JPS6347703A - Molding method for lens - Google Patents
Molding method for lensInfo
- Publication number
- JPS6347703A JPS6347703A JP19096386A JP19096386A JPS6347703A JP S6347703 A JPS6347703 A JP S6347703A JP 19096386 A JP19096386 A JP 19096386A JP 19096386 A JP19096386 A JP 19096386A JP S6347703 A JPS6347703 A JP S6347703A
- Authority
- JP
- Japan
- Prior art keywords
- molding material
- glass
- molding
- thin plate
- mold
- 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
Links
- 238000000465 moulding Methods 0.000 title claims description 34
- 238000000034 method Methods 0.000 title claims description 20
- 239000012778 molding material Substances 0.000 claims abstract description 60
- 239000011521 glass Substances 0.000 claims abstract description 54
- 230000002093 peripheral effect Effects 0.000 claims abstract description 12
- 230000007704 transition Effects 0.000 claims description 8
- 239000000463 material Substances 0.000 abstract description 19
- 239000005357 flat glass Substances 0.000 abstract description 10
- 238000010438 heat treatment Methods 0.000 abstract description 8
- 239000002184 metal Substances 0.000 abstract 3
- 239000012467 final product Substances 0.000 description 6
- 230000000694 effects Effects 0.000 description 5
- 239000000047 product Substances 0.000 description 5
- 230000001154 acute effect Effects 0.000 description 2
- 238000009826 distribution Methods 0.000 description 2
- 238000003825 pressing Methods 0.000 description 2
- 238000005452 bending Methods 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000004927 fusion Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 238000005498 polishing Methods 0.000 description 1
- 238000004904 shortening Methods 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
Landscapes
- Casting Or Compression Moulding Of Plastics Or The Like (AREA)
Abstract
Description
【発明の詳細な説明】
（技術分野）
本発明は、例えば非球面レンズの製作に適したレンズ成
形方法に関するものであり、特に、成形素材に対し薄板
ガラスを成形金型で加圧成形するようにしたレンズ成形
方法に関するものである。DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a lens molding method suitable for producing, for example, an aspherical lens. The present invention relates to a lens molding method.
（従来技術）
光学レンズ、特に非球面レンズ等を製造する方法として
、各種の高精度プレス成形法が提案されている。従来の
高精度プレスによるレンズ成形方法は、概ね、最終製品
に近い形に予備成形した成形素材を内部までほぼ均一に
転移点以上に加熱し、これを上記転移点以上に加熱した
金型によって成形するものである。(Prior Art) Various high-precision press molding methods have been proposed as methods for manufacturing optical lenses, especially aspherical lenses. Conventional lens molding methods using high-precision presses generally involve preforming a molding material into a shape close to the final product, heating it almost uniformly to a temperature above the transition point, and then molding it using a mold heated above the transition point. It is something to do.
しかし、このような従来のレンズ成形方法によれば、レ
ンズの所謂ヒケを防止するために、金型と成形品の温度
分布が均一になるように金型と成形品の温度を一定時間
以上保持する必要があり、また、プレス成形後の冷却過
程においても、プレス成形品を金型で保持した状態で、
温度分布が均一のまま転移点以下になるまで冷却する必
要がある。そのため、一つの金型による成形サイクルが
長くなって能率が悪く、また、成形品と金型との接触時
間が長いので金型が酸化され易く、金型の寿命が短いと
いう問題がある。However, according to such conventional lens molding methods, in order to prevent so-called sink marks on the lens, the temperature of the mold and molded product must be maintained for a certain period of time or longer to ensure uniform temperature distribution between the mold and molded product. Also, during the cooling process after press molding, the press molded product must be held in the mold.
It is necessary to cool down to below the transition point while maintaining a uniform temperature distribution. Therefore, there is a problem that the molding cycle using one mold becomes long, resulting in poor efficiency.Also, since the contact time between the molded product and the mold is long, the mold is easily oxidized, and the life of the mold is shortened.
かかる問題を解決する方法として、成形素材の温度を転
移点以下に保持し、成形素材と同質の軟化された薄板ガ
ラスで成形素材を挟み込み、これを成形素材に融着させ
てレンズを成形する方法も考えられている。One way to solve this problem is to maintain the temperature of the molding material below its transition point, sandwich the molding material between softened thin glass sheets of the same quality as the molding material, and fuse these to the molding material to form a lens. is also being considered.
また、これをさらに発展させ、成形素材と異質の薄板ガ
ラス、例えば成形素材の軟化点が６００℃とすると薄板
ガラスの素材として軟化点が４００℃のものを使用し、
もって、金型の温度をより低（することを可能にして金
型寿命を長（することを可能にしたレンズ成形方法も提
案されている。In addition, by further developing this, if the softening point of the molding material is 600°C, then a thin sheet glass different from the molding material, for example, a material with a softening point of 400°C is used as the material for the thin glass.
Accordingly, a lens molding method that makes it possible to lower the temperature of the mold and thereby extend the life of the mold has also been proposed.
しかし、このようなレンズ成形方法によれば、成形素材
と薄板ガラスとの温度差によって成形素材と薄板ガラス
とが融着しにり（、融着状態を強固にかつ確実に保持す
ることがで７〜ないという問題がある。However, according to such a lens molding method, the temperature difference between the molding material and the thin glass tends to cause the molding material and the thin glass to fuse (and it is not possible to firmly and reliably maintain the fused state). There is a problem that there is no 7.
（目的）
本発明の目的は、成形素材表面に薄板ガラスを加圧成形
するようにしたレン成形法において、仮に成形素材と薄
板ガラスとの間に大きな温度差があったとしても、成形
素材と薄板ガラスとの融着状態を強固にかつ確実に保持
することができるようにしたレンズ成形方法を提供する
ことにある。(Purpose) The purpose of the present invention is to use the lens forming method in which thin glass is pressure-formed on the surface of a forming material, even if there is a large temperature difference between the forming material and the thin glass. It is an object of the present invention to provide a lens molding method that can firmly and reliably maintain a fused state with a thin plate glass.
（構成）
本発明は、成形素材の有効口径外に周縁に沿って段部を
設け、成形素材に対し薄板ガラスを成形用金型で加圧成
形するとき薄板ガラスの周縁部を成形用金型で曲げて成
形素材の上記段部にかしめることを特徴とする。(Structure) The present invention provides a stepped portion along the periphery outside the effective aperture of the molding material, and when press-molding thin glass to the molding material with the molding die, the peripheral edge of the thin glass is placed in the molding die. It is characterized by bending the molded material and caulking it to the step part of the molded material.
以下、図面を参照しながら本発明に係るレンズ成形方法
の実施例を説明する。Embodiments of the lens molding method according to the present invention will be described below with reference to the drawings.
第１図は成形素材の一例を示す。第１図に示されている
成形素材１０はガラスにより最終製品に近い形に予備成
形され、有効口径外には周縁に沿い鋭角的に切り込まれ
ることにより段部１１が形成されている。成形素材１０
は、最終製品が非球面レンズの場合、この非球面に近似
の球面レンズとしてもよい。こうすることにより、成形
素材１０の製作には、粗研削−楕研削一研磨、というよ
うな従来から行われているレンズ成形法を用いることが
できる。FIG. 1 shows an example of a molded material. The molded material 10 shown in FIG. 1 is preformed from glass into a shape close to the final product, and a stepped portion 11 is formed outside the effective diameter by cutting at an acute angle along the periphery. Molding material 10
If the final product is an aspherical lens, it may be a spherical lens that approximates this aspherical surface. In this way, the molding material 10 can be manufactured using a conventional lens molding method such as rough grinding, elliptical grinding, and polishing.
上記成形素材１０はこれを同成形素材１０の材料の転移
点以下の温度に設定した炉に入れ、成形素材１０を内部
まで均一な温度になるように加熱する。The molding material 10 is placed in a furnace set at a temperature below the transition point of the material of the molding material 10, and heated to a uniform temperature throughout the molding material 10.
一方、第２図に示されている上金型１２及び下金型１３
の温度も成形素材１０の温度と同じになるように加熱し
ておく。上金型１２及び下金型１３は最終製品のレンズ
面と同様の曲面でなる加圧面１４．１５を有し、また、
上金型１２には加圧面１４の回りに突縁部１６が形成さ
れている。On the other hand, the upper mold 12 and the lower mold 13 shown in FIG.
The temperature of the molding material 10 is also heated to be the same as that of the molding material 10. The upper mold 12 and the lower mold 13 have pressing surfaces 14 and 15 which are curved surfaces similar to the lens surface of the final product, and
A projecting edge portion 16 is formed around the pressurizing surface 14 on the upper mold 12 .
第２図に示されているように、加熱された下金型１３の
加圧面１５には加熱された成形素材１０の下側の予備成
形面を嵌め、次いで、予め加熱炉で軟化点近くまで加熱
することにより軟化させた薄板ガラス１８を成形素材１
０の上に乗せる。薄板ガラス１８の外径は成形素材１０
の有効口径よりも大きく作られている。As shown in FIG. 2, the lower preformed surface of the heated molding material 10 is fitted into the pressure surface 15 of the heated lower mold 13, and then heated in a heating furnace until it reaches a temperature close to its softening point. A thin glass 18 softened by heating is formed into a molding material 1
Place it on top of 0. The outer diameter of the thin glass 18 is the molding material 10
It is made larger than the effective aperture of the
ここで、薄板ガラス１８の素材として軟化点が成形素材
１０の軟化点よりも低いものを選定することができる。Here, a material having a softening point lower than that of the molding material 10 can be selected as the material for the thin glass 18 .
その場合、成形素材ＩＯ１上下金型１２．１３及び薄板
ガラス１８の加熱温度は薄板ガラス１８の軟化点を基準
に同軟化点よりも低くかつ同軟化点に近い温度に設定す
る。In that case, the heating temperature of the upper and lower molds 12, 13 of the molding material IO1 and the thin glass 18 is set to a temperature lower than and close to the softening point of the thin glass 18, based on the softening point of the thin glass 18.
次に、第３図に示されているように上金型１２を降下さ
せ、上金型１２の加圧面１４により薄板ガラス１８を成
形素材１０に対して加圧成形する。このとき、薄板ガラ
ス１８の表面は上金型１２の加圧面１４の形に従って成
形され、よって、上金型１２の加圧面１４が非球面形状
であれば薄板ガラス１８の表面も上記非球面形状に従っ
て成形される。また、上金型１２の突縁部１６が薄板ガ
ラス１８の外周縁部を押して下方に折り曲げ、さらに上
記突縁部１６の内周壁１７が上記薄板ガラス１８の折り
曲げ部１９の外ｊ、１を規制し、もって、上記折り曲げ
部１９を成形素材ｌＯの段部１１の周囲に巻きつけるよ
うにしてかしめる。Next, as shown in FIG. 3, the upper mold 12 is lowered, and the pressing surface 14 of the upper mold 12 presses and forms the thin glass 18 against the molding material 10. At this time, the surface of the thin glass 18 is molded according to the shape of the pressure surface 14 of the upper mold 12. Therefore, if the pressure surface 14 of the upper mold 12 has an aspherical shape, the surface of the thin glass 18 also has the aspherical shape. Shaped according to. Further, the projecting edge 16 of the upper mold 12 presses the outer peripheral edge of the thin glass 18 and bends it downward, and furthermore, the inner peripheral wall 17 of the projecting edge 16 presses the outer peripheral edge of the thin glass 18 and bends the outer peripheral edge of the thin glass 18. Then, the bent portion 19 is wrapped around the stepped portion 11 of the molding material IO and crimped.
第４図は、以上のような工程を経て作られたレンズの最
終製品の例を示すものであり、薄板ガラス１８の外周縁
部が成形素材１０の段部１１にかしめられている。従っ
て、仮に成形素材１０の軟化点と薄板ガラス１８の軟化
点に大きな差があり、加熱温度を薄板ガラス１８の軟化
点以下に設定して成形しても、成形素材１０に対する薄
板ガラス１８の融着状態を強固にかつ確実に保持するこ
とができる。FIG. 4 shows an example of a final lens product made through the above-described steps, in which the outer peripheral edge of the thin glass 18 is caulked to the stepped portion 11 of the molding material 10. Therefore, even if there is a large difference between the softening point of the molding material 10 and the softening point of the thin glass 18, and the heating temperature is set below the softening point of the thin glass 18 for molding, the melting of the thin glass 18 relative to the molding material 10 will result. The attached state can be firmly and reliably maintained.
成形素材に形成する段部の断面形状は上記実施例のよう
に鋭角的な切り込みによって形成されるものに限られる
ものではなく、例えば、第５図に示されているように、
はぼ直角状の切り込みによって形成された段部２０でも
よく、この場合でも段部２０に対して薄板ガラス１８の
折り曲げ部１９がかしめられることにより成形素材１０
に対する薄板ガラス１８の融着状態を確実に保持するこ
とができる。The cross-sectional shape of the step formed in the molding material is not limited to that formed by an acute cut as in the above embodiment, but for example, as shown in FIG.
The stepped portion 20 may be formed by a substantially right-angled cut, and even in this case, the bent portion 19 of the thin glass 18 is caulked against the stepped portion 20, thereby forming the molding material 10.
The fused state of the thin glass plate 18 can be reliably maintained.
以上述べたような実施例によれば、薄板ガラス１８の軟
化点が低ければ低いほど有効であり、また成形素材１０
としては軟化点の高いものを使用することができる。例
えば、成形素材１０の軟化点が６００℃、薄板ガラス１
８の軟化点が４００℃とすると、成形素材１０、薄板ガ
ラス１８及び上下の金型１２．１３の加熱温度を薄板ガ
ラス１８の軟化点である４００℃以下に設定して成形し
ても、薄板ガラス１８の周縁部を成形素材１０の段部１
１にかしめることによって成形素材１０に対する薄板ガ
ラス１８の融着状態を強固にかつ確実に保持することが
できる。従って、成形素材１０の温度が転移点以上にな
ることはな（、よって、ヒケが発生することはない。According to the embodiments described above, the lower the softening point of the thin glass 18, the more effective it is;
A material having a high softening point can be used. For example, the softening point of the molding material 10 is 600°C, and the thin glass 1
8 has a softening point of 400°C, even if the heating temperature of the molding material 10, the thin glass 18, and the upper and lower molds 12.13 are set to below 400°C, which is the softening point of the thin glass 18, the thin plate The peripheral part of the glass 18 is connected to the step part 1 of the molding material 10.
By caulking the thin glass 18 to the molding material 10, the fused state of the thin glass 18 to the molding material 10 can be firmly and reliably maintained. Therefore, the temperature of the molding material 10 never exceeds the transition point (therefore, no sink marks occur).
一方、薄板ガラス１８は例えば上記のように４００℃近
くまで加熱することによってヒケが発生する要素がある
が、厚さが薄いためヒケの発生は僅かである。このよう
に、ヒケの要素が少ないことにより、成形時間を短くす
ることができるという効果をもたらす。On the other hand, although the thin glass 18 has some elements that cause sink marks when heated to nearly 400° C. as described above, the occurrence of sink marks is slight because the glass is thin. In this way, the reduction in the number of sink marks brings about the effect that the molding time can be shortened.
また、成形素材１０の軟化点が例えば６００℃であった
としても、薄板ガラス１８はその軟化点を例えば４００
℃というように成形素材１０の軟化点よりも低いものに
選定することにより、より低い成形温度で非球面等を成
形することができ、もって、金型の寿命が延びるという
効果がある。Further, even if the softening point of the molding material 10 is, for example, 600° C., the softening point of the thin glass 18 is, for example, 400° C.
By selecting a temperature lower than the softening point of the molding material 10, such as .degree. C., it is possible to mold an aspherical surface or the like at a lower molding temperature, which has the effect of extending the life of the mold.
上記のように、成形素材として軟化点が比較的高いもの
を使用することができるので、設計の自由度が増す。ま
た、金型の温度を低くすることができるので、金型材料
として一般の金型材のほかステンレス鋼等を使用するこ
とができる。As mentioned above, since a material with a relatively high softening point can be used as a molding material, the degree of freedom in design increases. Furthermore, since the temperature of the mold can be lowered, stainless steel or the like can be used in addition to general mold materials as the mold material.
図示の実施例では、レンズの片面のみを薄板ガラスの介
在の下に加圧成形するようにしていたが、レンズの両面
を薄板ガラスの介在の下に加圧成形するようにしてもよ
い。特にレンズの両面が非球面である場合には薄板ガラ
スの介在の下に加圧成形することが効果的である。また
、レンズ面は凸面に限られるものではなく、凹面であっ
てもよい。In the illustrated embodiment, only one side of the lens is pressure-molded with a thin plate of glass interposed, but both sides of the lens may be pressure-molded with a thin plate of glass interposed. Particularly when both surfaces of the lens are aspherical, it is effective to perform pressure molding with a thin plate of glass interposed. Further, the lens surface is not limited to a convex surface, but may be a concave surface.
加圧成形によって形成される面は、球面であってもよい
し、−船釣な意味での非球面であってもよく、円筒面で
あってもよい。The surface formed by pressure molding may be a spherical surface, an aspherical surface in the sense of boat fishing, or a cylindrical surface.
（効果）
本発明によれば、成形素材の有効口径外に周縁に沿って
段部を設け、成形素材に対し薄板ガラスを成形用金型で
加圧成形するとき薄板ガラスの周縁部を成形用金型で曲
げて成形素材の上記段部にかしめるようにしたため、成
形素材に対し薄板ガラスの融着状態が強固にかつ確実に
保持される。(Effects) According to the present invention, a stepped portion is provided along the periphery outside the effective aperture of the molding material, and when the thin glass is pressure-molded onto the molding material with a molding die, the periphery of the thin glass is used for molding. Since the sheet glass is bent with a mold and caulked onto the stepped portion of the molding material, the fused state of the thin glass sheet to the molding material is firmly and reliably maintained.
そのため、薄板ガラスの素材として軟化点の低いも゛の
を選定して金型温度を低くしても成形素材に対する薄板
ガラスの融着状態を確実に保持することができるから、
成形時間を短くすることができるし、金型の酸化による
劣化が少なくなるという効果を奏する。また、成形素材
としては軟化点の高いものを使用することができるから
、設計の自由度が増すという効果もある。Therefore, by selecting a material with a low softening point as the material for the thin glass, it is possible to reliably maintain the fusion state of the thin glass to the molding material even if the mold temperature is lowered.
This has the effect of shortening the molding time and reducing deterioration of the mold due to oxidation. Furthermore, since a material with a high softening point can be used as the molding material, there is also the effect of increasing the degree of freedom in design.
第１図は本発明に係るレンズ成形方法に用いられる成形
素材の一例を示す側面図、第２図は本発明に係るレンズ
成形方法の実施例の一工程を示す側面図、第３図は同じ
く他の工程を示す側面図、第４図は上記成形方法によっ
て作られる最終製品の例を示す側面図、第５図は本発明
に係るレンズ成形方法によって作られる最終製品の別の
例を示す側面図である。
１０・・・成形素材、 １１．２０・・・段部、１２．
１３・・・成形金型、 １８・・・薄板ガラス。FIG. 1 is a side view showing an example of the molding material used in the lens molding method according to the present invention, FIG. 2 is a side view showing one step of the embodiment of the lens molding method according to the present invention, and FIG. 3 is the same. FIG. 4 is a side view showing another example of the final product made by the above molding method; FIG. 5 is a side view showing another example of the final product made by the lens molding method according to the present invention. It is a diagram. 10...Molding material, 11.20...Step part, 12.
13... Molding mold, 18... Thin glass.
Claims (1)
材の転移点温度以下に保たれた成形金型で軟化した薄板
ガラスを成形素材に加圧成形するようにしたレンズ成形
方法において、成形素材の有効口径外に周縁に沿って段
部を設け、成形素材に対し薄板ガラスを成形用金型で加
圧成形するとき薄板ガラスの周縁部を成形用金型で曲げ
て成形素材の上記段部にかしめることを特徴とするレン
ズ成形方法。In a lens molding method, the entire molding material is heated to a temperature below the transition point temperature, and then the softened thin glass is pressure-molded onto the molding material using a molding die maintained at a temperature below the transition point temperature of the molding material. A step is provided along the periphery outside the effective aperture of the molding material, and when the thin glass is pressure-molded onto the molding material using the molding die, the peripheral edge of the thin glass is bent with the molding mold to remove the stepped portion of the molding material. A lens forming method characterized by caulking.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP19096386A JPS6347703A (en) | 1986-08-14 | 1986-08-14 | Molding method for lens |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP19096386A JPS6347703A (en) | 1986-08-14 | 1986-08-14 | Molding method for lens |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS6347703A true JPS6347703A (en) | 1988-02-29 |
Family
ID=16266586
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP19096386A Pending JPS6347703A (en) | 1986-08-14 | 1986-08-14 | Molding method for lens |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6347703A (en) |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5749526A (en) * | 1980-09-08 | 1982-03-23 | Olympus Optical Co Ltd | Molding and correction of plastic lens |
| JPS60205402A (en) * | 1984-03-29 | 1985-10-17 | Audio Technica Corp | Hybrid lens |
-
1986
- 1986-08-14 JP JP19096386A patent/JPS6347703A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5749526A (en) * | 1980-09-08 | 1982-03-23 | Olympus Optical Co Ltd | Molding and correction of plastic lens |
| JPS60205402A (en) * | 1984-03-29 | 1985-10-17 | Audio Technica Corp | Hybrid lens |
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