JP2013101323A - Multifocal ocular lens - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multifocal ocular lens that ensures clear far vision and near vision even in a bright place where a pupil diameter becomes smaller, has a satisfactory field of view at an intermediate position between the far and near positions, and is appropriate to suppress degradation in imaging performance resulting from occurrence of flare.SOLUTION: A multifocal ocular lens has a ring band structure in which at least one surface is divided into a plurality of concentric circular refractive surfaces. The multifocal ocular lens has a step in a direction substantially horizontal to an optical axis between adjacent refractive surfaces. The height of the step satisfies a predetermined condition. Also, of the two refractive faces adjacent to each other, the refractive surface far from the optical axis is defined as an outside refractive surface, and the refractive surface close to the optical axis is defined as an inside refractive surface. In this case, the multifocal ocular lens is configured to have at least one structure in which the curvature radius of the outside refractive surface has a value between the curvature radius of the inside refractive surface and the curvature radius of a base-curve shape so as to become closer to the base-curve shape.

Description

  The present invention relates to a multifocal ophthalmic lens prescribed for the eye.

  For the purpose of treating cataracts, surgery for removing a turbid lens and inserting an intraocular lens (Intraocular Lens, IOL) has become widespread. In this type of surgery, a multifocal intraocular lens is inserted to compensate for the adjustment power lost by removing the lens. Multifocal intraocular lenses include a refractive type with a distance or near power assigned to each area, and a diffractive structure type that distributes the power to the distance and the near power. Vision, near vision). In other words, the multifocal intraocular lens is designed to ensure visual acuity at both the far and near focusing points so that the lens wearer can send his / her daily life without glasses. Specific configuration examples of this type of multifocal intraocular lens are described in Patent Document 1 and Patent Document 2.

  Patent Document 1 describes a refractive multifocal intraocular lens that is divided into dedicated zones for each power, such as distance and near. This type of refractive multifocal intraocular lens has a problem that the effect of multifocal changes greatly depending on the pupil diameter of the lens wearer. For example, consider a case where the wearer of the refractive multifocal intraocular lens described in Patent Document 1 is outdoors in fine weather. In this case, the diameter of the light beam incident on the intraocular lens is limited to the distance zone by reducing the pupil diameter of the lens wearer. Therefore, the lens wearer can substantially only view from a distance.

  On the other hand, in the diffractive structure type, the change of the multifocal effect depending on the pupil diameter can be suppressed. Patent Document 2 describes a diffractive structure type multifocal intraocular lens in which an apodized diffractive structure is formed at the center of one side of the lens. In the diffractive structure type multifocal intraocular lens described in Patent Document 2, there is no situation in which it is difficult to view near when the pupil diameter is reduced. However, since the number of steps is large, a lot of unnecessary light is generated, resulting in noise (flares) that spreads over a wide range of the field of view, and the imaging performance deteriorates. Moreover, since there is substantially no light quantity distributed to the middle position between the far and near places, the middle position cannot be clearly seen.

Japanese Patent No. 2935750 Japanese Patent No. 3333989

  The present invention has been made in view of the above circumstances, and ensures a clear distance vision and near vision even in a bright place where the pupil diameter is small, and also has a good visual field at an intermediate position between the distance and the near. And providing a multifocal ophthalmic lens suitable for suppressing deterioration in imaging performance due to the occurrence of flare. Note that the present invention is not limited to an intraocular lens, but can be applied to another type of ophthalmic lens such as a contact lens. Therefore, in the above, it is described as a multifocal “eye” lens.

A multifocal ophthalmic lens according to an embodiment of the present invention that solves the above-described problems has an annular structure in which at least one surface is divided into a plurality of concentric refracting surfaces, and light is transmitted between adjacent refracting surfaces. A step in a direction substantially horizontal to the shaft is formed. The annular structure is added to the base curve shape. Such multifocal ophthalmic lens, the height of the step D (unit: [mu] m) is defined to be the refractive index of the multifocal ophthalmic lens in the e-line is defined as n _1, the refractive index of water at e-line n _When defined as ₀ , the following condition (1)
0.190 <| D × (n ₁ −n ₀ ) | <0.370 (1)
Of the two adjacent refracting surfaces, the outer refracting surface is defined as the outer refracting surface, and the refracting surface closer to the optical axis is defined as the inner refracting surface. It is characterized by having at least one structure having a value between the curvature radius of the inner refractive surface and the curvature radius of the base curve shape so that the curvature radius of the curve approaches the base curve shape.

In addition, a multifocal ophthalmic lens according to another embodiment of the present invention that solves the above-described problem has an annular structure in which at least one surface is divided into a plurality of concentric refracting surfaces, and includes refracting surfaces adjacent to each other. A step in the direction substantially horizontal to the optical axis is formed therebetween. The annular structure is added to the base curve shape. Such multifocal ophthalmic lens, the height of the step D (unit: [mu] m) is defined to be the refractive index of the multifocal ophthalmic lens in the e-line is defined as n _1, the refractive index of water at e-line n A function φ (h) that is defined as ₀ and that expresses the function due to the step of the Fresnel lens shape added to the base curve shape in the form of an optical path length addition amount at a height h (unit: mm) from the optical axis. ), The second-order and fourth-order optical path difference function coefficients are defined as P ₂ and P ₄ , respectively, and the blazed wavelength that gives the optical path length difference for one wavelength when assuming the refractive index at the e-line at the step It is defined as λ _B (unit: μm), and a constant term for setting the phase on the optical axis of the annular zone is P ₀ (takes an arbitrary number in the range of −0.5 ≦ P ₀ <0.5). And ROUND (X, Y) is a function that gives a value obtained by rounding X to the nearest Y decimal place. When
φ (h) = (P ₀ + P ₂ · h ² + P ₄ · h ⁴ −ROUND (P ₀ + P ₂ · h ² + P ₄ · h ⁴ , 1)) × λ _B
λ _B = | D × (n ₁ −n ₀ ) |
While satisfying
Next condition (2)
−0.40 <P ₄ / P ₂ <−0.01 (2)
It is characterized by satisfying.

In addition, a multifocal ophthalmic lens according to another embodiment of the present invention that solves the above-described problem has an annular structure in which at least one surface is divided into a plurality of concentric refracting surfaces, and includes refracting surfaces adjacent to each other. A step in the direction substantially horizontal to the optical axis is formed therebetween. The annular structure is added to the base curve shape. Such a multifocal ophthalmic lens includes a first annular zone step closest to the optical axis and a second annular zone step outside the first annular zone step in a direction perpendicular to the optical axis. Is defined as (a ₂ −a ₁ ), and the arrangement interval in the direction perpendicular to the optical axis between the outermost final step in the annular zone structure and the first inner step inside one of the final steps is defined as (A _last −a _last−1 ), and the arrangement interval between the first inner step and the second inner step inside the first inner step in the direction perpendicular to the optical axis is (a _last−1. -A _last-2 ), the following conditions (3) and (4)
0.25 <(a _last −a _last−1 ) / (a ₂ −a ₁ ) <2.00 (3)
1.00 <(a _last -a _last-1 ) / (a _last-1 -a _last-2 ) <3.00 (4)
Is satisfied at the same time.

In the multifocal ophthalmic lens according to the present invention, the curvature radius of the base curve shape is defined as Rbase (unit: mm), and the curvature radius of the refracting surface including the optical axis in the annular structure is R1 (unit: mm). The following condition (5)
| R1-Rbase |> | Ra-Rbase | (5)
The first outer refracting surface having a radius of curvature Ra (unit: mm) that satisfies the condition is outside the refracting surface including the optical axis, and the following condition (6)
| Ra-Rbase |> | Rb-Rbase | (6)
The second outer refracting surface having a curvature radius Rb (unit: mm) that satisfies the above condition may be outside the first outer refracting surface.

  Here, the second outer refracting surface is, for example, the outermost refracting surface of the annular structure, and the first outer refracting surface is adjacent to the inner side of the second outer refracting surface.

In the multifocal ophthalmic lens according to another aspect described above, the height of the step is defined as D (unit: μm), the refractive index of the multifocal ophthalmic lens at the e-line is defined as n _1, and When the refractive index of water is defined as n ₀ , the following condition (1)
0.190 <| D × (n ₁ −n ₀ ) | <0.370 (1)
May be satisfied.

  The multifocal ophthalmic lens according to the present invention may have a configuration in which the outermost final annular zone of the annular zone structure is smoothly connected to a base curve shape positioned outside the final annular zone.

In addition, a multifocal ophthalmic lens according to another embodiment of the present invention that solves the above-described problems has a concentric periodic structure formed on at least one surface. The periodic structure is an annular structure in which a plurality of uneven shapes with different periods added to the base curve shape are repeatedly arranged in the radial direction of the multifocal ophthalmic lens. Such multifocal ophthalmic lens, the difference between the minimum thickness and the maximum thickness of the optical axis direction of the periodic structure Dm (unit: [mu] m) is defined to be the refractive index of the multifocal ophthalmic lens in e-ray and n ₁ Definition When the refractive index of water at the e-line is defined as n ₀ , the following condition (7)
0.190 <| Dm × (n ₁ −n ₀ ) | <0.370 (7)
Of the two periods adjacent to each other, the period far from the optical axis is defined as the outer period, and the period closer to the optical axis is defined as the inner period. It has at least one wide structure.

The multifocal ophthalmic lens according to the present invention is, for example, a resin molded product. In this case, the refractive index n ₁ of the multifocal ophthalmic lens is, for example, the following condition (8)
1.38 <n1 <1.75 (8)
Meet.

The multifocal ophthalmic lens according to the present invention has the light convergence position where the diffraction efficiency is maximum in the annular structure when the e-ray light beam is incident at an incident light beam diameter of 2.0 mm, and the diffraction efficiency is second. When the absolute value of the addition power obtained from the high light convergence position is defined as L (unit: Dptr), the following condition (9)
1.0 <L <5.0 (9)
It is good also as composition which satisfies.

In the multifocal ophthalmic lens according to the present invention, when the pupil height (end position of the annular zone structure) of the connection position between the outermost final annular zone of the annular zone structure and the base curve shape is defined as hmax, Condition (10)
1.2 <hmax <4.0 (10)
It is good also as composition which satisfies.

  According to the present invention, clear distance vision and near vision can be ensured even in a bright place where the pupil diameter is small, the visual field at the intermediate position between the distance and the distance is good, and concomitant with the occurrence of flare. A multifocal ophthalmic lens suitable for suppressing degradation of image performance is provided.

It is a sectional side view of the multifocal ophthalmic lens of embodiment of this invention. It is a sectional structure figure of a contact lens of an embodiment of the present invention. The figure for demonstrating each arrangement | positioning space | interval of each ring zone is shown. It is a figure which shows the shape and optical performance of the multifocal ophthalmic lens of Example 1 of this invention. It is a figure which shows the shape and optical performance of the multifocal ophthalmic lens of Example 2 of this invention. It is a figure which shows the shape and optical performance of the multifocal ophthalmic lens of Example 3 of this invention. It is a figure which shows the shape and optical performance of the multifocal ophthalmic lens of Example 4 of this invention. It is a figure which shows the shape and optical performance of the multifocal ophthalmic lens of Example 5 of this invention. It is a figure which shows the shape and optical performance of the multifocal ophthalmic lens of Example 6 of this invention. It is a figure which shows the shape and optical performance of the multifocal ophthalmic lens of Example 7 of this invention. It is a figure which shows the shape and optical performance of the multifocal ophthalmic lens of Example 8 of this invention. It is a figure which shows the shape and optical performance of the multifocal ophthalmic lens of Example 9 of this invention. It is a figure which shows the shape and optical performance of the multifocal ophthalmic lens of the comparative example 1. It is a figure which shows the shape and optical performance of the multifocal ophthalmic lens of the comparative example 2. It is a sectional side view of the multifocal ophthalmic lens of embodiment of this invention.

  Hereinafter, a multifocal ophthalmic lens according to an embodiment of the present invention will be described with reference to the drawings.

The present invention can be applied to both contact lenses and IOLs. FIG. 1A and FIG. 15A are side sectional views showing an embodiment of a contact lens 1x designed by applying the present invention. FIG. 1B and FIG. It is a sectional side view showing one embodiment of IOL1y designed by applying the present invention. In this specification, multifocal ophthalmic lenses designed by applying the present invention, including the contact lenses 1x and IOL1y, are collectively referred to as “multifocal ophthalmic lenses 1”. The multifocal ophthalmic lens 1 is, for example, a resin molded product formed of a material having a refractive index n ₁ that satisfies the following condition (8).
1.38 <n1 <1.75 (8)
As a material used for the multifocal ophthalmic lens 1, for example, silicone, acrylic resin, Hydroxyethyl Methacrylate (HEMA) or the like is assumed.

  As shown in FIG. 1A and FIG. 1B, the multifocal ophthalmic lens 1 of the present embodiment has a rotationally symmetric shape around the optical axis, and a plurality of concentric refractions. An annular structure divided into planes is formed on one side. The annular zone structure is added to the base curve shape, and a step in a direction substantially horizontal to the optical axis is formed between adjacent refracting surfaces. However, the annular structure is not formed on the entire surface. The peripheral portion of the multifocal ophthalmic lens 1 has a base curve shape instead of an annular structure. The outermost final annular zone of the annular zone structure is smoothly connected to a base curve shape located outside the final annular zone. That is, the refractive surface of the last annular zone and the base curve shape (refractive surface) are continuously connected without any step. “Continuous connection without a step” refers to a state where the angle formed by the tangent to the refracting surface of the final ring zone and the tangent to the base curve surface is an obtuse angle. By reducing the level difference between the final ring zone and the base curve shape, the occurrence of flare due to the level difference structure can be effectively suppressed. The annular structure is not limited to one surface, and may be provided so as to be shared by each surface.

  As shown in FIG. 1A, the contact lens 1x has a first surface Rx1 and a second surface Rx2. When the contact lens 1x is worn, the first surface Rx1 is located on the object side, and the second surface Rx2 is located on the image side. In the contact lens 1x, a ring zone structure is provided on the second surface Rx2 side. Further, as illustrated in FIG. 1B, the IOL 1y has a first surface Ry1 and a second surface Ry2. When the IOL 1y is worn, the first surface Ry1 is located on the object side, and the second surface Ry2 is located on the image side. In the IOL 1y, a ring zone structure is provided on the first surface Ry1 side.

  FIG. 2 is a diagram for explaining various definitions, and shows a cross-sectional structure diagram of the contact lens 1x. In FIG. 2, the vertical axis indicates the sag amount (unit: mm), and the horizontal axis indicates the pupil height h (unit: mm). In FIG. 2, the solid line indicates the actual shape (the shape of the second surface Rx2), and the dotted line indicates the base curve shape. Further, the lower side of the solid line is the lacrimal fluid side, and the upper side of the solid line is the lens body side. In FIG. 2, the position of the step with respect to the optical axis (distance from the optical axis) is defined as the step position a (unit: mm), and the height of the step in the optical axis direction is the step height D (unit: μm). It is defined as Here, the step height D has a positive sign in the direction in which the lens body becomes thick. Further, a positive sign is attached to the lower shape deviation (shape error) in FIG. 2 with respect to the base curve, and a negative sign is assigned to the upper shape deviation (shape error) in FIG. 2 with respect to the base curve.

The annular structure is also referred to as a diffractive structure that imparts a diffractive action. The annular structure is, for example, a blazed diffraction structure having a sawtooth shape, and can be expressed by the following optical path difference function (h). The optical path difference function (h) is a function expressing the function as a diffractive lens having an annular structure in the form of an added optical path length at a height h (unit: mm) from the optical axis. Specify the installation position of. The optical path difference function (h), the secondary, quaternary, next six, P ₂ the optical path difference function coefficient of ... _{respectively,} P 4, _{P 6,} is defined as ..., diffraction efficiency of the light of wavelength λ When the diffraction order that maximizes is defined as m, it is expressed by the following equation.
Optical path difference function (h) = (P ₂ h ² + P ₄ h ⁴ + P ₆ h ⁶ + P ₈ h ⁸ + P ₁₀ h ¹⁰ + P ₁₂ h ¹² ) mλ

  Here, the conventional multifocal ophthalmic lens divides an incident light beam and collects it on the far vision side condensing point and the near vision side condensing point, respectively. However, this presents a problem that the patient cannot clearly see the intermediate position between the far vision side focusing point and the near vision side focusing point. Therefore, the multifocal ophthalmic lens 1 of the present embodiment divides an incident light beam and collects it at an intermediate position in addition to the far vision side condensing point and the near vision side condensing point. The depth of field is deepened so that the intermediate position can be clearly seen.

Specifically, multifocal ophthalmic lens 1 of this embodiment, the multifocal refractive index of the ophthalmic lens 1 at the design wavelength (e-ray (546 nm)) is defined as n _1, the refractive index of water at e-line Is defined as n ₀ , the following condition (1)
0.190 <| D × (n ₁ −n ₀ ) | <0.370 (1)
It is configured to satisfy.

  In the multifocal ophthalmic lens 1 of the present embodiment, in order to perform far vision and near vision, an addition power for adding a difference between the near power and the far power addition power is added using the first order diffraction order. It is necessary to design so that the diffraction efficiencies of the 1st-order diffracted light and the 0th-order diffracted light are balanced within a certain range at the e-line. However, if the lower limit of the condition (1) is not reached, the diffraction efficiency of the 0th-order diffracted light becomes too low (for example, less than 20%), and thus far vision (or near vision) becomes difficult due to insufficient light quantity. If the upper limit of the condition (1) is exceeded, the diffraction efficiency of the first-order diffracted light becomes too low (for example, less than 20%), and near vision (or far vision) becomes difficult due to insufficient light quantity. When the condition (1) is satisfied, it is possible to clearly see both far and near.

  In the multifocal ophthalmic lens 1 of the present embodiment, among the two refracting surfaces adjacent to each other in the annular structure, the refracting surface far from the optical axis is defined as the outer refracting surface, and the refracting near the optical axis When a surface is defined as an inner refractive surface, a structure having a value between the radius of curvature of the inner refractive surface and the radius of curvature of the base curve shape is set so that the radius of curvature of the outer refractive surface approaches the shape of the base curve. It is configured to have at least one.

  In this way, the outer ring zone has a configuration in which the gap between the steps is wider, so that the diffraction power that has been distributed to the near (or far) is weakened, and the near vision side condensing until now. A part of the light collected at the point (or the far vision side condensing point) is condensed at an intermediate position between the far vision side condensing point and the near vision side condensing point. Therefore, the patient can clearly see the intermediate position. That is, the inventor of the present invention at the time of filing the present patent application that the interval between the steps of the zonal structure imparted to the base curve shape is constant or narrower toward the outside in the technical field of multifocal ophthalmic lenses. A multifocal ophthalmic lens with a deep depth of field that breaks the shell of common sense and the outer ring zone has wider gaps between steps, making it possible to see clearly in the far, middle, and near distances. Realized. It should be noted that the condensing point at the intermediate position approaches the focal position of the base curve as the radius of curvature of the outer refractive surface approaches the curvature radius of the base curve shape. Further, as the distance between the steps increases, the total number of steps in the ring zone structure decreases, so that the occurrence of flare is reduced. Thus, according to the multifocal ophthalmic lens 1 of the present embodiment, clear distance vision and near vision are ensured even in a bright place where the pupil diameter is small, and an intermediate position between the distance and the near distance. The field of view is also good, and the deterioration of the imaging performance due to the occurrence of flare can be suppressed.

The configuration of the multifocal ophthalmic lens 1 of the present embodiment can also be expressed as follows. Specifically, the multifocal ophthalmic lens 1 has the function of the step difference of the Fresnel lens shape added to the base curve shape, and the optical path length addition amount at the pupil height h (unit: mm) from the optical axis. The second and fourth order optical path difference function coefficients are defined as P ₂ and P ₄ , respectively, when the refractive index at the e-line is assumed at each step. The blazed wavelength that gives the optical path length difference is defined as λ _B (unit: μm), and a constant term for setting the phase on the optical axis of the Fresnel lens-shaped annular zone is P ₀ (−0.5 ≦ P ₀ < And any number in the range of 0.5.), And ROUND (X, Y) is a function that gives a value obtained by rounding X to the Yth decimal place,
φ (h) = (P ₀ + P ₂ · h ² + P ₄ · h ⁴ −ROUND (P ₀ + P ₂ · h ² + P ₄ · h ⁴ , 1)) × λ _B
λ _B = | D × (n ₁ −n ₀ ) |
While satisfying
Next condition (2)
−0.40 <P ₄ / P ₂ <−0.01 (2)
It is configured to satisfy. The pupil height h at which the value of (P ₀ + P ₂ · h ² + P ₄ · h ⁴ −ROUND (P ₀ + P ₂ · h ² + P ₄ · h ⁴ , 1)) is 0.5 corresponds to the boundary of the annular zone. . The multifocal ophthalmic lens 1 has a Fresnel lens-like annular zone structure by adding a gradient and a step to the base curve shape so as to have an optical path difference of the function φ (h).

  Here, the fact that the optical path difference function coefficient P4 that defines the optical action similar to the spherical aberration takes the opposite sign of the optical path difference function coefficient P2 that defines the diffraction power means that the distance between the steps in the outer annular zone is larger. It means having a wide structure. Therefore, also in this example, the patient can clearly see the intermediate position. Further, as the distance between the steps increases, the total number of steps in the ring zone structure decreases, so that the occurrence of flare is reduced.

  In the above, if the lower limit of the condition (2) is not reached, the power change (change from the near power to the intermediate power through the intermediate power) given by the zonal structure is abrupt. The diameter of the ring zone structure distributed to the position is reduced. For this reason, the amount of light at the intermediate position is significantly insufficient, and a sufficient depth of field cannot be obtained. Further, if the upper limit of the condition (2) is exceeded, the frequency change becomes too gradual, resulting in an increase in the diameter of the entire ring zone structure. In this case, the amount of light at the intermediate position is greatly insufficient, and a sufficient depth of field cannot be obtained. In particular, the amount of light at the intermediate position is further insufficient for elderly people who cannot open a large pupil diameter. When the condition (2) is satisfied, it is possible to clearly see far, middle and near, and a sufficient depth of field can be obtained.

  In the multifocal ophthalmic lens 1 of this example, it is more preferable that the condition (1) is satisfied.

Moreover, the structure of the multifocal ophthalmic lens 1 of this embodiment can also be expressed as follows. Specifically, in the multifocal ophthalmic lens 1, the arrangement interval in the direction perpendicular to the optical axis between the first annular step and the second annular step of the annular structure is defined as (a ₂ −a ₁ ). The arrangement interval between the final step and the first inner step in the direction orthogonal to the optical axis is defined as (a _last −a _last-1 ), and the optical axis between the first inner step and the second inner step is When the arrangement interval in the orthogonal direction is defined as (a _last-1 −a _last-2 ), the following conditions (3) and (4)
0.25 <(a _last −a _last−1 ) / (a ₂ −a ₁ ) <2.00 (3)
1.00 <(a _last -a _last-1 ) / (a _last-1 -a _last-2 ) <3.00 (4)
It is comprised so that it may satisfy | fill simultaneously.

FIG. 3 is a diagram for explaining each arrangement interval. The vertical axis in FIG. 3 is the ring zone structure added to the base curve (according to another expression, the shape deviation (shape error) with respect to the base curve, and the base curve component is subtracted from the ring zone structure forming surface. The horizontal axis represents the incident light beam radius (unit: mm). As shown in FIG. 3, the first annular zone step and the second annular zone step that define the arrangement interval (a ₂ −a ₁ ) are one of the step closest to the optical axis and the first annular zone step, respectively. This is the outer step. In addition, the final step and the first inner step that define the arrangement interval (a _last −a _last−1 ) are the outermost step of the annular zone structure and the step inside one of the final steps, respectively. Further, the second inner step defining the arrangement interval (a _last-1 −a _last-2 ) is a step inside one of the first inner steps. As shown in FIG. 3, the final step and the base curve shape are smoothly connected at the connection point (ring zone end position hmax in FIG. 3).

  If the lower limit of the condition (3) is not reached, the peripheral power change is abrupt with respect to the vicinity of the center, and as a result, the diameter of the annular zone structure distributed to the intermediate position becomes small. For this reason, the amount of light at the intermediate position is significantly insufficient, and a sufficient depth of field cannot be obtained. If the upper limit of the condition (3) is exceeded, the power near the center is very strong and the power change around the center becomes too gradual, resulting in an increase in the diameter of the entire ring zone structure. In this case, even if the pupil is widened, the amount of light distributed to the intermediate area is insufficient, and a sufficient depth of field cannot be obtained. Further, when the size of the pupil diameter is not so large as in an elderly person, the influence is even greater. When the condition (3) is satisfied, it can be clearly seen even when the pupil diameters in the far, middle, and near distances change, and a sufficient depth of field can be obtained.

  If the lower limit of the condition (4) is not reached, the frequency change is abrupt, and as a result, the diameter of the annular zone structure having a progressive effect is reduced. For this reason, the amount of light at the intermediate position is significantly insufficient, and a sufficient depth of field cannot be obtained. Further, if the upper limit of the condition (4) is exceeded, the frequency change becomes too gradual, and as a result, the diameter of the entire ring zone structure becomes large. In this case, the amount of light at the intermediate position is greatly insufficient, and a sufficient depth of field cannot be obtained. In particular, the amount of light at the intermediate position is further insufficient for elderly people who cannot open a large pupil diameter. When the condition (4) is satisfied, it is possible to clearly see far, middle and near, and a sufficient depth of field can be obtained.

  In the multifocal ophthalmic lens 1 of this example, it is more preferable that the condition (1) is satisfied.

In the multifocal ophthalmic lens 1 of the above three examples, the radius of curvature of the base curve shape is defined as Rbase (unit: mm), and the radius of curvature of the refracting surface including the optical axis in the annular structure is R1 (unit: mm). )), The following condition (5)
| R1-Rbase |> | Ra-Rbase | (5)
The first outer refracting surface having a radius of curvature Ra (unit: mm) that satisfies the condition is outside the refracting surface including the optical axis, and the following condition (6)
| Ra-Rbase |> | Rb-Rbase | (6)
The second outer refracting surface having a curvature radius Rb (unit: mm) that satisfies the above condition may be outside the first outer refracting surface. Further, the second outer refracting surface may be, for example, the outermost refracting surface of the annular structure, and the first outer refracting surface may be adjacent to the inner side of the second outer refracting surface.

Each of the three examples of the annular structure is a kind of so-called blazed diffractive structure having a sawtooth shape. However, in the modification of the present embodiment, a periodic structure type zonal structure is used instead of the blazed diffractive structure. You may apply. Specifically, the periodic structure of the multifocal ophthalmic lens 1 of the modified example is a concentric annular zone structure added to the base curve shape, and a plurality of concave and convex shapes having different periods are used for the multifocal eye. The lens 1 is repeatedly arranged in the radial direction. When the difference between the minimum thickness and the maximum thickness in the optical axis direction of the periodic structure is defined as Dm (unit: μm), the multifocal ophthalmic lens 1 of the modified example has the following condition (7)
0.190 <| Dm × (n ₁ −n ₀ ) | <0.370 (7)
It is configured to satisfy.

  Also in the multifocal ophthalmic lens 1 of the modified example, in order to perform far vision and near vision, the addition power for adding the difference between the addition power for the near vision and the far vision using the first diffraction order is added. It is necessary to design so that the diffraction efficiencies of the next-order diffracted light and the 0th-order diffracted light are balanced within a certain range at the e-line. However, if the lower limit of the condition (7) is not reached, the diffraction efficiency of the 0th-order diffracted light becomes too low (for example, less than 20%), and thus far vision (or near vision) becomes difficult due to insufficient light quantity. If the upper limit of condition (7) is exceeded, the diffraction efficiency of the first-order diffracted light becomes too low (for example, less than 20%), and near vision (or far vision) becomes difficult due to insufficient light quantity. When the condition (7) is satisfied, it is possible to clearly see both far and near.

  In the multifocal ophthalmic lens 1 according to the modified example, of two periods adjacent to each other in the periodic structure, a period far from the optical axis is defined as an outer period, and a period closer to the optical axis is defined as an inner period. In this case, at least one structure in which the outer period is wider than the inner period is configured.

  In this way, by providing a structure with a wider outer period (irregularity formation interval), the diffraction power that has been distributed for near use becomes weaker, and the light is focused on the near vision side condensing point until now. Part of the light that has been collected also converges at an intermediate position between the far vision side condensing point and the near vision side condensing point. Therefore, the patient can clearly see the intermediate position. In addition, as the period increases, the total number of concave and convex shapes decreases, and flare is reduced. As described above, according to the multifocal ophthalmic lens 1 of the modified example, clear distance vision and near vision can be ensured even in a bright place where the pupil diameter is small, and an intermediate position between the distance and the near distance is secured. The field of view is good, and the deterioration of imaging performance due to the occurrence of flare can be suppressed.

In addition, the multifocal ophthalmic lens 1 of the present embodiment has a diffraction efficiency with an annular structure when an e-ray light beam is incident with an incident light beam diameter of 2.0 mm (e.g., corresponding to the pupil diameter of a patient in a bright place). L is the absolute value of the addition power obtained from the convergence position of the light that maximizes the light and the convergence position of the light having the second highest diffraction efficiency (that is, the far vision side focusing position and the near vision side focusing position). : Dptr), the following condition (9)
1.0 <L <5.0 (9)
It is good also as composition which satisfies.

  If the lower limit of the condition (9) is not reached, a sufficient near vision power cannot be obtained, so near vision cannot be achieved. On the other hand, if the upper limit of the condition (9) is exceeded, the near vision power is too high, and there is a possibility of causing eye strain on the contrary.

Further, in the multifocal ophthalmic lens 1 of the present embodiment, the pupil height (end position of the annular zone structure) of the connection position between the outermost final annular zone of the annular zone structure and the base curve shape is defined as hmax. In the following condition (10)
1.2 <hmax <4.0 (10)
It is good also as composition which satisfies.

  If the lower limit of the condition (10) is not reached, the diameter of the entire ring zone structure is too small, and as a result, the frequency change becomes abrupt. For this reason, the amount of light at the near and intermediate positions is significantly insufficient, and a sufficient depth of field cannot be obtained. If the upper limit of the condition (10) is exceeded, the diameter of the entire ring zone structure is too large, and the frequency change becomes too gradual. In this case, the amount of light at the intermediate position is greatly insufficient, and a sufficient depth of field cannot be obtained. In particular, the amount of light at the intermediate position is further insufficient for elderly people who cannot open a large pupil diameter. When the condition (10) is satisfied, it is possible to clearly see far, middle and near, and a sufficient depth of field can be obtained.

Next, nine specific numerical examples of the multifocal ophthalmic lens 1 described so far will be described. The multifocal ophthalmic lenses 1 of Examples 1 to 7 of the present invention are of a type having a blazed diffractive structure, and the multifocal ophthalmic lenses 1 of Examples 8 and 9 have a periodic structure type annular zone structure. It is a type that has.
In addition, the multifocal ophthalmic lens 1 of Examples 5 and 6 is an IOL, and the multifocal ophthalmic lens 1 of other examples is a contact lens. FIG. 1A is used as a schematic lens cross-sectional view of the multifocal ophthalmic lens 1 of Examples 1-4, 8, and 9. For the multifocal ophthalmic lens 1 of Examples 5 and 6, FIG. FIG. 15A is referred to for the multifocal ophthalmic lens 1 of the seventh embodiment. Table 1 shows specific numerical configurations of Examples 1 to 9. In Table 1, “switching position” indicates the pupil height (unit: mm) at which the change from the near power to the intermediate power starts. In Table 1, the first surface base curve (unit: mm) represents the base curve of the object side surface, and the second surface base curve (unit: mm) represents the base curve of the image side surface. The center thickness (unit: mm) indicates the thickness of the multifocal ophthalmic lens 1 on the optical axis.

  In the present embodiment, FIG. 1A and FIG. 1B, FIG. 15A and FIG. 15B are determined by determining the step height D so that the condition (1) is equivalent. When designing a contact lens, it is possible to interconvert contact lenses and IOLs having equivalent technical effects. That is, contact lenses and IOLs having equivalent technical effects can be manufactured.

  FIG. 4A to FIG. 4D are diagrams showing the shape and optical performance of the multifocal ophthalmic lens 1 of the first embodiment. FIG. 4A is a diagram showing an annular structure added to the base curve, and shows a cross-sectional structure expressed by subtracting the base curve component from the annular structure forming surface. In FIG. 4A, the vertical axis indicates the shape deviation (shape error, unit: μm) with respect to the base curve, and the horizontal axis indicates the incident light beam radius (pupil height, unit: mm). FIG. 4B is a diagram showing the relationship between the incident light beam radius and the power. In FIG. 4B, the vertical axis indicates the frequency (unit: Dptr), and the horizontal axis indicates the incident light beam radius (pupil height, unit: mm). 4 (c) and 4 (d) show the relationship between the spot intensity and the frequency (unit: Dptr) when the e-line light beam is incident at an incident light beam radius of 2.0 mm and 4.0 mm, respectively. FIG. The frequencies shown in FIG. 4C and FIG. 4D are frequencies given by the annular structure, and are obtained by subtracting the frequencies given by the base curve. 4 (c) and 4 (d), the vertical axis represents the spot intensity, and the horizontal axis represents the frequency (unit: Dptr). As shown in FIGS. 4C and 4D, the multifocal ophthalmic lens 1 of Example 1 has a distance power and a near power of 0 Dptr and 2.5 Dptr, respectively. The frequency L is 2.5 Dptr.

  5 (a) to 5 (d) are diagrams showing the shape and optical performance of the multifocal ophthalmic lens 1 of Example 2, respectively, and are the same as FIGS. 4 (a) to 4 (d). FIG. As shown in FIGS. 5C and 5D, the multifocal ophthalmic lens 1 of Example 2 has a distance power and a near power of 0.0 Dptr and 3.0 Dptr, respectively. The addition power L is 3.0 Dptr.

  6 (a) to 6 (d) are diagrams showing the shape and optical performance of the multifocal ophthalmic lens 1 of Example 3, respectively, and are the same as FIGS. 4 (a) to 4 (d). FIG. As shown in FIGS. 6 (c) and 6 (d), the multifocal ophthalmic lens 1 of Example 3 has a distance power and a near power at the paraxial position of 0.0 Dptr, Although 4.0 Dptr, the addition power L at Φ2.0 is 2.5 Dptr.

  FIGS. 7A to 7D are diagrams showing the shape and optical performance of the multifocal ophthalmic lens 1 of Example 4, respectively, and are the same as FIGS. 4A to 4D. FIG. As shown in FIGS. 7C and 7D, the multifocal ophthalmic lens 1 of Example 4 has a distance diopter and a near diopter of 0.0 Dptr and 2.0 Dptr, respectively. The addition power L is 2.0 Dptr. Since the power given by the base curve is 0.5 Dptr, the distance power and the near power are 0.5 Dptr and 2.5 Dptr in the final shape, respectively.

  FIGS. 8A to 8D are views showing the shape and optical performance of the multifocal ophthalmic lens 1 of Example 5, respectively, and are the same as FIGS. 4A to 4D. FIG. As shown in FIGS. 8C and 8D, the multifocal ophthalmic lens 1 of Example 5 has a distance power and a near power of 20.3 Dptr and 22.3 Dptr, respectively. The addition power L is 2.0 Dptr.

  FIGS. 9A to 9D are diagrams showing the shape and optical performance of the multifocal ophthalmic lens 1 of Example 6, respectively, and are the same as FIGS. 4A to 4D. FIG. As shown in FIG. 9C and FIG. 9D, the multifocal ophthalmic lens 1 of Example 6 has a distance power and a near power of 20.3 Dptr and 23.8 Dptr, respectively. The addition power L is 3.5 Dptr.

  10 (a) to 10 (d) are diagrams showing the shape and optical performance of the multifocal ophthalmic lens 1 of Example 7, respectively, and are the same as FIGS. 4 (a) to 4 (d). FIG. FIG. 10E is a diagram showing the relationship between the incident light beam radius and the additional base power in the multifocal ophthalmic lens 1 of the seventh embodiment. In FIG. 10E, the vertical axis indicates the additional base power (unit: Dptr), and the horizontal axis indicates the incident light beam radius (pupil height, unit: mm). The additional base power shown here is a refractive power added to the base curves in the first to sixth embodiments. As shown in FIG. 10E, in Example 7, a refractive power of 2.5 Dptr is uniformly added over the entire effective beam diameter. Specifically, the multifocal ophthalmic lens 1 of Example 7 has a tighter base curve than the multifocal ophthalmic lens 1 of Examples 1 to 6. In the seventh embodiment, when a base curve having a high refractive power is applied, the 0th-order diffracted light is converged near and the 1st-order diffracted light is condensed far away. Further, since the progressive structure has a progressive structure in which the light collected in the distance changes to the near distance, the utilization efficiency of the diffracted light with respect to the middle from the far distance to the near distance becomes high. As shown in FIGS. 10C and 10D, the multifocal ophthalmic lens 1 of Example 7 has a distance diopter and a near diopter of 0.0 Dptr and 2.5 Dptr, respectively. The addition power L is -2.5 Dptr.

  FIG. 11A to FIG. 11E are diagrams showing the shape and optical performance of the multifocal ophthalmic lens 1 of the eighth embodiment. FIG. 11A is a diagram showing a periodic structure added to the base curve, and shows a cross-sectional structure expressed by subtracting the base curve component from the periodic structure forming surface. In FIG. 11A, the vertical axis represents the shape deviation (shape error, unit: μm) with respect to the base curve, and the horizontal axis represents the incident light beam radius (pupil height, unit: mm). FIG. 11B is a diagram showing the relationship between the incident light beam radius and the power. In FIG. 11B, the vertical axis indicates the frequency (unit: Dptr), and the horizontal axis indicates the incident light beam radius (pupil height, unit: mm). In FIG. 11B, the solid line indicates the power change of the first-order diffracted light, and the broken line indicates the power change of the −1st-order diffracted light. The 0th-order light is constant at an addition power of 0.0 Dptr. FIGS. 11C and 11D are views similar to FIGS. 4C and 4D, respectively. FIG. 11 (e) is the same diagram as FIG. 10 (e). As shown in FIG. 11E, in Example 8, a refractive power of 1.5 Dptr is uniformly added up to an incident light beam radius of 1.0 mm, and thereafter, the added refractive power is reduced and the incident light beam is reduced. It becomes 0 Dptr at a radius of 2.5 mm. As shown in FIGS. 11C and 11D, the multifocal ophthalmic lens 1 of Example 8 has a distance power, an intermediate power, and a near power of −0.95 Dptr, 0, respectively. 0.0 Dptr and 0.95 Dptr, and the addition power L is 1.9 Dptr. Since the power given by the base curve is shown in FIG. 11E, the distance power, the intermediate power, and the near power are 0.0 Dptr, 1.5 Dptr, and 3.0 Dptr in the final shape, respectively.

  12 (a) to 12 (e) are diagrams showing the shape and optical performance of the multifocal ophthalmic lens 1 of Example 9, respectively, and are the same as FIGS. 11 (a) to 11 (e). FIG. As shown in FIGS. 12 (c) and 12 (d), the multifocal ophthalmic lens 1 of Example 9 has a distance power, an intermediate power, and a near power of −0.95 Dptr, 0, respectively. 0.0 Dptr and 0.95 Dptr, and the addition power L is 1.9 Dptr. Since the power given by the base curve is as shown in FIG. 12 (e), the distance power, the intermediate power, and the near power are 0.0 Dptr, 1.5 Dptr, and 3.0 Dptr in the final shape, respectively.

(Comparative Examples 1 and 2)
The multifocal ophthalmic lens of Comparative Example 1 is a type having a blazed diffractive structure, and has the same addition power of 2.5 Dptr as the multifocal ophthalmic lens 1 of Example 1. The multifocal ophthalmic lens of Comparative Example 2 is a type having a periodic structure type diffractive structure. Table 2 shows specific numerical configurations of Comparative Examples 1 and 2.

  13 (a) to 13 (d) are diagrams showing the shape and optical performance of the multifocal ophthalmic lens of Comparative Example 1, respectively, and are the same views as FIGS. 4 (a) to 4 (d). It is. As shown in FIGS. 13 (c) and 13 (d), the multifocal ophthalmic lens of Comparative Example 1 has a distance power and a near power of 0 Dptr and 2.5 Dptr, respectively, and an addition power L Is 2.5 Dptr. FIGS. 14A to 14E are diagrams showing the shape and optical performance of the multifocal ophthalmic lens of Comparative Example 2, respectively, and are the same as FIGS. 11A to 11E. FIG. The multifocal ophthalmic lens of Comparative Example 2 has a distance power, an intermediate power, and a near power of −1.5 Dptr, 0.0 Dptr, and 1.5 Dptr, respectively, and an addition power L of 3.0 Dptr. Since the power given by the base curve is as shown in FIG. 14E, the distance power, the intermediate power, and the near power are 0.0 Dptr, 1.5 Dptr, and 3.0 Dptr in the final shape, respectively.

(Comparison)
The multifocal ophthalmic lens of Comparative Example 1 is designed so that the outer ring zone has a narrower gap between steps. Further, none of the conditions (2) to (4) is satisfied. Therefore, as shown in FIGS. 13B to 13D, there is no frequency change between the near power and the far power (that is, there is no intermediate power). Moreover, since the space | interval of level | step differences becomes narrow as an outer ring zone, the total number of level | steps inevitably increases. As described above, in Comparative Example 1, since the number of steps as a flare generation factor is large, the degradation of imaging performance due to the occurrence of flare is large. The same applies to the multifocal ophthalmic lens of Comparative Example 2. In other words, the multifocal ophthalmic lens of Comparative Example 2 is designed so that the outer period (the unevenness formation interval) is narrower. Therefore, as shown in FIGS. 14B to 14D, there is no frequency change between the near power and the far power, that is, there is no intermediate power. In addition, since the number of steps is large, the degradation of imaging performance due to the occurrence of flare is large.

  On the other hand, the multifocal ophthalmic lenses 1 of Examples 1 to 7 have a configuration in which the outer ring zone has a wider interval between steps. In another aspect, the conditions (2) to (4) are satisfied. As a result, as shown in (b) to (d) of each of FIGS. 4 to 10, there is a region where the intermediate power between the distance power and the near power, that is, the frequency changes, Light incident on the region contributes to the resolution of the intermediate position. Therefore, it is possible to clearly see far, middle and near, and a sufficient depth of field can be obtained. In addition, since the total number of steps is reduced by increasing the interval between steps, the occurrence of flare due to the step structure is effectively suppressed, and the degradation of imaging performance is small. For example, although the multifocal ophthalmic lens 1 of Example 1 has the same addition power as the multifocal ophthalmic lens of Comparative Example 1, the total number of steps is small (Example 1: 9 steps, Comparative Example) 1:14). Moreover, since the light in the portion with the incident light beam radius of 1.5 mm to 2.43 mm contributes to the resolution of the position between the addition powers, a sufficient depth of field is achieved. In addition, in the multifocal ophthalmic lens 1 of Examples 8 and 9, the outer period is wider. Therefore, unlike Comparative Example 2, there is a region where the frequency changes, and light incident on the region contributes to the resolution of the intermediate position. Therefore, it is possible to clearly see far, middle and near, and a sufficient depth of field can be obtained.

  The above is the description of the embodiment of the present invention. The present invention is not limited to the above-described configuration, and various modifications can be made within the scope of the technical idea of the present invention.

1 Multifocal ophthalmic lens 1x Contact lens 1y IOL
Rx1, Ry1 First surface Rx2, Ry2 Second surface

Claims (11)

This is a multifocal ophthalmic lens having an annular structure in which at least one surface is divided into a plurality of concentric refracting surfaces, and a step in a substantially horizontal direction is formed on the optical axis between the adjacent refracting surfaces. And
The ring zone structure is added to the base curve shape,
When the height of the step is defined as D (unit: μm), the refractive index of the multifocal ophthalmic lens at the e-line is defined as n _1, and the refractive index of water at the e-line is defined as n ₀ The following condition (1)
0.190 <| D × (n ₁ −n ₀ ) | <0.370 (1)
While satisfying
Of the two adjacent refracting surfaces, a refracting surface far from the optical axis is defined as an outer refracting surface, and a refracting surface closer to the optical axis is defined as an inner refracting surface. Characterized by having at least one structure having a value between the radius of curvature of the inner refractive surface and the radius of curvature of the base curve shape so that the radius of curvature of the base curve shape approaches the base curve shape. Focal ophthalmic lens. This is a multifocal ophthalmic lens having an annular structure in which at least one surface is divided into a plurality of concentric refracting surfaces, and a step in a substantially horizontal direction is formed on the optical axis between the adjacent refracting surfaces. And
The ring zone structure is added to the base curve shape,
The height of the step D (unit: [mu] m) is defined as, with the refractive index of the multifocal ophthalmic lens in the e-line is defined as n _1, defines the refractive index of water at the e-line and n _0,
The function due to the step of the Fresnel lens shape added to the base curve shape is replaced with a function φ (h) expressed in the form of an optical path length addition amount at a height h (unit: mm) from the optical axis. The fourth-order optical path difference function coefficients are defined as P ₂ and P ₄ , respectively, and the blazed wavelength that gives the optical path length difference for one wavelength when assuming the refractive index at the e-line at the step is λ _B (unit: μm), and a constant term for setting the phase on the optical axis of the annular zone is defined as P ₀ (takes an arbitrary number in the range of −0.5 ≦ P ₀ <0.5),
When ROUND (X, Y) is a function that gives a value obtained by rounding X to the nearest Y decimal place,
φ (h) = (P ₀ + P ₂ · h ² + P ₄ · h ⁴ −ROUND (P ₀ + P ₂ · h ² + P ₄ · h ⁴ , 1)) × λ _B
λ _B = | D × (n ₁ −n ₀ ) |
While satisfying
Next condition (2)
−0.40 <P ₄ / P ₂ <−0.01 (2)
Multifocal ophthalmic lens characterized by satisfying This is a multifocal ophthalmic lens having an annular structure in which at least one surface is divided into a plurality of concentric refracting surfaces, and a step in a substantially horizontal direction is formed on the optical axis between the adjacent refracting surfaces. And
The ring zone structure is given to the base curve shape,
In the annular zone structure, an arrangement interval between a first annular zone step closest to the optical axis and a second annular zone step outside the first annular zone step in a direction perpendicular to the optical axis ( a ₂ −a ₁ ), and an arrangement interval in the direction perpendicular to the optical axis between the outermost final step of the annular structure and the first inner step inside one of the final steps is (a _last −a _last−1 ), and the arrangement interval between the first inner step and the second inner step inside one of the first inner steps in the direction perpendicular to the optical axis is (a _{last- 1} -a _last-2 ), the following conditions (3) and (4)
0.25 <(a _last −a _last−1 ) / (a ₂ −a ₁ ) <2.00 (3)
1.00 <(a _last -a _last-1 ) / (a _last-1 -a _last-2 ) <3.00 (4)
A multifocal ophthalmic lens characterized by satisfying When the radius of curvature of the base curve shape is defined as Rbase (unit: mm) and the radius of curvature of the refractive surface including the optical axis in the annular structure is defined as R1 (unit: mm), the following conditions are satisfied. (5)
| R1-Rbase |> | Ra-Rbase | (5)
A first outer refracting surface having a radius of curvature Ra (unit: mm) satisfying the above condition is outside the refracting surface including the optical axis, and the following condition (6)
| Ra-Rbase |> | Rb-Rbase | (6)
The second outer refracting surface having a radius of curvature Rb (unit: mm) satisfying the above condition is outside the first outer refracting surface. 4. Focal ophthalmic lens.   The second outer refracting surface is an outermost refracting surface of the annular structure, and the first outer refracting surface is adjacent to the inner side of the second outer refracting surface. Item 5. The multifocal ophthalmic lens according to Item 4. When the height of the step is defined as D (unit: μm), the refractive index of the multifocal ophthalmic lens at the e-line is defined as n _1, and the refractive index of water at the e-line is defined as n ₀ The following condition (1)
0.190 <| D × (n ₁ −n ₀ ) | <0.370 (1)
The multifocal ophthalmic lens according to claim 4 or 5 quoting claim 2 or claim 3, wherein:   The outermost final annular zone of the annular zone structure is smoothly connected to a base curve shape located outside the final annular zone, according to any one of claims 1 to 6. The multifocal ophthalmic lens described in 1. A multifocal ophthalmic lens having a concentric periodic structure formed on at least one surface,
The periodic structure is an annular structure in which a plurality of uneven shapes with different periods added to the base curve shape are repeatedly arranged in the radial direction of the multifocal ophthalmic lens,
The difference to Dm (unit: [mu] m) between the minimum thickness and the maximum thickness of the optical axis direction of the periodic structure is defined to be the refractive index of the multifocal ophthalmic lens in the e-line is defined as n _1, the water in the e-line When the refractive index of n is defined as n ₀ , the following condition (7)
0.190 <| Dm × (n ₁ −n ₀ ) | <0.370 (7)
While satisfying
Of the two adjacent cycles, when the cycle far from the optical axis is defined as the outer cycle and the cycle closer to the optical axis is defined as the inner cycle, the outer cycle is greater than the inner cycle. A multifocal ophthalmic lens, characterized by having at least one wide structure. A resin molded product obtained by molding a resin having a refractive index of n ₁
The refractive index n ₁ satisfies the following condition (8)
1.38 <n1 <1.75 (8)
The multifocal ophthalmic lens according to claim 1, wherein the multifocal ophthalmic lens according to claim 1 is satisfied. Add power obtained from the convergence position of the light with the highest diffraction efficiency and the convergence position of the light with the second highest diffraction efficiency when the e-line light beam is incident at an incident light beam diameter of 2.0 mm. When the absolute value of L is defined as L (unit: Dptr), the following condition (9)
1.0 <L <5.0 (9)
The multifocal ophthalmic lens according to claim 1, wherein the multifocal ophthalmic lens according to claim 1 is satisfied. When the pupil height at the connection position between the outermost final annular zone of the annular zone structure and the base curve shape is defined as hmax, the following condition (10)
1.2 <hmax <4.0 (10)
The multifocal ophthalmic lens according to claim 1, wherein the multifocal ophthalmic lens according to claim 1 is satisfied.

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