JPH0763992A - Zoom lens and image pickup device using the same - Google Patents
Zoom lens and image pickup device using the sameInfo
- Publication number
- JPH0763992A JPH0763992A JP5234097A JP23409793A JPH0763992A JP H0763992 A JPH0763992 A JP H0763992A JP 5234097 A JP5234097 A JP 5234097A JP 23409793 A JP23409793 A JP 23409793A JP H0763992 A JPH0763992 A JP H0763992A
- Authority
- JP
- Japan
- Prior art keywords
- lens
- focusing
- zoom
- lens group
- group
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
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Classifications
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B15/00—Optical objectives with means for varying the magnification
- G02B15/14—Optical objectives with means for varying the magnification by axial movement of one or more lenses or groups of lenses relative to the image plane for continuously varying the equivalent focal length of the objective
- G02B15/144—Optical objectives with means for varying the magnification by axial movement of one or more lenses or groups of lenses relative to the image plane for continuously varying the equivalent focal length of the objective having four groups only
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Automatic Focus Adjustment (AREA)
- Lenses (AREA)
Abstract
Description
【0001】[0001]
【産業上の利用分野】本発明はズームレンズ及びそれを
用いた撮像装置に関し、例えば画像入力装置、スチルカ
メラ、ビデオカメラ、TVカメラ等に好適なリヤーフォ
ーカス方式を利用し、物体距離全般にわたり良好なる収
差補正を行ったものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a zoom lens and an image pickup apparatus using the same, and uses a rear focus method suitable for, for example, an image input apparatus, still camera, video camera, TV camera, etc. The following aberration correction is performed.
【0002】[0002]
【従来の技術】従来より撮像手段としてのズームレンズ
においては、そのズーム範囲全域、及び撮像可能な物体
距離全域に対して、収差補正状態が良好であることが必
要であり、且つ、レンズ系全体が小型で軽量であること
が望まれている。2. Description of the Related Art Conventionally, in a zoom lens as an image pickup means, it is necessary that the aberration correction state be good over the entire zoom range and the entire imageable object distance, and the entire lens system. Is desired to be small and lightweight.
【0003】ズームレンズにおけるフォーカシング(フ
ォーカス)方法として最前方レンズ群(前玉)の全体又
はその一部を物体距離の変化に応じて光軸方向に移動さ
せることによって行う方法(前玉フォーカス方法)があ
る。As a focusing (focusing) method in a zoom lens, a method of moving all or part of the frontmost lens group (front lens) in the optical axis direction according to a change in object distance (front lens focusing method) There is.
【0004】一般に物体距離の変動に応じてフォーカス
を行うと収差が変動してくる。このときのフォーカスの
際の収差変動を少なくする為には前玉であるフォーカス
レンズ群単独で収差補正しておく必要がある。Generally, when focusing is performed according to the variation of the object distance, the aberration varies. In this case, in order to reduce the fluctuation of aberration during focusing, it is necessary to correct the aberration of the focus lens group as the front lens alone.
【0005】しかしながらこの場合には前玉のレンズ枚
数が多くなり且つレンズ構成が複雑化してくるという問
題点がある。又、従来の多くのズームレンズでは近距離
の物体にピントを合わせる為に前玉のみを繰り出す場
合、光線のケラレ等を考えて、予め前玉の有効径を大き
く取っている。However, in this case, there are problems that the number of lenses of the front lens increases and the lens structure becomes complicated. Further, in many conventional zoom lenses, when only the front lens is projected to focus on an object at a short distance, the effective diameter of the front lens is set to be large in advance in consideration of vignetting of light rays.
【0006】この為、単純な前玉フォーカス方式を採用
すると多くの場合、前玉が大型化し、及び高重量化して
くるという問題点がある。Therefore, when the simple front lens focus system is adopted, there are many problems that the front lens becomes large in size and heavy in weight.
【0007】これらの問題点を解決する一つの手段とし
て、前玉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のズームレンズが知られて
いる。As one means for solving these problems, a so-called rear focus type zoom lens in which a lens group other than the front lens is moved to perform focusing is known.
【0008】一般にリヤーフォーカス式のズームレンズ
は前玉を移動させてフォーカスを行うズームレンズに比
べて前玉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、又近接撮影、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。Generally, in a rear focus type zoom lens, the effective diameter of the front lens is smaller than that of a zoom lens in which the front lens is moved to perform focusing, which facilitates downsizing of the entire lens system and close-up photography, particularly Since close-up photography is facilitated, and because the relatively small and lightweight lens group is moved, the driving force of the lens group is small and quick focusing is possible.
【0009】しかし、従来実用化されつつある移動群数
の少ないズームレンズ方式では、各群のパワーの負担が
大きく、群移動の自由度が小さい為、インナーフォーカ
シング方式やリアフォーカシング方式ではズーミングや
フォーカシングに伴う収差変動が生じ易い。However, in the conventional zoom lens system having a small number of moving groups, the power of each group is large and the degree of freedom of group movement is small. Therefore, in the inner focusing method and the rear focusing method, zooming and focusing are performed. Aberration variation easily occurs due to.
【0010】このような収差変動に対処する方法とし
て、合焦用レンズ群自体を複数の合焦移動群で構成し、
合焦動作即ちフォーカシングを行うときは、これら合焦
移動群の間の間隔を変えることにより、上記収差変動を
補正する方法が行われている。この方法の一例として特
開昭61−97618号公報記載のものを挙げることが
できる。As a method of coping with such variation in aberration, the focusing lens group itself is composed of a plurality of focusing movement groups,
When performing a focusing operation, that is, focusing, a method of correcting the above-mentioned aberration variation is performed by changing the interval between these focusing movement groups. As an example of this method, the method described in JP-A-61-97618 can be mentioned.
【0011】合焦移動群間の距離を変えてフォーカシン
グを行うことは、フォーカシングに伴う収差変動を補正
する上で有効ではあるが、従来知られている方法では、
各合焦移動群間の移動距離の比がズーム点に対して一定
であり、これは合焦動作を行う為の機構の面では好まし
いが、収差変動の補正という面からすると必ずしも十分
ではない。Focusing by changing the distance between the focus moving groups is effective in correcting the aberration variation due to focusing, but in the conventionally known method,
The ratio of the moving distance between the respective focus moving groups is constant with respect to the zoom point, which is preferable in terms of the mechanism for performing the focusing operation, but is not necessarily sufficient in terms of correction of aberration variation.
【0012】この問題点を解決する為に特開平1−27
1717号公報において、ズーミングに対してはそれぞ
れ一体的に移動する3群以上のズーム用レンズ群を持
ち、最前方以外の1以上のズーム用レンズ群を合焦用レ
ンズ群として用い、各合焦用レンズ群が合焦動作時に互
いに異なる移動量で移動する合焦移動群を有するズーム
レンズにおいてズーミングに応じて合焦を行う方法が開
示されている。To solve this problem, Japanese Patent Laid-Open No. 1-27
In Japanese Patent No. 1717, there are three or more zoom lens groups that move integrally with respect to zooming, and one or more zoom lens groups other than the foremost one are used as focusing lens groups. There is disclosed a method for performing focusing in accordance with zooming in a zoom lens having a focusing movement group in which the working lens group moves at different movement amounts during the focusing operation.
【0013】[0013]
【発明が解決しようとする課題】しかしながら、特開平
1−271717号公報に開示された方法においては、
合焦用レンズ群を最前方以外のズーム用レンズ群とし、
合焦移動群の移動比率を収差変動補正のみを考慮して決
定しているために、近距離物点に合焦したときのズーム
比が無限遠物点に合焦時のズーム比より大幅に減少し易
いという問題点がある。However, in the method disclosed in Japanese Patent Application Laid-Open No. 1-271717,
The focusing lens group is a zoom lens group other than the frontmost lens group,
The zoom ratio when focusing on a near object point is significantly larger than the zoom ratio when focusing on an object point at infinity because the moving ratio of the focus moving group is determined only by correcting aberration fluctuations. There is a problem that it tends to decrease.
【0014】例えば特開平1−271717号公報の実
施例のレンズにおいては、無限遠物点に対するズーム比
3.64に対し、最短撮影距離1.2mに対するズーム
比は3.24となっており、約11%のズーム比の低下
が見られる。この程度のズーム比の低下となると性能
上、望ましくない場合が多い。For example, in the lens of the embodiment disclosed in Japanese Patent Laid-Open No. 1-271717, the zoom ratio for the object point at infinity is 3.64, whereas the zoom ratio for the shortest shooting distance of 1.2 m is 3.24. A reduction in zoom ratio of about 11% is seen. When the zoom ratio is reduced to this extent, it is often undesirable in terms of performance.
【0015】本発明はレンズ系中のうち、最前方レンズ
群を含む少なくとも2つ以上のレンズブロック(レンズ
群の全体又はその一部)を用いてフォーカシングを行
い、ズーム位置に応じてフォーカスに寄与するレンズブ
ロック、又はレンズブロック同士の移動比率を変化させ
ることにより、あらゆるズーム位置において物体距離の
変化に伴うフォーカシングによる収差の悪化を最少限に
抑え、物体距離全般にわたり高い光学性能を有するとと
もに、近距離物体に合焦した際のズーム比の低下の少な
いズームレンズ及びそれを用いた撮像装置の提供を目的
とする。In the present invention, focusing is performed by using at least two or more lens blocks (the whole or a part of the lens group) including the frontmost lens group in the lens system, and contributes to the focus according to the zoom position. By changing the lens block to move or the moving ratio of lens blocks to each other, deterioration of aberration due to focusing due to change of object distance at all zoom positions is minimized, and high optical performance is achieved over the entire object distance. An object of the present invention is to provide a zoom lens and an image pickup apparatus using the zoom lens in which the zoom ratio does not decrease when focusing on a distance object.
【0016】[0016]
【課題を解決するための手段】本発明のズームレンズ
は、変倍の為に光軸上移動する変倍レンズ群と変倍に伴
う像面変動を補正する補正レンズ群を含む複数のレンズ
群を有し、該複数のレンズ群のうちの最前方レンズ群を
含む少なくとも2つのレンズ群を光軸上ズーム位置に応
じて異なった比率で移動させてフォーカスを行ったこと
を特徴としている。A zoom lens according to the present invention comprises a plurality of lens groups including a zoom lens group that moves on the optical axis for zooming and a correction lens group that corrects image plane fluctuations associated with zooming. Of the plurality of lens groups, at least two lens groups including the frontmost lens group are moved at different ratios according to the zoom position on the optical axis for focusing.
【0017】最前方レンズ群から同距離の物体に対する
最前方レンズ群の倍率はズーム位置に無関係に常に一定
である為、前玉フォーカスを行うズームレンズにおいて
はズーム比の低下が生じない。Since the magnification of the forefront lens group with respect to an object at the same distance from the forefront lens group is always constant irrespective of the zoom position, the zoom ratio does not decrease in the zoom lens for focusing the front lens.
【0018】この為、本発明におけるフォーカシング方
法では、フォーカシングブロックの一つに最前方レンズ
群を用いることで、ズーム比低下の低減効果を得てい
る。Therefore, in the focusing method of the present invention, the effect of reducing the reduction in zoom ratio is obtained by using the frontmost lens group as one of the focusing blocks.
【0019】又、リアフォーカス方式においては一般に
望遠側で合焦の為の移動量が大きい為、望遠側でフォー
カシングによる収差の変動が激しい。Further, in the rear focus system, the amount of movement for focusing is generally large on the telephoto side, so that aberrations due to focusing on the telephoto side vary greatly.
【0020】望遠側では、最前方レンズ群を通る軸上光
線の高さが高い為最前方レンズ群の収差変動への影響が
大きく、最前方レンズ群をフォーカシングレンズ群とし
て用いることにより、最前方レンズ群以外のフォーカシ
ングレンズ群により生じた収差を効果的に低減できると
いう効果もある。On the telephoto side, since the height of the axial ray passing through the frontmost lens group is high, the influence on the aberration variation of the frontmost lens group is large, and by using the frontmost lens group as the focusing lens group, There is also an effect that the aberration caused by the focusing lens group other than the lens group can be effectively reduced.
【0021】更に、無限遠物点に合焦した状態を基準と
して、有限距離物点に合焦した際の広角端と望遠端での
最前方レンズ群の移動量をそれぞれX1W ,X1Tとする
とき、 |X1T|>|X1W| ・・・・・・(1) とすることが望ましい。Further, with reference to the state of focusing on an object point at infinity, the movement amounts of the frontmost lens groups at the wide-angle end and the telephoto end when focused on an object point at a finite distance are X 1W and X 1T , respectively. In this case, it is desirable that | X 1T |> | X 1W |
【0022】上記(1)式に従うときの意義として、以
下のような点が挙げられる。The following points can be given as meanings when the above equation (1) is followed.
【0023】イ.前玉フォーカスで問題とされていた至
近距離物体に対する光線のケラレは広角側で激しくなる
が、上記(1)式を満足することで前玉径増大の防止に
役立つ。A. Although the vignetting of a light beam on an object at a close range, which has been a problem in front-lens focusing, becomes severe on the wide-angle side, satisfying the above formula (1) helps prevent the front-lens diameter from increasing.
【0024】ロ.前玉以外のフォーカシングレンズ群の
移動量は一般に広角側に比べ望遠側で非常に大きいため
望遠端での前玉移動量を大きくしたことにより、前玉以
外のフォーカシングレンズ群の移動量の広角端と望遠端
での差異を軽減でき、コンパクト化、至近距離物点合焦
時のズーム比低減の防止、フォーカシングによる収差変
動の低減等に役立つ。B. Since the amount of movement of the focusing lens group other than the front lens is generally much larger on the telephoto side than on the wide angle side, the amount of movement of the front lens at the telephoto end was increased to make the amount of movement of the focusing lens group other than the front lens wide-angle end. The difference at the telephoto end can be reduced, which is useful for downsizing, prevention of reduction in zoom ratio when focusing on an object at a close range, and reduction of aberration variation due to focusing.
【0025】又本発明のズームレンズを用いた撮像装置
は、物体距離情報を検出する距離検出手段、ズーム位置
に対応したフォーカスに必要なデータを記憶した記憶手
段そして少なくとも変倍の為に光軸上移動する変倍レン
ズ群と変倍に伴う像面変動を補正する補正レンズを含む
複数のレンズ群とを有し、該距離検出手段からの距離情
報と記憶手段からのデータとを用いて制御手段により、
該複数のレンズ群のうちの少なくとも2つのレンズ群を
光軸上ズーム位置に応じて異なった比率で移動させてフ
ォーカスを行うようにしたことを特徴としている。Further, the image pickup apparatus using the zoom lens of the present invention comprises a distance detecting means for detecting object distance information, a storing means for storing data necessary for focusing corresponding to the zoom position, and an optical axis for zooming at least. A variable power lens group that moves upward and a plurality of lens groups including a correction lens that corrects an image plane variation due to variable power are provided, and control is performed using distance information from the distance detection means and data from the storage means. By means
It is characterized in that at least two lens groups of the plurality of lens groups are moved at different ratios according to the zoom position on the optical axis for focusing.
【0026】[0026]
【実施例】図1は本発明のズームレンズ及びそれを用い
た撮像装置の実施例1の要部概略図、図2は図1のズー
ムレンズの後述する数値実施例1の広角端のレンズ断面
図である。Embodiment 1 FIG. 1 is a schematic view of a main part of Embodiment 1 of a zoom lens and an image pickup apparatus using the same according to the present invention, and FIG. 2 is a lens cross section of a zoom lens of FIG. It is a figure.
【0027】図中L1は前玉レンズ群であり、物体距離
の変化に伴い、光軸上移動させてフォーカスを行う、フ
ォーカス機能を有している。L2は変倍用の変倍レンズ
群、L3は変倍に伴う像面変動を補正する為の補正レン
ズ群、L4は結像作用をするリレーレンズ群である。リ
レーレンズ群L4はフォーカスの際に光軸上移動するリ
レー前群RFと固定のリレー後群RRの2つのレンズ群
を有している。Gは色分解光学系やフィルター等のガラ
スブロックである。In the figure, L1 is a front lens group, which has a focus function of moving along the optical axis for focusing in accordance with a change in the object distance. L2 is a variable power lens group for variable power, L3 is a correction lens group for correcting the image plane variation due to variable power, and L4 is a relay lens group that performs an image forming action. The relay lens group L4 has two lens groups, a relay front group RF that moves on the optical axis during focusing and a fixed relay rear group RR. G is a glass block such as a color separation optical system and a filter.
【0028】広角端から望遠端への変倍に際しては変倍
レンズ群L2と補正レンズ群L3を矢印の如く光軸上移
動させて行っている。When varying the magnification from the wide-angle end to the telephoto end, the variable-magnification lens unit L2 and the correction lens unit L3 are moved on the optical axis as indicated by the arrow.
【0029】フォーカスの際には前玉レンズ群L1とリ
レー前群RFをフォーカスブロックとして用い、物体距
離及びズーム位置の変化に伴って、これらのレンズ群の
移動比率を変えながら光軸上移動させて行っている。At the time of focusing, the front lens group L1 and the relay front group RF are used as a focus block and are moved on the optical axis while changing the moving ratio of these lens groups according to changes in the object distance and zoom position. I am going.
【0030】次に図1におけるフォーカス動作について
説明する。図1は所謂オートフォーカス(自動合焦操
作)の場合を例にとり示している。Next, the focus operation in FIG. 1 will be described. FIG. 1 shows an example of so-called autofocus (automatic focusing operation).
【0031】図中、A(A1〜A4)は各レンズ群を光
軸上移動させる駆動手段、B(B1〜B4)は各レンズ
群の光軸上の位置を検出する位置検出手段である。In the figure, A (A1 to A4) is drive means for moving each lens group on the optical axis, and B (B1 to B4) is position detection means for detecting the position of each lens group on the optical axis.
【0032】1は距離検出手段であり、物体距離情報を
公知の方法で検出している。2は記憶手段であり、変倍
の入力に応じた補正部の移動量、及びズーム位置情報と
物体距離情報からそのズーム位置において選定すべきフ
ォーカシングブロック並びにそれらの移動比率の情報を
記憶している。Reference numeral 1 is a distance detecting means for detecting object distance information by a known method. Reference numeral 2 denotes a storage unit that stores the amount of movement of the correction unit according to the input of the magnification change, the focusing block to be selected at the zoom position from the zoom position information and the object distance information, and the information of the moving ratio thereof. .
【0033】3は制御手段であり、距離検出手段1及び
位置検出手段Bからの情報を取り入れると共に記憶手段
2からデータを呼び込み、これらの情報を用いて各レン
ズ群を移動させる為の駆動手段Aの駆動を制御してい
る。Reference numeral 3 is a control means, which takes in information from the distance detection means 1 and the position detection means B and calls data from the storage means 2, and uses the information to drive each lens group A. Control the drive of.
【0034】本実施例ではズーミング(変倍)に際して
は制御手段3は変倍レンズ群L2の位置検出手段B2か
らの位置情報と記憶手段2内のデータから補正レンズ群
L3の移動量を算出し、補正レンズ群L3の駆動手段A
3の駆動制御を行っている。フォーカスに際しては制御
手段3は変倍レンズ群L2の位置検出手段B2からの位
置情報により記憶手段2内のデータから各レンズ群L
1,RFの中からフォーカシングブロックの選定を行
う。In this embodiment, at the time of zooming (magnification), the control means 3 calculates the amount of movement of the correction lens group L3 from the position information from the position detection means B2 of the variable magnification lens group L2 and the data in the storage means 2. , Driving means A for the correction lens group L3
3 drive control is performed. At the time of focusing, the control unit 3 uses the position information from the position detection unit B2 of the variable power lens unit L2 to obtain data from the storage unit 2 for each lens unit L.
1. Select a focusing block from RF.
【0035】そしてフォーカシングブロック同士の移動
比率を読み取り、距離検出手段1からの物体位置情報よ
り各レンズ群L1,RFの駆動手段(A1,A4)の駆
動制御を行っている。これによりフォーカスを行ってい
る。Then, the moving ratio between the focusing blocks is read, and drive control of the drive means (A1, A4) of each lens group L1, RF is performed based on the object position information from the distance detection means 1. This is the focus.
【0036】尚、本実施例において距離検出手段1を合
焦検出手段に変えて、合焦検出手段からの合焦情報に応
じてフォーカスに関する制御を行っても良い。In the present embodiment, the distance detecting means 1 may be replaced with a focus detecting means, and focus control may be performed according to the focus information from the focus detecting means.
【0037】次に図2の数値実施例1において有限距離
物体にフォーカシングする際の各ズーム位置における前
玉レンズ群L1とリレー前群RFの移動比率、並びに物
体距離無限遠時のフォーカシングブロックの位置を基準
としてレンズ第1面からの距離1mの物体にフォーカシ
ングした際の各ズーム位置における前玉レンズ群L1、
そしてリレー前群RFの移動量を表1に示す。移動量の
符号はレンズブロックが像側に動く場合を正の方向、物
体側に動く場合を負の方向とした。Next, in Numerical Embodiment 1 of FIG. 2, the moving ratio of the front lens group L1 and the relay front group RF at each zoom position when focusing on a finite object and the position of the focusing block when the object distance is infinity. The front lens group L1 at each zoom position when focusing on an object at a distance of 1 m from the first surface of the lens,
Table 1 shows the amount of movement of the relay front group RF. The sign of the amount of movement is positive when the lens block moves toward the image side and negative when the lens block moves toward the object side.
【0038】[0038]
【表1】 次に図3,図4,図5に数値実施例1のズームレンズの
それぞれ無限遠物点に対する最短焦点距離(以下「ワイ
ド」と呼び、Wと記す f=9.35mm)、中間焦点
距離(以下「ミドル」と呼び、Mと記す f=59.1
mm)、最長焦点距離(以下「テレ」と呼び、Tと記す
f=118.1mm)での収差図を示す。[Table 1] Next, in FIGS. 3, 4 and 5, the shortest focal length (hereinafter referred to as “wide”, referred to as W = f = 9.35 mm) of the zoom lens of Numerical Embodiment 1 with respect to the object point at infinity, and the intermediate focal length ( Hereinafter referred to as “middle” and referred to as M. f = 59.1
mm) and the longest focal length (hereinafter referred to as "tele" and referred to as T, f = 118.1 mm).
【0039】又図6,図7,図8に本発明によるフォー
カシングを行った際の(レンズ第1面からの、以下同
様)物体距離1mにおけるワイド、ミドル、テレでの収
差図を示す。図6〜図8に示すようにズーム位置に応じ
て2つのフォーカス群の移動比率を変化させることによ
り、各ズーム位置での収差を良好に保っているのが分か
る。Further, FIGS. 6, 7 and 8 show aberration diagrams at wide, middle and tele at an object distance of 1 m when focusing according to the present invention (from the first lens surface, the same applies hereinafter). As shown in FIGS. 6 to 8, it can be seen that the aberration at each zoom position is kept good by changing the moving ratio of the two focus groups according to the zoom position.
【0040】尚参考の為に図9,図10,図11に物体
距離1mにおいて前玉のみでフォーカスを行った際のワ
イド、ミドル、テレでの収差図を示す。For reference, FIGS. 9, 10 and 11 show wide-angle, middle-angle and telescopic aberration diagrams when focusing is performed with only the front lens at an object distance of 1 m.
【0041】図11に示すように前玉のみでフォーカス
を行うと、テレ側に行くに従って収差の悪化が著しくな
ってくる。As shown in FIG. 11, when focusing is performed with only the front lens, the aberration becomes more serious as it goes to the tele side.
【0042】又図12,図13,図14に物体距離1m
においてリレー前群RFのみでフォーカスを行った際の
ワイド、ミドル、テレにおける収差図を示す。この場合
も、図14に示すようにテレ側に行くに従って収差が悪
化している。The object distance of 1 m is shown in FIGS. 12, 13 and 14.
6A and 6B show aberration diagrams in wide, middle, and tele when focusing is performed only on the relay front group RF. Also in this case, as shown in FIG. 14, the aberration becomes worse toward the telephoto side.
【0043】一般にズーム比の大きいズームレンズにお
いては至近距離物体へのフォーカシングに伴うズーム比
の低下が生じ易いが、本実施例1におけるズームレンズ
においては、無限遠物体フォーカス時のズーム比が1
2.64と非常に大きいにも関わらず、距離1mの物体
にフォーカスしたときのズーム比は11.75で約7%
の低下にとどまっている。Generally, in a zoom lens having a large zoom ratio, the zoom ratio is likely to decrease due to focusing on an object at a close range, but in the zoom lens of the first embodiment, the zoom ratio at the time of focusing an object at infinity is 1.
Despite being very large at 2.64, the zoom ratio when focusing on an object at a distance of 1 m is 11.75, which is about 7%.
Has remained low.
【0044】尚参考の為に本実施例1においてRF群の
みで1mの物体にフォーカシングした際のズーム比は
8.30であり、ズーム比の低下は約34%である。For reference, in Example 1, the zoom ratio when focusing on an object of 1 m with only the RF group is 8.30, and the reduction of the zoom ratio is about 34%.
【0045】以上より本実施例1においてはズーム比の
低下が効果的に抑えられていることが分かる。From the above, it can be seen that the reduction of the zoom ratio is effectively suppressed in the first embodiment.
【0046】又一般に本実施例に係るタイプのズームレ
ンズにおいて前玉フォーカス方式を採用する場合には特
にワイド端で至近距離の物体に合焦する為に前玉を繰り
出した際の光線のケラレ等を考慮して前玉の径を予め大
きくとっている。In general, when the front lens focusing system is adopted in the zoom lens of the type according to the present embodiment, vignetting of light rays when the front lens is extended in order to focus on an object at a close range particularly at the wide end. Considering the above, the diameter of the front lens is made large in advance.
【0047】これに対して本発明の表1に示す実施例1
におけるフォーカス方式によればワイドで前玉を繰り出
さない為に前玉径の小型化が可能である。On the other hand, Example 1 shown in Table 1 of the present invention
According to the focus system in (1), the front lens diameter is reduced because the front lens is not extended in a wide range.
【0048】更に本実施例1におけるフォーカシング方
法によればもっとも重量のある部分である前玉の移動量
を少なくしたことで、合焦スピードが速くなり、消費電
力が少なくて済む等の利点がある。Further, according to the focusing method in the first embodiment, since the moving amount of the front lens, which is the heaviest portion, is reduced, the focusing speed is increased and the power consumption is reduced. .
【0049】図15は本発明のズームレンズ及びそれを
用いた撮像装置の実施例2の要部概略図、図16は図1
5のズームレンズの後述する数値実施例2のレンズ断面
図である。FIG. 15 is a schematic view of the essential portions of Embodiment 2 of the zoom lens and the image pickup apparatus using the same according to the present invention, and FIG. 16 is FIG.
9 is a lens cross-sectional view of Numerical Example 2 of the zoom lens of No. 5 described later.
【0050】図中LL1は負の屈折力の第1群、LL2
は正の屈折力の第2群、LL3は正の屈折力の第3群で
ある。広角端から望遠端への変倍を第1群LL1と第2
群LL2との間隔が縮まり、第2群LL2と第3群LL
3との間隔が拡大するように第1群LL1,第2群LL
2,第3群LL3を光軸上図16に示すように移動させ
ている。In the figure, LL1 is the first group of negative refracting power, LL2
Is a second group having a positive refractive power, and LL3 is a third group having a positive refractive power. Zooming from the wide-angle end to the telephoto end is performed with the first lens unit LL1 and the second lens unit.
The distance from the group LL2 is reduced, and the second group LL2 and the third group LL
The first group LL1 and the second group LL so that the distance from
The second and third lens units LL3 are moved along the optical axis as shown in FIG.
【0051】本実施例では第1群LL1と第3群LL3
をフォーカシングブロックとして選択し、各レンズ群の
移動比率をズーム位置毎に変えることによりフォーカス
の際の収差変動を少なくし、物体距離全般にわたり高い
光学性能を得ている。In this embodiment, the first group LL1 and the third group LL3
Is selected as the focusing block, and the movement ratio of each lens unit is changed for each zoom position to reduce aberration fluctuations during focusing and obtain high optical performance over the entire object distance.
【0052】ズーミング及びフォーカスによる可動レン
ズブロックの制御は前述した実施例1と同様な方式によ
り行っている。Control of the movable lens block by zooming and focusing is performed in the same manner as in the first embodiment.
【0053】図16の数値実施例2において有限距離物
体にフォーカシングする際の各ズーム位置における第1
群LL1と第3群LL3の移動比率、並びに物体距離無
限遠時のフォーカシングブロックの位置を基準として、
像面からの距離50cmの物体にフォーカシングした際
の各ズーム位置における第1群LL1及び第3群LL3
群LL3の移動量を表2に示す。符号はレンズブロック
が像側に動く場合を正の方向、物体側に動く場合を負の
方向とした。The first example at each zoom position when focusing on a finite distance object in the numerical example 2 of FIG.
Based on the moving ratio of the group LL1 and the third group LL3, and the position of the focusing block when the object distance is infinity,
The first group LL1 and the third group LL3 at each zoom position when focusing on an object at a distance of 50 cm from the image plane
Table 2 shows the movement amount of the group LL3. Signs are positive when the lens block moves toward the image side and negative when the lens block moves toward the object side.
【0054】又本実施例2のズームレンズの無限遠物体
フォーカス時のズーム比は2.01であり、50cmの
物体にフォーカスした時のズーム比も2.01となって
おり、上記のフォーカシング方法を用いることによりフ
ォーカシングに伴うズーム比の低下のないズームレンズ
を達成している。Further, the zoom lens of Embodiment 2 has a zoom ratio of 2.01 when focusing on an object at infinity and a zoom ratio of 2.01 when focusing on an object of 50 cm, which is the above focusing method. By using, a zoom lens without a reduction in zoom ratio due to focusing is achieved.
【0055】[0055]
【表2】 次に図17,図18,図19に数値実施例2のズームレ
ンズのそれぞれ無限遠物点に対するワイド(f=24.
4mm)、ミドル(f=34.9mm)、テレ(f=4
9.0mm)での収差図を示す。[Table 2] Next, in FIGS. 17, 18 and 19, the zoom lens of Numerical Example 2 has a wide range (f = 24.
4mm), middle (f = 34.9mm), tele (f = 4)
The aberration figure in (9.0 mm) is shown.
【0056】図20,図21,図22に本実施例2にお
ける第1群LL1と第3群LL3の移動比率をズーム位
置毎に変えてフォーカシングを行った際の(像面から
の、以下同様)物体距離50cmでのワイド、ミドル、
テレの収差図を示す。20, FIG. 21, and FIG. 22 are shown when focusing is performed by changing the moving ratio of the first lens group LL1 and the third lens group LL3 for each zoom position in the second embodiment (from the image plane, the same applies hereinafter. ) Wide, middle, at an object distance of 50 cm
The aberration figure of tele is shown.
【0057】又参考の為に図23,図24,図25に第
3群LL3のみでフォーカスを行ったときの物体距離5
0cmでのワイド、ミドル、テレでの収差図を示す。For reference, in FIG. 23, FIG. 24, and FIG. 25, the object distance 5 when only the third lens group LL3 is focused.
Aberration diagrams at wide, middle, and tele at 0 cm are shown.
【0058】図20〜図25より明かのように本発明に
係るフォーカシング方法を用いればズーム範囲全域にお
いて至近距離の物体にフォーカシングするときの諸収差
の発生を効果的に防止することができる。As can be seen from FIGS. 20 to 25, by using the focusing method according to the present invention, it is possible to effectively prevent the occurrence of various aberrations when focusing on an object at a close range in the entire zoom range.
【0059】図26は本発明のズームレンズ及びそれを
用いた撮像装置の実施例3の要部概略図、図27は図2
6のズームレンズの後述する数値実施例3のレンズ断面
図、並びに変倍の為の各群の移動の仕方を示した図であ
る。FIG. 26 is a schematic view of the essential portions of Embodiment 3 of the zoom lens and the image pickup apparatus using the same according to the present invention, and FIG.
FIG. 9 is a lens cross-sectional view of Numerical Example 3 to be described later of the zoom lens of No. 6 and a diagram showing how to move each group for zooming.
【0060】図中LLL1は正の屈折力の第1群、LL
L2は負の屈折力の第2群、LLL3は正の屈折力の第
3群である。In the figure, LLL1 is the first group of positive refracting power, LL
L2 is a second group having a negative refractive power, and LLL3 is a third group having a positive refractive power.
【0061】広角端から望遠端への変倍を第2群LLL
2を固定とし、第1群LLL1と第3群LLL3とを光
軸上、図27に示すように物体側(図の左方向)に移動
させることにより行う。Zooming from the wide-angle end to the telephoto end is performed by the second lens unit LLL.
2 is fixed, and the first group LLL1 and the third group LLL3 are moved toward the object side (leftward in the figure) on the optical axis as shown in FIG.
【0062】上記の通り、本実施例3のズームレンズは
特開平1−271717に開示された実施例のズームレ
ンズと同様の構成となっている。As described above, the zoom lens of the third embodiment has the same structure as the zoom lens of the embodiment disclosed in Japanese Patent Laid-Open No. 1-271717.
【0063】本実施例3では第3群LLL3をLLL3
a,LLL3b,LLL3cの3つのブロックに分け、
第1群LLL1とレンズ群LLL3b,LLL3cをフ
ォーカシングブロックとして選択し、各レンズ群の移動
比率をズーム位置毎に変えることにより、フォーカスの
際の収差変動を少なくし、物体距離全般にわたり高い光
学性能を得ると共にズーム比の低下を防止している。ズ
ーミング及びフォーカスによる可動レンズブロックの制
御は前述の実施例1,2と同様な方式により行ってい
る。In the third embodiment, the third lens unit LLL3 is set to LLL3.
a, LLL3b, LLL3c divided into three blocks,
By selecting the first group LLL1 and the lens groups LLL3b and LLL3c as focusing blocks, and changing the moving ratio of each lens group for each zoom position, the aberration variation during focusing is reduced, and high optical performance is achieved over the entire object distance. In addition, the zoom ratio is prevented from decreasing. The control of the movable lens block by zooming and focusing is performed by the same method as in the first and second embodiments.
【0064】図27の数値実施例3において、物体距離
無限遠時のフォーカシングブロックの位置を基準とし
て、有限距離物体にフォーカシングする際の各ズーム位
置における第1群LLL1及び第3群LLL3中のレン
ズブロックLLL3b、LLL3cの移動比率、並びに
(像面からの、以下同様)距離1.2mの物体にフォー
カシングした際の各ズーム位置における移動量を表3に
示す。符号はレンズブロックが像側に動く場合を正の方
向、物体側に動く場合を負の方向とした。In Numerical Example 3 of FIG. 27, the lens in the first lens unit LLL1 and the third lens unit LLL3 at each zoom position when focusing on a finite object with reference to the position of the focusing block when the object distance is infinity. Table 3 shows the moving ratios of the blocks LLL3b and LLL3c, and the moving amount at each zoom position when focusing on an object at a distance of 1.2 m (from the image plane, the same applies below). Signs are positive when the lens block moves toward the image side and negative when the lens block moves toward the object side.
【0065】[0065]
【表3】 次に図28,図29,図30に数値実施例3のズームレ
ンズのそれぞれ無限遠物点に対するワイド(f=36.
0mm)、ミドル(f=68.7mm)、テレ(f=1
31.3mm)での収差図を示す。[Table 3] Next, FIGS. 28, 29, and 30 show a wide range (f = 36.
0mm), middle (f = 68.7mm), tele (f = 1)
The aberration figure in 31.3 mm) is shown.
【0066】図31,図32,図33に本実施例3にお
ける第1群LLL1と第3群中のレンズブロックLLL
3b,LLL3cの移動比率をズーム位置毎に変えてフ
ォーカシングを行った際の物体距離1.2mでのワイ
ド、ミドル、テレでの収差図を示す。31, 32, and 33, the first group LLL1 and the lens block LLL in the third group according to the third embodiment.
The aberration figure in wide, middle, and tele in the object distance 1.2m when focusing is performed by changing the moving ratio of 3b and LLL3c for every zoom position is shown.
【0067】図31〜図33に示したとおり、本発明に
係るフォーカシング方法を用いれば、ズーム範囲全域に
おいて至近距離の物体にフォーカシングするときの諸収
差の発生を効果的に防止することができる。As shown in FIGS. 31 to 33, by using the focusing method according to the present invention, it is possible to effectively prevent the occurrence of various aberrations when focusing on an object at a close range in the entire zoom range.
【0068】又本実施例3においては物体距離無限遠時
のズーム比3.64に対し、1.2mの物体にフォーカ
シングした際のズーム比は3.87であり、特開平1−
271717に開示された実施例のズームレンズと同様
の構成でありながら、フォーカシングに伴うズーム比の
低下が生じないようにすることができる。Further, in the third embodiment, the zoom ratio when focusing on an object of 1.2 m is 3.87, whereas the zoom ratio when the object distance is infinity is 3.64, which is 3.87.
Although the zoom lens has the same configuration as the zoom lens of the embodiment disclosed in No. 271717, it is possible to prevent the zoom ratio from being lowered due to focusing.
【0069】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 shown. 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 gap from the object side, and Ni and νi are respectively from the object side in the i-th lens. The refractive index of glass and the Abbe number.
【0070】(数値実施例1) f= 9.345 fno=1:1.7 2ω= 61.0° R 1=-2337.70 D 1= 2.50 N 1=1.80518 ν 1= 25.4 R 2= 107.51 D 2= 3.84 R 3= 330.35 D 3= 8.40 N 2=1.43387 ν 2= 95.1 R 4= -123.70 D 4= 0.15 R 5= 181.98 D 5= 8.36 N 3=1.49700 ν 3= 81.6 R 6= -158.76 D 6= 0.15 R 7= 52.34 D 7= 10.76 N 4=1.69680 ν 4= 55.5 R 8= 237.88 D 8= 可変 R 9= 61.10 D 9= 1.00 N 5=1.88300 ν 5= 40.8 R10= 18.77 D10= 3.80 R11= -63.98 D11= 0.80 N 6=1.80400 ν 6= 46.6 R12= 82.33 D12= 3.76 R13= -16.14 D13= 0.80 N 7=1.77250 ν 7= 49.6 R14= 307.48 D14= 3.20 N 8=1.92286 ν 8= 21.3 R15= -28.88 D15= 可変 R16= -26.20 D16= 0.90 N 9=1.77250 ν 9= 49.6 R17= 29.28 D17= 3.70 N10=1.80518 ν10= 25.4 R18= -786.13 D18= 可変 R19= ∞(絞り) D19= 2.24 R20= -160.22 D20= 3.88 N11=1.58144 ν11= 40.8 R21= -35.70 D21= 0.15 R22= 82.00 D22= 10.11 N12=1.56732 ν12= 42.8 R23= -21.90 D23= 1.20 N13=1.88300 ν13= 40.8 R24= -73.59 D24= 14.87 R25= 65.40 D25= 9.55 N14=1.51112 ν14= 60.5 R26= -57.48 D26= 0.15 R27=-1739.44 D27= 1.20 N15=1.88300 ν15= 40.8 R28= 37.25 D28= 10.97 N16=1.50048 ν16= 66.0 R29= -64.96 D29= 0.15 R30=10851.00 D30= 1.20 N17=1.83400 ν17= 37.2 R31= 32.11 D31= 9.89 N18=1.48749 ν18= 70.2 R32= -87.01 D32= 0.15 R33= 38.76 D33= 9.25 N19=1.48749 ν19= 70.2 R34= -121.00 D34= 2.24 R35= ∞ D35= 65.00 N20=1.51633 ν20= 64.2 R36= ∞Numerical Example 1 f = 9.345 fno = 1: 1.7 2ω = 61.0 ° R 1 = -2337.70 D 1 = 2.50 N 1 = 1.80518 ν 1 = 25.4 R 2 = 107.51 D 2 = 3.84 R 3 = 330.35 D 3 = 8.40 N 2 = 1.43387 ν 2 = 95.1 R 4 = -123.70 D 4 = 0.15 R 5 = 181.98 D 5 = 8.36 N 3 = 1.49700 ν 3 = 81.6 R 6 = -158.76 D 6 = 0.15 R 7 = 52.34 D 7 = 10.76 N 4 = 1.69680 ν 4 = 55.5 R 8 = 237.88 D 8 = Variable R 9 = 61.10 D 9 = 1.00 N 5 = 1.88 300 ν 5 = 40.8 R10 = 18.77 D10 = 3.80 R11 = -63.98 D11 = 0.80 N 6 = 1.80400 ν 6 = 46.6 R12 = 82.33 D12 = 3.76 R13 = -16.14 D13 = 0.80 N 7 = 1.77250 ν 7 = 49.6 R14 = 307.48 D14 = 3.20 N 8 = 1.92286 ν 8 = 21.3 R15 = -28.88 D15 = variable R16 = -26.20 D16 = 0.90 N 9 = 1.77250 ν 9 = 49.6 R17 = 29.28 D17 = 3.70 N10 = 1.80518 ν10 = 25.4 R18 = -786.13 D18 = variable R19 = ∞ (diaphragm) D19 = 2.24 R20 = -160.22 D20 = 3.88 N11 = 1.58144 ν11 = 40.8 R21 = -35.70 D21 = 0.15 R22 = 82.00 D22 = 10.11 N12 = 1.56732 ν12 = 42.8 R23 = -21.90 D23 = 1.20 N13 = 1.88300 ν13 = 40.8 R24 = -73.59 D24 = 14.87 R25 = 65.40 D25 = 9.55 N14 = 1.51112 ν14 = 60.5 R26 = -57.48 D26 = 0.15 R27 = -1739.44 D27 = 1.20 N15 = 1.88300 ν15 = 40.8 R28 = 37.25 D28 = 10.97 N16 = 1.50048 ν16 = 66.0 R29 = -64.96 D29 = 0.15 R30 = 10851.00 D30 = 1.20 N17 = 1.83400 ν17 = 37.2 R31 = 32.11 D31 = 9.89 N18 = 1.48749 ν18 = 70.2 R32 = -87.01 D32 = 0.15 R33 = 38.76 D33 = 9.25 N19 = 1.48749 ν19 = 70.2 R34 = -121.00 D34 = 2.24 R35 = ∞ D35 = 65.00 N20 = 1.51633 ν20 = 64.2 R36 = ∞
【0071】[0071]
【表4】 (数値実施例2) f= 24.392 fno=1:2.7 2ω= 83.2° R 1= 88.53 D 1= 4.50 N 1=1.60311 ν 1= 60.7 R 2= 370.17 D 2= 0.18 R 3= 53.94 D 3= 1.40 N 2=1.79500 ν 2= 45.3 R 4= 19.65 D 4= 8.20 R 5= 203.09 D 5= 1.20 N 3=1.79500 ν 3= 45.3 R 6= 27.92 D 6= 5.46 R 7= 30.07 D 7= 3.50 N 4=1.75550 ν 4= 25.1 R 8= 71.06 D 8= 可変 R 9= 61.54 D 9= 2.64 N 5=1.60311 ν 5= 60.7 R10= -101.67 D10= 0.10 R11= 22.82 D11= 3.11 N 6=1.60311 ν 6= 60.7 R12= 58.31 D12= 2.85 R13= ∞(絞り) D13= 0.50 R14= 30.59 D14= 2.00 N 7=1.72000 ν 7= 50.3 R15= 59.93 D15= 2.00 R16= -52.46 D16= 2.80 N 8=1.74000 ν 8= 28.3 R17= 21.30 D17= 2.10 R18= -817.73 D18= 3.40 N 9=1.56732 ν 9= 42.8 R19= -21.19 D19= 可変 R20= 48.17 D20= 3.52 N10=1.60311 ν10= 60.7 R21= -74.15 D21= 0.80 N11=1.64769 ν11= 33.8 R22= 179.87[Table 4] (Numerical Example 2) f = 24.392 fno = 1: 2.7 2ω = 83.2 ° R 1 = 88.53 D 1 = 4.50 N 1 = 1.60311 ν 1 = 60.7 R 2 = 370.17 D 2 = 0.18 R 3 = 53.94 D 3 = 1.40 N 2 = 1.79500 ν 2 = 45.3 R 4 = 19.65 D 4 = 8.20 R 5 = 203.09 D 5 = 1.20 N 3 = 1.79500 ν 3 = 45.3 R 6 = 27.92 D 6 = 5.46 R 7 = 30.07 D 7 = 3.50 N 4 = 1.75550 ν 4 = 25.1 R 8 = 71.06 D 8 = Variable R 9 = 61.54 D 9 = 2.64 N 5 = 1.60311 ν 5 = 60.7 R10 = -101.67 D10 = 0.10 R11 = 22.82 D11 = 3.11 N 6 = 1.60311 ν 6 = 60.7 R12 = 58.31 D12 = 2.85 R13 = ∞ (aperture) D13 = 0.50 R14 = 30.59 D14 = 2.00 N 7 = 1.72000 ν 7 = 50.3 R15 = 59.93 D15 = 2.00 R16 = -52.46 D16 = 2.80 N 8 = 1.74000 ν 8 = 28.3 R17 = 21.30 D17 = 2.10 R18 = -817.73 D18 = 3.40 N 9 = 1.56732 ν 9 = 42.8 R19 = -21.19 D19 = Variable R20 = 48.17 D20 = 3.52 N10 = 1.60311 ν10 = 60.7 R21 = -74.15 D21 = 0.80 N11 = 1.64769 ν11 = 33.8 R22 = 179.87
【0072】[0072]
【表5】 (数値実施例3) f=36.03 fno=1:4 2ω= 62.0° R 1= 159.16 D 1= 1.80 N 1=1.80518 ν 1= 25.4 R 2= 54.76 D 2= 7.20 N 2=1.58913 ν 2= 61.2 R 3= -143.14 D 3= 0.20 R 4= 41.58 D 4= 4.20 N 3=1.62299 ν 3= 58.2 R 5= 145.13 D 5= 可変 R 6= 689.41 D 6= 1.30 N 4=1.80400 ν 4= 46.6 R 7= 17.42 D 7= 5.30 R 8= -63.26 D 8= 1.50 N 5=1.80400 ν 5= 46.6 R 9= 152.88 D 9= 0.10 R10= 26.71 D10= 4.52 N 6=1.76182 ν 6= 26.5 R11= -41.95 D11= 0.73 R12= -32.49 D12= 1.30 N 7=1.80400 ν 7= 46.6 R13= 78.60 D13= 可変 R14= ∞(絞り) D14= 1.00 R15= 35.81 D15= 2.26 N 8=1.69680 ν 8= 55.5 R16= 384.77 D16= 0.20 R17= 17.43 D17= 3.51 N 9=1.51633 ν 9= 64.2 R18= 108.32 D18= 1.63 R19= -33.96 D19= 4.20 N10=1.75520 ν10= 27.5 R20= 59.14 D20= 1.47 R21=-25805.75 D21= 4.27 N11=1.51823 ν11= 59.0 R22= -24.27 D22= 可変 R23= 32.83 D23= 4.74 N12=1.56732 ν12= 42.8 R24= -28.68 D24= 3.10 R25= -17.00 D25= 1.50 N13=1.83400 ν13= 37.2 R26= -46.82 D26= 可変 R27= -17.30 D27= 1.65 N14=1.83400 ν14= 37.2 R28= -25.99 [Table 5] (Numerical Example 3) f = 36.03 fno = 1: 4 2ω = 62.0 ° R 1 = 159.16 D 1 = 1.80 N 1 = 1.80518 ν 1 = 25.4 R 2 = 54.76 D 2 = 7.20 N 2 = 1.58913 ν 2 = 61.2 R 3 = -143.14 D 3 = 0.20 R 4 = 41.58 D 4 = 4.20 N 3 = 1.62299 ν 3 = 58.2 R 5 = 145.13 D 5 = Variable R 6 = 689.41 D 6 = 1.30 N 4 = 1.80400 ν 4 = 46.6 R 7 = 17.42 D 7 = 5.30 R 8 = -63.26 D 8 = 1.50 N 5 = 1.80400 ν 5 = 46.6 R 9 = 152.88 D 9 = 0.10 R10 = 26.71 D10 = 4.52 N 6 = 1.76182 ν 6 = 26.5 R11 = -41.95 D11 = 0.73 R12 = -32.49 D12 = 1.30 N 7 = 1.80400 ν 7 = 46.6 R13 = 78.60 D13 = Variable R14 = ∞ (Aperture) D14 = 1.00 R15 = 35.81 D15 = 2.26 N 8 = 1.69680 ν 8 = 55.5 R16 = 384.77 D16 = 0.20 R17 = 17.43 D17 = 3.51 N 9 = 1.51633 ν 9 = 64.2 R18 = 108.32 D18 = 1.63 R19 = -33.96 D19 = 4.20 N10 = 1.75520 ν10 = 27.5 R20 = 59.14 D20 = 1.47 R21 = -25805.75 D21 = 4.27 N11 = 1.51823 ν11 = 59.0 R22 = -24.27 D22 = Variable R23 = 32.83 D23 = 4.74 N12 = 1.56732 ν12 = 42.8 R24 = -28.68 D24 = 3.10 R25 = -17.00 D25 = 1.50 N13 = 1.83400 ν13 = 37.2 R26 = -46.82 D26 = Variable R27 = -17.30 D27 = 1.65 N14 = 1.83400 ν14 = 37.2 R28 = -25.99
【0073】[0073]
【表6】 [Table 6]
【0074】[0074]
【発明の効果】本発明によれば以上のように、レンズ系
中のうち、最前方レンズ群を含む少なくとも2つ以上の
レンズブロック(レンズ群の全体又はその一部)を用い
てフォーカシングを行い、ズーム位置に応じてフォーカ
スに寄与するレンズブロック、又はレンズブロック同士
の移動比率を変化させることにより、あらゆるズーム位
置において物体距離の変化に伴うフォーカシングによる
収差の悪化を最少限に抑え、物体距離全般にわたり高い
光学性能を有するとともに、近距離物体に合焦した際の
ズーム比の低下の少ないズームレンズ及びそれを用いた
撮像装置を達成することができる。As described above, according to the present invention, focusing is performed using at least two or more lens blocks (the whole lens group or a part thereof) of the lens system including the frontmost lens group. , By changing the lens block that contributes to focus depending on the zoom position or the moving ratio of the lens blocks to each other, the deterioration of aberration due to focusing due to the change of the object distance at any zoom position is minimized, and the overall object distance is reduced. Thus, it is possible to achieve a zoom lens having high optical performance over a wide range and having a small reduction in zoom ratio when focusing on a short-distance object, and an image pickup apparatus using the zoom lens.
【図1】 本発明のズームレンズ及びそれを用いた撮像
装置の実施例1の要部概略図FIG. 1 is a schematic diagram of a main part of a zoom lens of the present invention and an image pickup apparatus using the same according to a first embodiment.
【図2】 図1のズームレンズのレンズ断面図FIG. 2 is a lens cross-sectional view of the zoom lens of FIG.
【図3】 本発明のズームレンズの数値実施例1の無限
遠物体に対するワイドの収差図FIG. 3 is a wide aberration diagram of a numerical example 1 of the zoom lens of the present invention with respect to an object at infinity.
【図4】 本発明のズームレンズの数値実施例1の無限
遠物体に対するミドルの収差図FIG. 4 is an aberration diagram of middle for an object at infinity according to Numerical Example 1 of the zoom lens of the present invention.
【図5】 本発明のズームレンズの数値実施例1の無限
遠物体に対するテレの収差図FIG. 5 is a telescopic aberration diagram for an object at infinity according to Numerical Example 1 of the zoom lens of the present invention.
【図6】 本発明のズームレンズの数値実施例1の物体
距離1mに対する本発明に係るフォーカシングを用いた
ときのワイドの収差図FIG. 6 is a wide aberration diagram when the focusing according to the present invention is used for an object distance of 1 m in Numerical Example 1 of the zoom lens of the present invention.
【図7】 本発明のズームレンズの数値実施例1の物体
距離1mに対する本発明に係るフォーカシングを用いた
ときのミドルの収差図FIG. 7 is an aberration diagram of the middle when the focusing according to the present invention is used for the object distance of 1 m in Numerical Example 1 of the zoom lens of the present invention.
【図8】 本発明のズームレンズの数値実施例1の物体
距離1mに対する本発明に係るフォーカシングを用いた
ときのテレの収差図FIG. 8 is a telescopic aberration diagram when the focusing according to the present invention is used for an object distance of 1 m in Numerical Example 1 of the zoom lens of the present invention.
【図9】 本発明のズームレンズの数値実施例1の物体
距離1mの前玉フォーカスによるワイドの収差図FIG. 9 is a wide aberration diagram of the first embodiment of the zoom lens according to the present invention when the front lens is focused with an object distance of 1 m.
【図10】 本発明のズームレンズの数値実施例1の物
体距離1mの前玉フォーカスによるミドルの収差図FIG. 10 is an aberration diagram of a middle lens of Numerical Example 1 of the zoom lens according to the present invention when the front lens is focused at an object distance of 1 m.
【図11】 本発明のズームレンズの数値実施例1の物
体距離1mの前玉フォーカスによるテレの収差図FIG. 11 is a telescopic aberration diagram of a front lens focus of an object distance of 1 m according to Numerical Example 1 of the zoom lens of the present invention.
【図12】 本発明のズームレンズの数値実施例1の物
体距離1mのリレー前群RFによるワイドの収差図FIG. 12 is a wide aberration diagram of the front lens group RF of the relay with an object distance of 1 m according to Numerical Example 1 of the zoom lens of the present invention.
【図13】 本発明のズームレンズの数値実施例1の物
体距離1mのリレー前群RFによるミドルの収差図FIG. 13 is an aberration diagram of a middle lens due to a relay front group RF with an object distance of 1 m in Numerical Example 1 of the zoom lens of the present invention.
【図14】 本発明のズームレンズの数値実施例1の物
体距離1mのリレー前群RFによるテレの収差図FIG. 14 is a telescopic aberration diagram of a relay front unit RF with an object distance of 1 m according to Numerical Example 1 of the zoom lens of the present invention.
【図15】 本発明のズームレンズ及びそれを用いた撮
像装置の実施例2の要部概略図FIG. 15 is a schematic view of the essential portions of Embodiment 2 of the zoom lens of the present invention and an image pickup apparatus using the same.
【図16】 図15のズームレンズのレンズ断面図16 is a lens cross-sectional view of the zoom lens of FIG.
【図17】 本発明のズームレンズの数値実施例2の無
限遠物体に対するワイドの収差図FIG. 17 is a wide aberration diagram of the numerical example 2 of the zoom lens of the present invention with respect to an object at infinity.
【図18】 本発明のズームレンズの数値実施例2の無
限遠物体に対するミドルの収差図FIG. 18 is an aberration diagram of middle for an object at infinity according to Numerical Example 2 of the zoom lens of the present invention.
【図19】 本発明のズームレンズの数値実施例2の無
限遠物体に対するテレの収差図FIG. 19 is a telescopic aberration diagram for an object at infinity according to Numerical Example 2 of the zoom lens of the present invention.
【図20】 本発明のズームレンズの数値実施例2の物
体距離50cmに対する本発明に係るフォーカシングを
用いたときのワイドの収差図FIG. 20 is a wide aberration diagram when a focusing according to the present invention is used for an object distance of 50 cm in Numerical Example 2 of the zoom lens according to the present invention.
【図21】 本発明のズームレンズの数値実施例2の物
体距離50cmに対する本発明に係るフォーカシングを
用いたときのミドルの収差図FIG. 21 is a middle aberration diagram when the focusing according to the present invention is used for an object distance of 50 cm in Numerical Example 2 of the zoom lens of the present invention.
【図22】 本発明のズームレンズの数値実施例2の物
体距離50cmに対する本発明に係るフォーカシングを
用いたときのテレの収差図FIG. 22 is a telescopic aberration diagram when a focusing according to the present invention is used for an object distance of 50 cm in Numerical Example 2 of the zoom lens according to the present invention.
【図23】 本発明のズームレンズの数値実施例2の物
体距離50cmに対する第3群でフォーカスを行ったと
きのワイドの収差図FIG. 23 is a wide aberration diagram when focusing is performed by the third lens group with respect to an object distance of 50 cm in Numerical Example 2 of the zoom lens of the present invention.
【図24】 本発明のズームレンズの数値実施例2の物
体距離50cmに対する第3群でフォーカスを行ったと
きのミドルの収差図FIG. 24 is an aberration diagram of a middle portion of the numerical value example 2 of the zoom lens of the present invention when the object distance is 50 cm and focusing is performed by the third group.
【図25】 本発明のズームレンズの数値実施例2の物
体距離50cmに対する第3群でフォーカスを行ったと
きのテレの収差図FIG. 25 is a telescopic aberration diagram when focusing is performed by the third group with respect to an object distance of 50 cm in Numerical Example 2 of the zoom lens of the present invention.
【図26】 本発明のズームレンズ及びそれを用いた撮
像装置の実施例3の要部概略図FIG. 26 is a schematic view of the essential parts of Embodiment 3 of the zoom lens of the present invention and an image pickup apparatus using the same.
【図27】 図26のズームレンズのレンズ断面図27 is a lens cross-sectional view of the zoom lens in FIG.
【図28】 本発明のズームレンズの数値実施例3の無
限遠物体に対するワイドの収差図FIG. 28 is a wide aberration diagram of the numerical example 3 of the zoom lens of the present invention with respect to an object at infinity.
【図29】 本発明のズームレンズの数値実施例3の無
限遠物体に対するミドルの収差図FIG. 29 is an aberration diagram of middle for an infinitely distant object according to Numerical Example 3 of the zoom lens of the present invention.
【図30】 本発明のズームレンズの数値実施例3の無
限遠物体に対するテレの収差図FIG. 30 is a tele aberration diagram of a numerical example 3 of a zoom lens of the present invention, with respect to an object at infinity.
【図31】 本発明のズームレンズの数値実施例3の物
体距離1.2mに対する本発明に係るフォーカシング方
法を用いたときのワイドの収差図FIG. 31 is a wide aberration diagram when the focusing method according to the present invention is used for an object distance of 1.2 m in Numerical Example 3 of the zoom lens of the present invention.
【図32】 本発明のズームレンズの数値実施例3の物
体距離1.2mに対する本発明に係るフォーカシング方
法を用いたときのミドルの収差図FIG. 32 is a middle aberration diagram when a focusing method according to the present invention is used for an object distance of 1.2 m in Numerical Example 3 of the zoom lens of the present invention.
【図33】 本発明のズームレンズの数値実施例3の物
体距離1.2mに対する本発明に係るフォーカシング方
法を用いたときのテレの収差図FIG. 33 is a telescopic aberration diagram when a focusing method according to the present invention is used for an object distance of 1.2 m in Numerical Example 3 of the zoom lens of the present invention.
L1 前玉レンズ群 L2 変倍レンズ群 L3 補正レンズ群 L4 リレーレンズ群 RF リレー前群 RR リレー後群 1 距離検出手段 2 記憶手段 2 制御手段 L1 front lens group L2 variable power lens group L3 correction lens group L4 relay lens group RF relay front group RR relay rear group 1 distance detection means 2 storage means 2 control means
Claims (3)
と変倍に伴う像面変動を補正する補正レンズ群を含む複
数のレンズ群を有し、該複数のレンズ群のうちの最前方
レンズ群を含む少なくとも2つのレンズ群を光軸上ズー
ム位置に応じて異なった比率で移動させてフォーカスを
行ったことを特徴とするズームレンズ。1. A plurality of lens groups including a zoom lens group that moves on the optical axis for zooming and a correction lens group that corrects an image plane variation due to zooming, of the plurality of lens groups. A zoom lens characterized in that at least two lens groups including the foremost lens group are moved at different ratios according to the zoom position on the optical axis for focusing.
て、有限距離物点に合焦した際の、広角端と望遠端での
最前方レンズ群の移動量をそれぞれX1W ,X1Tとする
とき、 |X1T|>|X1W| であることを特徴とする請求項1のズームレンズ。2. The amount of movement of the frontmost lens unit at the wide-angle end and the telephoto end when focused on an object point at a finite distance with reference to the state of focusing on an object point at infinity is X 1W and X 1T , respectively. The zoom lens according to claim 1, wherein: | X 1T |> | X 1W |
ズーム位置に対応したフォーカスに必要なデータを記憶
した記憶手段そして少なくとも変倍の為に光軸上移動す
る変倍レンズ群と変倍に伴う像面変動を補正する補正レ
ンズを含む複数のレンズ群とを有し、該距離検出手段か
らの距離情報と記憶手段からのデータとを用いて制御手
段により、該複数のレンズ群のうちの少なくとも2つの
レンズ群を光軸上ズーム位置に応じて異なった比率で移
動させてフォーカスを行うようにしたことを特徴とする
撮像装置。3. Distance detecting means for detecting object distance information,
Storage means for storing data required for focus corresponding to zoom position, and a plurality of lens groups including at least a zoom lens group that moves on the optical axis for zooming and a correction lens that corrects image plane variation due to zooming And using the distance information from the distance detection means and the data from the storage means, the control means changes at least two lens groups of the plurality of lens groups depending on the zoom position on the optical axis. An imaging device characterized in that it is moved at different ratios to perform focusing.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP5234097A JPH0763992A (en) | 1993-08-26 | 1993-08-26 | Zoom lens and image pickup device using the same |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP5234097A JPH0763992A (en) | 1993-08-26 | 1993-08-26 | Zoom lens and image pickup device using the same |
Publications (1)
Publication Number | Publication Date |
---|---|
JPH0763992A true JPH0763992A (en) | 1995-03-10 |
Family
ID=16965580
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP5234097A Pending JPH0763992A (en) | 1993-08-26 | 1993-08-26 | Zoom lens and image pickup device using the same |
Country Status (1)
Country | Link |
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JP (1) | JPH0763992A (en) |
Cited By (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH08248312A (en) * | 1995-03-08 | 1996-09-27 | Nikon Corp | Zoom lens |
JPH11109236A (en) * | 1997-09-30 | 1999-04-23 | Minolta Co Ltd | Zoom lens system |
JP2001188169A (en) * | 1999-12-27 | 2001-07-10 | Asahi Optical Co Ltd | Zoom lens system |
WO2002082158A1 (en) * | 2001-04-02 | 2002-10-17 | Matsushita Electric Industrial Co., Ltd. | Zoom lens and electronic still camera using it |
JP2005283719A (en) * | 2004-03-29 | 2005-10-13 | Olympus Corp | Telephoto lens and telephoto lens device |
JP2009169051A (en) * | 2008-01-16 | 2009-07-30 | Canon Inc | Zoom lens and imaging apparatus having the same |
WO2013011646A1 (en) * | 2011-07-15 | 2013-01-24 | 富士フイルム株式会社 | Zoom lens and imaging device |
JP2017173680A (en) * | 2016-03-25 | 2017-09-28 | キヤノン株式会社 | Zoom lens and image capturing device having the same |
JP2020181157A (en) * | 2019-04-26 | 2020-11-05 | キヤノン株式会社 | Lens device, image capturing device, correction method, and program |
-
1993
- 1993-08-26 JP JP5234097A patent/JPH0763992A/en active Pending
Cited By (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH08248312A (en) * | 1995-03-08 | 1996-09-27 | Nikon Corp | Zoom lens |
JPH11109236A (en) * | 1997-09-30 | 1999-04-23 | Minolta Co Ltd | Zoom lens system |
JP2001188169A (en) * | 1999-12-27 | 2001-07-10 | Asahi Optical Co Ltd | Zoom lens system |
WO2002082158A1 (en) * | 2001-04-02 | 2002-10-17 | Matsushita Electric Industrial Co., Ltd. | Zoom lens and electronic still camera using it |
US6925253B2 (en) | 2001-04-02 | 2005-08-02 | Matsushita Electric Industrial Co., Ltd. | Zoom lens and electronic still camera using it |
JP4563061B2 (en) * | 2004-03-29 | 2010-10-13 | オリンパス株式会社 | Telephoto lens and telephoto lens device |
JP2005283719A (en) * | 2004-03-29 | 2005-10-13 | Olympus Corp | Telephoto lens and telephoto lens device |
JP2009169051A (en) * | 2008-01-16 | 2009-07-30 | Canon Inc | Zoom lens and imaging apparatus having the same |
WO2013011646A1 (en) * | 2011-07-15 | 2013-01-24 | 富士フイルム株式会社 | Zoom lens and imaging device |
JPWO2013011646A1 (en) * | 2011-07-15 | 2015-02-23 | 富士フイルム株式会社 | Zoom lens and imaging device |
US9075224B2 (en) | 2011-07-15 | 2015-07-07 | Fujifilm Corporation | Zoom lens and imaging apparatus |
JP2017173680A (en) * | 2016-03-25 | 2017-09-28 | キヤノン株式会社 | Zoom lens and image capturing device having the same |
JP2020181157A (en) * | 2019-04-26 | 2020-11-05 | キヤノン株式会社 | Lens device, image capturing device, correction method, and program |
US11573410B2 (en) | 2019-04-26 | 2023-02-07 | Canon Kabushiki Kaisha | Lens apparatus, image pickup apparatus, method of correcting change in focal position, and storage medium |
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