JPH07311351A - Wide angle eyepiece system - Google Patents

Wide angle eyepiece system

Info

Publication number
JPH07311351A
JPH07311351A JP6124704A JP12470494A JPH07311351A JP H07311351 A JPH07311351 A JP H07311351A JP 6124704 A JP6124704 A JP 6124704A JP 12470494 A JP12470494 A JP 12470494A JP H07311351 A JPH07311351 A JP H07311351A
Authority
JP
Japan
Prior art keywords
lens
group
positive power
order
aspherical
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
Application number
JP6124704A
Other languages
Japanese (ja)
Inventor
Kazuyoshi Yokoo
和良 横尾
Hiroyuki Furuta
博之 古田
Shoichi Takei
正一 武井
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
KIYOUSERA OPT KK
Original Assignee
KIYOUSERA OPT KK
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by KIYOUSERA OPT KK filed Critical KIYOUSERA OPT KK
Priority to JP6124704A priority Critical patent/JPH07311351A/en
Publication of JPH07311351A publication Critical patent/JPH07311351A/en
Pending legal-status Critical Current

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Abstract

PURPOSE:To make a wide angle eyepiece system have a minimal number of lenses and have a wide angle of view and have well compensated astigmatic aberration. CONSTITUTION:The wide angle eyepiece system is composed of three-group four lenses, in order from an eye-point E. P to an objective lens, a lens group L1 having a positive power composed of an aspherical surface and a spherical surface, a lens group L2 having a positive power composed of the combined lens of a meniscus lens and a bi-convex lens, a lens group L3 having a positive power composed of a meniscus lens are arranged. R1 and R2 are the radii of curvature of the lens group L1 in order from the position close to the eye point E. P, R3-$5 are the radii of curvature of the lens group L2 in order from the position close to the eye point E. P and R6, R7 are the radii of curvature of the lens group L3 in order from the position close to the eye point E. P.

Description

【発明の詳細な説明】Detailed Description of the Invention

【0001】[0001]

【産業上の利用分野】本発明は、接眼レンズ系の内、特
に双眼鏡または望遠鏡その他に利用される非球面形状の
レンズを有する広角の接眼レンズ系に関するものであ
る。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wide-angle eyepiece system having an aspherical lens for use in binoculars, telescopes and the like, among eyepiece lens systems.

【0002】[0002]

【従来の技術】広角の接眼レンズ系にあっても、他のレ
ンズ系と同様に構成レンズの一部に非球面形状のものを
用いることによりレンズ枚数の減少およびコンパクト化
などを図るようにしたものがある。
2. Description of the Related Art Even in a wide-angle eyepiece system, the number of lenses and the size thereof can be reduced by using aspherical lenses as a part of the constituent lenses, as in other lens systems. There is something.

【0003】[0003]

【発明が解決しようとする課題】しかしながら、このよ
うな、非球面形状のレンズを一部に採用した広角の接眼
レンズにあっては、レンズ本来の収差補正と瞳の収差補
正とを同時に行なわなくてはならないため、ここでもレ
ンズの枚数の増加を招き、レンズ枚数を1枚でも少なく
する場合には接眼レンズの画角を狭く制限して収差補正
を行なわなくてはならないという欠点を有していた。例
えば、双眼鏡に用いる画角60度程度の広角の接眼レン
ズについては、非球面形状のレンズを用いてレンズ枚数
を少なくしようとしても非点隔差を小さくすることがで
きなかった。
However, in such a wide-angle eyepiece lens partly employing an aspherical lens, the original aberration correction of the lens and the pupil aberration correction are not performed at the same time. This also causes an increase in the number of lenses, and has the drawback that when the number of lenses is reduced by one, aberrations must be corrected by limiting the angle of view of the eyepiece. It was For example, with respect to a wide-angle eyepiece lens having an angle of view of about 60 degrees used for binoculars, even if an aspherical lens is used to reduce the number of lenses, the astigmatic difference cannot be reduced.

【0004】本発明の目的は、上記従来技術の欠点を解
消するため、最小のレンズ枚数で構成し、かつ、広い画
角で非点隔差が良好に補正された広角の接眼レンズ系を
提供することにある。
An object of the present invention is to provide a wide-angle eyepiece system which is constructed with a minimum number of lenses and has a wide angle of view and in which the astigmatic difference is well corrected in order to solve the above-mentioned drawbacks of the prior art. Especially.

【0005】[0005]

【課題を解決するための手段】この目的は、本発明の要
部である、レンズ構成が3群4枚からなる広角の接眼レ
ンズ系において、アイポイントから対物側の方向に順
に、前記第1群が正のパワーを持つ単レンズ、前記第2
群が正のパワーを持つ貼合わせレンズ、前記第3群が正
のパワーを持つ単レンズ、とで構成することにより、達
成される。以上の構成において、非球面形状のレンズを
採用する場合に次の態様が好ましい。第1に、前記1群
の単レンズはアイポイント側または対物側の何れか1面
が非球面形状で構成する。第2に、前記2群の貼合わせ
レンズはメニスカスレンズおよび球面と非球面形状とか
らなるレンズで構成する。第3に、前記2群の貼合わせ
レンズはメニスカスレンズおよび球面と非球面形状とか
らなるレンズで構成すると共に、前記3群の単レンズは
アイポイント側または対物側の何れか1面が非球面形状
で構成することである。
This object is a main part of the present invention, and in a wide-angle eyepiece lens system having a lens configuration of 4 elements in 3 groups, the first element is arranged in order from the eyepoint to the objective side. A single lens whose group has a positive power, the second lens
This is achieved by constructing a cemented lens of which the group has a positive power, and a third lens of which the third group has a positive power. In the above configuration, the following modes are preferable when an aspherical lens is adopted. First, the single lens of the first group is constructed such that either the eyepoint side or the object side has an aspherical surface. Secondly, the cemented lens of the second group is composed of a meniscus lens and a lens having a spherical surface and an aspherical shape. Thirdly, the cemented lens of the second group is composed of a meniscus lens and a lens having a spherical surface and an aspherical shape, and the single lens of the third group has an aspherical surface on either the eyepoint side or the objective side. It is to be configured with a shape.

【0006】[0006]

【作用】以上の本発明で特定される広角の接眼レンズ系
によれば、レンズ構成が3群4枚という少ない枚数であ
りながら、広角にて非点隔差を良好に補正することがで
きた。また、非球面形状のレンズを採用する場合にコス
ト高にならないように最小限にとどめることが不可欠で
あるが、本発明のレンズ構成は前記態様特定により非点
隔差の補正を経済的に行なうことを可能にする。
According to the wide-angle eyepiece lens system specified by the present invention as described above, the astigmatic difference can be satisfactorily corrected in the wide-angle range even though the number of lenses is as small as 4 in 3 groups. Further, when an aspherical lens is adopted, it is indispensable to minimize the cost so as not to increase the cost, but the lens configuration of the present invention economically corrects the astigmatic difference by specifying the above-mentioned aspect. To enable.

【0007】[0007]

【実施例】以下、本発明の実施例について図面を参照し
つつ説明する。この実施例においては、アイポイントに
近いレンズ面から順に面番号をi面(i=1,2,3・・・)と
して表すと共に、光学系を表すバラメータを次のように
定義する。faは接眼レンズ全体の焦点距離(mm)で
ある。Riは第i面の曲率半径(mm)である。但し、
非球面の場合は非球面の頂点における曲率半径とする。
iは第i面と第(i+1)面との光軸上の面間隔(m
m)である。niは第i面と第(i+1)面との間の媒質
のd線の屈折率である。但し、空気の屈折率曲niは空
欄とする。νdiは第i面と第(i+1)面との間の媒質
のd線のアッベ数である。但し、空気のアッベ数は空欄
とする。
Embodiments of the present invention will be described below with reference to the drawings. In this embodiment, the surface number is represented as the i-plane (i = 1, 2, 3, ...) In order from the lens surface close to the eye point, and the parameter representing the optical system is defined as follows. f a is the focal length of the entire eyepiece (mm). R i is the radius of curvature (mm) of the i-th surface. However,
In the case of an aspherical surface, it is the radius of curvature at the apex of the aspherical surface.
d i is the surface interval on the optical axis between the i-th surface and the (i + 1) surface (m
m). ni is the d-line refractive index of the medium between the i-th surface and the (i + 1) -th surface. However, the refractive index curve n i of air is blank. ν di is the Abbe number of the d line of the medium between the i-th surface and the (i + 1) -th surface. However, the Abbe number of air should be blank.

【0008】また、以下の実施例では非球面形状を次の
関数で表す。 x=(H2/R)/ {(1+(1−A(H/
R)21/2} ここで、各パラメータは次のように定義される。xは非
球面の頂点の接平面からその非球面上の高さHの点まで
の距離である。Hは光軸からの高さである。Rは非球面
頂点における曲率である。Aは円錐定数である。
In the following embodiments, the aspherical surface shape is expressed by the following function. x = (H 2 / R) / {(1+ (1-A (H /
R) 2 ) 1/2 } Here, each parameter is defined as follows. x is the distance from the tangent plane of the vertex of the aspherical surface to the point of height H on the aspherical surface. H is the height from the optical axis. R is the curvature at the aspherical vertex. A is a conic constant.

【0009】次に、実施例1から5の光学系の基本構成
を示す。(この数値構成に基づいて各実施例の最適な円
錐定数Aが決められる。) fa=1.0 i Rii νdii 1 -2.642 0.205 64.2 1.51680 2 -0.759 0.005 3 3.523 0.062 25.5 1.80518 4 1.233 0.446 64.2 1.51680 5 -1.521 0.281 6 1.027 0.214 64.2 1.51680 7 2.188
Next, the basic structure of the optical system of Examples 1 to 5 will be shown. (Optimum conic constant A of each example on the basis of the numerical arrangement can be determined.) F a = 1.0 i R i d i ν di n i 1 -2.642 0.205 64.2 1.51680 2 -0.759 0.005 3 3.523 0.062 25.5 1.80518 4 1.233 0.446 64.2 1.51680 5 -1.521 0.281 6 1.027 0.214 64.2 1.51680 7 2.188

【0010】図1は実施例1から5におけるレンズ構成
の配置を総括的に示している。この広角接眼レンズ系
は、何れの実施例でもレンズ構成が3群4枚からなり、
アイポイントE.Pから対物レンズの方向に順に、正の
パワーを持つレンズ群L1、貼合わせレンズで正のパワ
ーを持つレンズ群L2、単レンズで正のパワーを持つレ
ンズ群L3とを配置したものである。図中、R1,R2は
アイポイントE.Pに近い順にレンズ群L1の曲率半径
を示す。R3,R4,R5はアイポイントE.Pに近い順
にレンズ群L2の曲率半径を示す。R6,R7はアイポイ
ントE.Pに近い順にレンズ群L3の曲率半径を示す。
d1はレンズ群L1における1面と2面との光軸上の面間隔
(1番レンズの厚さ)を示す。d2はレンズ群L1の2面
とレンズ群L2の3面との光軸上の面間隔(1番レンズと
2番レンズとの空気間隔)を示す。d3はレンズ群L2に
おける3面と4面との光軸上の面間隔(2番レンズの厚
さ)を示す。d4はレンズ群L2における4面と5面との光
軸上の面間隔(3番レンズの厚さ)を示す。d5はレン
ズ群L2の5面とレンズ群L3の6面との光軸上の面間隔
(3番レンズと4番レンズとの空気間隔)を示す。d6
はレンズ群L3における1面と2面との光軸上の面間隔
(4番レンズの厚さ)を示す。
FIG. 1 generally shows the arrangement of lens configurations in Examples 1 to 5. This wide-angle eyepiece lens system has a lens configuration of 4 elements in 3 groups in any of the examples,
Eyepoint E. A lens group L1 having a positive power, a lens group L2 having a positive power as a cemented lens, and a lens group L3 having a positive power as a single lens are arranged in this order from P to the objective lens. In the figure, R1 and R2 are eye points E.I. The radii of curvature of the lens unit L1 are shown in the order closer to P. R3, R4, R5 are eye points E. The radii of curvature of the lens unit L2 are shown in the order closer to P. R6 and R7 are eye points E. The radii of curvature of the lens unit L3 are shown in the order closer to P.
d1 indicates the surface distance (thickness of the first lens) on the optical axis between the first surface and the second surface in the lens unit L1. d2 represents the surface distance (the air distance between the first lens and the second lens) on the optical axis between the two surfaces of the lens unit L1 and the three surfaces of the lens unit L2. d3 represents the surface distance (thickness of the second lens) on the optical axis between the third surface and the fourth surface in the lens unit L2. d4 represents the surface distance (thickness of the third lens) on the optical axis between the fourth surface and the fifth surface in the lens unit L2. d5 represents the surface distance on the optical axis between the fifth surface of the lens unit L2 and the sixth surface of the lens unit L3 (air distance between the third lens and the fourth lens). d6
Indicates the surface distance (thickness of the 4th lens) on the optical axis between the first surface and the second surface in the lens unit L3.

【0011】(第1実施例のレンズ構成)アイポイント
E.Pから対物レンズの方向に順に、非球面と球面から
なる正のパワーを持つレンズ群L1、メニスカスレンズ
と両凸レンズとの貼合わせレンズからなる正のパワーを
持つレンズ群L2、メニスカスレンズからなる正のパワ
ーを持つレンズ群L3を配置して構成した。上記光学系
の数値構成を前提とし、Aの最適値は A=−10.0 である。この実施例のレンズ構成では非点収差が図2の
ようになる。
(Lens Construction of First Embodiment) Eyepoint E.I. In order from P to the direction of the objective lens, a lens group L1 composed of an aspherical surface and a spherical surface having a positive power, a lens group L2 composed of a cemented lens of a meniscus lens and a biconvex lens, and a positive lens composed of a meniscus lens. The lens unit L3 having the power of is arranged. Given the numerical configuration of the above optical system, the optimum value of A is A = -10.0. Astigmatism in the lens configuration of this embodiment is as shown in FIG.

【0012】(第2実施例のレンズ構成)アイポイント
E.Pから対物レンズの方向に順に、球面と非球面から
なる正のパワーを持つレンズ群L1、メニスカスレンズ
と両凸レンズとの貼合わせレンズからなる正のパワーを
持つレンズ群L2、およびメニスカスレンズからなる正
のパワーを持つレンズ群L3を配置して構成した。上記
光学系の数値構成を前提とし、Aの最適値は A=1.1 である。そして、この実施例のレンズ構成では非点収差
が図3のようになる。
(Lens Construction of Second Embodiment) Eyepoint E.I. In order from P to the direction of the objective lens, a lens unit L1 having a positive power composed of a spherical surface and an aspherical surface, a lens unit L2 having a positive power composed of a cemented lens of a meniscus lens and a biconvex lens, and a meniscus lens. It is configured by arranging a lens unit L3 having a positive power. Assuming the numerical configuration of the above optical system, the optimum value of A is A = 1.1. The astigmatism in the lens structure of this embodiment is as shown in FIG.

【0013】(第3施例のレンズ構成)アイポイント
E.Pから対物レンズの方向に順に、メニスカスレンズ
からなる正のパワーを持つレンズ群L1、メニスカスレ
ンズと球面と非球面からなるレンズとを貼合わせたもの
で正のパワーを持つレンズ群L2、およびメニスカスレ
ンズからなる正のパワーを持つレンズ群L3を配置して
構成した。上記光学系の数値構成を前提とし、Aの最適
値は A=1.7 である。そして、この実施例のレンズ構成では非点収差
が図4のようになる。
(Lens Construction of Third Embodiment) Eyepoint E.I. In order from P to the direction of the objective lens, a lens group L1 composed of a meniscus lens having a positive power, a lens group L2 composed of a meniscus lens and a lens composed of a spherical surface and an aspherical surface having a positive power, and a meniscus. It is configured by arranging a lens unit L3 having a positive power composed of lenses. Given the numerical configuration of the above optical system, the optimum value of A is A = 1.7. The astigmatism in the lens structure of this embodiment is as shown in FIG.

【0014】(第4施例のレンズ構成)アイポイント
E.Pから対物レンズの方向に順に、メニスカスレンズ
からなる正のパワーを持つレンズ群L1、メニスカスレ
ンズと球面と非球面からなるレンズとを貼合わせたもの
で正のパワーを持つレンズ群L2、および非球面と球面
からなる正のパワーを持つレンズ群L3を配置して構成
した。上記光学系の数値構成を前提とし、レンズ群L2
の最適値AをAL2、レンズ群L3の最適値AをAL3とす
ると、 AL2=1.7 AL3=1.1 である。そして、この実施例のレンズ構成では非点収差
が図5のようになる。
(Lens Construction of Fourth Embodiment) Eyepoint E.I. In order from P to the direction of the objective lens, a lens group L1 composed of a meniscus lens having a positive power, a lens group L2 composed of a meniscus lens and a lens composed of a spherical surface and an aspherical surface and having a positive power, and It is configured by arranging a lens group L3 composed of a spherical surface and a spherical surface and having a positive power. Based on the numerical configuration of the above optical system, the lens unit L2
Let AL2 be the optimum value A of AL2 and AL3 be the optimum value A of the lens unit L3, then AL2 = 1.7 AL3 = 1.1. The astigmatism in the lens configuration of this embodiment is as shown in FIG.

【0015】(第5施例のレンズ構成)アイポイント
E.Pから対物レンズの方向に順に、メニスカスレンズ
からなる正のパワーを持つレンズ群L1、メニスカスレ
ンズと球面と非球面からなるレンズとを貼合わせたもの
で正のパワーを持つレンズ群L2、および球面と非球面
からなる正のパワーを持つレンズ群L3を配置して構成
した。上記光学系の数値構成を前提とし、レンズ群L2
の最適値AをAL2、レンズ群L3の最適値AをAL3とす
ると、 AL2=1.7 AL3=−0.10 である。そして、この実施例のレンズ構成では非点収差
が図6のようになり、上記各実施例と同様に優れてい
る。
(Lens Construction of the Fifth Embodiment) Eyepoint E.I. In order from P to the direction of the objective lens, a lens group L1 composed of a meniscus lens having a positive power, a lens group L2 composed of a meniscus lens and a lens composed of a spherical surface and an aspherical surface having a positive power, and a spherical surface. And a lens unit L3 having an aspherical surface and having a positive power are arranged. Based on the numerical configuration of the above optical system, the lens unit L2
Let AL2 be the optimum value A of AL2 and AL3 be the optimum value A of the lens unit L3, then AL2 = 1.7 AL3 = −0.10. The astigmatism in the lens structure of this embodiment is as shown in FIG. 6, which is excellent as in the above-described embodiments.

【0016】[0016]

【発明の効果】以上のように、本発明に係る広角接眼レ
ンズ系は、レンズ構成が3群4枚でありながら、より広
い画角にわたり非点隔差がない接眼レンズを得ることが
でき、これにより双眼鏡や望遠境など精度向上およびコ
ンパクト化に寄与できる。
As described above, in the wide-angle eyepiece system according to the present invention, it is possible to obtain an eyepiece having no astigmatic difference over a wider angle of view even though the lens configuration is four in three groups. This contributes to accuracy improvement and compactness such as binoculars and telephoto.

【図面の簡単な説明】[Brief description of drawings]

【図1】本発明の実施例に係るレンズ構成を総括的に示
す図である。
FIG. 1 is a diagram schematically showing a lens configuration according to an example of the present invention.

【図2】第1実施例に対応する収差曲線図である。FIG. 2 is an aberration curve diagram corresponding to Example 1.

【図3】第2実施例に対応する収差曲線図である。FIG. 3 is an aberration curve diagram corresponding to Example 2.

【図4】第3実施例に対応する収差曲線図である。FIG. 4 is an aberration curve diagram corresponding to Example 3.

【図5】第4実施例に対応する収差曲線図である。FIG. 5 is an aberration curve diagram corresponding to Example 4.

【図6】第5実施例に対応する収差曲線図である。FIG. 6 is an aberration curve diagram corresponding to Example 5.

【符号の説明】[Explanation of symbols]

L1 1群レンズ(正のパワーを持つ単レンズ) L2 2群レンズ(正のパワーを持つ貼合わせレンズ) L3 3群レンズ(正のパワーを持つ単レンズ) L1 1st group lens (single lens with positive power) L2 2nd group lens (bonded lens with positive power) L3 3rd group lens (single lens with positive power)

Claims (4)

【特許請求の範囲】[Claims] 【請求項1】 レンズ構成が3群4枚からなる広角の接
眼レンズ系において、アイポイントから対物側の方向に
順に、前記第1群が正のパワーを持つ単レンズ、前記第
2群が正のパワーを持つ貼合わせレンズ、前記第3群が
正のパワーを持つ単レンズ、とで構成されていることを
特徴とする広角の接眼レンズ系。
1. In a wide-angle eyepiece lens system having three lens groups and four lenses, in order from the eyepoint to the objective side, the first lens group has a positive power, and the second lens group has a positive power. A wide-angle eyepiece lens system, comprising: a cemented lens having a power of, and a third lens having a positive power.
【請求項2】 前記1群の単レンズは、アイポイント側
または対物側の何れか1面が非球面形状である請求項1
に記載の広角の接眼レンズ系。
2. The single lens of the first group has an aspherical surface on either the eyepoint side or the object side.
The wide-angle eyepiece lens system described in.
【請求項3】 前記2群の貼合わせレンズは、メニスカ
スレンズおよび球面と非球面形状とからなるレンズであ
る請求項1に記載の広角の接眼レンズ系。
3. The wide-angle eyepiece system according to claim 1, wherein the cemented lens of the second group is a meniscus lens and a lens having a spherical surface and an aspherical surface.
【請求項4】 前記2群の貼合わせレンズはメニスカス
レンズおよび球面と非球面形状とからなるレンズである
と共に、前記3群の単レンズはアイポイント側または対
物側の何れか1面が非球面形状である請求項1に記載の
広角接眼レンズ系。
4. The cemented lens of the second group is a meniscus lens and a lens having a spherical surface and an aspherical shape, and the single lens of the third group has an aspherical surface on either the eyepoint side or the objective side. The wide-angle eyepiece system according to claim 1, which has a shape.
JP6124704A 1994-05-16 1994-05-16 Wide angle eyepiece system Pending JPH07311351A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP6124704A JPH07311351A (en) 1994-05-16 1994-05-16 Wide angle eyepiece system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP6124704A JPH07311351A (en) 1994-05-16 1994-05-16 Wide angle eyepiece system

Publications (1)

Publication Number Publication Date
JPH07311351A true JPH07311351A (en) 1995-11-28

Family

ID=14892039

Family Applications (1)

Application Number Title Priority Date Filing Date
JP6124704A Pending JPH07311351A (en) 1994-05-16 1994-05-16 Wide angle eyepiece system

Country Status (1)

Country Link
JP (1) JPH07311351A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5850311A (en) * 1995-12-07 1998-12-15 Olympus Optical Co., Ltd. Eyepiece system
CN103823303A (en) * 2014-03-04 2014-05-28 中国科学院光电研究院 Fine Fourier imaging device
WO2014185171A1 (en) * 2013-05-15 2014-11-20 リコーイメージング株式会社 Eyepiece optical system

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5850311A (en) * 1995-12-07 1998-12-15 Olympus Optical Co., Ltd. Eyepiece system
WO2014185171A1 (en) * 2013-05-15 2014-11-20 リコーイメージング株式会社 Eyepiece optical system
JP2014224850A (en) * 2013-05-15 2014-12-04 リコーイメージング株式会社 Eyepiece optical system
US9715085B2 (en) 2013-05-15 2017-07-25 Ricoh Imaging Company, Ltd. Eyepiece optical system
CN103823303A (en) * 2014-03-04 2014-05-28 中国科学院光电研究院 Fine Fourier imaging device
CN103823303B (en) * 2014-03-04 2016-03-09 中国科学院光电研究院 A kind of meticulous Fourier's imaging device

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