JP2902444B2 - Eyepiece - Google Patents
EyepieceInfo
- Publication number
- JP2902444B2 JP2902444B2 JP2104997A JP10499790A JP2902444B2 JP 2902444 B2 JP2902444 B2 JP 2902444B2 JP 2104997 A JP2104997 A JP 2104997A JP 10499790 A JP10499790 A JP 10499790A JP 2902444 B2 JP2902444 B2 JP 2902444B2
- Authority
- JP
- Japan
- Prior art keywords
- lens
- eyepiece
- optical
- resin
- focal length
- 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.)
- Expired - Fee Related
Links
Landscapes
- Lenses (AREA)
Description
【発明の詳細な説明】 「産業上の利用分野」 この発明は、接眼レンズに関するもので、詳しくは双
眼鏡や天体望遠鏡等に用いられる、画角が広く、性能良
好で安価な４枚構成の接眼レンズに関するものである。Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an eyepiece, and more specifically, an inexpensive four-piece eyepiece having a wide angle of view, good performance, and used in binoculars and astronomical telescopes. It is about a lens.
「従来の技術」 画角の広い接眼レンズにおいて、視野の周辺部分まで
十分良好な収差補正を行うために、従来までの接眼レン
ズは、特公昭63−6851号，同60−48014号等のように、
４〜６枚のレンズ構成のものが殆どである。"Conventional technology" For eyepieces with a wide angle of view, conventional eyepieces have been used to correct aberrations sufficiently to the periphery of the field of view, such as Japanese Patent Publication Nos. 63-6851 and 60-48014. To
Most of the lenses have a structure of four to six lenses.
「発明が解決しようとする課題」 しかしながら、４枚を越えるものではコスト高、大型
という課題があり、また４枚構成の接眼レンズで十分良
好な収差補正を得るためには、各レンズの材料に高い屈
折率をもった光学ガラスが必要とされていることと、各
面の曲率半径が小さくなり加工しにくくなることで、コ
スト高になるという課題があった。"Problems to be Solved by the Invention" However, if the number of lenses exceeds four, there is a problem that the cost is large and the size is large. In addition, in order to obtain sufficiently satisfactory aberration correction with the four-piece eyepiece, it is necessary to use materials for each lens. There has been a problem that an optical glass having a high refractive index is required, and a radius of curvature of each surface is reduced to make processing difficult, resulting in an increase in cost.
この発明は、上述の点に鑑みなされたもので、見掛け
視界50゜〜60゜の広視野でも十分良好な収差補正がなさ
れ、また低コストで製作できる接眼レンズを提供するこ
とを目的とする。SUMMARY OF THE INVENTION An object of the present invention is to provide an eyepiece that is sufficiently satisfactory in aberration correction even in a wide visual field having an apparent field of view of 50 to 60 degrees and that can be manufactured at low cost.
「課題を解決するための手段」 この発明の接眼レンズは、眼側から順に、正レンズの
第１レンズと、負メニスカスレンズの第２レンズと、正
レンズの第３レンズと、負レンズの第４レンズとから構
成され、第１レンズと第２レンズは光学ガラスまたは樹
脂製の光学材料からなり、第３レンズと第４レンズは樹
脂製の光学材料からなり、そのなかの少なくとも１面が で表わされる非球面であることを特徴とする。[Means for Solving the Problems] The eyepiece of the present invention comprises, in order from the eye side, a first lens of a positive lens, a second lens of a negative meniscus lens, a third lens of a positive lens, and a third lens of a negative lens. The first lens and the second lens are made of an optical material made of optical glass or resin, and the third lens and the fourth lens are made of an optical material made of resin. Is characterized by an aspheric surface represented by
ここで、Ｘはレンズ頂点から光軸方向への偏移量,yは
レンズ頂点から光軸に垂直な方向への偏移量,Cは曲率半
径の逆数,Kは円錐定数,A4A6……は非球面係数を示す。Here, X is the amount of deviation from the lens vertex in the direction of the optical axis, y is the amount of deviation from the lens vertex in the direction perpendicular to the optical axis, C is the reciprocal of the radius of curvature, K is the conic constant, A 4 A 6 ... indicate aspheric coefficients.
また、かかる接眼レンズにおいては、下記条件を満足
することが好ましい。It is preferable that the eyepiece satisfy the following conditions.
（１）＜1.60 ここで、は各レンズの屈折率の平均値を示す。(1) <1.60 Here, indicates the average value of the refractive index of each lens.
更に、前記接眼レンズにおいて、下記条件を満足する
ことが好ましい。Further, it is preferable that the eyepiece lens satisfies the following conditions.
（２）−4.0＜f4/f＜−0.5 ここで、f4は第４レンズの焦点距離,fは全系の焦点距
離を示す。(2) −4.0 <f 4 /f<−0.5 where f 4 indicates the focal length of the fourth lens, and f indicates the focal length of the entire system.
「作用」 樹脂製の光学材料を接眼レンズに採用することは、樹
脂製の光学材料の加工性の良さや量産性からも有利であ
り、また像面湾曲及び非点収差の補正に効果のある非球
面形状のレンズの加工も容易であることから、高屈折率
の光学レンズ以上に安定した像面を得ることができる。[Function] The use of a resin optical material for the eyepiece is advantageous from the viewpoint of good workability and mass productivity of the resin optical material, and is effective in correcting field curvature and astigmatism. Since an aspherical lens can be easily processed, a more stable image surface can be obtained than an optical lens having a high refractive index.
加えて、少なくとも１面に非球面を設けたことによ
り、レンズ枚数を増やすことなく容易に収差補正が行え
るものである。In addition, since at least one aspherical surface is provided, aberration correction can be easily performed without increasing the number of lenses.
また、条件式（１）は各レンズの屈折率の平均値を示
し、低屈折率の光学材料を用いることによって低コスト
の接眼レンズを実現させている。The conditional expression (1) indicates the average value of the refractive index of each lens, and realizes a low-cost eyepiece by using an optical material having a low refractive index.
つぎに条件式（２）の上限を越えた場合には、第４レ
ンズのパワーが過大になり、周辺光束が通りにくくな
り、画角を広げることが困難になる。下限を越えた場合
は、ペッツバール和が大きくなってしまう。Next, when the value exceeds the upper limit of the conditional expression (2), the power of the fourth lens becomes excessive, the peripheral light beam becomes difficult to pass, and it becomes difficult to widen the angle of view. If the lower limit is exceeded, the Petzval sum will increase.
「実施例」 以下、この発明の実施例のデータを示す。ここで、ｆ
は全系の焦点距離、FNOはＦナンバー、２ωは視野角、
ｒはレンズ各面の曲率半径、ｄはレンズ厚またはレンズ
間隔、ｎは各レンズのｄ−lineの屈折率、νは各レンズ
のアッベ数を示す。"Example" Hereinafter, data of an example of the present invention will be shown. Where f
Is the focal length of the entire system, F NO is the F number, 2ω is the viewing angle,
r is the radius of curvature of each lens surface, d is the lens thickness or lens spacing, n is the d-line refractive index of each lens, and ν is the Abbe number of each lens.
「発明の効果」 以上説明したように、この発明によれば、４枚構成の
接眼レンズにおいて、加工性が良く重産性に有利な樹脂
製光学材料を２枚以上用いるため、低コストで軽量であ
りながら、しかも非球面を設けたことにより容易に広視
野まで十分収差補正された接眼レンズが得られる。 [Effects of the Invention] As described above, according to the present invention, in a four-piece eyepiece, two or more resin optical materials having good workability and advantageous for high productivity are used, so that the cost and weight are low. However, the provision of the aspherical surface makes it possible to easily obtain an eyepiece that is sufficiently corrected for aberrations up to a wide field of view.
第１図は、この発明の実施例１のレンズ断面図、 第２図は、その諸収差図である。 第３図は、この発明の実施例２のレンズ断面図、 第４図は、その諸収差図である。 第５図は、この発明の実施例３のレンズ断面図、 第６図は、その諸収差図である。 第７図は、この発明の実施例４のレンズ断面図、 第８図は、その諸収差図である。 第９図は、この発明の実施例５のレンズ断面図、 第10図は、その諸収差図である。 FIG. 1 is a sectional view of a lens according to a first embodiment of the present invention, and FIG. 2 is a diagram showing various aberrations. FIG. 3 is a sectional view of a lens according to a second embodiment of the present invention, and FIG. 4 is a diagram showing various aberrations. FIG. 5 is a sectional view of a lens according to Embodiment 3 of the present invention, and FIG. 6 is a diagram showing various aberrations. FIG. 7 is a sectional view of a lens according to a fourth embodiment of the present invention, and FIG. 8 is a diagram showing various aberrations. FIG. 9 is a sectional view of a lens according to a fifth embodiment of the present invention, and FIG. 10 is a diagram showing various aberrations.
───────────────────────────────────────────────────── フロントページの続き (58)調査した分野(Int.Cl.6，ＤＢ名) G02B 9/00 - 17/08 G02B 21/02 - 21/04 G02B 25/00 - 25/04 ──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int. Cl. 6 , DB name) G02B 9/00-17/08 G02B 21/02-21/04 G02B 25/00-25/04
Claims (2)
負メニスカスレンズの第２レンズと、正レンズの第３レ
ンズと、負レンズの第４レンズとから構成され、第１レ
ンズと第２レンズは光学ガラスまたは樹脂製の光学材料
からなり、第３レンズと第４レンズは樹脂製の光学材料
からなり、そのなかの少なくとも１面が で表わされる非球面であり、さらに下記条件を満足する
ことを特徴とする４枚のレンズで構成される接眼レン
ズ。 −4.0＜f4/f＜−0.5 ここで、Ｘはレンズ頂点から光軸方向への偏移量,yはレ
ンズ頂点から光軸に垂直な方向への偏移量,Cは曲率半径
の逆数,Kは円錐係数,A4A6……は非球面係数を示し、f4
は第４レンズの焦点距離,fは全系の焦点距離を示す。1. A first lens of a positive lens, in order from an eye side,
The second lens of the negative meniscus lens, the third lens of the positive lens, and the fourth lens of the negative lens, the first lens and the second lens are made of optical material made of optical glass or resin, and the third lens And the fourth lens are made of an optical material made of resin, and at least one surface thereof is An eyepiece comprising four lenses, which is an aspheric surface represented by the following formula and further satisfies the following condition. −4.0 <f 4 /f<−0.5 where X is the amount of deviation from the lens vertex to the optical axis direction, y is the amount of deviation from the lens vertex to the direction perpendicular to the optical axis, and C is the reciprocal of the radius of curvature. , K is the conic coefficient, A 4 A 6 …… is the aspheric coefficient, f 4
Denotes the focal length of the fourth lens, and f denotes the focal length of the entire system.
とを特徴とする接眼レンズ。 ＜1.60 ここで、は各レンズの屈折率の平均値を示す。2. An eyepiece according to claim 1, wherein the following condition is satisfied. <1.60 Here, indicates the average value of the refractive index of each lens.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US07/544,721 US5162945A (en) | 1989-06-27 | 1990-06-27 | Ocular lens system |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16509789 | 1989-06-27 | ||
| JP1-165097 | 1989-06-27 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0387710A JPH0387710A (en) | 1991-04-12 |
| JP2902444B2 true JP2902444B2 (en) | 1999-06-07 |
Family
ID=15805833
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2104997A Expired - Fee Related JP2902444B2 (en) | 1989-06-27 | 1990-04-20 | Eyepiece |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2902444B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6011655A (en) * | 1995-01-17 | 2000-01-04 | Asahi Kogaku Kogyo Kabushiki Kaisha | Eyepiece |
| JPH08254660A (en) * | 1995-01-17 | 1996-10-01 | Asahi Optical Co Ltd | Eyepiece lens |
-
1990
- 1990-04-20 JP JP2104997A patent/JP2902444B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0387710A (en) | 1991-04-12 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20090319 Year of fee payment: 10 |
|
| LAPS | Cancellation because of no payment of annual fees |