JPH0441322B2 - - Google Patents
Info
- Publication number
- JPH0441322B2 JPH0441322B2 JP58103350A JP10335083A JPH0441322B2 JP H0441322 B2 JPH0441322 B2 JP H0441322B2 JP 58103350 A JP58103350 A JP 58103350A JP 10335083 A JP10335083 A JP 10335083A JP H0441322 B2 JPH0441322 B2 JP H0441322B2
- Authority
- JP
- Japan
- Prior art keywords
- lens
- lens group
- amount
- group
- object side
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 230000014509 gene expression Effects 0.000 claims description 17
- 230000005499 meniscus Effects 0.000 claims description 6
- 230000004075 alteration Effects 0.000 description 29
- 206010010071 Coma Diseases 0.000 description 8
- 201000009310 astigmatism Diseases 0.000 description 8
- 230000006866 deterioration Effects 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 238000003384 imaging method Methods 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical group [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 230000003292 diminished effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
Classifications
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B9/00—Optical objectives characterised both by the number of the components and their arrangements according to their sign, i.e. + or -
- G02B9/62—Optical objectives characterised both by the number of the components and their arrangements according to their sign, i.e. + or - having six components only
Description
本発明は、無限遠から等倍付近までの物体を連
続的に撮影することの出来る大口径マクロレンズ
に関するものである。
従来マクロレンズは、一般の撮影用レンズが無
限遠近傍で最良の収差補正がなされているのに対
し、撮影距離変化による収差劣下を考慮して、撮
影倍率１／10倍付近で収差補正されている。しか
しながら、上記のように最良収差補正を近距離に
設定しても、撮影倍率をさらに高くしていくにつ
れ、球面収差、コマ収差及び非点収差の劣化は頭
顕になり大口径マクロレンズの実現を困難なもの
にしていた。これに対して、上記近距離フオーカ
シングに伴う収差劣下をいわゆるフローテイング
機構を備えて、補正することにより大口径マクロ
レンズを実現したものが知られている。このよう
なフローテイング機構を設けることにより、球面
収差、コマ収差の補正は、有利となるが、マクロ
レンズとして重要な歪曲収差の変動及び非点隔差
をある程度許容する傾向となる。一方、無限遠か
ら等倍付近までの物体を連続的に撮影できるよう
にするためには、フオーカシングに際して、通常
そのレンズの焦点距離相当のフローテイング繰り
出し量が必要となり、レンズ系のみでは、コンパ
クトであつても、そのフオーカシング繰り出し量
の大きさから鏡銅構成が複雑となり、製品全体と
してコンパクトなレンズが実現できなかつた。
本発明は、無限遠から等倍付近までの広い撮影
領域において、歪曲収差の変動が小さくかつ球面
収差、コマ収差と非点収差とのバランスが良好に
補正されているとともに、フオーカシング繰出量
が小さくコンパクトな大口径マクロレンズ系を提
供することを目的とするものである。
本発明の大口径マクロレンズは、第１図から第
３図の如く物体側より順に正の屈折力を有する第
１レンズ群、正の屈折力を有する第２レンズ群
、そして負の屈折力を有する第３レンズ群の
３群から構成され、無限遠物体から近接物体への
フオーカシングに際して、前記第１レンズ群から
第３レンズ群をいずれも物体側に移動させ、この
とき前記第１レンズ群と第２レンズ群間の空気間
隔及び前記第２レンズ群と第３レンズ群間の空気
間隔をともに増大させる構成を有している。
本発明は上記のようにして、第１レンズ群と第
２レンズ群との間の空気間隔を増大しつつこれら
を繰り出すことにより、球面収差、特にコマ収差
の劣化を補正するとともに第１レンズ群と第２レ
ンズ群との繰り出しによる歪曲収差の負方向への
増加と、非点収差のバランスを第２レンズ群と第
３レンズ群との間の空気間隔の増大により補正し
ている。すなわち、第１レンズ群と第２レンズ群
間のフローテイングで主に球面収差とコマ収差の
補正を行うとともに、第２レンズ群と第３レンズ
群間のフローテイングで主に歪曲収差と非点収差
の補正を行うことにより、諸収差を分離して補正
できるのでより良好な補正が可能となつている。
又本発明では、所定の屈折力を有する負の第３
レンズ群を最も像面側に配し、正の第１レンズ群
及び正の第２レンズ群との空気間隔を増大させて
近接物体にフオーカシングすることにより、第１
レンズ群及び第２レンズ群のフオーカシング移動
量をより小さくしている。
本発明は以上の基本的構成を有するとともに、
次の条件を満足することを特徴とする。
(1) −14＜3／＜−３
(2) 0.1＜m3／m2＜0.8
但し、は全系の焦点距離、3は第３レンズ群
の焦点距離、m2は第２レンズ群の移動量、m3は
第３レンズ群の移動量である。
条件式(1)は第３レンズ群の屈折力を規定するも
ので、条件式(2)と伴に、無限遠時から近接時の第
１・第２レンズ群の移動量に関連している。すな
わち条件式(1)の下限を越えると、第３レンズ群の
屈折力が弱くなりすぎ、無限遠時から近接時（等
倍付近まで）の第１・第２レンズ群の移動量を小
さくし、製品全体をコンパクトな型で実現したい
という本発明の目的からはずれることになる。一
方その上限を越えると球面収差及び非点収差の補
正が困難となる。
条件式(2)は、第３レンズ群の第１・第２レンズ
群に対する移動量比を規定するもので、条件式(1)
と伴に無限遠時から近接時の第１・第２レンズ群
の移動量に関連すると同時に、近接時の歪曲収差
の変動及び非点収差の補正に関連している。すな
わち、条件式(2)の上限を越えると、前記の条件式
(1)の場合と同様に、無限遠時から近接時の第１・
第２レンズ群の移動量を小さくすることが出来な
くなると伴に、歪曲収差の変動を小さくすること
が困難となる。一方、条件(2)の下限を越えると条
件式(1)の元での非点収差の補正が困難となるとと
もに等倍付近までフオーカシングしようとする第
３レンズ群に必要な有効径が大きくなりすぎる。
なお、第１レンズ群と第２レンズ群の無限時か
ら近接時への移動量比も前記条件式(1)(2)の元で
は、球面収差とコマ収差の良好な補正をするには
その妥当な値が決まつてくるが、具体的には、以
下の条件式に従うのが望ましい。
(3) 1.14＜m1／m2＜1.22
但し、m1は第１レンズ群の移動量である。
条件式(3)は、無限時から近接時の球面収差とコ
マ収差の補正に関連している。すなわち、その上
限を越えると近接時の球面収差が補正不足とな
り、一方その下限を越えると像面性を考慮した状
態でのコマ収差の補正が困難となる。
本発明の実施にあたつては、さらに以下の条件
式に従うのが望ましい。
(4) 0.1＜ΔdA／ΔdB＜0.5
但し、ΔdA第１レンズ群と第２レンズ群の間
の空気間隔の変化量、ΔdB第２レンズ群と第３
レンズ群の間の空気間隔の変化量である。
(5) 0.05＜m3／m1＜0.7
上記の条件式(4)はフオーカシングにおいてとも
に増大する第１・２レンズ群及び、第２・３レン
ズ群間の空気間隔の増大比を規定するもので上限
値を越えると近接フオーカシングの際の球面収差
とコマ収差変動を補正することが困難となり、一
方、下限値を越えると球面収差と比点収差の変動
をバランスよく補正するのが困難となる。
また、条件式(5)は条件式(1)、(2)とも関連し、そ
の下限を越えると第３群の有効径を大きく取らな
ければならなくなるとともに、像面彎曲の変動の
補正が不充分となる。一方、条件式(5)の上限を越
えると、第１・第２レンズ群のフオーカシング繰
出量を小さくする効果が薄れるとともに歪曲の変
動を補正するのが困難となる。
本発明の具体的なレンズ構成としては、下記の
ものが望ましい。すなわち、物体側より順に前記
第１レンズ群は、正レンズ、物体側に凸面を向け
た正メニスカスレンズ及び負レンズより構成し、
前記第２レンズ群は曲率の強い面を物体側に向け
た負レンズと曲率の強い面を像側に向けた正レン
ズとを貼り合わせて成る接合レンズ及び曲率の強
い面を像側に向けた正レンズより構成するととも
に、前記第３レンズ群は物体側に凸面を向けた負
のメニスカスレンズより構成する。
なお、上記において第３レンズ群を構成する負
のメニスカスレンズは条件式(2)から明らかなよう
にその屈折力は弱く温度変合によるレンズバック
の変動の影響が小さいのでプラスチツクレンズで
構成することが可能である。（実施例３参照）ま
た屈折力の弱いメニスカスレンズという第３レン
ズ群の具体的形状は、これをオプラスチツクで形
成するならば、その製造も容易となる。
次に本発明の実施例の無限遠フオーカス状態の
諸元を示す。実施例においてriは物体側から順に
第ｉ番目の面の曲率半径、diは物体側より順に第
ｉ番目の軸上間隔、Niとνiはそれぞれ物体側か
ら順に第ｉ番目のレンズの屈折率とアツベ数であ
る。
The present invention relates to a large-diameter macro lens that can continuously photograph objects from infinity to near the same magnification. Conventional macro lenses have aberrations that are best corrected near infinity for general photography lenses, but in consideration of aberration deterioration due to changes in shooting distance, aberrations are corrected at around 1/10x magnification. ing. However, even if the best aberration correction is set to a short distance as described above, as the imaging magnification is further increased, the deterioration of spherical aberration, coma aberration, and astigmatism becomes more noticeable, making it possible to create a large-diameter macro lens. was making it difficult. On the other hand, it is known that a large-diameter macro lens is realized by providing a so-called floating mechanism to correct the aberration degradation caused by short-distance focusing. By providing such a floating mechanism, it is advantageous to correct spherical aberration and coma aberration, but it tends to tolerate fluctuations in distortion aberration and astigmatism to some extent, which are important as a macro lens. On the other hand, in order to be able to continuously photograph objects from infinity to near the same magnification, a floating amount equivalent to the focal length of the lens is usually required for focusing, and the lens system alone is not compact and However, due to the large focusing extension amount, the mirror copper structure was complicated, making it impossible to create a compact lens as a whole. The present invention has a small variation in distortion aberration and a good balance between spherical aberration, coma aberration, and astigmatism in a wide imaging range from infinity to near the same magnification, and has a small focusing extension and is compact. The purpose of this invention is to provide a large-diameter macro lens system with a large diameter. As shown in FIGS. 1 to 3, the large-diameter macro lens of the present invention includes, in order from the object side, a first lens group having a positive refractive power, a second lens group having a positive refractive power, and a negative refractive power. When focusing from an object at infinity to a nearby object, the first lens group to the third lens group are all moved toward the object side, and at this time, the first lens group The lens is configured to increase both the air distance between the second lens group and the air distance between the second lens group and the third lens group. As described above, the present invention corrects deterioration of spherical aberration, especially coma aberration, by increasing the air gap between the first lens group and the second lens group while extending them. The increase in distortion in the negative direction due to the extension of the lens group and the second lens group, and the balance of astigmatism are corrected by increasing the air gap between the second lens group and the third lens group. In other words, floating between the first and second lens groups mainly corrects spherical aberration and coma, while floating between the second and third lens groups mainly corrects distortion and astigmatism. By correcting aberrations, various aberrations can be corrected separately, making it possible to perform better correction. Further, in the present invention, a negative third lens having a predetermined refractive power is used.
By arranging the lens group closest to the image plane and increasing the air distance between the positive first lens group and the positive second lens group to focus on a nearby object, the first
The focusing movement amount of the lens group and the second lens group is made smaller. The present invention has the above basic configuration, and
It is characterized by satisfying the following conditions. (1) −14< 3 /<-3 (2) 0.1<m 3 /m 2 <0.8 However, is the focal length of the entire system, 3 is the focal length of the third lens group, and m 2 is the focal length of the second lens group. The amount of movement, m3 , is the amount of movement of the third lens group. Conditional expression (1) defines the refractive power of the third lens group, and together with conditional expression (2), it is related to the amount of movement of the first and second lens groups from infinity to close-up. . In other words, if the lower limit of conditional expression (1) is exceeded, the refractive power of the third lens group becomes too weak, and the amount of movement of the first and second lens groups from infinity to close-up (near the same magnification) becomes small. This would deviate from the purpose of the present invention, which is to realize the entire product in a compact mold. On the other hand, if the upper limit is exceeded, it becomes difficult to correct spherical aberration and astigmatism. Conditional expression (2) defines the movement amount ratio of the third lens group with respect to the first and second lens groups, and conditional expression (1)
At the same time, it is related to the amount of movement of the first and second lens groups from infinity to close-up, and at the same time relates to the correction of distortion aberration and astigmatism during close-up. In other words, if the upper limit of conditional expression (2) is exceeded, the above conditional expression
As in case (1), from infinity to the first position when approaching
It becomes impossible to reduce the amount of movement of the second lens group, and it becomes difficult to reduce fluctuations in distortion. On the other hand, if the lower limit of condition (2) is exceeded, it will become difficult to correct astigmatism under condition (1), and the effective diameter required for the third lens group will increase to achieve focusing close to the same magnification. Too much. Furthermore, under the above conditional expressions (1) and (2), the ratio of the amount of movement of the first lens group and the second lens group from infinity to close-up must be A reasonable value will be determined, but specifically, it is desirable to comply with the following conditional expression. (3) 1.14<m 1 /m 2 <1.22 where m 1 is the amount of movement of the first lens group. Conditional expression (3) is related to correction of spherical aberration and coma aberration from infinity to close range. That is, if the upper limit is exceeded, spherical aberration at close range will be insufficiently corrected, while if the lower limit is exceeded, it will be difficult to correct coma aberration while taking image surface properties into consideration. In carrying out the present invention, it is preferable that the following conditional expressions are further complied with. (4) 0.1<ΔdA/ΔdB<0.5 However, ΔdA the amount of change in the air gap between the first lens group and the second lens group, ΔdB the amount of change in the air gap between the second lens group and the third lens group
This is the amount of change in air spacing between lens groups. (5) 0.05<m 3 /m 1 <0.7 The above conditional expression (4) defines the increase ratio of the air distance between the first and second lens groups and the second and third lens groups, which both increase during focusing. If the upper limit value is exceeded, it becomes difficult to correct variations in spherical aberration and coma aberration during close focusing, while if the lower limit value is exceeded, it becomes difficult to correct variations in spherical aberration and specific point aberration in a well-balanced manner. . Furthermore, conditional expression (5) is also related to conditional expressions (1) and (2), and if the lower limit is exceeded, the effective diameter of the third group must be increased, and correction of field curvature fluctuations becomes impossible. It will be enough. On the other hand, if the upper limit of conditional expression (5) is exceeded, the effect of reducing the focusing extension amount of the first and second lens groups will be diminished, and it will become difficult to correct fluctuations in distortion. As a specific lens configuration of the present invention, the following is desirable. That is, the first lens group includes, in order from the object side, a positive lens, a positive meniscus lens with a convex surface facing the object side, and a negative lens,
The second lens group is a cemented lens made by bonding together a negative lens with a surface with a strong curvature facing the object side and a positive lens with a surface with a strong curvature facing the image side, and a cemented lens with the surface with a strong curvature facing the image side. It is composed of a positive lens, and the third lens group is composed of a negative meniscus lens with a convex surface facing the object side. Note that the negative meniscus lens constituting the third lens group in the above has weak refractive power and is less affected by changes in lens back due to temperature change, as is clear from conditional expression (2), so it should be constructed from a plastic lens. is possible. (See Embodiment 3) The specific shape of the third lens group, which is a meniscus lens with a weak refractive power, can be easily manufactured if it is made of oplastic. Next, the specifications of the infinity focus state in the embodiment of the present invention will be shown. In the example, ri is the radius of curvature of the i-th surface from the object side, di is the i-th axial distance from the object side, and Ni and νi are the refractive index of the i-th lens from the object side, respectively. This is Atsbe's number.
【表】【table】
【表】【table】
【表】【table】
【表】【table】
【表】【table】
第１図から第３図は本発明の実施例１から３の
各レンズ構成図、第４図から第６図は実施例１か
ら３のそれぞれの諸収差図を示す。
……第１レンズ群、……第２レンズ群、
……第３レンズ群。
1 to 3 show respective lens configuration diagrams of Examples 1 to 3 of the present invention, and FIGS. 4 to 6 show various aberration diagrams of Examples 1 to 3, respectively. ...first lens group, ...second lens group,
...Third lens group.
Claims (1)
ズ群、正の屈折力を有する第２レンズ群、そ
して負の屈折力を有する第３レンズ群の３群か
ら構成され、無限遠物体から近接物体へのフオー
カシングに際して、前記第１レンズ群と第２レン
ズ群間の空気間隔及び前記第２レンズ群と第３レ
ンズ群間の空気間隔がともに増大するよう前記第
１レンズ群から第３レンズ群をいずれも物体側に
移動させて合焦を行うとともに、以下の条件式を
満足することを特徴とする大口径マクロレンズ： −14＜3／＜−３ 0.1＜m3／m2＜0.8 但し：全系の焦点距離、3 ：第３レンズ群の焦点距離、 m2：第２レンズ群の移動量、 m3：第３レンズ群の移動量。 ２ さらに以下の条件を満足することを特徴とす
る特許請求の範囲第１項記載の大口径マクロレン
ズ： 0.1＜ΔdA／ΔdB＜0.5 但し、 ΔdA：第１レンズ群と第２レンズ群の間の空気
間隔の変化量、 ΔdB：第２レンズ群と第３レンズ群の間の空気
間隔の変化量。 ３ さらに以下の条件を満足することを特徴とす
る特許請求の範囲第１項記載の大口径マクロレン
ズ： 0.05＜m3／m1＜0.7 但し、m1：第１レンズ群の移動量。 ４ 物体側より順に前記第１レンズ群は、正レン
ズ、物体側に凸面を向けた正メニスカスレンズ及
び負レンズより成り、前記第２レンズ群は曲率の
強い面を物体側に向けた負レンズと曲率の強い面
を像側に向けた正レンズとを貼り合わせて成る接
合レンズ及び曲率の強い面を像側に向けた正レン
ズより成り、前記第３レンズ群は物体側に凸面を
向けた負のメニスカスレンズより成ることを特徴
とする特許請求の範囲第１項記載の大口径マクロ
レンズ。 ５ 前記第３レンズ群がプラスチツクレンズであ
ることを特徴とする特許請求の範囲第４項記載の
大口径マクロレンズ。 ６ さらに以下の条件を満足することを特徴とす
る特許請求の範囲第１項記載の大口径マクロレン
ズ： 1.14＜m1／m2＜1.22 m1：第１レンズ群の移動量。[Claims] 1 Consisting of three lens groups in order from the object side: a first lens group having a positive refractive power, a second lens group having a positive refractive power, and a third lens group having a negative refractive power. , when focusing from an object at infinity to a nearby object, the first lens is arranged so that both the air distance between the first lens group and the second lens group and the air distance between the second lens group and the third lens group increase. A large-diameter macro lens characterized by moving the third lens group from the group toward the object side for focusing, and satisfying the following conditional expressions: -14< 3 /<-3 0.1< m3 /m 2 <0.8 However: Focal length of the entire system, 3 : Focal length of the third lens group, m 2 : Amount of movement of the second lens group, m 3 : Amount of movement of the third lens group. 2. The large-diameter macro lens according to claim 1, which further satisfies the following conditions: 0.1<ΔdA/ΔdB<0.5, where ΔdA is the distance between the first lens group and the second lens group. Amount of change in air distance, ΔdB: Amount of change in air distance between the second lens group and the third lens group. 3. The large-diameter macro lens according to claim 1, which further satisfies the following conditions: 0.05<m 3 /m 1 <0.7 where m 1 is the amount of movement of the first lens group. 4. In order from the object side, the first lens group consists of a positive lens, a positive meniscus lens with a convex surface facing the object side, and a negative lens, and the second lens group includes a negative lens with a highly curved surface facing the object side. The third lens group consists of a cemented lens made by bonding together a positive lens with a surface with strong curvature facing the image side, and a positive lens with a surface with strong curvature facing the image side, and the third lens group is a negative lens with a convex surface facing the object side. A large-diameter macro lens according to claim 1, characterized in that the macro lens comprises a meniscus lens. 5. The large-diameter macro lens according to claim 4, wherein the third lens group is a plastic lens. 6. The large-diameter macro lens according to claim 1, further satisfying the following conditions: 1.14<m 1 /m 2 <1.22 m 1 : Amount of movement of the first lens group.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10335083A JPS59228220A (en) | 1983-06-08 | 1983-06-08 | Large diameter macro lens |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10335083A JPS59228220A (en) | 1983-06-08 | 1983-06-08 | Large diameter macro lens |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS59228220A JPS59228220A (en) | 1984-12-21 |
| JPH0441322B2 true JPH0441322B2 (en) | 1992-07-08 |
Family
ID=14351682
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP10335083A Granted JPS59228220A (en) | 1983-06-08 | 1983-06-08 | Large diameter macro lens |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS59228220A (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0685018B2 (en) * | 1986-02-24 | 1994-10-26 | オリンパス光学工業株式会社 | Macro lens |
| JPH0750243B2 (en) * | 1986-12-11 | 1995-05-31 | キヤノン株式会社 | Shooting lens with variable optical characteristics |
| JP2594450B2 (en) * | 1988-02-23 | 1997-03-26 | 旭光学工業株式会社 | Macro lens |
| JP2697119B2 (en) * | 1989-04-26 | 1998-01-14 | 株式会社ニコン | Lens system capable of short-range shooting |
| CN110346904B (en) * | 2019-06-29 | 2021-08-17 | 瑞声光学解决方案私人有限公司 | Image pickup optical lens |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS56107210A (en) * | 1980-01-31 | 1981-08-26 | Nippon Kogaku Kk <Nikon> | Lens system permitting short-distance photographing |
-
1983
- 1983-06-08 JP JP10335083A patent/JPS59228220A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS56107210A (en) * | 1980-01-31 | 1981-08-26 | Nippon Kogaku Kk <Nikon> | Lens system permitting short-distance photographing |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS59228220A (en) | 1984-12-21 |
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