JPS6170437A - Method for measuring wavelength dispersion of optical fiber - Google Patents
Method for measuring wavelength dispersion of optical fiberInfo
- Publication number
- JPS6170437A JPS6170437A JP19293984A JP19293984A JPS6170437A JP S6170437 A JPS6170437 A JP S6170437A JP 19293984 A JP19293984 A JP 19293984A JP 19293984 A JP19293984 A JP 19293984A JP S6170437 A JPS6170437 A JP S6170437A
- Authority
- JP
- Japan
- Prior art keywords
- fiber
- optical fiber
- geo2
- fibers
- measuring
- 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
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M11/00—Testing of optical apparatus; Testing structures by optical methods not otherwise provided for
- G01M11/30—Testing of optical devices, constituted by fibre optics or optical waveguides
- G01M11/33—Testing of optical devices, constituted by fibre optics or optical waveguides with a light emitter being disposed at one fibre or waveguide end-face, and a light receiver at the other end-face
- G01M11/338—Testing of optical devices, constituted by fibre optics or optical waveguides with a light emitter being disposed at one fibre or waveguide end-face, and a light receiver at the other end-face by measuring dispersion other than PMD, e.g. chromatic dispersion
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M11/00—Testing of optical apparatus; Testing structures by optical methods not otherwise provided for
- G01M11/30—Testing of optical devices, constituted by fibre optics or optical waveguides
- G01M11/33—Testing of optical devices, constituted by fibre optics or optical waveguides with a light emitter being disposed at one fibre or waveguide end-face, and a light receiver at the other end-face
- G01M11/332—Testing of optical devices, constituted by fibre optics or optical waveguides with a light emitter being disposed at one fibre or waveguide end-face, and a light receiver at the other end-face using discrete input signals
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M11/00—Testing of optical apparatus; Testing structures by optical methods not otherwise provided for
- G01M11/30—Testing of optical devices, constituted by fibre optics or optical waveguides
- G01M11/33—Testing of optical devices, constituted by fibre optics or optical waveguides with a light emitter being disposed at one fibre or waveguide end-face, and a light receiver at the other end-face
- G01M11/335—Testing of optical devices, constituted by fibre optics or optical waveguides with a light emitter being disposed at one fibre or waveguide end-face, and a light receiver at the other end-face using two or more input wavelengths
Landscapes
- Physics & Mathematics (AREA)
- Chemical & Material Sciences (AREA)
- Optics & Photonics (AREA)
- Analytical Chemistry (AREA)
- General Physics & Mathematics (AREA)
- Dispersion Chemistry (AREA)
- Light Guides In General And Applications Therefor (AREA)
Abstract
Description
【発明の詳細な説明】
（産業上の利用分野）
本発明の波長分散測定方法はＹＡＧレーザによるＧｅ０
２２アイバラマンレーザを用いて光ファイバの波長分散
を測定するものである。Detailed Description of the Invention (Industrial Application Field) The chromatic dispersion measurement method of the present invention uses a YAG laser to measure Ge0
The chromatic dispersion of an optical fiber is measured using a .22 Brassian laser.
（従来技術）
波長分散測定系として従来は第３図に示すようなものが
ある。これは石英ファイバ（Ｓｉ０２）を用いてラマン
散乱を励起させるものである。ｆｉｒＪ３図のＡは励起
用光源であり、Ｑスイッチ及びモードロック動作の可能
なＮｄ ： ＹＡＧレーザが使用されている。(Prior Art) There is a conventional wavelength dispersion measuring system as shown in FIG. This uses a quartz fiber (Si02) to excite Raman scattering. A in the firJ3 diagram is an excitation light source, and an Nd:YAG laser capable of Q-switching and mode-locking operation is used.
この測定系では、励起用の単一モード光ファイバＢから
の出力光を分光器Ｃで波長選択し、ついで分光後の出力
をＡＰＤ（７バランシユホトダイオード）で受信し、そ
れを増幅器りで増幅して高速のオシロスコープＥで観測
するようにしである第３図の測定系で単一モード光ファ
イバＡの伝搬遅延時間を測定するには以下の手順により
行なう。In this measurement system, a spectrometer C selects the wavelength of the output light from a single mode optical fiber B for pumping, the output after spectroscopy is then received by an APD (7 balance photodiode), and it is amplified by an amplifier. In order to measure the propagation delay time of the single mode optical fiber A using the measurement system shown in FIG. 3, which is to be observed using a high-speed oscilloscope E, the following procedure is used.
まず、励起用光ファイバＢについて伝搬遅延時間差の波
長依存性の測定を行なう、ついで励起用光ファイバＢに
被測定用光ファイバＦを接続し、同様に伝搬遅延時間差
の波長依存性の測定する。First, the wavelength dependence of the propagation delay time difference is measured for the pumping optical fiber B. Next, the optical fiber F to be measured is connected to the pumping optical fiber B, and the wavelength dependence of the propagation delay time difference is similarly measured.
被測定用光ファイバＦの伝搬遅延時間差は、接続後の遅
延時間から励起用光ファイバＢの遅延時間を差引くこと
により決定する。The propagation delay time difference of the optical fiber to be measured F is determined by subtracting the delay time of the pumping optical fiber B from the delay time after connection.
第２図に示すものは５ｉ０２ファイバラマンレ−ザの典
型的な分光特性例を示すものである。波長１．１２４ｍ
、１．１８ｇｍ、１．２４ｇｍ及び１．３１ｐｍに観測
されるピークは、夫々５ｉ−Ｏ−５ｉ結合の分子振動に
よるラマン散乱の第１ストークス光から第４ストークス
光に相当する（発明が解決しようとする問題点）
イ、８３図に示すものは５ｉ０２フアイ／へを使用する
ものであるため分光特性が第２図に示すようになる。そ
のため分光器Ｃを使って波長選択（掃引）を行なわなけ
ればならない、この場合、分光器Ｃの波長分解能を得る
ため分光器Ｃのスリットを拡げれば分散によってパルス
波形の広がりが太き、くなり、パルスピークによる遅延
時間の測定誤差が大きくなるためスリットを絞らなけれ
ばならない、しかし分光器Ｃのスリットを絞ると出力パ
ワーが下り、測定ダイナミックレンジが小さくなる。測
定ダイナミックレンジが小さくなると高精度の測定がむ
ずかしくなるため、分光器Ｃを使用する場合はスリット
の絞り度合を波長分解能（精度）とダイナミックレンジ
を考慮して最適化しなければならない。What is shown in FIG. 2 shows an example of typical spectral characteristics of a 5i02 fiber Raman laser. Wavelength 1.124m
The peaks observed at , 1.18 gm, 1.24 gm, and 1.31 pm correspond to the first to fourth Stokes lights of Raman scattering due to the molecular vibration of the 5i-O-5i bond (this invention will solve the problem). (2) Since the one shown in Fig. 83 uses a 5i02 fiber, the spectral characteristics are as shown in Fig. 2. Therefore, wavelength selection (sweeping) must be performed using spectrometer C. In this case, if the slit of spectrometer C is widened in order to obtain the wavelength resolution of spectrometer C, the pulse waveform will widen due to dispersion. Therefore, the measurement error in the delay time due to the pulse peak increases, so the slit must be narrowed down.However, when the slit of the spectrometer C is narrowed down, the output power decreases and the measurement dynamic range becomes smaller. As the measurement dynamic range becomes smaller, highly accurate measurement becomes difficult, so when using the spectrometer C, the degree of aperture of the slit must be optimized in consideration of wavelength resolution (accuracy) and dynamic range.
０．５ｉ０２フアイバを使用した場合、１．３ＪＬｍ波
長近傍のラマン散乱出力が弱い。When a 0.5i02 fiber is used, the Raman scattering output near the 1.3JLm wavelength is weak.
ハ９分光特性が第２図に示すように連続的になるため分
光器Ｃで分光しなければんらす、測定に時間がかかる。C9 Since the spectral characteristics are continuous as shown in FIG. 2, the spectrometer C must be used to perform the spectroscopic analysis, which takes time to measure.
（問題を解決するための手段）
本発明の目的は波長分数の測定精度を保ちながら（従来
と比べて）測定ダイナミックレンジを大幅に向上させ、
しかも測定時間を短縮することにある。(Means for Solving the Problem) The purpose of the present invention is to significantly improve the measurement dynamic range (compared to conventional methods) while maintaining the measurement accuracy of wavelength fractions.
Moreover, the aim is to shorten the measurement time.
そのため本発明では励起用光ファイバとしてＧｅＯ２フ
ァイバを使用するようにしである。Therefore, in the present invention, a GeO2 fiber is used as the excitation optical fiber.
本発明の測定系を第１図に示す、この測定系はＱスイッ
チ及びモードロック動作の可能なＮｄ：ＹＡＧレーザに
よる励起用光源ｌからのレーザをＧｅＯ２ファイバによ
る励起用光ファイバ２に入射して第４図に示すような分
光特性のＧｅｍ２フアイバラマンレーザを得る。The measurement system of the present invention is shown in FIG. 1. This measurement system injects a laser beam from an excitation light source 1, which is a Nd:YAG laser capable of Q-switching and mode-locking operation, into an excitation optical fiber 2, which is a GeO2 fiber. A Gem2 fiber Brahman laser having spectral characteristics as shown in FIG. 4 is obtained.
このレーザを光学的バンドフィルターまたは簡易タイプ
の回折格子３で各ストーク光を分離して被測定用ファイ
バ４に入射し、同ファイバ４からの出力光をアバランシ
ュホトダイオードＡＰＤで検出し、高速のオシロスコー
プ５で観測するようにしたものである。This laser is separated into individual stalk lights using an optical band filter or a simple type diffraction grating 3, and then inputted into a fiber 4 to be measured.The output light from the fiber 4 is detected by an avalanche photodiode APD, and a high-speed oscilloscope 5 It was designed to be observed.
（実験例）
第１図の測定系を用いて３．９６ｋｍのシングルモード
ファイバの波長分散を測定した０本実験で用いたＧｅｍ
、ファイバの諸元は次の通りである。(Experiment example) Gem used in the experiment in which the wavelength dispersion of a 3.96 km single mode fiber was measured using the measurement system shown in Figure 1.
, the specifications of the fiber are as follows.
ｓｂドープのＧｅＯ２コア、直径ニア０４ｍ純ＧｅＯ２
クラッド、 直径：１５０ｇｍ開口比 ＮＡ＝０．１
長１さ２９０ｍ
ボンピング光 １ 、０６４
ファイバ内パルスピークパワー５ＫＷ
ＹＡＧレーザ、モードロツタ１６０ＭＨｚ、Ｑ−スイッ
チｌ ｋＨｚ。sb-doped GeO2 core, diameter near 04m pure GeO2
Cladding, Diameter: 150gm Aperture ratio NA = 0.1 Length 1 Length 290m Bumping light 1,064 In-fiber pulse peak power 5KW YAG laser, mode rotator 160MHz, Q-switch l kHz.
この場合の分光特性は第４図に示す通りである（各スト
ークス光の半値幅は数７ｚｍである）。The spectral characteristics in this case are as shown in FIG. 4 (the half width of each Stokes beam is several 7 zm).
第５図にＯ印で示すものは伝搬遅延時間差の波長依存性
測定例である。What is indicated by O in FIG. 5 is an example of measuring the wavelength dependence of the propagation delay time difference.
τ （入）＝Ａ入４＋Ｂ入２＋Ｃ＋Ｄ入４ ＋ Ｅ −
４近似式を用い、この式に上記のデータを当てはめ、微
分（入に対して）によって零分散波長入〇（伝搬遅延時
間差が最大となる波長）及び分散値σが得られる。τ (in) = A input 4 + B input 2 + C + D input 4 + E −
Using the 4 approximation formula, and applying the above data to this formula, the zero dispersion wavelength (wavelength at which the propagation delay time difference is maximum) and the dispersion value σ are obtained by differentiation (with respect to input).
計算の結果
零分散波長入０＝１．３３１ルｍ
分散値ｃｒａｔ １ 、３０＝２．２１ｐｓ／ｎｍ／ｋ
ｍである。Calculation result Zero dispersion wavelength input 0 = 1.331 lm Dispersion value crat 1 , 30 = 2.21 ps/nm/k
It is m.
Ｓ ｉ ０２フアイバラマンレーザによる測定結果を同
時に第５図にＸ印で示す０両者は良く一致している。The measurement results using the S i 02 fiber Brahman laser are also shown as X marks in FIG. 5 and are in good agreement.
（発明の効果）
本発明は励起用光ファイバ２としてＧｅＯ２光ファイバ
を使用し、しかも同ファイバの分光特性が第４図に示す
通り各励起ストークス光のスペクトルが分離しており且
つシャープであり、１．１ルｍ〜１．７用ｍ波長域内に
ほぼ等間隔で分布しており、しかも各ストークス光の波
長シフトは約４２４ｃｍ’であるため、本発明によれば
次のような各種効果がある。(Effects of the Invention) The present invention uses a GeO2 optical fiber as the excitation optical fiber 2, and the spectral characteristics of the fiber are such that the spectra of each excitation Stokes light are separated and sharp, as shown in FIG. They are distributed at approximately equal intervals within the 1.1 m to 1.7 m wavelength range, and the wavelength shift of each Stokes beam is about 424 cm, so the present invention provides the following various effects. be.
（１）従来の測定系の分光器Ｃのかわりに簡易タイプの
回折格子或は光学的バンドフィルタ３を使用しても各ス
トークス光が十分に分離できる。(1) Even if a simple type diffraction grating or optical band filter 3 is used in place of the spectrometer C of the conventional measurement system, each Stokes beam can be sufficiently separated.
（２）分光器Ｃが不要となるためその分だけダイナミッ
クレンジが１ｏｄＢ以上改善され、高精度の測定が可能
になる。(2) Since the spectrometer C is not required, the dynamic range is improved by more than 1 odB, and highly accurate measurement becomes possible.
（３）ＳｉＯ２ファイバラマンレーザの分光特性と比べ
て、各ストークス光がシャープになる分だけ（ラマン散
乱断面積が大きいため）エネルギーが集中され、各スト
ークス光のパワーが大きくなる。(3) Compared to the spectral characteristics of the SiO2 fiber Raman laser, each Stokes beam becomes sharper (because the Raman scattering cross section is larger), and the energy is concentrated, and the power of each Stokes beam becomes larger.
（４）ダイナミックレンジが１ｏｄＢ以上改善さ１
′″ｈｉ＋ｘ“−“ｘ′（７）′＜ ７−”３°゛１
１尺な光ファイバの波長分散測定ができる。(4) Dynamic range improved by more than 1 odB1
′″hi+x″−“x′(7)′< 7−”3°゛1
It is possible to measure the chromatic dispersion of a one-meter optical fiber.
（５）測定系の構成が簡単になるため、計算、操作時間
などが短縮される。ちなみにＧｅＯ２ファイ八では７番
目のストークス光まで測定すれば１ 、１ ｐｍ〜１．
７４ｍ波長帯がカバーできるため測定点が７つで済むが
、５ｉ０２フアイバでは１．２ｐｍ−１，５ｐｍ波長帯
で、０．ＯＬｇｍ間隔で測定を行なう場合測定点が３１
ケとなり、Ｇｅｍ、ファイバの測定点数が５ｉ０２フア
イバの測定点の１／４となる。(5) Since the configuration of the measurement system is simplified, calculation and operation time are shortened. By the way, in GeO2 Phi 8, if you measure up to the 7th Stokes beam, it will be 1.1 pm to 1.1 pm.
Since it can cover the 74m wavelength band, only seven measurement points are required, but with the 5i02 fiber, it can cover the 1.2pm-1.5pm wavelength band, so it is 0. When measuring at OLgm intervals, there are 31 measurement points.
Therefore, the number of measurement points for Gem and fiber is 1/4 of the measurement points for 5i02 fiber.
また本発明では各ストークス光が分離し、しかもシャー
プであり、さらには各ストークス光に伝搬時間差がある
ため各ストークス光を被測定ファイバに同時に入力し、
データ処理することにより更に短時間に測定することが
できる。In addition, in the present invention, each Stokes beam is separated and sharp, and since each Stokes beam has a propagation time difference, each Stokes beam is simultaneously input into the fiber under test.
By processing the data, measurements can be made even more quickly.
（６）各ストークス光が１．ｌｐｍ〜１．７ｐｍにわた
って均一に分布しているため測定確度が容易に保たれる
。(6) Each Stokes light is 1. Since it is uniformly distributed over lpm to 1.7pm, measurement accuracy can be easily maintained.
第１図は本発明の測定系の一例を示す説明図、第２図は
５ｉ０２フアイバラマンレーザの分光特性の説明図、第
３図は従来の波長分散測定系の説明図、第４図はＧｅＯ
２ファイバラマンレーザの分光特性の説明図、第５図は
ＧｅＯ２ファイバラマンレーザと５ｉ０２フアイバラマ
ンレーザの伝搬遅延時間差の波長依存特性の説明図であ
る。
１は励起用光源
２は励起用光ファイバ
３はバンドフィルター
または簡易タイプの回折格子
４は被測定用光ファイバ
図面の浄′Ｓ（ｐ’１答に変更なし）
第 ２２
迎 ３ ：フ
第５図
１．ＯＬ＋ ＋２１．’３ Ｌ４
１５ １．６涙長Ｖグ）
手続補正書（方式）
％式％
ｌ 事件の表示 特願昭５９−１９２９３９号２
発明の名称 光ファイバの波長分散測定方法３
補正をする者
事件との関係 特許出願人
住所Fig. 1 is an explanatory diagram showing an example of the measurement system of the present invention, Fig. 2 is an explanatory diagram of the spectral characteristics of the 5i02 fiber Brahman laser, Fig. 3 is an explanatory diagram of the conventional wavelength dispersion measurement system, and Fig. 4 is an explanatory diagram of the GeO2 fiber Brahman laser.
FIG. 5 is an explanatory diagram of the spectral characteristics of the two-fiber Raman laser. FIG. 5 is an explanatory diagram of the wavelength-dependent characteristic of the propagation delay time difference between the GeO2 fiber Raman laser and the 5i02 fiber Raman laser. 1 is the excitation light source 2 is the excitation optical fiber 3 is a band filter or simple type diffraction grating 4 is the optical fiber to be measured. Figure 1. OL+ +21. '3 L4
15 1.6 tear length Vg) Procedural amendment (method) % formula % l Indication of case Patent application No. 192939/1989 2
Title of the invention Optical fiber chromatic dispersion measurement method 3
Relationship with the case of the person making the amendment Address of the patent applicant
Claims (1)
起用光ファイバに入射し、励起用光ファから発生される
誘導ラマン散乱光を用いて被測定用光ファイバの波長分
散を測定する方法において、励起用光ファイバとしてＧ
ｅＯ＿２光ファイバを使用するようにしたことを特徴と
する光ファイバの波長分散測定方法。In a method in which a laser from an excitation light source is incident on an excitation optical fiber that generates stimulated Raman scattering, and the chromatic dispersion of an optical fiber to be measured is measured using the stimulated Raman scattering light generated from the excitation optical fiber, G as a pumping optical fiber
A method for measuring chromatic dispersion of an optical fiber, characterized in that an eO_2 optical fiber is used.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP19293984A JPS6170437A (en) | 1984-09-14 | 1984-09-14 | Method for measuring wavelength dispersion of optical fiber |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP19293984A JPS6170437A (en) | 1984-09-14 | 1984-09-14 | Method for measuring wavelength dispersion of optical fiber |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS6170437A true JPS6170437A (en) | 1986-04-11 |
Family
ID=16299516
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP19293984A Pending JPS6170437A (en) | 1984-09-14 | 1984-09-14 | Method for measuring wavelength dispersion of optical fiber |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6170437A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100947731B1 (en) | 2008-01-30 | 2010-03-16 | 광주과학기술원 | Apparatus for and method of measuring chromatic dispersion of optical fiber and otical waveguide using spectral interferometer |
| KR100963237B1 (en) | 2008-01-18 | 2010-06-11 | 광주과학기술원 | Apparatus for calculating chromatic dispersion, and method therefor, and system for measuring chromatic dispersion, and method therefor, and the recording media storing the program performing the said methods |
-
1984
- 1984-09-14 JP JP19293984A patent/JPS6170437A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100963237B1 (en) | 2008-01-18 | 2010-06-11 | 광주과학기술원 | Apparatus for calculating chromatic dispersion, and method therefor, and system for measuring chromatic dispersion, and method therefor, and the recording media storing the program performing the said methods |
| KR100947731B1 (en) | 2008-01-30 | 2010-03-16 | 광주과학기술원 | Apparatus for and method of measuring chromatic dispersion of optical fiber and otical waveguide using spectral interferometer |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP7405175B2 (en) | Light source device for light measurement, spectrometer measurement device, and spectrometer measurement method | |
| JPH04276531A (en) | Optical-fiber type temperature-distribution measuring apparatus | |
| JPH0364812B2 (en) | ||
| CN107064100B (en) | Optical fiber Raman spectrometer based on dispersion time variation | |
| Luther-Davies et al. | Evaluation of material dispersion in low loss phosphosilicate core optical fibres | |
| US6462863B1 (en) | System and method for resolving polarization mode dispersion in optical fibers | |
| WO2020235441A1 (en) | Broadband pulsed light source, spectrometry device, and spectrometry method | |
| US10816720B2 (en) | Optical fiber with specialized figure-of-merit and applications therefor | |
| Hlubina | Experimental demonstration of the spectral interference between two beams of a low-coherence source at the output of a Michelson interferometer | |
| JPS6170437A (en) | Method for measuring wavelength dispersion of optical fiber | |
| Wiesenfeld et al. | Measurement of dispersion using short lengths of an optical fiber and picosecond pulses from semiconductor film lasers | |
| CN113008302B (en) | Temperature and acoustic resistance double-parameter sensing method and device based on forward Brillouin scattering | |
| US4068956A (en) | Pulsed laser densitometer system | |
| TW200530564A (en) | Wavelength meter | |
| Tanaka et al. | Scanless Brillouin gain spectrum measurement based on multi-heterodyne detection | |
| Ilev et al. | A fiber-optic autocollimation refractometric method for dispersion measurement of bulk optical materials using a widely tunable fiber Raman laser | |
| Smiley et al. | Material dispersion measurements on fiber optic cables used at the Nevada test site | |
| JPH075400Y2 (en) | Multi-channel curse measuring device | |
| JPH0231489A (en) | Soliton laser oscillation and apparatus | |
| JPS63309833A (en) | Zero-dispersion wavelength measuring method for optical fiber | |
| Lüpken et al. | Inline Measurement of Modal Phase Differences in Optical Fibers | |
| JPH10160633A (en) | Method for evaluating characteristic of single-mode optical fiber | |
| JPH0371050B2 (en) | ||
| Ackermann et al. | Femtosecond Two-Beam Coherent Anti-Stokes Raman Scattering for High Pressure Gas Analysis | |
| JPS6147534A (en) | Method and apparatus for measuring light loss characteristic of optical fiber |