyeball from 20 degrees to 60 degrees;
A second region formed inside the first region;
Have
The spectacle lens, wherein the first region includes a point where an astigmatism value takes a negative extreme value and a point where the astigmatism value takes a positive extreme value. The spectacle lens according to claim 1.
The first region is
A spectacle lens including a region in which a radial power value and a circumferential power value change so as to approach each other after approaching and intersecting each other in a direction in which the rotation angle increases. The spectacle lens according to claim 1 or 2,
The spectacle lens, wherein the maximum error of the average refractive power with respect to the prescription power of the first region is 30% or less. The spectacle lens according to any one of claims 1 to 3,
The second region is
A spectacle lens including a region in which the value of the radial power and the value of the circumferential power change so as to be separated from each other in the direction in which the rotation angle increases. A first region included in at least a part of the rotation angle of the wearer's eyeball from 20 degrees to 60 degrees, and a second region formed inside the first region, The first region includes a spectacle lens including a point where the value of astigmatism takes a negative extreme value, and a point where the value of astigmatism takes a positive extreme value;
A spectacle frame to which the spectacle lens is attached;
Glasses with. Providing a first region included in at least a part of a range of 20 degrees to 60 degrees of the rotation angle of the wearer's eyeball;
Providing a second region inside the first region;
Including
The spectacle lens design method, wherein the first region includes a point where an astigmatism value takes a negative extreme value and a point where the astigmatism value takes a positive extreme value. In the design method of the spectacle lens according to claim 6,
Providing the second region includes reducing the design diameter of the second region as the absolute value of the prescription power is larger when the prescription power is negative. . In the design method of the spectacle lens according to claim 6 or 7,
Providing the second region includes designing the spectacle lens into an ellipse when the spectacle lens prescription includes astigmatism correction with a minus power. Method. An eyeglass lens design device,
A unit that acquires spectacles specifications including prescription frequency;
A first unit for designing a first region included in at least a part of a rotation angle of the wearer's eyeball from 20 degrees to 60 degrees;
A second unit for designing a second region located inside the first region;
Have
In the first unit, the first region is designed to include a point where an astigmatism value takes a negative extreme value and a point where the astigmatism value takes a positive extreme value. , Design equipment. The design device according to claim 9,
When the prescription power is negative, the second unit decreases the design diameter of the second region as the absolute value of the prescription power is large, and when the prescription power is positive, A design apparatus including a unit that makes a design diameter of the second region constant regardless of a prescription frequency.