JPH06144843A - Production of optical element - Google Patents

Production of optical element

Info

Publication number
JPH06144843A
JPH06144843A JP32244692A JP32244692A JPH06144843A JP H06144843 A JPH06144843 A JP H06144843A JP 32244692 A JP32244692 A JP 32244692A JP 32244692 A JP32244692 A JP 32244692A JP H06144843 A JPH06144843 A JP H06144843A
Authority
JP
Japan
Prior art keywords
lens
optical element
lens material
lower frame
frame
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.)
Withdrawn
Application number
JP32244692A
Other languages
Japanese (ja)
Inventor
Mitsuaki Takahashi
光明 高橋
Ryoichi Kitahara
良一 北原
Shinji Yokoyama
真司 横山
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.)
Olympus Corp
Original Assignee
Olympus Optical 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 Olympus Optical Co Ltd filed Critical Olympus Optical Co Ltd
Priority to JP32244692A priority Critical patent/JPH06144843A/en
Publication of JPH06144843A publication Critical patent/JPH06144843A/en
Withdrawn legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B11/00—Pressing molten glass or performed glass reheated to equivalent low viscosity without blowing
    • C03B11/06—Construction of plunger or mould
    • C03B11/08—Construction of plunger or mould for making solid articles, e.g. lenses
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B11/00—Pressing molten glass or performed glass reheated to equivalent low viscosity without blowing
    • C03B11/12—Cooling, heating, or insulating the plunger, the mould, or the glass-pressing machine; cooling or heating of the glass in the mould
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B2215/00—Press-moulding glass
    • C03B2215/79—Uniting product and product holder during pressing, e.g. lens and lens holder
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B2215/00—Press-moulding glass
    • C03B2215/80—Simultaneous pressing of multiple products; Multiple parallel moulds

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Organic Chemistry (AREA)

Abstract

PURPOSE:To provide a method for producing a lens having small diameter at a low cost while preventing the loss of the material. CONSTITUTION:A lens material 1 is placed between an upper frame 2 and a lower frame 3 and the hole 2a of the upper frame 2 is made to coincide with the hole 3a of the lower frame 3. The lens material 1 is softened by heating at 620 deg.C with a heater 4. The softened lens material 1 is pressed with the upper frame 2 and the lower frame 3 until both frames are brought into contact with each other. The softened lens material 1 is extruded through the holes 2a, 3a of the upper and the lower frames 2, 3. After forming a lens having a prescribed curvature radius R, the heater 4 is turned off and the lens material 1 is solidified to obtain lenses 1a.

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、顕微鏡或いは内視鏡の
対物レンズ等に用いられる微小径のレンズの製造方法及
び装置に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for manufacturing a lens having a small diameter used as an objective lens of a microscope or an endoscope.

【０００２】[0002]

【従来の技術】従来、上記微小径レンズの製造方法とし
ては、例えば特開平２−１３３３２６号公報に開示され
ている方法が知られている。この種光学素子の製造方法
を図５に基づいて説明する。2. Description of the Related Art Heretofore, as a method for manufacturing the above-mentioned minute lens, a method disclosed in, for example, Japanese Patent Application Laid-Open No. 2-133326 is known. A method of manufacturing this type of optical element will be described with reference to FIG.

【０００３】保持型１の上面には円柱状の凹部が形成さ
れており、この凹部２の底面２ａは平面状に形成されて
いる。凹部２の底面２ａに、レンズの平面側を成形する
成形型としての機能を有するので、鏡面加工が施されて
いる。保持型１の凹部２の上方には、円柱状の中空穴３
を有する円筒状の成形筒４が保持型１に対して接近離反
自在に設けられている。すなわち、成形筒４に、図示を
省略した加圧装置に連結されており、保持型１の凹部２
内に収容された光学素子素材５を押圧できるように設け
られている。A cylindrical recess is formed on the upper surface of the holding mold 1, and a bottom surface 2a of the recess 2 is formed in a flat shape. The bottom surface 2a of the recess 2 has a function as a molding die for molding the flat surface side of the lens, and thus is mirror-finished. Above the concave portion 2 of the holding mold 1, a cylindrical hollow hole 3 is formed.
A cylindrical molding tube 4 having a is provided so as to be able to move toward and away from the holding mold 1. That is, the molding cylinder 4 is connected to a pressurizing device (not shown), and the concave portion 2 of the holding mold 1 is connected.
It is provided so that the optical element material 5 housed inside can be pressed.

【０００４】また、成形筒４の中空穴３は、図示を省略
した圧力調整装置に連結されており、中空穴３内の圧力
を成形筒４外の圧力よりも減圧または増圧調整できるよ
うに設けられている。さらに、保持型１及び成形筒４の
周囲には、ヒータ６が配置されている。The hollow hole 3 of the molding cylinder 4 is connected to a pressure adjusting device (not shown) so that the pressure inside the hollow hole 3 can be adjusted to be lower or higher than the pressure outside the molding cylinder 4. It is provided. Further, a heater 6 is arranged around the holding die 1 and the molding cylinder 4.

【０００５】次に、このような構成の製造装置により平
凸レンズを形成した場合について説明する。光学素子素
材５としては、重フリントガラスＳＦ７を用いた。ま
ず、光学素子素材５を直径１２mm、厚さ３mmの平板に成
形した。そして、この光学素子素材５を保持型１の凹部
２内に嵌め込み、ヒータ６によって６１０℃になるまで
加熱した。Next, a case where a plano-convex lens is formed by the manufacturing apparatus having such a structure will be described. As the optical element material 5, heavy flint glass SF7 was used. First, the optical element material 5 was molded into a flat plate having a diameter of 12 mm and a thickness of 3 mm. Then, the optical element material 5 was fitted into the concave portion 2 of the holding mold 1 and heated by the heater 6 to 610 ° C.

【０００６】成形筒４の直径は８mm、中空穴３の内径は
３mmにそれぞれ設定した。光学素子素材５を加熱軟化し
た後、成形筒４の端部を１０ｋｇ／ｃm2の圧力で光学素
子素材５に押し込むとともに、中空穴３内の圧力を１×
１０-2 Ｔｏｒｒに減圧し、軟化状態にある光学素子素
材５の一部を中空穴３内に吸引した。この後、成形筒４
外の圧力は大気圧であった。これにより、光学素子素材
５は、前記減圧による吸引力と光学素子素材５の表面張
力とがつり合った状態で変形を停止し、球面状のレンズ
となった。The diameter of the molding cylinder 4 was set to 8 mm, and the inner diameter of the hollow hole 3 was set to 3 mm. After softening the optical element material 5 by heating, the end of the molding cylinder 4 is pushed into the optical element material 5 with a pressure of 10 kg / cm 2 , and the pressure in the hollow hole 3 is set to 1 ×.
The pressure was reduced to 10 -2 Torr, and part of the softened optical element material 5 was sucked into the hollow hole 3. After this, the forming cylinder 4
The outside pressure was atmospheric pressure. As a result, the optical element material 5 stopped being deformed in a state where the suction force due to the reduced pressure and the surface tension of the optical element material 5 were in balance, and became a spherical lens.

【０００７】このようにして成形したレンズを冷却して
保持型１から取り出すと、図５の（ｂ）図に示すような
平凸レンズ７を得ることができた。この平凸レンズ７の
凸面の形状は、有効径2.９mmまでが曲率半径が1.８２mm
であった。なお、曲率半径を変更するには、光学素子素
材５の加熱温度を軟化点よりも高い温度に変更するか、
中空穴３の圧力を調整すれば、容易に制御することがで
きる。When the lens thus molded was cooled and taken out from the holding mold 1, a plano-convex lens 7 as shown in FIG. 5 (b) could be obtained. The convex surface of the plano-convex lens 7 has a radius of curvature of 1.82 mm up to an effective diameter of 2.9 mm.
Met. To change the radius of curvature, change the heating temperature of the optical element material 5 to a temperature higher than the softening point, or
If the pressure of the hollow hole 3 is adjusted, it can be easily controlled.

【０００８】[0008]

【発明が解決しようとする課題】しかしながら、上記従
来の光学素子の製造方法にあっては、素材を瀬土する保
持型が必要である。従い製造装置が高価となり、レンズ
単価が高くなる。またこの製造方法では、実際にレンズ
として使うよりも素材の量が多く必要であり、素材が無
駄になるという問題があった。However, the above-mentioned conventional method for manufacturing an optical element requires a holding die for setting the material. Therefore, the manufacturing apparatus becomes expensive and the lens unit price becomes high. In addition, this manufacturing method has a problem that the amount of the material is larger than that actually used as a lens, and the material is wasted.

【０００９】本発明は、上記問題点に鑑みてなされたも
のであり、微小径のレンズを安価に、しかも素材を無駄
にすることなく製造できる方法を提供するものである。The present invention has been made in view of the above problems, and provides a method for manufacturing a lens having a small diameter at low cost and without wasting a material.

【００１０】[0010]

【課題を解決するための手段および作用】本発明の概略
図を示す図１に基づいて説明すると、１は板状のレンズ
材料である。２及び３は、それぞれ上枠、下枠であり、
板状体に円形の穴をあけたものである。４はレンズ材料
を加熱軟化させるヒータである。Means and Actions for Solving the Problems Referring to FIG. 1 which is a schematic view of the present invention, 1 is a plate-shaped lens material. 2 and 3 are an upper frame and a lower frame, respectively.
It is a plate with circular holes. Reference numeral 4 is a heater for heating and softening the lens material.

【００１１】次にレンズを製造する手順（工程）を説明
すると、上枠２と下枠３の間にレンズ材料１を挟持させ
る。ヒータ４で上枠２と下枠３に挟持されたレンズ材料
１を加熱し、軟化させる。所定粘度まで軟化させたら上
枠２と下枠３とでレンズ材料１を押圧し、上枠２と下枠
３とを当接させる。するとレンズ材料１が上枠２と下枠
３に設けた穴から押し出され、その粘度によって決まる
表面張力により球面を形成する。しかる後ヒータ４をＯ
ＦＦし、レンズ材料１を硬化させ、上枠２と下枠３内か
らレンズ１ａを取り出す。取り出したレンズ１ａの外周
は、従来の加工技術によって加工する。Next, the procedure (process) for manufacturing the lens will be described. The lens material 1 is sandwiched between the upper frame 2 and the lower frame 3. The lens material 1 sandwiched between the upper frame 2 and the lower frame 3 is heated by the heater 4 to be softened. After softening to a predetermined viscosity, the upper frame 2 and the lower frame 3 press the lens material 1 to bring the upper frame 2 and the lower frame 3 into contact with each other. Then, the lens material 1 is extruded from the holes provided in the upper frame 2 and the lower frame 3, and a spherical surface is formed by the surface tension determined by its viscosity. After that, turn on the heater 4
FF is performed to cure the lens material 1, and the lens 1a is taken out from the inside of the upper frame 2 and the lower frame 3. The outer periphery of the taken out lens 1a is processed by a conventional processing technique.

【００１２】[0012]

【実施例１】図２は、本実施例の光学素子の製造方法の
概略図を示すものであり、図１において、１は板状のレ
ンズ材料であり、ＰＢＭ２７を使用した。２は上枠、３
は下枠であり、ニッケル鋼板に円形の穴２ａ，３ａが設
けてある。これらの穴２ａ、３ａの穴径は2.５mmに設定
してある。４はレンズ材料１を加熱軟化させるヒータで
あり、レンズ材料１の周囲に設けられている。本実施例
では、直径が２mm、曲率半径Ｒが３mmの両凸レンズを製
造した。EXAMPLE 1 FIG. 2 shows a schematic view of a method for manufacturing an optical element of this example. In FIG. 1, 1 is a plate-shaped lens material, and PBM27 was used. 2 is the upper frame, 3
Is a lower frame, and circular holes 2a and 3a are provided in a nickel steel plate. The hole diameters of these holes 2a and 3a are set to 2.5 mm. A heater 4 softens and heats the lens material 1, and is provided around the lens material 1. In this example, a biconvex lens having a diameter of 2 mm and a radius of curvature R of 3 mm was manufactured.

【００１３】上記構成によりレンズ１ａを製造する場合
を説明すると、まず、上枠２と下枠３の間にレンズ材料
１を挟持させる。この場合上枠２の穴２ａと下枠３の穴
３ａの位置を合わせる。次にヒータ４により、レンズ材
料１を６２０℃に加熱し軟化させる。上枠２と下枠３で
レンズ材料１を押圧して、上枠２と下枠３を当接させ
る。すると軟化したレンズ材料１は、上枠２と下枠３の
穴２ａ，３ａから押し出される。そして軟化したレンズ
材料１の粘度により決まる表面張力とレンズ材料１の押
し出される量及び穴２ａ，３ａの径により、レンズ１ａ
の曲率半径Ｒが決まる。しかる後、ヒータ４をＯＦＦ
し、レンズ材料１を硬化させる。上枠２と下枠３との間
からレンズ１ａを取り出し、外周は従来の加工技術によ
り加工する。The case of manufacturing the lens 1a with the above structure will be described. First, the lens material 1 is sandwiched between the upper frame 2 and the lower frame 3. In this case, the holes 2a of the upper frame 2 and the holes 3a of the lower frame 3 are aligned. Next, the lens material 1 is heated to 620 ° C. and softened by the heater 4. The lens material 1 is pressed by the upper frame 2 and the lower frame 3 to bring the upper frame 2 and the lower frame 3 into contact with each other. Then, the softened lens material 1 is extruded from the holes 2 a and 3 a of the upper frame 2 and the lower frame 3. Then, depending on the surface tension determined by the viscosity of the softened lens material 1, the amount of the lens material 1 extruded, and the diameters of the holes 2a and 3a, the lens 1a
The radius of curvature R of is determined. After that, turn off the heater 4.
Then, the lens material 1 is cured. The lens 1a is taken out from between the upper frame 2 and the lower frame 3, and the outer periphery is processed by a conventional processing technique.

【００１４】本実施例によれば、微小径のレンズを安価
に、しかも素材を無駄にすることなく製造することがで
きる。According to this embodiment, it is possible to manufacture a lens having a small diameter at low cost and without wasting a material.

【００１５】[0015]

【実施例２】図３は、本実施例の光学素子の製造方法の
概略図を示すものであり、前述の実施例１と異なる点
は、上枠２と下枠３とを、ニクロム製にして、上下枠
２，３をヒータと兼用にした点であるから、他の同一部
材には同一番号を付しその説明を省略する。なお、図３
において、２ｂ，３ｂはヒータ用の導線である。[Embodiment 2] FIG. 3 shows a schematic view of a method for manufacturing an optical element of the present embodiment. The difference from Embodiment 1 is that the upper frame 2 and the lower frame 3 are made of nichrome. Since the upper and lower frames 2 and 3 are also used as the heaters, the same reference numerals are given to the other same members, and the description thereof will be omitted. Note that FIG.
In, 2b and 3b are conducting wires for the heater.

【００１６】上記構成によりレンズ１ａを製造する場合
を説明すると、まず、上枠２と下枠３の間にレンズ材料
１を挟持させる。次に通電して上下枠兼ニクロムヒータ
により、レンズ材料１を加熱し軟化させる。レンズ材料
１を６２０℃に加熱した後、上枠２と下枠３でレンズ材
料１を押圧して、上枠２と下枠３を当接させる。すると
上下枠２，３の穴２ａ，３ａから軟化したレンズ材料１
が押し出される。押し出されたレンズ材料１の曲率半径
Ｒが所望の値になったら、上下枠兼ニクロムヒータをＯ
ＦＦし硬化させる。上枠２と下枠３との間からレンズ１
ａを取り出し、外周は従来の加工技術により加工する。The case of manufacturing the lens 1a having the above-described structure will be described. First, the lens material 1 is sandwiched between the upper frame 2 and the lower frame 3. Next, the lens material 1 is heated and softened by applying electricity to the upper and lower frame / nichrome heaters. After heating the lens material 1 to 620 ° C., the lens material 1 is pressed by the upper frame 2 and the lower frame 3 to bring the upper frame 2 and the lower frame 3 into contact with each other. Then, the lens material 1 softened from the holes 2a and 3a of the upper and lower frames 2 and 3, respectively.
Is extruded. When the radius of curvature R of the extruded lens material 1 reaches a desired value, the upper and lower frames and nichrome heater are turned on.
FF and cure. The lens 1 from between the upper frame 2 and the lower frame 3
a is taken out, and the outer periphery is processed by the conventional processing technique.

【００１７】本実施例によれば、実施例１と同様の効果
が得られ、しかも上枠、下枠とヒータが一体である為に
構成が簡単になるという効果がある。According to this embodiment, the same effect as that of the first embodiment can be obtained, and further, the structure is simplified because the upper frame, the lower frame and the heater are integrated.

【００１８】[0018]

【実施例３】図４は、本実施例の光学素子の製造方法の
概略図を示すものであり、前述の実施例２と異なる点
は、上下枠兼ニクロムヒータ２，３をそのまま実装する
枠として使用する点であるから、他の同一部材には同一
番号を付しその説明を省略する。なお、図４において、
２ｃ，３ｃは上下枠兼ニクロムヒータ２，３に設けた枠
分割線である。また穴２ａ，３ａの径は、２mmに設定し
た。[Embodiment 3] FIG. 4 shows a schematic view of a method for manufacturing an optical element of the present embodiment. The difference from Embodiment 2 is that the upper and lower frames and nichrome heaters 2 and 3 are mounted as they are. Therefore, the same reference numerals are given to other same members, and the description thereof will be omitted. In addition, in FIG.
Reference numerals 2c and 3c are frame dividing lines provided on the upper and lower frame / nichrome heaters 2 and 3, respectively. The diameter of the holes 2a and 3a was set to 2 mm.

【００１９】前述の実施例２と同様な方法で、レンズ材
料１を所望の曲率半径Ｒに形成し硬化させる。しかる
後、上下兼用ニクロムヒータ２，３を枠分割線２ｃ，３
ｃで分割して、実装用枠付レンズ１ａを得た。The lens material 1 is formed to a desired radius of curvature R and cured in the same manner as in the second embodiment. Then, the upper and lower nichrome heaters 2 and 3 are attached to the frame dividing lines 2c and 3
Divided by c to obtain a mounting framed lens 1a.

【００２０】本実施例によれば、実施例２と同様の効果
が得られ、しかも枠からレンズを取り出したり、レンズ
の外周を加工する必要がなくなるという利点がある。According to this embodiment, the same effect as that of the second embodiment can be obtained, and there is an advantage that it is not necessary to take out the lens from the frame or process the outer circumference of the lens.

【００２１】[0021]

【発明の効果】以上のように、本発明の光学素子の製造
方法によれば、微小径のレンズを安価に、しかも素材を
無駄にすることなく製造することができる効果がある。As described above, according to the method of manufacturing an optical element of the present invention, there is an effect that a lens having a minute diameter can be manufactured at low cost and without waste of materials.

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

【図１】本発明にかかる光学素子の製造方法の概略図で
ある。FIG. 1 is a schematic view of a method for manufacturing an optical element according to the present invention.

【図２】本発明の実施例１の光学素子の製造方法の概略
図である。FIG. 2 is a schematic view of a method for manufacturing the optical element according to the first embodiment of the present invention.

【図３】本発明の実施例２の光学素子の製造方法の概略
図である。FIG. 3 is a schematic diagram of a method of manufacturing an optical element according to a second embodiment of the present invention.

【図４】本発明の実施例３の光学素子の製造方法の概略
図である。FIG. 4 is a schematic view of a method for manufacturing an optical element according to a third embodiment of the present invention.

【図５】従来の光学素子の製造方法の概略図である。FIG. 5 is a schematic view of a conventional method of manufacturing an optical element.

【符号の説明】[Explanation of symbols]

１ レンズ材料 ２ 上枠 ３ 下枠 ４ ヒータ １ａ レンズ ２ａ 穴 ３ａ 穴 1 Lens Material 2 Upper Frame 3 Lower Frame 4 Heater 1a Lens 2a Hole 3a Hole

Claims (1)

【特許請求の範囲】[Claims] 【請求項１】 円形の穴を有する上枠と下枠の間にレン
ズ材料を挟持させる工程と、ヒータにてレンズ材料を加
熱し軟化させる工程と、上枠と下枠を当接させ、レンズ
材料を上枠、下枠に有する穴から押し出す工程と、レン
ズ材料を硬化させる工程とから成ることを特徴とする光
学素子の製造方法。1. A step of sandwiching a lens material between an upper frame and a lower frame having circular holes, a step of heating and softening the lens material with a heater, and a step of bringing the upper frame and the lower frame into contact with each other to form a lens. A method of manufacturing an optical element, which comprises a step of extruding a material through holes provided in an upper frame and a lower frame, and a step of curing a lens material.
JP32244692A 1992-11-06 1992-11-06 Production of optical element Withdrawn JPH06144843A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP32244692A JPH06144843A (en) 1992-11-06 1992-11-06 Production of optical element

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP32244692A JPH06144843A (en) 1992-11-06 1992-11-06 Production of optical element

Publications (1)

Publication Number Publication Date
JPH06144843A true JPH06144843A (en) 1994-05-24

Family

ID=18143761

Family Applications (1)

Application Number Title Priority Date Filing Date
JP32244692A Withdrawn JPH06144843A (en) 1992-11-06 1992-11-06 Production of optical element

Country Status (1)

Country Link
JP (1) JPH06144843A (en)

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