JPH0453915A - Zoom lens - Google Patents
Zoom lensInfo
- Publication number
- JPH0453915A JPH0453915A JP16468290A JP16468290A JPH0453915A JP H0453915 A JPH0453915 A JP H0453915A JP 16468290 A JP16468290 A JP 16468290A JP 16468290 A JP16468290 A JP 16468290A JP H0453915 A JPH0453915 A JP H0453915A
- Authority
- JP
- Japan
- Prior art keywords
- lens group
- lens
- focal length
- negative
- refractive power
- 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
Links
- 230000007423 decrease Effects 0.000 claims description 3
- 230000003247 decreasing effect Effects 0.000 abstract 1
- 230000004075 alteration Effects 0.000 description 10
- 206010010071 Coma Diseases 0.000 description 2
- 201000009310 astigmatism Diseases 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 241001057181 Orcus Species 0.000 description 1
- 238000009412 basement excavation Methods 0.000 description 1
- 239000000470 constituent Substances 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 230000005499 meniscus Effects 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
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- Lenses (AREA)
Abstract
Description
【発明の詳細な説明】
本発明はコンパクトなズームレンズに関するものである
。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a compact zoom lens.
さらに本発明は、コンパクトな望遠ズームレンズであり
ながらズーミングに際し、比較的簡単な移動形式で、か
つ簡単な構成のズームレンズに関するものである。Furthermore, the present invention relates to a compact telephoto zoom lens that is relatively easy to move during zooming and has a simple configuration.
従来の４成分型望遠ズームレンズは、フォーカシング群
である。第１正レンズ群、バリエーター群である第２負
レンズ群、コンペンセーター群であるｖＩ３Ｉ３正レン
ズ群びマスターレンズ群であるｗＩ４正レンズ群より構
成される。第１正レンズ群と第４正レンズ群がズーミン
グ時固定されており、バリエータ−群である第２負レン
ズ群を光軸上で移動させることにより変倍を行い、変倍
の際に生じる像点の補正はコンペンセータ群である第の
ズームレンズ系においては、各群に比較的強い屈折力を
持つレンズ群を有するので、各群の構成要素があまり簡
単にならないという欠点があった。A conventional four-component telephoto zoom lens has a focusing group. It is composed of a first positive lens group, a second negative lens group which is a variator group, a vI3I3 positive lens group which is a compensator group, and a wI4 positive lens group which is a master lens group. The first positive lens group and the fourth positive lens group are fixed during zooming, and the magnification is changed by moving the second negative lens group, which is a variator group, on the optical axis. In the first zoom lens system in which the point correction is performed by a compensator group, each group has a lens group having a relatively strong refractive power, so there is a drawback that the constituent elements of each group are not very simple.
本発明は、以上のような問題を克服したコンパクトなズ
ームレンズを提供することを目的とする。An object of the present invention is to provide a compact zoom lens that overcomes the above problems.
本発明のズームレンズは、物体側がら順に正の屈折力を
有する第１レンズ群（１）、負の屈折力を有する第２レ
ンズ群（■）、正の屈折力を有する第３レンズ群（［１
）、及び負の屈折力を有する第４レンズ群（ＩＶ）から
成り、最短焦点距離状態がら最長焦点距離状態へのズー
ミングに際し、第１レンズ群は像面に対して固定され、
第１レンズ群と第２レンズ群との間隔が増大し、第３レ
ンズ群と第４レンズ群との間隔が減少するような動きを
し、近接撮影をする時には第２レンズ群が像面側へ移動
することを特徴とする。The zoom lens of the present invention includes, in order from the object side, a first lens group (1) having a positive refractive power, a second lens group (■) having a negative refractive power, and a third lens group (■) having a positive refractive power. [1
), and a fourth lens group (IV) having negative refractive power, and when zooming from the shortest focal length state to the longest focal length state, the first lens group is fixed with respect to the image plane,
The distance between the first lens group and the second lens group increases, and the distance between the third lens group and the fourth lens group decreases, and when close-up photography is performed, the second lens group moves toward the image plane. It is characterized by moving to.
以上のような構成及び移動形式により本発明の＄１の目
的であるコンパクトなズームレンズが実現できる。With the above-described configuration and movement type, a compact zoom lens, which is the object of the first aspect of the present invention, can be realized.
さらには、本発明では上記のような正・負・正・負の４
＃構成のズームレンズの第１レンズ群のみがズーミング
及びフォーカシングに際し、像面に対し固定され、第２
レンズ群、第３レンズ群、第４レンズ群の各群がそれぞ
れに移動するという構成を特徴としている。第１レンズ
群が固定されているということは次のようなメリットが
ある。例えば、水中撮影の際に、望遠ズームレンズにお
いＩす１
て、重←位置が大きく変動するものは使用しがたく、径
の最も大きい第１レンズ群暮ズーミング時固定されるこ
とが望ましい。さらに、外部からの衝撃に対しては、大
きな径の第１レンズ群が受ける衝撃は他のレンズ群に比
べ当然大きく、＠ｌレンズ群を固定にすることでその衝
撃を小さくすることが出来る。又、ズームレンズのフォ
ーカシングは変倍に際して固定している第１レンズ群の
繰り出しによって行われるのが一般的である。しかし、
オート７オーカスシステムを考えた場合、レンズ口径が
大きく重いｗｌルンズ群を繰り出す方式は好ましくない
。さらに、レンズにフィルターやフード等のアクセサリ
−が取付けられている時には、そのアクセサリ−をも７
オ一カシング時に動かす必要があるため、適当ではない
。Furthermore, in the present invention, the above-mentioned positive, negative, positive, and negative four
Only the first lens group of the zoom lens with # configuration is fixed to the image plane during zooming and focusing, and the second lens group is fixed to the image plane during zooming and focusing.
It is characterized by a configuration in which each of the lens groups, the third lens group, and the fourth lens group moves individually. The fact that the first lens group is fixed has the following advantages. For example, when photographing underwater, it is difficult to use a telephoto zoom lens whose weight and position vary greatly, and it is desirable that the first lens group, which has the largest diameter, be fixed during zooming. Furthermore, in response to an external impact, the first lens group having a large diameter naturally receives a larger impact than the other lens groups, and by fixing the @l lens group, the impact can be reduced. Further, focusing of a zoom lens is generally performed by extending a fixed first lens group during zooming. but,
When considering the Auto 7 Orcus system, it is not preferable to use a system that uses a large lens aperture and a heavy wl lens group. Furthermore, if accessories such as filters and hoods are attached to the lens, the accessories may also be removed.
It is not suitable because it needs to be moved during excavation.
そこで本発明では第１レンズ群に比べ構成が簡単で軽量
の第２レンズ群により妙７オーカシングを行うものであ
る。フォーカシング用レンズがカメラの本体側にあると
いうことは、７オーカシング用レンズがカメラ本体内部
のモーター等の駆動力源に近く駆動が簡単となることを
意味する。又、７オーカシング用レンズが軽いというこ
とは比較的弱い駆動力で迅速なフォーカシング調節が可
能となることを意味する。Therefore, in the present invention, the second lens group is simpler in construction and lighter in weight than the first lens group to perform the 7-point focusing. The fact that the focusing lens is located on the side of the camera body means that the focusing lens is close to a driving power source such as a motor inside the camera body and can be easily driven. Furthermore, the fact that the 7 focusing lens is lightweight means that rapid focusing adjustment is possible with a relatively weak driving force.
以上のようなレンズ構成、移動形式に加えて、次槽よう
な条件式を満足することが望ましい。In addition to the above-mentioned lens configuration and movement type, it is desirable to satisfy the following conditional expression.
ｂ
０．５３ ＜ −＜ ０．６２ ・・・・
・・ （２）Ｌ
ｆ！
０．８８ ＜ −＜ ０．９６ ・・・・・・（３）
ｆ。b 0.53 <−< 0.62 ・・・・
... (2) L f! 0.88 <-< 0.96 (3)
f.
但し、ｆｗ二最短焦点距離状態での全系の焦点距離ｆＬ
：最長焦点距離状態での全系の焦点距離ｆ１：第１レン
ズ群の焦点距離
ｆ２：第２レンズ群の焦点距離
ｆ４：第４レンズ群の焦点距離
条件式（１）は、上述したような正・負・正・負の４群
構成で一定の焦点距離ｆｗを確保するために第４負レン
ズ群の屈折力を規定する条件である。However, the focal length fL of the entire system in the shortest focal length state
: Focal length of the entire system in the longest focal length state f1: Focal length of the first lens group f2: Focal length of the second lens group f4: Focal length of the fourth lens group Conditional expression (1) is as described above. This is a condition that defines the refractive power of the fourth negative lens group in order to ensure a constant focal length fw with a positive, negative, positive, and negative four group configuration.
下限を越えて第４レンズ群の負屈折力が弱くなると、全
系の屈折力のバランスをとるために他のレンズ群の屈折
力も弱くせざるをえない。従って変倍時の移動量が増加
し、最短距離状態でのレンズの全長が長くなり、コンパ
クトなレンズを達成できなくなる。一方、その上限を越
えると変倍中の収差変動、特ｊ二非点収差の変動と球面
収差の変動をバランズ良く補正することが困難となる。If the lower limit is exceeded and the negative refractive power of the fourth lens group becomes weak, the refractive powers of the other lens groups must also be weakened in order to balance the refractive power of the entire system. Therefore, the amount of movement during zooming increases, and the total length of the lens in the shortest distance state becomes longer, making it impossible to achieve a compact lens. On the other hand, if the upper limit is exceeded, it becomes difficult to correct aberration fluctuations during zooming, especially fluctuations in astigmatism and spherical aberration, in a well-balanced manner.
条件式（２）は第２負レンズ群の屈折力を規定し、第２
負レンズ群の変倍効果を適性にすることによりレンズ全
系のコンパクト化を図る為のものである。条件（２）の
下限を越えると、第２負レンズ群の変倍効果が減少する
ため、所定の変倍比を得るために第３正レンズ群の移動
量を大きくしなければならず全長が長くなりコンパクト
化に反する。Conditional expression (2) defines the refractive power of the second negative lens group, and
This is to make the entire lens system more compact by optimizing the variable power effect of the negative lens group. If the lower limit of condition (2) is exceeded, the zooming effect of the second negative lens group decreases, and the amount of movement of the third positive lens group must be increased in order to obtain a predetermined zoom ratio, resulting in a reduction in overall length. It becomes long and goes against the idea of compactness.
一方、条件（２）の上限を越えるとレンズ全長は短り、
コマ収差、非点収差のズーム変動を補正するのが困難と
なる。On the other hand, when the upper limit of condition (2) is exceeded, the total lens length becomes shorter,
It becomes difficult to correct zoom fluctuations such as coma aberration and astigmatism.
条件式（３）は、第１正レンズ群と第２負レンズ群の屈
折力を規定するもので、上限を越えると第五
２負レンズ群の屈折力が弱まる方向になり前妻径の増大
に結びつきコンパクト化が達成できない。Conditional expression (3) defines the refractive power of the first positive lens group and the second negative lens group, and if the upper limit is exceeded, the refractive power of the 52nd negative lens group will weaken, leading to an increase in the front diameter. Connection and compactness cannot be achieved.
ス、下限を越えて第２負レンズ群の屈折力が強まる方向
になると、コマ収差、歪曲収差の補正が困難になる。又
、第１正レンズ群の屈折力が弱まるため、全系として屈
折力のバランスをとるために他のレンズ群の屈折力も弱
くしなければならず、ズーミング時の各レンズ群の移動
量が増大し、コンパクト化に反する。If the lower limit is exceeded and the refractive power of the second negative lens group becomes stronger, it becomes difficult to correct coma and distortion. Additionally, since the refractive power of the first positive lens group is weakened, the refractive power of the other lens groups must also be weakened in order to balance the refractive power of the entire system, which increases the amount of movement of each lens group during zooming. This is contrary to compactness.
条件式（４）は第２ルンズ群の焦点距離に対する第４負
レンズ群の屈折力に関し、主に全系の焦点距離をｔＩＩ
節し、全体の収差をバランス良く補正するためのもので
ある。下限を越えて第４レンズ群の屈折力が強くなりす
ぎると、それに伴い第３レンズ群の屈折力を強めなけれ
ばならず、この結果変倍に伴う収差変動が多くなってく
るので良くない。一方、上限を越えて第４レンズ群の屈
折力が弱くなってくると、諸収差をバランス良く補正す
るのが困難となってくる。Conditional expression (4) relates to the refractive power of the fourth negative lens group with respect to the focal length of the second lens group, and mainly refers to the focal length of the entire system as tII.
This is to correct overall aberrations in a well-balanced manner. If the lower limit is exceeded and the refractive power of the fourth lens group becomes too strong, the refractive power of the third lens group must be strengthened accordingly, and as a result, aberration fluctuations due to zooming increase, which is not good. On the other hand, when the upper limit is exceeded and the refractive power of the fourth lens group becomes weak, it becomes difficult to correct various aberrations in a well-balanced manner.
さらに本発明のズームレンズは、第１１７１群は少なく
とも物体側に凸面を向けた負レンズを有し、第２レンズ
群は少なくとも１枚の負レンズ及び正レンズを有し、第
３レンズ群は少なくとも１枚の正レンズを含む３枚のレ
ンズから成り、第４レンズ群は最も物体側に１枚の負メ
ニスカスレンズを有するような構成とするのが望ましい
。Further, in the zoom lens of the present invention, the 1171st lens group includes at least a negative lens with a convex surface facing the object side, the second lens group includes at least one negative lens and a positive lens, and the third lens group includes at least one negative lens and a positive lens. It is desirable that the fourth lens group is composed of three lenses including one positive lens, and has one negative meniscus lens closest to the object side.
以上の条件を満足することにより、コンパクトな望遠ズ
ームレンズでありながら、ズーミングに際し比較的簡単
な移動方式で、かつ、簡単な＊成のズームレンズを提供
することができる。By satisfying the above conditions, it is possible to provide a telephoto zoom lens that is compact, has a relatively simple movement method during zooming, and has a simple configuration.
以下、本発明の実施例１〜３をそれぞれ表１〜３に示す
。Examples 1 to 3 of the present invention are shown in Tables 1 to 3, respectively.
但し、ｆ：全系の焦点距離、
Ｆ：開放Ｆナンバー
ｒｌ（ｉ＝１．２．３． ・・・）：物体側から第１
番目のレンズ面の曲率半径、
ｄ、（ｉ−１，２，３，・・・）：物体側から第１番目
の軸上面間隔、
ら第１番目のレンズのｄ線に対する屈折率、ν、（ｉ＝
１．２．３． ・・・）：物体側から第１番目のレン
ズのアツベ数、
である。However, f: focal length of the entire system, F: open F number rl (i = 1.2.3...): first from the object side.
Radius of curvature of the 1st lens surface, d, (i-1, 2, 3,...): Distance between the 1st axial surfaces from the object side, and the refractive index of the 1st lens with respect to the d line, ν, (i=
1.2.3. ): Atsube number of the first lens from the object side.
また、各実施例と各条件との関係を表４に示す。Further, Table 4 shows the relationship between each example and each condition.
（１ｘＴ体６） Ｎ、（ｉ＝１．２，３． ・・・）：物体側か表 〈実施例１〉 ｆ −１０′Ｌ０−１５０．０−１９５．０Ｆ−４，６ 曲率半径 軸上面間隔 屈折率（Ｎｄ） アツベ数（νｄ） 表 〈実施例３〉 ｆ −１０２，０−１５０，０−１９５，０Ｆ−４，６ 曲率半径 軸上面間隔 屈折率（Ｎｄ） アツベ数（しｄ） 表 〈実施例２〉 １−１０２．０〜１５０．０−１９５．０曲率半径 軸」−面間隔 屈υ１率（Ｎｄ１ ７ツベ数（νｄ） ｒ＋ １４５．８３５ ｄｌ。(1xT body 6) N, (i=1.2,3....): Object side or front <Example 1> f -10'L0-150.0-195.0F-4,6 curvature radius Shaft top surface spacing Refractive index (Nd) Atsbe number (νd) table <Example 3> f-102, 0-150, 0-195, 0F-4, 6 curvature radius Shaft top surface spacing Refractive index (Nd) Atsbe number (shid) table <Example 2> 1-102.0~150.0-195.0 radius of curvature Axis”-plane distance Refractive modulus (Nd1 7 tube number (νd) r+ 145.835 dl.
１８０゜ Ｎ。180° N.
１、７５４５０
し。５１５７
表
なお、第１〜３図はそれぞれ本発明の実施例１〜３の最
短焦点距離状態＜Ｗ＞における各レンズ群の配置を示す
レンズ断面図である。下方に示す実線は、最長焦点距離
状態＜Ｔ＞へのレンズ群移動形式を示す。また破線はそ
のレンズ群がズーミング中移動しないことを示す。但し
、ここで、（１）は第１レンズ群、（ＩＩ）は第２レン
ズ群、（Ｉ［［）は第３レンズ群、（ＩＶ）は第４レン
ズ群である。1,75450. 5157 Table Note that FIGS. 1 to 3 are lens sectional views showing the arrangement of each lens group in the shortest focal length state <W> of Examples 1 to 3 of the present invention, respectively. The solid line shown below indicates the lens group movement form to the longest focal length state <T>. Moreover, the broken line indicates that the lens group does not move during zooming. However, here, (1) is the first lens group, (II) is the second lens group, (I[[) is the third lens group, and (IV) is the fourth lens group.
第４〜６図はそれぞれ、本発明実施例１〜３の最短焦点
距離状態＜Ｗ＞、中間焦点距離状態くＭ〉及び最長焦点
距離状態＜Ｔ＞の各収差を示す収差図である。但し、こ
こで、Ｆは開放Ｆナンバーωは半画角である。4 to 6 are aberration diagrams showing aberrations in the shortest focal length state <W>, intermediate focal length state M>, and longest focal length state <T> of Examples 1 to 3 of the present invention, respectively. However, here, F is the open F-number ω is the half angle of view.
第１〜３図はそれぞれ本発明実施例１〜３の最短焦点距
離状態における各レンズ群の配置を示すレンズ断面図、
第４〜６図はそれぞれ本発明実施例１〜３の最短焦点距
離状態、中間焦点距離状態及び最長焦点距離状態の各収
差を示す収差図である。
（Ｉ）：第１レンズ群、
（■）：第２レンズ群、
（■）：第３レンズ群、
（■）：第４レンズ群。1 to 3 are lens sectional views showing the arrangement of each lens group in the shortest focal length state of Examples 1 to 3 of the present invention, respectively;
4 to 6 are aberration diagrams showing aberrations in the shortest focal length state, intermediate focal length state, and longest focal length state of Examples 1 to 3 of the present invention, respectively. (I): 1st lens group, (■): 2nd lens group, (■): 3rd lens group, (■): 4th lens group.
Claims (1)
、負の屈折力を有する第２レンズ群、正の屈折力を有す
る第３レンズ群及び負の屈折力を有する第４レンズ群か
ら成り、最短焦点距離状態から最長焦点距離状態へのズ
ーミングに際し、第１レンズ群は像面に対して固定され
、第１レンズ群と第２レンズ群との間隔が増大し、第３
レンズ群と第４レンズ群との間隔が減少するような動き
をし、近接撮影をする時には第２レンズ群が像面側へ移
動することを特徴とするコンパクトなズームレンズ。 （２）以下の条件を満足することを特徴とする特許請求
の範囲 第１項記載のズームレンズ。 ２＜（ｆ＿ｗ）／（｜ｆ＿４｜）＜２．３ ０．５３＜（｜ｆ＿２｜）／（ｆ＿Ｌ）＜０．６２０．
８８＜（｜ｆ＿２｜）／（ｆ＿１）＜０．９６０．３５
＜（ｆ＿４）／（ｆ＿２）＜０．４５但し、ｆ＿ｗ：最
短焦点距離状態での全系焦点距離ｆ＿Ｌ：最長焦点距離
状態での全系焦点距離ｆ＿１：第１レンズ群の焦点距離 ｆ＿２：第２レンズ群の焦点距離 ｆ＿４：第４レンズ群の焦点距離[Claims] (1) In order from the object 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 refractive power. When zooming from the shortest focal length state to the longest focal length state, the first lens group is fixed with respect to the image plane, and the distance between the first lens group and the second lens group increases. And the third
A compact zoom lens that moves so that the distance between the lens group and the fourth lens group decreases, and that the second lens group moves toward the image plane side when close-up photography is performed. (2) A zoom lens according to claim 1, which satisfies the following conditions. 2<(f_w)/(|f_4|)<2.3 0.53<(|f_2|)/(f_L)<0.620.
88<(|f_2|)/(f_1)<0.960.35
<(f_4)/(f_2)<0.45 However, f_w: Entire system focal length in the shortest focal length state f_L: Entire system focal length in the longest focal length state f_1: Focal length of the first lens group f_2: The focal length of the first lens group Focal length of 2nd lens group f_4: Focal length of 4th lens group
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16468290A JPH0453915A (en) | 1990-06-22 | 1990-06-22 | Zoom lens |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16468290A JPH0453915A (en) | 1990-06-22 | 1990-06-22 | Zoom lens |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0453915A true JPH0453915A (en) | 1992-02-21 |
Family
ID=15797853
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP16468290A Pending JPH0453915A (en) | 1990-06-22 | 1990-06-22 | Zoom lens |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0453915A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011197413A (en) * | 2010-03-19 | 2011-10-06 | Nikon Corp | Photographic lens, optical apparatus having the photographic lens, and method for manufacturing the photographic lens |
| JP2016151663A (en) * | 2015-02-17 | 2016-08-22 | 株式会社タムロン | Optical system, and image pickup apparatus |
-
1990
- 1990-06-22 JP JP16468290A patent/JPH0453915A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011197413A (en) * | 2010-03-19 | 2011-10-06 | Nikon Corp | Photographic lens, optical apparatus having the photographic lens, and method for manufacturing the photographic lens |
| JP2016151663A (en) * | 2015-02-17 | 2016-08-22 | 株式会社タムロン | Optical system, and image pickup apparatus |
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