JP3008715B2 - Zoom lens - Google Patents
Zoom lensInfo
- Publication number
- JP3008715B2 JP3008715B2 JP5029922A JP2992293A JP3008715B2 JP 3008715 B2 JP3008715 B2 JP 3008715B2 JP 5029922 A JP5029922 A JP 5029922A JP 2992293 A JP2992293 A JP 2992293A JP 3008715 B2 JP3008715 B2 JP 3008715B2
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- lens
- distance
- refractive power
- zoom lens
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Description
【０００１】[0001]
【産業上の利用分野】本発明はズームレンズに関し、特
に広角端の撮影画角が５８度程度、変倍比３程度の高変
倍比の全変倍範囲にわたり、また物体距離全般にわたり
高い光学性能を有した写真用カメラ（スチルカメラ）や
ビデオカメラ等に好適なズームレンズに関するものであ
る。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a zoom lens, and more particularly to a zoom lens having a high angle of view at a wide-angle end of about 58 degrees, a high zoom ratio of about 3 and a high optical power over the entire object distance. The present invention relates to a zoom lens suitable for a photographic camera (still camera), a video camera, and the like having high performance.
【０００２】[0002]
【従来の技術】最近のスチルカメラ、ビデオカメラ等の
ズームレンズには高変倍比のものが要求されている。一
般にズームレンズにおいて、高変倍化を図るには各レン
ズ群の屈折力を強めたり、レンズ移動量を増大させたり
しなければならず、一般にはこれに伴い前玉レンズ径が
増大し、レンズ全長も長くなり、レンズ系全体が大型化
してくる。2. Description of the Related Art Recently, zoom lenses such as still cameras and video cameras are required to have a high zoom ratio. In general, in a zoom lens, in order to achieve a high zoom ratio, it is necessary to increase the refractive power of each lens group or increase the amount of movement of the lens. In general, the diameter of the front lens increases with this. The overall length becomes longer, and the entire lens system becomes larger.
【０００３】これに対して、従来より写真用カメラやビ
デオカメラ等のズームレンズにおいては物体側の第１群
以外のレンズ群を移動させてフォーカスを行う、所謂リ
ヤーフォーカス式を採用したものが種々と提案されてい
る。On the other hand, various zoom lenses such as a photographic camera and a video camera which adopt a so-called rear focus system in which a lens group other than the first group on the object side is moved to perform focusing are conventionally used. It has been proposed.
【０００４】一般にリヤーフォーカス式のズームレンズ
は第１群を移動させてフォーカスを行うズームレンズに
比べて第１群の有効径が小さくなり、レンズ系全体の小
型化が容易になり、また近接撮影、特に極近接撮影が容
易となり、更に比較的小型軽量のレンズ群を移動させて
行っているので、レンズ群の駆動力が小さくてすみ迅速
な焦点合わせができる等の特徴がある。In general, a rear focus type zoom lens has a smaller effective diameter of the first lens group than a zoom lens which moves and focuses the first lens group, so that the entire lens system can be easily miniaturized, and close-up photographing can be performed. In particular, extremely close-up photography is facilitated, and the relatively small and lightweight lens group is moved, so that the driving force of the lens group is small and quick focusing can be performed.
【０００５】このようなリヤーフォーカス式のズームレ
ンズとして例えば特開平３−２４９６１４号公報では物
体側より順に正の屈折力の第１群、正又は負の屈折力の
第２群、正の屈折力の第３群、そして負の屈折力の第４
群の４つのレンズ群より成り、各レンズ群を移動させて
変倍を行うと共に第１群以外のレンズ群を移動させてフ
ォーカスを行ったズームレンズが提案されている。[0005] As such a rear focus type zoom lens, for example, in Japanese Patent Laid-Open No. 3-249614, a first lens unit having a positive refractive power, a second lens unit having a positive or negative refractive power, and a positive refractive power are described in order from the object side. The third group, and the fourth with negative refractive power
A zoom lens has been proposed, which includes four lens groups, and performs zooming by moving each lens group and focuses by moving lens groups other than the first group.
【０００６】[0006]
【発明が解決しようとする課題】一般にズームレンズに
おいてリヤーフォーカス方式を採用するとレンズ系全体
が小型化され、また迅速なるフォーカスが可能となる。Generally, when a rear focus system is employed in a zoom lens, the entire lens system is reduced in size, and quick focusing becomes possible.
【０００７】しかしながら反面、フォーカスの際の収差
変動が大きくなり、無限遠物体から近距離物体に至る物
体距離全般にわたりレンズ系全体の小型化を図りつつ高
い光学性能を得るのが大変難しくなってくるという問題
点が生じてくる。特に高変倍のズームレンズでは全変倍
範囲にわたり、また物体距離全般にわたり高い光学性能
を得るのが大変難しくなってくるという問題点が生じて
くる。On the other hand, however, aberration fluctuations during focusing increase, and it becomes very difficult to obtain high optical performance while reducing the size of the entire lens system over the entire object distance from an object at infinity to an object at a short distance. The problem arises. In particular, a high-magnification zoom lens has a problem that it becomes very difficult to obtain high optical performance over the entire magnification range and over the entire object distance.
【０００８】本発明は第１群以外のレンズ群でフォーカ
スを行うリヤーフォーカス方式を採用しつつ、高変倍化
を図ると共にレンズ系全体の小型化を図りつつ、広角端
から望遠端に至る全変倍範囲にわたり、また無限遠物体
から近距離物体に至る物体距離全般にわたり、良好なる
光学性能を有したズームレンズの提供を目的とする。The present invention employs a rear focus method in which focusing is performed by a lens group other than the first lens group, and achieves a high zoom ratio and reduces the size of the entire lens system. It is an object of the present invention to provide a zoom lens having excellent optical performance over a variable power range and over an entire object distance from an object at infinity to an object at a short distance.
【０００９】[0009]
【課題を解決するための手段】請求項１の発明のズーム
レンズは、物体側より順に、正の屈折力の第１群、正又
は負の屈折力の第２群、正の屈折力の第３群、そして負
の屈折力の第４群の４つのレンズ群を有し、該第１群と
第２群の間隔が増大し、該第２群と第３群の間隔が変化
し、該第３群と第４群の間隔が減少するように、所定の
レンズ群を移動させて広角端から望遠端への変倍を行う
と共に、該第２群と第３群を物体側へ移動させて無限遠
物体から近距離物体へのフォーカスを行うズームレンズ
であって、該第２群を物体側に凹面を向けた負レンズ
と、１つ又は２つの正レンズより構成し、該第３群を２
つの正レンズと１つの負レンズの３つのレンズ又は１つ
の負レンズと１つの正レンズの２つのレンズより構成
し、該第２群中の少なくとも１枚のレンズを絞りよりも
像面側に配置し、望遠側の全系の焦点距離をｆＴ、第１
群の焦点距離をｆ１、第２群及び第３群の望遠端の合成
焦点距離をｆ２，３としたとき、 ０．４５＜ｆ１／ｆＴ＜１．３５ ‥‥‥（１） ０．２＜ｆ２，３／ｆＴ＜０．４５ ‥‥‥（２） なる条件式を満足することを特徴としている。特に、 （イ）前記絞りはフォーカスの際に固定であること （ロ）前記第２群と第３群とを一体的に移動させてフォ
ーカスを行っていること （ハ）前記第２群又は第３群と前記絞りは変倍の際に一
体的に移動していること （ニ）広角端から望遠端への変倍に際して前記第１群〜
第４群を全て物体側へ移動していること （ホ）前記絞りは前記第２群の前方に配置していること 等を特徴としている。According to a first aspect of the present invention, there is provided a zoom lens having a first lens unit having a positive refractive power, a second lens unit having a positive or negative refractive power, and a positive lens having a positive refractive power. The zoom lens has four lens groups, three groups and a fourth group having a negative refractive power. The distance between the first group and the second group increases, the distance between the second group and the third group changes, By moving a predetermined lens unit to change the magnification from the wide-angle end to the telephoto end so that the distance between the third unit and the fourth unit is reduced, the second unit and the third unit are moved toward the object side. A second lens group comprising a negative lens having a concave surface facing the object side and one or two positive lenses; 2
Consisting of three lenses, one positive lens and one negative lens, or two lenses, one negative lens and one positive lens, and at least one lens in the second group is located closer to the image plane than the stop. The focal length of the entire system on the telephoto side is fT,
When the focal length of the group is f1 and the combined focal length of the second group and the third group at the telephoto end is f2, 3, 0.45 <f1 / fT <1.35 (1) 0.2 < f2, 3 / fT <0.45 (2) The condition is satisfied. In particular, (a) the aperture is fixed during focusing. (B) the second and third units are integrally moved for focusing. (C) the second or third unit is focused. The third lens group and the aperture stop move together during zooming.
(E) the diaphragm is disposed in front of the second group, and the like.
【００１０】請求項７の発明のズームレンズは、物体側
より順に、正の屈折力の第１群、絞り、正又は負の屈折
力の第２群、正の屈折力の第３群、そして負の屈折力の
第４群の４つのレンズ群を有し、該第１群と第２群の間
隔が増大し、該第２群と第３群の間隔が減少し、該第３
群と第４群の間隔が減少するように、所定のレンズ群を
移動させて広角端から望遠端への変倍を行うと共に、該
第２群と第３群を物体側へ移動させて無限遠物体から近
距離物体へのフォーカスを行うズームレンズであって、
該絞りは、変倍の際に該第３群と一体的に移動すると共
に、フォーカスの際に固定であることを特徴としてい
る。特に、望遠側の全系の焦点距離をｆＴ、第１群の焦
点距離をｆ１、第２群及び第３群の望遠端の合成焦点距
離をｆ２，３としたとき、 ０．４５＜ｆ１／ｆＴ＜１．３５ ‥‥‥（１） ０．２＜ｆ２，３／ｆＴ＜０．４５ ‥‥‥（２） なる条件式を満足することを特徴としている。According to a seventh aspect of the present invention, there is provided a zoom lens having, in order from the object side, a first lens unit having a positive refractive power, a stop, a second lens unit having a positive or negative refractive power, a third lens unit having a positive refractive power, and The fourth lens unit includes a fourth lens unit having a negative refractive power. The distance between the first and second units increases, the distance between the second and third units decreases, and the third lens unit decreases.
A predetermined lens group is moved to change the magnification from the wide-angle end to the telephoto end so that the distance between the group and the fourth group is reduced, and the second and third groups are moved to the object side to infinity. A zoom lens for focusing from a distant object to a close object,
The diaphragm is characterized in that it moves integrally with the third lens unit during zooming and is fixed during focusing. In particular, when the focal length of the entire system on the telephoto side is fT, the focal length of the first unit is f1, and the combined focal length of the telephoto end of the second and third units is f2, 3, 0.45 <f1 / fT <1.35 ‥‥‥ (1) 0.2 <f2,3 / fT <0.45 ‥‥‥ (2)
【００１１】[0011]
【実施例】図１は本発明の数値実施例１のレンズ断面
図、図２，図３は本発明の数値実施例２，３の広角端の
レンズ断面図である。図４，図５は本発明の数値実施例
１の広角端と望遠端の収差図、図６，図７は本発明の数
値実施例２の広角端と望遠端の収差図、図８，図９は本
発明の数値実施例３の広角端と望遠端の収差図である。
収差図において（Ａ）は無限遠物体、（Ｂ）は物体距離
８００（ｍｍ）のときを示している。FIG. 1 is a sectional view of a lens of Numerical Embodiment 1 of the present invention, and FIGS. 2 and 3 are sectional views of lenses at the wide angle end of Numerical Embodiments 2 and 3 of the present invention. 4 and 5 are aberration diagrams at the wide angle end and the telephoto end of Numerical Embodiment 1 of the present invention, and FIGS. 6 and 7 are aberration diagrams at the wide angle end and the telephoto end of Numerical Embodiment 2 of the present invention. 9 is an aberration diagram at a wide-angle end and a telephoto end in Numerical Example 3 of the present invention.
In the aberration diagrams, (A) shows an object at infinity, and (B) shows an object distance of 800 (mm).
【００１２】図中、Ｌ１は正の屈折力の第１群、Ｌ２は
正又は負の屈折力の第２群、Ｌ３は正の屈折力の第３
群、Ｌ４は負の屈折力の第４群である。ＳＰは絞りであ
り、第２群の前方（物体側）に配置している。Ｆは像面
である。In the drawing, L1 is a first group having a positive refractive power, L2 is a second group having a positive or negative refractive power, and L3 is a third group having a positive refractive power.
The group L4 is a fourth group having a negative refractive power. SP denotes an aperture, which is arranged in front of the second group (object side). F is an image plane.
【００１３】広角端から望遠端への変倍に際しては矢印
のように各レンズ群を物体側へ移動させることにより行
っている。このとき広角端に比べて望遠端で第１群と第
２群との間隔が増大し、第２群と第３群との間隔が縮小
し、第３群と第４群との間隔が縮小するようにしてい
る。変倍の際には、絞りＳＰを第２群又は第３群と一体
的に移動させている。これにより変倍の際の移動要素構
造の簡素化を図っている。The zooming from the wide-angle end to the telephoto end is performed by moving each lens unit to the object side as shown by the arrow. At this time, the distance between the first and second units increases at the telephoto end compared to the wide-angle end, the distance between the second and third units decreases, and the distance between the third and fourth units decreases. I am trying to do it. During zooming, the stop SP is moved integrally with the second or third lens unit. This simplifies the moving element structure during zooming.
【００１４】特に広角端から望遠端への変倍に際して、
第２群と第３群との間隔が小さくなるようにし、かつ絞
りＳＰと第３群とを一体的に物体側へ移動させることに
より、望遠側においてフォーカス用のレンズ群（第２群
と第３群）の移動空間を確保している。即ち広角端に比
べ望遠側において多く必要とするフォーカス用のレンズ
群の移動空間を効果的に確保している。In particular, when zooming from the wide-angle end to the telephoto end,
By reducing the distance between the second and third units and moving the stop SP and the third unit integrally to the object side, a focusing lens unit (the second and third units) is set on the telephoto side. Group 3) is secured. That is, the moving space of the focusing lens group, which is required more on the telephoto side than at the wide-angle end, is effectively secured.
【００１５】本実施例では第２群の少なくとも１つのレ
ンズが絞りＳＰよりも像面側に位置するようにしてい
る。図１では第２群の全てのレンズが絞りＳＰよりも像
面側に位置するようにしている。これにより絞りＳＰが
第２群からみると物体側に位置するようにして、入射瞳
が前玉レンズ群近傍に位置するようにして前玉レンズ径
の小型化を図っている。In this embodiment, at least one lens of the second group is located closer to the image plane than the stop SP. In FIG. 1, all the lenses of the second group are positioned closer to the image plane than the stop SP. Thus, the aperture SP is positioned on the object side when viewed from the second group, and the entrance pupil is positioned near the front lens group, thereby reducing the diameter of the front lens.
【００１６】本実施例では無限遠物体から近距離物体へ
のフォーカスを第２群と第３群とを一体的に物体側へ移
動させて行う、リヤーフォーカス式を採用している。こ
れにより本実施例では従来の４群ズームレンズにおい
て、第１群を繰り出してフォーカスを行う場合に比べ
て、このようなリヤーフォーカス方式を採ることにより
第１群のレンズ有効径の増大化を効果的に防止してい
る。In this embodiment, a rear focus system is used in which focusing from an object at infinity to an object at a short distance is performed by moving the second and third units together toward the object side. As a result, in the present embodiment, by adopting such a rear focus method as compared with a conventional four-unit zoom lens in which the first unit is extended and focused, the effective lens diameter of the first unit is increased. Prevention.
【００１７】またフォーカスの際の移動要素を１つとし
てフォーカス駆動構造の簡素化及び小型化を図ってい
る。絞り構造はレンズ鏡筒構造の中でも比較的大きな部
品構造となるために、本実施例では絞りＳＰはフォーカ
スの際に固定としている。これによりレンズ鏡筒構造の
簡素化を図っている。Further, the focus driving structure is simplified and downsized by using only one moving element at the time of focusing. In this embodiment, the aperture SP is fixed at the time of focusing because the aperture structure has a relatively large component structure among the lens barrel structures. This simplifies the lens barrel structure.
【００１８】尚本発明において、更に望ましくは次の条
件式を満足するのが良い。In the present invention, it is more desirable to satisfy the following conditional expression.
【００１９】望遠側の全系の焦点距離をｆＴ 第１群の焦点距離をｆ１ 第２，３群の望遠端の合成焦点距離をｆ２，３としたと
き ０．４５＜ｆ１／ｆＴ＜１．３５ ・・・・・（１） ０．２＜ｆ２，３／ｆＴ＜０．４５ ・・・・（２）と
することである。When the focal length of the entire system on the telephoto side is fT, the focal length of the first lens unit is f1, and when the composite focal length of the second and third lens units at the telephoto end is f2,3, 0.45 <f1 / fT <1. 35 (1) 0.2 <f2, 3 / fT <0.45 (2)
【００２０】上記２つの条件式は、フォーカス用のレン
ズ群の繰り出し量を適切に設定する為の式である。条件
式（１）の上限値を越えると第２，３群の合成倍率が小
さくなりすぎるためフォーカス用のレンズ群の繰り出し
量が大きくなり、結果としてカメラ全体が大型化するの
で良くない。又下限値を越えると、第２群へ入射する光
束が強く収れんしてしまうため、フォーカス時に特に球
面収差とコマ収差の変動が著しくなるので良くない。The above two conditional expressions are expressions for appropriately setting the amount of extension of the focusing lens group. When the value exceeds the upper limit of conditional expression (1), the combined magnification of the second and third lens units becomes too small, so that the amount of extension of the focusing lens unit becomes large. As a result, the entire camera becomes large, which is not good. On the other hand, if the lower limit value is exceeded, the light beam incident on the second lens unit is strongly converged, and the fluctuation of spherical aberration and coma in particular during focusing becomes remarkable, which is not good.
【００２１】条件式（２）の上限値を越えると、フォー
カス用のレンズ群の繰り出し量が多くなり、結果として
カメラ全体が大型化するので良くない。又下限値を越え
ると、フォーカスによる収差変動を補正するためにレン
ズ枚数が多く必要とし、結果としてカメラ全体が大型化
するので良くない。When the value exceeds the upper limit of conditional expression (2), the amount of extension of the focusing lens unit increases, and as a result, the entire camera becomes large, which is not good. On the other hand, if the lower limit value is exceeded, a large number of lenses will be required to correct aberration fluctuations due to focusing, and as a result the entire camera will be large, which is not good.
【００２２】本発明において変倍比３，Ｆナンバー３．
５程度を確保しつつ、全変倍範囲にわたり、また物体距
離全般にわたり高い光学性能を得るためには各レンズ群
を次の如く構成するのが良い。In the present invention, the zoom ratio is 3 and the F number is 3.
In order to obtain high optical performance over the entire zoom range and over the entire object distance while securing about 5, it is preferable to configure each lens group as follows.
【００２３】第１群を物体側に凸面を向けたメニスカス
状の負レンズ、物体側に凸面を向けたメニスカス状の正
のレンズの独立又は貼合わせレンズより構成し、第２群
を物体側に凹面を向けた負レンズ、１つ又は２つの正レ
ンズより構成し、第３群を２つの正レンズと１つの負レ
ンズの３つのレンズ又は１つの負レンズと１つの正レン
ズの２つのレンズより構成し、第４群を像面側に凸面を
向けたメニスカス状の正レンズ、負レンズ、像面側に凸
面を向けたメニスカス状の負レンズの３つのレンズより
構成するのが良い。The first group comprises an independent or laminated meniscus negative lens having a convex surface facing the object side and a meniscus positive lens having a convex surface facing the object side. The third group is composed of two lenses of two positive lenses and one negative lens, or two lenses of one negative lens and one positive lens. It is preferable that the fourth lens unit includes three lenses: a positive meniscus lens having a convex surface facing the image surface, a negative lens, and a negative meniscus lens having a convex surface facing the image surface.
【００２４】次に本発明の数値実施例を示す。数値実施
例においてＲｉは物体側より順に第ｉ番目のレンズ面の
曲率半径、Ｄｉは物体側より第ｉ番目のレンズ厚及び空
気間隔、Ｎｉとνｉは各々物体側より順に第ｉ番目のレ
ンズのガラスの屈折率とアッベ数である。Next, numerical examples of the present invention will be described. In the numerical examples, Ri is the radius of curvature of the i-th lens surface in order from the object side, Di is the i-th lens thickness and air spacing from the object side, and Ni and νi are the i-th lens surfaces in order from the object side. The refractive index and Abbe number of glass.
【００２５】非球面形状は光軸方向にＸ軸、光軸と垂直
方向にＨ軸、光の進行方向を正としＲを近軸曲率半径、
Ｂ，Ｃ，Ｄ，Ｅを各々非球面係数としたときThe aspherical surface has an X-axis in the optical axis direction, an H-axis in a direction perpendicular to the optical axis, a positive traveling direction of light, R is a paraxial radius of curvature,
When B, C, D and E are each aspheric coefficients
【００２６】[0026]
【数１】 なる式で表わしている。 （数値実施例１） F= 39.0 FNO=1:3.5〜 8.2 2 ω= 58°〜 23.6° R 1= 98.66 D 1= 1.50 N 1=1.84666 ν 1= 23.9 R 2= 57.57 D 2= 1.00 R 3= 22.81 D 3= 2.00 N 2=1.48749 ν 2= 70.2 R 4= 90.45 D 4= 可変 R 5= (絞り) D 5= 0.00 R 6= -13.55 D 6= 1.00 N 3=1.51633 ν 3= 64.2 R 7= 10.22 D 7= 4.52 N 4=1.58267 ν 4= 46.4 R 8= -19.87 D 8= 可変 R 9= -80.16 D 9= 1.50 N 5=1.51633 ν 5= 64.2 R10= -37.21 D10= 0.12 R11= 55.02 D11= 4.40 N 6=1.51633 ν 6= 64.2 R12= -10.11 D12= 1.10 N 7=1.84666 ν 7= 23.9 R13= -19.58 D13= 可変 R14= -45.42 D14= 3.00 N 8=1.84666 ν 8= 23.8 R15= -19.03 D15= 0.12 R16= -26.61 D16= 1.20 N 9=1.69680 ν 9= 55.5 R17= 181.75 D17= 5.50 R18= -14.54 D18= 1.50 N10=1.71300 ν10= 53.8 R19= -55.95 (Equation 1) It is represented by the following equation. (Numerical Example 1) F = 39.0 FNO = 1: 3.5 to 8.2 2 ω = 58 ° to 23.6 ° R 1 = 98.66 D 1 = 1.50 N 1 = 1.84666 ν 1 = 23.9 R 2 = 57.57 D 2 = 1.00 R 3 = 22.81 D 3 = 2.00 N 2 = 1.48749 ν 2 = 70.2 R 4 = 90.45 D 4 = Variable R 5 = (Aperture) D 5 = 0.00 R 6 = -13.55 D 6 = 1.00 N 3 = 1.51633 ν 3 = 64.2 R 7 = 10.22 D 7 = 4.52 N 4 = 1.58267 ν 4 = 46.4 R 8 = -19.87 D 8 = Variable R 9 = -80.16 D 9 = 1.50 N 5 = 1.51633 ν 5 = 64.2 R10 = -37.21 D10 = 0.12 R11 = 55.02 D11 = 4.40 N 6 = 1.51633 ν 6 = 64.2 R12 = -10.11 D12 = 1.10 N 7 = 1.84666 ν 7 = 23.9 R13 = -19.58 D13 = Variable R14 = -45.42 D14 = 3.00 N 8 = 1.84666 ν 8 = 23.8 R15 = -19.03 D15 = 0.12 R16 = -26.61 D16 = 1.20 N 9 = 1.69680 ν 9 = 55.5 R17 = 181.75 D17 = 5.50 R18 = -14.54 D18 = 1.50 N10 = 1.71300 ν10 = 53.8 R19 = -55.95
【００２７】[0027]
【表１】 （数値実施例２） F= 39.07 FNO=1:3.5〜 8.2 2 ω= 58°〜 23.6° R 1= 27.24 D 1= 1.30 N 1=1.84666 ν 1= 23.8 R 2= 22.42 D 2= 2.80 N 2=1.48749 ν 2= 70.2 R 3= 263.66 D 3= 可変 R 4= (絞り) D 4= 2.75 R 5= -15.71 D 5= 0.80 N 3=1.74320 ν 3= 49.3 R 6= 17.56 D 6= 2.20 N 4=1.48749 ν 4= 70.2 R 7= -38.95 D 7= 1.26 R 8= 93.44 D 8= 2.36 N 5=1.84666 ν 5= 23.8 R 9= -25.24 D 9= 可変 R10= 188.68 D10= 1.10 N 6=1.84666 ν 6= 23.8 R11= 14.87 D11= 4.50 N 7=1.71300 ν 7= 53.8 R12= -24.97 D12= 可変 R13= -32.62 D13= 2.80 N 8=1.84666 ν 8= 23.8 R14= -19.22 D14= 0.15 R15= -26.53 D15= 1.40 N 9=1.69350 ν 9= 53.2 R16= 226.61 D16= 5.56 R17= -16.01 D17= 1.70 N10=1.74320 ν10= 49.3 R18= -41.29 [Table 1] (Numerical Example 2) F = 39.07 FNO = 1: 3.5 to 8.2 2 ω = 58 ° to 23.6 ° R 1 = 27.24 D 1 = 1.30 N 1 = 1.84666 ν 1 = 23.8 R 2 = 22.42 D 2 = 2.80 N 2 = 1.48749 ν 2 = 70.2 R 3 = 263.66 D 3 = Variable R 4 = (Aperture) D 4 = 2.75 R 5 = -15.71 D 5 = 0.80 N 3 = 1.74320 ν 3 = 49.3 R 6 = 17.56 D 6 = 2.20 N 4 = 1.48749 ν 4 = 70.2 R 7 = -38.95 D 7 = 1.26 R 8 = 93.44 D 8 = 2.36 N 5 = 1.84666 ν 5 = 23.8 R 9 = -25.24 D 9 = Variable R10 = 188.68 D10 = 1.10 N 6 = 1.84666 ν 6 = 23.8 R11 = 14.87 D11 = 4.50 N 7 = 1.71300 ν 7 = 53.8 R12 = -24.97 D12 = Variable R13 = -32.62 D13 = 2.80 N 8 = 1.84666 ν 8 = 23.8 R14 = -19.22 D14 = 0.15 R15 = -26.53 D15 = 1.40 N 9 = 1.69350 ν 9 = 53.2 R16 = 226.61 D16 = 5.56 R17 = -16.01 D17 = 1.70 N10 = 1.74320 ν10 = 49.3 R18 = -41.29
【００２８】[0028]
【表２】 （数値実施例３） F= 39.44 FNO=1:3.5〜 8.2 2 ω= 58°〜 23.6° R 1= 31.42 D 1= 1.40 N 1=1.84666 ν 1= 23.8 R 2= 25.59 D 2= 0.70 R 3= 22.50 D 3= 2.40 N 2=1.48749 ν 2= 70.2 R 4= 98.17 D 4= 可変 R 5= (絞り) D 5= 可変 R 6= -12.34 D 6= 2.80 N 3=1.51742 ν 3= 52.4 R 7= -43.74 D 7= 3.35 N 4=1.72825 ν 4= 28.5 R 8= -17.42 D 8= 可変 R 9= 31.99 D 9= 1.10 N 5=1.84666 ν 5= 23.8 R10= 14.81 D10= 4.00 N 6=1.58313 ν 6= 59.4 R11= -38.58 D11= 可変 R12= -28.32 D12= 2.50 N 7=1.84666 ν 7= 23.8 R13= -19.53 D13= 0.15 R14= -29.98 D14= 1.40 N 8=1.71300 ν 8= 53.8 R15=-121.19 D15= 4.09 R16= -20.81 D16= 1.70 N 9=1.74320 ν 9= 49.3 R17=-134.92 [Table 2] (Numerical Example 3) F = 39.44 FNO = 1: 3.5 to 8.2 2 ω = 58 ° to 23.6 ° R 1 = 31.42 D 1 = 1.40 N 1 = 1.84666 ν 1 = 23.8 R 2 = 25.59 D 2 = 0.70 R 3 = 22.50 D 3 = 2.40 N 2 = 1.48749 ν 2 = 70.2 R 4 = 98.17 D 4 = Variable R 5 = (Aperture) D 5 = Variable R 6 = -12.34 D 6 = 2.80 N 3 = 1.51742 ν 3 = 52.4 R 7 = -43.74 D 7 = 3.35 N 4 = 1.72825 ν 4 = 28.5 R 8 = -17.42 D 8 = Variable R 9 = 31.99 D 9 = 1.10 N 5 = 1.84666 ν 5 = 23.8 R10 = 14.81 D10 = 4.00 N 6 = 1.58313 ν 6 = 59.4 R11 = -38.58 D11 = Variable R12 = -28.32 D12 = 2.50 N 7 = 1.84666 ν 7 = 23.8 R13 = -19.53 D13 = 0.15 R14 = -29.98 D14 = 1.40 N 8 = 1.71300 ν 8 = 53.8 R15 = -121.19 D15 = 4.09 R16 = -20.81 D16 = 1.70 N 9 = 1.74320 ν 9 = 49.3 R17 = -134.92
【００２９】[0029]
【表３】 R11面 非球面 Ｋ＝−７．５９×１０-1，Ｂ＝８．４×１０-7，Ｃ＝
７．９５×１０-8 Ｄ＝−２．２９×１０-9，Ｅ＝１．２３×１０-11 [Table 3] R11 surface Aspherical surface K = −7.59 × 10 −1 , B = 8.4 × 10 −7 , C =
7.95 × 10 −8 D = −2.29 × 10 −9 , E = 1.23 × 10 −11
【００３０】[0030]
【発明の効果】本発明によれば以上のように各要素を設
定することにより、特に第１群以外のレンズ群でフォー
カスを行うリヤーフォーカス方式を採用することによ
り、高変倍化を図ると共にレンズ系全体の小型化を図り
つつ、広角端から望遠端に至る全変倍範囲にわたり、ま
た無限遠物体から近距離物体に至る物体距離全般にわた
り、良好なる光学性能を有したズームレンズを達成して
いる。According to the present invention, by setting each element as described above, especially by adopting a rear focus method in which focusing is performed by a lens group other than the first group, a high zoom ratio can be achieved. Achieved a zoom lens with excellent optical performance over the entire zoom range from the wide-angle end to the telephoto end, and over the entire object distance from infinity to close-range objects, while miniaturizing the entire lens system. ing.
【図１】 本発明の数値実施例１のレンズ断面図FIG. 1 is a sectional view of a lens according to a numerical example 1 of the present invention.
【図２】 本発明の数値実施例２のレンズ断面図FIG. 2 is a sectional view of a lens according to a numerical example 2 of the present invention.
【図３】 本発明の数値実施例３のレンズ断面図FIG. 3 is a sectional view of a lens according to a numerical example 3 of the present invention.
【図４】 本発明の数値実施例１の広角端の収差図FIG. 4 is an aberration diagram at a wide-angle end according to Numerical Embodiment 1 of the present invention.
【図５】 本発明の数値実施例１の望遠端の収差図FIG. 5 is an aberration diagram at a telephoto end in Numerical Example 1 of the present invention;
【図６】 本発明の数値実施例２の広角端の収差図FIG. 6 is an aberration diagram at a wide angle end according to Numerical Example 2 of the present invention.
【図７】 本発明の数値実施例２の望遠端の収差図FIG. 7 is an aberration diagram at a telephoto end in Numerical Example 2 of the present invention;
【図８】 本発明の数値実施例３の広角端の収差図FIG. 8 is an aberration diagram at a wide angle end according to Numerical Example 3 of the present invention.
【図９】 本発明の数値実施例３の望遠端の収差図FIG. 9 is an aberration diagram at a telephoto end in Numerical Example 3 of the present invention.
Ｌ１ 第１群 Ｌ２ 第２群 Ｌ３ 第３群 Ｌ４ 第４群 ＳＰ 絞り Ｆ 像面 L1 First group L2 Second group L3 Third group L4 Fourth group SP Aperture F Image plane
───────────────────────────────────────────────────── フロントページの続き (72)発明者 西尾 彰宏 東京都大田区下丸子３丁目30番２号 キ ヤノン株式会社内 (72)発明者 小山 剛史 東京都大田区下丸子３丁目30番２号 キ ヤノン株式会社内 (56)参考文献 特開 平３−249614（ＪＰ，Ａ) 特開 昭60−142319（ＪＰ，Ａ) (58)調査した分野(Int.Cl.7，ＤＢ名) G02B 9/00 - 17/08 G02B 21/02 - 21/04 G02B 25/00 - 25/04 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Akihiro Nishio 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Takeshi Koyama 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon (56) References JP-A-3-249614 (JP, A) JP-A-60-142319 (JP, A) (58) Fields investigated (Int. Cl. 7 , DB name) G02B 9/00 -17/08 G02B 21/02-21/04 G02B 25/00-25/04
Claims (8)
正又は負の屈折力の第２群、正の屈折力の第３群、そし
て負の屈折力の第４群の４つのレンズ群を有し、該第１
群と第２群の間隔が増大し、該第２群と第３群の間隔が
変化し、該第３群と第４群の間隔が減少するように、所
定のレンズ群を移動させて広角端から望遠端への変倍を
行うと共に、該第２群と第３群を物体側へ移動させて無
限遠物体から近距離物体へのフォーカスを行うズームレ
ンズであって、該第２群を物体側に凹面を向けた負レン
ズと、１つ又は２つの正レンズより構成し、該第３群を
２つの正レンズと１つの負レンズの３つのレンズ又は１
つの負レンズと１つの正レンズの２つのレンズより構成
し、該第２群中の少なくとも１枚のレンズを絞りよりも
像面側に配置し、望遠側の全系の焦点距離をｆＴ、第１
群の焦点距離をｆ１、第２群及び第３群の望遠端の合成
焦点距離をｆ２，３としたとき、 ０．４５＜ｆ１／ｆＴ＜１．３５ ０．２＜ｆ２，３／ｆＴ＜０．４５ なる条件式を満足する ことを特徴とするズームレンズ。1. A first group having a positive refractive power , in order from the object side,
The first lens group includes four lens groups, a second group having a positive or negative refractive power, a third group having a positive refractive power , and a fourth group having a negative refractive power .
The distance between the group and the second group increases, and the distance between the second group and the third group increases.
Change so that the distance between the third group and the fourth group decreases.
Move the fixed lens group to change the magnification from the wide-angle end to the telephoto end.
And moving the second and third units toward the object side to
A zoom lens that focuses from a telephoto object to a short-distance object
A negative lens having the second lens group with the concave surface facing the object side.
Lens, and one or two positive lenses.
Three lenses or two, one positive lens and one negative lens
Consists of two negative lenses and one positive lens
And, of the stop at least one lens in the second group are arranged on the image plane side, fT is a focal length of the entire system at the telephoto side, the first
The focal length of the group is f1, and the combination of the telephoto end of the second and third groups is
A zoom lens characterized by satisfying a conditional expression of 0.45 <f1 / fT <1.35 and 0.2 <f2,3 / fT <0.45 when a focal length is f2,3 .
ことを特徴とする請求項１のズームレンズ。2. The zoom lens according to claim 1, wherein the aperture is fixed during focusing.
せてフォーカスを行っていることを特徴とする請求項１
のズームレンズ。3. The focus is performed by moving the second group and the third group integrally.
Zoom lens.
の際に一体的に移動していることを特徴とする請求項１
のズームレンズ。4. The zoom lens system according to claim 1, wherein the second or third lens unit and the stop move integrally during zooming.
Zoom lens.
第１群〜第４群を全て物体側へ移動していることを特徴
とする請求項１のズームレンズ。5. The zoom lens according to claim 1, wherein all of the first to fourth units are moved to the object side during zooming from the wide-angle end to the telephoto end.
いることを特徴とする請求項１のズームレンズ。6. The zoom lens according to claim 1, wherein the stop is disposed in front of the second group.
絞り、正又は負の屈折力の第２群、正の屈折力の第３
群、そして負の屈折力の第４群の４つのレンズ群を有
し、該第１群と第２群の間隔が増大し、該第２群と第３
群の間隔が減少し、該第３群と第４群の間隔が減少する
ように、所定のレンズ群を移動させて広角 端から望遠端
への変倍を行うと共に、該第２群と第３群を物体側へ移
動させて無限遠物体から近距離物体へのフォーカスを行
うズームレンズであって、該絞りは、変倍の際に該第３
群と一体的に移動すると共に、フォーカスの際に固定で
あることを特徴とするズームレンズ。 7. A first group having a positive refractive power, in order from the object side,
Aperture, second group of positive or negative refractive power, third group of positive refractive power
Group, and 4 lens groups, 4th group with negative refractive power
The distance between the first group and the second group is increased, and the distance between the second group and the third group is increased.
The distance between the groups decreases, and the distance between the third and fourth groups decreases.
Move the specified lens group from the wide-angle end to the telephoto end.
And the second and third units are moved to the object side.
To focus from an object at infinity to a close object.
A zoom lens, wherein the aperture is set to the third position during zooming.
It moves together with the group and is fixed during focus.
A zoom lens characterized in that:
の焦点距離をｆ１、第２群及び第３群の望遠端の合成焦
点距離をｆ２，３としたとき、 ０．４５＜ｆ１／ｆＴ＜１．３５ ０．２＜ｆ２，３／ｆＴ＜０．４５ なる条件式を満足することを特徴とする請求項７のズー
ムレンズ。 8. The focal length of the entire system on the telephoto side is fT, the first group
Is the focal length of f1, and the composite focus of the second and third groups at the telephoto end is
8. The zoom according to claim 7, wherein a conditional expression of 0.45 <f1 / fT <1.35 0.2 <f2,3 / fT <0.45 is satisfied when the point distance is f2,3.
Murrens.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5029922A JP3008715B2 (en) | 1993-01-25 | 1993-01-25 | Zoom lens |
| US08/799,403 US5815320A (en) | 1993-01-14 | 1997-02-12 | Zoom lens |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5029922A JP3008715B2 (en) | 1993-01-25 | 1993-01-25 | Zoom lens |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH06222267A JPH06222267A (en) | 1994-08-12 |
| JP3008715B2 true JP3008715B2 (en) | 2000-02-14 |
Family
ID=12289490
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP5029922A Expired - Fee Related JP3008715B2 (en) | 1993-01-14 | 1993-01-25 | Zoom lens |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3008715B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008250136A (en) | 2007-03-30 | 2008-10-16 | Fujinon Corp | Imaging lens and imaging apparatus |
| JP5315755B2 (en) * | 2008-03-31 | 2013-10-16 | 株式会社ニコン | Optical system, optical system focusing method, and imaging apparatus having these |
-
1993
- 1993-01-25 JP JP5029922A patent/JP3008715B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH06222267A (en) | 1994-08-12 |
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