WO1982002770A1 - Installation for the continuous testing of optical fibres - Google Patents
Installation for the continuous testing of optical fibres Download PDFInfo
- Publication number
- WO1982002770A1 WO1982002770A1 PCT/NL1982/000002 NL8200002W WO8202770A1 WO 1982002770 A1 WO1982002770 A1 WO 1982002770A1 NL 8200002 W NL8200002 W NL 8200002W WO 8202770 A1 WO8202770 A1 WO 8202770A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- fiber
- detector
- light
- light source
- installation
- 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.)
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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
- G01M11/35—Testing of optical devices, constituted by fibre optics or optical waveguides in which light is transversely coupled into or out of the fibre or waveguide, e.g. using integrating spheres
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/24—Coupling light guides
- G02B6/42—Coupling light guides with opto-electronic elements
- G02B6/4298—Coupling light guides with opto-electronic elements coupling with non-coherent light sources and/or radiation detectors, e.g. lamps, incandescent bulbs, scintillation chambers
Definitions
- the invention relates to a device for the continuous examination of optical fibers, in which light is coupled into the fiber from a light source and subsequently emerging scattered light is detected by means of a detector.
- Such devices are known, e.g. from the
- a similar direction is also known from DE-AS 24 51 654.
- a piece of the fiber to be examined is arranged there in a stationary manner and light is fed into the fiber.
- a movable measuring device now allows. To locate stray light spots on the fiber. However, a continuous measurement is not possible.
- the invention is therefore based on the object of improving a device of the type mentioned at the outset according to DE-AS 2744 219 in such a way that it is possible to examine for defects at the very beginning of the production process in order to be able to influence the process as early as possible.
- FIG. 1 shows the basic structure of the device
- FIG. 2 shows a first embodiment of the detector
- FIG. 3 shows a second embodiment of the detector
- FIG. 4 shows a third embodiment of the detector.
- a fore 1 of the later ep. Fiber is heated to about 2100 ° C in a drawing furnace 2 and drawn into a fiber 3. In drawing furnace 2, light is coupled into the fiber and passed on in the fiber. Are on the surface or inside the fiber
- the fiber After pulling the fiber, there is a log that provides information about where the faults are and how big they are. c.
- the fiber can be marked in color at the points at which faults were found, so that these points are quickly accessible for subsequent examination (cause of the fault).
- the drawing parameters for example the protective gas stream in the furnace, can be optimized so that a fiber with minimal disturbances is obtained.
- the store locations can also be found without color coding, since the positions are also included in the log.
- lens optics are used.
- the fiber 3 is introduced into a housing 14 through an inlet opening 13.
- a first lens 15 images a piece of the fiber onto a pinhole 16. This is imaged on a photocell 18 by a second lens 17.
- the light emerging from a defect 19 is converted into an electrical signal at the output 20.
- the fiber 3 leaves the housing 14 through an opening 21.
- FIG. 3 shows another embodiment of a detector, an Ulbricht sphere being used so that all directions of the scattered light can be detected.
- the fiber 3 enters an Ulbricht sphere 23, an ⁇ oto cell 18 converting stray light into an electrical signal.
- Shields 24 reduce interfering light from the environment.
- FIG. 4 shows a further detection possibility in which an internally mirrored rotational ellipsoid 26 is used in order to image scattered light from a scattering point 27 of the fiber 3 onto the photocell 18 and to convert it into an electrical signal.
- the protective tubes 28 serve to suppress stray light.
- a major advantage of the proposed device is that it allows the information obtained directly when the fiber is drawn to be used for process optimization. You do not have to wait until a fiber with defects is produced, but you can ensure good, error-free quality during production by appropriate process control. Another advantage is that no additional costly examination step is necessary is to get this quality information so that the entire production can be controlled and optimized. The fiber is measured without a coating and is not mechanically loaded.
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Investigating Materials By The Use Of Optical Means Adapted For Particular Applications (AREA)
- Investigating Or Analysing Materials By Optical Means (AREA)
- Surface Treatment Of Glass Fibres Or Filaments (AREA)
- Testing Of Optical Devices Or Fibers (AREA)
Abstract
Description
"Vorrichtung zur kontinuierlichen Untersuchung von Lichtleitfasrern" "Device for the continuous examination of optical fibers"
Die Erfindung bezieht sich auf eine Vorrichtung zur kontinuierlichen UntersuchungvonLichtleitfasern, wobei aus einer Lichtquelle Licht in die Faser eingekoppelt wird und wobei anschliessend austretendes Streulicht mittels eines Detektors erfasst wird. Derartige Vorrichtungen sind bekannt, so z.B. aus derThe invention relates to a device for the continuous examination of optical fibers, in which light is coupled into the fiber from a light source and subsequently emerging scattered light is detected by means of a detector. Such devices are known, e.g. from the
DE-AS 2744 219. Mit dieser bekannten Vorrichtung wird die bereits fertige, d.h. also auch schon mit einemLacküberzug versehene Faser auf Fehler untersucht.DE-AS 2744 219. With this known device the already finished, i.e. that is, fiber already coated with a varnish is examined for defects.
Eine ähnliche Vonrichtung ist auch aus der DE-AS 24 51 654 bekannt. Darin wird ein Stück der zu untersuchenden Faser ortsfest angeordnet und Licht wird in die Faser eingespeist. Eine bewegliche Messeinrichtung erlaubt nun. Streulichtstellen der Faser zu orten. Eine kontinuierliche Messung ist damit jedoch nicht möglich.A similar direction is also known from DE-AS 24 51 654. A piece of the fiber to be examined is arranged there in a stationary manner and light is fed into the fiber. A movable measuring device now allows. To locate stray light spots on the fiber. However, a continuous measurement is not possible.
Bei der Herstellung von Lichtleitfasern entstehen bei ungünstiger Wahl der Ziehparameter Defekte in der Oberfläche der Faser. Diese Defekte sind der bevorzugte Ausgangspunkt für Brüche der Faser unter schon geringen Zugbelastungen, wie sie bei der Verarbeitung und Benutzung auftreten können. Auch wenn die bestehende Zugbelastung nicht sofort zum Bruch führt, sind diese Stellen der Faseroberflache durch zugspannungsunterstützte Korrosion in der Altsrτingsbestandigkeit stark gemindert. Diese Oberflächendefekte sind möglichst zu venmeiden bzw. in der fertigen Faser zu finden. Durch Zerreisstests grosser Längen und Mengen von Fasern werden Festigkeitsstatistiken (Weibullveirteilungen) erstellt, um das Ziehverfahren zu optimieren. Dies ist ein aufwendiges und langwieriges Verfahren. In der Produktion werden die trotzdem vorhandenen Defekte in einem kontinuierlichen Zugbeansp-cuchungstest (Screentest, Prcoftest), dem die gesamte Faserproduktion unterworfen wird, auf eine bestimmte minimale Festigkeit hin geprüft. Danach hat man zwar die Information, dass diejenigen Fasern, die den Test bestanden haben, eine bestimmte Zugbear-spruchung ausgehalten. haben, jedoch hat man keinerlei Aussage darüber, wie die Festigkeit jenseits des Screentestwertes aussieht. Diesen Verfahren gegenüber bieten die eingangs genannten Vorrichtungen, die zerstörungsfreie Untersuchmgen erlauben, offensichtliche Vorteile. Hierbei werden Risse oder Ungleichmässigkeiten auf der Faseroberfläche mittels einer Streulichtmethode untersucht, nach welcher von dem Licht, das von einer Lichtquelle in die Lichtleitfaser zunächst eingestrahlt wird, das aus der Lichtleitfaser austretende Streulicht mittels einer Messeinrichtung gemessen wird.In the production of optical fibers, defects in the surface of the fiber arise if the drawing parameters are chosen unfavorably. These defects are the preferred starting point for fiber breaks under even low tensile loads, as can occur during processing and use. Even if the existing tensile load does not immediately lead to breakage, these areas of the fiber surface are greatly reduced in the old ring resistance due to tension-supported corrosion. These surface defects should be avoided as far as possible or found in the finished fiber. Strength tests (Weibull distributions) are created through tensile tests of large lengths and quantities of fibers in order to optimize the drawing process. This is a complex and lengthy process. In production, the defects that are still present are checked for a certain minimum strength in a continuous tensile stress test (screen test, prcoft test), to which the entire fiber production is subjected. After that, you have the information that the fibers that have passed the test can withstand a certain tensile stress. have, however, no statement about how the strength looks beyond the screen test value. The devices mentioned at the beginning, which allow non-destructive testing, offer these methods obvious advantages. In this case, cracks or irregularities on the fiber surface are examined by means of a scattered light method, according to which the light that is first radiated into the optical fiber from a light source is used to measure the scattered light emerging from the optical fiber by means of a measuring device.
Der Erfindung liegt somit die Aufgabe zugrunde, eine Vorrichtung der eingangs genannten Art nach der DE-AS 2744 219 dahingehend zu verbessern, dass eine Untersuchung auf Fehlerstellen bereits am Anfang des HersteHungsprozesses möglich ist, um den Prozess möglichst frühzeitig beeinflussen zu können.The invention is therefore based on the object of improving a device of the type mentioned at the outset according to DE-AS 2744 219 in such a way that it is possible to examine for defects at the very beginning of the production process in order to be able to influence the process as early as possible.
Die Losung dieser Aufgabe besteht darin, dass Ziehofen und Lichtquelle zu einer Einheit zusammengefasst sind und der Detektor unmittelbar anschliessend angeordnet ist.The solution to this problem is that drawing furnace and light source are combined into one unit and the detector is arranged immediately afterwards.
Dadurch ergibt sich der Vorteil, dass die Lichtleitfaser unmittelbar nach ihrer Herstellung auf Fehlerstellen untersucht werden kann. Anhand der Zeichnung wird ein Ausführungsbeispiel der Erfindung naher beschrieben. Darin zeigen:This has the advantage that the optical fiber can be examined for defects immediately after its manufacture. An embodiment of the invention is described in more detail with reference to the drawing. In it show:
Fig. 1 den prinzipiellen Aufbau der Vorrichtung, Fig. 2 eine erste Ausfuhrungsform des Detektors, Fig. 3 eine zweite Ausfuhrungsform des Detektors, und Fig. 4 eine dritte Ausführungsform des Detektors. Eine Vorfarm 1 der späterep. Faser wird in einem Ziehofen 2 auf etwa 2100ºC aufgeheizt und zu einer Faser 3 ausgezogen. Im ziehofen 2 wird Licht in die Faser eingekoppelt und in der Faser weitergeleitet. Befinden sich an der Oberfläche oder im Innern der Faser1 shows the basic structure of the device, FIG. 2 shows a first embodiment of the detector, FIG. 3 shows a second embodiment of the detector, and FIG. 4 shows a third embodiment of the detector. A fore 1 of the later ep. Fiber is heated to about 2100 ° C in a drawing furnace 2 and drawn into a fiber 3. In drawing furnace 2, light is coupled into the fiber and passed on in the fiber. Are on the surface or inside the fiber
Störungen, so streuen sie das Licht aus der Faser heraus. Dieses Streulicht wird in einem geeigneten Detektor 4 in ein elektrisches Signal umgewandelt und an eine Registrier- und Streuerelektronik 5 weitergeleitet. Danach wird die Faser 3 in einem Behälter 6 mit einem Lacküberzug versehen, der in einen Ofen 7 getrocknet und gehärtet wird. ImAnschluss daran hat die Strεuerelektronik 5 die Möglichkeit, mit Hilfe eines Faserrnarkiergerätes 8 z.B. eine Farrmarkierung auf der Faser 3 anzubringen. Danach gelangt die Faser auf eine Zieh- und Aufwickeltrotmmel 9, die von einem Wickelimotor mit Positionsgeber 10 angetrieben wird. Mit der Registrier- undStreuerelektronik lassen sich eine Reihe von Aufgaben realisieren, a. Während der Produktion einer Faser lassen sich die Streuamplitude und der Ort von Störungen registrieren. b. Nach dem Ziehen der Faser liegt ein Protokoll vor, das Auskunft darüber gibt, wo sich Störungen befinden und wie gross sie sind. c. Die Faser kann an den Stellen, an denen Störungen gefunden wurden, farblich markiert werden, so dass diese Stellen schnell für eine nachträgliche Untersuchung zugänglich sind (Störungsursache). d. Schon während des Ziehvorganges können die Ziehparameter, z.B. die Schutzgasstrαre im Ofen, so optimiert werden, dass man eine Faser mit minimalen Störungen erhält. e. Auch ohne farbliche Markierung sind die Storstellen zurückfindbar, da die Positionen auch im Protokoll enthalten sind.Faults, so they scatter the light out of the fiber. This scattered light is converted into an electrical signal in a suitable detector 4 and passed on to registration and scattering electronics 5. The fiber 3 is then provided with a lacquer coating in a container 6, which is dried and cured in an oven 7. Subsequently, the control electronics 5 have the option of using a fiber marking device 8, for example, to apply a fiber marking to the fiber 3. The fiber then arrives at a drawing and winding drum 9, which is driven by a winding motor with position transmitter 10. With the registration and spreader electronics, a number of tasks can be realized, a. During the production of a fiber, the scattering amplitude and the location of faults register. b. After pulling the fiber, there is a log that provides information about where the faults are and how big they are. c. The fiber can be marked in color at the points at which faults were found, so that these points are quickly accessible for subsequent examination (cause of the fault). d. Even during the drawing process, the drawing parameters, for example the protective gas stream in the furnace, can be optimized so that a fiber with minimal disturbances is obtained. e. The store locations can also be found without color coding, since the positions are also included in the log.
Einige Ausführungsforrnen des Detektors sind in den Figuren 2 bis 4 dargestellt.Some embodiments of the detector are shown in FIGS. 2 to 4.
Nach Fig. 2 wird eine Linsenoptik benutzt. Hierbei wird die Faser 3 durch eine Eingangsöffnung 13 in ein Gehäuse 14 eingeführt. Eine erste Linse 15 bildet ein Stück der Faser auf eine Lochblende 16 ab. Diese wird durch eine zweite Linse 17 auf eine Fotozelle 18 abgebildet. Das an einem Defekt 19 austretende Licht wird dabei in ein elektrisches Signal am Ausgang 20 gewandelt. Die Faser 3 verlässt das Gehäuse 14 durch eine Öffnung 21.2, lens optics are used. In this case, the fiber 3 is introduced into a housing 14 through an inlet opening 13. A first lens 15 images a piece of the fiber onto a pinhole 16. This is imaged on a photocell 18 by a second lens 17. The light emerging from a defect 19 is converted into an electrical signal at the output 20. The fiber 3 leaves the housing 14 through an opening 21.
In Fig. 3 ist eine andere Ausfuhrung eines Detektors dargestellt, wobei eine Ulbrichtsche Kugel zur Anwendung gelangt, so dass alle Richtungen des Streulichtes detektiert werden können. Die Faser 3 tritt in eine Ulbrichtsche Kugel 23 ein, wobei eine ϊotozelle 18 Streulicht in ein elektrisches Signal umwandelt. Abschirmungen 24 reduzieren störendes Licht aus der Umgebung.3 shows another embodiment of a detector, an Ulbricht sphere being used so that all directions of the scattered light can be detected. The fiber 3 enters an Ulbricht sphere 23, an ϊoto cell 18 converting stray light into an electrical signal. Shields 24 reduce interfering light from the environment.
In Fig. 4 ist eine weitere Detektionsmöglichkeit dargestellt, in der ein innenverspiegeltes Rotationsellipsoid 26 benutzt wird, um Streulicht einer Streustelle 27 der Faser 3 auf die Fotozelle 18 abzubilden und in ein elektrisches Signal zu wandeln. Auch hier dienen die Schutzröhrchen 28 zur Störlichtunterdrückung.4 shows a further detection possibility in which an internally mirrored rotational ellipsoid 26 is used in order to image scattered light from a scattering point 27 of the fiber 3 onto the photocell 18 and to convert it into an electrical signal. Here, too, the protective tubes 28 serve to suppress stray light.
Ein wesentlicher Vorteil der vorgeschlagenen Vorrichtung besteht darin, dass sie erlaubt, die direkt beim Ziehen der Faser gewonnenen Informationen zur Prozeessoptimierung zu nutzen. Man muss nicht erst warten, bis eine Faser mit Fehlern hergestellt ist, sondern man kann während der Herstellung für eine gute, fehlerfreie Qualität durch entsprechende Prozessführung sorgen. Ein weiterer Vorteil liegt darin, dass kein zusätzlicher kostenaufwendiger Untersuchungsschritt notwendig ist, um diese Qualitätsinformation zu erhalten, so dass die gesamte Produktion kontrolliert und optimiert werden kann. Die Faser wird ohne Überzug gemessen und mechanisch nicht belastet. A major advantage of the proposed device is that it allows the information obtained directly when the fiber is drawn to be used for process optimization. You do not have to wait until a fiber with defects is produced, but you can ensure good, error-free quality during production by appropriate process control. Another advantage is that no additional costly examination step is necessary is to get this quality information so that the entire production can be controlled and optimized. The fiber is measured without a coating and is not mechanically loaded.
Claims
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19813104076 DE3104076A1 (en) | 1981-02-06 | 1981-02-06 | "DEVICE FOR THE CONTINUOUS EXAMINATION OF LIGHT-CONDUCTING FIBERS" |
| DE3104076810206 | 1981-02-06 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| WO1982002770A1 true WO1982002770A1 (en) | 1982-08-19 |
Family
ID=6124172
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| PCT/NL1982/000002 Ceased WO1982002770A1 (en) | 1981-02-06 | 1982-02-03 | Installation for the continuous testing of optical fibres |
Country Status (4)
| Country | Link |
|---|---|
| EP (1) | EP0070853A1 (en) |
| JP (1) | JPS58500038A (en) |
| DE (1) | DE3104076A1 (en) |
| WO (1) | WO1982002770A1 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4678327A (en) * | 1984-12-24 | 1987-07-07 | Sumitomo Electric Industries, Ltd. | Method for inspecting an optical fiber |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE4022465A1 (en) * | 1990-07-14 | 1992-01-23 | Dornier Medizintechnik | LASER ENERGY MEASUREMENT AND CONTROL |
| AU742888B2 (en) * | 1997-05-22 | 2002-01-17 | Corning Incorporated | Methods and apparatus for detecting surface defects of an optical fiber |
| KR100516653B1 (en) * | 2002-07-29 | 2005-09-22 | 삼성전자주식회사 | Scattering monitor in optical fiber drawing system |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR1346674A (en) * | 1963-02-05 | 1963-12-20 | Corning Glass Works | Device and method for measuring radiant energy |
| US4081258A (en) * | 1976-05-12 | 1978-03-28 | International Telephone And Telegraph Corporation | Method for using on line optic fiber loss monitor |
| JPS5447672A (en) * | 1977-09-21 | 1979-04-14 | Nippon Telegr & Teleph Corp <Ntt> | Measuring method of transmission loss in optical transmission lines |
| GB1557154A (en) * | 1976-05-12 | 1979-12-05 | Int Standard Electric Corp | Optical attenuation measurement |
| JPS5569033A (en) * | 1978-11-20 | 1980-05-24 | Furukawa Electric Co Ltd:The | Measuring method of transmission loss of optical fiber |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2451654C3 (en) * | 1974-10-30 | 1984-08-09 | Siemens AG, 1000 Berlin und 8000 München | Device for measuring imperfections and / or lengths of glass fibers |
| DE2744219C3 (en) * | 1977-09-30 | 1980-08-28 | Siemens Ag, 1000 Berlin Und 8000 Muenchen | Device for the non-destructive examination of optical fibers |
-
1981
- 1981-02-06 DE DE19813104076 patent/DE3104076A1/en active Granted
-
1982
- 1982-02-03 WO PCT/NL1982/000002 patent/WO1982002770A1/en not_active Ceased
- 1982-02-03 EP EP19820900389 patent/EP0070853A1/en not_active Withdrawn
- 1982-02-03 JP JP57500560A patent/JPS58500038A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR1346674A (en) * | 1963-02-05 | 1963-12-20 | Corning Glass Works | Device and method for measuring radiant energy |
| US4081258A (en) * | 1976-05-12 | 1978-03-28 | International Telephone And Telegraph Corporation | Method for using on line optic fiber loss monitor |
| GB1557154A (en) * | 1976-05-12 | 1979-12-05 | Int Standard Electric Corp | Optical attenuation measurement |
| JPS5447672A (en) * | 1977-09-21 | 1979-04-14 | Nippon Telegr & Teleph Corp <Ntt> | Measuring method of transmission loss in optical transmission lines |
| JPS5569033A (en) * | 1978-11-20 | 1980-05-24 | Furukawa Electric Co Ltd:The | Measuring method of transmission loss of optical fiber |
Non-Patent Citations (4)
| Title |
|---|
| Applied Optics, Vol. 13, No. 8, published in August 1974, New-York (US) F. OSTERMAYER u.a.: "Integrating Sphere for Measuring Scattering loss in Optical Fiber Waveguides", pages 1900-1902, see the whole document * |
| PATENTS ABSTRACTS OF JAPAN, Vol. 3, No. 10, page 38E117, published on 16 June 1979, & JP, A, 54047672 (Nippon Denshin Denwa Kosha) 14.04.1979 see the whole document * |
| PATENTS ABSTRACTS OF JAPAN, Vol. 4, No. 10, page 157P22, published on 8 August 1980, & JP, A, 55069033, (Furukawa Denki Kogyo K.K.) 24.05.1980, see the whole document * |
| Soviet Physics - Technical Physics, Vol. 25, No. 6, published in June 1980, New York (US) I. ALEKSANDROV u.a.: "An Automatic System for Measuring Optical Fiber Parameters During Drawing", pages 739-743, see pages 740-741 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4678327A (en) * | 1984-12-24 | 1987-07-07 | Sumitomo Electric Industries, Ltd. | Method for inspecting an optical fiber |
Also Published As
| Publication number | Publication date |
|---|---|
| EP0070853A1 (en) | 1983-02-09 |
| DE3104076A1 (en) | 1982-10-21 |
| JPS58500038A (en) | 1983-01-06 |
| DE3104076C2 (en) | 1989-02-16 |
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