JP4404317B2

JP4404317B2 - Double-sided aspherical progressive-power lens and design method thereof

Info

Publication number: JP4404317B2
Application number: JP2006236226A
Authority: JP
Inventors: 明木谷; 吉洋菊池; 隆志畑中
Original assignee: Hoya Corp
Current assignee: Hoya Corp
Priority date: 2003-11-27
Filing date: 2006-08-31
Publication date: 2010-01-27
Anticipated expiration: 2024-11-29
Also published as: JP2006350380A

Description

本発明は、例えば、眼鏡用老視用累進屈折力レンズとして用いられるレンズであって、
累進屈折力作用が、物体側表面である第１の屈折表面と眼球側表面である第２の屈折表面とに分割配分されており、且つ、前記第１の表面と前記第２の表面とを合わせて、処方値に基づいた遠用度数（Ｄｆ）と加入度数（ＡＤＤ）とを与える構成となっている両面非球面型累進屈折力レンズおよびその設計方法に関する。 The present invention is, for example, a lens used as a progressive-power lens for presbyopia for glasses,
The progressive power action is divided and divided into a first refractive surface that is an object side surface and a second refractive surface that is an eyeball side surface, and the first surface and the second surface are divided. In addition, the present invention relates to a double-sided aspherical progressive-power lens and a design method thereof, which are configured to give a distance power (Df) and an addition power (ADD) based on a prescription value.

累進屈折力レンズは、老視用眼鏡レンズでありながら外見上は容易に老眼鏡と察知されない利点や、遠距離から近距離まで切れ目なく連続的に明視しうる利点などにより、一般に広く利用されている。しかしながら、限られたレンズ面積の中に境界線を介入させることなく、遠方を見るための視野、近方を見るための視野、それらの中間的な距離を見るための視野といった複数の視野を配置する都合から、各々の視野の広さが必ずしも充分ではない。さらに、主として側方の視野に、像の歪みや揺れを感じさせる領域が存在するなど、累進屈折力レンズ特有の欠点があることも広く知られている。 Progressive-power lenses are widely used because they are presbyopic eyeglass lenses that are not easily perceived as presbyopia in appearance, and that they can be clearly visible continuously from long to short distances. Yes. However, multiple fields of view, such as a field of view for viewing a distance, a field of view for viewing a near distance, and a field of view for viewing an intermediate distance between them, are arranged without a boundary line in a limited lens area. Therefore, the width of each field of view is not always sufficient. Further, it is widely known that there are defects inherent to the progressive-power lens, such as a region in which the image is distorted or shaken mainly in the lateral visual field.

これらの累進屈折力レンズ特有の欠点を改善する目的で古くから様々な提案がなされてきたが、それら従来の累進屈折力レンズの面構成は、物体側表面に「累進面」を配し、眼球側表面に「球面」や「乱視面」を配した組合せのものが殆どであった。また、これらとは逆に、眼球側表面に「累進作用」を付加させたことを特徴とする累進屈折力レンズとして、１９７０年に仏国ＥｓｓｅｌＯｐｔｉｃａｌＣｏ．（現Ｅｓｓｉｌｏｒ）から発売されたＡｔｏｒａｌＶａｒｉｐｌａｓがある。 Various proposals have been made for a long time with the aim of improving the disadvantages inherent to these progressive-power lenses, but the surface configuration of these conventional progressive-power lenses has a “progressive surface” on the object-side surface, and an eyeball. Most of the combinations had a “spherical surface” or “astigmatic surface” on the side surface. On the contrary, as a progressive addition lens characterized by adding a “progressive action” to the eyeball side surface, in 1970, Essel Optical Co. There is an Atoral Variplace sold by (currently Essilor).

また、近年提案された先行技術として、例えば、特許文献１、２に記載の技術等などがあり、一般には、裏面累進（または凹面累進）と呼ばれている。この特許文献１にて提案された裏面累進における面構成の主な目的は、必要な加入度数の一部または全部を、物体側表面から眼球側表面に分担させることで、遠用部と近用部の像の倍率差を減らし、像の歪みや揺れを改善しようとするものである。 Moreover, as a prior art proposed in recent years, for example, there are techniques described in Patent Documents 1 and 2 and the like, which are generally called back surface progression (or concave surface progression). The main purpose of the surface configuration in the back surface progression proposed in Patent Document 1 is to share a part or all of the required addition power from the object side surface to the eyeball side surface, so that the distance portion and the near portion are used. This is to reduce the magnification difference of the image of the part and to improve the distortion and shaking of the image.

即ち、特許文献１は、物体側表面を球面や回転対称非球面とすることで「累進作用」を全て消し去り、眼球側表面のみに所定の加入度数を与える「累進面」を付加（融合）させている。また、特許文献２は、物体側表面の「累進面」における加入度数を所定の値より少なくし、不足分の加入度数を与える「累進面」を裏面側の「球面」や「乱視面」に付加（融合）させることを提案している。 That is, Patent Document 1 adds (progress) a “progressive surface” that gives a predetermined addition power only to the eyeball-side surface by eliminating all “progressive action” by making the object-side surface spherical or rotationally symmetric aspherical. I am letting. Further, Patent Document 2 discloses that a “progressive surface” that gives a shortage of addition power to a “progressive surface” on the object side surface is less than a predetermined value and is used as a “spherical surface” or “astigmatic surface” on the back surface side. It is proposed to add (fuse).

また、目的や根拠に違いがあるが、眼球側表面に「累進作用」を付加させた構成を有する累進屈折力レンズの他の先行技術として、例えば、特許文献３、特許文献４、特許文献５、特許文献６等があり、更に、特許文献２に記載のものと同様に、レンズの両面に「累進作用」を持たせた先行技術として、例えば、特許文献７や特許文献８がある。そして、これらの先行技術の共通点は、必要な加入度数をレンズの物体側、眼球側の２面で分担して与えていることである。 Further, although there are differences in purpose and grounds, as other prior arts of progressive power lenses having a configuration in which a “progressive action” is added to the eyeball side surface, for example, Patent Document 3, Patent Document 4, and Patent Document 5 Patent Document 6 and the like. Further, as in the case of Patent Document 2, there are Patent Document 7 and Patent Document 8, for example, as prior arts in which “progressive action” is given to both surfaces of the lens. The common point of these prior arts is that the required addition power is shared by the two surfaces on the object side and the eyeball side of the lens.

ＷＯ９７／１９３８２号公報WO97 / 19382 gazette ＷＯ９７／１９３８３号公報WO97 / 19383 publication 特公昭４７−２３９４３号公報Japanese Patent Publication No. 47-23943 特開昭５７−１０１１２号公報JP-A-57-10112 特開平１０−２０６８０５号公報Japanese Patent Laid-Open No. 10-206805 特開２００１−２１８４６号公報Japanese Patent Laid-Open No. 2001-21846 特開２０００−３３８４５２号公報JP 2000-338452 A 特開平６−１１８３５３号公報JP-A-6-118353

上述した先行技術の主な目的は、累進屈折力レンズに必要な加入度数の一部または全部を、レンズの物体側表面から眼球側表面に分担させることで、当該レンズにおける遠用部と近用部の倍率差を減らし、倍率差による像の歪みや揺れを改善しようとするものである。ところが、それらの改善効果が得られる根拠については明確な記載が少なく、わずかに特許文献２（以下、従来技術１と記載する−場合もある。）等において、部分的な記載があるにすぎない。即ち、特許文献２には次のような（１）式〜（３）式に示すレンズ倍率（ＳＭ）の計算式が開示され、レンズ設計の基本評価パラメータとして採用されている。 The main purpose of the above-described prior art is to share a part or all of the addition power necessary for the progressive power lens from the object side surface of the lens to the eyeball side surface, so that the distance portion and the near purpose in the lens are used. It is intended to reduce the magnification difference of the part and improve the distortion and shaking of the image due to the magnification difference. However, there is little clear description about the grounds for obtaining such improvement effects, and there is only a partial description in Patent Document 2 (hereinafter, sometimes referred to as the prior art 1). . That is, Patent Document 2 discloses a calculation formula for lens magnification (SM) shown in the following formulas (1) to (3), which is adopted as a basic evaluation parameter for lens design.

ここで、特許文献２の記載を引用する。
「レンズの倍率ＳＭは、一般的に次の式で表される。
ＳＭ＝Ｍｐ×Ｍｓ…（１）
ここで、Ｍｐはパワーファクター、また、Ｍｓはシェープファクターと呼ばれる。レンズの眼球側の面の頂点（内側頂点）から眼球までの距離を頂間距離Ｌ、内側頂点の屈折力（内側頂点屈折力）をＰｏ、レンズの中心の厚みをｔ、レンズの屈折率をｎ、レンズの物体側の面のベースカーブ（屈折力）をＰｂとすると以下のように表される。
Ｍｐ＝１／（１−Ｌ×Ｐｏ）…（２）
Ｍｓ＝１／（１−（ｔ×Ｐｂ）／ｎ）…（３）
なお、式（２）および（３）の計算にあたっては、内側頂点屈折力Ｐｏ及びベースカーブＰｂについてはディオプトリ（Ｄ）を、また、距離Ｌおよび厚みをｔについてはメートル（ｍ）をそれぞれ用いる。」 Here, the description of Patent Document 2 is cited.
“The lens magnification SM is generally expressed by the following equation.
SM = Mp × Ms (1)
Here, Mp is called a power factor, and Ms is called a shape factor. The distance from the vertex of the lens on the eyeball side (inner vertex) to the eyeball is the apex distance L, the refractive power of the inner vertex (inner vertex refractive power) is Po, the thickness of the center of the lens is t, and the refractive index of the lens is When the base curve (refractive power) of the object side surface of the lens is Pb, it is expressed as follows.
Mp = 1 / (1-L × Po) (2)
Ms = 1 / (1− (t × Pb) / n) (3)
In calculating the equations (2) and (3), diopter (D) is used for the inner vertex power Po and the base curve Pb, and the meter (m) is used for the distance L and the thickness t. "

そして、特許文献２は、これらのレンズ倍率（ＳＭ）の計算式を用いて遠用部と近用部の倍率の差を算出し、その倍率差が少ないので、像の歪みや揺れが改善されているとしている。 Patent Document 2 calculates the difference in magnification between the distance portion and the near portion using these lens magnification (SM) formulas, and since the difference in magnification is small, image distortion and shaking are improved. It is going to be.

本願発明者の研究によれば、上記従来技術１は、その他の先行技術に比較して一定の効果が認められるが、より高性能のレンズ設計を行なうためには、さらに以下の点を検討する必要のあることが判明した。
ａ．上記従来技術１で用いている基本評価パラメータには、本来ならばレンズの中央近傍に対してのみ適用されるべきパラメータが含まれている。このことは、「レンズの眼球側の面の頂点から眼球までの距離Ｌ」と「レンズの中心の厚みｔ」という記載からも明らかである。即ち、特許文献２の実施例では、レンズの中央近傍にある遠用部に対してのみ適用されるべき基本評価パラメータが、レンズ中心から大きく下方に位置する近用部に対しても適用されていることになるので、それによる誤差発生の可能性が残る。 According to the research of the present inventor, the conventional technique 1 has a certain effect as compared with other prior arts. However, in order to design a lens with higher performance, the following points are further examined. It turned out to be necessary.
a. The basic evaluation parameters used in the prior art 1 include parameters that should be applied only to the vicinity of the center of the lens. This is also clear from the descriptions “the distance L from the apex of the lens on the eyeball side to the eyeball” and “the lens center thickness t”. In other words, in the example of Patent Document 2, the basic evaluation parameter that should be applied only to the distance portion near the center of the lens is also applied to the near portion located substantially below the lens center. Therefore, there is a possibility that an error occurs due to this.

ｂ．従来技術１では、上記のＬ、ｔ、Ｐｏ、Ｐｂの他に「レンズの屈折率ｎ」を加えた、５個の基本評価パラメータでレンズの倍率ＳＭが算出されている。しかしながら、実際に度数の付いたレンズを前後に傾けてみればすぐわかるように、像の大きさは、「視線とレンズ面との角度」に強く影響されると考えられる。従って、特にレンズ中心から大きく下方に位置する近用部の倍率の算出では、この「視線とレンズ面との角度」を無視出来ないと考えられる。よって、従来技術１のレンズ設計には「視線とレンズ面との角度」を考慮することなく
レンズの倍率を算出していることによる誤差発生の可能性を有する。 b. In the prior art 1, the lens magnification SM is calculated using five basic evaluation parameters obtained by adding “lens refractive index n” in addition to the above L, t, Po, and Pb. However, it is considered that the size of the image is strongly influenced by the “angle between the line of sight and the lens surface”, as can be readily understood by tilting the lens with the power actually back and forth. Therefore, it can be considered that this “angle between the line of sight and the lens surface” cannot be ignored particularly in the calculation of the magnification of the near portion located greatly below the lens center. Therefore, the lens design of the prior art 1 has a possibility of generating an error due to the calculation of the lens magnification without considering the “angle between the line of sight and the lens surface”.

ｃ．従来技術１における「倍率」には、乱視レンズへの応用例の記載以外に方向の概念がない。この概念がないため、例えば、レンズ中心から大きく下方に位置する近用部においては、「縦方向と横方向との倍率が異なる」という場合があり、これによる誤差発生の可能性が生ずる。 c. The “magnification” in the prior art 1 has no concept of direction other than the description of an application example to an astigmatic lens. Since this concept does not exist, for example, in the near portion located greatly below the lens center, there may be a case where “the magnification in the vertical direction is different from that in the horizontal direction”, which may cause an error.

ｄ．近用部に対する倍率計算を正確に行うには、視標までの距離、即ち「対物距離」が計算ファクターとして追加されねばならない。しかし、従来技術１ではこの「対物距離」について考慮されていない。このため、当該考慮がないことに起因する誤差の可能性も否定できない。 d. In order to accurately calculate the magnification for the near portion, the distance to the target, that is, the “object distance” must be added as a calculation factor. However, the “objective distance” is not considered in the prior art 1. For this reason, the possibility of the error resulting from the absence of such consideration cannot be denied.

ｅ．従来技術１では、倍率計算においてプリズム作用による影響が考慮されていない。このため、当該考慮がないことに起因する誤差の可能性もある。 e. In prior art 1, the influence of the prism action is not taken into account in the magnification calculation. For this reason, there is a possibility of an error due to the absence of such consideration.

このように、従来技術１は、「倍率」の算出をより正確に行うという観点からみると、必ずしも満足できるものではない。 As described above, the prior art 1 is not always satisfactory from the viewpoint of calculating the “magnification” more accurately.

本発明は、かかる課題を解決するためになされたものであり、上述した、「視線とレンズ面との角度」や「対物距離」による影響を考慮し、レンズにおける遠用部と近用部とにおける像の倍率差を低減し、処方値に対する良好な視力補正と、装用時における歪みの少ない広範囲な有効視野を与える両面非球面型累進屈折力レンズと、その設計方法を提供することを目的とする。 The present invention has been made to solve such a problem, and in consideration of the influence of the above-mentioned “angle between the line of sight and the lens surface” and “objective distance”, the distance portion and the near portion in the lens The objective is to provide a double-sided aspherical progressive-power lens that reduces the difference in image magnification, provides a good visual acuity correction for prescription values, and provides a wide effective field of view with little distortion during wearing, and a design method thereof. To do.

上述の課題を解決するため、本発明は以下の構成を有している。 In order to solve the above-described problems, the present invention has the following configuration.

（第１の構成）
物体側表面である第１の屈折表面と、眼球側表面である第２の屈折表面とに分割配分されている累進屈折力作用を備えた両面非球面型累進屈折力レンズであって、
前記第１の屈折表面において、遠用度数測定位置Ｆ１における横方向の表面屈折力及び縦方向の表面屈折力をそれぞれ、ＤＨｆ、ＤＶｆとし、
前記第１の屈折表面において、近用度数測定位置Ｎ１における横方向の表面屈折力及び縦方向の表面屈折力をそれぞれＤＨｎ、ＤＶｎとするとき、
ＤＨｆ＋ＤＨｎ＜ＤＶｆ＋ＤＶｎ、かつ、ＤＨｎ＜ＤＶｎ
となる関係式を満足させると共に、前記第１の屈折表面のＦ１及びＮ１における表面非点収差成分を、前記第２の屈折表面にて相殺し、前記第１と第２の屈折表面とを合わせて処方値に基づいた遠用度数（Ｄｆ）と加入度数（ＡＤＤ）とを与えるようにし、
前記第１の屈折表面の非点収差の分布が、前記遠用度数測定位置Ｆ１を通る一本の子午線を境に左右対称であり、前記第２の屈折表面の非点収差の分布が、この第２の屈折表面の遠用度数測定位置Ｆ２を通る一本の子午線を境に左右非対称であり、かつ、この第２の屈折表面の近用度数測定位置Ｎ２の配置は、所定の距離だけ鼻側に内寄せされていることを特徴とする両面非球面型累進屈折力レンズ。
この構成によれば、眼球側表面における横方向累進作用の分担比率を高くすることにより、水平方向に視野が広がるとともに、物体側表面における縦方向累進作用の分担比率を高くすることにより、遠近の視線移動がしやすく、非点収差の少ない広い両眼視野を有し、装用時にゆれ、歪みの少ない累進屈折力レンズを提供できる。
（第２の構成）
第１の構成にかかる両面非球面型累進屈折力レンズ屈折力レンズにおいて、
前記両面非球面型累進屈折力レンズの近用部における透過非点収差の分布は、鼻側が密、こめかみ側が疎になるように配置されていることを特徴とする両面非球面型累進屈折力レンズ。
この構成によれば、第１の構成の効果に加え、特に近用部から側方にかけての透過非点収差が左右眼で近似するようになり、より良好な両眼視が可能となる。
（第３構成）
物体側表面である第１の屈折表面と、眼球側表面である第２の屈折表面とに分割配分されている累進屈折力作用を備えた両面非球面型累進屈折力レンズの設計方法であって、
前記第１の屈折表面において、遠用度数測定位置Ｆ１における横方向の表面屈折力及び縦方向の表面屈折力をそれぞれ、ＤＨｆ、ＤＶｆとし、
前記第１の屈折表面において、近用度数測定位置Ｎ１における横方向の表面屈折力及び縦方向の表面屈折力をそれぞれＤＨｎ、ＤＶｎとするとき、
ＤＨｆ＋ＤＨｎ＜ＤＶｆ＋ＤＶｎ、かつ、ＤＨｎ＜ＤＶｎ
となる関係式を満足させると共に、前記第１の屈折表面のＦ１及びＮ１における表面非点収差成分を、前記第２の屈折表面にて相殺し、前記第１と第２の屈折表面とを合わせて処方値に基づいた遠用度数（Ｄｆ）と加入度数（ＡＤＤ）とを与えるようにし、
前記第１の屈折表面の非点収差の分布が、前記遠用度数測定位置Ｆ１を通る一本の子午線を境に左右対称であり、前記第２の屈折表面の非点収差の分布が、この第２の屈折表面の遠用度数測定位置Ｆ２を通る一本の子午線を境に左右非対称であり、かつ、この第２の屈折表面の近用度数測定位置Ｎ２の配置は、所定の距離だけ鼻側に内寄せされていることを特徴とする両面非球面型累進屈折力レンズの設計方法。
この構成によれば、眼球側表面における横方向累進作用の分担比率を高くすることにより、水平方向に視野が広がるとともに、物体側表面における縦方向累進作用の分担比率を高くすることにより、遠近の視線移動がしやすく、非点収差の少ない広い両眼視野を有し、装用時にゆれ、歪みの少ない累進屈折力レンズが得られる設計方法を提供できる。
（第４の構成）
第３の構成にかかる両面非球面型累進屈折力レンズの設計方法において、
前記両面非球面型累進屈折力レンズの近用部における透過非点収差の分布は、鼻側が密、こめかみ側が疎になるように配置されていることを特徴とする両面非球面型累進屈折力レンズの設計方法。
この構成によれば、第３の構成の効果に加え、特に近用部から側方にかけての透過非点収差が左右眼で近似するようになり、より良好な両眼視が可能となる。
（第５の構成）
物体側表面である第１の屈折表面と、眼球側表面である第２の屈折表面とに分割配分されている累進屈折力作用を備えた両面非球面型累進屈折力レンズであって、
前記第１の屈折表面において、遠用度数測定位置Ｆ１における横方向の表面屈折力及び縦方向の表面屈折力をそれぞれ、ＤＨｆ、ＤＶｆとし、
前記第１の屈折表面において、近用度数測定位置Ｎ１における横方向の表面屈折力及び縦方向の表面屈折力をそれぞれＤＨｎ、ＤＶｎとするとき、
ＤＨｆ＋ＤＨｎ＜ＤＶｆ＋ＤＶｎ、かつ、ＤＨｎ＜ＤＶｎ
となる関係式を満足させると共に、前記第１の屈折表面のＦ１及びＮ１における表面非点収差成分を、前記第２の屈折表面にて相殺し、前記第１と第２の屈折表面とを合わせて処方値に基づいた遠用度数（Ｄｆ）と加入度数（ＡＤＤ）とを与えるようにし、
前記第１の屈折表面の平均度数の分布が、前記遠用度数測定位置Ｆ１を通る一本の子午線を境に左右対称とし、前記第２の屈折表面の平均度数の分布が、この第２の屈折表面の遠用度数測定位置Ｆ２を通る一本の子午線を境に左右非対称とし、かつ、この第２の屈折表面の近用度数測定位置Ｎ２の配置は、所定の距離だけ鼻側に内寄せされていることを特徴とする両面非球面型累進屈折力レンズ。
この構成によれば、眼球側表面における横方向累進作用の分担比率を高くすることにより、水平方向に視野が広がるとともに、物体側表面における縦方向累進作用の分担比率を高くすることにより、遠近の視線移動がしやすく、適切な平均度数の広い両眼視野を有し、装用時にゆれ、歪み、ぼけの少ない累進屈折力レンズを提供できる。
（第６の構成）
第５の構成にかかる両面非球面型累進屈折力レンズにおいて、
前記両面非球面型累進屈折力レンズの近用部における透過平均度数の分布を、鼻側が密、こめかみ側が疎になるように配置することを特徴とする両面非球面型累進屈折力レンズ。
この構成によれば、第５の構成の効果に加え、特に近用部から側方にかけての透過平均度数が左右眼で近似するようになり、より良好な両眼視が可能となる。
（第７の構成）
物体側表面である第１の屈折表面と、眼球側表面である第２の屈折表面とに分割配分されている累進屈折力作用を備えた両面非球面型累進屈折力レンズの設計方法であって、
前記第１の屈折表面において、遠用度数測定位置Ｆ１における横方向の表面屈折力及び縦方向の表面屈折力をそれぞれ、ＤＨｆ、ＤＶｆとし、
前記第１の屈折表面において、近用度数測定位置Ｎ１における横方向の表面屈折力及び縦方向の表面屈折力をそれぞれＤＨｎ、ＤＶｎとするとき、
ＤＨｆ＋ＤＨｎ＜ＤＶｆ＋ＤＶｎ、かつ、ＤＨｎ＜ＤＶｎ
となる関係式を満足させると共に、前記第１の屈折表面のＦ１及びＮ１における表面非点収差成分を、前記第２の屈折表面にて相殺し、前記第１と第２の屈折表面とを合わせて処方値に基づいた遠用度数（Ｄｆ）と加入度数（ＡＤＤ）とを与えるようにし、
前記第１の屈折表面の平均度数の分布が、前記遠用度数測定位置Ｆ１を通る一本の子午線を境に左右対称とし、前記第２の屈折表面の平均度数の分布が、この第２の屈折表面の遠用度数測定位置Ｆ２を通る一本の子午線を境に左右非対称とし、かつ、この第２の屈折表面の近用度数測定位置Ｎ２の配置は、所定の距離だけ鼻側に内寄せされていることを特徴とする両面非球面型累進屈折力レンズの設計方法。
この構成によれば、眼球側表面における横方向累進作用の分担比率を高くすることにより、水平方向に視野が広がるとともに、物体側表面における縦方向累進作用の分担比率を高くすることにより、遠近の視線移動がしやすく、適切な平均度数の広い両眼視野を有し、装用時にゆれ、歪み、ぼけの少ない累進屈折力レンズが得られる設計方法を提供できる。
（第８の構成）
第７の構成にかかる両面非球面型累進屈折力レンズの設計方法において、
前記両面非球面型累進屈折力レンズの近用部における透過平均度数の分布を、鼻側が密、こめかみ側が疎になるように配置することを特徴とする両面非球面型累進屈折力レンズの設計方法。
この構成によれば、第７の構成の効果に加え、特に近用部から側方にかけての透過平均度数が左右眼で近似するようになり、より良好な両眼視が可能となる。
（第９の構成）
物体側表面である第1の屈折表面と、眼球側表面である第２の屈折表面とに、分割配分されている累進屈折力作用を備えた両面非球面型累進屈折力レンズであって、
前記第1の屈折表面において、近用度数測定位置Ｎ1における横方向の表面屈折力及び縦方向の表面屈折力をそれぞれＤＨｎ、ＤＶｎとするとき、
ＤＶｎ−ＤＨｎ＞ＡＤＤ／２
となる関係式を満足させると共に、前記第1の屈折表面のＮ１における表面非点収差成分を前記第２の屈折表面にて相殺し、前記第1と第２の屈折表面とを合わせて、処方値に基づいた近用度数（Ｄｎ）を与える構成となっていることを特徴とする両面非球面型累進屈折力レンズ。
この構成によれば、特に、近用部において、眼球側表面における横方向累進作用の分担比率を高くすることにより、水平方向に視野が広がり、同時に、物体側表面における縦方向累進作用の分担比率が高まることになるので、遠近の視線移動がしやすく、装用時にゆれ、歪みの少ない累進屈折力レンズを提供できる。
（第１０の構成）
第９の構成かかる両面非球面型累進屈折力レンズにおいて、
前記第1の屈折表面において、遠用度数測定位置Ｆ1における横方向の表面屈折力及び縦方向の表面屈折力をそれぞれＤＨｆ、ＤＶｆとするとき、
ＤＨｆ＋ＤＨｎ＜ＤＶｆ＋ＤＶｎ、かつ、ＤＶｎ−ＤＶｆ＞ＡＤＤ／２、かつ、
ＤＨｎ−ＤＨｆ＜ＡＤＤ／２
となる関係式を満足させると共に、前記第1の屈折表面のＦ1及びＮ１における表面非点収差成分を前記第２の屈折表面にて相殺し、前記第1と第２の屈折表面とを合わせて処方値に基づいた遠用度数（Ｄｆ）と加入度数（ＡＤＤ）を与える構成となっていることを特徴とする両面非球面型累進屈折力レンズ。
この構成によれば、第９の構成の効果に加え、遠用部およびレンズ面全体においてもゆれや歪みの抑制された累進屈折力レンズを提供できる。
（第１１の構成）
第９又は第１０の構成にかかる両面非球面型累進屈折力レンズにおいて、
前記第１の屈折表面が、前記遠用度数測定位置Ｆ１を通る一本の子午線を境に左右対称であり、前記第２の屈折表面が、この第２の屈折表面の遠用度数測定位置Ｆ２を通る一本の子午線を境に左右非対称であって、かつ、この第２の屈折表面の近用度数測定位置Ｎ２の配置は、所定の距離だけ鼻側に内寄せされていることを特徴とする両面非球面型累進屈折力レンズ。
この構成によれば、第９又は第１０の構成の効果に加え、特に遠用部から近用部において視線を移動させるとき、より広い両眼視野を与えることができる。
（第１２の構成）
第９〜第１１のいずれかにかかる両面非球面型累進屈折力レンズにおいて、
前記第１の屈折表面が、前記遠用度数測定位置Ｆ１を通る一本の子午線を母線とした回転面であり、前記第２の屈折表面が、この第２の屈折表面の遠用度数測定位置Ｆ２を通る一本の子午線を境に左右非対称であって、かつ、この第２の屈折表面の近用度数測定位置Ｎ２の配置は、所定の距離だけ鼻側に内寄せされていることを特徴とする両面非球面型累進屈折力レンズ。
この構成によれば、第９〜１１のいずれかの構成の効果に加え、物体側表面に、像のゆれの原因となる面のねじれを存在させないようにすることができる。また、遠用部から近用部において視線を移動させるとき、より広い両眼視野を与えることができる。
（第１３の構成）
第９〜第１１のいずれかに記載の両面非球面型累進屈折力レンズにおいて、
前記第１の屈折表面において、前記遠用度数測定位置Ｆ１を通る水平方向断面曲線は、真円ではなく所定の屈折力変化を有しており、かつ、この水平方向断面曲線上の任意の位置における法線を含む垂直方向断面による断面曲線は、前記遠用度数測定位置Ｆ１を通る子午線と実質的に同一であることを特徴とする両面非球面型累進屈折力レンズ。
この構成によれば、第９〜第１１のいずれかの構成の効果に加え、上記構成を採用することにより、左右側方のゆがみを緩和させ、側方視野を改良することができる。
（第１４の構成）
第９〜第１３のいずれかに記載の両面非球面型累進屈折力レンズにおいて、
前記第1と第２の屈折表面とを合わせて処方値に基づいた遠用度数（Ｄｆ）と加入度数（ＡＤＤ）とを与えると共に、必要に応じてプリズム屈折力（Ｐｆ）を与える構成とする上で、装用状態における視線とレンズ面とが直交しえないことに起因する非点収差や度数誤差の発生、及び周辺視野における像の歪みの発生の少なくとも１種以上の項目について非球面補正したことを特徴とする両面非球面型累進屈折力レンズ。
この構成によれば、第９〜第１３のいずれかの構成の効果に加え、上記の非球面補正により、透過非点収差や透過度数誤差、及び周辺視野における像の歪みの発生等を抑制した累進屈折力レンズを提供できる。
（第１５の構成）
物体側表面である第1の屈折表面と、眼球側表面である第２の屈折表面とに、分割配分されている累進屈折力作用を備えた両面非球面型累進屈折力レンズの設計方法であって、
前記第1の屈折表面において、近用度数測定位置Ｎ1における横方向の表面屈折力及び縦方向の表面屈折力をそれぞれＤＨｎ、ＤＶｎとするとき、
ＤＶｎ−ＤＨｎ＞ＡＤＤ／２
となる関係式を満足させると共に、前記第1の屈折表面のＮ１における表面非点収差成分を前記第２の屈折表面にて相殺し、前記第1と第２の屈折表面とを合わせて、処方値に基づいた近用度数（Ｄｎ）とすることを特徴とする両面非球面型累進屈折力レンズの設計方法。
この構成によれば、特に、近用部において、眼球側表面における横方向累進作用の分担比率を高くすることにより、水平方向に視野が広がり、同時に、物体側表面における縦方向累進作用の分担比率が高まることになるので、遠近の視線移動がしやすく、装用時にゆれ、歪みの少ない累進屈折力レンズが得られる設計方法を提供できる。
（第１６の構成）
第１５の構成にかかる両面非球面型累進屈折力レンズの設計方法において、
前記第1の屈折表面において、遠用度数測定位置Ｆ1における横方向の表面屈折力及び縦方向の表面屈折力をそれぞれＤＨｆ、ＤＶｆとするとき、
ＤＨｆ＋ＤＨｎ＜ＤＶｆ＋ＤＶｎ、かつ、ＤＶｎ−ＤＶｆ＞ＡＤＤ／２、かつ、
ＤＨｎ−ＤＨｆ＜ＡＤＤ／２
となる関係式を満足させると共に、前記第1の屈折表面のＦ1及びＮ１における表面非点収差成分を前記第２の屈折表面にて相殺し、前記第1と第２の屈折表面とを合わせて処方値に基づいた遠用度数（Ｄｆ）と加入度数（ＡＤＤ）を与えることを特徴とする両面非球面型累進屈折力レンズの設計方法。
この構成によれば、第１５の構成の効果に加え、遠用部およびレンズ面全体においてもゆれや歪みの抑制された累進屈折力レンズが得られる設計方法を提供できる。
（第１７の構成）
第１５又は１６にかかる両面非球面型累進屈折力レンズの設計方法において、
前記第１の屈折表面が、前記遠用度数測定位置Ｆ１を通る一本の子午線を境に左右対称であり、前記第２の屈折表面が、この第２の屈折表面の遠用度数測定位置Ｆ２を通る一本の子午線を境に左右非対称であって、かつ、この第２の屈折表面の近用度数測定位置Ｎ２の配置は、所定の距離だけ鼻側に内寄せされていることを特徴とする両面非球面型累進屈折力レンズの設計方法。
この構成によれば、第１５又は第１６の構成の効果に加え、特に遠用部から近用部において視線を移動させるとき、より広い両眼視野を与えることができる。
（第１８の構成）
第１５〜第１７のいずれかにかかる両面非球面型累進屈折力レンズ設計方法において、
前記第１の屈折表面が、前記遠用度数測定位置Ｆ１を通る一本の子午線を母線とした回転面であり、前記第２の屈折表面が、この第２の屈折表面の遠用度数測定位置Ｆ２を通る一本の子午線を境に左右非対称であって、かつ、この第２の屈折表面の近用度数測定位置Ｎ２の配置は、所定の距離だけ鼻側に内寄せされていることを特徴とする両面非球面型累進屈折力レンズ設計方法。
この構成によれば、第１５〜１７のいずれかの構成の効果に加え、物体側表面に、像のゆれの原因となる面のねじれを存在させないようにすることができる。また、遠用部から近用部において視線を移動させるとき、より広い両眼視野を与えることができる。
（第１９の構成）
第１５〜第１７のいずれかにかかる両面非球面型累進屈折力レンズの設計方法において、
前記第１の屈折表面において、前記遠用度数測定位置Ｆ１を通る水平方向断面曲線を、真円ではなく所定の屈折力変化を有するものとし、かつ、この水平方向断面曲線上の任意の位置における法線を含む垂直方向断面による断面曲線は、前記遠用度数測定位置Ｆ１を通る子午線と実質的に同一とすることを特徴とする両面非球面型累進屈折力レンズの設計方法。
この構成によれば、第１５〜第１７のいずれかの構成の効果に加え、上記構成を採用することにより、左右側方のゆがみを緩和させ、側方視野を改良することができる。
（第２０の構成）
第１５〜第１９のいずれかにかかる両面非球面型累進屈折力レンズの設計方法において、
前記第1と第２の屈折表面とを合わせて処方値に基づいた遠用度数（Ｄｆ）と加入度数（ＡＤＤ）とを与えると共に、必要に応じてプリズム屈折力（Ｐｆ）を与える構成とする上で、装用状態における視線とレンズ面とが直交しえないことに起因する非点収差や度数誤差の発生、及び周辺視野における像の歪みの発生の少なくとも１種以上の項目について非球面補正したことを特徴とする両面非球面型累進屈折力レンズの設計方法。
この構成によれば、第１５〜第１９のいずれかの構成の効果に加え、上記の非球面補正により、透過非点収差や透過度数誤差、及び周辺視野における像の歪みの発生等を抑制した累進屈折力レンズが得られる設計方法を提供できる。
（第２１の構成）
物体側表面である第１の屈折表面と、眼球側表面である第２の屈折表面とに分割配分されている累進屈折力作用を備えた両面非球面型累進屈折力レンズであって、
前記第１の屈折表面において、遠用度数測定位置Ｆ１における横方向の表面屈折力及び縦方向の表面屈折力をそれぞれ、ＤＨｆ、ＤＶｆとし、
前記第１の屈折表面において、近用度数測定位置Ｎ１における横方向の表面屈折力及び縦方向の表面屈折力をそれぞれＤＨｎ、ＤＶｎとするとき、
ＤＶｎ−ＤＶｆ＞ＡＤＤ／２
となる関係式を満足させると共に、前記第１の屈折表面のＦ１及びＮ１における表面非点収差成分を、前記第２の屈折表面にて相殺し、前記第１と第２の屈折表面とを合わせて処方値に基づいた加入度数（ＡＤＤ）を与えるようにし、
かつ、
Ｆ１を通る縦方向断面曲線において、Ｆ１からＮ１と同じ高さに至る縦方向断面度数変化の５０％を与える位置を中心として縦方向へ±４ｍｍに位置する２本の水平線と、Ｆ１を通る縦方向の直線から水平方向へ±１５ｍｍに位置する２本の縦線で囲まれた矩形内の任意の位置において、
前記第１の屈折表面における表面縦方向断面度数の微分値は、横方向微分値の絶対値よりも縦方向微分値の絶対値の方が大きいことを特徴とする両面非球面型累進屈折力レンズ。
この構成によれば、特に、累進屈折力レンズの使用頻度の高い中央の領域で、物体側表面における縦方向累進作用の分担比率を高めることにより、物体側表面の面のねじれを減少させ、像のゆれや歪みを抑制することができる。
（第２２の構成）
物体側表面である第１の屈折表面と、眼球側表面である第２の屈折表面とに分割配分されている累進屈折力作用を備えた両面非球面型累進屈折力レンズであって、
前記第１の屈折表面において、遠用度数測定位置Ｆ１における横方向の表面屈折力及び縦方向の表面屈折力をそれぞれ、ＤＨｆ、ＤＶｆとし、
前記第１の屈折表面において、近用度数測定位置Ｎ１における横方向の表面屈折力及び縦方向の表面屈折力をそれぞれＤＨｎ、ＤＶｎとするとき、
ＤＶｎ−ＤＶｆ＞ＡＤＤ／２
となる関係式を満足させると共に、前記第１の屈折表面のＦ１及びＮ１における表面非点収差成分を、前記第２の屈折表面にて相殺し、前記第１と第２の屈折表面とを合わせて処方値に基づいた加入度数（ＡＤＤ）を与えるようにし、
かつ、
Ｆ１を通る縦方向断面曲線において、Ｆ１からＮ１と同じ高さに至る縦方向断面度数変化の５０％を与える位置を中心として縦方向へ±４ｍｍに位置する２本の水平線と、Ｆ１を通る縦方向の直線から水平方向へ±１５ｍｍに位置する２本の縦線で囲まれた矩形内の任意の位置において、
前記第１の屈折表面における表面非点収差量の微分値は、横方向微分値の絶対値よりも縦方向微分値の絶対値の方が大きく、
かつ、
前記矩形内の任意の位置において、
前記第１の屈折表面における表面平均度数の微分値は、横方向微分値の絶対値よりも縦方向微分値の絶対値の方が大きいことを特徴とする両面非球面型累進屈折力レンズ。
この構成によれば、特に、累進屈折力レンズの使用頻度の高い中央の領域で、物体側表面における縦方向累進作用の分担比率を高めることにより、物体側表面の面のねじれを減少させ、像のゆれや歪みを抑制することができる。また、表面非点収差量や表面平均度数を指標とすることにより、レンズの光学的性能の評価が容易となる。
（第２３の構成）
物体側表面である第１の屈折表面と、眼球側表面である第２の屈折表面とに分割配分されている累進屈折力作用を備えた両面非球面型累進屈折力レンズの設計方法であって、
前記第１の屈折表面において、遠用度数測定位置Ｆ１における横方向の表面屈折力及び縦方向の表面屈折力をそれぞれ、ＤＨｆ、ＤＶｆとし、
前記第１の屈折表面において、近用度数測定位置Ｎ１における横方向の表面屈折力及び縦方向の表面屈折力をそれぞれＤＨｎ、ＤＶｎとするとき、
ＤＶｎ−ＤＶｆ＞ＡＤＤ／２
となる関係式を満足させると共に、前記第１の屈折表面のＦ１及びＮ１における表面非点収差成分を、前記第２の屈折表面にて相殺し、前記第１と第２の屈折表面とを合わせて処方値に基づいた加入度数（ＡＤＤ）を与えるようにし、
かつ、
Ｆ１を通る縦方向断面曲線において、Ｆ１からＮ１と同じ高さに至る縦方向断面度数変化の５０％を与える位置を中心として縦方向へ±４ｍｍに位置する２本の水平線と、Ｆ１を通る縦方向の直線から水平方向へ±１５ｍｍに位置する２本の縦線で囲まれた矩形内の任意の位置において、
前記第１の屈折表面における表面縦方向断面度数の微分値は、横方向微分値の絶対値よりも縦方向微分値の絶対値の方を大きくすることを特徴とする両面非球面型累進屈折力レンズの設計方法。
この構成によれば、特に、累進屈折力レンズの使用頻度の高い中央の領域で、物体側表面における縦方向累進作用の分担比率を高めることにより、物体側表面の面のねじれを減少させ、像のゆれや歪みを抑制することができる。
（第２４の構成）
物体側表面である第１の屈折表面と、眼球側表面である第２の屈折表面とに分割配分されている累進屈折力作用を備えた両面非球面型累進屈折力レンズの設計方法であって、
前記第１の屈折表面において、遠用度数測定位置Ｆ１における横方向の表面屈折力及び縦方向の表面屈折力をそれぞれ、ＤＨｆ、ＤＶｆとし、
前記第１の屈折表面において、近用度数測定位置Ｎ１における横方向の表面屈折力及び縦方向の表面屈折力をそれぞれＤＨｎ、ＤＶｎとするとき、
ＤＶｎ−ＤＶｆ＞ＡＤＤ／２
となる関係式を満足させると共に、前記第１の屈折表面のＦ１及びＮ１における表面非点収差成分を、前記第２の屈折表面にて相殺し、前記第１と第２の屈折表面とを合わせて処方値に基づいた加入度数（ＡＤＤ）を与えるようにし、
かつ、
Ｆ１を通る縦方向断面曲線において、Ｆ１からＮ１と同じ高さに至る縦方向断面度数変化の５０％を与える位置を中心として縦方向へ±４ｍｍに位置する２本の水平線と、Ｆ１を通る縦方向の直線から水平方向へ±１５ｍｍに位置する２本の縦線で囲まれた矩形内の任意の位置において、前記第１の屈折表面における表面非点収差量の微分値は、横方向微分値の絶対値よりも縦方向微分値の絶対値の方を大きく、
かつ、
前記矩形内の任意の位置において、
前記第１の屈折表面における表面平均度数の微分値は、横方向微分値の絶対値よりも縦方向微分値の絶対値の方を大きくすることを特徴とする両面非球面型累進屈折力レンズの設計方法。
この構成によれば、特に、累進屈折力レンズの使用頻度の高い中央の領域で、物体側表面における縦方向累進作用の分担比率を高めることにより、物体側表面の面のねじれを減少させ、像のゆれや歪みを抑制することができる。また、表面非点収差量や表面平均度数を指標とすることにより、レンズの光学的性能の評価が容易となる。 (First configuration)
A double-sided aspherical progressive-power lens having a progressive-power action divided and distributed into a first refractive surface that is an object-side surface and a second refractive surface that is an eyeball-side surface,
In the first refractive surface, the horizontal surface power and the vertical surface power at the distance power measurement position F1 are DHf and DVf, respectively.
In the first refracting surface, when the horizontal surface power and the vertical surface power at the near power measurement position N1 are DHn and DVn, respectively,
DHf + DHn <DVf + DVn and DHn <DVn
Is satisfied, and the surface astigmatism components at F1 and N1 of the first refractive surface are canceled by the second refractive surface, and the first and second refractive surfaces are combined. To give the distance power (Df) and the addition power (ADD) based on the prescription value,
The distribution of astigmatism on the first refractive surface is symmetrical with respect to one meridian passing through the distance power measurement position F1, and the distribution of astigmatism on the second refractive surface is The arrangement of the near power measurement position N2 on the second refractive surface is asymmetrical with respect to a single meridian passing through the distance power measurement position F2 on the second refractive surface. A double-sided aspherical progressive-power lens, characterized in that it is centered on the side.
According to this configuration, by increasing the sharing ratio of the lateral progressive action on the eyeball side surface, the field of view spreads in the horizontal direction, and by increasing the sharing ratio of the vertical progressive action on the object side surface, It is possible to provide a progressive power lens that has a wide binocular visual field that is easy to move in the line of sight, has little astigmatism, and is distorted when worn and has little distortion.
(Second configuration)
In the double-sided aspherical progressive-power lens refractive power lens according to the first configuration,
The double-sided aspherical progressive-power lens is characterized in that the transmission astigmatism distribution in the near portion of the double-sided aspherical progressive-power lens is arranged so that the nose side is dense and the temple side is sparse. .
According to this configuration, in addition to the effect of the first configuration, transmission astigmatism from the near portion to the side is approximated by the left and right eyes, and better binocular vision is possible.
(Third configuration)
A design method of a double-sided aspherical progressive-power lens having a progressive-power action divided and distributed into a first refractive surface that is an object-side surface and a second refractive surface that is an eyeball-side surface, ,
In the first refractive surface, the horizontal surface power and the vertical surface power at the distance power measurement position F1 are DHf and DVf, respectively.
In the first refracting surface, when the horizontal surface power and the vertical surface power at the near power measurement position N1 are DHn and DVn, respectively,
DHf + DHn <DVf + DVn and DHn <DVn
Is satisfied, and the surface astigmatism components at F1 and N1 of the first refractive surface are canceled by the second refractive surface, and the first and second refractive surfaces are combined. To give the distance power (Df) and the addition power (ADD) based on the prescription value,
The distribution of astigmatism on the first refractive surface is symmetrical with respect to one meridian passing through the distance power measurement position F1, and the distribution of astigmatism on the second refractive surface is The arrangement of the near power measurement position N2 on the second refractive surface is asymmetrical with respect to a single meridian passing through the distance power measurement position F2 on the second refractive surface. A method for designing a double-sided aspherical progressive-power lens, characterized in that the lens is centered on the side.
According to this configuration, by increasing the sharing ratio of the lateral progressive action on the eyeball side surface, the field of view spreads in the horizontal direction, and by increasing the sharing ratio of the vertical progressive action on the object side surface, It is possible to provide a design method capable of obtaining a progressive power lens that is easy to move in the line of sight, has a wide binocular field of view with little astigmatism, is distorted during wearing, and has little distortion.
(Fourth configuration)
In the design method of the double-sided aspherical progressive-power lens according to the third configuration,
The double-sided aspherical progressive-power lens is characterized in that the transmission astigmatism distribution in the near portion of the double-sided aspherical progressive-power lens is arranged so that the nose side is dense and the temple side is sparse. Design method.
According to this configuration, in addition to the effects of the third configuration, transmission astigmatism from the near portion to the side is approximated by the left and right eyes, and better binocular vision is possible.
(Fifth configuration)
A double-sided aspherical progressive-power lens having a progressive-power action divided and distributed into a first refractive surface that is an object-side surface and a second refractive surface that is an eyeball-side surface,
In the first refractive surface, the horizontal surface power and the vertical surface power at the distance power measurement position F1 are DHf and DVf, respectively.
In the first refracting surface, when the horizontal surface power and the vertical surface power at the near power measurement position N1 are DHn and DVn, respectively,
DHf + DHn <DVf + DVn and DHn <DVn
Is satisfied, and the surface astigmatism components at F1 and N1 of the first refractive surface are canceled by the second refractive surface, and the first and second refractive surfaces are combined. To give the distance power (Df) and the addition power (ADD) based on the prescription value,
The distribution of the average power of the first refractive surface is symmetrical with respect to one meridian passing through the distance power measurement position F1, and the distribution of the average power of the second refractive surface is the second power distribution. The arrangement of the near power measurement position N2 on the second refracting surface is asymmetrical with respect to the nose side with respect to a single meridian passing through the distance power measurement position F2 on the refractive surface. A double-sided aspherical progressive-power lens, characterized in that
According to this configuration, by increasing the sharing ratio of the lateral progressive action on the eyeball side surface, the field of view spreads in the horizontal direction, and by increasing the sharing ratio of the vertical progressive action on the object side surface, It is possible to provide a progressive power lens that is easy to move the line of sight, has a wide binocular field of view with an appropriate average power, and is less distorted, distorted, and blurred when worn.
(Sixth configuration)
In the double-sided aspherical progressive-power lens according to the fifth configuration,
A double-sided aspherical progressive-power lens having a double-sided aspherical progressive-power lens in which the transmission average power distribution in the near portion of the double-sided aspherical progressive-power lens is arranged so that the nose side is dense and the temple side is sparse.
According to this configuration, in addition to the effect of the fifth configuration, the transmission average power from the near portion to the side is approximated by the left and right eyes, and better binocular vision is possible.
(Seventh configuration)
A design method of a double-sided aspherical progressive-power lens having a progressive-power action divided and distributed into a first refractive surface that is an object-side surface and a second refractive surface that is an eyeball-side surface, ,
In the first refractive surface, the horizontal surface power and the vertical surface power at the distance power measurement position F1 are DHf and DVf, respectively.
In the first refracting surface, when the horizontal surface power and the vertical surface power at the near power measurement position N1 are DHn and DVn, respectively,
DHf + DHn <DVf + DVn and DHn <DVn
Is satisfied, and the surface astigmatism components at F1 and N1 of the first refractive surface are canceled by the second refractive surface, and the first and second refractive surfaces are combined. To give the distance power (Df) and the addition power (ADD) based on the prescription value,
The distribution of the average power of the first refractive surface is symmetrical with respect to one meridian passing through the distance power measurement position F1, and the distribution of the average power of the second refractive surface is the second power distribution. The arrangement of the near power measurement position N2 on the second refracting surface is asymmetrical with respect to the nose side with respect to a single meridian passing through the distance power measurement position F2 on the refractive surface. A method for designing a double-sided aspherical progressive-power lens, characterized in that:
According to this configuration, by increasing the sharing ratio of the lateral progressive action on the eyeball side surface, the field of view spreads in the horizontal direction, and by increasing the sharing ratio of the vertical progressive action on the object side surface, It is possible to provide a design method capable of obtaining a progressive-power lens that can easily move the line of sight, has a wide binocular visual field with an appropriate average power, and is less distorted, distorted, and blurred during wearing.
(Eighth configuration)
In the design method of the double-sided aspherical progressive-power lens according to the seventh configuration,
A method for designing a double-sided aspherical progressive-power lens, characterized in that the transmission average power distribution in the near portion of the double-sided aspherical progressive-power lens is arranged so that the nose side is dense and the temple side is sparse .
According to this configuration, in addition to the effects of the seventh configuration, the transmission average power from the near portion to the side is approximated by the left and right eyes, and better binocular vision is possible.
(Ninth configuration)
A double-sided aspherical progressive-power lens having a progressive-power action divided and distributed on a first refractive surface that is an object-side surface and a second refractive surface that is an eyeball-side surface;
In the first refracting surface, when the horizontal surface power and the vertical surface power at the near power measurement position N1 are DHn and DVn, respectively,
DVn-DHn> ADD / 2
Satisfying the following relational expression, canceling out the surface astigmatism component at N1 of the first refractive surface with the second refractive surface, and combining the first and second refractive surfaces, A double-sided aspherical progressive-power lens, characterized in that it provides a near power (Dn) based on the value.
According to this configuration, in particular, in the near portion, by increasing the sharing ratio of the lateral progressive action on the eyeball side surface, the field of view spreads in the horizontal direction, and at the same time, the sharing ratio of the vertical progressive action on the object side surface. Therefore, it is possible to provide a progressive-power lens that is easy to move from near and far, and that is distorted when worn and has little distortion.
(Tenth configuration)
In the ninth configuration, the double-sided aspherical progressive-power lens according to this aspect,
In the first refractive surface, when the lateral surface refractive power and the vertical surface refractive power at the distance power measurement position F1 are DHf and DVf, respectively,
DHf + DHn <DVf + DVn, and DVn−DVf> ADD / 2, and
DHn-DHf <ADD / 2
And the astigmatism component at F1 and N1 of the first refractive surface is canceled by the second refractive surface, and the first and second refractive surfaces are combined. A double-sided aspherical progressive-power lens characterized in that it provides a distance power (Df) and an addition power (ADD) based on a prescription value.
According to this configuration, in addition to the effect of the ninth configuration, it is possible to provide a progressive power lens in which the distance portion and the entire lens surface are prevented from being shaken or distorted.
(Eleventh configuration)
In the double-sided aspherical progressive-power lens according to the ninth or tenth configuration,
The first refractive surface is symmetrical with respect to a meridian passing through the distance power measurement position F1, and the second refractive surface is a distance power measurement position F2 of the second refractive surface. And the arrangement of the near power measurement position N2 on the second refractive surface is inset to the nose side by a predetermined distance. Double-sided aspheric progressive power lens.
According to this configuration, in addition to the effects of the ninth or tenth configuration, a wider binocular visual field can be given, particularly when the line of sight is moved from the distance portion to the near portion.
(Twelfth configuration)
In the double-sided aspherical progressive-power lens according to any one of the ninth to eleventh aspects,
The first refracting surface is a rotating surface with a meridian passing through the distance power measurement position F1 as a generating line, and the second refracting surface is a distance power measurement position of the second refracting surface. It is asymmetrical with respect to one meridian passing through F2, and the arrangement of the near-field power measurement position N2 on the second refractive surface is inset to the nose side by a predetermined distance. A double-sided aspherical progressive-power lens.
According to this configuration, in addition to the effects of any of the ninth to eleventh configurations, it is possible to prevent the surface of the object side from causing a twist of the surface that causes the image shake. Further, when the line of sight is moved from the distance portion to the near portion, a wider binocular visual field can be provided.
(13th configuration)
In the double-sided aspherical progressive-power lens according to any one of Items 9 to 11,
On the first refracting surface, the horizontal cross section curve passing through the distance power measurement position F1 is not a perfect circle but has a predetermined refractive power change, and an arbitrary position on the horizontal cross section curve. The double-sided aspherical progressive-power lens according to claim 1, wherein a cross-sectional curve by a vertical cross section including a normal line is substantially the same as a meridian passing through the distance power measurement position F1.
According to this configuration, in addition to the effects of any one of the ninth to eleventh configurations, by adopting the above configuration, it is possible to reduce left and right side distortion and improve the side field of view.
(14th configuration)
In the double-sided aspherical progressive-power lens according to any one of Items 9 to 13,
The first and second refractive surfaces are combined to provide a distance power (Df) and an addition power (ADD) based on a prescription value, and a prism refractive power (Pf) is provided as necessary. Above, aspheric correction has been made on at least one of the items of astigmatism and power error caused by the fact that the line of sight and the lens surface in the wearing state cannot be orthogonal to each other, and the occurrence of image distortion in the peripheral visual field. A double-sided aspherical progressive-power lens characterized by that.
According to this configuration, in addition to the effects of any of the ninth to thirteenth configurations, the above-described aspherical correction suppresses transmission astigmatism, transmission power error, and image distortion in the peripheral visual field. A progressive power lens can be provided.
(15th configuration)
This is a design method of a double-sided aspherical progressive power lens having a progressive power action divided and distributed on a first refractive surface that is an object side surface and a second refractive surface that is an eyeball side surface. And
In the first refracting surface, when the horizontal surface power and the vertical surface power at the near power measurement position N1 are DHn and DVn, respectively,
DVn-DHn> ADD / 2
Satisfying the following relational expression, canceling out the surface astigmatism component at N1 of the first refractive surface with the second refractive surface, and combining the first and second refractive surfaces, A design method for a double-sided aspherical progressive-power lens, characterized in that the near power (Dn) is based on the value.
According to this configuration, in particular, in the near portion, by increasing the sharing ratio of the lateral progressive action on the eyeball side surface, the field of view spreads in the horizontal direction, and at the same time, the sharing ratio of the vertical progressive action on the object side surface. Therefore, it is possible to provide a design method capable of obtaining a progressive power lens that is easy to move in the distance of perspective and that is distorted during wearing and has little distortion.
(Sixteenth configuration)
In the design method of a double-sided aspherical progressive-power lens according to the fifteenth configuration,
In the first refractive surface, when the lateral surface refractive power and the vertical surface refractive power at the distance power measurement position F1 are DHf and DVf, respectively,
DHf + DHn <DVf + DVn, and DVn−DVf> ADD / 2, and
DHn-DHf <ADD / 2
And the astigmatism component at F1 and N1 of the first refractive surface is canceled by the second refractive surface, and the first and second refractive surfaces are combined. A design method for a double-sided aspherical progressive-power lens, characterized by providing a distance diopter (Df) and an add power (ADD) based on a prescription value.
According to this configuration, in addition to the effect of the fifteenth configuration, it is possible to provide a design method capable of obtaining a progressive power lens in which vibration and distortion are suppressed in the distance portion and the entire lens surface.
(17th configuration)
In the design method of the double-sided aspherical progressive-power lens according to the fifteenth or sixteenth aspect,
The first refractive surface is symmetrical with respect to a meridian passing through the distance power measurement position F1, and the second refractive surface is a distance power measurement position F2 of the second refractive surface. And the arrangement of the near power measurement position N2 on the second refractive surface is inset to the nose side by a predetermined distance. To design a double-sided aspherical progressive-power lens.
According to this configuration, in addition to the effects of the fifteenth or sixteenth configuration, a wider binocular visual field can be given, particularly when the line of sight is moved from the distance portion to the near portion.
(18th configuration)
In the double-sided aspherical progressive-power lens designing method according to any one of the fifteenth to seventeenth aspects,
The first refracting surface is a rotating surface with a meridian passing through the distance power measurement position F1 as a generating line, and the second refracting surface is a distance power measurement position of the second refracting surface. It is asymmetrical with respect to one meridian passing through F2, and the arrangement of the near-field power measurement position N2 on the second refractive surface is inset to the nose side by a predetermined distance. A double-sided aspherical progressive-power lens design method.
According to this configuration, in addition to the effects of any one of the fifteenth to seventeenth configurations, it is possible to prevent the surface on the object side from being twisted on the surface that causes image distortion. Further, when the line of sight is moved from the distance portion to the near portion, a wider binocular visual field can be provided.
(19th configuration)
In the design method of a double-sided aspherical progressive-power lens according to any one of 15th to 17th,
In the first refracting surface, the horizontal cross section curve passing through the distance power measurement position F1 is not a perfect circle but has a predetermined refractive power change, and at any position on the horizontal cross section curve A method for designing a double-sided aspherical progressive-power lens, characterized in that a cross-sectional curve by a vertical cross section including a normal line is substantially the same as a meridian passing through the distance power measurement position F1.
According to this configuration, in addition to the effects of any one of the fifteenth to seventeenth configurations, by adopting the above configuration, it is possible to reduce the lateral distortion and to improve the lateral field of view.
(20th configuration)
In the design method of a double-sided aspherical progressive-power lens according to any one of fifteenth to nineteenth,
The first and second refractive surfaces are combined to provide a distance power (Df) and an addition power (ADD) based on a prescription value, and a prism refractive power (Pf) is provided as necessary. Above, aspheric correction has been made on at least one of the items of astigmatism and power error caused by the fact that the line of sight and the lens surface in the wearing state cannot be orthogonal to each other, and the occurrence of image distortion in the peripheral visual field. A design method for a double-sided aspherical progressive-power lens, characterized in that
According to this configuration, in addition to the effects of any one of the fifteenth to nineteenth configurations, the above-described aspheric correction suppresses transmission astigmatism, transmission power error, image distortion in the peripheral visual field, and the like. A design method capable of obtaining a progressive-power lens can be provided.
(21st configuration)
A double-sided aspherical progressive-power lens having a progressive-power action divided and distributed into a first refractive surface that is an object-side surface and a second refractive surface that is an eyeball-side surface,
In the first refractive surface, the horizontal surface power and the vertical surface power at the distance power measurement position F1 are DHf and DVf, respectively.
In the first refracting surface, when the horizontal surface power and the vertical surface power at the near power measurement position N1 are DHn and DVn, respectively,
DVn-DVf> ADD / 2
Is satisfied, and the surface astigmatism components at F1 and N1 of the first refractive surface are canceled by the second refractive surface, and the first and second refractive surfaces are combined. To give the addition power (ADD) based on the prescription value,
And,
In the longitudinal section curve passing through F1, two horizontal lines located ± 4 mm in the longitudinal direction centering on the position giving 50% of the longitudinal section frequency change from F1 to the same height as N1, and the longitudinal line passing through F1 At an arbitrary position within a rectangle surrounded by two vertical lines located ± 15 mm horizontally from the direction straight line,
A double-sided aspherical progressive-power lens characterized in that the absolute value of the longitudinal differential value of the differential value of the surface longitudinal cross-sectional power at the first refractive surface is larger than the absolute value of the lateral differential value .
According to this configuration, in particular, in the central region where the progressive-power lens is frequently used, by increasing the ratio of the longitudinal progressive action on the object-side surface, the twist of the surface on the object-side surface is reduced, and the image Can be suppressed.
(Twenty-second configuration)
A double-sided aspherical progressive-power lens having a progressive-power action divided and distributed into a first refractive surface that is an object-side surface and a second refractive surface that is an eyeball-side surface,
In the first refractive surface, the horizontal surface power and the vertical surface power at the distance power measurement position F1 are DHf and DVf, respectively.
In the first refracting surface, when the horizontal surface power and the vertical surface power at the near power measurement position N1 are DHn and DVn, respectively,
DVn-DVf> ADD / 2
Is satisfied, and the surface astigmatism components at F1 and N1 of the first refractive surface are canceled by the second refractive surface, and the first and second refractive surfaces are combined. To give the addition power (ADD) based on the prescription value,
And,
In the longitudinal section curve passing through F1, two horizontal lines located ± 4 mm in the longitudinal direction centering on the position giving 50% of the longitudinal section frequency change from F1 to the same height as N1, and the longitudinal line passing through F1 At an arbitrary position within a rectangle surrounded by two vertical lines located ± 15 mm horizontally from the direction straight line,
The differential value of the amount of surface astigmatism on the first refractive surface is greater in the absolute value of the longitudinal differential value than in the absolute value of the lateral differential value,
And,
At any position within the rectangle,
The double-sided aspherical progressive-power lens according to claim 1, wherein the differential value of the surface average power on the first refractive surface has a larger absolute value of the longitudinal differential value than an absolute value of the lateral differential value.
According to this configuration, in particular, in the central region where the progressive-power lens is frequently used, by increasing the ratio of the longitudinal progressive action on the object-side surface, the twist of the surface on the object-side surface is reduced, and the image Can be suppressed. In addition, by using the surface astigmatism amount and the surface average power as indices, it becomes easy to evaluate the optical performance of the lens.
(23rd configuration)
A design method of a double-sided aspherical progressive-power lens having a progressive-power action divided and distributed into a first refractive surface that is an object-side surface and a second refractive surface that is an eyeball-side surface, ,
In the first refractive surface, the horizontal surface power and the vertical surface power at the distance power measurement position F1 are DHf and DVf, respectively.
In the first refracting surface, when the horizontal surface power and the vertical surface power at the near power measurement position N1 are DHn and DVn, respectively,
DVn-DVf> ADD / 2
Is satisfied, and the surface astigmatism components at F1 and N1 of the first refractive surface are canceled by the second refractive surface, and the first and second refractive surfaces are combined. To give the addition power (ADD) based on the prescription value,
And,
In the longitudinal section curve passing through F1, two horizontal lines located ± 4 mm in the longitudinal direction centering on the position giving 50% of the longitudinal section frequency change from F1 to the same height as N1, and the longitudinal line passing through F1 At an arbitrary position within a rectangle surrounded by two vertical lines located ± 15 mm horizontally from the direction straight line,
The differential value of the surface longitudinal direction cross-sectional power at the first refractive surface is such that the absolute value of the longitudinal differential value is larger than the absolute value of the lateral differential value, and the double-sided aspherical progressive power is characterized in that Lens design method.
According to this configuration, in particular, in the central region where the progressive-power lens is frequently used, by increasing the ratio of the longitudinal progressive action on the object-side surface, the twist of the surface on the object-side surface is reduced, and the image Can be suppressed.
(24th configuration)
A design method of a double-sided aspherical progressive-power lens having a progressive-power action divided and distributed into a first refractive surface that is an object-side surface and a second refractive surface that is an eyeball-side surface, ,
In the first refractive surface, the horizontal surface power and the vertical surface power at the distance power measurement position F1 are DHf and DVf, respectively.
In the first refracting surface, when the horizontal surface power and the vertical surface power at the near power measurement position N1 are DHn and DVn, respectively,
DVn-DVf> ADD / 2
Is satisfied, and the surface astigmatism components at F1 and N1 of the first refractive surface are canceled by the second refractive surface, and the first and second refractive surfaces are combined. To give the addition power (ADD) based on the prescription value,
And,
In the longitudinal section curve passing through F1, two horizontal lines located ± 4 mm in the longitudinal direction centering on the position giving 50% of the longitudinal section frequency change from F1 to the same height as N1, and the longitudinal line passing through F1 The differential value of the amount of surface astigmatism on the first refractive surface is a lateral differential value at an arbitrary position within a rectangle surrounded by two vertical lines located ± 15 mm in the horizontal direction from the straight line in the direction. The absolute value of the longitudinal differential value is larger than the absolute value of
And,
At any position within the rectangle,
The differential value of the surface average power on the first refractive surface is such that the absolute value of the longitudinal differential value is larger than the absolute value of the lateral differential value. Design method.
According to this configuration, in particular, in the central region where the progressive-power lens is frequently used, by increasing the ratio of the longitudinal progressive action on the object-side surface, the twist of the surface on the object-side surface is reduced, and the image Can be suppressed. In addition, by using the surface astigmatism amount and the surface average power as indices, it becomes easy to evaluate the optical performance of the lens.

本発明によれば、累進屈折力レンズの累進作用について、レンズの縦方向と横方向とに分割した上で、各々の方向に対して最適な物体側、眼球側の表裏２面の分担比率を定め、一枚の両面非球面型累進屈折力レンズを構成し、裏面（眼球側表面）における横方向累進作用の分担比率を高くすることにより、水平方向に視界が広がるという利点を享受できるとともに、表面（物体側表面）における縦方向累進作用の分担比率を高くすることにより、垂直方向には遠近の眼球回旋角が増すという欠点を抑えることが可能となった。
さらに、累進屈折力レンズにおいて、遠用部と近用部とにおける像の倍率差を低減することにより、装用時における歪みの少ない広範囲な有効視野を与えることもできた。
また、累進屈折力レンズの物体側表面として「左右対称の半完成品」を用い、受注後に眼球側表面のみを近方視における眼の輻湊作用に対応した左右非対称な曲面として加工することも可能であり、加工時間とコストとを低減させることができる。 According to the present invention, the progressive action of the progressive power lens is divided into the longitudinal direction and the lateral direction of the lens, and the optimal ratio of the front and back surfaces on the object side and the eyeball side in each direction is determined. By defining a single double-sided aspherical progressive-power lens and increasing the sharing ratio of the lateral progressive action on the back (eyeball side surface), you can enjoy the advantage that the field of view spreads in the horizontal direction, By increasing the ratio of the longitudinal progressive action on the surface (object-side surface), it has become possible to suppress the disadvantage that the eyeball rotation angle in the near direction increases in the vertical direction.
Further, in the progressive-power lens, by reducing the difference in magnification of the image between the distance portion and the near portion, it was possible to provide a wide effective field of view with little distortion during wearing.
It is also possible to use a "symmetrical semi-finished product" as the object-side surface of the progressive-power lens, and after the order is received, only the eyeball-side surface can be processed as a left-right asymmetric curved surface corresponding to the eye convergence in near vision Thus, the processing time and cost can be reduced.

以下、図面を参照しながら、本発明の実施の形態について説明する。尚、当該説明において、前段部では本発明者らの解明過程について説明し、後段では当該解明結果に基づいた本発明に係る両面非球面型累進屈折力レンズについて説明する。 Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the above description, the elucidation process of the present inventors will be described in the former part, and the double-sided aspherical progressive-power lens according to the present invention based on the elucidation result will be described in the latter part.

ここで、図１は眼鏡レンズ表面の各位置における各種の表面屈折力の説明図、図２は眼球と視線とレンズとの位置関係の説明図、図３−１、図３−２及び図３−３並びに図４−１、図４−２及び図４−３はプリズムの倍率Ｍγに関する説明図であってプラスレンズとマイナスレンズによる違い、主としてレンズの下部である近用部を用いて眺めた場合の倍率の違いに関する説明図、図５−１は累進屈折力レンズの光学的レイアウトの説明図であって累進屈折力レンズを物体側表面から眺めた正面図、図５−２は累進屈折力レンズの光学的レイアウトの説明図であって縦方向の断面を表す側面図、図５−３は累進屈折力レンズの光学的レイアウトの説明図であって横方向の断面を表す立面図、図６は「加入度数」の定義の違いを示す説明図である。なお、これらの図において、符号Ｆは遠用度数測定位置、Ｎは近用度数測定位置、Ｑはプリズム度数測定位置を示す。また、図１等に記した他の符号は、
ＤＶｆ：Ｆを通る縦方向断面曲線の、Ｆにおける表面屈折力
ＤＶｎ：Ｎを通る縦方向断面曲線の、Ｎにおける表面屈折力
ＤＨｆ：Ｆを通る横方向断面曲線の、Ｆにおける表面屈折力
ＤＨｎ：Ｎを通る横方向断面曲線の、Ｎにおける表面屈折力
を表している。さらに、図の屈折表面が物体側表面である第１の屈折表面である場合には全ての符号に添字１を付し、眼球側表面である第２の屈折表面である場合には全ての符号に添字２を付して識別する。 Here, FIG. 1 is an explanatory diagram of various surface refractive powers at various positions on the surface of the spectacle lens, FIG. 2 is an explanatory diagram of the positional relationship between the eyeball, the line of sight, and the lens, and FIGS. 3-1, 3-2 and 3 -3 and FIGS. 4-1, 4-2, and 4-3 are explanatory diagrams relating to the magnification Mγ of the prism. The difference between the plus lens and the minus lens, mainly viewed using the near portion at the bottom of the lens. FIG. 5A is an explanatory diagram of the optical layout of the progressive addition lens, FIG. 5B is a front view of the progressive addition lens viewed from the object side surface, and FIG. FIG. 5C is an explanatory view of the optical layout of the lens, and is a side view showing the cross section in the vertical direction; FIG. 5C is an explanatory view of the optical layout of the progressive power lens, and an elevation view showing the cross section in the horizontal direction; 6 is an explanatory diagram showing the difference in the definition of “additional power”. . In these drawings, symbol F indicates a distance power measurement position, N indicates a near power measurement position, and Q indicates a prism power measurement position. In addition, the other symbols shown in FIG.
DVf: Surface refractive power at F of the longitudinal section curve through F DVn: Surface refractive power at N of the longitudinal section curve through N DHf: Surface refractive power at F of the transverse section curve through F DHn: It represents the surface power at N of the transverse cross-section curve through N. Further, when the refractive surface in the figure is the first refractive surface that is the object-side surface, the suffix 1 is attached to all symbols, and when the refractive surface is the second refractive surface that is the eyeball-side surface, all symbols are denoted. Is identified by subscript 2.

また、符号Ｆ１及びＦ２は物体側表面と眼球側表面の遠用度数測定位置、同様にＮ１及びＮ２は物体側表面と眼球側表面の近用度数測定位置を示す。さらに、Ｅは眼球、Ｃは眼球の回旋中心点、ＳはＣを中心とした参照球面、Ｌｆ及びＬｎはそれぞれ遠用度数測定位置と近用度数測定位置を通る視線である。また、Ｍは正面上方から下方まで両眼視したときの視線が通過する、主注視線と呼ばれる曲線である。そして、Ｆ１、Ｎ１、Ｆ２、Ｎ２、Ｎ３は、「加入度数」の定義によって異なるレンズメーターの開口部を当てる部位を示している。 Symbols F1 and F2 indicate distance power measurement positions on the object side surface and the eyeball side surface, and similarly N1 and N2 indicate near power measurement positions on the object side surface and the eyeball side surface. Further, E is the eyeball, C is the center of rotation of the eyeball, S is the reference spherical surface centered on C, and Lf and Ln are the lines of sight passing through the distance power measurement position and the near power measurement position, respectively. Further, M is a curve called a main gazing line through which the line of sight passes when viewed from both front and below with both eyes. F1, N1, F2, N2, and N3 indicate portions to which different lens meter openings are applied according to the definition of “additional power”.

［解明過程］
本発明者らは、上記従来技にて説明した（ａ）の課題である「パラメータを近用部に対応させる」ことと、（ｄ）の課題である「対物距離を考慮すること」によって改善した近用部に対応した倍率の計算式は次のようにして求めることとした。すなわち、Ｍｐをパワーファクター、Ｍｓをシェープファクターとしたとき、像の倍率ＳＭは、
ＳＭ＝Ｍｐ×Ｍｓ…（１’）
で表される。ここで、視標までの対物パワー（ｍ単位で表した対物距離の逆数）をＰｘとし、レンズの近用部における眼球側の面から眼球までの距離をＬ、近用部における屈折力（近用部における内側頂点屈折力）をＰｏ、レンズの近用部における厚みをｔ、レンズの屈折率をｎ、レンズの近用部における物体側の面のベースカーブ（屈折力）をＰｂとすると、以下の関係が成立する。
Ｍｐ＝（１−（Ｌ＋ｔ）Ｐｘ）／（１−Ｌ×Ｐｏ）…（２’）
Ｍｓ＝１／（１−ｔ×（Ｐｘ＋Ｐｂ）／ｎ）…（３’） [Clarification process]
The present inventors have improved by “corresponding the parameter to the near part”, which is the problem (a) described in the above conventional technique, and “considering the objective distance”, which is the problem (d). The calculation formula for the magnification corresponding to the near-use part was determined as follows. That is, when Mp is a power factor and Ms is a shape factor, an image magnification SM is
SM = Mp × Ms (1 ′)
It is represented by Here, the objective power to the target (the reciprocal of the objective distance expressed in m) is Px, the distance from the eyeball side surface to the eyeball in the near part of the lens is L, and the refractive power (nearly in the near part). When the inner vertex refractive power of the lens portion is Po, the thickness of the near portion of the lens is t, the refractive index of the lens is n, and the base curve (refractive power) of the object side surface of the near portion of the lens is Pb, The following relationship holds.
Mp = (1− (L + t) Px) / (1−L × Po) (2 ′)
Ms = 1 / (1−t × (Px + Pb) / n) (3 ′)

これらの式において、各パラメータを遠用部に対応させ、対物距離のパワー表示であるＰｘに対して無限遠に対応した値である０を代入すると、前述の従来技術１の数式に一致する。即ち、従来技術１において用いられていた数式とは、「無限遠の対物距離である遠方視専用の数式」であったと考えられる。さて、ここで（１’）は、前述の従来技術１の数式と同一であるが、一般に、近方視の対物距離は０．３ｍ〜０．４ｍ程度なので、その逆数であるＰｘは−２．５〜−３．０程度の値となる。したがって、（２’）において分子の値が増えるのでＭｐの値は増大し、（３’）では分母の値が増えるのでＭｓの値は減
少する。即ち、近方視におけるシェープファクターＭｓの影響は、従来技術１の計算結果よりも少ないことがわかる。例えばＰｂ＝−Ｐｘ、即ち、レンズの物体側の面のベースカーブ（屈折力）が＋２．５〜＋３．０程度の値である場合には、Ｍｓ＝１となり、近方視におけるシェープファクターは像の倍率に全く無関係となることが解る。 In these equations, if each parameter is made to correspond to the distance portion and 0, which is a value corresponding to infinity, is substituted for Px which is the power display of the objective distance, the equation of the prior art 1 is matched. That is, it is considered that the mathematical formula used in the prior art 1 was “a special formula for far vision, which is an infinite objective distance”. Now, (1 ') is the same as the above-mentioned formula 1 of the prior art 1, but generally, the objective distance for near vision is about 0.3 m to 0.4 m, so the reciprocal Px is -2. The value is about .5 to -3.0. Therefore, the value of Mp increases because the value of the numerator increases in (2 ′), and the value of Ms decreases because the value of the denominator increases in (3 ′). That is, it can be seen that the influence of the shape factor Ms in near vision is less than the calculation result of the conventional technique 1. For example, when Pb = −Px, that is, when the base curve (refractive power) of the surface on the object side of the lens is a value of about +2.5 to +3.0, Ms = 1, and the shape factor in near vision is It can be seen that it is completely independent of the magnification of the image.

さて、以上のようにして各パラメータを近用部に対応させ、「対物距離」をも考慮した倍率の計算式を求めることが出来た。しかし、実際の近方視における倍率を算出するには、更に、前記従来技術１の（ｂ）の課題である「視線とレンズ面との角度」についても考慮しなければならない。ここで重要なことは「視線とレンズ面との角度」には方向性があるということである。そして、「視線とレンズ面との角度」を考慮するということは、前記従来技術１の（ｃ）の課題である「像の倍率」の方向性を同時に考慮するということに
他ならない。 Now, as described above, each parameter is made to correspond to the near portion, and a calculation formula for the magnification in consideration of the “object distance” can be obtained. However, in order to calculate the magnification in actual near vision, the “angle between the line of sight and the lens surface”, which is the problem of the prior art 1 (b), must also be considered. What is important here is that “the angle between the line of sight and the lens surface” has directionality. Considering the “angle between the line of sight and the lens surface” is nothing other than taking into account the directionality of the “image magnification”, which is the problem of the prior art 1 (c).

この観点で前述の（１’）〜（３’）における第１の計算式を見直すと、「視線とレンズ面との角度」が影響する計算ファクターとして、近用部における内側頂点屈折力Ｐｏと近用部における物体側の面のベースカーブ（屈折力）Ｐｂがある。ここで、近方視における視線と近用部領域の光軸とのなす角をα、近方視における視線と近用部における物体側表面の法線とのなす角をβとして、よく知られたＭａｒｔｉｎの近似式を用いると、
近用部における縦方向の内側頂点屈折力：Ｐｏｖ＝Ｐｏ×（１＋Ｓｉｎ²α×４／３）
近用部における横方向の内側頂点屈折力：Ｐｏｈ＝Ｐｏ×（１＋Ｓｉｎ²α×１／３）
近用部における物体側表面の縦断面屈折力：Ｐｂｖ＝Ｐｂ×（１＋Ｓｉｎ²β×４／３）
近用部における物体側表面の横断面屈折力：Ｐｂｈ＝Ｐｂ×（１＋Ｓｉｎ²β×１／３）
となる。このように、角αやβ、及びＰｏやＰｂがゼロでない限り、屈折力やパワーファクター、シェープファクターなどは縦横で異なる値となり、その結果、縦方向と横方向との倍率に差が生じてくるのである。 From this point of view, when reexamining the first calculation formulas in the above (1 ′) to (3 ′), the inner vertex power Po in the near portion is calculated as a calculation factor influenced by the “angle between the line of sight and the lens surface”. There is a base curve (refractive power) Pb of the object side surface in the near portion. Here, the angle between the line of sight in near vision and the optical axis of the near vision area is α, and the angle between the line of sight in near vision and the normal of the object side surface in the near vision area is β. Using Martin's approximation,
Longitudinal inner refractive power in the near portion: Pov = Po × (1 + Sin ² α × 4/3)
Lateral inner vertex power in the near portion: Poh = Po × (1 + Sin ² α × 1/3)
Longitudinal refractive power of object side surface in near portion: Pbv = Pb × (1 + Sin ² β × 4/3)
Cross-sectional refractive power of object side surface at near portion: Pbh = Pb × (1 + Sin ² β × 1/3)
It becomes. Thus, as long as the angles α and β, and Po and Pb are not zero, the refractive power, power factor, shape factor, and the like are different values in the vertical and horizontal directions. As a result, there is a difference in magnification between the vertical and horizontal directions. It will come.

ここでは「視線の方向に応じて屈折力が変わる」ことを簡単に説明するために近似式を用いたが、実際の光学設計においては厳密な光線追跡計算によってこれらの値を求めることが望ましい。これらの計算方法の非限定的な一例について説明する。
まず、スネルの法則を用いて視線に沿った光路を計算し、Ｌ、ｔ及び、物体側屈折面から物点までの距離を算出する。次に、この光路に沿って、微分幾何学における第１基本形式、第２基本形式、Ｗｅｉｎｇａｒｔｅｎの式などを用いることによって、レンズの物体側屈折面及び、眼球側屈折面における光路上での屈折の影響を考慮にいれた屈折力を計算することが出来る。これらの式や計算方法は極めて古くから公知であり、たとえば公知文献「微分幾何学」（矢野健太郎著（株）朝倉書店発行初版１９４９年）などに記載されているので説明は省略する。 Here, an approximate expression is used in order to simply explain that “the refractive power changes according to the direction of the line of sight”. However, in an actual optical design, it is desirable to obtain these values by strict ray tracing calculation. A non-limiting example of these calculation methods will be described.
First, the optical path along the line of sight is calculated using Snell's law, and L, t, and the distance from the object-side refractive surface to the object point are calculated. Next, along this optical path, by using the first basic form, the second basic form, Weingarten's formula, etc. in differential geometry, the refraction on the optical path on the object side refractive surface and the eyeball side refractive surface of the lens is performed. The refractive power can be calculated taking into account the influence of These formulas and calculation methods have been known for a very long time. For example, they are described in the known document “differential geometry” (published by Kentaro Yano (published by Asakura Shoten Co., Ltd., first edition, 1949)), and the description thereof will be omitted.

さて、このように厳密な光線追跡計算を行なうことで、前記従来技術１における（ａ）〜（ｄ）の課題であったＬ、Ｐｏ、ｔ、Ｐｂの４個の計算ファクターについての考慮もなされ、レンズ中心から大きく下方に位置する近用部はもちろん、全ての視線方向において厳密な倍率計算が可能となる。
このようにして前述の項目、
近用部における縦方向の内側頂点屈折力：Ｐｏｖ
近用部における横方向の内側頂点屈折力：Ｐｏｈ
近用部における物体側表面の縦断面屈折力：Ｐｂｖ
近用部における物体側表面の横断面屈折力：Ｐｂｈ
について、Ｍａｒｔｉｎの近似式を用いるよりも更に高い精度で求められるのである。 By performing the exact ray tracing calculation in this way, the four calculation factors L, Po, t, and Pb, which are the problems of (a) to (d) in the conventional technique 1, are also considered. In addition to the near-use portion located greatly below the center of the lens, it is possible to perform a precise magnification calculation in all viewing directions.
In this way,
Longitudinal inner vertex power in the near portion: Pov
Lateral inner vertex power in the near portion: Poh
Longitudinal section refractive power of object side surface at near portion: Pbv
Cross-sectional refractive power of object side surface at near portion: Pbh
Is obtained with higher accuracy than using Martin's approximate expression.

このように、「視線の方向に応じて屈折力が変わる」ことから、前述した像の倍率計算においても、全て視線方向の違いに対応させるべきことも容易に理解される。ここで、Ｍｐをパワーファクター、Ｍｓをシェープファクターとし、縦方向についてはｖ、横方向についてはｈの添字を付けて表すと、像の倍率ＳＭについて、前述の（１’）〜（３’）の式は、次のように書き換えられる。
ＳＭｖ＝Ｍｐｖ×Ｍｓｖ…（１ｖ’）
ＳＭｈ＝Ｍｐｈ×Ｍｓｈ…（１ｈ’）
Ｍｐｖ＝（１−（Ｌ＋ｔ）Ｐｘ）／（１−Ｌ×Ｐｏｖ）…（２ｖ’）
Ｍｐｈ＝（１−（Ｌ＋ｔ）Ｐｘ）／（１−Ｌ×Ｐｏｈ）…（２ｈ’）
Ｍｓｖ＝１／（１−ｔ×（Ｐｘ＋Ｐｂｖ）／ｎ）…（３ｖ’）
Ｍｓｈ＝１／（１−ｔ×（Ｐｘ＋Ｐｂｈ）／ｎ）…（３ｈ’）
以上のようにして、前記従来技術１の課題（ａ）から（ｄ）までに対応することが出来た。 Thus, since “refractive power changes according to the direction of the line of sight”, it can be easily understood that all of the above-described image magnification calculations should correspond to the difference in the direction of the line of sight. Here, when Mp is a power factor, Ms is a shape factor, and v is added in the vertical direction and h is added in the horizontal direction, the above-described (1 ′) to (3 ′) are described with respect to the image magnification SM. Is rewritten as follows.
SMv = Mpv × Msv (1v ′)
SMh = Mph × Msh (1h ′)
Mpv = (1− (L + t) Px) / (1−L × Pov) (2v ′)
Mph = (1− (L + t) Px) / (1−L × Poh) (2h ′)
Msv = 1 / (1−t × (Px + Pbv) / n) (3v ′)
Msh = 1 / (1-t × (Px + Pbh) / n) (3h ′)
As described above, the problems (a) to (d) of the prior art 1 can be dealt with.

最後に、実際の近方視における倍率を算出する上での、前述の従来技術１の課題（ｅ）である「プリズム作用による影響」について述べる。
プリズムそのものに、レンズのような屈折力は存在しないが、プリズムへの光線の入射角度や出射角度によってプリズムの倍率Ｍγが変化する。ここで、図３−１および図４−１の左側の如く、真空中から屈折率ｎの媒質中に入射した光線が媒質表面で屈折する場合の角倍率γを考える。このときの入射角をｉ、屈折角をｒとしたとき、良く知られたＳｎｅｌｌの法則により
ｎ＝Ｓｉｎｉ／Ｓｉｎｒ
である。また、屈折による角倍率γは、
γ＝Ｃｏｓｉ／Ｃｏｓｒ
で表される。ここで、ｎ≧１であるから、一般にｉ≧ｒとなりγ≦１となる。ここでγが最大値１となるのはｉ＝ｒ＝０、即ち垂直入射の場合である。また、屈折角ｒが
ｎ＝１／Ｓｉｎｒとなるとき、γは理論上の最小値
γ＝０
となる。このとき
ｉ＝π／２
であり、ｒは媒質中から光線が出る場合の全反射の臨界角に等しい。 Finally, “impact by prism action”, which is the problem (e) of the above-described prior art 1, in calculating the magnification in actual near vision will be described.
The prism itself does not have a refracting power like a lens, but the magnification Mγ of the prism changes depending on the incident angle and the outgoing angle of the light beam to the prism. Here, as shown on the left side of FIG. 3A and FIG. 4A, the angular magnification γ in the case where a light beam incident from a vacuum into a medium having a refractive index n is refracted on the medium surface is considered. When the incident angle is i and the refraction angle is r, n = Sin i / Sin r according to the well-known Snell's law.
It is. Also, the angular magnification γ due to refraction is
γ = Cos i / Cos r
It is represented by Here, since n ≧ 1, generally i ≧ r and γ ≦ 1. Here, γ has a maximum value of 1 when i = r = 0, that is, in the case of normal incidence. The refraction angle r is
When n = 1 / Sin r, γ is the theoretical minimum value γ = 0
It becomes. At this time, i = π / 2
And r is equal to the critical angle of total reflection when a light ray comes out of the medium.

一方、図３−１および図４−１の右側の如く、屈折率ｎの媒質から真空中へ、光線が出る場合の角倍率γ’は上記と全く逆となる。即ち、媒質内部から媒質表面で屈折して真空中に光線が出る場合の入射角をｉ’、屈折角をｒ’としたとき、Ｓｎｅｌｌの法則は
１／ｎ＝Ｓｉｎｉ’／Ｓｉｎｒ’
となり、角倍率は
γ’＝Ｃｏｓｉ’／Ｃｏｓｒ’
で表される。ｎ≧１であるから、一般にｒ’≧ｉ’となりγ’≧１となる。ここで、γ’が最小値１となるのは
ｉ’＝ｒ’＝０、
即ち垂直入射の場合である。また、入射角ｉ’が
ｎ＝１／Ｓｉｎｉ’
となるとき、γ’は理論上の最大値 γ’＝∞となる。このときｒ’＝π／２であり、ｉ’は媒質中から光線が出る場合の全反射の臨界角に等しい。 On the other hand, as shown on the right side of FIGS. 3-1 and 4-1, the angular magnification γ ′ when a light ray is emitted from a medium having a refractive index n into a vacuum is completely opposite to the above. That is, when the incident angle is i ′ and the refraction angle is r ′ when the light beam is refracted from the inside of the medium and is emitted into the vacuum, Snell's law is 1 / n = Sin i ′ / Sin r ′.
The angular magnification is γ ′ = Cos i ′ / Cos r ′
It is represented by Since n ≧ 1, in general, r ′ ≧ i ′ and γ ′ ≧ 1. Here, the minimum value 1 of γ ′ is i ′ = r ′ = 0,
That is, in the case of normal incidence. The incident angle i ′ is n = 1 / Sin i ′.
Γ ′ is the theoretical maximum value γ ′ = ∞. At this time, r ′ = π / 2, and i ′ is equal to the critical angle of total reflection when a light ray is emitted from the medium.

図３−３および図４−３の如く、一枚の眼鏡レンズの物体側表面に入射した光線がレンズ内部を通過し、眼球側表面から出射して眼球に到達する場合を考える（以後、説明の簡略化のために簡易的に、空気の屈折率は、真空中と同じ１に近似して考えることとする。）。眼鏡レンズの屈折率をｎ、物体側表面に入射した光線の入射角をｉ、屈折角をｒとし、レンズ内部から眼球側表面に到達した光線の入射角をｉ’、出射した光線の屈折角をｒ’とすると、眼鏡レンズの二つの表面を透過した角倍率Ｍγは前述の２種類の角倍率の積で表わされ、
Ｍγ＝γ×γ’＝（Ｃｏｓｉ×Ｃｏｓｉ’）／（Ｃｏｓｒ×Ｃｏｓｒ’）
となる。これは、レンズ表面の屈折力とは無関係であり、プリズムの倍率として知られている。 As shown in FIGS. 3-3 and 4-3, a case where a light beam incident on the object side surface of one spectacle lens passes through the inside of the lens, is emitted from the eyeball side surface, and reaches the eyeball (hereinafter described). For the sake of simplicity, the refractive index of air is assumed to be close to 1 as in vacuum). The refractive index of the spectacle lens is n, the incident angle of the light incident on the object side surface is i, the refraction angle is r, the incident angle of the light reaching the eyeball side surface from the inside of the lens is i ′, and the refraction angle of the emitted light. Is r ′, the angular magnification Mγ transmitted through the two surfaces of the spectacle lens is represented by the product of the above-mentioned two types of angular magnifications.
Mγ = γ × γ ′ = (Cos i × Cos i ′) / (Cos r × Cos r ′)
It becomes. This is independent of the refractive power of the lens surface and is known as the magnification of the prism.

ここで、図３−１および図４−１の如く、ｉ＝ｒ’，ｒ＝ｉ’ の場合を考えると、
Ｍγ＝γ×γ’＝１
となり、プリズムを通して見た像の倍率に変化がないことになる。ところが、図３−２の如く、眼鏡レンズの物体側表面に垂直に光線が入射した場合は、
Ｍγ＝γ’＝Ｃｏｓｉ’／Ｃｏｓｒ’≧１
となり、逆に、図４−２の如く、眼鏡レンズの眼球側表面から光線が垂直出射した場合は、
Ｍγ＝γ＝Ｃｏｓｉ／Ｃｏｓｒ≦１
となる。 Here, as shown in FIGS. 3-1 and 4-1, when i = r ′ and r = i ′,
Mγ = γ × γ ′ = 1
Thus, there is no change in the magnification of the image viewed through the prism. However, as shown in FIG. 3-2, when a light ray is incident on the object side surface of the spectacle lens perpendicularly,
Mγ = γ ′ = Cos i ′ / Cos r ′ ≧ 1
On the contrary, as shown in FIG. 4B, when a light beam is emitted vertically from the eyeball side surface of the spectacle lens,
Mγ = γ = Cos i / Cos r ≦ 1
It becomes.

ここで、重要なことは、これらのプリズムの倍率Ｍγには方向性があるということである。即ち、累進屈折力レンズにおけるプリズムの分布について考えると、度数や処方プリズム値によって異なるのは当然であるが、概してレンズ中央に近い遠方視におけるプリズムは少なく、レンズの下方に位置する近方視における縦方向のプリズムは大きい。従って、プリズムの倍率Ｍγは、特に近方視の縦方向に対して影響が大きいといえる。 Here, what is important is that the magnification Mγ of these prisms has directionality. That is, when considering the distribution of the prism in the progressive power lens, it is natural that it varies depending on the power and the prescription prism value, but in general there are few prisms in far vision near the center of the lens, and in near vision located below the lens. The vertical prism is large. Therefore, it can be said that the magnification Mγ of the prism has a great influence on the longitudinal direction of near vision.

累進屈折力レンズのみならず、眼鏡レンズは一般に物体側表面が凸であり、眼球側表面が凹であるメニスカス形状をしている、そして、近方視における視線が下向きであることを考え合わせると、図３−３に示すように、近用部が正の屈折力を有する累進屈折力レンズの近方視は、Ｍγ＝１である図３−１よりもＭγ≧１である図３−２の形状に近く、少なくともＭγ＞１と言える。同様に、図４−３に示すように、近用部が負の屈折力を有す
る累進屈折力レンズの近方視は、Ｍγ＝１である図４−１よりもＭγ≦１である図４−２の形状に近く、少なくともＭγ＜１と言える。従って、近用部が正の屈折力を有する累進屈折力レンズの近方視ではＭγ＞１であり、近用部が負の屈折力を有する累進屈折力レンズの近方視ではＭγ＜１となる。 Considering that not only progressive-power lenses but also spectacle lenses are generally meniscus shaped with a convex object-side surface and a concave eyeball-side surface, and the line of sight in near vision is downward. As shown in FIG. 3C, the near vision of the progressive addition lens in which the near portion has a positive refractive power is Mγ ≧ 1 than that in FIG. 3A where Mγ = 1. It can be said that at least Mγ> 1. Similarly, as shown in FIG. 4-3, the near vision of the progressive addition lens in which the near portion has a negative refractive power has Mγ ≦ 1 rather than FIG. 4-1 where Mγ = 1. It is close to the shape of −2, and it can be said that at least Mγ <1. Therefore, Mγ> 1 in the near vision of the progressive addition lens in which the near portion has a positive refractive power, and Mγ <1 in the near vision of the progressive addition lens in which the near portion has a negative refractive power. Become.

この結果、前記従来技術１におけるレンズの倍率ＳＭは、前述の如く、パワーファクターＭｐとシェープファクターＭｓとの積としてしか把握されていなかったのに対し、本発明では更にプリズムの倍率Ｍγを掛け合わせて、正しいレンズの倍率を得ようとするものである。 As a result, the lens magnification SM in the prior art 1 was grasped only as the product of the power factor Mp and the shape factor Ms as described above, whereas in the present invention, the magnification Mγ of the prism is further multiplied. Thus, it is intended to obtain a correct lens magnification.

このプリズムによる倍率Ｍγを、ＭｐやＭｓとの対比から「プリズムファクター」と呼ぶこととし、縦方向についてはｖ、横方向についてはｈの添字を付けて表すと、像の倍率（ＳＭ）について、前述の（１ｖ’）と（１ｈ’）の式は次のように書き換えられる。
ＳＭｖ＝Ｍｐｖ×Ｍｓｖ×Ｍγｖ…（１ｖ″）
ＳＭｈ＝Ｍｐｈ×Ｍｓｈ×Ｍγｈ…（１ｈ″）
なお、これらのＭγｖやＭγｈは、前述の厳密な光線追跡の計算過程において求めることが出来る。これにより、前述の眼鏡の倍率計算におけるプリズム作用による影響の課題を解決することが出来た。 The magnification Mγ by the prism is referred to as a “prism factor” in comparison with Mp and Ms. The above equations (1v ′) and (1h ′) can be rewritten as follows.
SMv = Mpv × Msv × Mγv (1v ″)
SMh = Mph × Msh × Mγh (1h ″)
These Mγv and Mγh can be obtained in the above-described strict ray tracing calculation process. Thereby, the problem of the influence by the prism action in the above-mentioned calculation of the magnification of the glasses could be solved.

通常の凸面累進屈折力レンズでは、物体側表面の「累進面」の表面屈折力が遠用部＜近用部となっている。これに対して前記従来技術１の累進屈折力レンズでは、物体側表面の「累進面」の表面屈折力を、遠用部＝近用部などとすることで、遠近のシェープファクターの割合を変え、遠近の像の倍率差を減少させることで累進屈折力レンズの像の歪みや揺れを改善しようとするものである。 In a normal convex progressive-power lens, the surface refractive power of the “progressive surface” on the object side surface is the distance portion <the near portion. On the other hand, in the progressive power lens of the prior art 1, the surface refractive power of the “progressive surface” on the object side surface is changed to the distance portion = the near portion, thereby changing the ratio of the shape factor in the distance. The objective is to improve the distortion and shaking of the progressive power lens image by reducing the magnification difference between the near and near images.

ところが、本願発明における考察では、物体側表面の「累進面」の遠近の表面屈折力差を少なくすることにより、横方向についての遠近の像の倍率差が減少するという利点が生ずるが、この利点は、縦方向について表面屈折力差を少なくすることには幾つかの問題のあることがわかった。 However, in the consideration of the present invention, there is an advantage that the difference in magnification of the perspective image in the lateral direction is reduced by reducing the surface refractive power difference in the perspective of the “progressive surface” on the object side surface. It has been found that there are several problems in reducing the surface refractive power difference in the longitudinal direction.

第１の問題は、縦方向のプリズムファクターＭγｖの影響である。
前述の如く縦方向のプリズムファクターＭγｖは、負の屈折力を有する場合にはＭγｖ＜１であり、正の屈折力を有する場合にはＭγｖ＞１となるが、その傾向は縦方向の表面屈折力差を少なくすることによって強められ、近用部の度数が正負いずれの場合にも、裸眼の倍率であるＭγｖ＝１から離れていく。ところが横方向のプリズムファクターＭγｈにはそのような影響はなく、Ｍγｈ＝１のままである。その結果、特に近用部から下方にかけての像の倍率に縦横の差が生じ、本来正方形に見えるべきものが、プラス度数にあって縦長に、マイナス度数にあっては横長に見えてしまうという不都合が生ずる。 The first problem is the influence of the vertical prism factor Mγv.
As described above, the longitudinal prism factor Mγv is Mγv <1 when it has a negative refractive power and Mγv> 1 when it has a positive refractive power. It is strengthened by reducing the force difference, and moves away from Mγv = 1, which is the magnification of the naked eye, when the power of the near portion is positive or negative. However, the prism factor Mγh in the horizontal direction has no such influence and Mγh = 1. As a result, there is a vertical and horizontal difference in the magnification of the image particularly from the near portion to the lower portion, and what is supposed to look like a square is in the positive frequency and in the vertical direction, and in the negative frequency, it looks in the horizontal direction. Will occur.

第２の問題は、特に近用部の縦方向が正の屈折力を有する場合にのみ起きる問題である。それは縦方向の表面屈折力差を少なくすることによって、近方視における視線とレンズ面との角度が更に斜めとなり、前述の縦方向のパワーファクターＭｐｖが増大し、第１の問題であった縦方向のプリズムファクターＭγｖの増大と重複して作用することにより、縦方向の倍率ＳＭｖが増大し、遠近の像の倍率差がかえって増大してしまうという不都合が生ずる。 The second problem is a problem that occurs only when the longitudinal direction of the near portion has a positive refractive power. By reducing the surface refractive power difference in the vertical direction, the angle between the line of sight and the lens surface in near vision becomes further oblique, the vertical power factor Mpv increases, and the vertical problem was the first problem. By acting in an overlapping manner with the increase in the prism factor Mγv in the direction, the longitudinal magnification SMv is increased, resulting in a disadvantage that the magnification difference between the near and far images is increased.

即ち、物体側表面である累進面の遠近の表面屈折力差を少なくすることは、横方向については利点があるが、縦方向についてはかえって改悪となることが判明した。従って、従来型の凸面累進屈折力レンズにおいて、物体側表面である累進面を縦方向と横方向とに分け、横方向についてのみ遠近の表面屈折力差を少なくすることで、上述の問題を回避することができるのである。 That is, it has been found that reducing the surface refractive power difference in the near and far sides of the progressive surface, which is the object side surface, has an advantage in the lateral direction, but is rather worse in the longitudinal direction. Therefore, in the conventional convex progressive-power lens, the above-mentioned problem is avoided by dividing the progressive surface, which is the object side surface, into a vertical direction and a horizontal direction, and reducing the difference in near-surface surface refractive power only in the horizontal direction. It can be done.

これらのことは、次に述べるように、一般にレンズの眼球側である裏面累進（または凹面累進）の長所とされている「視界が広がる」ということについても全く同様である。
一般に「累進面」の側方部には非点収差が存在しているため、水平方向の良好な視界に限界のあることが知られている。そこで、「累進面」を眼球側表面に配置すれば「累進面」そのものが眼に近付くことになり、良好な視界が水平方向に広がるという利点が生ずる。ところが垂直方向においては、逆に遠近の視野領域が遠のく結果となり、眼球を、遠方視から近方視へと回旋させる際の労力が増すという不都合が生ずる。即ち、裏面累進（または凹面累進）は、従来の表面累進（または凸面累進）に比べて、水平方向には視界が広がるという利点があるが、垂直方向には遠方視から近方視に至る際の眼球回旋角が増すと
いう欠点がある。 The same applies to the fact that “the field of view expands”, which is generally regarded as an advantage of back surface progression (or concave surface progression) that is the eyeball side of the lens, as described below.
In general, astigmatism is present in the side portion of the “progressive surface”, and it is known that there is a limit to a good field of view in the horizontal direction. Therefore, if the “progressive surface” is arranged on the eyeball side surface, the “progressive surface” itself approaches the eye, and there is an advantage that a good field of view spreads in the horizontal direction. However, in the vertical direction, on the other hand, the far field of view is far away, resulting in an inconvenience that the labor for rotating the eyeball from far vision to near vision increases. That is, the back surface progression (or concave surface progression) has the advantage that the field of view expands in the horizontal direction compared to the conventional surface progression (or convex surface progression), but in the vertical direction from far vision to near vision. There is a drawback that the eyeball rotation angle increases.

ところが本発明においては前述の如く、ＤＨｆ＋ＤＨｎ＜ＤＶｆ＋ＤＶｎかつＤＨｎ＜ＤＶｎ、または、ＤＶｎ-ＤＶｆ＞ＡＤＤ／２かつＤＨｎ-ＤＨｆ＜ＡＤＤ／２となる関係式を満足させる累進屈折力表面を備えているので、水平方向には従来の表面累進（または凸面累進）の特徴よりも裏面累進（または凹面累進）の特徴が強く、垂直方向には裏面累進（または凹面累進）の特徴よりも従来の表面累進（または凸面累進）の特徴が強いことになる。従って本発明によれば、水平方向には視界が広がるという利点を享受しながら、垂直方向には遠近の眼球回旋角が増すという欠点を抑えることが出来る。 However, as described above, the present invention has a progressive power surface that satisfies the relational expression DHf + DHn <DVf + DVn and DHn <DVn, or DVn-DVf> ADD / 2 and DHn-DHf <ADD / 2. In the horizontal direction, the back surface progression (or concave surface progression) is stronger than the conventional surface progression (or convex surface progression) feature, and in the vertical direction, the conventional surface progression (or concave surface progression) is stronger than the conventional surface progression (or concave surface progression) feature. (Or convex progression) is strong. Therefore, according to the present invention, while enjoying the advantage that the field of view expands in the horizontal direction, it is possible to suppress the disadvantage that the eyeball rotation angle in the near direction increases in the vertical direction.

特に、後述する実施例１に示すように、ＤＶｎ-ＤＶｆ＝ＡＤＤかつＤＨｎ-ＤＨｆ＝０とすれば、垂直方向においては従来の表面累進（または凸面累進）と同等になり、
かつ、
水平方向においては裏面累進（または凹面累進）と同等になる。従って、この場合には、垂直方向の欠点が回避されながら水平方向の利点が得られるという極めて良好な結果となる。
また、以上のことは、前述の如く遠用部と近用部とにおける像の倍率差を減らし、像の歪みや揺れを改善する上でも有効であり、本発明の効果と言うことが出来る。 In particular, as shown in Example 1 described later, if DVn−DVf = ADD and DHn−DHf = 0, the vertical surface direction is equivalent to the conventional surface progression (or convex surface progression),
And,
In the horizontal direction, this is equivalent to back surface progression (or concave surface progression). Therefore, in this case, a very good result is obtained that the advantage in the horizontal direction can be obtained while the vertical defect is avoided.
In addition, the above is effective in reducing the difference in image magnification between the distance portion and the near portion as described above and improving the distortion and shaking of the image, and can be said to be the effect of the present invention.

以上述べたように、本願発明の最も大きな特徴は、累進屈折力レンズの累進作用について、レンズの縦方向と横方向とに分割した上で、各々の方向に対して最適な表裏２面の分担比率を定め、一枚の両面非球面型累進屈折力レンズを構成していることにある。ここで、レンズの物体側表面の縦方向の累進作用の分担比率及び眼球側表面の横方向の累進作用の分担比率は、少なくとも５０％を超える形態で設定することができる。例えば、縦方向の累進作用は全てレンズの物体側表面で与え、横方向の累進作用は全てレンズの眼球側表面で与えるとする分担比率を設定することもできる。 As described above, the greatest feature of the present invention is that the progressive action of the progressive addition lens is divided into the vertical direction and the horizontal direction of the lens, and the optimal two sides of the front and back are divided in each direction. The ratio is determined and one double-sided aspherical progressive-power lens is formed. Here, the ratio of the longitudinal progressive action on the object side surface of the lens and the ratio of the lateral progressive action on the eyeball side surface can be set in a form exceeding at least 50%. For example, it is possible to set a sharing ratio in which all the progressive action in the vertical direction is given from the object side surface of the lens and all the progressive action in the horizontal direction is given from the eyeball side surface of the lens.

この構成を採る場合、レンズの表裏２面のいずれも片面だけでは、通常の累進面として機能せず、累進面としての加入度数を特定することが出来ないことになる。そして、その面に対して処方に従って乱視面などを合成する。
これに対し前述の様々な先行技術は、いずれも加入度数の分担比率に違いはあるものの、レンズの表裏で、まず累進面として必要な加入度数の「値」を表裏２面にそれぞれ割り当て、各々の加入度数を与える実質的な累進面を想定した上で、必要に応じて乱視面などとの合成面を構成している。即ち、レンズの物体側表面及び眼球側表面で、累進作用を縦方向、横方向に分離して設定する構成を有していない。 In the case of adopting this configuration, if both of the front and back surfaces of the lens are only one side, it does not function as a normal progressive surface, and the addition power as the progressive surface cannot be specified. Then, an astigmatic surface or the like is synthesized on the surface according to the prescription.
On the other hand, although the various prior arts mentioned above all have a difference in the share of addition power, the front and back surfaces of the lens first assign a value of addition power required as a progressive surface to the front and back surfaces, respectively. Assuming a substantive progressive surface that gives the addition power, a composite surface with an astigmatism surface or the like is formed as necessary. That is, there is no configuration in which the progressive action is set separately in the vertical direction and the horizontal direction on the object side surface and the eyeball side surface of the lens.

以上のように、本願発明に係るレンズは、縦横両方向により異なる累進作用を有した非球面を、両面に用いるという全く新規な構成を有する両面非球面型累進屈折力レンズである。 As described above, the lens according to the present invention is a double-sided aspherical progressive-power lens having a completely new configuration in which an aspherical surface having a progressive action different in both the vertical and horizontal directions is used on both sides.

［本発明に係る両面非球面型累進屈折力レンズ］
以下、本願発明の実施の形態にかかる両面非球面累進屈折レンズを説明する。
（レンズ設計の手順）
両面非球面累進屈折レンズの光学設計方法の概略の手順は、種々の手順を採用できるが、例えば、以下の方法を用いることができる。
[1]レンズ設計のための入力情報の設定。
[2]凸累進屈折力レンズとしてのレンズの両面設計。
[3]本願発明に係る凸面形状への転換と、それに伴うレンズの裏面補正。
[4]透過設計、リスティング則対応設計などに伴うレンズの裏面補正。
以下、個々の手順をさらに細かいステップに分解して詳述する。 [Double-sided aspherical progressive-power lens according to the present invention]
Hereinafter, a double-sided aspherical progressive refraction lens according to an embodiment of the present invention will be described.
(Lens design procedure)
Various procedures can be adopted as the general procedure of the optical design method of the double-sided aspherical progressive addition lens. For example, the following method can be used.
[1] Input information setting for lens design.
[2] Double-sided design of the lens as a convex progressive power lens.
[3] Conversion to a convex shape according to the invention of the present application, and accompanying lens back surface correction.
[4] Correction of the back side of the lens due to transmission design and listing rule design.
Hereinafter, each procedure will be described in detail by breaking it down into smaller steps.

（[1]レンズ設計のための入力情報の設定）
レンズ設計において、所定の累進屈折力眼鏡レンズを定義するための入力情報を設定する。ここでは、入力情報を、下記のアイテム固有情報と装用者固有情報との２種類に大別して説明する。（尚、光学設計以外のファクターは省略する。）
[1]−１：アイテム固有情報
レンズアイテムに固有のデータである。素材の屈折率Ｎｅ、最小中心肉厚ＣＴｍｉｎ、最小コバ厚ＥＴｍｉｎ、累進面設計パラメータなどのレンズ物性・形状ファクターに関するデータである。
[1]−２：装用者固有情報
遠用度数（球面度数Ｓ、乱視度数Ｃ、乱視軸ＡＸ、プリズム度数Ｐ、プリズム基底方向ＰＡＸなど）、加入度数ＡＤＤ、フレーム形状データ（３次元形状データが望ましい）、フレーム装用データ（前傾角、あおり角など）、頂点間距離、レイアウトデータ（遠用ＰＤ、近用ＣＤ、アイポイント位置など）、その他、眼球に関するデータなどの処方・装用状態・レンズ・フレームに関するファクターのデータである。
なお、装用者から指定される累進帯長や加入度数測定方法、近用部内寄せ量などの累進面設計パラメータは装用者固有情報側に分類している。 ([1] Setting input information for lens design)
In lens design, input information for defining a predetermined progressive-power spectacle lens is set. Here, the input information is broadly divided into the following two types of item specific information and wearer specific information. (Factors other than optical design are omitted.)
[1] -1: Item specific information Data specific to a lens item. This is data relating to lens physical properties and shape factors such as a refractive index Ne of a material, a minimum center thickness CTmin, a minimum edge thickness ETmin, and a progressive surface design parameter.
[1] -2: Wearer-specific information Distance power (spherical power S, astigmatism power C, astigmatism axis AX, prism power P, prism base direction PAX, etc.), addition power ADD, frame shape data (three-dimensional shape data is Desirable), frame wear data (forward tilt, tilt angle, etc.), distance between vertices, layout data (distance PD, near-field CD, eye point position, etc.), and other data related to the eyeball etc. This is factor data regarding the frame.
The progressive surface design parameters such as the progressive zone length, addition power measurement method, and near-site inset amount specified by the wearer are classified on the wearer-specific information side.

（[2]凸累進屈折力レンズとしてのレンズの両面設計）
最初の段階では、従来型の凸累進屈折力レンズとして凸面と凹面とに分けて設計する。
[2]−１：凸面形状（凸累進面）設計
入力情報として与えられた加入度数ＡＤＤや累進帯長を実現するために、入力情報である累進面設計パラメータに従って従来型の凸累進の面形状を設計する。このステップにおける設計では従来の様々なレンズ設計方法を利用することが可能である。 ([2] Double-sided lens design as a convex progressive-power lens)
In the first stage, a conventional convex progressive addition lens is designed with a convex surface and a concave surface.
[2] -1: Convex shape (convex progressive surface) design In order to realize the addition power ADD and progressive band length given as input information, the surface shape of the conventional convex progression according to the progressive surface design parameters as input information To design. Various conventional lens design methods can be used for the design in this step.

このレンズ設計方法の具体例として、例えば、まず最初にレンズ面を構成する際、レンズの背骨にあたる「主子午線」を設定する方法がある。この「主子午線」は最終的には眼鏡装用者が正面上方（遠方）から下方（近方）まで両眼視したときの視線とレンズ面との交線にあたる「主注視線」とすることが好ましい。ただし、近方視における眼の輻湊作用に対応した近方領域の内寄せなどの対応は、後述するように必ずしもこの「主注視線」の内寄せ配置にて行う必要はない。従って、ここでの「主注視線」はレンズ中央を通過し、レンズ面を左右に分割する縦方向の一本の子午線（主子午線）として定義する。さらにレ
ンズは表裏２面あるので、この「主子午線」もまた表裏２本存在することになる。この「主子午線」はレンズ面に対して垂直に眺めると直線状に見えるが、レンズ面が曲面である場合、一般に３次元空間において曲線となる。 As a specific example of this lens design method, for example, there is a method of setting a “main meridian” corresponding to the backbone of the lens when the lens surface is first configured. This “main meridian” will ultimately be the “main gaze”, which is the intersection of the line of sight and the lens surface when the spectacle wearer sees both eyes from the front upper (far) to the lower (near). preferable. However, it is not always necessary to perform the alignment of the near region corresponding to the eye convergence effect in the near vision by the alignment of the “main line of sight” as described later. Accordingly, the “main line of sight” here is defined as a single meridian (main meridian) in the vertical direction that passes through the center of the lens and divides the lens surface into left and right. Furthermore, since there are two front and back lenses, there are also two “main meridians”. This “principal meridian” looks straight when viewed perpendicular to the lens surface, but when the lens surface is a curved surface, it is generally a curve in a three-dimensional space.

次に、所定の加入度数や累進帯の長さなどの情報をもとに、この「主子午線」に沿った適切な屈折力分布を設定する。この屈折力分布は、レンズの厚みや視線と屈折面との角度などの影響を考慮して、表裏２面に分割設定することも可能であるが、このステップにおける設計では従来型の凸累進の面形状を設計する方法を採用しているので、累進作用は全て物体側表面である第１の屈折表面にあるものとする。
従って、例えばレンズの表面（物体側表面である第１の屈折表面）の表面屈折力をＤ１とし、レンズの裏面（眼球側表面である第２の屈折表面）の表面屈折力をＤ２としたとき、得られる透過屈折力をＤとすると、一般にＤ≒Ｄ１−Ｄ２、として近似的に求めることができる。ただし、Ｄ１とＤ２との組み合わせは、当該レンズにおいて、物体側表面が凸であり、眼球側表面が凹であるメニスカス形状であることが望ましい。
尚、ここで、Ｄ２は正の値であるとしている。通常、レンズの裏面は凹面であり、表面屈折力としては負の値となるが、本明細書では説明の簡素化の為、正の値とし、Ｄ１からＤ２を減じて透過屈折力Ｄを算出する。 Next, an appropriate refractive power distribution along the “main meridian” is set based on information such as a predetermined addition power and the length of the progressive zone. This refractive power distribution can be divided into two front and back surfaces in consideration of the influence of the lens thickness and the angle between the line of sight and the refracting surface. Since the method of designing the surface shape is adopted, it is assumed that all the progressive actions are on the first refractive surface which is the object side surface.
Therefore, for example, when the surface refractive power of the lens surface (the first refractive surface that is the object-side surface) is D1, and the surface refractive power of the rear surface of the lens (the second refractive surface that is the eyeball-side surface) is D2. If the transmission power obtained is D, it can be approximately obtained as D≈D1−D2. However, it is desirable that the combination of D1 and D2 has a meniscus shape in which the object side surface is convex and the eyeball side surface is concave.
Here, D2 is assumed to be a positive value. Normally, the back surface of the lens is concave, and the surface refractive power has a negative value. However, in this specification, for simplicity of explanation, a positive value is used, and the transmission refractive power D is calculated by subtracting D2 from D1. To do.

この表面屈折力と表面形状との関係式については一般に次の式で定義される
Ｄｎ＝（Ｎ−１）／Ｒ
ここに、Ｄｎ：第ｎ面の表面屈折力（単位：ジオプター）、Ｎ：レンズ素材の屈折率、Ｒ：曲率半径（単位：ｍ）である。従って、表面屈折力の分布を曲率の分布に換算する方法は、上記の関係式を変形した、
１／Ｒ＝Ｄｎ／（Ｎ−１）
を用いる。曲率の分布が得られたことにより、「主子午線」の幾何学的形状が一義的に確定し、レンズ面を構成する際の背骨にあたる「主子午線」が設定されることになる。 The relational expression between the surface refractive power and the surface shape is generally defined by the following formula: Dn = (N−1) / R
Here, Dn is the surface refractive power (unit: diopter) of the nth surface, N is the refractive index of the lens material, and R is the radius of curvature (unit: m). Therefore, the method for converting the surface refractive power distribution into the curvature distribution is a modification of the above relational expression.
1 / R = Dn / (N-1)
Is used. By obtaining the distribution of curvature, the geometric shape of the “main meridian” is uniquely determined, and the “main meridian” corresponding to the backbone when the lens surface is constructed is set.

次に、必要となるのは、レンズ面を構成する際の肋骨にあたる「水平方向の断面曲線群」の設計である。これらの「水平方向の断面曲線群」と「主子午線」とが交わる角度は必ずしも直角である必要は無いが、説明を簡単にする為に、ここでは各々の「水平方向の断面曲線」は「主子午線」上で直角に交わるものとする。さらに「主子午線」との交点における「水平方向の断面曲線群」の「横方向の表面屈折力」もまた、必ずしも「主子午線」に沿った「縦方向の表面屈折力」と等しい必要はないが、本実施例ではこれらの交点における縦方向と横方向の表面屈折力は等しいものとする。 Next, what is needed is a design of a “horizontal cross-sectional curve group” that corresponds to the ribs when forming the lens surface. The angle at which these “horizontal cross section curve group” and “main meridian” intersect is not necessarily a right angle, but for the sake of simplicity, each “horizontal cross section curve” is “ It shall intersect at right angles on the “main meridian”. Furthermore, the “lateral surface power” of the “horizontal section curve group” at the intersection with the “main meridian” does not necessarily need to be equal to the “vertical surface power” along the “main meridian”. However, in this embodiment, the surface refractive powers in the vertical direction and the horizontal direction at these intersections are assumed to be equal.

全ての「水平方向の断面曲線」はこれらの交点における表面屈折力を有する単純な円形曲線とすることも出来るが、様々な従来技術を組込んだ応用も可能である。「水平方向の断面曲線」に沿った表面屈折力分布に関する従来技術例として、例えば、特公昭４９−３５９５の技術がある。これはレンズの中央近傍に一本のほぼ円形形状の「水平方向の断面曲線」を設定し、それより上方に位置する断面曲線は中央から側方にかけて増加する表面屈折力分布を有し、下方に位置する断面曲線は中央から側方にかけて減少する表面屈折力分布を有することを特徴としている。このように、「主子午線」と、その上に無数に並ん
だ「水平方向の断面曲線群」が、あたかも背骨と肋骨の如くレンズ面を構成することになり、屈折面が確定する。 All “horizontal cross-sectional curves” can be simple circular curves with surface power at these intersections, but applications incorporating various conventional techniques are also possible. As a prior art example regarding the surface refractive power distribution along the “horizontal cross section curve”, for example, there is a technique disclosed in Japanese Patent Publication No. 49-3595. This sets a single “circular cross-sectional curve” in the vicinity of the center of the lens, and the cross-sectional curve located above it has a surface refractive power distribution that increases from the center to the side, The cross-sectional curve located at is characterized by having a surface refractive power distribution that decreases from the center to the side. In this way, the “main meridian” and the “horizontal cross-sectional curve group” arranged innumerably thereon constitute a lens surface as if it were a spine and a rib, and the refractive surface is determined.

[2]−２：凹面形状（球面または乱視面）設計
入力情報として与えられた遠用度数を実現するために、凹面形状を設計する。
遠用度数に乱視度数があれば乱視面となり、無ければ球面となる。このとき、度数に適した中心肉厚ＣＴや凸面と凹面との面相互の傾斜角も同時に設計し、レンズとしての形状を確定する。このステップにおける設計も従来の様々な公知の設計技術を利用することが可能である。 [2] -2: Concave surface shape (spherical surface or astigmatic surface) design Concave surface shape is designed to realize the distance dioptric power given as input information.
If the distance power has an astigmatism power, an astigmatism surface is obtained. At this time, the center thickness CT suitable for the power and the inclination angle between the convex and concave surfaces are also designed at the same time, and the shape as a lens is determined. The design in this step can also use various conventional known design techniques.

（[3]本願発明の凸面形状への転換とそれに伴うレンズの裏面補正）
入力情報として与えられた遠用度数や加入度数ＡＤＤなどに応じ、従来型の凸累進屈折力レンズから本願発明のレンズとしての形状に転換する。
[3]−１：凸面形状（本願発明）設計
入力情報として与えられた遠用度数や加入度数ＡＤＤなどに応じ、従来型の凸累進面から本願発明の凸面形状に転換する。この時、予めレンズの縦方向と横方向とに分割した上で、各々の方向に対して好ましい表裏２面の分担比率を設定しておく。即ち、前述の第１の凸累進のレンズの表面（物体側表面である第１の屈折表面）において、遠用度数測定位置Ｆ１における、横方向の表面屈折力をＤＨｆ、縦方向の表面屈折力をＤＶｆ、近用度数測定位置Ｎ１における、横方向の表面屈折力をＤＨｎ、縦方向の表面屈折力をＤＶｎとするとき、
ＤＨｆ＋ＤＨｎ＜ＤＶｆ＋ＤＶｎ
かつＤＨｎ＜ＤＶｎ
となる関係式を満足させるか、更に、
ＤＶｎ−ＤＶｆ＞ＡＤＤ／２
かつＤＨｎ−ＤＨｆ＜ＡＤＤ／２
となる関係式を満足させる屈折力表面とする。
本実施態様では両者を満足するものとして設定する。 ([3] Conversion to the convex shape of the present invention and accompanying lens back surface correction)
According to the distance power or addition power ADD given as input information, the conventional convex progressive addition lens is changed to the shape of the lens of the present invention.
[3] -1: Convex shape (invention of the present invention) design The conventional convex progressive surface is changed to the convex shape of the present invention in accordance with the distance power or addition power ADD given as input information. At this time, after dividing into the vertical direction and the horizontal direction of the lens in advance, a preferred ratio of the front and back two surfaces is set for each direction. That is, on the surface of the first convex progressive lens (the first refractive surface that is the object-side surface), the horizontal surface refractive power is DHf and the vertical surface refractive power at the distance power measurement position F1. Is DVf, and the near surface power measurement position N1 has a horizontal surface power DHn and a vertical surface power DVn.
DHf + DHn <DVf + DVn
And DHn <DVn
Or satisfy the relational expression
DVn-DVf> ADD / 2
And DHn-DHf <ADD / 2
The refractive power surface satisfies the following relational expression.
In this embodiment, both are set to satisfy.

このとき、凸面全体の平均的な表面屈折力は変えないで、本願発明の凸面形状に変換することが好ましい。具体的には、例えば、遠用部と近用部との縦横の表面屈折力の総平均値を維持することなどが考えられる。ただし、当該レンズにおいて、物体側表面が凸であり、眼球側表面が凹であるメニスカス形状を保つ範囲内であることが好ましい。 At this time, it is preferable to convert the average surface refractive power of the entire convex surface into the convex shape of the present invention without changing it. Specifically, for example, it is conceivable to maintain the total average value of the vertical and horizontal surface refractive powers of the distance portion and the near portion. However, the lens preferably has a meniscus shape in which the object-side surface is convex and the eyeball-side surface is concave.

[3]−２：凹面形状（本願発明）設計
上記[3]−１において、従来型の凸累進面から本願発明の凸面形状に転換した際の変形量を、[2]−２で設計した凹面形状に加算する。即ち、[3]−１のプロセスで加えられたレンズの表面（物体側表面である第１の屈折表面）の変形量を、レンズの裏面（眼球側表面である第２の屈折表面）側にも同じ量だけ加えるのである。この変形は、レンズそのものを曲げる所謂「ベンディング」と似ているが、レンズ全面に渉る均一な変形ではなく、[3]−１に記載した関係式を満足させる表面とするものである。 [3] -2: Concave shape (present invention) design In [3] -1, the amount of deformation when the conventional convex progressive surface is converted to the convex shape of the present invention is designed in [2] -2. Add to the concave shape. That is, the deformation amount of the lens surface (the first refractive surface that is the object-side surface) added in the process [3] -1 is transferred to the back surface (second refractive surface that is the eyeball-side surface) side of the lens. Add the same amount. This deformation is similar to so-called “bending” in which the lens itself is bent, but it is not a uniform deformation over the entire surface of the lens but a surface that satisfies the relational expression described in [3] -1.

尚、レンズの処方や仕様によっては、このステップで発明が完成する場合もある。しかし、好ましくは、前記の補正を一次近似的な補正として取り扱い、更に、次の、[4]の裏面補正ステップを加えることが好ましい。 Depending on the prescription and specifications of the lens, the invention may be completed at this step. However, it is preferable to treat the correction as a first-order approximate correction, and to add the following back surface correction step [4].

（[4]透過設計、リスティング則対応設計などに伴うレンズの裏面補正）
入力情報としてレンズに課せられた光学的な機能を、装用者が実際にレンズを装用した状況において実現するために、[3]において得られた本願発明に係るレンズに対して、更に裏面補正を加えることが好ましい。
[4]−１：透過設計による凹面形状（本願発明）設計
透過設計とは、装用者がレンズを実際に装用した状況において本来の光学的な機能を得るための設計方法であり、主として視線とレンズ面とが直交しえないことに起因する非点収差の発生や度数の変化を、除去もしくは低減するための「補正作用」を加える設計方法である。 ([4] Lens backside correction for transmission design, listing rule design, etc.)
In order to realize the optical function imposed on the lens as input information in a situation where the wearer actually wears the lens, the back surface correction is further performed on the lens according to the present invention obtained in [3]. It is preferable to add.
[4] -1: Concave surface shape design by transmission design (present invention) Transmission design is a design method for obtaining an original optical function in a situation where a wearer actually wears a lens. This is a design method for adding a “correcting action” for removing or reducing the generation of astigmatism and the change in power caused by the fact that the lens surface cannot be orthogonal.

具体的には、前述の如く、視線の方向に応じた厳密な光線追跡計算によって、目的である本来の光学性能との差異を把握し、その差異を打ち消す面補正（カーブ補正）を実施する。これを繰返すことにより差異を極小化させ、最適な解を得ることが出来る。
一般に、目標とする光学性能を有するレンズ形状を直接算出することは極めて困難であり、事実上不可能であることが多い。これは「任意に設定した光学性能を有するレンズ形状」が、実在するとは限らないからである。ところが、これとは逆に「任意に設定したレ
ンズ形状の光学性能」を求めることは比較的容易である。従って、最初に任意の方法で第一次近似の面を仮計算し、その近似面を用いたレンズ形状の光学性能の評価結果に応じて前記設計パラメータを微調整し、次に、レンズ形状を逐次変更して評価ステップに戻り、再評価と再調整を繰り返して目標とする光学性能へ近付けることが可能である。この手法は「最適化」と呼ばれて広く知られている手法の一例である。 More specifically, as described above, the surface correction (curve correction) is performed to grasp the difference from the target original optical performance by strict ray tracing calculation according to the direction of the line of sight and to cancel the difference. By repeating this, the difference can be minimized and an optimal solution can be obtained.
In general, it is extremely difficult and often impossible to directly calculate a lens shape having a target optical performance. This is because the “lens shape having arbitrarily set optical performance” does not always exist. However, on the contrary, it is relatively easy to obtain “an optical performance of an arbitrarily set lens shape”. Therefore, the surface of the first approximation is temporarily calculated by an arbitrary method, the design parameters are finely adjusted according to the evaluation result of the optical performance of the lens shape using the approximation surface, and then the lens shape is changed. It is possible to gradually change and return to the evaluation step, and repeat reevaluation and readjustment to approach the target optical performance. This method is an example of a widely known method called “optimization”.

[4]−２：リスティング則対応設計のための凹面形状（本願発明）設計
我々が周囲を見渡すときの眼球の３次元的な回旋運動は、「リスティング則」と呼ばれる規則に則っていることが知られているが、レンズの処方度数に乱視度数がある場合、眼鏡レンズの乱視軸を「正面視での眼球の乱視軸」に合わせたとしても、周辺視をした場合には双方の乱視軸が一致しない場合がある。このように周辺視におけるレンズと眼との乱視軸方向が一致しないことに起因する非点収差の発生や、度数の変化を、除去もしくは低減するための「補正作用」を、本発明に係るレンズの乱視矯正作用を有する側の表面の曲面に加えることが出来る。 [4] -2: Concave surface shape design for the design corresponding to the listing rule (the invention of the present application) The three-dimensional rotational movement of the eyeball when we look around is based on a rule called “listing rule” As is known, when the prescription power of the lens has an astigmatism power, even if the astigmatism axis of the spectacle lens is aligned with the `` astigmatism axis of the eyeball in frontal view '', both astigmatism axes in peripheral vision May not match. As described above, the lens according to the present invention has the “correcting action” for removing or reducing the generation of astigmatism and the change in the power due to the astigmatic axis directions of the lens and the eye in peripheral vision not matching. It can be added to the curved surface of the surface having the astigmatism correction function.

具体的に、「補正作用」を本発明に係るレンズの曲面に加えるには、[4]−１で用いた「最適化」の方法と同様で、視線の方向に応じた厳密な光線追跡計算によって、目的である本来の光学性能との差異を把握し、その差異を打ち消す面補正を実施する。この操作を繰返すことにより差異を極小化させ、最適な解を得ることが出来る。 Specifically, in order to add the “correction action” to the curved surface of the lens according to the present invention, as in the “optimization” method used in [4] -1, exact ray tracing calculation according to the direction of the line of sight Thus, the difference from the target original optical performance is grasped, and surface correction is performed to cancel the difference. By repeating this operation, the difference can be minimized and an optimal solution can be obtained.

[4]−３：近用部の内寄せ対応設計のための凹面形状（本願発明）設計
上述した内寄せ方法として、本実施例では、図1及び図5−１の累進屈折力眼鏡レンズの光学的レイアウトの説明図に示すように、主子午線（M）を遠用度数測定位置（F）から近用度数測定位置（N）にかけて鼻側に変位させた設計手法を採用している。この設計手法は、眼の輻輳を考慮した方法であり、輻輳作用に基づく主子午線の鼻側への変位量は、次の式に基づいて設定されている。
変位量（H）≒A×D+B
ここで、Hは主子午線（M）上の遠用度数測定位置（F）に対しの鼻側への変位量、Dは付加屈折力（加入度数ADD）、Aは比例定数、Bは定数（0も含む）である。 [4] -3: Concave shape (invention of the present application) design for near-centering corresponding design In the present embodiment, in the present embodiment, the progressive-power spectacle lens of FIGS. As shown in the explanatory diagram of the optical layout, a design method is adopted in which the main meridian (M) is displaced to the nose side from the distance power measurement position (F) to the near power measurement position (N). This design method is a method that considers eye convergence, and the amount of displacement of the main meridian to the nose side based on the convergence action is set based on the following equation.
Displacement (H) ≒ A × D + B
Here, H is the displacement to the nasal side relative to the distance power measurement position (F) on the main meridian (M), D is the additional refractive power (add power ADD), A is a proportional constant, B is a constant ( (Including 0).

ここで具体的な変位量の値は、レンズの処方や加入度数により異なり、任意に設定できるが、例えば以下の方法が採用できる。
図5−1において、上記点Fを原点として、右方をH座標軸（水平方向変位量）、下方をV座標軸（垂直方向）の座標系を想定した場合、近用度数測定位置（N）のH座標、V座標をそれぞれH_MAX、V_MAXとし、その加入度数をD_MAXとする。すると、例えば、具体的に加入度数D_MAXを３.００、変位量を2.5mm（この場合、B=０を採用）、Vを12mmに設定しておいて、その、遠用度数測定位置（F）から近用度数測定位置（N）の子午線（M）の各点の変位量をVの座標ごとに設定していくことにより達成できる。（例えば、特公昭62-47284号参照）無論、眼の輻輳作用に基づく主子午線（主注視線）の配置は上記の式のみに限定されず、輻輳量の調整や他のファクターを加味したりすることもできる。 Here, the specific value of the amount of displacement differs depending on the prescription and addition power of the lens and can be arbitrarily set. For example, the following method can be adopted.
In Fig. 5-1, assuming a coordinate system with the point F as the origin, the H coordinate axis (horizontal displacement) on the right side, and the V coordinate axis (vertical direction) on the lower side, the near frequency measurement position (N) The H coordinate and V coordinate are H _MAX and V _MAX , respectively, and the addition power is D _MAX . Then, for example, the addition power D _MAX is specifically set to 3.00, the displacement is set to 2.5 mm (in this case, B = 0 is adopted), V is set to 12 mm, and the distance power measurement position ( This can be achieved by setting the displacement amount of each point on the meridian (M) at the near power measurement position (N) from F) for each V coordinate. (For example, refer to Japanese Examined Patent Publication No. 62-47284) Of course, the arrangement of the main meridian (main gaze) based on the vergence of the eye is not limited to the above formula, and the adjustment of the amount of convergence and other factors are taken into account. You can also

また、レンズの加工方法において、本発明は両面非球面という面構成を採っているが、だからといって必ずしも受注してから、両面の加工を開始する必要はない。例えば本発明の目的にかなう物体側表面の「半完成品（セミフィニッシュレンズ或いは省略してセミレンズともいう）」をあらかじめ準備しておく方法を採ることができる。そして、受注後に処方度数や上述のカスタムメイド（個別設計）などの仕様に応じて前記の「物体側表面の半完成品」を選択し、眼球側表面のみを受注後に加工して仕上げることで、コスト軽減と加工スピードをアップすることができる。 Further, in the lens processing method, the present invention adopts a double-sided aspherical surface configuration, but it is not always necessary to start processing on both sides after receiving an order. For example, it is possible to adopt a method in which a “semi-finished product (also referred to as semi-finished lens or abbreviated as semi-lens)” on the object side surface that meets the object of the present invention is prepared in advance. And after selecting an order, select the “semi-finished product on the object side surface” according to the specifications such as the prescription frequency and the above-mentioned custom-made (individual design), and processing and finishing only the eyeball side surface after receiving the order. Cost reduction and processing speed can be increased.

この方法の具体例として、例えば前述[3]−１の凸面形状（本願発明）設計において物体側表面を左右対称の「半完成品」としてあらかじめ準備しておく方法を採ることができる。即ち、ここでは、主子午線（＝主注視線）は直線であり、屈折表面の非点収差の分布は主子午線を境に左右対称設計となっており、眼の輻輳を考慮した主子午線となっていない。（後述する図４１参照）従って、左眼用、右眼用として別々にセミレンズを用意する必要がないので、加工や在庫管理が容易になる。そして、瞳孔間距離や近方視の対物距離、加入度数などの個人情報が入力されてから、当該レンズの眼球側表面を目的にかなった左右非対称な曲面設計（累進部・近用部の屈折表面の非点収差の分布が主子午線を境として非対称）することにより、個人情報に対応した近用部の内寄せを行なうことが出来る。 As a specific example of this method, for example, in the above-mentioned [3] -1 convex shape design (the present invention) design, a method can be adopted in which the object side surface is prepared in advance as a symmetric “semi-finished product”. That is, here, the main meridian (= main line of sight) is a straight line, and the distribution of astigmatism on the refractive surface is symmetrical with respect to the main meridian, which is the main meridian considering eye convergence. Not. Therefore, since it is not necessary to prepare semi-lenses separately for the left eye and the right eye, processing and inventory management are facilitated. Then, after personal information such as interpupillary distance, near-distance objective distance, and addition power is input, the left and right asymmetric curved surface design (progression and near-field refraction is used). Since the astigmatism distribution on the surface is asymmetrical with respect to the main meridian, the near portion corresponding to the personal information can be aligned.

以下、上述の設計方法によって設計した両面非球面累進屈折レンズの実施例を、図面を参照しながら説明する。
図７は、実施例１、４、５、６と各々の度数に対応した従来技術Ａ，Ｂ，Ｃの「表面屈折力」と「特定の視線方向に対する厳密な倍率計算結果」を表１−１及び表１−２にまとめて示した表、図８は、実施例２、７と各々の度数に対応した従来技術Ａ，Ｂ，Ｃの「表面屈折力」と「特定の視線方向に対する厳密な倍率計算結果」を表２−１及び表２−２にまとめて示した表、図９は、実施例３とその度数に対応した従来技術Ａ，Ｂ，Ｃの「表面屈折力」と「特定の視線方向に対する厳密な倍率計算結果」を表３−１及び表３−２にまとめて示した表、図１０、は実施例１及び実施例２の表面屈折力分布を表すグラフ１−１
、１−２、２−１、２−２を示すグラフ、図１１は、実施例３の表面屈折力分布を表すグラフ３−１、３−２を示すグラフ、図１２は、実施例４〜６の表面屈折力分布を表すグラフ４−１、４−２、５−１、５−２、６−１、６−２を示すグラフ、図１３は、実施例７の表面屈折力分布を表すグラフ７−１、７−２を示すグラフ、図１４、は従来技術例Ａ，Ｂ，Ｃの表面屈折力分布を表すグラフＡ−１、Ａ−２、Ｂ−１、Ｂ−２、Ｃ−１、Ｃ−２を示すグラフである。 Hereinafter, embodiments of a double-sided aspherical progressive refraction lens designed by the above-described design method will be described with reference to the drawings.
FIG. 7 shows the “surface refractive power” and “strict magnification calculation result for a specific line-of-sight direction” of the conventional techniques A, B, and C corresponding to Examples 1, 4, 5, and 6, respectively. FIG. 8 is a table collectively shown in Table 1 and Table 1-2. FIG. 8 shows the “surface refractive power” and “strict strictness with respect to a specific line-of-sight direction” in the conventional techniques A, B, and C corresponding to Examples 2 and 7 and respective frequencies. Table 2-1 and Table 2-2 collectively showing “magnification result of magnification”, FIG. 9 shows “surface refractive power” and “surface refractive power” of conventional techniques A, B, and C corresponding to Example 3 and the frequency thereof. Table 3-1 and Table 3-2 collectively showing "strict magnification calculation results for specific gaze direction", FIG. 10 is a graph 1-1 showing surface refractive power distribution of Example 1 and Example 2
FIG. 11 is a graph showing the surface refractive power distribution of Example 3; and FIG. 12 is a graph showing Examples 3-1 and 2-2. FIG. 13 shows the surface refractive power distribution of Example 7, which is a graph showing the surface refractive power distribution 6 of FIG. Graphs 7-1 and 7-2 and FIG. 14 are graphs A-1, A-2, B-1, B-2, and C- showing surface refractive power distributions of the related art examples A, B, and C, respectively. 1 is a graph showing C-2.

図１５は、実施例１とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ１−３−Ｍｓｖを示し、図１６は、実施例１とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ１−３−Ｍｓｈを示す、図１７は、実施例１とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ１−３−Ｍｐｖを示す、図１８は、実施例１とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ１−３−Ｍｐｈを示す、図１９は、実施例１とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めた
ときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ１−３−Ｍγｖを示す、図２０は、実施例１とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ１−３−Ｍγｈを示す、図２１は、実施例１とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ１−３−ＳＭｖを示す、図２２は、実施例１とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ１−３−ＳＭｈを示す。 FIG. 15 shows the result obtained by carrying out a strict magnification calculation for the magnification distribution when viewing the lenses of Example 1 and three types of conventional examples A, B, and C corresponding to the power along the main line of sight. Graph 1-3-3-Msv is shown, and FIG. 16 shows the magnification distribution when the lenses of Example 1 and three types of conventional examples A, B, and C corresponding to the frequency are viewed along the main line of sight. FIG. 17 shows a graph 1-3-3-Msh representing the result obtained by performing various magnification calculations. FIG. 17 shows the lenses of Example 1 and three types of conventional examples A, B, and C corresponding to the frequency as the main line of sight. FIG. 18 shows a graph 1-3-3-Mpv showing the result obtained by performing a strict magnification calculation of the magnification distribution when viewed along the line. FIG. 18 shows three types of conventional examples A, A corresponding to Example 1 and its frequency. The magnification distribution when the B and C lenses were viewed along the main line of sight was obtained by performing a strict magnification calculation. FIG. 19 shows a graph 1-3-Mph representing the results. FIG. 19 shows a magnification distribution when the lenses of Example 1 and three types of conventional examples A, B, and C corresponding to the frequency are viewed along the main line of sight. FIG. 20 shows a graph 1-3-3-Mγv representing the result obtained by performing a strict magnification calculation of FIG. 20, and FIG. 20 mainly focuses on the lenses of Example 1 and three conventional examples A, B, and C corresponding to the frequency. FIG. 21 shows a graph 1-3-Mγh representing the result obtained by performing a strict magnification calculation of the magnification distribution when viewed along the line of sight. FIG. 21 shows Example 1 and three types of conventional examples corresponding to the frequency. FIG. 22 shows a graph 1-3-3-SMv showing the result obtained by performing a strict magnification calculation on the magnification distribution when the lenses A, B, and C are viewed along the main gazing line. Double of the three conventional lenses A, B, and C corresponding to the power when viewed along the main line of sight Distribution shows a graph 1-3-SMh representing results obtained by performing the accurate magnification calculations.

図２３は、実施例２とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ２−３−Ｍｓｖを示す、図２４は、実施例２とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ２−３−Ｍｓｈを示す、図２５は、実施例２とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ２−３−Ｍｐｖを示す、図２６は、実施例２とその度数に
対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ２−３−Ｍｐｈを示す、図２７は、実施例２とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ２−３−Ｍγｖを示す、図２８は、実施例２とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ２−３−Ｍγｈを示す、図２９は、実施例２とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃ
のレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ２−３−ＳＭｖを示す、図３０は、実施例２とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ２−３−ＳＭｈを示す。 FIG. 23 shows the result obtained by carrying out a strict magnification calculation of the magnification distribution when viewing the lenses of Example 2 and three types of conventional examples A, B, and C corresponding to the power along the main line of sight. FIG. 24 showing a graph 2-3-3-Msv represents the magnification distribution when the lenses of Example 2 and three types of conventional examples A, B, and C corresponding to the frequency are viewed along the main line of sight. FIG. 25 shows a graph 2-3-3-Msh representing the result obtained by performing various magnification calculations. FIG. 25 shows the lenses of Example 2 and three types of conventional examples A, B, and C corresponding to the frequency as the main gaze line. FIG. 26 shows a graph 2-3-3-Mpv showing the result obtained by performing a strict magnification calculation of the magnification distribution when viewed along the line. FIG. 26 shows Example 2 and three types of conventional examples A, A corresponding to the frequency. The magnification distribution when the B and C lenses were viewed along the main line of sight was obtained by performing a strict magnification calculation. FIG. 27 shows a graph 2-3-3-Mph representing the results. FIG. 27 shows a magnification distribution when the lenses of the conventional example A, B, and C corresponding to Example 2 and the frequency thereof are viewed along the main gazing line. FIG. 28 shows a graph 2-3-3-Mγv representing the result obtained by performing a strict magnification calculation of FIG. 28. In FIG. FIG. 29 shows a graph 2-3-3-Mγh that represents the result of performing a strict magnification calculation of the magnification distribution when viewed along the line of sight. FIG. 29 shows Example 2 and three types of conventional examples corresponding to the frequency. A, B, C
FIG. 30 shows a graph 2-3-3-SMv that represents a result obtained by performing a strict magnification calculation on a magnification distribution when viewing the lens of the lens along the main gazing line. FIG. 30 corresponds to Example 2 and the frequency thereof. Graph 2-3-3-SMh representing the result of performing a strict magnification calculation on the magnification distribution when viewing the lenses of three types of conventional examples A, B, and C along the main gazing line is shown.

図３１は、実施例３とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ３−３−Ｍｓｖを示す、図３２は、実施例３とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ３−３−Ｍｓｈを示す、図３３は、実施例３とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ３−３−Ｍｐｖを示す、図３４は、実施例３とその度数に
対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ３−３−Ｍｐｈを示す、図３５は、実施例３とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ３−３−Ｍγｖを示す、図３６は、実施例３とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ３−３−Ｍγｈを示す、図３７は、実施例３とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ３−３−ＳＭｖを示す、図３８は、実施例３とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたと
きの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ３−３−ＳＭｈを示す。 FIG. 31 shows the result of strict magnification calculation for the magnification distribution when viewing the lenses of Example 3 and three types of conventional examples A, B, and C corresponding to the frequency along the main line of sight. FIG. 32 showing a graph 3-3-Msv showing the strict magnification distribution when the lenses of Example 3 and three types of conventional examples A, B, and C corresponding to the frequency are viewed along the main line of sight. FIG. 33 shows a graph 3-3-Msh representing the result obtained by performing various magnification calculations. FIG. 33 shows the lenses of Example 3 and three types of conventional examples A, B, and C corresponding to the frequency as the main gaze line. FIG. 34 shows a graph 3-3-Mpv showing a result obtained by performing a strict magnification calculation of the magnification distribution when viewed along the line. FIG. 34 shows Example 3 and three types of conventional examples A, A corresponding to the frequency. The magnification distribution when the B and C lenses were viewed along the main line of sight was obtained by performing a strict magnification calculation. FIG. 35 shows a graph 3-3-Mph representing the results. FIG. 35 shows a magnification distribution when the lenses of Example 3 and three types of conventional examples A, B, and C corresponding to the frequency are viewed along the main line of sight. FIG. 36 shows a graph 3-3-Mγv representing the result obtained by performing a strict magnification calculation of FIG. 36. In FIG. 36, the lenses of Example 3 and three types of conventional examples A, B, and C corresponding to the frequency are mainly used. FIG. 37 shows a graph 3-3-Mγh showing the result of performing a strict magnification calculation of the magnification distribution when viewed along the line of sight. FIG. 37 shows Example 3 and three types of conventional examples corresponding to the frequency. FIG. 38 shows a graph 3-3-SMv representing the result obtained by performing a strict magnification calculation on the magnification distribution when the lenses A, B, and C are viewed along the main gazing line. Double of the three conventional lenses A, B, and C corresponding to the power when viewed along the main line of sight Distribution shows a graph 3-3-SMh representing results obtained by performing the accurate magnification calculations.

（実施例１）
図７の表１−１は、本発明による実施例１の表面屈折力に関する一覧表である。この実施例１のレンズの度数はＳ０．００Ａｄｄ３．００に対応しており、比較のために同度数の３種類の従来技術例を併記してある。なお、従来技術例Ａは物体側表面が累進面である「凸面累進屈折力レンズ」に、従来技術例Ｂは物体側表面と眼球側表面との両方が累進面である「両面累進屈折力レンズ」に、従来技術例Ｃは眼球側表面が累進面である「凹面累進屈折力レンズ」に、それぞれ対応している。また、表１−１で用いた項目の意味は下記の通りである。
ＤＶｆ１：物体側表面の遠用度数測定位置Ｆ１における縦方向の表面屈折力
ＤＨｆ１：物体側表面の遠用度数測定位置Ｆ１における横方向の表面屈折力
ＤＶｎ１：物体側表面の近用度数測定位置Ｎ１における縦方向の表面屈折力
ＤＨｎ１：物体側表面の近用度数測定位置Ｎ１における横方向の表面屈折力
ＤＶｆ２：眼球側表面の遠用度数測定位置Ｆ２における縦方向の表面屈折力
ＤＨｆ２：眼球側表面の遠用度数測定位置Ｆ２における横方向の表面屈折力
ＤＶｎ２：眼球側表面の近用度数測定位置Ｎ２における縦方向の表面屈折力
ＤＨｎ２：眼球側表面の近用度数測定位置Ｎ２における横方向の表面屈折力 Example 1
Table 1-1 in FIG. 7 is a list relating to the surface refractive power of Example 1 according to the present invention. The power of the lens of Example 1 corresponds to S0.00 Add3.00, and three types of prior art examples of the same power are shown for comparison. The conventional example A is a “convex progressive-power lens” in which the object-side surface is a progressive surface, and the conventional example B is “double-sided progressive-power lens in which both the object-side surface and the eyeball-side surface are progressive surfaces. The prior art example C corresponds to a “concave progressive addition lens” whose surface on the eyeball side is a progressive surface. Moreover, the meaning of the item used by Table 1-1 is as follows.
DVf1: Longitudinal surface refractive power at the distance power measurement position F1 on the object side surface DHf1: Horizontal surface power at the distance power measurement position F1 on the object side surface DVn1: Near power measurement position N1 on the object side surface Surface refractive power in the vertical direction at DHn1: Surface refractive power in the horizontal direction at the near power measurement position N1 on the object side surface DVf2: Surface refractive power in the vertical direction at the distance power measurement position F2 on the eyeball side surface DHf2: Surface on the eyeball side Surface refractive power in the lateral direction at the distance power measurement position F2 of the lens DVn2: Surface refractive power in the vertical direction at the near power measurement position N2 on the eyeball side surface DHn2: Surface in the lateral direction at the near power measurement position N2 on the eyeball side surface Refractive power

図１０のグラフ１−１と１−２とは、実施例１のレンズの主注視線に沿った表面屈折力分布を表すグラフであり、横軸はレンズの位置（距離）を表し、右側がレンズ上方、左側がレンズ下方を、また、縦軸は表面屈折力を表す。ここで、グラフ１−１はレンズの物体側表面に対応し、グラフ１−２はレンズの眼球側表面に対応している。また、実線のグラフは、レンズの主注視線に沿った縦方向の表面屈折力分布を表し、点線のグラフは、レンの主注視線に沿った横方向の表面屈折力分布を表す。 Graphs 1-1 and 1-2 in FIG. 10 are graphs representing the surface refractive power distribution along the main gazing line of the lens of Example 1, the horizontal axis represents the position (distance) of the lens, and the right side is the graph. The upper side and the left side of the lens indicate the lower side of the lens, and the vertical axis indicates the surface refractive power. Here, the graph 1-1 corresponds to the object side surface of the lens, and the graph 1-2 corresponds to the eyeball side surface of the lens. The solid line graph represents the surface refractive power distribution in the vertical direction along the main gaze line of the lens, and the dotted line graph represents the surface refractive power distribution in the horizontal direction along the main gaze line of Len.

グラフ１−１において、図が示すように、物体側表面の主注視線に沿った縦方向の表面屈折力分布を表すグラフＣＶ１（実線）は、その屈折力分布が累進帯部〜近用部にかけて変化しているが、横方向の表面屈折力分布を表すグラフＣＨ１（点線）は、変化がない。また、縦方向の表面屈折力分布を表すグラフＣＶ１（実線）と、横方向の表面屈折力分布を表すグラフＣＨ１（点線）とでは累進帯部〜近用部にかけて表面屈折力が異なっている。
この場合、光学的に物体側表面の主注視線上を通過した光線において、ほぼ縦方向と横方向との表面屈折力の差の分だけ非点収差が発生することになる。
一方、グラフ１−２において、図が示すように、眼球側表面の主注視線に沿った縦方向の表面屈折力分布を表すグラフＣＶ２（実線）は、その屈折力分布が遠用部〜累進帯部〜近用部まで変化がない。一方、横方向の表面屈折力分布を表すグラフＣＨ２（点線）は、累進帯部〜近用部にかけて表面屈折力が異なっている。また、この縦方向の表面屈折力分布を表すグラフＣＶ２（実線）と、横方向の表面屈折力分布を表すグラフＣＨ２（点線）との表面屈折力の分布もグラフ１−１と同様、累進帯部〜近用部にかけて異なっている。
ところが、その表面屈折力の差は、このグラフ１−２からわかるように、グラフ１−１に対して分布が逆傾向で対応しており、表面屈折力の差は、眼球側表面の主注視線上を通過した光線に対して、物体側表面で発生した非点収差を相殺するように与えられていることがわかる。
この結果、物体側表面と眼球側表面の屈折表面を合わせて処方値に基づいた遠用度数と加入度数とを与えることができるようになっている。
なお、これらのグラフは、面構成の基本的な違いを説明するグラフであり、周辺部の非点収差除去のための非球面化や、乱視度数対応のための乱視成分付加などの場合などの要素は省略してある。（以下、実施例２〜７も同様） In the graph 1-1, as shown in the graph, the graph CV1 (solid line) representing the surface refractive power distribution in the vertical direction along the main gazing line on the object side surface has a refractive power distribution in the progressive zone portion to the near portion. However, the graph CH1 (dotted line) representing the surface refractive power distribution in the lateral direction does not change. Further, the graph CV1 (solid line) representing the surface refractive power distribution in the vertical direction and the graph CH1 (dotted line) representing the surface refractive power distribution in the horizontal direction have different surface refractive powers from the progressive zone to the near portion.
In this case, astigmatism is generated by the amount of the difference in surface refractive power between the vertical direction and the horizontal direction in the light beam that has optically passed on the main line of sight on the object side surface.
On the other hand, in the graph 1-2, as shown in the figure, the graph CV2 (solid line) representing the surface refractive power distribution in the vertical direction along the main gazing line on the eyeball side surface has a refractive power distribution of the distance portion to the progressive portion. There is no change from the belt part to the near part. On the other hand, the graph CH2 (dotted line) representing the surface refractive power distribution in the horizontal direction has different surface refractive powers from the progressive zone to the near portion. Further, the surface refractive power distribution of the graph CV2 (solid line) representing the surface refractive power distribution in the vertical direction and the graph CH2 (dotted line) representing the surface refractive power distribution in the horizontal direction is also a progressive band as in the case of the graph 1-1. It differs from the part to the near part.
However, as can be seen from the graph 1-2, the difference in the surface refractive power corresponds to the graph 1-1 in a reverse trend, and the difference in the surface refractive power is the main gaze on the eyeball side surface. It can be seen that the astigmatism generated on the object side surface is canceled out with respect to the light beam that has passed through the line.
As a result, the dioptric power and the addition power based on the prescription value can be given by combining the refractive surfaces of the object side surface and the eyeball side surface.
In addition, these graphs are graphs for explaining the basic difference in the surface configuration, such as asphericalization for removing astigmatism in the peripheral portion, astigmatism component addition for astigmatism power, etc. Elements are omitted. (The same applies to Examples 2 to 7 below.)

さらに、比較のために、表１−１に掲げた同度数の３種類の従来技術例のレンズの主注視線に沿った表面屈折力分布を表すグラフとして、図１４にグラフＡ−１と２、グラフＢ−１と２、グラフＣ−１と２を併記する。なお、これらのグラフにおける用語の意味は下記の通りである。
Ｆ１：物体側表面の遠用度数測定位置、
Ｆ２：眼球側表面の遠用度数測定位置
Ｎ１：物体側表面の近用度数測定位置、
Ｎ２：眼球側表面の近用度数測定位置
ＣＶ１：物体側表面の主注視線に沿った縦方向の表面屈折力分布を表すグラフ（実線にて表示）
ＣＨ１：物体側表面の主注視線に沿った横方向の表面屈折力分布を表すグラフ（点線にて表示）
ＣＶ２：眼球側表面の主注視線に沿った縦方向の表面屈折力分布を表すグラフ（実線にて表示）
ＣＨ２：眼球側表面の主注視線に沿った横方向の表面屈折力分布を表すグラフ（点線にて表示） Furthermore, for comparison, graphs A-1 and 2 shown in FIG. 14 are graphs showing surface refractive power distributions along the main line of sight of the lenses of the three prior art lenses having the same power listed in Table 1-1. Graphs B-1 and 2 and Graphs C-1 and 2 are shown together. The meanings of terms in these graphs are as follows.
F1: Distance power measurement position on the object side surface,
F2: a distance power measurement position on the eyeball side surface N1: a near power measurement position on the object side surface,
N2: Near-field power measurement position on the eyeball side surface CV1: Graph showing the surface refractive power distribution in the vertical direction along the main line of sight on the object side surface (displayed with a solid line)
CH1: Graph showing the surface refractive power distribution in the lateral direction along the main line of sight on the object side surface (displayed with a dotted line)
CV2: a graph representing the surface refractive power distribution in the vertical direction along the main line of sight on the eyeball side surface (indicated by a solid line)
CH2: Graph showing the surface refractive power distribution in the lateral direction along the main line of sight on the eyeball side surface (displayed with a dotted line)

また、これらのグラフのＦ１，Ｎ１，Ｆ２，Ｎ２における表面屈折力は、前記表１−１に対応しており、ＤＶｆ１〜ＤＨｎ２などの用語の意味もまた、前記表１−１の場合と同一である。なお、これらのグラフの中央にある水平方向の一点鎖線は、物体側表面の平均表面屈折力（Ｆ１とＮ１における縦横の表面屈折力の総平均値）を示している。本発明による実施例１と３種類の従来技術例における物体側表面の平均表面屈折力は、いずれも５．５０ジオプターに統一して比較した。 The surface refractive powers at F1, N1, F2, and N2 in these graphs correspond to those in Table 1-1, and the meanings of terms such as DVf1 to DHn2 are also the same as those in Table 1-1. It is. In addition, the one-dot chain line in the horizontal direction in the center of these graphs indicates the average surface refractive power (total average value of the vertical and horizontal surface refractive powers at F1 and N1) on the object side surface. The average surface refractive power of the object side surface in Example 1 and three types of prior art examples according to the present invention were all compared to 5.50 diopters.

次に、図１５〜図２２に示されるグラフ１−３−で始まる８種類のグラフは、本発明による実施例１のレンズを主注視線に沿って眺めたときの倍率分布を、前述の厳密な倍率計算を行って求めた結果を表すグラフであり、横軸は向って右側がレンズ上方、左側がレンズ下方を、また、縦軸は倍率を表す。図の濃い実線が実施例１であり、薄い鎖線が従来技術例Ａ、濃い鎖線が従来技術例Ｂ、薄い実線が従来技術例Ｃである。以下のこの種のグラフも同じである。なお、横軸は眼球回旋角を用いて視線の方向ごとの比較が出来るようにすると共に、各グラフの縦軸の倍率の縮尺を合わせた。グラフ１−３−の後に付した符号
の意味は、
Ｍｓｖ：縦方向のシェープファクター、
Ｍｓｈ：横方向のシェープファクター
Ｍｐｖ：縦方向のパワーファクター、
Ｍｐｈ：横方向のパワーファクター
Ｍγｖ：縦方向のプリズムファクター、
Ｍγｈ：横方向のプリズムファクター
ＳＭｖ：縦方向の倍率、
ＳＭｈ：横方向の倍率
であり、前述の如く、縦方向の倍率ＳＭｖ及び、横方向の倍率ＳＭｈは、
ＳＭｖ＝Ｍｓｖ×Ｍｐｖ×Ｍγｖ
ＳＭｈ＝Ｍｓｈ×Ｍｐｈ×Ｍγｈ
という関係にある。 Next, eight types of graphs starting with the graph 1-3 shown in FIGS. 15 to 22 show the magnification distribution when the lens of Example 1 according to the present invention is viewed along the main gaze line. FIG. 6 is a graph showing results obtained by performing various magnification calculations, with the horizontal axis facing and the right side above the lens, the left side below the lens, and the vertical axis the magnification. In the figure, the dark solid line is Example 1, the thin chain line is Prior Art Example A, the dark chain line is Prior Art Example B, and the thin solid line is Prior Art Example C. This kind of graph below is the same. In addition, while making it possible to compare for each direction of the line of sight using the eyeball rotation angle on the horizontal axis, the scale of the magnification of the vertical axis of each graph was adjusted. The meaning of the reference signs after the graph 1-3 is
Msv: vertical shape factor,
Msh: shape factor in the horizontal direction Mpv: power factor in the vertical direction,
Mph: Power factor in the horizontal direction Mγv: Prism factor in the vertical direction,
Mγh: prism factor in the horizontal direction SMv: magnification in the vertical direction,
SMh: horizontal magnification, as described above, the vertical magnification SMv and the horizontal magnification SMh are:
SMv = Msv × Mpv × Mγv
SMh = Msh × Mph × Mγh
There is a relationship.

なお、実施例１と前記３種類の従来技術例のレンズはいずれも、屈折率ｎ＝１．６９９、中心厚ｔ＝３．０ｍｍ、幾何学中心ＧＣでプリズムのない仕様、とした。対物パワー（対物距離の逆数）については、Ｆ１，Ｆ２における対物パワーＰｘ＝０．００ジオプター（無限遠方）、Ｎ１，Ｎ２における対物パワーＰｘ＝２．５０ジオプター（４０ｃｍ）とし、他の位置における対物パワーは主注視線に沿った付加屈折力の比率に２．５０ジオプターを乗じて与えた。また、レンズ後頂点から角膜頂点までの距離Ｌ＝１５．０ｍｍ、角膜頂点から眼球回旋中心までの距離ＣＲ＝１３．０ｍｍとした。眼球回旋角θは眼球回旋中心点Ｃを物体側レンズ表面の幾何学中心ＧＣを通る法線上に置き、この法線と視線が一
致したときの回旋角を０度とし、上方を（＋）下方を（−）で表示した。しかる後に、Ｆ１，Ｆ２に対する眼球回旋角θ＝＋１５．０度とし、Ｎ１，Ｎ２に対する眼球回旋角θ＝−３０．０度に統一することにより、累進作用や表面屈折力の分布が表裏いずれの側にあろうとも同一条件で比較できるようになっている。 The lenses of Example 1 and the three types of prior art examples all have a refractive index n = 1.699, a center thickness t = 3.0 mm, a geometric center GC, and no prism. Regarding the objective power (reciprocal of the objective distance), the objective power Px at F1 and F2 is 0.00 diopter (infinitely far), the objective power Px at N1 and N2 is 2.50 diopter (40 cm), and objectives at other positions are used. The power was given by multiplying the ratio of the additional refractive power along the main line of sight by 2.50 diopters. Further, the distance L from the rear vertex of the lens to the apex of the cornea was set to 15.0 mm, and the distance CR from the apex of the cornea to the center of eyeball rotation was set to 13.0 mm. As for the eyeball rotation angle θ, the eyeball rotation center point C is placed on a normal line passing through the geometric center GC of the object side lens surface, the rotation angle when the normal line and the line of sight coincide with each other is 0 degree, and the upper direction is (+) downward Is indicated by (−). After that, by setting the eyeball rotation angle θ = + 15.0 degrees for F1 and F2 and unifying the eyeball rotation angle θ = −30.0 degrees for N1 and N2, the progressive action and the distribution of the surface refractive power are both front and back. It can be compared under the same conditions regardless of the side.

図７の表１−２は本発明による実施例１と、比較のために準備した３種類のレンズの従来技術例について、特定の視線方向に対する厳密な倍率計算結果の一覧表であり、前述の図２１のグラフ１−３−ＳＭｖ（縦方向の総合倍率）と図２２のグラフ１−３−ＳＭｈ（横方向の総合倍率）に対応している。前述の説明の如く、縦方向と横方向では倍率の値が異なるので、双方の倍率を算出してある。ここで表１−２の符号が表す意味は以下のとおりである。
遠用測定点を通過する視線上の縦方向倍率
ＳＭｖｎ：近用測定点を通過する視線上の縦方向倍率
ＳＭｖｆｎ：縦方向倍率差（ＳＭｖｎ−ＳＭｖｆ）
ＳＭｈｆ：遠用測定点を通過する視線上の横方向倍率
ＳＭｈｎ：近用測定点を通過する視線上の横方向倍率
ＳＭｈｆｎ：横方向倍率差（ＳＭｈｎ−ＳＭｈｆ） Table 1-2 in FIG. 7 is a list of strict magnification calculation results for a specific line-of-sight direction for Example 1 according to the present invention and the prior art examples of three types of lenses prepared for comparison. This corresponds to the graph 1-3SMv (total magnification in the vertical direction) in FIG. 21 and the graph 1-3SMh (total magnification in the horizontal direction) in FIG. As described above, since the magnification values are different in the vertical direction and the horizontal direction, both magnifications are calculated. Here, the meanings represented by the symbols in Table 1-2 are as follows.
Longitudinal magnification on the line of sight passing through the distance measurement point SMvn: Vertical magnification on the line of sight passing through the near measurement point SMvfn: Vertical magnification difference (SMvn−SMvf)
SMhf: Horizontal magnification on the line of sight passing through the distance measurement point SMhn: Horizontal magnification on the line of sight passing through the near measurement point SMhfn: Horizontal magnification difference (SMhn-SMhf)

表１−２のＳＭｖｆｎとＳＭｈｆｎ、即ち縦方向倍率差（ＳＭｖｎ−ＳＭｖｆ）と横方向倍率差（ＳＭｈｎ−ＳＭｈｆ）を見てみると、従来技術例Ａが０．１３８０と０．１０１５、Ｂが０．１３６０と０．０９８８、Ｃが０．１３４２と０．０９６１であるのに対し、本発明による実施例１の値は０．１３４２と０．０９５４という低い倍率差に押えられていることがわかる。即ち、本発明による実施例１の遠用部と近用部の倍率差は、従来技術１よりも更に少なくなっているので、像の歪みや揺れについても従来技術１より更に改善されていることがわかる。なお、前述の従来技術１に対応した特許文献２には、倍率
を計算をする上で、縦方向や横方向の違いについて全く考慮されていない。ところが、本発明による実施例１に対応した厳密な倍率計算による図２１のグラフ１−３−ＳＭｖ（縦方向の総合倍率）とグラフ図２２の１−３−ＳＭｈ（横方向の総合倍率）を比べるとすぐにわかるように、縦方向と横方向における像の倍率分布は明白に異なっている。また、この違いは主に近用部とその下方（眼球回旋角で−２０°近辺以下）で顕著なことも容易に読取れる。 Looking at SMvfn and SMhfn in Table 1-2, that is, the longitudinal magnification difference (SMvn-SMvf) and the lateral magnification difference (SMhn-SMhf), the prior art example A is 0.1380, 0.1015, and B is While the values of 0.1360 and 0.0988 and C are 0.1342 and 0.0961, the value of Example 1 according to the present invention is suppressed to a low magnification difference of 0.1342 and 0.0954. Recognize. That is, since the magnification difference between the distance portion and the near portion in the first embodiment according to the present invention is further smaller than that in the prior art 1, the distortion and shaking of the image are further improved as compared with the prior art 1. I understand. Note that Patent Document 2 corresponding to the above-described prior art 1 does not consider the difference between the vertical direction and the horizontal direction at all in calculating the magnification. However, the graph 1-3SMv (total magnification in the vertical direction) in FIG. 21 and the 1-3-3-SMh (total magnification in the horizontal direction) in FIG. 22 by strict magnification calculation corresponding to Example 1 according to the present invention are obtained. As can be readily seen by comparison, the magnification distributions of the images in the vertical and horizontal directions are clearly different. Moreover, it can be easily read that this difference is conspicuous mainly in the near portion and below (the eyeball rotation angle is around −20 ° or less).

前述の倍率の計算式、
縦方向の倍率ＳＭｖ＝Ｍｓｖ×Ｍｐｖ×Ｍγｖ
横方向の倍率ＳＭｈ＝Ｍｓｈ×Ｍｐｈ×Ｍγｈ
にあるように、グラフ１−３−ＳＭｖは、３つの要素、グラフ１−３−Ｍｓｖとグラフ１−３−Ｍｐｖとグラフ１−３−Ｍγｖの値を掛け合わせて得られ、同様に、グラフ１−３−ＳＭｈは、３つの要素、グラフ１−３−Ｍｓｈとグラフ１−３−Ｍｐｈとグラフ１−３−Ｍγｈの値を掛け合わせて得られる。ここで各々の要素の縦方向と横方向を比べると、シェイプファクターであるＭｓｖとＭｓｖには明確な差が見られないが、ＭｐｖとＭｐｈでは近用部より下方（眼球回旋角で−２５°近辺以下）に違いが見られる。また、ＭγｖとＭγｈでは近用部とその下方（眼球回旋角で−１５°近辺以下）に顕著な違いがある。即ち、グラフ１−３−ＳＭｖとグラフ１−３−ＳＭｈの違いの主たる原因は、ＭγｖとＭγｈの違いであり、副次的な原因はＭｐｖとＭｐｈの違いであって、ＭｓｖとＭｓｈには明確な差が見られず、ほとんど無関係であることがわかる。つまり、従来技術１に対応した特許文献２に縦方向や横方向の倍率の違いが見
られないのは、倍率の違いの主たる原因であるプリズムファクターＭγｖとＭγｈを全く考慮しておらず、副次的な原因であるパワーファクターＭｐｖとＭｐｈについても対物距離や視線とレンズとの角度を無視しているので差が出ないのである。更に、従来技術１において改善の根拠とされているシェイプファクターＭｓｖとＭｓｈについても、本発明の実施例１で用いた縮尺で見る限り、遠近の倍率差に各例相互の違いが見られない。 The above formula for calculating magnification,
Vertical magnification SMv = Msv × Mpv × Mγv
Horizontal magnification SMh = Msh × Mph × Mγh
Graph 1-3-3-SMv is obtained by multiplying the values of three elements, Graph 1-3-Msv, Graph 1-3-Mpv, and Graph 1-3-Mγv, and similarly, 1-3SMh is obtained by multiplying the values of three elements, graph 1-3Msh, graph 1-3Mph, and graph 1-3Mγh. Here, when comparing the vertical direction and the horizontal direction of each element, there is no clear difference between the shape factors Msv and Msv, but Mpv and Mph are below the near part (−25 ° in the eyeball rotation angle). There is a difference in the vicinity). Further, in Mγv and Mγh, there is a remarkable difference between the near portion and the lower portion (the eyeball rotation angle is around −15 ° or less). That is, the main cause of the difference between the graph 1-3SMv and the graph 1-3-3-SMh is the difference between Mγv and Mγh, and the secondary cause is the difference between Mpv and Mph. It can be seen that there is no clear difference and it is almost irrelevant. In other words, the reason why no difference in magnification in the vertical direction and the horizontal direction is seen in Patent Document 2 corresponding to the prior art 1 does not consider the prism factors Mγv and Mγh which are the main causes of the difference in magnification. Regarding power factors Mpv and Mph which are the next causes, the objective distance and the angle between the line of sight and the lens are ignored, so there is no difference. Further, regarding the shape factors Msv and Msh, which are grounds for improvement in the prior art 1, as long as the scale factors used in the first embodiment of the present invention are viewed, there is no difference between the examples in the perspective magnification difference.

なお、従来技術１では「遠用部と近用部の倍率差を減らす」ことで「像の歪みや揺れを少なく出来る」としているが、本発明では更に「縦方向と横方向の倍率差を減らす」ことも「像の歪みや揺れを少なく出来る」効果があると考える。即ち、四角い物が扁平に見えたり、丸い物が楕円形に見えたりすることを避けようとするのである。この視覚的な感覚の向上については「差を減らす」ことより「比率を１に近づける」と捉える方が本質的であろう。ここで重要なのは、四角い物が扁平に見えたり、丸い物が楕円形に見えたりする感覚は「遠近比」ではなく「縦横比」であるということである。即ち、本発明では「遠用
部と近用部の倍率差を減らす」ことばかりではなく、更に重要な改善として「縦方向と横方向の倍率差を減らし、倍率比を１に近づける」ことにより「像の歪みや揺れを少なく出来る」という改善効果が得られるのである。なお、これらの傾向は主に近用部より下方（眼球回旋角で−２５°近辺以下）で顕著である。 In the prior art 1, “reducing the magnification difference between the distance portion and the near portion” indicates that “the distortion and shaking of the image can be reduced”. “Reducing” also has the effect of “reducing distortion and shaking of the image”. That is, it tries to avoid that a square object looks flat or a round object looks oval. This improvement in visual sensation may be more essential in terms of “making the ratio closer to 1” than “reducing the difference”. What is important here is that the sense that a square object looks flat or a round object looks oval is not an “perspective ratio” but an “aspect ratio”. That is, in the present invention, not only “reducing the magnification difference between the distance portion and the near portion” but also as an important improvement “by reducing the magnification difference between the vertical direction and the horizontal direction and bringing the magnification ratio closer to 1”. The improvement effect that “the distortion and shaking of the image can be reduced” can be obtained. In addition, these tendencies are conspicuous mainly below the near portion (at an eyeball rotation angle of around −25 ° or less).

ここで、実施例１に係るレンズの非点収差分布、および平均度数分布の測定結果を示す。尚、測定結果は、０．２５ディオプトリピッチの等水準点を結んだ曲線を用いて示した。
また、本願明細書で開示する図面はすべて右眼レンズで、レンズ径は５０mmとして説明する。
図３９は、両面設計レンズの透過状態における非点収差分布を示す図であり、図４０は、同じく平均度数分布を示す図である。
図４１は、両面設計レンズの凸面側（第１面）の非点収差分布を示す図であり、図４２は、同じく平均度数分布を示す図である。特に、非点収差分布と平均度数分布において、累進帯部がほぼ直線状に近い形状なっていることが理解される。完全な直線でないのは、非球面成分が含まれているためである。
図４３は、両面設計レンズの凸面側（第１面）の屈折表面における横（水平）方向の度数分布を示す図であり、図４４は、同じく屈折表面における縦（垂直）方向の度数分布を示す図である。
図４５は、両面設計レンズの凹面側の非点収差分布を示す図であり、図４６は、同じく平均度数分布を示す図である。
図４７は、両面設計レンズの凹面側（第２面）の屈折表面における横（水平）方向の度数分布を示す図であり、図４８は、同じく屈折表面における縦（垂直）方向の度数分布を示す図である。
また、比較のため、従来の技術に係るレンズの非点収差分布、および平均度数分布の測定結果を示す。
図４９は、従来の技術に係るレンズの凸面側（第１面）の非点収差分布を示す図であり、図５０は、同じく平均度数分布を示す図である。
図５１は、従来の技術に係るレンズの凸面側（第１面）の屈折表面における横（水平）方向の度数分布を示す図であり、図５２は、同じく屈折表面における縦（垂直）方向の度数分布を示す図である。
尚、従来の技術に係るレンズの場合、凹面側（第２面）は、球面または乱視面であり、０．２５ディオプトリピッチの等水準点を結んだ曲線を引くことはできないので省略した。 Here, measurement results of astigmatism distribution and average power distribution of the lens according to Example 1 are shown. In addition, the measurement result was shown using the curve which connected the iso-level point of 0.25 diopter pitch.
All drawings disclosed in this specification are right-eye lenses, and the lens diameter is 50 mm.
FIG. 39 is a diagram showing the astigmatism distribution in the transmission state of the double-sided design lens, and FIG. 40 is a diagram showing the average power distribution as well.
FIG. 41 is a diagram showing the astigmatism distribution on the convex surface side (first surface) of the double-sided design lens, and FIG. 42 is a diagram showing the average power distribution as well. In particular, in the astigmatism distribution and the average power distribution, it is understood that the progressive zone has a shape that is almost linear. The reason for not being a perfect straight line is that an aspherical component is included.
FIG. 43 is a diagram showing the frequency distribution in the horizontal (horizontal) direction on the refractive surface on the convex surface side (first surface) of the double-sided design lens, and FIG. 44 shows the frequency distribution in the vertical (vertical) direction on the refractive surface. FIG.
FIG. 45 is a diagram showing the astigmatism distribution on the concave surface side of the double-sided design lens, and FIG. 46 is a diagram showing the average power distribution as well.
FIG. 47 is a diagram showing the frequency distribution in the horizontal (horizontal) direction on the refractive surface on the concave surface (second surface) of the double-sided design lens, and FIG. 48 shows the frequency distribution in the vertical (vertical) direction on the refractive surface. FIG.
For comparison, the measurement results of the astigmatism distribution and the average power distribution of the lens according to the related art are shown.
FIG. 49 is a diagram showing the astigmatism distribution on the convex surface side (first surface) of the lens according to the prior art, and FIG. 50 is a diagram showing the average power distribution as well.
FIG. 51 is a diagram showing the frequency distribution in the horizontal (horizontal) direction on the refractive surface on the convex surface side (first surface) of the lens according to the prior art, and FIG. 52 is also the vertical (vertical) direction on the refractive surface. It is a figure which shows frequency distribution.
In the case of a lens according to the prior art, the concave surface (second surface) is a spherical surface or an astigmatic surface, and is omitted because a curve connecting equal level points of 0.25 diopter pitch cannot be drawn.

（実施例２）
図８の表２−１は本発明による実施例２の表面屈折力に関する一覧表である。この実施例２のレンズの度数はＳ＋６．００Ａｄｄ３．００に対応しており、比較のために同度数の３種類の従来技術例を併記してある。なお、これらの従来技術の記載方法、用語等は実施例１と同様である。（以下の実施例の説明においても同様である。） (Example 2)
Table 2-1 in FIG. 8 is a list relating to the surface refractive power of Example 2 according to the present invention. The lens power of Example 2 corresponds to S + 6.00 Add3.00, and three prior art examples of the same power are shown for comparison. Note that the description methods, terms, and the like of these prior arts are the same as those in the first embodiment. (The same applies to the description of the following embodiments.)

さらに、比較のために表２−１に掲げた同度数の３種類の従来技術例の主注視線に沿った表面屈折力分布を表すグラフとして、前記実施例１において用いたグラフＡ−１とＡ−２、グラフＢ−１とＢ−２、グラフＣ−１とＣ−２を再び用いる。従って、これらのグラフの用語の意味は前記実施例１と同様であるが、Ｆ１，Ｎ１，Ｆ２，Ｎ２における表面屈折力は、表２−１にも対応しているものとし、また中央にある水平方向の一点鎖線が示す物体側表面の平均表面屈折力も表２−１に対応させる都合から、いずれも１０．５０ジオプターという深いカーブとなっている。 Further, as a graph representing the surface refractive power distribution along the main line of sight of the three prior art examples of the same power listed in Table 2-1, for comparison, the graph A-1 used in Example 1 and A-2, graphs B-1 and B-2, and graphs C-1 and C-2 are used again. Therefore, the meanings of the terms in these graphs are the same as those in the first embodiment, but the surface refractive powers in F1, N1, F2, and N2 also correspond to Table 2-1, and are in the center. The average surface refractive power of the object-side surface indicated by the one-dot chain line in the horizontal direction also has a deep curve of 10.50 diopters for the convenience of corresponding to Table 2-1.

図１０のグラフ２−１、グラフ２−２において、物体側表面の主注視線に沿った縦方向の表面屈折力分布を表すグラフＣＶ１（実線）、および横方向の表面屈折力分布を表すグラフＣＨ１（点線）、および眼球側表面の主注視線に沿った縦方向の表面屈折力分布を表すグラフＣＶ２（実線）、および横方向の表面屈折力分布を表すグラフＣＨ２（点線）の遠用部〜累進帯部〜近用部までの変化の態様は、実施例１と同様な傾向を示している。このことから、表面屈折力の差は、眼球側表面の主注視線上を通過した光線に対して、物体側表面で発生した非点収差を相殺するように与えられていることがわかる。
この結果、実施例２においても、実施例１と同様に物体側表面と眼球側表面の屈折表面を合わせて処方値に基づいた遠用度数と加入度数とを与えることができるようになっている。 In graphs 2-1 and 2-2 of FIG. 10, a graph CV1 (solid line) representing the surface refractive power distribution in the vertical direction along the main gaze line on the object side surface, and a graph representing the surface refractive power distribution in the horizontal direction. The distance portion of CH1 (dotted line) and graph CV2 (solid line) representing the surface refractive power distribution in the vertical direction along the main gaze line on the eyeball side surface, and graph CH2 (dotted line) representing the surface refractive power distribution in the horizontal direction The mode of change from the progressive zone to the near portion shows the same tendency as in the first embodiment. From this, it can be seen that the difference in surface refractive power is given so as to cancel the astigmatism generated on the object side surface with respect to the light beam that has passed on the main gaze line on the eyeball side surface.
As a result, also in the second embodiment, as in the first embodiment, the dioptric power and the addition power based on the prescription value can be given by combining the refractive surfaces of the object side surface and the eyeball side surface. .

次に、図２３〜図３０に示した「グラフ２−３−」で始まる８種類のグラフは、本発明による実施例２のレンズを主注視線に沿って眺めたときの倍率分布を、前述の厳密な倍率計算を行って求めた結果を表すグラフである。用語や「グラフ２−３−」の後に付した符号の意味などは、図の濃い実線が実施例２である以外は、前記実施例１の場合と同様である。なお、実施例２と前記３種類の従来技術例で用いた屈折率や対物パワー、眼球回旋角などは、いずれも前記実施例１の場合と同様としたが、実施例２と前記３種類の従来技術例の度数がＳ＋６．００Ａｄｄ３．００であることから、中心厚ｔだけは６．０ｍｍとして実際の製品に近づけた。 Next, eight types of graphs beginning with “Graph 2-3” shown in FIGS. 23 to 30 show the magnification distribution when the lens of Example 2 according to the present invention is viewed along the main line of sight. It is a graph showing the result calculated | required by performing exact | strict magnification calculation of. The terms and the meanings of the symbols attached after “Graph 2-3” are the same as those in Example 1 except that the solid line in the figure is Example 2. The refractive index, objective power, and eyeball rotation angle used in Example 2 and the three types of prior art examples are the same as those in Example 1, but Example 2 and the three types of prior art are the same. Since the frequency of the prior art example is S + 6.00 Add3.00, only the center thickness t is set to 6.0 mm, which is close to an actual product.

図８の表２−２は、本発明による実施例２と、比較のために準備した３種類の従来技術例について、特定の視線方向に対する厳密な倍率計算結果の一覧表であり、前述のグラフ２−３−ＳＭｖ（縦方向の総合倍率）とグラフ２−３−ＳＭｈ（横方向の総合倍率）に対応している。ここで、表２−２の符号が表す意味は前述の表１−２の意味と同様である。 Table 2-2 in FIG. 8 is a list of strict magnification calculation results for a specific line-of-sight direction for Example 2 according to the present invention and three types of conventional technology prepared for comparison. It corresponds to 2-3-3-SMv (total magnification in the vertical direction) and graph 2-3-SMh (total magnification in the horizontal direction). Here, the meanings represented by the symbols in Table 2-2 are the same as those in Table 1-2.

表２−２のＳＭｖｆｎとＳＭｈｆｎ、即ち縦方向倍率差（ＳＭｖｎ−ＳＭｖｆ）と横方向倍率差（ＳＭｈｎ−ＳＭｈｆ）を見てみると、従来技術例Ａが０．２２７５と０．１３２５、Ｂが０．２２７７と０．１２６８、Ｃが０．２２８０と０．１２１０であるのに対し、本発明による実施例２の値は、０．２１５１と０．１１９９という低い倍率差に押えられていることがわかる。即ち、本発明による実施例２の遠用部と近用部の倍率差は、従来技術１よりも更に少なくなっているので、像の歪みや揺れについても従来技術１より更に改善されていることがわかる。なお、前述の実施例１と同様に、本発明による実施例２に対応した厳密な倍率計算によるグラフ２−３−ＳＭｖ（縦方向の総合倍率）とグラフ２−３−ＳＭｈ（横方向の総合倍率）を比べるとすぐにわかるように、縦方向と横方向における像の倍率分布は明白に異なっている。 When SMvfn and SMhfn in Table 2-2, that is, the longitudinal magnification difference (SMvn-SMvf) and the lateral magnification difference (SMhn-SMhf) are examined, the prior art example A is 0.2275, 0.1325, and B is While the values of 0.2277 and 0.1268 and C are 0.2280 and 0.1210, the value of Example 2 according to the present invention is suppressed to a low magnification difference of 0.2151 and 0.1199. I understand. That is, the magnification difference between the distance portion and the near portion according to the second embodiment of the present invention is further smaller than that of the prior art 1, and therefore image distortion and shaking are further improved compared to the prior art 1. I understand. Similar to the above-described first embodiment, a graph 2-3SMv (total magnification in the vertical direction) and a graph 2-3-3-SMh (total in the horizontal direction) by strict magnification calculation corresponding to the second embodiment according to the present invention. As can be readily seen by comparing (magnification), the magnification distribution of the image in the vertical and horizontal directions is clearly different.

また、この違いは、主に中間部から下方（眼球回旋角で−１０°近辺以下）で顕著なことも容易に読取れる。さて、前述の実施例１と同様に、実施例２においてもグラフ２−３−ＳＭｖは３つの要素、グラフ２−３−Ｍｓｖとグラフ２−３−Ｍｐｖとグラフ２−３−Ｍγｖの値を掛け合わせて得られ、同様に、グラフ２−３−ＳＭｈは３つの要素、グラフ２−３−Ｍｓｈとグラフ２−３−Ｍｐｈとグラフ２−３−Ｍγｈの値を掛け合わせて得られる。ここで各々の要素の縦方向と横方向を比べると、シェイプファクターであるＭｓｖとＭｓｖには明確な差が見られないが、ＭｐｖとＭｐｈでは近用部より下方（眼球回旋角
で−２０°近辺以下）に違いが見られる。また、ＭγｖとＭγｈでは中間部から下方（眼球回旋角で−１０°近辺以下）に顕著な違いがある。ここで遠用部の上方（眼球回旋角で＋２０°近辺以上）にも差が見られるが、各例による差が出るのは遠用部のかなり上方（眼球回旋角で＋３０°近辺以上）であり、使用頻度も少ないので無視しうる。 In addition, it can be easily read that this difference is conspicuous mainly downward from the middle part (in the vicinity of −10 ° or less in eyeball rotation angle). As in the first embodiment, in the second embodiment, the graph 2-3-SMv has three elements, the values of the graph 2-3-3-Msv, the graph 2-3-3-Mpv, and the graph 2-3-3-Mγv. Similarly, graph 2-3-3-SMh is obtained by multiplying the values of three elements, graph 2-3-3-Msh, graph 2-3-3-Mph, and graph 2-3-3-Mγh. Here, when the vertical and horizontal directions of each element are compared, there is no clear difference between the shape factors Msv and Msv. There is a difference in the vicinity). Further, there is a significant difference between Mγv and Mγh from the middle portion downward (eye rotation angle is around −10 ° or less). Here, a difference is also seen above the distance portion (in the vicinity of + 20 ° or more in the eyeball rotation angle), but the difference in each example is significantly above the distance portion (in the vicinity of + 30 ° or more in the eyeball rotation angle). Yes, it can be ignored because it is not used frequently.

即ち、前述の実施例１と同様に、実施例２においても図２９のグラフ２−３−ＳＭｖと図３０のグラフ２−３−ＳＭｈの違いの主たる原因は、ＭγｖとＭγｈの違いであり、副次的な原因はＭｐｖとＭｐｈの違いであって、ＭｓｖとＭｓｈには明確な差が見られず、ほとんど無関係であることがわかる。更に、従来技術１において改善の根拠とされているシェイプファクターＭｓｖとＭｓｈについても、本発明の実施例２で用いた縮尺で見る限り、遠近の倍率差に各例相互の違いが見られない。なお、実施例２においても、前述の実施例１と同様に、「遠用部と近用部の倍率差を減らす」ことばかりではなく、更に重要な
改善として「縦方向と横方向の倍率差を減らし、倍率比を１に近づける」ことにより「像の歪みや揺れを少なく出来る」という改善効果が得られている。なお、これらの傾向は主に近用部より下方（眼球回旋角で−２５°近辺以下）で顕著である。 That is, in the same manner as in Example 1 described above, also in Example 2, the main cause of the difference between the graph 2-3SMv in FIG. 29 and the graph 2-3-3-SMh in FIG. 30 is the difference between Mγv and Mγh. A secondary cause is the difference between Mpv and Mph, and there is no clear difference between Msv and Msh, indicating that they are almost irrelevant. Further, regarding the shape factors Msv and Msh, which are grounds for improvement in the prior art 1, as long as the scale factors used in the second embodiment of the present invention are used, there is no difference between the examples in the perspective difference. In the second embodiment, as in the first embodiment described above, not only “reducing the magnification difference between the distance portion and the near portion” but also as an important improvement “the magnification difference between the vertical direction and the horizontal direction”. By reducing the magnification ratio and bringing the magnification ratio closer to 1, an improvement effect of “reducing image distortion and shaking” is obtained. In addition, these tendencies are conspicuous mainly below the near portion (at an eyeball rotation angle of around −25 ° or less).

（実施例３）
図９の表３−１は本発明による実施例３の表面屈折力に関する一覧表である。
この実施例３の度数はＳ−６．００Ａｄｄ３．００に対応しており、比較のために同度数の３種類の従来技術例を併記してある。 (Example 3)
Table 3-1 in FIG. 9 is a list relating to the surface refractive power of Example 3 according to the present invention.
The frequency of Example 3 corresponds to S-6.00 Add3.00, and three types of prior art examples of the same frequency are also shown for comparison.

図１１のグラフ３−１と２は本発明による実施例３の主注視線に沿った表面屈折力分布を表すグラフである。ここで、グラフ３−１は物体側表面に対応し、グラフ３−２は眼球側表面に対応している。 Graphs 3-1 and 2 in FIG. 11 are graphs showing the surface refractive power distribution along the main line of sight of Example 3 according to the present invention. Here, the graph 3-1 corresponds to the object side surface, and the graph 3-2 corresponds to the eyeball side surface.

さらに、比較のために図９の表３−１に掲げた同度数の３種類の従来技術例の主注視線に沿った表面屈折力分布を表すグラフとして、前記実施例１や２において用いたグラフＡ−１と２、グラフＢ−１と２、グラフＣ−１と２を再び用いる。Ｆ１，Ｎ１，Ｆ２，Ｎ２における表面屈折力は、表３−１にも対応しているものとし、また中央にある水平方向の一点鎖線が示す物体側表面の平均表面屈折力も表３−１に対応させる都合から、いずれも２．５０ジオプターという浅いカーブとなっているものとする。 Furthermore, as a graph showing the surface refractive power distribution along the main line of sight of the three prior art examples of the same power listed in Table 3-1 of FIG. 9 for comparison, the graph was used in Examples 1 and 2 described above. Graphs A-1 and 2, Graphs B-1 and 2, and Graphs C-1 and 2 are used again. The surface refractive powers at F1, N1, F2, and N2 also correspond to those in Table 3-1, and the average surface refractive power of the object-side surface indicated by the one-dot chain line in the horizontal direction at the center is also shown in Table 3-1. For convenience, it is assumed that each has a shallow curve of 2.50 diopters.

図１２のグラフ３−１、グラフ３−２において、物体側表面の主注視線に沿った縦方向の表面屈折力分布を表すグラフＣＶ１（実線）、および横方向の表面屈折力分布を表すグラフＣＨ１（点線）、および眼球側表面の主注視線に沿った縦方向の表面屈折力分布を表すグラフＣＶ２（実線）、および横方向の表面屈折力分布を表すグラフＣＨ２（点線）の遠用部〜累進帯部〜近用部までの変化の態様は、実施例１、実施例２と同様な傾向を示しており、表面屈折力の差は、眼球側表面の主注視線上を通過した光線に対して、物体側表面で発生した非点収差を相殺するように与えられていることがわかる。この結果、実施例
１、実施例２と同様に物体側表面と眼球側表面の屈折表面を合わせて処方値に基づいた遠用度数と加入度数とを与えることができるようになっている。 In graphs 3-1 and 3-2 in FIG. 12, a graph CV1 (solid line) representing the surface refractive power distribution in the vertical direction along the main gaze line on the object side surface, and a graph representing the surface refractive power distribution in the horizontal direction. The distance portion of CH1 (dotted line) and graph CV2 (solid line) representing the vertical surface refractive power distribution along the main gaze line on the eyeball side surface, and graph CH2 (dotted line) representing the surface refractive power distribution in the horizontal direction The mode of change from the progressive zone to the near portion shows the same tendency as in Example 1 and Example 2, and the difference in surface refractive power is caused by the light rays that have passed on the main gaze on the eyeball side surface. On the other hand, it can be seen that the astigmatism generated on the object side surface is given to cancel. As a result, the distance power and the addition power based on the prescription value can be given by combining the refractive surfaces of the object side surface and the eyeball side surface in the same manner as in the first and second embodiments.

次に、図３１〜図３８に示したグラフ３−３−で始まる８種類のグラフは、実施例３のレンズを主注視線に沿って眺めたときの倍率分布を、前述の厳密な倍率計算を行って求めた結果を表すグラフである。なお、実施例３と前記３種類の従来技術例で用いた屈折率や対物パワー、眼球回旋角などは、いずれも前記実施例１や２の場合と同様としたが、実施例３と前記３種類の従来技術例の度数がＳ−６．００Ａｄｄ３．００であることから、中心厚ｔだけは１．０ｍｍとして実際の製品に近づけた。 Next, eight types of graphs starting with the graph 3-3 shown in FIGS. 31 to 38 show the magnification distribution when the lens of Example 3 is viewed along the main gazing line, and the above-described strict magnification calculation. It is a graph showing the result calculated | required by performing. The refractive index, objective power, eyeball rotation angle, etc. used in Example 3 and the three types of prior art examples are the same as those in Examples 1 and 2, but Examples 3 and 3 Since the frequency of the type of prior art example is S-6.00 Add3.00, only the center thickness t was set to 1.0 mm, which was close to an actual product.

図９の表３−２は本発明による実施例３と、比較のために準備した３種類の従来技術例について、特定の視線方向に対する厳密な倍率計算結果の一覧表であり、前述のグラフ３−３−ＳＭｖ（縦方向の総合倍率）とグラフ３−３−ＳＭｈ（横方向の総合倍率）に対応している。 Table 3-2 in FIG. 9 is a list of strict magnification calculation results for a specific line-of-sight direction for Example 3 according to the present invention and three types of prior art examples prepared for comparison. It corresponds to -3-SMv (total magnification in the vertical direction) and graph 3-3SMh (total magnification in the horizontal direction).

表３−２のＳＭｖｆｎとＳＭｈｆｎ、即ち、縦方向倍率差（ＳＭｖｎ−ＳＭｖｆ）と横方向倍率差（ＳＭｈｎ−ＳＭｈｆ）とを見てみると、従来技術例Ａが０．０４７５と０．０７７４、Ｂが０．０４１８と０．０７５０、Ｃが０．０３６３と０．０７２７であるのに対し、本発明による実施例２の値は０．０５１２と０．０７２６という値であり、縦方向倍率差は増えているが横方向倍率差は減っていることがわかる。ただし、縦方向倍率差は前述の実施例１や実施例２に比べていずれも１／３乃至１／５といった低い値であり、横方向倍率差がわずかながら減っていることを考え合わせると、実施例３の遠用部と近用部の倍率差は、従来技術１に比べて大差ないと言える。ところが、実施例３に対応した厳密な倍率計算によるグラフ３−３−ＳＭｖ（縦方向の総合倍率）とグラフ３−３−ＳＭｈ（横方向の総合倍率）を観察すると、実施例３は従来例に比べ、特に近用部より下方（眼球回旋角で−２０°近辺以下）における「縦方向の倍率が１より小さくなる傾向」が最も少なく、結果的に「縦横の倍率差」が最も少なくなっており、像の歪みや揺れが従来例よりも改善されている。 Looking at SMvfn and SMhfn in Table 3-2, that is, the longitudinal magnification difference (SMvn−SMvf) and the lateral magnification difference (SMhn−SMhf), the prior art example A is 0.0475 and 0.0774, Whereas B is 0.0418 and 0.0750, and C is 0.0363 and 0.0727, the values of Example 2 according to the present invention are values of 0.0512 and 0.0726. It can be seen that the horizontal magnification difference is decreasing, though increasing. However, considering that the vertical magnification difference is a low value such as 1/3 to 1/5 of both the above-described Example 1 and Example 2 and the lateral magnification difference is slightly reduced, It can be said that the magnification difference between the distance portion and the near portion in Example 3 is not much different from that in the related art 1. However, when observing the graph 3-3-SMv (total magnification in the vertical direction) and the graph 3-3-SMh (total magnification in the horizontal direction) by strict magnification calculation corresponding to Example 3, Example 3 is the conventional example. In particular, the “vertical magnification tends to be smaller than 1” is less in the lower part than the near-use portion (the eye rotation angle is around −20 ° or less), and as a result, the “vertical / horizontal magnification difference” is the smallest. The distortion and shaking of the image is improved compared to the conventional example.

なお、図３７のグラフ３−３−ＳＭｖ（縦方向の総合倍率）において、縦方向と横方向における像の倍率分布に顕著な違いが出るのは中間部から下方（眼球回旋角で−１０°近辺以下）と遠用部の上方（眼球回旋角で＋１０°近辺以上）であるが、各例による差が出るのは近用部より下方（眼球回旋角で−２０°近辺以下）と遠用部のやや上方（眼球回旋角で＋２５°近辺以上）である。この内、遠用部のやや上方については使用頻度も少ないので無視しうるが、近用部より下方については使用頻度も多く、無視し得ない。その結果、本発明による実施例３は従来例に比べ、特に近用部より下方（眼球回旋角で−２０°近
辺以下）において縦方向の倍率が１に最も近く、その結果「縦横の倍率差」が最も少なくなっており、従来例よりも像の歪みや揺れが改善されているのである。なお、これらの傾向は主に近用部より下方（眼球回旋角で−２５°近辺以下）で顕著である。また、従来技術１において改善の根拠とされているシェイプファクターＭｓｖとＭｓｈについては、本発明の実施例１や実施例２と同様に、実施例３で用いた縮尺で見ても、遠近の倍率差に各例相互の違いが見られない。 Note that in the graph 3-3-SMv (total magnification in the vertical direction) in FIG. 37, the difference in image magnification distribution between the vertical direction and the horizontal direction is lower than the middle part (−10 ° in the eyeball rotation angle). Nearer and below) and above the distance part (eye rotation angle around + 10 ° or more), but the difference in each case is below the near part (eye rotation angle around -20 ° or less) and distance use It is slightly above the part (eye rotation angle around + 25 ° or more). Of these, the frequency of use slightly above the distance portion is small and can be ignored, but the frequency below the near portion is high and cannot be ignored. As a result, in Example 3 according to the present invention, compared with the conventional example, the vertical magnification is closest to 1 below the near portion (the eye rotation angle is about -20 ° or less). "Is the least, and image distortion and shaking are improved compared to the conventional example. In addition, these tendencies are conspicuous mainly below the near portion (at an eyeball rotation angle of around −25 ° or less). Further, the shape factors Msv and Msh, which are grounds for improvement in the prior art 1, are similar to the first and second embodiments of the present invention, even when viewed at the scale used in the third embodiment. There is no difference between the examples.

（実施例４〜７）
本発明の実施例として、前述の実施例１〜３の他にも特許請求の範囲に記載した範囲内で、様々な表面屈折力の分布の組合わせが可能である。ここで、実施例１と同度数の応用例として実施例４〜６を、また実施例２と同度数の応用例として実施例７を示す。これらの実施例の表面屈折力と特定の視線方向に対する厳密な倍率計算結果の一覧表とグラフを図７の表１−１、表１−２及び図１２〜図１４のグラフ４−１、グラフ４−２乃至グラフ７−１、グラフ７−２に示す。 (Examples 4 to 7)
As an embodiment of the present invention, in addition to the first to third embodiments described above, various surface refractive power distribution combinations are possible within the scope described in the claims. Here, Examples 4 to 6 are shown as application examples of the same degree as Example 1, and Example 7 is shown as an application example of the same degree as Example 2. A list and graphs of strict magnification calculation results for the surface refractive power and specific line-of-sight direction of these examples are shown in Table 1-1, Table 1-2 in FIG. 7, and Graph 4-1 in FIGS. It is shown in 4-2 to graph 7-1 and graph 7-2.

（変形例）
更に本発明においては通常の処方値のみならず、これまでレンズメーカーが把握することの少なかった眼鏡装用者の個人的ファクターとして、例えば角膜頂点からレンズ後方頂点までの距離、眼球回旋中心からレンズ後方頂点までの距離、左右眼の不等像視の程度、左右眼の高さの差、最も頻度の高い近方視の対物距離、フレームの前傾角（上下方向）、あおり角（左右方向）、レンズのコバ厚方向に対するヤゲン位置、などを入力情報としてレンズ設計に組み入れることにより、カスタムメイド（個別設計）の要求に応えることも可能である。 (Modification)
Further, in the present invention, not only the normal prescription value but also the personal factor of the spectacle wearer, which has been rarely grasped by the lens manufacturer so far, for example, the distance from the apex of the cornea to the apex of the back of the lens, the center of the eyeball rotation and the back of the lens Distance to the apex, degree of unequal image vision of the left and right eyes, difference in height between the left and right eyes, most frequent near vision objective distance, forward tilt angle (vertical direction), tilt angle (horizontal direction), By incorporating the bevel position in the edge thickness direction of the lens into the lens design as input information, it is possible to meet custom-made (individual design) requirements.

（変形例１）
変形例１に係る２種類の両面非球面型累進屈折力レンズについて説明する。 (Modification 1)
Two types of double-sided aspherical progressive-power lenses according to Modification 1 will be described.

変形例１に係る第１の両面非球面型累進屈折力レンズは、
物体側表面である第１の屈折表面と、眼球側表面である第２の屈折表面とに分割配分されている累進屈折力作用を備えた両面非球面型累進屈折力レンズであって、
前記第１の屈折表面において、遠用度数測定位置Ｆ１における横方向の表面屈折力及び縦方向の表面屈折力をそれぞれ、ＤＨｆ、ＤＶｆとし、
前記第１の屈折表面において、近用度数測定位置Ｎ１における横方向の表面屈折力及び縦方向の表面屈折力をそれぞれＤＨｎ、ＤＶｎとするとき、
ＤＶｎ−ＤＶｆ＞ＡＤＤ／２となる関係式を満足させると共に、前記第１の屈折表面のＦ１及びＮ１における表面非点収差成分を、前記第２の屈折表面にて相殺し、前記第１と第２の屈折表面とを合わせて処方値に基づいた加入度数（ＡＤＤ）を与えるようにし、
かつ、
Ｆ１を通る縦方向断面曲線において、Ｆ１からＮ１と同じ高さに至る縦方向断面度数変化の５０％を与える位置を中心として縦方向へ±４ｍｍに位置する２本の水平線と、Ｆ１を通る縦方向の直線から水平方向へ±１５ｍｍに位置する２本の縦線で囲まれた矩形内の任意の位置において、
前記第１の屈折表面における表面縦方向断面度数の微分値は、横方向微分値の絶対値よりも縦方向微分値の絶対値の方が大きいことを特徴とする両面非球面型累進屈折力レンズである。 The first double-sided aspherical progressive-power lens according to Modification 1 is
A double-sided aspherical progressive-power lens having a progressive-power action divided and distributed into a first refractive surface that is an object-side surface and a second refractive surface that is an eyeball-side surface,
In the first refractive surface, the horizontal surface power and the vertical surface power at the distance power measurement position F1 are DHf and DVf, respectively.
In the first refracting surface, when the horizontal surface power and the vertical surface power at the near power measurement position N1 are DHn and DVn, respectively,
DVn−DVf> ADD / 2 is satisfied, and surface astigmatism components at F1 and N1 of the first refracting surface are canceled by the second refracting surface. With the refractive surface of 2 to give an add power (ADD) based on the prescription value,
And,
In the longitudinal section curve passing through F1, two horizontal lines located ± 4 mm in the longitudinal direction centering on the position giving 50% of the longitudinal section frequency change from F1 to the same height as N1, and the longitudinal line passing through F1 At an arbitrary position within a rectangle surrounded by two vertical lines located ± 15 mm horizontally from the direction straight line,
A double-sided aspherical progressive-power lens characterized in that the absolute value of the longitudinal differential value of the differential value of the surface longitudinal cross-sectional power at the first refractive surface is larger than the absolute value of the lateral differential value It is.

変形例１に係る第２の両面非球面型累進屈折力レンズは、
物体側表面である第１の屈折表面と、眼球側表面である第２の屈折表面とに分割配分されている累進屈折力作用を備えた両面非球面型累進屈折力レンズであって、
前記第１の屈折表面において、遠用度数測定位置Ｆ１における横方向の表面屈折力及び縦方向の表面屈折力をそれぞれ、ＤＨｆ、ＤＶｆとし、
前記第１の屈折表面において、近用度数測定位置Ｎ１における横方向の表面屈折力及び縦方向の表面屈折力をそれぞれＤＨｎ、ＤＶｎとするとき、
ＤＶｎ−ＤＶｆ＞ＡＤＤ／２となる関係式を満足させると共に、前記第１の屈折表面のＦ１及びＮ１における表面非点収差成分を、前記第２の屈折表面にて相殺し、前記第１と第２の屈折表面とを合わせて処方値に基づいた加入度数（ＡＤＤ）を与えるようにし、
かつ、
Ｆ１を通る縦方向断面曲線において、Ｆ１からＮ１と同じ高さに至る縦方向断面度数変化の５０％を与える位置を中心として縦方向へ±４ｍｍに位置する２本の水平線と、Ｆ１を通る縦方向の直線から水平方向へ±１５ｍｍに位置する２本の縦線で囲まれた矩形内の任意の位置において、前記第１の屈折表面における表面非点収差量の微分値は、横方向微分値の絶対値よりも縦方向微分値の絶対値の方が大きく、
かつ、
前記矩形内の任意の位置において、
前記第１の屈折表面における表面平均度数の微分値は、横方向微分値の絶対値よりも縦方向微分値の絶対値の方が大きいことを特徴とする両面非球面型累進屈折力レンズである。 The second double-sided aspherical progressive-power lens according to Modification 1 is
A double-sided aspherical progressive-power lens having a progressive-power action divided and distributed into a first refractive surface that is an object-side surface and a second refractive surface that is an eyeball-side surface,
In the first refractive surface, the horizontal surface power and the vertical surface power at the distance power measurement position F1 are DHf and DVf, respectively.
In the first refracting surface, when the horizontal surface power and the vertical surface power at the near power measurement position N1 are DHn and DVn, respectively,
DVn−DVf> ADD / 2 is satisfied, and surface astigmatism components at F1 and N1 of the first refracting surface are canceled by the second refracting surface. With the refractive surface of 2 to give an add power (ADD) based on the prescription value,
And,
In the longitudinal section curve passing through F1, two horizontal lines located ± 4 mm in the longitudinal direction centering on the position giving 50% of the longitudinal section frequency change from F1 to the same height as N1, and the longitudinal line passing through F1 The differential value of the amount of surface astigmatism on the first refractive surface is a lateral differential value at an arbitrary position within a rectangle surrounded by two vertical lines located ± 15 mm in the horizontal direction from the straight line in the direction. The absolute value of the longitudinal differential value is larger than the absolute value of
And,
At any position within the rectangle,
In the double-sided aspherical progressive-power lens, the differential value of the surface average power on the first refractive surface is greater in the absolute value of the longitudinal differential value than in the horizontal direction. .

これらのレンズを設計するにあたり、まず、物体側表面においてＦ１を通る縦方向断面曲線を決定する。この断面曲線は、従来の累進屈折力レンズにおける主子午線の縦方向度数分布を決定する際に持いられる技術で決定することができる。（例えば、本願発明者らによる日本特許第2549738号の設計技術参照）
次に、この曲線を母線とする回転面を定義する。回転面における回転軸は、母線を含む平面内（断面内）において、レンズの幾何学中心における母線の法線に対して垂直な直線であり、
かつ、
Ｆ１における縦方向曲率半径をＲ１、Ｆ１における母線の法線と、幾何学中心における母線の法線とのなす角をΘとしたとき、Ｒ＝Ｒ１＊ＣＯＳΘで定義される距離Ｒだけ、Ｆ１から眼球側へ離れたところに位置する。この回転軸を用いて、先に定義した母線を回転させることで、Ｆ１における縦方向度数と横方向度数とを一致させた物体側表面を定義できる。 In designing these lenses, first, a longitudinal sectional curve passing through F1 on the object side surface is determined. This cross-sectional curve can be determined by a technique possessed when determining the longitudinal power distribution of the main meridian in a conventional progressive-power lens. (For example, see the design technique of Japanese Patent No. 2549738 by the inventors of the present application)
Next, a rotation surface having this curve as a generating line is defined. The rotation axis in the rotation plane is a straight line perpendicular to the normal of the generatrix at the geometric center of the lens in the plane including the generatrix (in the cross section),
And,
When the radius of curvature in the longitudinal direction at F1 is R1, and the angle between the normal of the generatrix at F1 and the normal of the generatrix at the geometric center is Θ, the distance R defined by R = R1 * COSΘ is the distance from F1. Located away from the eyeball. By rotating the generatrix previously defined using this rotation axis, it is possible to define the object-side surface in which the longitudinal power and the lateral power in F1 are matched.

上述の説明において、レンズの物体側表面を回転面としたが、同様の母線を使用したスイープ面でも本発明を実施することが可能である。スイープ面とは、母線を３次元的な曲線（以下、掃引線と呼ぶ）に沿って掃引した面のことである。
図57に一般的なスイープ面の例を示す。
図57においてＦ１を通る縦方向の実線が子午線である。
図58は図57の子午線をレンズ側方から眺めた図であり、Ｏ１はＦ１における子午線の曲率中心点を示し、Ｏ１からＦ１への矢印の長さはＦ１における子午線の曲率半径を示している。上方から下方にかけて矢印の長さが短くなっているのは、子午線に沿っての曲率半径が累進的に変化していることを表している。
図57においてＦ１を通る横方向の破線が掃引線である。
図59は図57の掃引線をレンズ上方から眺めた図であり、Ｏ１はＦ１における掃引線の曲率中心点を示し、Ｏ１からＦ１への矢印の長さはＦ１における掃引線の曲率半径を示している。
３本の矢印の長さが等しいのは、この掃引線がＯ１を中心とした円であることを示している。
図60から図62はさまざまな掃引線の例を示している。
図60はＦ１から離れるにつれて曲率半径が小さくなる掃引線の例を示し、
図61はＦ１から離れるにつれて曲率半径が大きくなる掃引線の例を示し、
図62はＦ１から離れる方向によって曲率半径の変化が異なる掃引線の例を示している。 In the above description, the object-side surface of the lens is a rotating surface, but the present invention can also be implemented on a sweep surface using a similar bus. The sweep surface is a surface obtained by sweeping a bus line along a three-dimensional curve (hereinafter referred to as a sweep line).
FIG. 57 shows an example of a general sweep surface.
In FIG. 57, the vertical solid line passing through F1 is the meridian.
58 is a view of the meridian of FIG. 57 as viewed from the side of the lens. O1 indicates the center of curvature of the meridian at F1, and the length of the arrow from O1 to F1 indicates the radius of curvature of the meridian at F1. . The fact that the length of the arrow decreases from the top to the bottom indicates that the radius of curvature along the meridian changes progressively.
In FIG. 57, a horizontal broken line passing through F1 is a sweep line.
FIG. 59 is a view of the sweep line of FIG. 57 as viewed from above the lens. O1 indicates the center of curvature of the sweep line at F1, and the length of the arrow from O1 to F1 indicates the radius of curvature of the sweep line at F1. ing.
The three arrows having the same length indicate that the sweep line is a circle centered on O1.
60 to 62 show examples of various sweep lines.
FIG. 60 shows an example of a sweep line in which the radius of curvature decreases with distance from F1,
FIG. 61 shows an example of a sweep line in which the radius of curvature increases with distance from F1,
FIG. 62 shows an example of a sweep line in which the change in the radius of curvature differs depending on the direction away from F1.

本変形例１に用いる回転面を含めたスイープ面は、一般的なスイープ面の中でも、特に以下のような特徴を有するものであるが、図面５３〜図５５を参照しながら説明する。
ここで、図５３は、変形例１に係るレンズの物体側表面における縦（垂直）方向の度数分布（第１面）を示す図であり、図５４は、変形例１に係るレンズの物体側表面における表面非点収差分布を示す図でり、図５５は、変形例１に係るレンズの物体側表面における表面平均度数分布を示す図である。そして、各々の図において、Ｆ１を通る縦方向断面曲線の、Ｆ１からＮ１と同じ高さに至る縦方向断面度数変化の５０％を与える位置を中心として縦方向へ±４ｍｍに位置する２本の水平線と、Ｆ１を通る縦方向の直線から水平方向へ±１５ｍｍに位置する２本の縦線とで囲まれた矩形を、破線を用いて示している。
図56は、Ｆ１を通る縦方向断面曲線の度数変化を示すグラフである。縦方向が距離、横方向は、Ｆ１から近用度数測定点Ｎ１と同じ高さに至るまでの度数変化を１００％としたときの、Ｆ１における度数に対する度数変化量のパーセントを表している。この矩形の上下方向の中心位置は、図56に示すように、５０％にあたる位置を矩形の中心としている。
この矩形領域は、累進屈折力レンズにおいて累進作用の特徴をもっとも顕著に表している領域である。 The sweep surface including the rotating surface used in Modification 1 has the following characteristics among general sweep surfaces, and will be described with reference to FIGS. 53 to 55.
53 is a diagram showing a frequency distribution (first surface) in the longitudinal (vertical) direction on the object-side surface of the lens according to Modification Example 1. FIG. 54 is an object side of the lens according to Modification Example 1. FIG. 55 is a diagram showing a surface astigmatism distribution on the surface, and FIG. 55 is a diagram showing a surface average power distribution on the object side surface of the lens according to Modification Example 1. FIG. In each figure, two longitudinal section curves passing through F1 are located at ± 4 mm in the longitudinal direction centering on a position that gives 50% of the longitudinal section frequency change from F1 to the same height as N1. A rectangle surrounded by a horizontal line and two vertical lines positioned ± 15 mm in the horizontal direction from the vertical straight line passing through F1 is shown using a broken line.
FIG. 56 is a graph showing the change in the frequency of the longitudinal section curve passing through F1. The vertical direction represents the distance, and the horizontal direction represents the percentage of the frequency change amount with respect to the frequency at F1 when the frequency change from F1 to the same height as the near-use frequency measurement point N1 is 100%. As shown in FIG. 56, the center position of the rectangle in the vertical direction has a position corresponding to 50% as the center of the rectangle.
This rectangular region is the region that most prominently represents the feature of the progressive action in the progressive-power lens.

図面から明らかなように、本発明に用いる回転面を含めたスイープ面では、縦方向度数は、横方向への移動に対して変化しない。したがって、図５３に示す縦方向断面度数分布の等高線を見ると、上記矩形内では水平線状になる。さらに、回転面においては、図５４に示す表面非点収差分布の等高線や、図５５に示す表面平均度数分布の等高線も縦方向断面度数分布の等高線と同様に上記矩形内で水平線状となる。 As is apparent from the drawings, the longitudinal power does not change with respect to the movement in the lateral direction on the sweep surface including the rotating surface used in the present invention. Therefore, when the contour lines of the longitudinal cross-sectional frequency distribution shown in FIG. 53 are viewed, the contour lines are horizontal lines. Further, on the rotating surface, the contour lines of the surface astigmatism distribution shown in FIG. 54 and the contour lines of the surface average power distribution shown in FIG. 55 are also horizontal lines in the rectangle, similar to the contour lines of the longitudinal section power distribution.

本変形例１に係るレンズには、厳密なスイープ面だけでなく、これに若干の非球面補正が加わるものも含まれる。よって、各分布は完全に水平とはならないが、スイープ面を基にした面においては、上記矩形内のどの位置においても縦方向断面度数の微分値は、横方向微分値の絶対値よりも縦方向微分値の絶対値の方が大きいという特徴をもつ。また、回転面を基にした面においては、上記矩形内のどの位置にいても表面非点収差量の微分値や表面平均度数の微分値は、横方向微分値の絶対値よりも縦方向微分値の絶対値の方が大きいという特徴をもつ。 The lens according to the first modification includes not only a strict sweep surface but also a lens to which a slight aspherical correction is added. Therefore, each distribution is not completely horizontal, but on the surface based on the sweep surface, the differential value of the longitudinal cross-sectional frequency is higher than the absolute value of the horizontal differential value at any position in the rectangle. It has the characteristic that the absolute value of the directional differential value is larger. On the surface based on the rotation surface, the differential value of the surface astigmatism amount and the differential value of the surface average power are different from the absolute value of the lateral differential value at any position in the rectangle. The absolute value of the value is larger.

以下に、回転面における上述の矩形の中心、即ち、Ｆ１を通る縦方向断面曲線において、Ｆ１からＮ１と同じ高さに至る縦方向断面度数変化の５０％を与える位置での各微分値の絶対値を示す。

縦方向断面度数の微分値の絶対値（単位：diopter/mm [屈折率：１．６９９として]）
横方向：０．０、縦方向：０．２４

表面非点収差量の微分値の絶対値（単位：diopter/mm [屈折率：１．６９９として]）
横方向：０．０、縦方向：０．２３

表面平均度数の微分値の絶対値（単位：diopter/mm [屈折率：１．６９９として]）
横方向：０．０、縦方向：０．１２ In the following, the absolute value of each differential value at a position giving 50% of the longitudinal cross-sectional frequency change from F1 to the same height as N1 in the center of the above-mentioned rectangle on the rotation surface, that is, the longitudinal cross-sectional curve passing through F1. Indicates the value.

The absolute value of the differential value of the longitudinal cross section power (unit: diopter / mm [refractive index: 1.699])
Horizontal direction: 0.0, vertical direction: 0.24

Absolute value of differential value of surface astigmatism (unit: diopter / mm [refractive index: 1.699])
Horizontal direction: 0.0, vertical direction: 0.23

Absolute value of differential value of surface average power (unit: diopter / mm [refractive index: 1.699])
Horizontal direction: 0.0, vertical direction: 0.12

上記の例では、説明を簡単にするために、回転面としたため、横方向の微分値がすべてゼロとなっている。また、主として視線とレンズ面とが直交しえないことに起因する非点収差の発生や度数の変化を、除去もしくは低減するための「補正作用」である非球面補正を、物体側表面か眼球側表面の一方、あるいは双方へ加えることが望ましい。しかし、非球面補正が加わると、横方向微分値も若干の値を有する。しかし、横方向微分値の絶対値よりも縦方向微分値の絶対値の方が大きいという特徴は保たれるようにする。
また、主として視線とレンズ面とが直交しえないことに起因する非点収差の発生や度数の変化を、除去もしくは低減するための「補正作用」である非球面補正を、物体側表面か眼球側表面の一方、あるいは双方へ加えることが望ましい。
尚、この変形例1は、本願明細書の実施例1の設計値を用い、それに非球面要素を取り除いたものを使用している。 In the above example, since the rotation surface is used for the sake of simplicity, the differential values in the horizontal direction are all zero. In addition, aspherical correction, which is a “correcting action” for removing or reducing astigmatism and power changes mainly due to the fact that the line of sight and the lens surface cannot be orthogonal, is performed on the object-side surface or eyeball. It is desirable to add to one or both of the side surfaces. However, when aspherical correction is applied, the lateral differential value also has a slight value. However, the feature that the absolute value of the vertical differential value is larger than the absolute value of the horizontal differential value is maintained.
In addition, aspherical correction, which is a “correcting action” for removing or reducing astigmatism and power changes mainly due to the fact that the line of sight and the lens surface cannot be orthogonal, is performed on the object-side surface or eyeball. It is desirable to add to one or both of the side surfaces.
In the first modification, the design value of the first embodiment of the present specification is used, and an aspherical element is removed therefrom.

次に、眼球側表面を設計する。眼球側表面は一般に複雑な形状をした曲面になるので、スプライン曲面を利用する。初期形状を球面として、光線追跡計算により透過収差分布を評価しながら、所望の透過収差分布、処方度数、累進帯長、打ち寄せが実現できるように、曲面のパラメータを変化させていくことで、眼球側表面を定義する。
こうして、物体側表面と眼球側表面が設計される。 Next, the eyeball side surface is designed. Since the eyeball side surface is generally a curved surface having a complicated shape, a spline curved surface is used. By changing the parameters of the curved surface so that the desired transmission aberration distribution, prescription power, progressive band length, and hitting can be realized while evaluating the transmission aberration distribution by ray tracing calculation with the initial shape as a spherical surface, the eyeball Define the side surface.
Thus, the object side surface and the eyeball side surface are designed.

（変形例２）
変形例２に係る両面非球面型累進屈折力レンズについて説明する。 (Modification 2)
A double-sided aspherical progressive-power lens according to Modification 2 will be described.

変形例２に係る両面非球面型累進屈折力レンズは、物体側表面である第1の屈折表面と、眼球側表面である第２の屈折表面とに、分割配分されている累進屈折力作用を備えた両面非球面型累進屈折力レンズであって、
前記第1の屈折表面において、近用度数測定位置Ｎ1における横方向の表面屈折力及び縦方向の表面屈折力をそれぞれＤＨｎ、ＤＶｎとするとき、
ＤＶｎ−ＤＨｎ＞ＡＤＤ／２となる関係式を満足させると共に、前記第1の屈折表面のＮ１における表面非点収差成分を前記第２の屈折表面にて相殺し、前記第1と第２の屈折表面とを合わせて、処方値に基づいた近用度数（Ｄｎ）を与える構成となっている。 The double-sided aspherical progressive-power lens according to the modified example 2 has a progressive power action that is divided and distributed between the first refractive surface that is the object-side surface and the second refractive surface that is the eyeball-side surface. A double-sided aspherical progressive addition lens equipped with,
In the first refracting surface, when the horizontal surface power and the vertical surface power at the near power measurement position N1 are DHn and DVn, respectively,
DVn−DHn> ADD / 2 is satisfied, the surface astigmatism component at N1 of the first refractive surface is canceled by the second refractive surface, and the first and second refractions are satisfied. Together with the surface, it is configured to give a near-use frequency (Dn) based on the prescription value.

さらに、上述した変形例２に係る両面非球面型累進屈折力レンズは、上述の構成に加え、
前記第1の屈折表面において、遠用度数測定位置Ｆ1における横方向の表面屈折力及び縦方向の表面屈折力をそれぞれＤＨｆ、ＤＶｆとし、
前記第1の屈折表面において、近用度数測定位置Ｎ1における横方向の表面屈折力及び縦方向の表面屈折力をそれぞれＤＨｎ、ＤＶｎとするとき、
ＤＨｆ＋ＤＨｎ＜ＤＶｆ＋ＤＶｎ、
かつ、
ＤＶｎ−ＤＶｆ＞ＡＤＤ／２、
かつＤＨｎ−ＤＨｆ＜ＡＤＤ／２となる関係式を満足させると共に、前記第1の屈折表面のＦ1及びＮ１における表面非点収差成分を前記第２の屈折表面にて相殺し、前記第1と第２の屈折表面とを合わせて処方値に基づいた遠用度数（Ｄｆ）と加入度数（ＡＤＤ）を与える構成となっている。 Furthermore, the double-sided aspherical progressive-power lens according to Modification 2 described above has the above-described configuration,
In the first refractive surface, the lateral surface power and the vertical surface power at the distance power measurement position F1 are DHf and DVf, respectively.
In the first refracting surface, when the horizontal surface power and the vertical surface power at the near power measurement position N1 are DHn and DVn, respectively,
DHf + DHn <DVf + DVn,
And,
DVn-DVf> ADD / 2,
And satisfying the relational expression of DHn−DHf <ADD / 2, and canceling out the surface astigmatism components at F1 and N1 of the first refractive surface by the second refractive surface, The distance power (Df) and the addition power (ADD) based on the prescription value are combined with the two refractive surfaces.

さらに、上述した変形例２に係る両面非球面型累進屈折力レンズは、上述の２つの構成のいずれかに加え、
前記第１の屈折表面が、前記遠用度数測定位置Ｆ１を通る一本の子午線を境に左右対称であり、前記第２の屈折表面が、この第２の屈折表面の遠用度数測定位置Ｆ２を通る一本の子午線を境に左右非対称であって、
かつ、
この第２の屈折表面の近用度数測定位置Ｎ２の配置は、所定の距離だけ鼻側に内寄せされており、近方視における眼の輻湊作用に対応した構成となっている。 Furthermore, the double-sided aspherical progressive-power lens according to Modification 2 described above, in addition to one of the two configurations described above,
The first refractive surface is symmetrical with respect to a meridian passing through the distance power measurement position F1, and the second refractive surface is a distance power measurement position F2 of the second refractive surface. Asymmetrical with a single meridian passing through
And,
The arrangement of the near-field power measurement position N2 on the second refractive surface is centered on the nose side by a predetermined distance, and has a configuration corresponding to the eye's convergence effect in near vision.

さらに、上述した変形例２に係る両面非球面型累進屈折力レンズは、上述の３つの構成のいずれかに加え、
前記第１の屈折表面が、前記遠用度数測定位置Ｆ１を通る一本の子午線を母線とした回転面であり、前記第２の屈折表面が、このこの第２の屈折表面の遠用度数測定位置Ｆ２を通る一本の子午線を境に左右非対称であって、
かつ、
この第２の屈折表面の近用度数測定位置Ｎ２の配置は、所定の距離だけ鼻側に内寄せされており、近方視における眼の輻湊作用に対応している構成となっている。 Furthermore, the double-sided aspherical progressive-power lens according to Modification 2 described above, in addition to any of the three configurations described above,
The first refracting surface is a rotating surface having a meridian passing through the distance power measurement position F1 as a generating line, and the second refracting surface is a distance power measurement of the second refracting surface. Asymmetrical with respect to one meridian passing through position F2,
And,
The arrangement of the near power measurement position N2 on the second refracting surface is centered on the nose side by a predetermined distance, and corresponds to the eye convergence action in near vision.

さらに、上述した変形例２に係る両面非球面型累進屈折力レンズは、上述の４つの構成のいずれかに加え、
前記第１の屈折表面において、前記遠用度数測定位置Ｆ１を通る水平方向断面曲線は、真円ではなく所定の屈折力変化を有しており、
かつ、
この水平方向断面曲線上の任意の位置における法線を含む垂直方向断面による断面曲線は、前記遠用度数測定位置Ｆ１を通る子午線と実質的に同一である構成となっている。 Furthermore, the double-sided aspherical progressive-power lens according to Modification 2 described above, in addition to any of the above four configurations,
In the first refracting surface, a horizontal cross-sectional curve passing through the distance power measurement position F1 has a predetermined refractive power change, not a perfect circle,
And,
A cross-sectional curve with a vertical cross section including a normal line at an arbitrary position on the horizontal cross-sectional curve is substantially the same as a meridian passing through the distance power measurement position F1.

さらに、上述した変形例２に係る両面非球面型累進屈折力レンズは、上述の５つの構成のいずれかに加え、
前記第1と第２の屈折表面とを合わせて処方値に基づいた遠用度数（Ｄｆ）と加入度数（ＡＤＤ）とを与えると共に、必要に応じてプリズム屈折力（Ｐｆ）を与える構成とする上で、
装用状態における視線とレンズ面とが直交しえないことに起因する非点収差や度数誤差の発生、及び周辺視野における像の歪みの発生のいずれか、もしくは全てを低減した構成となっている。
尚、必要に応じてプリズム屈折力（Ｐｆ）を与える設計手法は、例えば、特開平２００３−１２１８０１号等で公知であり、このような設計方法も組み合わせて用いることができる。 Furthermore, the double-sided aspherical progressive-power lens according to Modification 2 described above, in addition to any of the above five configurations,
The first and second refractive surfaces are combined to provide a distance power (Df) and an addition power (ADD) based on a prescription value, and a prism refractive power (Pf) is provided as necessary. Above,
This configuration reduces any or all of astigmatism and power error caused by the fact that the line of sight and the lens surface in the wearing state cannot be orthogonal to each other, and image distortion in the peripheral visual field.
Note that a design method for providing prism refractive power (Pf) as necessary is known, for example, in Japanese Patent Laid-Open No. 2003-121801, and such a design method can be used in combination.

上述した、構成を有する変形例２に係る両面非球面型累進屈折力レンズについて、図面を参照しながら説明する。
図５７は、変形例２における両面非球面型累進屈折力レンズの物体側表面である第１の屈折表面を表している。本説明において、図５にて白丸で示した、遠用度数測定位置Ｆ１を通る縦方向の断面曲線（実線）を子午線と呼ぶが、これは、「課題を解決するための手段」に記載した第３〜第５の構成等に記されている「遠用度数測定位置Ｆ１を通る子午線」のことである。また、破線で示されているのは水平断面曲線である。 The double-sided aspherical progressive-power lens according to Modification 2 having the above-described configuration will be described with reference to the drawings.
FIG. 57 shows a first refractive surface that is the object-side surface of the double-sided aspherical progressive-power lens in Modification 2. In this description, a vertical cross-sectional curve (solid line) passing through the distance power measurement position F1 indicated by a white circle in FIG. It is “the meridian passing through the distance power measurement position F1” described in the third to fifth configurations. Moreover, what is shown with a broken line is a horizontal sectional curve.

図５８は、図５７に実線で示されている子午線をレンズ側方から眺めた図である。図５８は、レンズ上方から下方にかけて曲率半径が漸減する区間を有しており、所謂累進的な表面屈折力変化を与えていることを示している。尚、Ｏ１は曲率中心点を表し、一点鎖線は、Ｏ１を通る回転軸を表す。 58 is a view of the meridian shown by the solid line in FIG. 57 as viewed from the side of the lens. FIG. 58 has a section in which the radius of curvature gradually decreases from the upper side to the lower side of the lens, and shows that a so-called progressive surface power change is given. O1 represents the center point of curvature, and the alternate long and short dash line represents the rotation axis passing through O1.

図５９は、図５７に点線で示されている水平断面曲線をレンズ上方から眺めた図であり、Ｏ１はこの水平断面曲線の曲率中心点を表す。即ち、図５９に点線で示されている水平断面曲線は円弧である。ここで、図５７に描かれた第１の屈折表面は、図５８で示した子午線を、Ｏ１を通る回転軸を中心に回転させて得ることが出来る。 FIG. 59 is a view of the horizontal cross section curve shown by the dotted line in FIG. 57 as viewed from above the lens, and O1 represents the center of curvature of the horizontal cross section curve. That is, the horizontal cross section curve shown by the dotted line in FIG. 59 is an arc. Here, the first refractive surface depicted in FIG. 57 can be obtained by rotating the meridian shown in FIG. 58 around the rotation axis passing through O1.

さらに加えて、本変形例２に係る第１の屈折表面の水平断面曲線は、必ずしも図５９の形態ばかりではなく、図６０〜図６２に示す形態をとることも出来るので、以下説明する。ここで、図６０は、図５９にて示したレンズ上方から眺めた水平断面曲線の第１変形例であり、図６１は、図５９にて示したレンズ上方から眺めた水平断面曲線の第２変形例であり、図６２は、図５９にて示したレンズ上方から眺めた水平断面曲線の第３変形例である。 In addition, the horizontal sectional curve of the first refracting surface according to the second modification example is not limited to the form shown in FIG. 59 but can take the form shown in FIGS. 60 to 62, and will be described below. Here, FIG. 60 is a first modification of the horizontal sectional curve viewed from above the lens shown in FIG. 59, and FIG. 61 is a second modified horizontal sectional curve viewed from above the lens shown in FIG. FIG. 62 shows a third modification of the horizontal sectional curve viewed from above the lens shown in FIG.

図６０において、Ｆ１から側方に離れるに従って、曲率半径が減少する水平断面曲線の例を表している。
図６１は、図６０とは逆に、Ｆ１から側方に離れるに従って曲率半径が増加する水平断面曲線の例を表している。
図６２は、図６０と図６１との例が、両者並存した水平断面曲線の例を表している。
更に、これら図６０〜図６２に示す形態をとった場合、それらの水平断面曲線の曲率半径の変化による屈折力変化の影響を相殺する作用を、第２の屈折表面において加えることも可能である。
この目的はレンズを通して見える像の形状倍率の変化を利用することにあり、水平断面曲線に沿っての形状倍率を装用者にとって好適なものにコントロールすることが出来る。特に図６２の形態をとることによって、装用時の鼻側と耳側の形状倍率をコントロールすることが可能となる。 FIG. 60 shows an example of a horizontal cross-sectional curve in which the radius of curvature decreases as the distance from F1 increases.
FIG. 61 shows an example of a horizontal cross-section curve in which the radius of curvature increases as the distance from F1 increases, as opposed to FIG.
FIG. 62 shows an example of a horizontal sectional curve in which the examples of FIGS. 60 and 61 coexist.
Further, when the forms shown in FIGS. 60 to 62 are adopted, it is also possible to add an effect of canceling the influence of the change in refractive power due to the change in the radius of curvature of the horizontal cross-section curve at the second refractive surface. .
The purpose is to use the change in the shape magnification of the image seen through the lens, and the shape magnification along the horizontal sectional curve can be controlled to be suitable for the wearer. In particular, by taking the form shown in FIG. 62, it is possible to control the shape magnification of the nose side and the ear side during wearing.

なお、説明を簡単にするため、図６０〜図６２に示す形態は、Ｆ１から側方に離れるに従って曲率半径が単調に減少または増加する例のみを挙げたが、一旦減少した後に増加したり、変化しない区間があったり、それらの逆変化の形態を組み合わせるなど、様々な変形例が考えられる。 In order to simplify the description, the forms shown in FIGS. 60 to 62 are only examples in which the radius of curvature monotonously decreases or increases as the distance from F1 increases. Various modifications are possible, such as there are sections that do not change, or combinations of their reverse changes.

（変形例３）
ここで、上述の構成とは異なり、スイープ面を有しない両面非球面型累進屈折力レンズの例を、図面を参照しながら説明する。
図６３及び図６４は、実施の形態の変形例３に係るレンズの物体側表面（第１面）における表面非点収差分布及び表面平均度数分布を示す図である。図面の標記方法は、前述した図４１及び図４２などのレンズの表面非点収差分布や表面平均度数分布を示す図と同様である。また、当該レンズ面は、遠用度数測定位置F1における横方向の表面屈折力及び縦方向の表面屈折力をそれぞれＤＨｆ、ＤＶｆとし、近用度数測定位置N1における横方向の表面屈折力及び縦方向の表面屈折力をそれぞれＤＨｎ、ＤＶｎとするとき、ＤＨｆ＝ＤＶｆ＝４．８７、ＤＨｎ＝６．１２、ＤＶｎ＝７．８７という特性を有している。尚、当該レンズは、遠用部の度数が０．００であり、加入度数（ＡＤＤ）が＋３．００の上平レンズである。当該レンズの物体側表面（第１面）がスイープ面でないことはＤＨｆ << ＤＨｎであることからも明らかである。また、ＤＶｎ−ＤＨｎ＝７．８７−６．１２＝１．７５の値は加入度数より少ないが加入度数の50％を超えており、本件発明の効果を得る事が出来る。
このように、ＤＨｎをＤＨｆより深いカーブにする目的は、当該レンズの物体側表面（第１面）を用いて強い正の遠用度数を製造しようとする場合、当該レンズの眼球側表面（第２面）が凸面形状となって、レンズ全体がメニスカス形状でなくなることを防ぐためである。
図６５及び図６６は、上述した実施の形態の変形例３に係るレンズの眼球側表面（第２面）における表面非点収差分布及び表面平均度数分布を示す図である。図面の標記方法は、前述した図４５及び図４６などのレンズの表面非点収差分布や表面平均度数分布を示す図と同様である。 (Modification 3)
Here, different from the above-described configuration, an example of a double-sided aspherical progressive-power lens having no sweep surface will be described with reference to the drawings.
63 and 64 are diagrams showing a surface astigmatism distribution and a surface average power distribution on the object-side surface (first surface) of the lens according to Modification 3 of the embodiment. The drawing marking method is the same as that for the surface astigmatism distribution and surface average power distribution of the lens shown in FIGS. 41 and 42 described above. Further, the lens surface has the horizontal surface power and the vertical surface power at the distance power measurement position F1 as DHf and DVf, respectively, and the horizontal surface power and the vertical direction at the near power measurement position N1. When the surface refractive power is DHn and DVn, DHf = DVf = 4.87, DHn = 6.12, and DVn = 7.87. The lens is an upper flat lens having a distance portion power of 0.00 and an addition power (ADD) of +3.00. It is clear from DHf << DHn that the object side surface (first surface) of the lens is not a sweep surface. Further, the value of DVn−DHn = 7.87−6.12 = 1.75 is less than the addition power, but exceeds 50% of the addition power, and the effect of the present invention can be obtained.
As described above, the purpose of making DHn a curve deeper than DHf is that when an object-side surface (first surface) of the lens is used to produce a strong positive dioptric power, the lens-side surface (first surface) This is for preventing the entire lens from becoming a meniscus shape.
65 and 66 are diagrams showing a surface astigmatism distribution and a surface average power distribution on the eyeball side surface (second surface) of the lens according to Modification 3 of the embodiment described above. The marking method of the drawing is the same as that shown in FIGS. 45 and 46 showing the surface astigmatism distribution and the surface average power distribution of the lens.

本発明における「所定の加入度数」の定義として、図６の如く、レンズメーターの開口部を物体側表面の遠用度数測定位置Ｆ１と近用度数測定位置Ｎ１に当てて測定した屈折力差とした場合の他に、レンズメーターの開口部を眼球側表面の遠用度数測定位置Ｆ２と近用度数測定位置Ｎ２に当てて測定した屈折力差とした場合、更にはレンズメーターの開口部を眼球側表面の遠用度数測定位置Ｆ２に当てて測定した屈折力と、眼球回旋中心位置を中心として回転させて近用度数測定位置Ｎ２に向けてＮ３で測定した屈折力との差とした場合、また各々の屈折力として特に水平方向の屈折力成分のみを用いた場合などがあり、
これらの内のいずれの定義を採用することも可能である。 As the definition of “predetermined addition power” in the present invention, as shown in FIG. 6, the difference in refractive power measured by applying the aperture of the lens meter to the distance power measurement position F1 and the near power measurement position N1 on the object side surface. In addition to the above case, when the refractive power difference is measured by applying the lens meter opening to the distance power measurement position F2 and the near power measurement position N2 on the eyeball side surface, the lens meter opening is further When the difference between the refractive power measured at the distance power measurement position F2 on the side surface and the refractive power measured at N3 toward the near power measurement position N2 by rotating around the center of rotation of the eyeball, In addition, there are cases where only the refractive power component in the horizontal direction is used as each refractive power,
Any of these definitions can be adopted.

眼鏡レンズ表面の各位置における各種の表面屈折力の説明図である。It is explanatory drawing of the various surface refractive power in each position of the spectacle lens surface. 眼球と視線とレンズとの位置関係の説明図である。It is explanatory drawing of the positional relationship of an eyeball, eyes | visual_axis, and a lens. プリズムの倍率Ｍγに関する説明図であってプラスレンズとマイナスレンズによる違いや主としてレンズの下部である近用部を用いて眺めた場合の倍率の違いに関する説明図である。It is explanatory drawing regarding magnification Mγ of a prism, Comprising: It is explanatory drawing regarding the difference between magnifications at the time of seeing using the near part which is mainly the lower part of a lens and the difference between a plus lens and a minus lens. プリズムの倍率Ｍγに関する説明図であってプラスレンズとマイナスレンズによる違いや主としてレンズの下部である近用部を用いて眺めた場合の倍率の違いに関する説明図である。It is explanatory drawing regarding magnification Mγ of a prism, Comprising: It is explanatory drawing regarding the difference between magnifications at the time of seeing using the near part which is mainly the lower part of a lens and the difference between a plus lens and a minus lens. プリズムの倍率Ｍγに関する説明図であってプラスレンズとマイナスレンズによる違いや主としてレンズの下部である近用部を用いて眺めた場合の倍率の違いに関する説明図である。It is explanatory drawing regarding magnification Mγ of a prism, Comprising: It is explanatory drawing regarding the difference between magnifications at the time of seeing using the near part which is mainly the lower part of a lens and the difference between a plus lens and a minus lens. プリズムの倍率Ｍγに関する説明図であってプラスレンズとマイナスレンズによる違いや主としてレンズの下部である近用部を用いて眺めた場合の倍率の違いに関する説明図である。It is explanatory drawing regarding magnification Mγ of a prism, Comprising: It is explanatory drawing regarding the difference between magnifications at the time of seeing using the near part which is mainly the lower part of a lens and the difference between a plus lens and a minus lens. プリズムの倍率Ｍγに関する説明図であってプラスレンズとマイナスレンズによる違いや主としてレンズの下部である近用部を用いて眺めた場合の倍率の違いに関する説明図である。It is explanatory drawing regarding magnification Mγ of a prism, Comprising: It is explanatory drawing regarding the difference between magnifications at the time of seeing using the near part which is mainly the lower part of a lens and the difference between a plus lens and a minus lens. プリズムの倍率Ｍγに関する説明図であってプラスレンズとマイナスレンズによる違いや主としてレンズの下部である近用部を用いて眺めた場合の倍率の違いに関する説明図である。It is explanatory drawing regarding magnification Mγ of a prism, Comprising: It is explanatory drawing regarding the difference between magnifications at the time of seeing using the near part which is mainly the lower part of a lens and the difference between a plus lens and a minus lens. 累進屈折力レンズの光学的レイアウトの説明図であって累進屈折力レンズを物体側表面から眺めた正面図である。It is explanatory drawing of the optical layout of a progressive-power lens, Comprising: It is the front view which looked at the progressive-power lens from the object side surface. 累進屈折力レンズの光学的レイアウトの説明図であって縦方向の断面を表す側面図である。It is explanatory drawing of the optical layout of a progressive-power lens, and is a side view showing the cross section of a vertical direction. 累進屈折力レンズの光学的レイアウトの説明図であって横方向の断面を表す立面図である。It is explanatory drawing of the optical layout of a progressive-power lens, and is an elevational view showing the cross section of a horizontal direction. 「加入度数」の定義の違いを示す説明図である。It is explanatory drawing which shows the difference in the definition of "addition frequency". 実施例１、４、５、６と各々の度数に対応した従来技術Ａ，Ｂ，Ｃの「表面屈折力」と「特定の視線方向に対する厳密な倍率計算結果」を表１−１及び表１−２にまとめて示した図である。Tables 1-1 and 1 show "surface refractive power" and "strict magnification calculation results for a specific line-of-sight direction" of the conventional techniques A, B, and C corresponding to Examples 1, 4, 5, and 6, respectively. FIG. 実施例２、７と各々の度数に対応した従来技術Ａ，Ｂ，Ｃの「表面屈折力」と「特定の視線方向に対する厳密な倍率計算結果」を表２−１及び表２−２にまとめて示した図である。Tables 2-1 and 2-2 summarize the “surface refractive power” and “exact magnification calculation results for a specific line-of-sight direction” of the conventional techniques A, B, and C corresponding to Examples 2 and 7 and respective frequencies. FIG. 実施例３とその度数に対応した従来技術Ａ，Ｂ，Ｃの「表面屈折力」と「特定の視線方向に対する厳密な倍率計算結果」を表３−１及び表３−２にまとめて示した図である。Table 3-1 and Table 3-2 collectively show “surface refractive power” and “strict magnifying power calculation results for a specific line-of-sight direction” of the prior art A, B, and C corresponding to Example 3 and the frequency thereof. FIG. 実施例１及び実施例２の表面屈折力分布を表すグラフ１−１、１−２、２−１、２−２を示す図である。It is a figure which shows the graph 1-1, 1-2, 2-1, 2-2 showing the surface refractive power distribution of Example 1 and Example 2. FIG. 実施例３の表面屈折力分布を表すグラフ３−１、３−２を示す図である。FIG. 6 is a diagram illustrating graphs 3-1 and 3-2 representing a surface refractive power distribution of Example 3. 実施例４〜６の表面屈折力分布を表すグラフ４−１、４−２、５−１、５−２、６−１、６−２を示す図である。It is a figure which shows the graph 4-1, 4-2, 5-1, 5-2, 6-1, 6-2 showing the surface refractive power distribution of Examples 4-6. 実施例７の表面屈折力分布を表すグラフ７−１、７−２を示す図である。It is a figure which shows the graphs 7-1 and 7-2 showing the surface refractive power distribution of Example 7. FIG. 従来技術例Ａ，Ｂ，Ｃの表面屈折力分布を表すグラフＡ−１、Ａ−２、Ｂ−１、Ｂ−２、Ｃ−１、Ｃ−２を示す図である。It is a figure which shows graph A-1, A-2, B-1, B-2, C-1, and C-2 showing the surface refractive power distribution of prior art examples A, B, and C. 実施例１とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ１−３−Ｍｓｖを示す図である。Graph 1 representing the result obtained by performing strict magnification calculation on the magnification distribution when viewing the lenses of Example 1 and three types of conventional examples A, B, and C corresponding to the power along the main line of sight It is a figure which shows 3-Msv. 実施例１とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ１−３−Ｍｓｈを示す図である。Graph 1 representing the result obtained by performing strict magnification calculation on the magnification distribution when viewing the lenses of Example 1 and three types of conventional examples A, B, and C corresponding to the power along the main line of sight It is a figure which shows 3-Msh. 実施例１とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ１−３−Ｍｐｖを示す図である。Graph 1 representing the result obtained by performing strict magnification calculation on the magnification distribution when viewing the lenses of Example 1 and three types of conventional examples A, B, and C corresponding to the power along the main line of sight It is a figure which shows 3-Mpv. 実施例１とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ１−３−Ｍｐｈを示す図である。Graph 1 representing the result obtained by performing strict magnification calculation on the magnification distribution when viewing the lenses of Example 1 and three types of conventional examples A, B, and C corresponding to the power along the main line of sight It is a figure which shows 3-Mph. 実施例１とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ１−３−Ｍγｖを示す図である。Graph 1 representing the result obtained by performing strict magnification calculation on the magnification distribution when viewing the lenses of Example 1 and three types of conventional examples A, B, and C corresponding to the power along the main line of sight It is a figure which shows 3-Mγv. 実施例１とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ１−３−Ｍγｈを示す図である。Graph 1 representing the result obtained by performing strict magnification calculation on the magnification distribution when viewing the lenses of Example 1 and three types of conventional examples A, B, and C corresponding to the power along the main line of sight It is a figure which shows 3-Mγh. 実施例１とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ１−３−ＳＭｖを示す図である。Graph 1 representing the result obtained by performing strict magnification calculation on the magnification distribution when viewing the lenses of Example 1 and three types of conventional examples A, B, and C corresponding to the power along the main line of sight It is a figure which shows 3-SMv. 実施例１とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ１−３−ＳＭｈを示す図である。Graph 1 representing the result obtained by performing strict magnification calculation on the magnification distribution when viewing the lenses of Example 1 and three types of conventional examples A, B, and C corresponding to the power along the main line of sight It is a figure which shows 3-SMh. 実施例２とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ２−３−Ｍｓｖを示す図である。Graph 2 showing a result obtained by performing a strict magnification calculation on a magnification distribution when the lenses of Example 2 and three types of conventional examples A, B, and C corresponding to the frequency are viewed along the main line of sight It is a figure which shows 3-Msv. 実施例２とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ２−３−Ｍｓｈを示す図である。Graph 2 showing a result obtained by performing a strict magnification calculation on a magnification distribution when the lenses of Example 2 and three types of conventional examples A, B, and C corresponding to the frequency are viewed along the main line of sight It is a figure which shows 3-Msh. 実施例２とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ２−３−Ｍｐｖを示す図である。Graph 2 showing a result obtained by performing a strict magnification calculation on a magnification distribution when the lenses of Example 2 and three types of conventional examples A, B, and C corresponding to the frequency are viewed along the main line of sight It is a figure which shows 3-Mpv. 実施例２とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ２−３−Ｍｐｈを示す図である。Graph 2 showing a result obtained by performing a strict magnification calculation on a magnification distribution when the lenses of Example 2 and three types of conventional examples A, B, and C corresponding to the frequency are viewed along the main line of sight It is a figure which shows 3-Mph. 実施例２とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ２−３−Ｍγｖを示す図である。Graph 2 showing a result obtained by performing a strict magnification calculation on a magnification distribution when the lenses of Example 2 and three types of conventional examples A, B, and C corresponding to the frequency are viewed along the main line of sight It is a figure which shows 3-Mγv. 実施例２とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ２−３−Ｍγｈを示す図である。Graph 2 showing a result obtained by performing a strict magnification calculation on a magnification distribution when the lenses of Example 2 and three types of conventional examples A, B, and C corresponding to the frequency are viewed along the main line of sight It is a figure which shows 3-Mγh. 実施例２とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ２−３−ＳＭｖを示す図である。Graph 2 showing a result obtained by performing a strict magnification calculation on a magnification distribution when the lenses of Example 2 and three types of conventional examples A, B, and C corresponding to the frequency are viewed along the main line of sight It is a figure which shows 3-SMv. 実施例２とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ２−３−ＳＭｈを示す図である。Graph 2 showing a result obtained by performing a strict magnification calculation on a magnification distribution when the lenses of Example 2 and three types of conventional examples A, B, and C corresponding to the frequency are viewed along the main line of sight It is a figure which shows 3-SMh. 実施例３とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ３−３−Ｍｓｖを示す図である。Graph 3 showing a result obtained by performing a strict magnification calculation on the magnification distribution when the lenses of Example 3 and three types of conventional examples A, B, and C corresponding to the frequency are viewed along the main gazing line. It is a figure which shows 3-Msv. 実施例３とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ３−３−Ｍｓｈを示す図である。Graph 3 showing a result obtained by performing a strict magnification calculation on the magnification distribution when the lenses of Example 3 and three types of conventional examples A, B, and C corresponding to the frequency are viewed along the main gazing line. It is a figure which shows 3-Msh. 実施例３とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ３−３−Ｍｐｖを示す図である。Graph 3 showing a result obtained by performing a strict magnification calculation on the magnification distribution when the lenses of Example 3 and three types of conventional examples A, B, and C corresponding to the frequency are viewed along the main gazing line. It is a figure which shows 3-Mpv. 実施例３とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ３−３−Ｍｐｈを示す図である。Graph 3 showing a result obtained by performing a strict magnification calculation on the magnification distribution when the lenses of Example 3 and three types of conventional examples A, B, and C corresponding to the frequency are viewed along the main gazing line. It is a figure which shows 3-Mph. 実施例３とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ３−３−Ｍγｖを示す図である。Graph 3 showing a result obtained by performing a strict magnification calculation on the magnification distribution when the lenses of Example 3 and three types of conventional examples A, B, and C corresponding to the frequency are viewed along the main gazing line. It is a figure which shows 3-Mγv. 実施例３とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ３−３−Ｍγｈを示す図である。Graph 3 showing a result obtained by performing a strict magnification calculation on the magnification distribution when the lenses of Example 3 and three types of conventional examples A, B, and C corresponding to the frequency are viewed along the main gazing line. It is a figure which shows 3-Mγh. 実施例３とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ３−３−ＳＭｖを示す図である。Graph 3 showing a result obtained by performing a strict magnification calculation on the magnification distribution when the lenses of Example 3 and three types of conventional examples A, B, and C corresponding to the frequency are viewed along the main gazing line. It is a figure which shows 3-SMv. 実施例３とその度数に対応した３種類の従来例Ａ，Ｂ，Ｃのレンズを主注視線に沿って眺めたときの倍率分布を厳密な倍率計算を行って求めた結果を表すグラフ３−３−ＳＭｈを示す図である。Graph 3 showing a result obtained by performing a strict magnification calculation on the magnification distribution when the lenses of Example 3 and three types of conventional examples A, B, and C corresponding to the frequency are viewed along the main gazing line. It is a figure which shows 3-SMh. 実施例１に係るレンズの透過状態における非点収差分布を示す図である。FIG. 6 is a diagram illustrating an astigmatism distribution in a transmission state of a lens according to Example 1. 実施例１に係るレンズの透過状態における平均度数分布を示す図である。6 is a diagram illustrating an average power distribution in a transmission state of a lens according to Example 1. FIG. 実施例１に係るレンズの凸面側の屈折表面における非点収差分布を示す図である。FIG. 6 is a diagram illustrating an astigmatism distribution on the refractive surface on the convex surface side of the lens according to Example 1; 実施例１に係るレンズの凸面側の屈折表面における平均度数分布を示す図である。6 is a diagram showing an average power distribution on a refractive surface on the convex surface side of the lens according to Example 1. FIG. 実施例１に係るレンズの凸面側の屈折表面における横（水平）方向の度数分布を示す図である。6 is a diagram showing a frequency distribution in a horizontal (horizontal) direction on a refractive surface on the convex surface side of the lens according to Example 1. FIG. 実施例１に係るレンズの凸面側の屈折表面における縦（垂直）方向の度数分布を示す図である。6 is a diagram showing a frequency distribution in a vertical (vertical) direction on a refractive surface on the convex surface side of the lens according to Example 1. FIG. 実施例１に係るレンズの凹面側の屈折表面における非点収差分布を示す図である。6 is a diagram showing an astigmatism distribution on a refractive surface on the concave surface side of the lens according to Example 1. FIG. 実施例１に係るレンズの凹面側の屈折表面における平均度数分布を示す図である。6 is a diagram showing an average power distribution on a refractive surface on the concave surface side of the lens according to Example 1. FIG. 実施例１に係るレンズの凹面側の屈折表面における横（水平）方向の度数分布を示す図である。6 is a diagram showing a frequency distribution in a horizontal (horizontal) direction on a refractive surface on the concave surface side of the lens according to Example 1. FIG. 実施例１に係るレンズの凹面側の屈折表面における縦（垂直）方向の度数分布を示す図である。6 is a diagram illustrating a frequency distribution in a vertical (vertical) direction on a concave refractive surface of a lens according to Example 1. FIG. 従来の技術に係るレンズの凸面側の屈折表面における非点収差分布を示す図である。It is a figure which shows the astigmatism distribution in the refractive surface of the convex surface side of the lens which concerns on a prior art. 従来の技術に係るレンズの凸面側の屈折表面における平均度数分布を示す図である。It is a figure which shows the average frequency distribution in the refractive surface of the convex surface side of the lens which concerns on a prior art. 従来の技術に係るレンズの凸面側の屈折表面における横（水平）方向の度数分布を示す図である。It is a figure which shows the frequency distribution of the horizontal (horizontal) direction in the refractive surface of the convex surface side of the lens which concerns on a prior art. 従来の技術に係るレンズの凸面側の屈折表面における縦（垂直）方向の度数分布を示す図である。It is a figure which shows the frequency distribution of the vertical (vertical) direction in the refractive surface of the convex surface side of the lens which concerns on a prior art. 実施の形態の変形例１に係るレンズの物体側表面における縦（垂直）方向の度数分布を示す図である。It is a figure which shows the frequency distribution of the vertical (vertical) direction in the object side surface of the lens which concerns on the modification 1 of embodiment. 実施の形態の変形例１に係るレンズの物体側表面における表面非点収差分布を示す図である。It is a figure which shows the surface astigmatism distribution in the object side surface of the lens which concerns on the modification 1 of embodiment. 実施の形態の変形例１に係るレンズの物体側表面における表面平均度数分布を示す図である。It is a figure which shows the surface average frequency distribution in the object side surface of the lens which concerns on the modification 1 of embodiment. 実施の形態の変形例１に係るレンズの物体側表面における縦（垂直）方向の度数変化を示す図である。It is a figure which shows the frequency change of the vertical (vertical) direction in the object side surface of the lens which concerns on the modification 1 of embodiment. 実施の形態の変形例２に係るレンズの一般的なスイープ面の例を示す図である。It is a figure which shows the example of the general sweep surface of the lens which concerns on the modification 2 of embodiment. 図５７にて実線で示されている子午線を、レンズ側方から眺めた図である。It is the figure which looked at the meridian shown with the continuous line in FIG. 57 from the lens side. 図５７にて点線で示されている掃引線を、レンズ上方から眺めた図である。It is the figure which looked at the sweep line shown with the dotted line in FIG. 57 from the lens upper direction. 図５９にて示したレンズ上方から眺めた掃引線の第１変形例である。It is the 1st modification of the sweep line seen from the lens upper part shown in FIG. 図５９にて示したレンズ上方から眺めた掃引線の第２変形例である。FIG. 60 is a second modification of the sweep line viewed from above the lens shown in FIG. 59. FIG. 図５９にて示したレンズ上方から眺めた掃引線の第３変形例である。FIG. 60 is a third modification of the sweep line viewed from above the lens shown in FIG. 59. FIG. 実施の形態の変形例３に係るレンズの物体側表面における表面非点収差分布を示す図である。It is a figure which shows the surface astigmatism distribution in the object side surface of the lens which concerns on the modification 3 of embodiment. 実施の形態の変形例３に係るレンズの物体側表面における表面平均度数分布を示す図である。It is a figure which shows the surface average frequency distribution in the object side surface of the lens which concerns on the modification 3 of embodiment. 実施の形態の変形例３に係るレンズの眼球側表面における表面非点収差分布を示す図である。It is a figure which shows the surface astigmatism distribution in the eyeball side surface of the lens which concerns on the modification 3 of embodiment. 実施の形態の変形例３に係るレンズの眼球側表面における表面平均度数分布を示す図である。It is a figure which shows the surface average frequency distribution in the eyeball side surface of the lens which concerns on the modification 3 of embodiment.

Claims

A double-sided aspherical progressive-power lens having a progressive-power action divided and distributed into a first refractive surface that is an object-side surface and a second refractive surface that is an eyeball-side surface,
In the first refractive surface, the horizontal surface power and the vertical surface power at the distance power measurement position F1 are DHf and DVf, respectively.
In the first refracting surface, when the horizontal surface power and the vertical surface power at the near power measurement position N1 are DHn and DVn, respectively,
DVn-DVf> ADD / 2
Is satisfied, and the surface astigmatism components at F1 and N1 of the first refractive surface are canceled by the second refractive surface, and the first and second refractive surfaces are combined. To give the addition power (ADD) based on the prescription value,
And,
In the longitudinal section curve passing through F1, two horizontal lines located ± 4 mm in the longitudinal direction centering on the position giving 50% of the longitudinal section frequency change from F1 to the same height as N1, and the longitudinal line passing through F1 At an arbitrary position within a rectangle surrounded by two vertical lines located ± 15 mm horizontally from the direction straight line,
A double-sided aspherical progressive-power lens characterized in that the absolute value of the longitudinal differential value of the differential value of the surface longitudinal cross-sectional power at the first refractive surface is larger than the absolute value of the lateral differential value .

A double-sided aspherical progressive-power lens having a progressive-power action divided and distributed into a first refractive surface that is an object-side surface and a second refractive surface that is an eyeball-side surface,
In the first refractive surface, the horizontal surface power and the vertical surface power at the distance power measurement position F1 are DHf and DVf, respectively.
In the first refracting surface, when the horizontal surface power and the vertical surface power at the near power measurement position N1 are DHn and DVn, respectively,
DVn-DVf> ADD / 2
Is satisfied, and the surface astigmatism components at F1 and N1 of the first refractive surface are canceled by the second refractive surface, and the first and second refractive surfaces are combined. To give the addition power (ADD) based on the prescription value,
And,
In the longitudinal section curve passing through F1, two horizontal lines located ± 4 mm in the longitudinal direction centering on the position giving 50% of the longitudinal section frequency change from F1 to the same height as N1, and the longitudinal line passing through F1 At an arbitrary position within a rectangle surrounded by two vertical lines located ± 15 mm horizontally from the direction straight line,
The differential value of the amount of surface astigmatism on the first refractive surface is greater in the absolute value of the longitudinal differential value than in the absolute value of the lateral differential value,
And,
At any position within the rectangle,
The double-sided aspherical progressive-power lens according to claim 1, wherein the differential value of the surface average power on the first refractive surface has a larger absolute value of the longitudinal differential value than an absolute value of the lateral differential value.

A design method of a double-sided aspherical progressive-power lens having a progressive-power action divided and distributed into a first refractive surface that is an object-side surface and a second refractive surface that is an eyeball-side surface, In the first refractive surface, the lateral surface power and the longitudinal surface power at the distance power measurement position F1 are DHf and DVf, respectively.
In the first refracting surface, when the horizontal surface power and the vertical surface power at the near power measurement position N1 are DHn and DVn, respectively,
DVn-DVf> ADD / 2
Is satisfied, and the surface astigmatism components at F1 and N1 of the first refractive surface are canceled by the second refractive surface, and the first and second refractive surfaces are combined. To give the addition power (ADD) based on the prescription value,
And,
In the longitudinal section curve passing through F1, two horizontal lines located ± 4 mm in the longitudinal direction centering on the position giving 50% of the longitudinal section frequency change from F1 to the same height as N1, and the longitudinal line passing through F1 At an arbitrary position within a rectangle surrounded by two vertical lines located ± 15 mm horizontally from the direction straight line,
The differential value of the surface longitudinal direction cross-sectional power at the first refractive surface is such that the absolute value of the longitudinal differential value is larger than the absolute value of the lateral differential value, and the double-sided aspherical progressive power is characterized in that Lens design method.

A design method of a double-sided aspherical progressive-power lens having a progressive-power action divided and distributed into a first refractive surface that is an object-side surface and a second refractive surface that is an eyeball-side surface, In the first refractive surface, the lateral surface power and the longitudinal surface power at the distance power measurement position F1 are DHf and DVf, respectively.
In the first refracting surface, when the horizontal surface power and the vertical surface power at the near power measurement position N1 are DHn and DVn, respectively,
DVn-DVf> ADD / 2
Is satisfied, and the surface astigmatism components at F1 and N1 of the first refractive surface are canceled by the second refractive surface, and the first and second refractive surfaces are combined. To give the addition power (ADD) based on the prescription value,
And,
In the longitudinal section curve passing through F1, two horizontal lines located ± 4 mm in the longitudinal direction centering on the position giving 50% of the longitudinal section frequency change from F1 to the same height as N1, and the longitudinal line passing through F1 At an arbitrary position within a rectangle surrounded by two vertical lines located ± 15 mm horizontally from the direction straight line,
The differential value of the amount of surface astigmatism on the first refractive surface is greater in the absolute value of the longitudinal differential value than in the absolute value of the lateral differential value,
And,
In an arbitrary position within the rectangle, the differential value of the surface average power at the first refractive surface is larger in the absolute value of the longitudinal differential value than the absolute value of the horizontal differential value. Design method for a double-sided aspherical progressive-power lens.