JP5726350B2 - Zoom lens and imaging apparatus having the same - Google Patents
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本発明はズームレンズ及びそれを有する撮像装置に関し、例えばビデオカメラや電子スチルカメラ、放送用カメラ、監視カメラ等のように固体撮像素子を用いた撮像装置、或いは銀塩フィルムを用いたカメラ等の撮像装置に好適なものである。 The present invention relates to a zoom lens and an image pickup apparatus having the same, such as an image pickup apparatus using a solid-state image pickup device such as a video camera, an electronic still camera, a broadcast camera, a surveillance camera, or a camera using a silver salt film. It is suitable for an imaging device.
近年、固体撮像素子を用いたビデオカメラ、デジタルスチルカメラ、放送用カメラ、監視カメラ、そして銀塩フィルムを用いたカメラ等の撮像装置は装置全体が小型化されている。そしてそれに用いる撮影光学系としてレンズ全長が短く、コンパクト（小型）で、高ズーム比（高変倍比）で、しかも高解像力のズームレンズであることが要求されている。これらの要求に応えるズームレンズとして、物体側より像側へ順に、正、負、正の屈折力を有する第１、第２、第３レンズ群と、それに続く１つ以上のレンズ群を含む後群を有するポジティブリード型のズームレンズが知られている。ポジティブリード型のズームレンズとして、物体側より像側へ順に、正、負、正、正の屈折力の４つのレンズ群より成るズームレンズが知られている（特許文献１）。 In recent years, the entire apparatus of an imaging apparatus such as a video camera using a solid-state imaging device, a digital still camera, a broadcasting camera, a surveillance camera, and a camera using a silver salt film has been downsized. A photographing optical system used therefor is required to be a zoom lens having a short overall lens length, a compact size, a high zoom ratio (high zoom ratio), and a high resolution. A zoom lens that meets these requirements includes a first, second, and third lens group having positive, negative, and positive refractive power in order from the object side to the image side, followed by one or more lens groups. A positive lead type zoom lens having a group is known. As a positive lead type zoom lens, there is known a zoom lens including four lens groups of positive, negative, positive, and positive refractive power in order from the object side to the image side (Patent Document 1).
特許文献１では第１レンズ群の正レンズに低分散な材料を用いて望遠側において色収差の補正を良好に行っている。又、物体側より像側へ順に正、負、正、正、正の屈折力の５つのレンズ群より成るズームレンズが知られている（特許文献２）。又、物体側より像側へ順に正、負、正、負、正の屈折力の５つのレンズ群より成るズームレンズが知られている（特許文献３）。特許文献３ではズーム比１０程度のズームレンズを開示している。 In Patent Document 1, chromatic aberration is favorably corrected on the telephoto side by using a low-dispersion material for the positive lens of the first lens group. In addition, there is known a zoom lens including five lens groups having positive, negative, positive, positive, and positive refractive powers in order from the object side to the image side (Patent Document 2). In addition, there is known a zoom lens including five lens groups having positive, negative, positive, negative, and positive refractive power in order from the object side to the image side (Patent Document 3). Patent Document 3 discloses a zoom lens having a zoom ratio of about 10.
一般にズームレンズを所定のズーム比で全系を小型化するためには、ズームレンズを構成する各レンズ群の屈折力（光学的パワー＝焦点距離の逆数）を強めつつ、レンズ枚数を削減すれば良い。しかしながら、このようにしたズームレンズは、ズーミングに伴う収差変動が大きくなり、全ズーム範囲にわたり高い光学性能を得るのが難しくなる。特に前玉有効径が増大し、レンズ系全体の小型化が不十分になってくる。また、同時に望遠端における色収差などの諸収差の補正が困難になってくる。 In general, in order to reduce the size of a zoom lens with a predetermined zoom ratio, the number of lenses can be reduced while increasing the refractive power (optical power = reciprocal of focal length) of each lens group constituting the zoom lens. good. However, in such a zoom lens, aberration fluctuations accompanying zooming increase, and it becomes difficult to obtain high optical performance over the entire zoom range. In particular, the effective diameter of the front lens increases and the entire lens system is not sufficiently miniaturized. At the same time, it becomes difficult to correct various aberrations such as chromatic aberration at the telephoto end.
前述した４群ズームレンズや５群ズームレンズにおいて、高ズーム比とレンズ系全体の小型化を図りつつ、良好な光学性能を得るには各レンズ群の屈折力やレンズ構成、そして各レンズ群のズーミングに伴う移動条件等を適切に設定することが重要となる。特に第１、第２レンズ群のレンズ構成やズーミングに際しての第１、第３レンズ群の移動条件等を適切に設定することが重要になってくる。これらの構成を適切に設定しないと、全系の小型化を図りつつ、高ズーム比で高い光学性能のズームレンズを得るのが難しくなってくる。 In the above-described four-group zoom lens and five-group zoom lens, in order to obtain good optical performance while achieving a high zoom ratio and downsizing of the entire lens system, the refractive power of each lens group, the lens configuration, and each lens group It is important to appropriately set the movement conditions associated with zooming. In particular, it is important to appropriately set the lens configuration of the first and second lens groups and the movement conditions of the first and third lens groups during zooming. If these configurations are not set appropriately, it becomes difficult to obtain a zoom lens having a high zoom ratio and high optical performance while reducing the size of the entire system.
本発明は、光学系全体が小型で、高ズーム比で、しかも全ズーム範囲にわたり高い光学
性能が得られるズームレンズ及びそれを有する撮像装置の提供を目的とする。
SUMMARY OF THE INVENTION An object of the present invention is to provide a zoom lens and an image pickup apparatus having the zoom lens in which the entire optical system is small, has a high zoom ratio, and provides high optical performance over the entire zoom range.
本発明のズームレンズは、物体側より像側へ順に、正の屈折力の第１レンズ群、負の屈折力の第２レンズ群、正の屈折力の第３レンズ群、負の屈折力の第４レンズ群、正の屈折力の第５レンズ群から構成され、
広角端に対して望遠端において前記第１レンズ群と前記第２レンズ群の間隔が増大し、前記第２レンズ群と前記第３レンズ群の間隔が減少し、前記第３レンズ群と前記第４レンズ群の間隔が変化し、前記第４レンズ群と前記第５レンズ群の間隔が変化するズームレンズであって、
前記第１レンズ群は正レンズと負レンズを含み、前記第１レンズ群に含まれる正レンズは２つであり、前記第２レンズ群は負レンズ、正レンズを有し、前記第１レンズ群を構成する正レンズのうち材料のアッベ数が最も大きい正レンズの材料のアッベ数をν１ｐ、前記第２レンズ群の１つの正レンズの材料の屈折率とアッベ数を各々Ｎ２ｐ、ν２ｐ、前記第１レンズ群の焦点距離をｆ１、前記第１レンズ群を構成する正レンズのうち材料のアッベ数が最も大きい正レンズの焦点距離をｆ１ｐ、前記第１レンズ群を構成する２つの正レンズの材料の屈折率の差をΔＮ１ｐとするとき、
８０．０＜ν１ｐ
１．０＜ｆ１ｐ／ｆ１＜１．６
ν２ｐ≦１８．０
１．９０＜Ｎ２ｐ
０．１０３＜ΔＮ１ｐ≦０．２００
なる条件を満足することを特徴としている。
The zoom lens according to the present invention includes, in order from the object side to the image side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, a third lens group having a positive refractive power, and a negative lens having a negative refractive power. A fourth lens group, and a fifth lens group having a positive refractive power;
The distance between the first lens group and the second lens group is increased at the telephoto end with respect to the wide-angle end, the distance between the second lens group and the third lens group is decreased, and the third lens group and the third lens group are reduced. A zoom lens in which an interval between four lens groups is changed and an interval between the fourth lens group and the fifth lens group is changed;
The first lens group includes a positive lens and a negative lens, the positive lens included in the first lens group is two, the second lens group includes a negative lens and a positive lens, and the first lens group Of the positive lens having the largest Abbe number of the material among the positive lenses constituting ν1p, the refractive index and Abbe number of the material of one positive lens of the second lens group are N2p and ν2p, respectively. The focal length of one lens group is f1, the focal length of the positive lens having the largest Abbe number of the material among the positive lenses constituting the first lens group is f1p, and the materials of the two positive lenses constituting the first lens group When the difference in refractive index is ΔN1p,
80.0 <ν1p
1.0 <f1p / f1 <1.6
ν2p ≦ 18.0
1.90 <N2p
0.103 <ΔN1p ≦ 0. 200
It is characterized by satisfying the following conditions.
本発明によれば、光学系全体が小型で、高ズーム比で、しかも全ズーム範囲にわたり高い光学性能が得られるズームレンズが得られる。 According to the present invention, it is possible to obtain a zoom lens in which the entire optical system is small, has a high zoom ratio, and high optical performance over the entire zoom range.
以下に、本発明の好ましい実施の形態を、添付の図面に基づいて詳細に説明する。本発明のズームレンズは、物体側より像側へ順に、正の屈折力の第１レンズ群、負の屈折力の第２レンズ群、正の屈折力の第３レンズ群、１以上のレンズ群を含む後群を有している。ズーミングに際しては広角端に対して望遠端において第１レンズ群と第２レンズ群の間隔が増大し、第２レンズ群と第３レンズ群の間隔が減少し、第３レンズ群と後群の間隔が変化する。 Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The zoom lens of the present invention includes, in order from the object side to the image side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, a third lens group having a positive refractive power, and one or more lens groups. Having a rear group. During zooming, the distance between the first lens group and the second lens group increases at the telephoto end with respect to the wide-angle end, the distance between the second lens group and the third lens group decreases, and the distance between the third lens group and the rear group. Changes.
図１（Ａ）、（Ｂ）、（Ｃ）は、本発明の実施例１のズームレンズの広角端（短焦点距離端）、中間のズーム位置、望遠端（長焦点距離端）におけるレンズ断面図である。図２（Ａ）、（Ｂ）、（Ｃ）は実施例１のズームレンズの広角端、中間のズーム位置、望遠端における収差図である。実施例１はズーム比１３．３２、開口比３．２１〜６．０８のズームレンズである。 FIGS. 1A, 1B, and 1C show lens cross sections at the wide-angle end (short focal length end), the intermediate zoom position, and the telephoto end (long focal length end) of the zoom lens according to Embodiment 1 of the present invention. FIG. 2A, 2B, and 2C are aberration diagrams at the wide-angle end, the intermediate zoom position, and the telephoto end of the zoom lens according to the first exemplary embodiment. The first embodiment is a zoom lens having a zoom ratio of 13.32 and an aperture ratio of 3.21 to 6.08.
図３（Ａ）、（Ｂ）、（Ｃ）は、本発明の参考例１のズームレンズの広角端、中間のズーム位置、望遠端におけるレンズ断面図である。図４（Ａ）、（Ｂ）、（Ｃ）は参考例１のズームレンズの広角端、中間のズーム位置、望遠端における収差図である。参考例１はズーム比１１．４１、開口比３．４３〜５．７２のズームレンズである。 3A, 3B, and 3C are lens cross-sectional views at the wide-angle end, the intermediate zoom position, and the telephoto end of the zoom lens according to Reference Example 1 of the present invention. 4A, 4B, and 4C are aberration diagrams of the zoom lens of Reference Example 1 at the wide-angle end, the intermediate zoom position, and the telephoto end. Reference Example 1 is a zoom lens having a zoom ratio of 11.41 and an aperture ratio of 3.43 to 5.72.
図５（Ａ）、（Ｂ）、（Ｃ）は、本発明の参考例２のズームレンズの広角端、中間のズーム位置、望遠端におけるレンズ断面図である。図６（Ａ）、（Ｂ）、（Ｃ）は参考例２のズームレンズの広角端、中間のズーム位置、望遠端における収差図である。参考例２はズーム比１３．８２、開口比３．３６〜６．０９のズームレンズである。 5A, 5B, and 5C are lens cross-sectional views at the wide-angle end, the intermediate zoom position, and the telephoto end of the zoom lens according to Reference Example 2 of the present invention. 6A, 6B, and 6C are aberration diagrams of the zoom lens of Reference Example 2 at the wide-angle end, the intermediate zoom position, and the telephoto end. Reference Example 2 is a zoom lens having a zoom ratio of 13.82 and an aperture ratio of 3.36 to 6.09.
図７（Ａ）、（Ｂ）、（Ｃ）は、本発明の実施例２のズームレンズの広角端、中間のズーム位置、望遠端におけるレンズ断面図である。図８（Ａ）、（Ｂ）、（Ｃ）は実施例２のズームレンズの広角端、中間のズーム位置、望遠端における収差図である。実施例２はズーム比１３．５４、開口比３．３７〜６．０９のズームレンズである。 7A, 7B, and 7C are lens cross-sectional views at the wide-angle end, the intermediate zoom position, and the telephoto end of the zoom lens according to Embodiment 2 of the present invention. 8A, 8B, and 8C are aberration diagrams at the wide-angle end, the intermediate zoom position, and the telephoto end of the zoom lens according to the second embodiment. The second embodiment is a zoom lens having a zoom ratio of 13.54 and an aperture ratio of 3.37 to 6.09.
図９（Ａ）、（Ｂ）、（Ｃ）は、本発明の参考例３のズームレンズの広角端、中間のズーム位置、望遠端におけるレンズ断面図である。図１０（Ａ）、（Ｂ）、（Ｃ）は参考例３のズームレンズの広角端、中間のズーム位置、望遠端における収差図である。参考例３はズーム比１２．２７、開口比３．５０〜５．９７のズームレンズである。 9A, 9B, and 9C are lens cross-sectional views at the wide-angle end, the intermediate zoom position, and the telephoto end of the zoom lens according to Reference Example 3 of the present invention. 10A, 10B, and 10C are aberration diagrams of the zoom lens of Reference Example 3 at the wide-angle end, the intermediate zoom position, and the telephoto end. Reference Example 3 is a zoom lens having a zoom ratio of 12.27 and an aperture ratio of 3.50 to 5.97.
図１１は本発明のズームレンズを備えるカメラ（撮像装置）の要部概略図である。各実施例のズームレンズはビデオカメラやデジタルカメラ、そして銀塩フィルムカメラ等の撮像装置に用いられる撮影レンズ系である。レンズ断面図において、左方が物体側、右方が像側である。またｉは物体側から像側への各レンズ群の順序を示し、Ｌｉは第ｉレンズ群である。Ｌｒは１以上のレンズ群を含む後群である。 FIG. 11 is a schematic diagram of a main part of a camera (image pickup apparatus) including the zoom lens according to the present invention. The zoom lens according to each embodiment is a photographing lens system used in an imaging apparatus such as a video camera, a digital camera, and a silver salt film camera. In the lens cross-sectional view, the left side is the object side, and the right side is the image side. Further, i indicates the order of the lens groups from the object side to the image side, and Li is the i-th lens group. Lr is a rear group including one or more lens groups.
図１、図５、図７の実施例１、参考例２、実施例２のレンズ断面図において、Ｌ１は正の屈折力（光学的パワー＝焦点距離の逆数）の第１レンズ群、Ｌ２は負の屈折力の第２レンズ群、Ｌ３は正の屈折力の第３レンズ群である。後群Ｌｒは負の屈折力の第４レンズ群Ｌ４、正の屈折力の第５レンズ群Ｌ５より成っている。実施例１、参考例２、実施例２はポジティブリード型の５群ズームレンズである。 In the lens cross-sectional views of Example 1, Reference Example 2, and Example 2 in FIGS. 1, 5, and 7, L1 is a first lens unit having positive refractive power (optical power = reciprocal of focal length), and L2 is The second lens unit having a negative refractive power, L3 is a third lens unit having a positive refractive power. The rear group Lr includes a fourth lens unit L4 having a negative refractive power and a fifth lens unit L5 having a positive refractive power. Example 1, Reference Example 2, and Example 2 are positive lead type 5-group zoom lenses.
図３の参考例１のレンズ断面図においてＬ１は正の屈折力の第１レンズ群、Ｌ２は負の屈折力の第２レンズ群、Ｌ３は正の屈折力の第３レンズ群である。後群Ｌｒは正の屈折力の第４レンズ群Ｌ４より成っている。参考例１はポジティブリード型の４群ズームレンズである。 In the lens cross-sectional view of Reference Example 1 in FIG. 3, L1 is a first lens group having a positive refractive power, L2 is a second lens group having a negative refractive power, and L3 is a third lens group having a positive refractive power. The rear group Lr includes a fourth lens unit L4 having a positive refractive power. Reference Example 1 is a positive lead type four-group zoom lens.
図９の参考例３のレンズ断面図においてＬ１は正の屈折力の第１レンズ群、Ｌ２は負の屈折力の第２レンズ群、Ｌ３は正の屈折力の第３レンズ群である。後群Ｌｒは正の屈折力の第４レンズ群Ｌ４、正の屈折力の第５レンズ群Ｌ５より成っている。参考例３はポジティブリード型の５群ズームレンズである。各レンズ断面図においてＳＰは開放Ｆナンバー（Ｆｎｏ）光束を決定（制限）する開口絞りの作用をするＦナンバー決定部材（以下「開口絞り」ともいう。）である。 In the lens cross-sectional view of Reference Example 3 in FIG. 9, L1 is a first lens group having a positive refractive power, L2 is a second lens group having a negative refractive power, and L3 is a third lens group having a positive refractive power. The rear group Lr includes a fourth lens unit L4 having a positive refractive power and a fifth lens unit L5 having a positive refractive power. Reference Example 3 is a positive lead type 5-group zoom lens. In each lens cross-sectional view, SP is an F-number determining member (hereinafter also referred to as “aperture stop”) that functions as an aperture stop that determines (limits) an open F-number (Fno) light beam.
Ｇは光学フィルター、フェースプレート、水晶ローパスフィルター、赤外カットフィルター等に相当する光学ブロックである。ＩＰは像面であり、ビデオカメラやデジタルスチルカメラの撮影光学系として使用する際にはＣＣＤセンサやＣＭＯＳセンサ等の固体撮像素子（光電変換素子）の撮像面が置かれる。又、銀塩フィルム用カメラの撮影光学系として使用する際にはフィルム面に相当する感光面が置かれている。球面収差図において、実線のｄはｄ線、２点鎖線のｇはｇ線を示す。非点収差図において点線のΔＭはメリディオナル像面、実線のΔＳはサジタル像面、倍率色収差はｇ線によって表している。ωは半画角（撮影画角の半分の値）、ＦｎｏはＦナンバーである。尚、以下の各実施例において広角端と望遠端は変倍用レンズ群が機構上光軸上を移動可能な範囲の両端に位置したときのズーム位置をいう。各実施例において矢印は、広角端から望遠端へのズーミング又はフォーカスに際しての移動軌跡を示している。 G is an optical block corresponding to an optical filter, a face plate, a quartz low-pass filter, an infrared cut filter, or the like. IP is an image plane, and when used as a photographing optical system of a video camera or a digital still camera, an imaging plane of a solid-state imaging device (photoelectric conversion device) such as a CCD sensor or a CMOS sensor is placed. Further, when used as a photographing optical system for a silver salt film camera, a photosensitive surface corresponding to the film surface is provided. In the spherical aberration diagram, the solid line d indicates the d line, and the two-dot chain line g indicates the g line. In the astigmatism diagram, the dotted line ΔM is represented by the meridional image plane, the solid line ΔS is represented by the sagittal image plane, and the lateral chromatic aberration is represented by the g line. ω is a half angle of view (a value half the shooting angle of view), and Fno is an F number. In the following embodiments, the wide-angle end and the telephoto end refer to zoom positions when the zoom lens unit is positioned at both ends of a range in which the mechanism can move on the optical axis. In each embodiment, an arrow indicates a movement locus during zooming or focusing from the wide-angle end to the telephoto end.
各実施例のズームレンズでは、第１レンズ群Ｌ１と第２レンズ群Ｌ２の屈折力をある程度強めることで広角端において第１レンズ群Ｌ１と開口絞りＳＰの距離を小さくしている。これにより第１レンズ群Ｌ１のレンズ径の小型化が図っている。また第３レンズ群Ｌ３の屈折力をある程度強めることで開口絞りＳＰから像面ＩＰまでの距離を小さく（短く）している。これにより広角端におけるレンズ全長（第１レンズ面から像面までの長さ）を短縮している。 In the zoom lens of each embodiment, the distance between the first lens unit L1 and the aperture stop SP is reduced at the wide angle end by increasing the refractive power of the first lens unit L1 and the second lens unit L2 to some extent. As a result, the lens diameter of the first lens unit L1 is reduced. Further, the distance from the aperture stop SP to the image plane IP is reduced (shortened) by increasing the refractive power of the third lens unit L3 to some extent. This shortens the total lens length (the length from the first lens surface to the image plane) at the wide-angle end.
各実施例のズームレンズでは、広角端から望遠端へのズーミングに際して第１レンズ群Ｌ１を物体側に移動させ、広角端よりも望遠端において第１レンズ群Ｌ１と第２レンズ群Ｌ２の間隔を広げる（増大）ことで変倍作用を得ている。さらに広角端から望遠端へのズーミングに際して第３レンズ群Ｌ３を物体側に移動させ広角端よりも望遠端において第２レンズ群Ｌ２と第３レンズ群Ｌ３の間隔を狭める（減少）ことで変倍作用を得ている。 In the zoom lens of each embodiment, the first lens unit L1 is moved to the object side during zooming from the wide-angle end to the telephoto end, and the distance between the first lens unit L1 and the second lens unit L2 is set at the telephoto end rather than the wide-angle end. By zooming in (increasing), the zooming effect is obtained. Further, during zooming from the wide-angle end to the telephoto end, the third lens unit L3 is moved to the object side, and the distance between the second lens unit L2 and the third lens unit L3 is reduced (decreased) at the telephoto end rather than the wide-angle end. Has an effect.
このように変倍作用を複数の箇所（レンズ群）で分担することにより高ズーム比としながら変倍のための各レンズ群の移動ストロークが短縮されるとともに望遠端においてレンズ全長を短縮している。変倍に伴うピント変動は最も像側のレンズ群が物体側へ凸状の軌跡を描いて移動することで補正している。フォーカシングについては第１レンズ群Ｌ１もしくは最も像側のレンズ群を物体側に移動させることで無限遠物体から近距離物体への合焦を行っている。 By sharing the zooming action at a plurality of locations (lens groups) in this way, the moving stroke of each lens group for zooming is shortened and the total lens length is shortened at the telephoto end while maintaining a high zoom ratio. . The focus variation caused by zooming is corrected by moving the most image side lens unit in a convex locus toward the object side. For focusing, the first lens unit L1 or the lens unit closest to the image side is moved to the object side to focus from an object at infinity to a near object.
図１、図５、図７、図９の５群ズームレンズでは望遠端において無限遠物体から近距離物体へフォーカスを行う場合には各レンズ断面図の矢印５ｃに示すように第５レンズ群Ｌ５を前方に繰り出すことによって行っている。第５レンズ群Ｌ５に関する実線の曲線５ａと点線の曲線５ｂは各々無限遠物体と近距離物体にフォーカスしているときの広角端から望遠端へのズーミングに伴う際の像面変動を補正するための移動軌跡を示している。 In the 5-group zoom lens of FIGS. 1, 5, 7, and 9, when focusing from an infinite object to a close object at the telephoto end, as shown by an arrow 5c in each lens sectional view, the fifth lens group L5. This is done by feeding it forward. A solid curve 5a and a dotted curve 5b relating to the fifth lens unit L5 are for correcting image plane fluctuations during zooming from the wide-angle end to the telephoto end when focusing on an object at infinity and a short-distance object, respectively. The movement trajectory is shown.
図３の参考例１では望遠端において無限遠物体から近距離物体へフォーカスを行う場合にはレンズ断面図の矢印４ｃに示すように第４レンズ群Ｌ４を前方に繰り出すことによって行っている。第４レンズ群Ｌ４に関する実線の曲線４ａと点線の曲線４ｂは各々無限遠物体と近距離物体にフォーカスしているときの広角端から望遠端へのズーミングに伴う際の像面変動を補正するための移動軌跡を示している。 In Reference Example 1 in FIG. 3, when focusing from an infinitely distant object to a close object at the telephoto end, the fourth lens unit L4 is extended forward as indicated by an arrow 4c in the lens sectional view. A solid curve 4a and a dotted curve 4b relating to the fourth lens unit L4 are for correcting image plane fluctuations during zooming from the wide-angle end to the telephoto end when focusing on an object at infinity and a short-distance object, respectively. The movement trajectory is shown.
各実施例では第１レンズ群Ｌ１は２つの正レンズと、１つの負レンズを有している。第２レンズ群Ｌ２は負レンズ、正レンズを有している。第１レンズ群Ｌ１に含まれる正レンズのうち、材料のアッベ数が最も大きい正レンズＧ１ｐの材料のアッベ数をν１ｐとする。第２レンズ群Ｌ２の１つの正レンズの材料の屈折率とアッベ数を各々Ｎ２ｐ、ν２ｐとする。第１レンズ群Ｌ１の焦点距離をｆ１、第１レンズ群Ｌ１の正レンズのうち材料のアッベ数が最も大きい正レンズＧ１ｐの焦点距離をｆ１ｐとする。このとき、
８０．０＜ν１ｐ・・・・・・・・・・（１）
１．０＜ｆ１ｐ／ｆ１＜１．６・・・・（２）
ν２ｐ≦１８．０・・・・・・・・・・（３）
１．９０＜Ｎ２ｐ・・・・・・・・・・（４）
なる条件を満足している。
In each embodiment, the first lens unit L1 has two positive lenses and one negative lens. The second lens unit L2 has a negative lens and a positive lens. Of the positive lenses included in the first lens unit L1, the Abbe number of the material of the positive lens G1p having the largest material Abbe number is denoted by ν1p. The refractive index and Abbe number of one positive lens material of the second lens unit L2 are N2p and ν2p, respectively. The focal length of the first lens unit L1 is f1, and the focal length of the positive lens G1p having the largest Abbe number of the material among the positive lenses of the first lens unit L1 is f1p. At this time,
80.0 <ν1p (1)
1.0 <f1p / f1 <1.6 (2)
ν2p ≦ 18.0 (3)
1.90 <N2p (4)
Is satisfied.
条件式（１）は第１レンズ群Ｌ１の含まれる正レンズのうち、材料のアッベ数が最も大きい正レンズＧ１Ｐの材料のアッベ数を規定する式である。条件式（１）の下限を超えてアッベ数が小さすぎると、すなわち分散が大きいと望遠側において軸上色収差と倍率色収差を良好に補正するのが困難となる。条件式（１）を満足するようなアッベ数が８０を越える低分散材料は部分分散比が大きい傾向があるため望遠側において二次スペクトルを良好に補正する効果も有する。このような効果を得るためにも条件式（１）の下限を超えないことが好ましい。 Conditional expression (1) defines the Abbe number of the material of the positive lens G1P having the largest material Abbe number among the positive lenses included in the first lens unit L1. If the lower limit of conditional expression (1) is exceeded and the Abbe number is too small, that is, if the dispersion is large, it is difficult to correct axial chromatic aberration and lateral chromatic aberration well on the telephoto side. A low dispersion material with an Abbe number exceeding 80 that satisfies the conditional expression (1) tends to have a large partial dispersion ratio, and therefore has an effect of favorably correcting the secondary spectrum on the telephoto side. In order to obtain such an effect, it is preferable not to exceed the lower limit of conditional expression (1).
条件式（２）は第１レンズ群Ｌ１の正レンズのうち、材料のアッベ数が最も大きい正レンズＧ１Ｐの焦点距離を規定する式である。条件式（２）の上限を超えて正レンズＧ１Ｐの焦点距離が大きすぎると、すなわち屈折力が弱すぎると、正レンズＧ１Ｐに低分散材料を用いても望遠側において軸上色収差と倍率色収差を良好に補正するのが困難になる。また条件式（２）の下限を超えて正レンズＧ１Ｐの焦点距離が小さすぎると、すなわち屈折力がきつすぎると正レンズＧ１Ｐより望遠側において球面収差が多く発生してくるので良くない。 Conditional expression (2) is an expression that defines the focal length of the positive lens G1P having the largest Abbe number of the material among the positive lenses of the first lens unit L1. If the upper limit of conditional expression (2) is exceeded and the focal length of the positive lens G1P is too large, that is, if the refractive power is too weak, axial chromatic aberration and lateral chromatic aberration will occur on the telephoto side even if a low dispersion material is used for the positive lens G1P. It becomes difficult to correct well. If the focal length of the positive lens G1P is too small beyond the lower limit of the conditional expression (2), that is, if the refractive power is too strong, more spherical aberration occurs on the telephoto side than the positive lens G1P, which is not good.
条件式（３）は第２レンズ群Ｌ２に含まれる１つの正レンズＧ２Ｐのアッベ数を規定する式である。上限を越えるとすなわち分散が小さいと第２レンズ群Ｌ２中の負レンズの材料とのアッベ数の差を十分取ることができず色消しに必要な各レンズの屈折力が強まってしまう。結果として第２レンズ群Ｌ２が大型化してくる。また広角側において歪曲収差、像面彎曲、望遠側において球面収差が多く発生してくるので良くない。 Conditional expression (3) defines the Abbe number of one positive lens G2P included in the second lens unit L2. If the upper limit is exceeded, that is, if the dispersion is small, a sufficient difference in Abbe number from the material of the negative lens in the second lens unit L2 cannot be obtained, and the refractive power of each lens necessary for achromaticity will increase. As a result, the second lens unit L2 becomes larger. Further, a large amount of distortion aberration, field curvature, and spherical aberration occur on the telephoto side on the wide angle side, which is not good.
条件式（４）は第２レンズ群Ｌ２に含まれる１つの正レンズＧ２Ｐの材料の屈折率を規定する式である。下限を越えて屈折率が小さすぎると所望の屈折力を得るためのレンズ面の曲率がきつくなりレンズ厚みが増大してくるので良くない。またペッツバール和が正の方向に大きくなりすぎ像面彎曲が多く発生してくるので良くない。第２レンズ群Ｌ２の小型化と諸収差の補正を良好に行うには条件式（３）、（４）をともに満足するのが好ましい。各実施例において更に好ましくは条件式（１）乃至（４）の数値を次の如く設定するのが良い。 Conditional expression (4) defines the refractive index of the material of one positive lens G2P included in the second lens unit L2. If the refractive index is too small beyond the lower limit, the curvature of the lens surface for obtaining a desired refractive power becomes tight and the lens thickness increases, which is not good. In addition, the Petzval sum becomes too large in the positive direction, and a lot of field curvature occurs, which is not good. In order to satisfactorily reduce the size of the second lens unit L2 and correct various aberrations, it is preferable that both conditional expressions (3) and (4) are satisfied. In each embodiment, it is more preferable to set the numerical values of the conditional expressions (1) to (4) as follows.
８１．０＜ν１ｐ・・・・・・・・・・・・・・（１ａ）
１．０００＜ｆ１ｐ／ｆ１＜１．５９５・・・・（２ａ）
ν２ｐ≦１８．０・・・・・・・・・・・・・・（３ａ）
１．９２＜Ｎ２ｐ・・・・・・・・・・・・・・（４ａ）
以上のように各実施例によれば、ズーム比が１２程度以上の高ズーム比としながら前玉有効径の小型化を容易とし、望遠側において色収差を良好の補正したズームレンズが得られる。各実施例において、更に好ましくは次の諸条件のうち１以上を満足するのが良い。
81.0 <ν1p (1a)
1.000 <f1p / f1 <1.595 (2a)
ν2p ≦ 18.0 (3a)
1.92 <N2p (4a)
As described above, according to each embodiment, it is possible to easily reduce the effective diameter of the front lens while maintaining a high zoom ratio of about 12 or more, and to obtain a zoom lens that corrects chromatic aberration well on the telephoto side. In each embodiment, it is more preferable to satisfy one or more of the following conditions.
第１レンズ群Ｌ１と第３レンズ群Ｌ３の広角端から望遠端へのズーミングにおける移動量を各々Ｍ１、Ｍ３とする。広角端における全系の焦点距離をｆｗとする。第２レンズ群Ｌ２と第３レンズ群Ｌ３の焦点距離を各々ｆ２、ｆ３とする。第１レンズ群Ｌ１の２つの正レンズの材料の屈折率の差をΔＮ１ｐとする。第２レンズ群Ｌ２は物体側から像側へ順に、屈折力の絶対値が物体側に比べ像側のレンズ面が大きく、像側に凹面を向けた負レンズと物体側に凸面を向けた正レンズを有している。そして負レンズの像側のレンズ面から正レンズの物体側のレンズ面までの光軸上の距離をｄ２とする。第２レンズ群Ｌ２に含まれる屈折力の絶対値が最も大きい負レンズの材料のアッベ数をν２ｎとする。このとき、
−６．５＜Ｍ１／ｆｗ＜−４．０・・・・・・・・・・・・・（５）
−４．０＜Ｍ３／ｆｗ＜−２．７・・・・・・・・・・・・・（６）
７．０＜ｆ１／ｆｗ＜１０．０・・・・・・・・・・・・・・（７）
１．２＜｜ｆ２｜／ｆｗ＜１．６・・・・・・・・・・・・・（８）
１．７＜ｆ３／ｆｗ＜４．６・・・・・・・・・・・・・・・（９）
０．１０３＜ΔＮ１ｐ≦０．２００・・・・・・・・・・・・（１０）
０．５２＜ｄ２／ｆｗ＜１．００・・・・・・・・・・・・（１１）
０．０２９＜（１／ν２ｐ−１／ν２ｎ）＜０．０５０・・（１２）
なる条件のうち１以上を満足するのが良い。ここで移動量Ｍ１，Ｍ３は広角端に比べ望遠端での光軸方向の像面に対する各レンズ群の位置の差であり、符号は物体側に位置するときを負、像側に位置するときを正とする。
The movement amounts in zooming from the wide-angle end to the telephoto end of the first lens unit L1 and the third lens unit L3 are M1 and M3, respectively. Let fw be the focal length of the entire system at the wide-angle end. The focal lengths of the second lens unit L2 and the third lens unit L3 are defined as f2 and f3, respectively. A difference in refractive index between the materials of the two positive lenses of the first lens unit L1 is ΔN1p. In the second lens unit L2, in order from the object side to the image side, the absolute value of the refractive power is larger on the image side than on the object side, and a negative lens having a concave surface on the image side and a positive lens having a convex surface on the object side. Has a lens. The distance on the optical axis from the image side lens surface of the negative lens to the object side lens surface of the positive lens is d2. The Abbe number of the material of the negative lens having the largest absolute value of refractive power included in the second lens unit L2 is denoted by ν2n. At this time,
−6.5 <M1 / fw <−4.0 (5)
-4.0 <M3 / fw <-2.7 (6)
7.0 <f1 / fw <10.0 (7)
1.2 <| f2 | / fw <1.6 (8)
1.7 <f3 / fw <4.6 (9)
0.103 <ΔN1p ≦ 0. 200 ... (10)
0.52 <d2 / fw <1.00 (11)
0.029 <(1 / ν2p−1 / ν2n) <0.050 (12)
It is preferable to satisfy one or more of the following conditions. Here, the movement amounts M1 and M3 are the difference in position of each lens group with respect to the image plane in the optical axis direction at the telephoto end compared to the wide-angle end, and the sign is negative when positioned on the object side and when positioned on the image side Is positive.
次に前述の各条件式の技術的意味について説明する。条件式（５）は第１レンズ群Ｌ１のズーミングに伴う移動量を規定する式である。条件式（５）の上限を超えてズーミングの際の物体側への移動量が小さすぎると変倍作用が弱まる。第１レンズ群Ｌ１の屈折力を強めてこのときの変倍作用を補おうとすると望遠側において球面収差が多く発生してくる。また第２レンズ群Ｌ２の屈折力を強めて変倍作用を補おうとすると広角側において像面彎曲、望遠側において球面収差が多く発生してくる。条件式（５）の下限を超えてズーミングの際の物体側への移動量が大きすぎると望遠端においてレンズ全長が増大し、全系の小型化が困難になる。 Next, the technical meaning of each conditional expression described above will be described. Conditional expression (5) is an expression that defines the amount of movement associated with zooming of the first lens unit L1. If the amount of movement to the object side during zooming is too small beyond the upper limit of conditional expression (5), the zooming action is weakened. If the refractive power of the first lens unit L1 is increased to compensate for the zooming action at this time, a large amount of spherical aberration occurs on the telephoto side. Further, when the refractive power of the second lens unit L2 is increased to compensate for the zooming action, a large amount of spherical aberration occurs on the wide-angle side and on the telephoto side. If the lower limit of conditional expression (5) is exceeded and the amount of movement toward the object side during zooming is too large, the total lens length increases at the telephoto end, making it difficult to downsize the entire system.
条件式（６）は第３レンズ群Ｌ３のズーミングの際の移動量を規定する式である。条件式（６）の上限を超えてズーミングの際の物体側への移動量が小さすぎると、変倍作用が弱まる。第１レンズ群Ｌ１の屈折力を強めてこのときの変倍作用を補おうとすると望遠側において球面収差が多く発生してくる。また第２レンズ群の屈折力を強めて変倍作用を補おうとすると広角側において像面彎曲、望遠側において球面収差が多く発生してくる。条件式（６）の下限を超えて物体側への移動量が大きすぎると第３レンズ群Ｌ３とともに移動する開口絞りＳＰの移動も大きくなる。これにより変倍に伴う開放Ｆナンバーの変化が大きくなり望遠端のＦナンバーが暗くなるので良くない。画素ピッチの小さい固体撮像素子を用いる場合には撮影レンズには高周波のＭＴＦが高いことが求められる。開放Ｆナンバーが暗いと回折の影響によりＭＴＦを上げることが困難となるので良くない。 Conditional expression (6) is an expression that defines the amount of movement of the third lens unit L3 during zooming. If the amount of movement to the object side during zooming is too small beyond the upper limit of conditional expression (6), the zooming action is weakened. If the refractive power of the first lens unit L1 is increased to compensate for the zooming action at this time, a large amount of spherical aberration occurs on the telephoto side. Further, when the refractive power of the second lens group is increased to compensate for the zooming effect, a large amount of field aberration occurs on the wide angle side and spherical aberration occurs on the telephoto side. If the amount of movement toward the object side exceeds the lower limit of conditional expression (6), the movement of the aperture stop SP that moves together with the third lens unit L3 also increases. As a result, the change in the open F number accompanying zooming becomes large and the F number at the telephoto end becomes dark, which is not good. When a solid-state imaging device with a small pixel pitch is used, the photographing lens is required to have a high frequency MTF. If the open F number is dark, it is difficult to increase the MTF due to the influence of diffraction, which is not good.
条件式（７）は第１レンズ群Ｌ１の焦点距離すなわち屈折力を規定する式である。条件式（７）の上限を超えて屈折力が弱すぎると変倍作用が弱まる。第１レンズ群Ｌ１のズーミングの際の移動量を増やしてこのときの変倍作用を補おうとすると望遠端においてレンズ全長が増大してくる。また第３レンズ群Ｌ３の屈折力を強めて変倍作用を補おうとすると球面収差、コマ収差、軸上色収差等の諸収差の発生が多くなってくる。このときの諸収差の補正のためにレンズ枚数を増加するとレンズ群の厚みが増大し小型化が困難となる。条件式（７）の下限を超えて屈折力が強すぎると第１レンズ群Ｌ１より望遠側において球面収差が多く発生してくる。このときの収差補正のためにレンズ枚数を増加すると第１レンズ群が大型化し、前玉径が増大するので好ましくない。 Conditional expression (7) defines the focal length, that is, the refractive power of the first lens unit L1. If the upper limit of conditional expression (7) is exceeded and the refractive power is too weak, the zooming action is weakened. If the amount of movement of the first lens unit L1 during zooming is increased to compensate for the zooming action at this time, the total lens length increases at the telephoto end. In addition, when the refractive power of the third lens unit L3 is increased to compensate for the zooming action, various aberrations such as spherical aberration, coma aberration, and longitudinal chromatic aberration increase. If the number of lenses is increased in order to correct various aberrations at this time, the thickness of the lens group increases and it becomes difficult to reduce the size. If the lower limit of conditional expression (7) is exceeded and the refractive power is too strong, more spherical aberration occurs on the telephoto side than the first lens unit L1. Increasing the number of lenses for aberration correction at this time is not preferable because the first lens group becomes larger and the front lens diameter increases.
条件式（８）は第２レンズ群Ｌ２の焦点距離すなわち屈折力を規定する式である。条件式（８）の上限を超えて屈折力が弱すぎると第２レンズ群Ｌ２の変倍作用が薄れ所望の変倍比を得るのが困難になる。また条件式（８）の下限を超えて屈折力が強すぎると第２レンズ群Ｌ２より広角側において像面彎曲、望遠側において球面収差が多く発生してくる。 Conditional expression (8) defines the focal length, that is, the refractive power of the second lens unit L2. If the upper limit of conditional expression (8) is exceeded and the refractive power is too weak, the zooming action of the second lens unit L2 will be diminished, making it difficult to obtain the desired zoom ratio. If the refractive power is too strong beyond the lower limit of conditional expression (8), more field aberrations occur on the wide-angle side than on the second lens unit L2, and spherical aberration occurs more on the telephoto side.
条件式（９）は第３レンズ群Ｌ３の焦点距離すなわち屈折力を規定する式である。条件式（９）の上限を超えて屈折力が弱すぎると第３レンズ群Ｌ３の変倍作用が薄れ所望の変倍比を得るのが困難になる。また条件式（９）の下限を超えて屈折力が強すぎると第３レンズ群Ｌ３より球面収差、コマ収差、軸上色収差が多く発生してくる。 Conditional expression (9) defines the focal length, that is, the refractive power of the third lens unit L3. If the upper limit of conditional expression (9) is exceeded and the refractive power is too weak, the zooming action of the third lens unit L3 will be diminished, making it difficult to obtain the desired zoom ratio. If the lower limit of conditional expression (9) is exceeded and the refractive power is too strong, more spherical aberration, coma and axial chromatic aberration will occur than in the third lens unit L3.
条件式（１０）は第１レンズ群Ｌ１に含まれる２枚の正レンズの材料の屈折率の差を規定する式である。条件式（１０）の上限を越えて屈折率の差が大きすぎると一方の正レンズの屈折率が大きすぎる場合に相当する。一般に高屈折率な材料はアッベ数の小さい高分散な材料となる。このため上限を越えると高分散すぎて望遠側において軸上色収差、倍率色収差が多く発生してくる。また条件式（１０）の下限を超えて屈折率の差が小さすぎると２枚の正レンズがともに屈折率が低い場合に相当する。第１レンズ群Ｌ１の屈折力をある程度強めようとすると２枚の正レンズで分担しても望遠側において球面収差が多く発生してくる。 Conditional expression (10) is an expression that defines the difference in refractive index between the materials of the two positive lenses included in the first lens unit L1. If the refractive index difference is too large beyond the upper limit of conditional expression (10), this corresponds to the case where the refractive index of one positive lens is too large. In general, a material having a high refractive index is a highly dispersed material having a small Abbe number. For this reason, when the upper limit is exceeded, the dispersion is too high and axial chromatic aberration and lateral chromatic aberration are often generated on the telephoto side. On the other hand, if the difference in refractive index is too small beyond the lower limit of conditional expression (10), this corresponds to the case where both of the two positive lenses have a low refractive index. If the refractive power of the first lens unit L1 is to be increased to some extent, a large amount of spherical aberration occurs on the telephoto side even if it is shared by the two positive lenses.
条件式（１１）は第２レンズ群Ｌ２の像側に凹面を向けた負レンズの像側のレンズ面から物体側に凸面を向けた正レンズの物体側レンズ面までの光軸上の距離を規定する式である。第２レンズ群Ｌ２は負の屈折力のレンズ群が先行するレトロフォーカス型の屈折力配置として広角化と小型化を図っている。この屈折力配置は負レンズの像側に向けた凹面と正レンズの物体側の向けた凸面の配置に強く依存する。ある程度距離を小さくした上で各レンズ面の屈折力を強めに設定すると広角化と小型化が容易となる。条件式（１１）の上限を越えて間隔が大きすぎると第２レンズ群Ｌ２の光軸方向の厚みが増し、第２レンズ群Ｌ２が大型化するので良くない。第２レンズ群Ｌ２が大型化すると第１レンズ群Ｌ１と開口絞りＳＰとの間隔が増大し前玉有効径が大型化してくる。条件式（１１）の下限を超えて間隔が小さすぎると小型化が容易となるが、各レンズ面の屈折力が強くなりすぎて広角側において歪曲収差、像面彎曲、望遠側において球面収差が多く発生してくる。 Conditional expression (11) expresses the distance on the optical axis from the image side lens surface of the negative lens with the concave surface facing the image side of the second lens unit L2 to the object side lens surface of the positive lens with the convex surface facing the object side. It is a formula that prescribes. The second lens unit L2 is designed to have a wide angle and a small size as a retrofocus type refractive power arrangement preceded by a lens unit having a negative refractive power. This refractive power arrangement strongly depends on the arrangement of the concave surface facing the image side of the negative lens and the convex surface facing the object side of the positive lens. If the refracting power of each lens surface is set to be strong after reducing the distance to some extent, widening and miniaturization are facilitated. If the distance is too large beyond the upper limit of conditional expression (11), the thickness of the second lens unit L2 in the optical axis direction is increased, and the second lens unit L2 is enlarged, which is not good. When the second lens unit L2 increases in size, the distance between the first lens unit L1 and the aperture stop SP increases, and the effective diameter of the front lens increases. If the distance is too small beyond the lower limit of conditional expression (11), it is easy to reduce the size. However, the refractive power of each lens surface becomes too strong, and distortion on the wide angle side, curvature of field, and spherical aberration on the telephoto side. Many occur.
条件式（１２）は第２レンズ群Ｌ２の負レンズのうち屈折力の絶対値が最も大きい負レンズＧ２ｎと正レンズＧ２ｐの材料のアッベ数の逆数の差を規定する式である。アッベ数の逆数の差が大きいほど色消しのために必要な各レンズの屈折力は小さくてすむ。条件式（１２）の上限を越えてアッベ数の逆数の差が大きすぎるのは正レンズＧ２ｐの材料が高分散すぎる場合である。一般に高分散材料は部分分散比が大きくなる。上限を越える場合は正レンズＧ２ｐの材料の部分分散比が大きすぎて望遠側において二次スペクトルが増大してくる。また条件式（１２）の下限を超えてアッベ数の逆数の差が小さすぎる場合は色消しのために必要な各レンズの屈折力が大きくなりすぎ、広角側において歪曲収差、像面彎曲、望遠側において球面収差が多く発生してくる。 Conditional expression (12) is an expression defining the difference between the reciprocals of the Abbe numbers of the negative lens G2n and the positive lens G2p having the largest absolute value of refractive power among the negative lenses of the second lens unit L2. The larger the difference between the reciprocals of the Abbe number, the smaller the refractive power of each lens required for achromaticity. The difference between the reciprocals of the Abbe number exceeding the upper limit of the conditional expression (12) is too large when the material of the positive lens G2p is too highly dispersed. Generally, a high dispersion material has a large partial dispersion ratio. When the upper limit is exceeded, the partial dispersion ratio of the material of the positive lens G2p is too large, and the secondary spectrum increases on the telephoto side. If the difference between the reciprocals of the Abbe number is too small beyond the lower limit of conditional expression (12), the refractive power of each lens necessary for achromaticity becomes too large, and distortion, field curvature, and telephoto are wide at the wide angle side. A lot of spherical aberration occurs on the side.
各実施例において、更に好ましくは条件式（６）〜（９）、（１１）、（１２）の数値範囲を次の如く設定するのが良い。 In each embodiment, it is more preferable to set the numerical ranges of conditional expressions (6) to (9), (11), and (12) as follows.
−３．８＜Ｍ３／ｆｗ＜−３．０・・・・・・・・・・・・・（６ａ）
７．４＜ｆ１／ｆｗ＜９．０・・・・・・・・・・・・・・・（７ａ）
１．３＜｜ｆ２｜／ｆｗ＜１．５・・・・・・・・・・・・・（８ａ）
１．８＜ｆ３／ｆｗ＜４．５・・・・・・・・・・・・・・・（９ａ）
０．５６＜ｄ２／ｆｗ＜０．９５・・・・・・・・・・・・（１１ａ）
０．０３０＜（１／ν２ｐ−１／ν２ｎ）＜０．０４５・・（１２ａ）
実施例１、参考例１、参考例２、実施例２、参考例３のズームレンズの特徴について説明する。図１、図５、図７の実施例１、参考例２、実施例２のズームレンズでは、広角端から望遠端のズーム位置へのズーミングに際して、次の如く各レンズ群間隔を変化させている。即ち、第１レンズ群Ｌ１と第２レンズ群Ｌ２との間隔が広がるよう、第２レンズ群Ｌ２と第３レンズ群Ｌ３との間隔が狭まるよう、第３レンズ群Ｌ３と第４レンズ群Ｌ４との間隔が変化するようにしている。更に第４レンズ群Ｌ４と第５レンズ群Ｌ５の間隔が広がるように各レンズ群が移動している。
−3.8 <M3 / fw <−3.0 (6a)
7.4 <f1 / fw <9.0 (7a)
1.3 <| f2 | / fw <1.5 (8a)
1.8 <f3 / fw <4.5 (9a)
0.56 <d2 / fw <0.95 (11a)
0.030 <(1 / ν2p−1 / ν2n) <0.045 (12a)
The features of the zoom lenses of Example 1, Reference Example 1, Reference Example 2, Example 2, and Reference Example 3 will be described. In the zoom lenses of Example 1, Reference Example 2, and Example 2 of FIGS. 1, 5, and 7, the lens group intervals are changed as follows during zooming from the wide-angle end to the telephoto end zoom position. . That is, the third lens group L3 and the fourth lens group L4 are arranged so that the distance between the second lens group L2 and the third lens group L3 is narrowed so that the distance between the first lens group L1 and the second lens group L2 is widened. The interval is changed. Further, each lens group is moved so that the distance between the fourth lens group L4 and the fifth lens group L5 is increased.
図１、図５、図７の実施例１、参考例２、実施例２のズームレンズでは、広角端と比べて望遠端にて、第１レンズ群Ｌ１、第３レンズ群Ｌ３、第４レンズ群Ｌ４は物体側に位置している。また第２レンズ群Ｌ２は像側に凸状の軌跡で、第５レンズ群Ｌ５は物体側に凸状の軌跡を描いて移動している。図１、図５、図７の実施例１、参考例２、実施例２のズームレンズではＦナンバー決定部材ＳＰは、光軸方向に関して、第３レンズ群Ｌ３内に配置している。開口絞りＳＰをこのように配置することにより望遠端における第２レンズ群Ｌ２と第３レンズ群Ｌ３の間隔が詰められるため、ズーミングのための第２レンズ群Ｌ２と第３レンズ群Ｌ３との間隔変化量を十分確保することができる。これにより高ズーム比のズームレンズを達成している。更に図１、図５、図７の実施例１、参考例２、実施例２のズームレンズでは広角端よりも望遠端において第３レンズ群Ｌ３と第４レンズ群Ｌ４との間隔を広げることで更なる変倍作用を得ている。 In the zoom lenses of Example 1, Reference Example 2, and Example 2 of FIGS. 1, 5, and 7, the first lens unit L1, the third lens unit L3, and the fourth lens at the telephoto end compared to the wide-angle end. The group L4 is located on the object side. The second lens unit L2 moves with a convex locus on the image side, and the fifth lens unit L5 moves with a convex locus on the object side. In the zoom lenses of Example 1, Reference Example 2, and Example 2 of FIGS. 1, 5, and 7, the F-number determining member SP is disposed in the third lens unit L3 with respect to the optical axis direction. By disposing the aperture stop SP in this way, the distance between the second lens group L2 and the third lens group L3 at the telephoto end is reduced, so the distance between the second lens group L2 and the third lens group L3 for zooming. A sufficient amount of change can be secured. This achieves a zoom lens with a high zoom ratio. Further, in the zoom lenses of Example 1, Reference Example 2, and Example 2 in FIGS. 1, 5, and 7, the distance between the third lens unit L3 and the fourth lens unit L4 is increased at the telephoto end than at the wide angle end. Further scaling effect is obtained.
図３の参考例１のズームレンズでは、広角端から望遠端のズーム位置へのズーミングに際して、次の如く各レンズ群間隔を変化させている。即ち第１レンズ群Ｌ１と第２レンズ群Ｌ２との間隔が広がるよう、第２レンズ群Ｌ２と第３レンズ群Ｌ３との間隔が狭まるよう、第３レンズ群と第４レンズ群Ｌ４の間隔が広がるように各レンズ群が移動している。図３の参考例１のズームレンズでは、広角端と比べて望遠端にて、第１レンズ群Ｌ１、第３レンズ群Ｌ３は物体側に位置している。また第２レンズ群Ｌ２は像側に凸状の軌跡で、第４レンズ群Ｌ５は物体側に凸状の軌跡を描いて移動している。図３の参考例１のズームレンズではＦナンバー決定部材ＳＰは、光軸方向に関して、第３レンズ群Ｌ３の物体側に配置している。図９の参考例３のズームレンズでは、広角端から望遠端のズーム位置へのズーミングに際して、次の如く各レンズ群間隔を変化させている。即ち、第１レンズ群Ｌ１と第２レンズ群Ｌ２との間隔が広がるよう、第２レンズ群Ｌ２と第３レンズ群Ｌ３との間隔が狭まるよう、第３レンズ群Ｌ３と第４レンズ群Ｌ４の間隔が狭まるようにしている。更に第４レンズ群Ｌ４と第５レンズ群Ｌ５との間隔は広がるように各レンズ群が移動している。 In the zoom lens of Reference Example 1 shown in FIG. 3, when zooming from the wide-angle end to the telephoto end zoom position, the distance between the lens groups is changed as follows. That is, the distance between the third lens group L4 and the fourth lens group L4 is set so that the distance between the second lens group L2 and the third lens group L3 is narrowed so that the distance between the first lens group L1 and the second lens group L2 is widened. Each lens group moves so as to expand. In the zoom lens of Reference Example 1 in FIG. 3, the first lens unit L1 and the third lens unit L3 are located on the object side at the telephoto end compared to the wide-angle end. The second lens unit L2 moves with a convex locus on the image side, and the fourth lens unit L5 moves with a convex locus on the object side. In the zoom lens of Reference Example 1 in FIG. 3, the F-number determining member SP is disposed on the object side of the third lens unit L3 with respect to the optical axis direction. In the zoom lens of Reference Example 3 in FIG. 9, the distance between the lens groups is changed as follows during zooming from the wide-angle end to the telephoto end zoom position. That is, the third lens group L3 and the fourth lens group L4 are arranged so that the distance between the second lens group L2 and the third lens group L3 is narrowed so that the distance between the first lens group L1 and the second lens group L2 is widened. The interval is narrowed. Further, each lens group is moved so that the distance between the fourth lens group L4 and the fifth lens group L5 is increased.
図９の参考例３のズームレンズでは、広角端と比べて望遠端にて、第１レンズ群Ｌ１、第３レンズ群Ｌ３、第４レンズ群Ｌ４は物体側に位置している。また第２レンズ群Ｌ２は像側に凸状の軌跡で、第５レンズ群Ｌ５は物体側に凸状の軌跡を描いて移動している。図９の参考例３のズームレンズではＦナンバー決定部材ＳＰは、光軸方向に関して、第３レンズ群Ｌ３の物体側に配置している。図９の参考例３のズームレンズでは広角端よりも望遠端において第３レンズ群Ｌ３と第４レンズ群Ｌ４との間隔を狭めることで更なる変倍作用を得ている。 In the zoom lens of Reference Example 3 in FIG. 9, the first lens unit L1, the third lens unit L3, and the fourth lens unit L4 are located on the object side at the telephoto end compared to the wide angle end. The second lens unit L2 moves with a convex locus on the image side, and the fifth lens unit L5 moves with a convex locus on the object side. In the zoom lens of Reference Example 3 in FIG. 9, the F-number determining member SP is arranged on the object side of the third lens unit L3 with respect to the optical axis direction. In the zoom lens of Reference Example 3 in FIG. 9, a further zooming effect is obtained by narrowing the distance between the third lens unit L3 and the fourth lens unit L4 at the telephoto end rather than at the wide angle end.
各実施例では以上のような構成とすることで広角端および望遠端においてレンズ全長を短縮しつつ高ズーム比化を図っている。なお各実施例では任意のレンズ群を光軸に対して垂直な方向の成分を持つように移動させて像位置を移動し、手ぶれ補正を行うようにしても良い。 In each embodiment, the above-described configuration achieves a high zoom ratio while shortening the total lens length at the wide-angle end and the telephoto end. In each embodiment, an arbitrary lens group may be moved so as to have a component in a direction perpendicular to the optical axis to move the image position, and camera shake correction may be performed.
次に各レンズ群のレンズ構成について説明する。第１レンズ群Ｌ１は物体側より像側へ順に、負（負の屈折力の）レンズ１１と正（正の屈折力の）レンズ１２で構成された接合レンズ１４、物体側に凸面を向けたメニスカス形状の正レンズで１３構成している。各実施例では小型で高ズーム比のズームレンズを得るために第１レンズ群Ｌ１の屈折力をある程度強めている。このとき第１レンズ群Ｌ１で諸収差が多く発生する。特に望遠側において球面収差が多く発生してくる。各実施例では第１レンズ群Ｌ１の正の屈折力を接合レンズ１４と正レンズ１３で分担しこれら諸収差の発生を低減している。 Next, the lens configuration of each lens group will be described. The first lens unit L1 has, in order from the object side to the image side, a cemented lens 14 including a negative (negative refractive power) lens 11 and a positive (positive refractive power) lens 12, and a convex surface directed toward the object side. There are 13 meniscus positive lenses. In each embodiment, the refractive power of the first lens unit L1 is increased to some extent in order to obtain a compact zoom lens with a high zoom ratio. At this time, many aberrations occur in the first lens unit L1. In particular, a large amount of spherical aberration occurs on the telephoto side. In each embodiment, the positive refractive power of the first lens unit L1 is shared by the cemented lens 14 and the positive lens 13 to reduce the occurrence of these various aberrations.
更に正レンズ１２にアッベ数が８０を越える低分散な材料を用いている。これにより望遠側において軸上色収差と倍率色収差を良好に補正している。なお、正レンズ１２はある程度屈折力を強めることで低分散の効果を高めている。望遠側において球面収差を補正する点では第１レンズ群L１の正レンズを屈折率の高い材料で構成することが好ましい。一般に低分散な材料は屈折率が低いため正レンズ１２を低分散材料とすると屈折率を高くすることができない。よって各実施例のズームレンズでは正レンズ１３に正レンズ１２の材料よりも高い屈折力の材料を用いて望遠側において球面収差の発生を低減している。第１レンズ群Ｌ１を以上の様なレンズ構成とすることで高ズーム比を確保しつつ望遠側において色収差を良好に補正している。 Further, a low dispersion material having an Abbe number exceeding 80 is used for the positive lens 12. As a result, axial chromatic aberration and lateral chromatic aberration are corrected well on the telephoto side. The positive lens 12 enhances the refractive power by increasing the refractive power to some extent. In terms of correcting spherical aberration on the telephoto side, it is preferable that the positive lens of the first lens unit L1 is made of a material having a high refractive index. In general, a low-dispersion material has a low refractive index. Therefore, if the positive lens 12 is a low-dispersion material, the refractive index cannot be increased. Therefore, in the zoom lens of each embodiment, the positive lens 13 is made of a material having a higher refractive power than the material of the positive lens 12 to reduce the occurrence of spherical aberration on the telephoto side. By configuring the first lens unit L1 as described above, chromatic aberration is favorably corrected on the telephoto side while ensuring a high zoom ratio.
第２レンズ群Ｌ２は物体側より像側へ順に、屈折力の絶対値が物体側へ比べ像側のレンズ面が大きく、像側に凹面を向けた負レンズ２１、負レンズ２２、物体側に凸面を向けた正レンズ２３で構成している。各実施例では広角端において広い画角を得ながら第１レンズ群Ｌ１を小型化するために第２レンズ群Ｌ２の屈折力をある程度強めている。このとき第２レンズ群Ｌ２で発生する諸収差、特に広角側において像面彎曲、望遠側において球面収差が多く発生してくる。そこで各実施例では第２レンズ群Ｌ２の負の屈折力を負レンズ２枚で分担しこれらの諸収差の発生を低減している。このようなレンズ構成により広角化を図りながら前玉の小型化と高性能化を図っている。 In the second lens unit L2, in order from the object side to the image side, the absolute value of the refractive power is larger on the image side than on the object side, and the negative lens 21 with the concave surface facing the image side, the negative lens 22, and the object side It is composed of a positive lens 23 having a convex surface. In each embodiment, the refractive power of the second lens unit L2 is increased to some extent in order to reduce the size of the first lens unit L1 while obtaining a wide angle of view at the wide angle end. At this time, various aberrations generated in the second lens unit L2, particularly, field curvature on the wide angle side and spherical aberration on the telephoto side are generated. Therefore, in each embodiment, the negative refractive power of the second lens unit L2 is shared by the two negative lenses to reduce the occurrence of these various aberrations. With such a lens configuration, the front lens is reduced in size and performance while achieving a wider angle.
更に正レンズ２３にアッベ数が１８．０より小さい高分散な材料を用いることで色消しのために必要な第２レンズ群Ｌ２の各レンズの屈折力をなるべく小さく抑えている。これにより第２レンズ群Ｌ２のレンズ枚数を抑え全系の小型化を図っている。また正レンズ２３に高分散な材料を用いることで広角端から望遠端に至る倍率色収差の変動を軽減している。第２レンズ群Ｌ２を以上の様なレンズ構成とすることで第２レンズ群Ｌ２の屈折力を強めながら全系の小型化と色収差の補正を良好に行っている。特に第２レンズ群Ｌ２が小型化されると第１レンズ群Ｌ１と絞りＳＰとの距離が短縮されるため前玉径の小型化が容易になる。第３レンズ群Ｌ３を図１、図３、図５、図７の実施例１、参考例１、参考例２、実施例２では物体側より像側へ順に、物体側に凸面を向けた正レンズ３１、像側に凹面を向けた負レンズ３２、正レンズ３３で構成している。 Further, by using a highly dispersed material having an Abbe number smaller than 18.0 for the positive lens 23, the refractive power of each lens of the second lens unit L2 necessary for achromaticity is kept as small as possible. As a result, the number of lenses in the second lens unit L2 is reduced to reduce the size of the entire system. In addition, the use of a highly dispersed material for the positive lens 23 reduces the variation in lateral chromatic aberration from the wide-angle end to the telephoto end. By making the second lens unit L2 have the above-described lens configuration, the entire system is reduced in size and chromatic aberration is favorably corrected while increasing the refractive power of the second lens unit L2. In particular, when the second lens unit L2 is downsized, the distance between the first lens unit L1 and the stop SP is shortened, so that the front lens diameter can be easily downsized. In Example 1, Reference Example 1, Reference Example 2, and Example 2 in FIGS. 1, 3, 5, and 7, the third lens unit L3 is a positive lens with a convex surface facing the object side in order from the object side. The lens 31 includes a negative lens 32 having a concave surface facing the image side, and a positive lens 33.
各実施例では第３レンズ群Ｌ３の変倍作用を強めるとともに広角端においてレンズ全長を短縮するために第３レンズ群Ｌ３の屈折力をある程度強めている。このとき第３レンズ群Ｌ３で発生する諸収差、特にズーム全域において球面収差、コマ収差、軸上色収差が多く発生してくる。そこで各実施例では第３レンズ群Ｌ３の正の屈折力を２つの正レンズで分担することにより、これら諸収差の発生を低減している。各実施例では２枚の正レンズと１枚の負レンズにて第３レンズ群Ｌ３を構成している。 In each embodiment, the refractive power of the third lens unit L3 is increased to some extent in order to increase the zooming action of the third lens unit L3 and to shorten the total lens length at the wide angle end. At this time, various aberrations occurring in the third lens unit L3, particularly spherical aberration, coma aberration, and axial chromatic aberration, are often generated over the entire zoom range. Therefore, in each embodiment, the positive refractive power of the third lens unit L3 is shared by the two positive lenses, thereby reducing the occurrence of these various aberrations. In each embodiment, the third lens unit L3 includes two positive lenses and one negative lens.
第３レンズ群Ｌ３を図９の参考例３では物体側より像側へ順に、物体側に凸面を向けた正レンズ３１、像側に凹面を向けた負レンズ３２で構成している。図９の参考例３は第４レンズ群Ｌ４を正の屈折力として第３レンズ群Ｌ３の正の屈折力を弱めている。これにより図９の参考例３では第３レンズ群Ｌ３に含まれる正レンズは１枚としている。第４レンズ群Ｌ４を図１、図５、図７の実施例１、参考例２、実施例２では負レンズ４１のみで構成している。各実施例では少ない構成レンズ枚数で第４レンズ群Ｌ４を構成することで薄型化、軽量化を図っている。第４レンズ群Ｌ４を図３の参考例１では正レンズ４１１と負レンズ４１２とを接合した接合レンズ４１３で構成している。これによって、屈折力を強めたときでもズーミングの際の色収差の変動を軽減している。第４レンズ群Ｌ４を図９の参考例３では正レンズ４２１のみで構成している。各実施例では少ない構成レンズ枚数で第４レンズ群を構成することで薄型化、軽量化を図っている。 In Reference Example 3 of FIG. 9, the third lens unit L3 includes, in order from the object side to the image side, a positive lens 31 having a convex surface facing the object side and a negative lens 32 having a concave surface facing the image side. In Reference Example 3 of FIG. 9, the fourth lens unit L4 is used as a positive refractive power, and the positive refractive power of the third lens unit L3 is weakened. Accordingly, in Reference Example 3 in FIG. 9, the number of positive lenses included in the third lens unit L3 is one. The fourth lens unit L4 includes only the negative lens 41 in the first embodiment, the reference example 2, and the second embodiment in FIGS. In each embodiment, the fourth lens unit L4 is configured with a small number of constituent lenses to reduce the thickness and weight. In the first reference example of FIG. 3, the fourth lens unit L4 includes a cemented lens 413 in which a positive lens 411 and a negative lens 412 are cemented. As a result, even when the refractive power is strengthened, fluctuations in chromatic aberration during zooming are reduced. The fourth lens unit L4 includes only the positive lens 421 in Reference Example 3 of FIG. In each embodiment, the fourth lens group is configured with a small number of constituent lenses to achieve a reduction in thickness and weight.
第５レンズ群Ｌ５を図１、図５、図７、図９の実施例１、参考例２、実施例２、参考例３では物体側より像側へ順に、正レンズ５１、負レンズ５２で構成された接合レンズ５３で構成している。接合レンズとすることで各レンズ群の屈折力をある程度強めた場合でも変倍全域にて倍率色収差の発生を良好に抑えている。 In Example 1, Reference Example 2, Example 2, and Reference Example 3 of FIGS. 1, 5, 7, and 9, the fifth lens unit L5 is composed of a positive lens 51 and a negative lens 52 in order from the object side to the image side. The cemented lens 53 is configured. Even if the refractive power of each lens group is increased to some extent by using a cemented lens, the occurrence of lateral chromatic aberration is satisfactorily suppressed over the entire zooming range.
次に実施例１、参考例１、参考例２、実施例２、参考例３に対応する数値実施例１乃至５を示す。各数値実施例において、ｉは物体側からの光学面の順序を示す。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である。ｄｉは物体側より順に第ｉ番目のレンズ厚及び空気間隔である。ｎｄｉとνｄｉは各々物体側より順に第ｉ番目の材料のガラスのｄ線に対する屈折率、アッベ数である。数値実施例において最後の２つの面は、フィルター、フェースプレート等の光学ブロックの面である。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、Kを円錐定数、A4，A6，A8，A10を各々非球面係数としたとき Next, Numerical Examples 1 to 5 corresponding to Example 1, Reference Example 1, Reference Example 2, Example 2, and Reference Example 3 are shown. In each numerical example, i indicates the order of the optical surfaces from the object side. 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 in order from the object side. ndi and νdi are respectively the refractive index and Abbe number for the d-line of the glass of the i-th material in order from the object side. In the numerical example, the last two surfaces are surfaces of an optical block such as a filter and a face plate. The aspherical shape is the X axis in the optical axis direction, the H axis in the direction perpendicular to the optical axis, the light traveling direction is positive, R is the paraxial radius of curvature, K is the conic constant, and A4, A6, A8, and A10 are aspherical surfaces. When using coefficients
なる式で表している。また、［e+X］は［×10＋ｘ］を意味し、［e-X］は［×10−ｘ］を意味している。画角は半画角（度）を示している。ＢＦはレンズ最終面から近軸像面までの距離（バックフォーカス）を空気換算したものである。レンズ全長はレンズ最前面からレンズ最終面までの距離にバックフォーカスＢＦを加えたものである。非球面は面番号の後に*を付加して示す。前述の各条件式と数値実施例における諸数値の関係を表１に示す。 It is expressed by the following formula. [E + X] means [× 10 + x ], and [eX] means [× 10 −x ]. The angle of view indicates a half angle of view (degree). BF is the air-converted distance (back focus) from the final lens surface to the paraxial image plane. The total lens length is obtained by adding the back focus BF to the distance from the lens front surface to the lens final surface. An aspherical surface is indicated by adding * after the surface number. Table 1 shows the relationship between the above-described conditional expressions and various numerical values in the numerical examples.
［数値実施例１］
単位 mm
面データ
面番号 r d nd νd
1 47.198 0.90 1.84666 23.9
2 28.488 2.50 1.49700 81.5
3 539.546 0.20
4 27.858 1.95 1.69680 55.5
5 130.634 (可変)
6 -142.993 1.03 1.85135 40.1
7*
5.724 2.27
8 -32.718 0.60 1.80400 46.6
9 20.754 0.20
10 10.630 1.40 1.94595 18.0
11 41.156 (可変)
12* 7.790 1.40 1.58313 59.4
13* -42.498 0.92
14(絞り) ∞ 1.48
15 14.621 0.60 1.94595 18.0
16 7.752 0.51
17 38.232 1.45 1.60311 60.6
18 -10.112 (可変)
19 -22.588 0.50 1.48749 70.2
20 23.874 (可変)
21 15.072 2.00 1.69680 55.5
22 -42.895 0.60 1.72825 28.5
23 240.459 (可変)
24 ∞ 0.80 1.51633 64.1
25 ∞ 0.90
像面 ∞
非球面データ
第7面
K =-1.12918e+000 A 4= 7.09263e-004 A 6= 1.64697e-005 A 8=-3.81294e-007 A10= 1.79401e-008
第12面
K =-1.22101e+000 A 4= 4.95648e-005 A 6= 7.55352e-006 A 8= 3.03893e-006 A10=-1.83896e-007
第13面
K =-1.36363e+002 A 4= 9.00236e-007 A 6= 2.00697e-005 A 8= 2.20070e-006 A10=-1.36759e-007
各種データ
ズーム比 13.32
広角 中間 望遠
焦点距離 5.12 17.53 68.25
Fナンバー 3.21 4.62 6.08
画角 33.04 12.46 3.25
像高 3.33 3.88 3.88
レンズ全長 48.61 56.13 75.70
BF 6.95 13.90 7.26
d 5 0.95 11.54 25.33
d11 15.79 4.21 0.71
d18 1.90 2.57 3.04
d20 2.51 3.39 18.85
d23 5.52 12.48 5.84
ズームレンズ群データ
群 始面 焦点距離
1 1 41.07
2 6 -6.74
3 12 10.27
4 19 -23.73
5 21 23.41
6 24 ∞
[Numerical Example 1]
Unit mm
Surface data surface number rd nd νd
1 47.198 0.90 1.84666 23.9
2 28.488 2.50 1.49700 81.5
3 539.546 0.20
4 27.858 1.95 1.69680 55.5
5 130.634 (variable)
6 -142.993 1.03 1.85135 40.1
7 *
5.724 2.27
8 -32.718 0.60 1.80 400 46.6
9 20.754 0.20
10 10.630 1.40 1.94595 18.0
11 41.156 (variable)
12 * 7.790 1.40 1.58313 59.4
13 * -42.498 0.92
14 (Aperture) ∞ 1.48
15 14.621 0.60 1.94595 18.0
16 7.752 0.51
17 38.232 1.45 1.60311 60.6
18 -10.112 (variable)
19 -22.588 0.50 1.48749 70.2
20 23.874 (variable)
21 15.072 2.00 1.69680 55.5
22 -42.895 0.60 1.72825 28.5
23 240.459 (variable)
24 ∞ 0.80 1.51633 64.1
25 ∞ 0.90
Image plane ∞
Aspheric data 7th surface
K = -1.12918e + 000 A 4 = 7.09263e-004 A 6 = 1.64697e-005 A 8 = -3.81294e-007 A10 = 1.79401e-008
12th page
K = -1.22101e + 000 A 4 = 4.95648e-005 A 6 = 7.55352e-006 A 8 = 3.03893e-006 A10 = -1.83896e-007
Side 13
K = -1.36363e + 002 A 4 = 9.00236e-007 A 6 = 2.00697e-005 A 8 = 2.20070e-006 A10 = -1.36759e-007
Various data Zoom ratio 13.32
Wide angle Medium telephoto focal length 5.12 17.53 68.25
F number 3.21 4.62 6.08
Angle of view 33.04 12.46 3.25
Image height 3.33 3.88 3.88
Total lens length 48.61 56.13 75.70
BF 6.95 13.90 7.26
d 5 0.95 11.54 25.33
d11 15.79 4.21 0.71
d18 1.90 2.57 3.04
d20 2.51 3.39 18.85
d23 5.52 12.48 5.84
Zoom lens group data group Start surface Focal length
1 1 41.07
2 6 -6.74
3 12 10.27
4 19 -23.73
5 21 23.41
6 24 ∞
［数値実施例２］
単位 mm
面データ
面番号 r d nd νd
1 40.508 1.10 1.84666 23.9
2 26.505 2.85 1.49700 81.5
3 117.405 0.20
4 28.036 2.30 1.69680 55.5
5 115.344 (可変)
6 496.060 0.80 1.83481 42.7
7 6.978 3.11
8 -19.492 0.65 1.69680 55.5
9 27.002 0.95
10 17.132 1.30 1.94595 18.0
11 86.758 (可変)
12(絞り) ∞ 1.10
13* 6.129 2.60 1.55332 71.7
14* -19.640 1.44
15 30.262 0.70 1.80610 33.3
16 5.458 0.36
17
7.690 2.20 1.48749 70.2
18 43.575 (可変)
19 16.720 2.50 1.65844 50.9
20 -30.217 0.80 1.84666 23.9
21 -745.365 (可変)
22 ∞ 0.80 1.51633 64.1
23 ∞ 0.23
像面 ∞
非球面データ
第13面
K = 8.82654e-002 A 4=-3.72261e-004 A 6=-6.26683e-006 A 8= 7.60386e-007 A10=-1.17611e-008
第14面
K =-1.54914e+001 A 4= 1.11231e-004 A 6= 9.16897e-006 A 8= 4.07239e-007 A10= 2.20754e-008
各種データ
ズーム比 11.41
広角 中間 望遠
焦点距離 5.13 27.84 58.49
Fナンバー 3.43 4.75 5.72
画角 33.64 7.92 3.79
像高 3.41 3.88 3.88
レンズ全長 58.03 68.24 80.67
BF 5.83 14.87 8.72
d 5 0.85 19.50 26.21
d11 20.70 3.30 1.55
d18 5.69 5.62 19.24
d21 4.90 13.94 7.79
ズームレンズ群データ
群 始面 焦点距離
1 1 44.91
2 6 -7.55
3 12 13.79
4 19 28.92
5 22 ∞
[Numerical Example 2]
Unit mm
Surface data surface number rd nd νd
1 40.508 1.10 1.84666 23.9
2 26.505 2.85 1.49700 81.5
3 117.405 0.20
4 28.036 2.30 1.69680 55.5
5 115.344 (variable)
6 496.060 0.80 1.83481 42.7
7 6.978 3.11
8 -19.492 0.65 1.69680 55.5
9 27.002 0.95
10 17.132 1.30 1.94595 18.0
11 86.758 (variable)
12 (Aperture) ∞ 1.10
13 * 6.129 2.60 1.55332 71.7
14 * -19.640 1.44
15 30.262 0.70 1.80610 33.3
16 5.458 0.36
17
7.690 2.20 1.48749 70.2
18 43.575 (variable)
19 16.720 2.50 1.65844 50.9
20 -30.217 0.80 1.84666 23.9
21 -745.365 (variable)
22 ∞ 0.80 1.51633 64.1
23 ∞ 0.23
Image plane ∞
Aspherical data 13th surface
K = 8.82654e-002 A 4 = -3.72261e-004 A 6 = -6.26683e-006 A 8 = 7.60386e-007 A10 = -1.17611e-008
14th page
K = -1.54914e + 001 A 4 = 1.11231e-004 A 6 = 9.16897e-006 A 8 = 4.07239e-007 A10 = 2.20754e-008
Various data Zoom ratio 11.41
Wide angle Medium Telephoto focal length 5.13 27.84 58.49
F number 3.43 4.75 5.72
Angle of view 33.64 7.92 3.79
Image height 3.41 3.88 3.88
Total lens length 58.03 68.24 80.67
BF 5.83 14.87 8.72
d 5 0.85 19.50 26.21
d11 20.70 3.30 1.55
d18 5.69 5.62 19.24
d21 4.90 13.94 7.79
Zoom lens group data group Start surface Focal length
1 1 44.91
2 6 -7.55
3 12 13.79
4 19 28.92
5 22 ∞
［数値実施例３］
単位 mm
面データ
面番号 r d nd νd
1 46.369 0.90 1.84666 23.9
2 27.571 2.50 1.43875 94.9
3 559.981 0.20
4 30.024 1.95 1.77250 49.6
5 181.678 (可変)
6 1208.784 1.03 1.85135 40.1
7* 5.930 2.52
8 -37.450 0.60 1.80400 46.6
9 24.691 0.20
10 10.171 1.00 2.15000 15.0
11 18.413 (可変)
12* 7.811 1.40 1.58313 59.4
13* -47.243 0.92
14(絞り) ∞ 1.48
15 14.957 0.60 1.94595 18.0
16 7.736 0.51
17 30.949 1.45 1.60311 60.6
18 -9.935 (可変)
19 -22.814 0.50 1.48749 70.2
20 27.914 (可変)
21 14.636 2.00 1.69680 55.5
22 -213.155 0.60 1.72825 28.5
23 80.738 (可変)
24 ∞ 0.80 1.51633 64.1
25 ∞ 0.90
像面 ∞
非球面データ
第7面
K =-1.06717e+000 A 4= 6.59232e-004 A 6= 1.99244e-005 A 8=-6.18757e-007 A10= 2.60294e-008
第12面
K =-1.58528e+000 A 4= 6.04929e-005 A 6= 3.14605e-006 A 8= 4.09286e-006 A10=-3.60415e-007
第13面
K =-1.45184e+002 A 4=-4.52161e-005 A 6= 1.30432e-005 A 8= 3.34384e-006 A10=-3.15471e-007
各種データ
ズーム比 13.82
広角 中間 望遠
焦点距離 4.96 16.36 68.60
Fナンバー 3.36 4.65 6.09
画角 33.88 13.33 3.23
像高 3.33 3.88 3.88
レンズ全長 48.67 55.53 74.48
BF 6.49 13.36 7.17
d 5 0.80 10.94 25.72
d11 16.55 4.87 0.47
d18 1.90 1.84 2.50
d20 2.57 4.15 18.26
d23 5.06 11.93 5.75
ズームレンズ群データ
群 始面 焦点距離
1 1 41.50
2 6 -6.86
3 12 10.21
4 19 -25.67
5 21 25.57
6 24 ∞
[Numerical Example 3]
Unit mm
Surface data surface number rd nd νd
1 46.369 0.90 1.84666 23.9
2 27.571 2.50 1.43875 94.9
3 559.981 0.20
4 30.024 1.95 1.77250 49.6
5 181.678 (variable)
6 1208.784 1.03 1.85 135 40.1
7 * 5.930 2.52
8 -37.450 0.60 1.80 400 46.6
9 24.691 0.20
10 10.171 1.00 2.15000 15.0
11 18.413 (variable)
12 * 7.811 1.40 1.58313 59.4
13 * -47.243 0.92
14 (Aperture) ∞ 1.48
15 14.957 0.60 1.94595 18.0
16 7.736 0.51
17 30.949 1.45 1.60311 60.6
18 -9.935 (variable)
19 -22.814 0.50 1.48749 70.2
20 27.914 (variable)
21 14.636 2.00 1.69680 55.5
22 -213.155 0.60 1.72825 28.5
23 80.738 (variable)
24 ∞ 0.80 1.51633 64.1
25 ∞ 0.90
Image plane ∞
Aspheric data 7th surface
K = -1.06717e + 000 A 4 = 6.59232e-004 A 6 = 1.99244e-005 A 8 = -6.18757e-007 A10 = 2.60294e-008
12th page
K = -1.58528e + 000 A 4 = 6.04929e-005 A 6 = 3.14605e-006 A 8 = 4.09286e-006 A10 = -3.60415e-007
Side 13
K = -1.45184e + 002 A 4 = -4.52161e-005 A 6 = 1.30432e-005 A 8 = 3.34384e-006 A10 = -3.15471e-007
Various data Zoom ratio 13.82
Wide angle Medium Telephoto focal length 4.96 16.36 68.60
F number 3.36 4.65 6.09
Angle of view 33.88 13.33 3.23
Image height 3.33 3.88 3.88
Total lens length 48.67 55.53 74.48
BF 6.49 13.36 7.17
d 5 0.80 10.94 25.72
d11 16.55 4.87 0.47
d18 1.90 1.84 2.50
d20 2.57 4.15 18.26
d23 5.06 11.93 5.75
Zoom lens group data group Start surface Focal length
1 1 41.50
2 6 -6.86
3 12 10.21
4 19 -25.67
5 21 25.57
6 24 ∞
［数値実施例４］
単位 mm
面データ
面番号 r d nd νd
1 40.829 0.90 1.84666 23.9
2 28.443 2.80 1.45600 90.3
3 -111.369 0.20
4 28.907 1.60 1.60311 60.6
5 74.324 (可変)
6 -62.226 1.03 1.85135 40.1
7* 6.063 2.28
8 -23.222 0.60 1.80400 46.6
9 28.259 0.20
10 12.482 1.40 2.14352 17.8
11 41.723 (可変)
12* 7.730 1.40 1.58313 59.4
13* -44.307 0.92
14(絞り) ∞ 1.48
15 14.928 0.60 1.94595 18.0
16 7.828 0.51
17 44.931 1.45 1.60311 60.6
18 -10.044 (可変)
19 -20.840 0.50 1.48749 70.2
20 39.734 (可変)
21 15.540 2.00 1.69680 55.5
22 -31.360 0.60 1.72825 28.5
23 -2306.962 (可変)
24 ∞ 0.80 1.51633 64.1
25 ∞ 0.90
像面 ∞
非球面データ
第7面
K =-8.76488e-001 A 4= 4.28897e-004 A 6= 1.21461e-005 A 8=-2.23456e-007 A10= 7.87605e-009
第12面
K =-1.39680e+000 A 4= 2.06320e-004 A 6= 1.68052e-005 A 8= 1.98340e-006 A10=-1.05023e-007
第13面
K =-1.22659e+002 A 4= 1.72540e-004 A 6= 2.21046e-005 A 8= 2.00595e-006 A10=-9.89895e-008
各種データ
ズーム比 13.54
広角 中間 望遠
焦点距離 5.07 14.88 68.60
Fナンバー 3.37 4.32 6.09
画角 33.33 14.60 3.23
像高 3.33 3.88 3.88
レンズ全長 49.91 56.87 77.21
BF 5.73 12.88 7.79
d 5 1.20 10.84 25.80
d11 16.27 5.10 0.28
d18 1.90 1.12 3.26
d20 4.34 6.46 19.60
d23 4.30 11.46 6.36
ズームレンズ群データ
群 始面 焦点距離
1 1 42.00
2 6 -6.67
3 12 10.41
4 19 -27.97
5 21 22.63
6 24 ∞
[Numerical Example 4]
Unit mm
Surface data surface number rd nd νd
1 40.829 0.90 1.84666 23.9
2 28.443 2.80 1.45600 90.3
3 -111.369 0.20
4 28.907 1.60 1.60311 60.6
5 74.324 (variable)
6 -62.226 1.03 1.85135 40.1
7 * 6.063 2.28
8 -23.222 0.60 1.80 400 46.6
9 28.259 0.20
10 12.482 1.40 2.14352 17.8
11 41.723 (variable)
12 * 7.730 1.40 1.58313 59.4
13 * -44.307 0.92
14 (Aperture) ∞ 1.48
15 14.928 0.60 1.94595 18.0
16 7.828 0.51
17 44.931 1.45 1.60311 60.6
18 -10.044 (variable)
19 -20.840 0.50 1.48749 70.2
20 39.734 (variable)
21 15.540 2.00 1.69680 55.5
22 -31.360 0.60 1.72825 28.5
23 -2306.962 (variable)
24 ∞ 0.80 1.51633 64.1
25 ∞ 0.90
Image plane ∞
Aspheric data 7th surface
K = -8.76488e-001 A 4 = 4.28897e-004 A 6 = 1.21461e-005 A 8 = -2.23456e-007 A10 = 7.87605e-009
12th page
K = -1.39680e + 000 A 4 = 2.06320e-004 A 6 = 1.68052e-005 A 8 = 1.98340e-006 A10 = -1.05023e-007
Side 13
K = -1.22659e + 002 A 4 = 1.72540e-004 A 6 = 2.21046e-005 A 8 = 2.00595e-006 A10 = -9.89895e-008
Various data Zoom ratio 13.54
Wide angle Medium Telephoto focal length 5.07 14.88 68.60
F number 3.37 4.32 6.09
Angle of view 33.33 14.60 3.23
Image height 3.33 3.88 3.88
Total lens length 49.91 56.87 77.21
BF 5.73 12.88 7.79
d 5 1.20 10.84 25.80
d11 16.27 5.10 0.28
d18 1.90 1.12 3.26
d20 4.34 6.46 19.60
d23 4.30 11.46 6.36
Zoom lens group data group Start surface Focal length
1 1 42.00
2 6 -6.67
3 12 10.41
4 19 -27.97
5 21 22.63
6 24 ∞
［数値実施例５］
単位 mm
面データ
面番号 r d nd νd
1 41.069 1.10 1.84666 23.9
2 26.300 2.85 1.49700 81.5
3 121.593 0.20
4 26.171 2.30 1.69680 55.5
5 94.129 (可変)
6 110.635 0.80 1.83481 42.7
7 6.355 3.11
8 -15.251 0.65 1.69680 55.5
9 65.380 0.95
10 17.018 1.30 2.00000 16.0
11 53.947 (可変)
12(絞り) ∞ 1.10
13* 6.428 2.60 1.55332 71.7
14* -16.276 1.44
15 43.996 0.70 1.80610 33.3
16 6.230 (可変)
17 11.376 2.20 1.48749 70.2
18 -380.889 (可変)
19 19.187 2.50 1.65844 50.9
20 -19.742 0.80 1.84666 23.9
21 -109.516 (可変)
22 ∞ 0.80 1.51633 64.1
23 ∞ 0.40
像面 ∞
非球面データ
第13面
K =-7.75765e-002 A 4=-3.85283e-004 A 6= 5.74360e-006 A 8=-6.92005e-007 A10= 8.51546e-008
第14面
K =-9.64194e+000 A 4=-2.31393e-005 A 6= 1.79539e-005 A 8=-9.53438e-007 A10= 1.11464e-007
各種データ
ズーム比 12.27
広角 中間 望遠
焦点距離 5.13 27.56 63.00
Fナンバー 3.50 4.63 5.97
画角 33.59 8.00 3.52
像高 3.41 3.88 3.88
レンズ全長 60.48 70.69 83.12
BF 6.14 15.43 8.28
d 5 0.85 19.50 26.21
d11 20.70 3.30 1.55
d16 2.50 1.50 0.50
d18 5.69 6.37 21.98
d21 5.21 14.50 7.36
ズームレンズ群データ
群 始面 焦点距離
1 1 44.45
2 6 -7.29
3 12 22.27
4 17 22.70
5 19 30.75
6 22 ∞
[Numerical Example 5]
Unit mm
Surface data surface number rd nd νd
1 41.069 1.10 1.84666 23.9
2 26.300 2.85 1.49700 81.5
3 121.593 0.20
4 26.171 2.30 1.69680 55.5
5 94.129 (variable)
6 110.635 0.80 1.83481 42.7
7 6.355 3.11
8 -15.251 0.65 1.69680 55.5
9 65.380 0.95
10 17.018 1.30 2.00000 16.0
11 53.947 (variable)
12 (Aperture) ∞ 1.10
13 * 6.428 2.60 1.55332 71.7
14 * -16.276 1.44
15 43.996 0.70 1.80610 33.3
16 6.230 (variable)
17 11.376 2.20 1.48749 70.2
18 -380.889 (variable)
19 19.187 2.50 1.65844 50.9
20 -19.742 0.80 1.84666 23.9
21 -109.516 (variable)
22 ∞ 0.80 1.51633 64.1
23 ∞ 0.40
Image plane ∞
Aspherical data 13th surface
K = -7.75765e-002 A 4 = -3.85283e-004 A 6 = 5.74360e-006 A 8 = -6.92005e-007 A10 = 8.51546e-008
14th page
K = -9.64194e + 000 A 4 = -2.31393e-005 A 6 = 1.79539e-005 A 8 = -9.53438e-007 A10 = 1.11464e-007
Various data Zoom ratio 12.27
Wide angle Medium Telephoto focal length 5.13 27.56 63.00
F number 3.50 4.63 5.97
Angle of view 33.59 8.00 3.52
Image height 3.41 3.88 3.88
Total lens length 60.48 70.69 83.12
BF 6.14 15.43 8.28
d 5 0.85 19.50 26.21
d11 20.70 3.30 1.55
d16 2.50 1.50 0.50
d18 5.69 6.37 21.98
d21 5.21 14.50 7.36
Zoom lens group data group Start surface Focal length
1 1 44.45
2 6 -7.29
3 12 22.27
4 17 22.70
5 19 30.75
6 22 ∞
次に各実施例に示したようなズームレンズを撮影光学系として用いたデジタルスチルカメラの実施形態を図１１を用いて説明する。図１１において、２０はカメラ本体、２１は実施例１、参考例１、参考例２、実施例２、参考例３で説明したいずれかのズームレンズによって構成された撮影光学系である。２２はカメラ本体に内蔵され、撮影光学系２１によって形成された被写体像を受光するＣＣＤセンサやＣＭＯＳセンサ等の固体撮像素子（光電変換素子）である。２３は固体撮像素子２２によって光電変換された被写体像に対応する情報を記録するメモリである。２４は液晶ディスプレイパネル等によって構成され、固体撮像素子２２上に形成された被写体像を観察するためのファインダである。このように本発明のズームレンズをデジタルスチルカメラ等の撮像装置に適用することにより、小型で高い光学性能を有する撮像装置が実現できる。 Next, an embodiment of a digital still camera using a zoom lens as shown in each embodiment as a photographing optical system will be described with reference to FIG. In FIG. 11, reference numeral 20 denotes a camera body, and reference numeral 21 denotes a photographing optical system constituted by any of the zoom lenses described in the first embodiment, the first reference example, the second reference example, the second embodiment, and the third reference example . Reference numeral 22 denotes a solid-state imaging device (photoelectric conversion device) such as a CCD sensor or a CMOS sensor that receives a subject image formed by the photographing optical system 21 and is built in the camera body. A memory 23 records information corresponding to a subject image photoelectrically converted by the solid-state imaging device 22. Reference numeral 24 denotes a finder for observing a subject image formed on the solid-state image sensor 22, which includes a liquid crystal display panel or the like. In this way, by applying the zoom lens of the present invention to an imaging apparatus such as a digital still camera, a compact imaging apparatus having high optical performance can be realized.
Ｌ１は第１レンズ群、Ｌ２は第２レンズ群、Ｌ３は第３レンズ群、Ｌ４は第４レンズ群、Ｌ５は第５レンズ群、Ｌｒは後群、ｄはｄ線、ｇはｇ線、ΔＭはメリディオナル像面、ΔＳはサジタル像面、ＳＰは絞り、ＧはＣＣＤのフォースプレートやローパスフィルター等のガラスブロック、ωは半画角、ｆｎｏはＦナンバー L1 is the first lens group, L2 is the second lens group, L3 is the third lens group, L4 is the fourth lens group, L5 is the fifth lens group, Lr is the rear group, d is the d-line, g is the g-line, ΔM is a meridional image plane, ΔS is a sagittal image plane, SP is an aperture, G is a glass block such as a CCD force plate or low-pass filter, ω is a half field angle, and fno is an F number.
Claims (9)
広角端に対して望遠端において前記第１レンズ群と前記第２レンズ群の間隔が増大し、前記第２レンズ群と前記第３レンズ群の間隔が減少し、前記第３レンズ群と前記第４レンズ群の間隔が変化し、前記第４レンズ群と前記第５レンズ群の間隔が変化するズームレンズであって、
前記第１レンズ群は正レンズと負レンズを含み、前記第１レンズ群に含まれる正レンズは２つであり、前記第２レンズ群は負レンズ、正レンズを有し、前記第１レンズ群を構成する正レンズのうち材料のアッベ数が最も大きい正レンズの材料のアッベ数をν１ｐ、前記第２レンズ群の１つの正レンズの材料の屈折率とアッベ数を各々Ｎ２ｐ、ν２ｐ、前記第１レンズ群の焦点距離をｆ１、前記第１レンズ群を構成する正レンズのうち材料のアッベ数が最も大きい正レンズの焦点距離をｆ１ｐ、前記第１レンズ群を構成する２つの正レンズの材料の屈折率の差をΔＮ１ｐとするとき、
８０．０＜ν１ｐ
１．０＜ｆ１ｐ／ｆ１＜１．６
ν２ｐ≦１８．０
１．９０＜Ｎ２ｐ
０．１０３＜ΔＮ１ｐ≦０．２００
なる条件を満足することを特徴とするズームレンズ。 In order from the object side to the image side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, a third lens group having a positive refractive power, a fourth lens group having a negative refractive power, and a positive lens Consists of a fifth lens group of refractive power,
The distance between the first lens group and the second lens group is increased at the telephoto end with respect to the wide-angle end, the distance between the second lens group and the third lens group is decreased, and the third lens group and the third lens group are reduced. A zoom lens in which an interval between four lens groups is changed and an interval between the fourth lens group and the fifth lens group is changed;
The first lens group includes a positive lens and a negative lens, the positive lens included in the first lens group is two, the second lens group includes a negative lens and a positive lens, and the first lens group Of the positive lens having the largest Abbe number of the material among the positive lenses constituting ν1p, the refractive index and Abbe number of the material of one positive lens of the second lens group are N2p and ν2p, respectively. The focal length of one lens group is f1, the focal length of the positive lens having the largest Abbe number of the material among the positive lenses constituting the first lens group is f1p, and the materials of the two positive lenses constituting the first lens group When the difference in refractive index is ΔN1p,
80.0 <ν1p
1.0 <f1p / f1 <1.6
ν2p ≦ 18.0
1.90 <N2p
0.103 <ΔN1p ≦ 0. 200
A zoom lens characterized by satisfying the following conditions:
−６．５＜Ｍ１／ｆｗ＜−４．０
なる条件式を満足することを特徴とする請求項１に記載のズームレンズ。 When the movement amount of the first lens unit in zooming from the wide-angle end to the telephoto end is M1, and the focal length of the entire system at the wide-angle end is fw,
−6.5 <M1 / fw <−4.0
The zoom lens according to claim 1, wherein the following conditional expression is satisfied.
−４．０＜Ｍ３／ｆｗ＜−２．７
なる条件を満足することを特徴とする請求項１または２に記載のズームレンズ。 When the amount of movement of the third lens group during zooming from the wide-angle end to the telephoto end is M3, and the focal length of the entire system at the wide-angle end is fw,
−4.0 <M3 / fw <−2.7
The zoom lens according to claim 1, wherein the following condition is satisfied.
７．０＜ｆ１／ｆｗ＜１０．０
なる条件を満足することを特徴とする請求項１乃至３のいずれか１項に記載のズームレンズ。 When the focal length of the entire system at the wide angle end is fw
7.0 <f1 / fw <10.0
The zoom lens according to claim 1, wherein the following condition is satisfied.
なる条件を満足することを特徴とする請求項１乃至４のいずれか１項に記載のズームレンズ。 When the focal length of the second lens group is f2 and the focal length of the entire system at the wide angle end is fw, 1.2 <| f2 | / fw <1.6.
The zoom lens according to claim 1, wherein the following condition is satisfied.
なる条件を満足することを特徴とする請求項１乃至５のいずれか１項に記載のズームレンズ。 When the focal length of the third lens unit is f3 and the focal length of the entire system at the wide angle end is fw, 1.7 <f3 / fw <4.6.
The zoom lens according to claim 1, wherein the following condition is satisfied.
０．５２＜ｄ２／ｆｗ＜１．００
なる条件を満足することを特徴とする請求項１乃至６のいずれか１項に記載のズームレンズ。 In the second lens group, in order from the object side to the image side, the absolute value of the refractive power is larger on the image side than on the object side, and a negative lens G2n having a concave surface on the image side and a convex surface on the object side. A distance d on the optical axis from the image-side lens surface of the negative lens G2n to the object-side lens surface of the positive lens G2p, d2, and the focal length of the entire system at the wide angle end fw And when
0.52 <d2 / fw <1.00
The zoom lens according to claim 1, wherein the following condition is satisfied.
０．０２９＜（１／ν２ｐ−１／ν２ｎ）＜０．０５０
なる条件を満足することを特徴とする請求項１乃至７のいずれか１項に記載のズームレンズ。 When the Abbe number of the negative lens material having the largest absolute value of refractive power among the lenses constituting the second lens group is ν2n,
0.029 <(1 / ν2p−1 / ν2n) <0.05
The zoom lens according to claim 1, wherein the following condition is satisfied.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2014089084A JP5726350B2 (en) | 2014-04-23 | 2014-04-23 | Zoom lens and imaging apparatus having the same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2014089084A JP5726350B2 (en) | 2014-04-23 | 2014-04-23 | Zoom lens and imaging apparatus having the same |
Related Parent Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2009294302A Division JP5538873B2 (en) | 2009-12-25 | 2009-12-25 | Zoom lens and imaging apparatus having the same |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2014134824A JP2014134824A (en) | 2014-07-24 |
| JP5726350B2 true JP5726350B2 (en) | 2015-05-27 |
Family
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