JPH0241006B2 - - Google Patents

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Publication number
JPH0241006B2
JPH0241006B2 JP60095170A JP9517085A JPH0241006B2 JP H0241006 B2 JPH0241006 B2 JP H0241006B2 JP 60095170 A JP60095170 A JP 60095170A JP 9517085 A JP9517085 A JP 9517085A JP H0241006 B2 JPH0241006 B2 JP H0241006B2
Authority
JP
Japan
Prior art keywords
lens
focal length
mirror
correction lens
correction
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 - Lifetime
Application number
JP60095170A
Other languages
Japanese (ja)
Other versions
JPS61252519A (en
Inventor
Shoichi Araya
Yoichiro Mitsuka
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.)
Goto Optical Manufacturing Co Ltd
Original Assignee
Goto Optical Manufacturing Co Ltd
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 Goto Optical Manufacturing Co Ltd filed Critical Goto Optical Manufacturing Co Ltd
Priority to JP9517085A priority Critical patent/JPS61252519A/en
Publication of JPS61252519A publication Critical patent/JPS61252519A/en
Publication of JPH0241006B2 publication Critical patent/JPH0241006B2/ja
Granted legal-status Critical Current

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Description

【発明の詳細な説明】[Detailed description of the invention]

イ) 産業上の利用分野 この発明は、反射式天体望遠鏡において、主鏡
に抛物面鏡を用いたニユートン式反射鏡に付加
し、光学性能の改良をはかる補正レンズの光学系
に係わるものである。 ロ) 従来の技術 天体望遠鏡は対物面鏡の構成によつて屈折式と
反射式の二通りに大別できる。 反射式望遠鏡の中で最も簡易的なものは、ニユ
ートン式反射望遠鏡と言われる対物面鏡の鏡面に
回転抛物面を用いるものである。 この鏡面は回転抛物面であるために鏡面に入射
する平行光線は無収差で一点収斂するが、コマ収
差が残存しているので狭い視界しか取れない欠点
がある。 抛物面鏡のコマ補正を目的とした補正レンズに
はロスの補正レンズと呼ばれるものがある。 第7図に示す如く、ロスの補正レンズは抛物面
鏡の焦点位置近傍に置かれた空気間隔を有する二
枚の正負のレンズLから構成されており、Lp抛
物面鏡、Lロスの補正レンズ、Po抛物面鏡の焦
点位置、Pロスの補正レンズを挿入した時の焦点
位置、を示す。 上記ロスの補正レンズの焦点距離はアフオーカ
ルか又はアフオーカルに近いものである。 ロスの補正レンズは本来は零である球面収差を
アンダーに残存させることによつてコマ収差を補
正しているので、抛物面鏡のFナンバーが6以下
の対物面鏡に多く利用されており、又、コマ収差
の補正も充分でないため有効視界も全角1゜位であ
る。 ハ) 発明が解決しようとする問題点 この発明は上記の如き従来技術の欠点を解決し
ようとするものである。 ニ) 問題を解決するための手段 この発明の抛物面鏡の補正レンズは、抛物面鏡
のFナンバーが4、0、有効視界が2゜の範囲で球
面収差、コマ収差及び非点収差を補正するために
次の手段を採用したものである。 すなわち、第1図に示す如く、Lp抛物面鏡、
fp抛物面鏡の焦点距離、Po抛物面鏡の焦点位置、
P抛物面鏡に補正レンズを挿入した光学系の焦点
位置、Ro抛物面鏡の接触円半径、R1〜R8補
正レンズの曲率半径、L補正レンズ、f′補正レン
ズの焦点距離、lp抛物面鏡の頂点と補正レンズ頂
点との距離、t1〜t4レンズの肉厚、d1〜d
2空気間隔、L1,2補正レンズの前群レンズ、
L1,L2補正レンズの前群レンズを構成する各
レンズ、L3,4補正レンズの後群レンズ、L
3,L4補正レンズの後群レンズを構成する各レ
ンズ、f1補正レンズの前群レンズの焦点距離、
f2補正レンズの後群レンズの焦点距離、l補正
レンズ前面から抛物面鏡焦点迄の距離、l′補正レ
ンズの前群レンズと後群レンズとの大きな空気間
隔として、アフオーカル又はアフオーカルに近い
焦点距離f′を有し、各々がアフオーカル又はアフ
オーカルに近い焦点距離f1,f2を有する多数
枚の負、正レンズからなる前群レンズL1,2と
後群レンズL3,4から構成されており、抛物面
鏡の焦点距離をfpとすると、 補正レンズの挿入位置lは 0.05fp<l<0.25fp ……(1) 前群レンズと後群レンズの空気間隔l′は 0.02fp<l′<0.1fp ……(2) 補正レンズの焦点距離f′、前群レンズの焦点距
離f1、後群レンズの焦点距離f2は 1.0fp<f′,f1,f2<∞ ……(3) 前群レンズL1,2において、各レンズL1,
L2の曲率半径をR1,R2,R3,R4、とす
ると R3<R4<R2<|R1| ……(4) 後群レンズL3,4において各レンズL3,L
4の曲率半径をR5,R6,R7,R8とすると R6<R7<R5<|R8| ……(5) の(1)〜(5)を満足して得られる光学系としたもので
ある。 ホ) 作用 上記補正レンズの挿入位置lが抛物面鏡の焦点
位置のPoに近い程各レンズの曲率半径が小さく
なり、コマ収差の補正ができなくなるために、l
は1式の範囲内に抑えなければならない。 又、2式において前群レンズと後群レンズの空
気間隔l′は1式のlと同じように曲率半径の大き
さに影響し、2式の範囲を越した値をとると、特
に非点収差の補正が困難となる。 3式は本補正レンズが球面収差及び非点収差を
小さく抑えるための条件であり、補正レンズの焦
点距離と前群後群レンズの焦点距離を規制するも
のである。 4、5式は球面収差を抑えるための必要条件で
あり、補正レンズの各面のうち、R2,R3,R
4は抛物面鏡に対し凸面を向けることにより球面
収差の発生を抑えている。 ヘ) 実施例 実施例 一 第1図に示す如く (抛物面鏡+補正レンズ)の焦点距離
f=1197.30mm (抛物面鏡+補正レンズ)の後側焦点距離
Bf=59.62mm (抛物面鏡+補正レンズ)のFナンバー F=4.0 抛物面鏡の焦点距離 fp=1200mm 抛物面鏡のFナンバー Fp=4.0 補正レンズの焦点距離 f′=4484.9mm 補正レンズの後側焦点距離 Bf′=4534.5mm 補正レンズ前群レンズの焦点距離 f1=3×105mm 補正レンズ前群レンズの後側焦点距離
Bf1=3×105mm 補正レンズ後群レンズの焦点距離 f2=4472.4mm 補正レンズ後群レンズの後側焦点距離
Bf2=4600.8mm 補正レンズ前面から抛物面鏡焦点迄の距離
l=156mm
B) Industrial Application Field The present invention relates to an optical system of a correction lens that is added to a Newtonian reflector using a parapetal mirror as the primary mirror in a reflecting astronomical telescope to improve optical performance. B) Conventional technology Astronomical telescopes can be roughly divided into two types, refractive type and reflective type, depending on the configuration of the objective mirror. The simplest type of reflecting telescope is the Newtonian reflecting telescope, which uses a rotating parapet surface as the mirror surface of the objective mirror. Since this mirror surface is a rotating parapet surface, parallel rays of light incident on the mirror surface converge to a single point without aberration, but comatic aberration remains, so it has the disadvantage that only a narrow field of view can be obtained. A correction lens for the purpose of coma correction of a parapetal mirror is called a loss correction lens. As shown in Fig. 7, the loss correction lens consists of two positive and negative lenses L with an air gap placed near the focal point of the parapet mirror, Lp, the L loss correction lens, and Po. The focal position of the parapet mirror and the focal position when the P loss correction lens is inserted are shown. The focal length of the loss correction lens is afocal or close to an afocal. Loss correction lenses correct comatic aberration by under-remaining spherical aberration, which is originally zero, so they are often used for objective mirrors with a parapetal mirror with an F number of 6 or less, and Since the correction of coma aberration is not sufficient, the effective field of view is only about 1° full angle. C) Problems to be Solved by the Invention This invention attempts to solve the above-mentioned drawbacks of the prior art. D) Means for Solving the Problem The correction lens for a parapetal mirror of the present invention is for correcting spherical aberration, coma aberration, and astigmatism within the range of an F number of 4 to 0 and an effective field of view of 2°. The following measures were adopted. That is, as shown in Fig. 1, Lp parabolic mirror,
Focal length of fp parapet mirror, focal position of Po parapet mirror,
The focal position of the optical system in which a correction lens is inserted into the P-parallel mirror, the radius of the contact circle of the Ro-paraparallel mirror, the radius of curvature of the R1 to R8 correction lenses, the focal length of the L-correction lens, the f' correction lens, and the vertex of the lp-paraparallel mirror. Distance from correction lens vertex, t1 to t4 Lens thickness, d1 to d
2 air spacing, L1, 2 correction lens front group lens,
Each lens forming the front group lens of the L1 and L2 correction lenses, the rear group lens of the L3 and 4 correction lenses, and the L
3. The focal length of each lens forming the rear group lens of the L4 correction lens, the front group lens of the f1 correction lens,
The focal length of the rear group lens of f2 correction lens, the distance from the front surface of l correction lens to the focal point of the parapetal mirror, and the large air distance between the front group lens and rear group lens of l' correction lens, focal length f that is afocal or close to afocal. It is composed of a front group lens L1, 2 and a rear group lens L3, 4, each consisting of a large number of negative and positive lenses each having an afocal or close to an afocal focal length f1, f2. If the focal length is fp, the correction lens insertion position l is 0.05fp<l<0.25fp...(1) The air distance l' between the front group lens and the rear group lens is 0.02fp<l'<0.1fp...( 2) The focal length f' of the correction lens, the focal length f1 of the front group lens, and the focal length f2 of the rear group lens are 1.0fp<f', f1, f2<∞...(3) In the front group lenses L1 and 2, Each lens L1,
Letting the radius of curvature of L2 be R1, R2, R3, R4, R3<R4<R2<|R1|...(4) In the rear group lenses L3, 4, each lens L3, L
Let R5, R6, R7, and R8 be the radii of curvature of R6<R7<R5<|R8|...(5).The optical system is obtained by satisfying (1) to (5). E) Effect The closer the insertion position l of the above correction lens is to the focal position Po of the parapetal mirror, the smaller the radius of curvature of each lens becomes, making it impossible to correct coma aberration.
must be kept within the range of 1 expression. In addition, in Equation 2, the air distance l' between the front group lens and the rear group lens affects the size of the radius of curvature in the same way as l in Equation 1, and if it takes a value that exceeds the range of Equation 2, it will especially cause astigmatism. It becomes difficult to correct aberrations. Equation 3 is a condition for this correction lens to suppress spherical aberration and astigmatism to a small value, and regulates the focal length of the correction lens and the focal lengths of the front and rear group lenses. Equations 4 and 5 are necessary conditions for suppressing spherical aberration, and among each surface of the correction lens, R2, R3, R
4 suppresses the occurrence of spherical aberration by orienting the convex surface to the parapetal mirror. F) Examples (1) Focal length of (parallel mirror + correction lens) as shown in Figure 1
f=1197.30mm (parallel mirror + correction lens) rear focal length
Bf=59.62mm (parallel mirror + correction lens) F number F=4.0 Focal length of the parapet mirror fp=1200mm F number of the parapet mirror Fp=4.0 Focal length of the correction lens f′=4484.9mm Rear focal length of the correction lens Bf′=4534.5mm Focal length of the front lens group of the correction lens f1=3×10 5 mm Rear focal length of the front lens group of the correction lens
Bf1=3×10 5 mm Focal length of correction lens rear group lens f2=4472.4mm Rear focal length of correction lens rear group lens
Bf2=4600.8mm Distance from the front of the correction lens to the focal point of the parapet mirror
l=156mm

【表】 尚、この実施例に対する本発明の制約条件の値
を示すと次の通りである。 (1)式0.05fp<l<0.25fpにおいて、 l=0.133fp (2)式0.02fp<l<0.1fpにおいて l′=0.063fp (3)式1.0fp<f′,f1,f2<∞において、 f′=4484.9=3.74fp f1=3×105=250fp f2=4472.4=3.73fp (4)式R3<R4<R2<|R1|において、 R3=74.36 R4=114.3 R2=160.1 R1=716.6 (5)式R6<R7<R5<|R8|において、 R6=43.0 R7=55.16 R5=143.1 R8=459.1 実施例 二 第2図に示す如く (抛物面鏡+補正レンズ)の焦点距離
f=1194.43mm (抛物面鏡+補正レンズ)の後側焦点距離
Bf=59.39mm (抛物面鏡+補正レンズ)のFナンバー F=4.0 抛物面鏡の焦点距離 fp=1200mm 抛物面鏡のFナンバー Fp4.0 補正レンズの焦点距離 f′=4481.6mm 補正レンズの後側焦点距離 Bf′=4520.0mm 補正レンズ前群レンズの焦点距離 f1=3×105mm 補正レンズ前群レンズの後側焦点距離
Bf1=3×105mm 補正レンズ後群レンズの焦点距離 f2=4472.4mm 補正レンズ後群レンズの後側焦点距離
Bf2=4600.8mm 補正レンズ前面から抛物面鏡焦点迄の距離
l=156mm
[Table] The values of the constraints of the present invention for this example are shown below. (1) In the equation 0.05fp<l<0.25fp, l=0.133fp (2) In the equation 0.02fp<l<0.1fp, l'=0.063fp (3) In the equation 1.0fp<f', f1, f2<∞ , f′=4484.9=3.74fp f1=3×10 5 =250fp f2=4472.4=3.73fp (4) In equation R3<R4<R2<|R1|, R3=74.36 R4=114.3 R2=160.1 R1=716.6 ( 5) In the formula R6<R7<R5<|R8|, R6=43.0 R7=55.16 R5=143.1 R8=459.1 Example 2 Focal length of (parallel mirror + correction lens) as shown in Figure 2
f = 1194.43mm (parallel mirror + correction lens) rear focal length
Bf=59.39mm (parallel mirror + correction lens) F number F=4.0 Focal length of the parapet mirror fp=1200mm F number of the parapet mirror Fp4.0 Focal length of the correction lens f′=4481.6mm Back focal length of the correction lens Bf′=4520.0mm Focal length of the front lens group of the correction lens f1=3×10 5 mm Rear focal length of the front lens group of the correction lens
Bf1=3×10 5 mm Focal length of correction lens rear group lens f2=4472.4mm Rear focal length of correction lens rear group lens
Bf2=4600.8mm Distance from the front of the correction lens to the focal point of the parapet mirror
l=156mm

【表】【table】

【表】 尚、この実施例に対する本発明の制約条件の値
を示すと次の通りである。 (1)式0.05fp<l<0.25fpにおいて、 l=0.134fp (2)式0.02fp<l<0.1fpにおいて l′=0.063fp (3)式1.0fp<f′,f1,f2<∞において、 f′=4481.6=3.73fp f1=3×105=250fp f2=4472.4=3.71fp (4)式R3<R4<R2<|R1|において、 R3=74.4 R4=114.3 R2=176 R1=1201 (5)式R6<R7<R5<|R8|において、 R6=43.0 R7=57.9 R5=126.2 R8=459.1 実施例 三 第3図に示す如く (抛物面鏡+補正レンズ)の焦点距離
f=1200.90mm (抛物面鏡+補正レンズ)の後側焦点距離
Bf=60.67mm (抛物面鏡+補正レンズ)のFナンバー F=4.0 抛物面鏡の焦点距離 fp=1200mm 抛物面鏡のFナンバー Fp=4.0 補正レンズの焦点距離 f′=4469.7mm 補正レンズの後側焦点距離 Bf′=4533.8mm 補正レンズ前群レンズの焦点距離 f1=3×105mm 補正レンズ前群レンズの後側焦点距離
Bf1=3×105mm 補正レンズ後群レンズの焦点距離 f2=4473.7mm 補正レンズ後群レンズの後側焦点距離
Bf2=4600.6mm 補正レンズ前面から抛物面鏡焦点迄の距離
l=156mm
[Table] The values of the constraints of the present invention for this example are shown below. (1) In the equation 0.05fp<l<0.25fp, l=0.134fp (2) In the equation 0.02fp<l<0.1fp, l'=0.063fp (3) In the equation 1.0fp<f', f1, f2<∞ , f′=4481.6=3.73fp f1=3×10 5 =250fp f2=4472.4=3.71fp (4) In equation R3<R4<R2<|R1|, R3=74.4 R4=114.3 R2=176 R1=1201 ( 5) In the formula R6<R7<R5<|R8|, R6=43.0 R7=57.9 R5=126.2 R8=459.1 Example 3 Focal length of (parallel mirror + correction lens) as shown in Figure 3
f = 1200.90mm (parallel mirror + correction lens) rear focal length
Bf = 60.67mm (parallel mirror + correction lens) F number F = 4.0 Focal length of parapet mirror fp = 1200mm F number of parapet mirror Fp = 4.0 Focal length of correction lens f′ = 4469.7mm Rear focal length of correction lens Bf′=4533.8mm Focal length of the front lens group of the correction lens f1=3×10 5 mm Rear focal length of the front lens group of the correction lens
Bf1=3×10 5 mm Focal length of the correction lens rear group lens f2=4473.7mm Rear focal length of the correction lens rear group lens
Bf2=4600.6mm Distance from the front of the correction lens to the focal point of the parapet mirror
l=156mm

【表】 尚、この実施例に対する本発明の制約条件の値
を示すと次の通りである。 (1)式0.05fp<l<0.25fpにおいて、 l=0.135fp (2)式0.02fp<l<0.1fpにおいて l′=0.063fp (3)式1.0fp<f′,f1,f2<∞において、 f′=4469.7=3.72fp f1=3×105=250fp f2=4473.7=3.72fp (4)式R3<R4<R2<|R1|において、 R3=74.4 R4=128.4 R2=176 |R1|=11500 (5)式R6<R7<R5<|R8|において、 R6=42.2 R7=60.6 R5=134.0 R8=1921.8 ト) 発明の効果 次にこの発明の性能を、第一実施例において第
4図A,B,C,D、第二実施例において第5図
A,B,C,D、第三実施例において第6図A,
B,C,Dの夫々の収差グラフの如く良好な収差
補正を示している。
[Table] The values of the constraints of the present invention for this example are shown below. (1) In the equation 0.05fp<l<0.25fp, l=0.135fp (2) In the equation 0.02fp<l<0.1fp, l'=0.063fp (3) In the equation 1.0fp<f', f1, f2<∞ , f′=4469.7=3.72fp f1=3×10 5 =250fp f2=4473.7=3.72fp (4) In formula R3<R4<R2<|R1|, R3=74.4 R4=128.4 R2=176 |R1|= 11500 (5) In formula R6<R7<R5<|R8|, R6=42.2 R7=60.6 R5=134.0 R8=1921.8 g) Effect of the invention Next, the performance of this invention is shown in Figure 4A in the first embodiment. , B, C, D, Fig. 5 A, B, C, D in the second embodiment, Fig. 6 A in the third embodiment,
The aberration graphs B, C, and D show good aberration correction.

【図面の簡単な説明】[Brief explanation of the drawing]

添付図面は本発明の実施例を示し、第1図は第
一実施例の光学系を示す側面図、第2図は第二実
施例の光学系を示す側面図、第3図は第三実施例
の光学系を示す側面図、第4図A,B,C,Dは
第一実施例の収差グラフ図を示し、Aは球面収
差、Bは非点収差、Cは歪曲収差、Dはコマ収差
を示し、第5図A,B,C,Dは第二実施例の収
差グラフ図を示し、Aは球面収差、Bは非点収
差、Cは歪曲収差、Dはコマ収差を示し、第6図
A,B,C,Dは第三実施例の収差グラフ図を示
し、Aは球面収差、Bは非点収差、Cは歪曲収
差、Dはコマ収差を示し、第7図は従来技術の光
学系を示す側面図である。 尚、図中符号L1,L2は前群レンズL1,2
の各レンズ、L3,L4は後群レンズL4,5の
各レンズである。
The attached drawings show embodiments of the present invention; FIG. 1 is a side view showing the optical system of the first embodiment, FIG. 2 is a side view showing the optical system of the second embodiment, and FIG. 3 is a side view showing the optical system of the second embodiment. 4A, B, C, and D show aberration graphs of the first embodiment, A is spherical aberration, B is astigmatism, C is distortion, and D is coma. 5A, B, C, and D show aberration graphs of the second embodiment, where A is spherical aberration, B is astigmatism, C is distortion, and D is comatic aberration. Figures 6A, B, C, and D show aberration graphs of the third embodiment, where A shows spherical aberration, B shows astigmatism, C shows distortion, and D shows comatic aberration, and Fig. 7 shows the conventional technology. FIG. 3 is a side view showing the optical system of FIG. In addition, the symbols L1 and L2 in the figure represent the front lens group L1 and 2.
The lenses L3 and L4 are the lenses of the rear lens group L4 and L5.

Claims (1)

【特許請求の範囲】 1 反射式天体望遠鏡において、主鏡に抛物面鏡
を用いたニユートン式反射鏡に付加する補正レン
ズに係わるもので、アフオーカル又はアフオーカ
ルに近い焦点距離f′を有する補正レンズLは、
各々がアフオーカル又はアフオーカルに近い焦点
距離f1,f2を有する負、正レンズからなる前
群レンズL1,2と後群レンズL3,4を大きな
空気間隔l′をとつて配置し、抛物面鏡の焦点距離
をfpとすると、補正レンズLの挿入位置lは、補
正レンズLの前面から抛物面鏡焦点位置Poまで
の距離で、 0.05fp<l<0.1fp ……(1) 前群レンズと後群レンズの空気間隔l′は、 0.02fp<l<0.1fp ……(2) 補正レンズの焦点距離f′:、前群レンズの焦点
距離f1、後群レンズの焦点距離f2は、 1.0fp<f′,f1,f2<∞ ……(3) 前群レンズL1,2において、各レンズL1,
L2の曲率半径をR1,R2,R3,R4とする
と、 R3<R4<R2<|R1| ……(4) 後群レンズL3,4において各レンズL3,L
4の曲率半径をR5,R6,R7,R8とする
と、 R6<R7<R5<|R8| ……(5) の(1)〜(5)を満足して得られることを特徴とする抛
物面鏡の補正レンズ。
[Claims] 1. In a reflecting astronomical telescope, the correction lens L is attached to a Newtonian reflector using a parapetal mirror as the primary mirror, and the correction lens L has an afocal or a focal length f' close to an afocal. ,
A front group lens L1, 2 and a rear group lens L3, 4, each consisting of a negative and a positive lens having an afocal or close to an afocal focal length f1, f2, are arranged with a large air distance l', and the focal length of a parabolic mirror is Let fp be the insertion position l of the correction lens L, which is the distance from the front surface of the correction lens L to the parapetal mirror focal point Po, and 0.05fp<l<0.1fp... (1) The distance between the front group lens and the rear group lens The air distance l' is 0.02fp<l<0.1fp... (2) Focal length f' of the correction lens: Focal length f1 of the front group lens, Focal length f2 of the rear group lens is 1.0fp<f', f1, f2<∞ ...(3) In the front lens group L1, 2, each lens L1,
If the radius of curvature of L2 is R1, R2, R3, R4, R3<R4<R2<|R1|...(4) In the rear group lenses L3, 4, each lens L3, L
R6<R7<R5<|R8|...(5) where the radius of curvature of 4 is R5, R6, R7, R8, R6<R7<R5<|R8| correction lens.
JP9517085A 1985-05-02 1985-05-02 Correction lens of parabolic mirror Granted JPS61252519A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP9517085A JPS61252519A (en) 1985-05-02 1985-05-02 Correction lens of parabolic mirror

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP9517085A JPS61252519A (en) 1985-05-02 1985-05-02 Correction lens of parabolic mirror

Publications (2)

Publication Number Publication Date
JPS61252519A JPS61252519A (en) 1986-11-10
JPH0241006B2 true JPH0241006B2 (en) 1990-09-14

Family

ID=14130285

Family Applications (1)

Application Number Title Priority Date Filing Date
JP9517085A Granted JPS61252519A (en) 1985-05-02 1985-05-02 Correction lens of parabolic mirror

Country Status (1)

Country Link
JP (1) JPS61252519A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0678708U (en) * 1993-04-17 1994-11-04 剛 重田 Shatterproof wall for cooker
JPH0718116U (en) * 1993-06-18 1995-03-31 岩谷産業株式会社 Rear shelf of table type gas stove

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5383052A (en) * 1992-05-27 1995-01-17 Dainippon Screen Mfg. Co., Ltd. Afocal optical system and multibeam recording apparatus comprising the same
JP5264395B2 (en) * 2008-10-03 2013-08-14 キヤノン株式会社 Astronomical telescope
JP2011175082A (en) * 2010-02-24 2011-09-08 Crystal System:Kk Telescope
CN102253479B (en) * 2011-07-29 2013-03-20 中国科学院光电技术研究所 Main focus type refraction and reflection optical system

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5810724B2 (en) * 1974-02-26 1983-02-26 キヤノン株式会社 Daikōkeihihanshiyataibutsukei
JPS6041328B2 (en) * 1975-04-24 1985-09-17 キヤノン株式会社 Large aperture specific reflection objective system
US4278330A (en) * 1979-05-14 1981-07-14 Applied Systems Corporation Catadioptric virtual-zoom optical system

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0678708U (en) * 1993-04-17 1994-11-04 剛 重田 Shatterproof wall for cooker
JPH0718116U (en) * 1993-06-18 1995-03-31 岩谷産業株式会社 Rear shelf of table type gas stove

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