JP2610040B2 - Manufacturing method of optical fiber preform - Google Patents
Manufacturing method of optical fiber preformInfo
- Publication number
- JP2610040B2 JP2610040B2 JP63291983A JP29198388A JP2610040B2 JP 2610040 B2 JP2610040 B2 JP 2610040B2 JP 63291983 A JP63291983 A JP 63291983A JP 29198388 A JP29198388 A JP 29198388A JP 2610040 B2 JP2610040 B2 JP 2610040B2
- Authority
- JP
- Japan
- Prior art keywords
- optical fiber
- fiber preform
- deposition layer
- particle deposition
- glass
- 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
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B37/00—Manufacture or treatment of flakes, fibres, or filaments from softened glass, minerals, or slags
- C03B37/01—Manufacture of glass fibres or filaments
- C03B37/012—Manufacture of preforms for drawing fibres or filaments
- C03B37/014—Manufacture of preforms for drawing fibres or filaments made entirely or partially by chemical means, e.g. vapour phase deposition of bulk porous glass either by outside vapour deposition [OVD], or by outside vapour phase oxidation [OVPO] or by vapour axial deposition [VAD]
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Manufacture, Treatment Of Glass Fibers (AREA)
Description
【発明の詳細な説明】 ［産業上の利用分野］ 本発明は、光ファイバ母材の製造方法に関するもので
ある。The present invention relates to a method for producing an optical fiber preform.
［従来技術］ 従来の光ファイバ母材の製造は、第２図に示すように
堆積室１の長手方向の両端寄りの給気口2A,2Bから給気
し、長手方向の中央の排気口３から排気しつつ、該堆積
室１内でコア又はコアと一部のクラッドからなる脱水，
ガラス化された棒状の光ファイバ母材基体４を回転させ
つつその軸心方向に往復移動させ、バーナ５で光ファイ
バ母材基体４の外周にガラス微粒子を吹付けてガラス微
粒子堆積層６を形成し、得られた光ファイバ母材中間体
７を取出してガラス微粒子堆積層６の脱水，ガラス化す
ることにより行っていた。[Prior Art] In the conventional production of an optical fiber preform, as shown in FIG. 2, air is supplied from air supply ports 2A and 2B near both ends in the longitudinal direction of a deposition chamber 1 and an exhaust port 3 in the center in the longitudinal direction. Dewatering of the core or the core and a part of the cladding in the deposition chamber 1
The vitrified rod-shaped optical fiber preform base 4 is reciprocated in the axial direction while rotating, and the burner 5 sprays glass fines around the optical fiber preform base 4 to form a glass fines deposition layer 6. Then, the obtained optical fiber preform intermediate 7 is taken out, and the glass fine particle deposition layer 6 is dehydrated and vitrified.
この場合、クラッドとなるガラス微粒子堆積層６の厚
さは、コア径とクラッド径の比が所望の値となるように
制御する必要がある。In this case, it is necessary to control the thickness of the glass particle deposition layer 6 serving as the clad so that the ratio of the core diameter to the clad diameter becomes a desired value.
従来は、光ファイバ母材を作る中間段階の製品である
ガラス微粒子堆積層６の厚さを制御して最終的なコア／
クラッド径比を所望の値にすることが困難なため、光フ
ァイバ母材中間体７の形成後に、脱水，ガラス化してコ
ア／クラッド径比を測定し、所望の値が得られていない
場合には、エッチングしてクラッド径を小さくしたり、
或いは逆に再度不足分のガラス微粒子堆積層を形成し、
脱水，ガラス化してクラッド径を大きくしたりして調節
していた。Conventionally, the thickness of the glass fine particle deposition layer 6, which is an intermediate product for producing an optical fiber preform, is controlled to obtain a final core /
Since it is difficult to set the clad diameter ratio to a desired value, the core / clad diameter ratio is measured after dehydration and vitrification after the formation of the optical fiber preform intermediate 7, and if the desired value is not obtained, Can be etched to reduce clad diameter,
Or, conversely, a glass fine particle deposition layer of insufficient amount is formed again,
Dehydration and vitrification were used to increase the cladding diameter.
［発明が解決しようとする課題］ しかしながら、このような光ファイバ母材の製造方法
では、光ファイバ母材の外径の再調節工程の付加によ
り、歩留りが悪く、光ファイバの製造コストが高くなる
と共に通常の倍以上の製造時間を要するという問題点が
あった。[Problems to be Solved by the Invention] However, in such a method of manufacturing an optical fiber preform, the yield is poor and the manufacturing cost of the optical fiber is increased due to the addition of the step of adjusting the outer diameter of the optical fiber preform. In addition, there is a problem that the production time is required to be twice or more than usual.
本発明の目的は、外径の再調節工程を省略して能率よ
く低コストで製造ができる光ファイバ母材の製造方法を
提供することにある。An object of the present invention is to provide a method of manufacturing an optical fiber preform that can be manufactured efficiently and at low cost by omitting a step of adjusting the outer diameter.
［課題を解決するための手段］ 上記の目的を達成するための本発明の手段を説明する
と、本発明はコア又はコアと一部のクラッドからなる脱
水，ガラス化された棒状の光ファイバ母材基体の外周に
ガラス微粒子を吹付けてガラス微粒子堆積層を設けるこ
とにより光ファイバ母材中間体を形成し、該光ファイバ
母材中間体の前記ガラス微粒子堆積層の脱水，ガラス化
を行って光ファイバ母材を得る光ファイバ母材の製造方
法において、前記ガラス微粒子堆積層の外径及び重量を
測定することにより前記ガラス微粒子堆積層の単位長さ
当りの重量を求め、この値が所望の値となるまで前記ガ
ラス微粒子の堆積を行うことを特徴とする。Means for Solving the Problems The means of the present invention for achieving the above object will be described. The present invention provides a dehydrated and vitrified rod-shaped optical fiber preform comprising a core or a core and a part of a clad. An optical fiber preform intermediate is formed by spraying glass fine particles on the outer periphery of the substrate to form a glass fine particle deposition layer, and dehydrating and vitrifying the glass fine particle deposition layer of the optical fiber preform intermediate to form a light beam. In the method of manufacturing an optical fiber preform to obtain a fiber preform, the weight per unit length of the glass fine particle deposition layer is determined by measuring the outer diameter and weight of the glass fine particle deposition layer, and this value is a desired value. The method is characterized in that the glass fine particles are deposited until the following conditions are satisfied.
［作用］ ガラス微粒子堆積層を脱水，ガラス化した後の光ファ
イバ母材の径は、ガラス微粒子堆積層の外径と共にその
密度も大きく影響するという観点から、ガラス微粒子の
堆積工程でガラス微粒子堆積層の外径と同時にその重量
を測定してガラス化後の外径を推定するための実験を重
ねた。[Operation] The diameter of the optical fiber preform after the glass fine particle deposition layer is dehydrated and vitrified greatly affects not only the outer diameter of the glass fine particle deposition layer but also its density. Experiments were repeated to estimate the outer diameter after vitrification by measuring the weight at the same time as the outer diameter of the layer.
その結果、単位長さ当りのガラス微粒子堆積層の重量
と、これをガラス化した後の光ファイバ母材の外径とは
一定の関係にあり、これに基いてコア／クラッド径比を
十分制御できることが判明した。従って、ガラス微粒子
堆積層の単位長さ当りの重量を求め、この値が所望の値
になるまでガラス微粒子の堆積を行うと、光ファイバ母
材を作る最終工程でその外径の再調整を行う必要がなく
なる。また、この単位長さ当りのガラス微粒子堆積層の
重量と光ファイバ母材の外径との関係は、ガラス微粒子
堆積層の外径の違いに関係なく一定であるため、ガラス
微粒子堆積層の密度を綿密に制御する必要がない。As a result, the weight of the glass particle deposition layer per unit length and the outer diameter of the optical fiber preform after vitrification have a fixed relationship, and the core / cladding diameter ratio is sufficiently controlled based on this. It turns out that it can be done. Therefore, when the weight per unit length of the glass fine particle deposition layer is obtained and the glass fine particles are deposited until this value becomes a desired value, the outer diameter is readjusted in the final step of producing the optical fiber preform. Eliminates the need. Since the relationship between the weight of the glass particle deposition layer per unit length and the outer diameter of the optical fiber preform is constant regardless of the difference in the outer diameter of the glass particle deposition layer, the density of the glass particle deposition layer is constant. There is no need for close control.
［実施例］ 以下、本発明の実施例を第１図（Ａ）（Ｂ）を参照し
て詳細に説明する。なお、図において、前述した第２図
と対応する部分には、同一符号を付けて示している。本
実施例では、第２図に示すようにして光ファイバ母材中
間体７を製造する過程で、ガラス微粒子堆積層６の外径
Ｄを外径測定器（例えば、市販のレーザ外径測定器を使
用する。）で連続的に又は断続的に測定する。また、該
ガラス微粒子堆積層６の長手方向寸法を、該ガラス微粒
子堆積層６とバーナ５との相対移動距離L1及び経験値で
得られたテーパ部長さL2から（L1＋L2）として求める。
なお、第１図において、ｄは光ファイバ母材基体４の外
径である。これらのデータをもとに、図示しない制御装
置の演算部でガラス微粒子堆積層６の体積Ｖ（cm3）を
求める。Embodiment An embodiment of the present invention will be described below in detail with reference to FIGS. 1 (A) and 1 (B). In the figure, parts corresponding to those in FIG. 2 described above are denoted by the same reference numerals. In this embodiment, in the process of manufacturing the optical fiber preform intermediate 7 as shown in FIG. 2, the outer diameter D of the glass fine particle deposition layer 6 is measured with an outer diameter measuring instrument (for example, a commercially available laser outer diameter measuring instrument). Is measured continuously or intermittently. The longitudinal dimension of the glass particle deposition layer 6 is defined as (L 1 + L 2 ) based on the relative movement distance L 1 between the glass particle deposition layer 6 and the burner 5 and the length L 2 of the tapered portion obtained from empirical values. Ask.
In FIG. 1, d is the outer diameter of the optical fiber preform base 4. Based on these data, a volume V (cm 3 ) of the glass fine particle deposition layer 6 is obtained by an arithmetic unit of a control device (not shown).
また、ガラス微粒子堆積層６の重量Ｗ（ｇ）を重量測
定器（例えば、ロードセルを使用する。）で連続的又は
断続的に測定する。このとき、光ファイバ母材基体４の
重量も加味した重さが測定されるので、測定重量から該
光ファイバ母材基体４の重量を除去する。Further, the weight W (g) of the glass fine particle deposition layer 6 is measured continuously or intermittently by a weight measuring device (for example, using a load cell). At this time, since the weight is measured in consideration of the weight of the optical fiber preform base 4, the weight of the optical fiber preform base 4 is removed from the measured weight.
次に、ガラス微粒子堆積層６の平均密度ρ＝W/V（g/c
m3）を求める。Next, the average density ρ = W / V (g / c
m 3 ).
次に、光ファイバ母材基体４の外径ｄとガラス微粒子
堆積層６の外径Ｄとからガラス微粒子堆積層６の断面積
ＡをＡ＝π（D2−d2）/4（cm2）より求める。Next, based on the outer diameter d of the optical fiber preform base 4 and the outer diameter D of the glass fine particle deposition layer 6, the sectional area A of the glass fine particle deposition layer 6 is calculated as A = π (D 2 −d 2 ) / 4 (cm 2 ). ).
次に、ガラス微粒子堆積層６の単位長さ当りの重量ｗ
＝ρ×Ａ（g/cm）を求める。Next, the weight w per unit length of the glass particle deposition layer 6
= Ρ × A (g / cm).
このガラス微粒子堆積層６の単位長さ当りの重量ｗ
と、第１図（Ｂ）に示すガラス微粒子堆積層６を脱水，
ガラス化して得た光ファイバ母材８におけるガラス層6A
の外径（Ｄ′−ｄ）との間には一定の関係があるので、
ガラス微粒子堆積層６の単位長さ当りの重量ｗが所望の
値になった時点で堆積を停止する。The weight w per unit length of the glass particle deposition layer 6
The glass fine particle deposition layer 6 shown in FIG.
Glass layer 6A in optical fiber preform 8 obtained by vitrification
Since there is a certain relationship with the outer diameter (D'-d) of
The deposition is stopped when the weight w per unit length of the glass particle deposition layer 6 reaches a desired value.
ガラス微粒子堆積層６の単位長さ当りの重量ｗの目標
値は、予め実験で得られた関係式から所定のコア／クラ
ッド径比を得るのに必要な（Ｄ′−ｄ）より求めて、制
御装置内に予め入力しておく。The target value of the weight w per unit length of the glass particle deposition layer 6 is obtained from (D'-d) necessary to obtain a predetermined core / cladding diameter ratio from a relational expression obtained in advance by an experiment. It is input in the control device in advance.
このようにして光ファイバ母材中間体７を得ると、ガ
ラス化後に外径の再調整を行う必要がなくなる。When the optical fiber preform intermediate 7 is thus obtained, it is not necessary to readjust the outer diameter after vitrification.
上記実施例では、各光ファイバ母材中間体製造設備に
それぞれ外径，重量測定器を設けることになるので、設
備台数が多い場合、設備コストがかさむ。そこで、測定
器は全設備共有のものを一式設け、下記のようにして使
用すると、設備コストを低減できる。即ち、変動分を含
めて若干小さめのガラス微粒子堆積層６を作製し、一旦
これを設備から取り外し、外径，重量を測定の上、単位
長さ当りの重量を計算する。得られた値を目標値から差
引いて、不足分を割り出し、これに相当するガラス微粒
子の合成回数又は時間の分、ガラス微粒子の再合成を行
う。In the above embodiment, an outer diameter and a weight measuring device are provided in each of the optical fiber preform intermediate production facilities, so that when the number of facilities is large, the facility cost increases. Therefore, if a set of measuring instruments common to all facilities is provided and used as described below, facility costs can be reduced. That is, a slightly smaller glass fine particle deposition layer 6 including the variation is produced, temporarily removed from the equipment, the outer diameter and the weight are measured, and the weight per unit length is calculated. The obtained value is subtracted from the target value to determine the shortage, and the glass fine particles are re-synthesized according to the number of times or the time for synthesizing the glass fine particles.
また、ガラス微粒子堆積層６の外径Ｄは、実際には長
手方向にいく分変動しているので、連続した外径プロフ
ァイルの測定、若しくは長手方向多点測定で変動分を加
味することにより、更に正確なガラス微粒子堆積６の体
積が算出されるためρ×ＡとＤ′−ｄの関係精度を向上
させることができる。Further, since the outer diameter D of the glass fine particle deposition layer 6 actually fluctuates somewhat in the longitudinal direction, by measuring the continuous outer diameter profile or by taking into account the fluctuation in the longitudinal multipoint measurement, Further, since the volume of the glass particle deposition 6 is calculated more accurately, the accuracy of the relationship between ρ × A and D′−d can be improved.
更に、ガラス微粒子堆積層６の密度も制御したい場合
は、逐次密度も演算検出し、これが所望の値となるため
に加熱温度等の制御により密度コントロールも実現でき
る。同時に、ガラス微粒子堆積層６の単位長さ当りの重
量を制限することで、コア／クラッド径比も制御でき
る。Furthermore, when it is desired to control the density of the glass fine particle deposition layer 6, the density is also calculated and detected sequentially, and since this becomes a desired value, the density control can be realized by controlling the heating temperature and the like. At the same time, the core / cladding diameter ratio can be controlled by limiting the weight per unit length of the glass particle deposition layer 6.
［発明の効果］ 以上説明したように本発明に係る光ファイバ母材の製
造方法は、ガラス微粒子堆積層の合成段階でその単位長
さ当りの重量を求め、この値が所望の値になるまでガラ
ス微粒子の堆積を行うので、多大の時間とコストを要す
るガラス化後の再調節（エッチングによる削除、再合
成、ガラス化による付加）が不要になる利点がある。ま
た、ガラス微粒子堆積層の密度の制約が少ない場合は、
密度が変動してもコア／クラッド径比の制御が可能なた
め、密度の高精度の制御が不要になる利点がある。即
ち、設備の制御精度，経時変化の影響を受けずにコア／
クラッド径比が制御できる利点がある。更に、本発明に
よれば、コア／クラッド径比と共にガラス微粒子堆積層
の密度の制御も必要に応じてできる利点がある。[Effects of the Invention] As described above, in the method for manufacturing an optical fiber preform according to the present invention, the weight per unit length is determined at the stage of synthesizing the glass fine particle deposition layer, and until the value becomes a desired value. Since glass fine particles are deposited, there is an advantage that readjustment (deletion by etching, resynthesis, addition by vitrification) after vitrification, which requires a great deal of time and cost, is not required. In addition, when there is little restriction on the density of the glass particle deposition layer,
Since the core / cladding diameter ratio can be controlled even when the density fluctuates, there is an advantage that high-precision control of the density becomes unnecessary. In other words, the core /
There is an advantage that the clad diameter ratio can be controlled. Further, according to the present invention, there is an advantage that the control of the density of the glass particle deposition layer together with the core / cladding diameter ratio can be performed as required.
第１図（Ａ）（Ｂ）は本発明に係る光ファイバ母材の製
造方法の製造過程を示す縦断面図、第２図は光ファイバ
母材の製造方法におけるガラス微粒子の堆積工程の断面
図である。 １……堆積室、2A,2B……給気口、３……排気口、４…
…光ファイバ母材基体、５……バーナー、６……ガラス
微粒子堆積層、6A……ガラス層、７……光ファイバ母材
中間体、８……光ファイバ母材。1 (A) and 1 (B) are longitudinal sectional views showing a production process of a method for producing an optical fiber preform according to the present invention, and FIG. 2 is a sectional view showing a step of depositing glass fine particles in the method for producing an optical fiber preform. It is. 1 ... deposition chamber, 2A, 2B ... air supply port, 3 ... exhaust port, 4 ...
... optical fiber preform base material, 5 ... burner, 6 ... glass fine particle deposition layer, 6A ... glass layer, 7 ... optical fiber preform intermediate material, 8 ... optical fiber preform.
Claims (1)
水，ガラス化された棒状の光ファイバ母材基体の外周に
ガラス微粒子を吹付けてガラス微粒子堆積層を設けるこ
とにより光ファイバ母材中間体を形成し、該光ファイバ
母材中間体の前記ガラス微粒子堆積層の脱水，ガラス化
を行って光ファイバ母材を得る光ファイバ母材の製造方
法において、前記ガラス微粒子堆積層の外径及び重量を
測定することにより前記ガラス微粒子堆積層の単位長さ
当りの重量を求め、この値が所望の値となるまで前記ガ
ラス微粒子の堆積を行うことを特徴とする光ファイバ母
材の製造方法。An intermediate layer of an optical fiber preform is provided by spraying glass microparticles on an outer periphery of a dehydrated and vitrified rod-shaped optical fiber preform base comprising a core or a core and a part of a clad to provide a glass particle deposition layer. A method for producing an optical fiber preform by forming a body and dehydrating and vitrifying the glass fine particle deposition layer of the optical fiber preform intermediate to obtain an optical fiber preform. A method for producing an optical fiber preform, characterized in that a weight per unit length of the glass fine particle deposition layer is obtained by measuring a weight, and the glass fine particles are deposited until this value becomes a desired value.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63291983A JP2610040B2 (en) | 1988-11-18 | 1988-11-18 | Manufacturing method of optical fiber preform |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63291983A JP2610040B2 (en) | 1988-11-18 | 1988-11-18 | Manufacturing method of optical fiber preform |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH02137743A JPH02137743A (en) | 1990-05-28 |
| JP2610040B2 true JP2610040B2 (en) | 1997-05-14 |
Family
ID=17775994
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63291983A Expired - Lifetime JP2610040B2 (en) | 1988-11-18 | 1988-11-18 | Manufacturing method of optical fiber preform |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2610040B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| AU774859B2 (en) | 2000-10-30 | 2004-07-08 | Sumitomo Electric Industries, Ltd. | Method of manufacturing optical fiber preform |
| CN107255602B (en) * | 2017-06-06 | 2020-05-05 | 武汉烽火锐拓科技有限公司 | Method and device for on-line measuring density of loose body |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS57183330A (en) * | 1981-04-30 | 1982-11-11 | Nippon Sheet Glass Co Ltd | Production of basic material for optical-communication glass fiber |
| JPS61201638A (en) * | 1985-03-04 | 1986-09-06 | Sumitomo Electric Ind Ltd | Production of high-purity glass body |
| US4810276A (en) * | 1987-08-05 | 1989-03-07 | Corning Glass Works | Forming optical fiber having abrupt index change |
-
1988
- 1988-11-18 JP JP63291983A patent/JP2610040B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH02137743A (en) | 1990-05-28 |
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