JPS61126513A - Photographic lens - Google Patents

Abstract

PURPOSE:To obtain a lightweight, inexpensive high-precision photographic lens which consists of a small number of elements and is easily assembled by composing a lens barrel of two split lens barrels which abutting on each other in a plane containing the optical axis of the lens. CONSTITUTION:Lenses 11, 12, and 13 are pressed in and inserted into grooves 22, 23, and 24 along shoulders 16, 17, and 18 as key drivers of one split lens barrel 10 while inner collars 19, 20, and 21 are deformed elastically. The lenses 11-13 are inserted at accurate lens intervals by contacting the shoulders 16-18 and also clamped with the reaction force resulting from the semicircular elastic deformation on the split lens barrel 10 which is almost in such a U shape that the radius R1 of an opening part is smaller than the depth-directional radius R2. Then, the other split lens barrel 10 is set in abutting relation and tenons 14 of the both are fitted in mortises. The inner peripheral length of grooves 22-24 is a half as large as the outer peripheral length of the lenses 11-13, so the lenses 11-13 are mounted in the grooves 22-24 without any gap. Then, abutting surfaces of the split lens barrels 10 are fixed by ultrasonic melt-sticking or with an adhesive, etc.

Description

【発明の詳細な説明】 （産業上の利用分野） 本発明はビデオカメラなどの光学機器に使用する写真レ
ンズに関するものである。DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a photographic lens used in optical equipment such as a video camera.

（従来例の構成とその問題点） ビデオカメラなどの光学機器の小形軽量化および価額低
廉化のために、写真レンズのレンズや鏡胴部品の樹脂化
が盛んに行なわれている。(Constitution of Conventional Examples and Problems thereof) In order to reduce the size, weight, and cost of optical equipment such as video cameras, lenses and barrel parts of photographic lenses are increasingly being made of resin.

従来の写真レンズについて第１図および第２図により説
明する。A conventional photographic lens will be explained with reference to FIGS. 1 and 2.

第１図は従来の写真レンズの断面図で、写真レンズは、
外周面に雄ねじｌａを形成した鏡胴１に、上記の雄ねじ
ｌａに噛み合う雌ねじ２ａを内周面に形成した蓋２が、
これら雄雌ねじ１ａおよび２ａの働きで締め付けられた
中に、４枚のレンズ３ないし６と、これらのレンズ３な
いし６のそれぞれの間に入れて正しい間隔に位置決めす
る３個の間座７ないし９が挿入された構造を有している
。Figure 1 is a cross-sectional view of a conventional photographic lens.
A lens barrel 1 has a male thread la formed on its outer peripheral surface, and a lid 2 has a female thread 2a formed on its inner peripheral surface that engages with the male thread la.
Tightened by the action of these male and female screws 1a and 2a, there are four lenses 3 to 6, and three spacers 7 to 9 inserted between each of these lenses 3 to 6 to position them at correct intervals. It has a structure in which is inserted.

このような写真レンズの組立て方法を第２図により説明
する。第２１１ｉ！ｉは、第１図の写真レンズの構成部
品を組立ての手順に従って下から順に配列した構成部品
の斜視図で１組立て手順は、雄ねじｌａ側を上にした鏡
胴１に、レンズ３を挿入し、レンズ３の上に間座７を載
せ、順次レンズ４と間座８、レンズ５と間座９の挿入を
繰り返して最後のレンズ６を挿入した後、蓋２をねじｌ
ａおよび２ａで締めて固定する手順となる。A method of assembling such a photographic lens will be explained with reference to FIG. 211i! i is a perspective view of the components of the photographic lens shown in Figure 1 arranged in order from the bottom according to the assembly procedure. 1 The assembly procedure is to insert the lens 3 into the lens barrel 1 with the male screw la side facing up. , place the spacer 7 on top of the lens 3, repeat the insertion of the lens 4 and the spacer 8, and the lens 5 and the spacer 9 in order, insert the last lens 6, and then screw the lid 2.
The procedure is to tighten and fix with steps a and 2a.

しかしながら、上述の構造を有する写真レンズでは、各
レンズ３ないし６をそれぞれ間座７ないし９を重ねるこ
とによって位置決めするため、各間座７ないし９の幅寸
法の許容差が累積されるため、写真レンズの焦点距離の
許容差を大きく設定せざるを得ないという問題点があっ
た。However, in the photographic lens having the above-mentioned structure, each lens 3 to 6 is positioned by overlapping the spacers 7 to 9, respectively, so that the tolerance of the width dimension of each spacer 7 to 9 is accumulated. There was a problem in that the tolerance of the focal length of the lens had to be set large.

また、レンズ５のように薄いレンズでは、鏡胴１にレン
ズ５を落とし込む際に、反転することがあり、作業性が
悪いという問題点もあった。また、表裏面の曲率半径が
ほぼ等しいレンズが組み込まれる場合、誤って表裏逆方
向に挿入し完成品検査工程で発見され再組立てに戻され
たときに、分解組立ての工数が大きいという問題点もあ
った。Furthermore, with a thin lens like the lens 5, the lens 5 may be turned upside down when it is dropped into the lens barrel 1, resulting in a problem of poor workability. In addition, when a lens with approximately the same radius of curvature on the front and back surfaces is incorporated, there is the problem that if the front and back surfaces are accidentally inserted in the opposite direction and it is discovered during the finished product inspection process and the lens is returned to reassembly, the number of steps required for disassembly and reassembly will be large. there were.

また、各レンズ間にそれぞれ間座が必要なため部品点数
が多くなり、その寸法精度を厳しく規定する必要がある
という問題点もあった。Furthermore, since a spacer is required between each lens, the number of parts increases, and there is also the problem that the dimensional accuracy of the parts must be strictly specified.

（発明の目的） 本発明は上記の欠点を解消するもので、構成部品点数が
少なく１組立てが簡単で、高精度の組立て精度が得られ
、しかも軽量で安価な写真レンズを提供しようとするも
のである。(Objective of the Invention) The present invention aims to eliminate the above-mentioned drawbacks, and provides a photographic lens that has a small number of component parts, is easy to assemble, has high assembly accuracy, and is lightweight and inexpensive. It is.

（発明の構成） 複数枚のレンズと、これらのレンズを位置決めして保持
する複数箇所の溝が形成され、レンズ光軸を含む平面で
突き合わされた２個の分割鏡胴とから写真レンズを構成
し、分割鏡胴のレンズ保持用の溝を、レンズの位置を正
確に決める胴突きとなる肩とレンズを確実に押さえた状
態で保持する弾性を持たせた内側鍔で構成し、レンズは
分割した開口部を利用してレンズ光軸に鉛直な方向から
それぞれ独立に挿入できるようにし、かつ、レンズ挿入
前の分割鏡胴の溝の断直形状を、開口部の半径を深さ方
向の半径より小さく、はぼＵ字形の形状を呈するように
するとともに、溝の内周長さをこれに挿入するレンズの
外周長さのほぼ半分として、挿入したレンズが把持され
て組立て作業中の脱落を防ぐとともに、各レンズの光軸
を正確に合致させようとするものである。(Structure of the Invention) A photographic lens is composed of a plurality of lenses and two divided lens barrels in which grooves are formed at a plurality of locations to position and hold these lenses, and are butted against each other on a plane including the lens optical axis. The groove for holding the lens in the split barrel is made up of a shoulder that serves as a shoulder to accurately determine the position of the lens, and an elastic inner flange that holds the lens firmly in place. By using the opening, each lens can be inserted independently from the direction perpendicular to the optical axis, and the vertical shape of the groove of the divided lens barrel before the lens is inserted is set so that the radius of the opening is smaller than the radius in the depth direction. The groove is small and has a U-shaped shape, and the inner circumference of the groove is approximately half the outer circumference of the lens to be inserted, so that the inserted lens is gripped and prevented from falling off during assembly. At the same time, the optical axis of each lens is made to match accurately.

（実施例の説明） 本発明の実施例を第３図ないし第５図により説明する。(Explanation of Examples) Embodiments of the present invention will be explained with reference to FIGS. 3 to 5.

第３図に本発明による写真レンズの斜視図を、第４図に
第３図の写真レンズの分割鏡胴の平面図をそれぞれ示す
。これら両側において１本発明の写真レンズは、黒色ガ
ラス入りポリカーボネートで形成された２個の同一形状
の分割鏡１１ｉｉ１０と、３個のレンズ１１ないし１３
で構成されている。FIG. 3 is a perspective view of a photographic lens according to the present invention, and FIG. 4 is a plan view of a divided lens barrel of the photographic lens shown in FIG. 3. On both sides, the photographic lens of the present invention includes two split mirrors 11ii10 of the same shape made of black glass-filled polycarbonate, and three lenses 11 to 13.
It consists of

分割鏡胴ｌＯは１両側の突合わせ面には、その中央にそ
れぞれ断面矩形のほぞ１４およびほぞ穴１５が形成され
、内周面には、３個のレンズ１１ないし１３の位置決め
をする胴突きとなる肩１６ないし１８と。A tenon 14 and a mortise 15 each having a rectangular cross section are formed in the center of the abutting surfaces on both sides of the divided lens barrel 10, and a barrel abutment for positioning the three lenses 11 to 13 is formed on the inner circumferential surface. Shoulders 16 to 18.

各レンズ１１ないし１３を肩１６ないし１８に密着する
ように押し付けて保持する弾性を有する内側鍔１９ない
し２１とでそれぞれ構成された溝２２ないし２４が形成
されており、さらに第５図に示すように上記の溝２２な
いし２４の開口部の半径Ｒ工が深さ方向の半径Ｒ２より
小さくほぼＵ字形の形状を有し、その内周長さが、レン
ズの外周長さのほぼ半分となるように形成されている。Grooves 22 to 24 are formed respectively with inner flanges 19 to 21 having elasticity to press and hold the lenses 11 to 13 in close contact with the shoulders 16 to 18, and as shown in FIG. The radius R of the opening of the grooves 22 to 24 is smaller than the radius R2 in the depth direction and is approximately U-shaped, and the inner circumference length thereof is approximately half of the outer circumference length of the lens. is formed.

なお、第５図は第４図に示すＸ−Ｘ平面で切断した断面
図である。また、Ｕ字形状の分割ａｕｔ。Note that FIG. 5 is a sectional view taken along the X-X plane shown in FIG. 4. Also, there is a U-shaped split out.

は、Ｕ字形状の特別な金型を必要とせず、半円形状の金
型を用い、成形条件を制御することにより容易に成形す
ることができた。did not require a special U-shaped mold, but could be easily molded by using a semicircular mold and controlling the molding conditions.

以上のような構成の写真レンズの組立て方法を説明する
と、１個の分割鏡胴１０の胴突きとなる肩１６ないし１
８に沿ってレンズ１１ないし１３を１個ずつそれぞれの
内側鍔１９ないし２１を弾性変形させながら溝２２ない
し２４に、レンズ１１ないし１３を押し込んで挿入する
。各レンズ１１ないし１３は、それぞれ胴突きとなる肩
１６ないし１８に密着することにより、正確なレンズ間
隔に挿入されるとともに、Ｕ字形の分割鏡胴１０が半円
形に弾性変形された反力で脱落しないように把持される
。To explain the method of assembling the photographic lens having the above-mentioned structure, the shoulder 16 or 1 which serves as the body abutment of one divided lens barrel 10 will be explained.
The lenses 11 to 13 are pushed into the grooves 22 to 24 one by one along the grooves 22 to 24 while elastically deforming the respective inner flanges 19 to 21. The lenses 11 to 13 are inserted at accurate lens intervals by coming into close contact with the shoulders 16 to 18, which serve as barrel thrusters, respectively, and fall off due to the reaction force caused by the U-shaped split lens barrel 10 being elastically deformed into a semicircular shape. be held so as not to

レンズ１１ないし１３が装着された分割鏡胴１０に、他
の分割鏡胴１０を突き合わせ、それぞれのほぞ１４をほ
ぞ穴１５に嵌合する。上記の溝２２ないし２４の内周長
さはレンズ１１ないし１３の外周長さの半分に形成され
ているので、２個の分割鏡胴１０を突き合ねせて密着す
ると、レンズ１１ないし１３はそれぞれの溝２２ないし
２４の中に隙間なく装着されることになる。The divided lens barrel 10 on which the lenses 11 to 13 are attached is matched with another divided lens barrel 10, and each tenon 14 is fitted into a mortise 15. Since the inner circumferential length of the grooves 22 to 24 is half the outer circumferential length of the lenses 11 to 13, when the two divided lens barrels 10 are brought into close contact with each other, the lenses 11 to 13 are It will be installed in each of the grooves 22 to 24 without any gaps.

このようにして組立てた後、分割鏡胴１０の突き合わせ
面を超音波溶着あるいは接着剤などで固着する。After assembling in this manner, the abutting surfaces of the divided lens barrels 10 are fixed by ultrasonic welding or adhesive.

このようにして、構成部品点数が少なく１組立てが簡単
な軽量で安価な高精度写真レンズが得られる。In this way, it is possible to obtain a lightweight, inexpensive, high-precision photographic lens that has a small number of component parts and is easy to assemble.

なお、上述の実施例では１分割鏡胴１０の材質として黒
色ガラス人リポリカーボネートを用いたが、温度による
寸法変化が少なく、精密成形材料として適する黒色の材
料であれば何でもよい０例えば、黒色ノリル等を用いる
ことができる。In the above embodiment, black glass polycarbonate was used as the material for the one-segment lens barrel 10, but any black material may be used as long as it has little dimensional change due to temperature and is suitable as a precision molding material.For example, black Noryl etc. can be used.

（発明の効果） 以上説明したように、本発明によれば、従来必要であっ
た間座をなくすることができ、構成部品点数が少なく、
複数のレンズの位置をそれぞれ単独にｆｉ胴との関係位
置で位置決めできるので、焦点距離の許容差が極めて小
さく規定でき、組立て作業が簡単で、しかも軽く安価な
高精度の写真レンズを得ることができる。(Effects of the Invention) As explained above, according to the present invention, it is possible to eliminate the spacer that was conventionally necessary, and the number of component parts is small.
Since the positions of multiple lenses can be determined independently in relation to the FI cylinder, the tolerance of the focal length can be specified to be extremely small, and the assembly work is simple, and it is possible to obtain a lightweight, inexpensive, and high-precision photographic lens. can.

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

第１図は従来の写真レンズの断面図、第２図は第１図の
写真レンズの構成部品を組立て順に配列した斜視図、第
３図は本発明による写真レンズの斜視図７第４図は第３
図の写真レンズの平面図、第５図は第４図Ｘ−Ｘａ　　
の断面図である。 １　・・・鏡胴、　　ｌａ・・・雄ねじ、　２・・・蓋
。 ２ａ　　・・雌ねじ、　３．４．５．６．１１，１２，
１３・・・　レンズ、　？、８．９　・・・間座、ＩＯ
・・・分割鏡胴、Ｉ４・・・はぞ、　　１５・・・はぞ
穴、１６゜１７．１８・・・胴突きとなる肩、　　１９
，２０，２１・・・内側鍔、　　２２，２３．２４・・
・溝、Ｒ１・・・溝の開口部の半径、Ｒ８・・・深さ方
向の半径。FIG. 1 is a cross-sectional view of a conventional photographic lens, FIG. 2 is a perspective view showing the components of the photographic lens shown in FIG. 1 arranged in the order of assembly, and FIG. 3 is a perspective view of the photographic lens according to the present invention. Third
The plan view of the photographic lens shown in the figure, Figure 5 is Figure 4 X-Xa.
FIG. 1... Lens barrel, la... Male screw, 2... Lid. 2a...Female thread, 3.4.5.6.11, 12,
13... Lens, ? , 8.9 ... Maza, IO
...Divided lens barrel, I4...Slot, 15...Slot, 16°17.18...Shoulder for barrel thrust, 19
,20,21...inner tsuba, 22,23.24...
-Groove, R1... Radius of the opening of the groove, R8... Radius in the depth direction.

Claims (1)

【特許請求の範囲】[Claims] 複数枚のレンズと、これらのレンズを位置決めして保持
する複数箇所の溝が形成され、レンズ光軸を含む平面で
突き合わされた２個の分割鏡胴とからなり、上記の分割
鏡胴の内部の複数箇所の溝がレンズの胴突きとなる肩と
レンズを保持する内側鍔で構成され、かつ、溝の分割開
口部の半径が深さ方向の半径より小さく、溝の断直形状
がほぼＵ字形を呈し、溝の内周長さがレンズの外周長さ
のほぼ半分になるように構成されたことを特徴とする写
真レンズ。It consists of a plurality of lenses and two divided lens barrels that are formed with grooves at multiple locations to position and hold these lenses, and that are butted against each other on a plane that includes the lens optical axis. The grooves at multiple locations are composed of a shoulder that serves as the body of the lens and an inner flange that holds the lens, and the radius of the dividing opening of the groove is smaller than the radius in the depth direction, and the straight cross section of the groove is approximately U-shaped. 1. A photographic lens characterized in that the length of the inner circumference of the groove is approximately half of the length of the outer circumference of the lens.