CN112198591B - Fresnel noise suppression unit at tail end of optical fiber and manufacturing method thereof - Google Patents
Fresnel noise suppression unit at tail end of optical fiber and manufacturing method thereof Download PDFInfo
- Publication number
- CN112198591B CN112198591B CN202011052599.5A CN202011052599A CN112198591B CN 112198591 B CN112198591 B CN 112198591B CN 202011052599 A CN202011052599 A CN 202011052599A CN 112198591 B CN112198591 B CN 112198591B
- Authority
- CN
- China
- Prior art keywords
- optical fiber
- fiber
- noise suppression
- fresnel
- tail
- 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.)
- Active
Links
Images
Classifications
-
- 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
- G02B6/26—Optical coupling means
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Optical Couplings Of Light Guides (AREA)
Abstract
The invention provides an optical fiber tail end Fresnel noise suppression unit and a manufacturing method thereof, wherein an optical fiber assembly comprises an optical fiber tail end unit, the optical fiber tail end unit comprises a signal transmission section and a noise suppression section, the signal transmission section comprises a sensing optical fiber, and the sensing optical fiber is used for transmitting acoustic wave optical signals after Fresnel noise suppression; the noise suppression section is connected with the signal transmission section, and the noise suppression section includes the tail optical fiber, and the tail optical fiber is connected with sensing optical fiber signal, and the tail optical fiber has the annular circle structure, and the annular circle structure is used for introducing optical fiber transmission loss to carry out preliminary suppression to the produced noise of the terminal fresnel effect of optical fiber. The invention solves the problems of low signal-to-noise ratio and poor data interpretation precision of monitoring signals of the optical fiber component in the prior art during optical fiber sound wave testing.
Description
Technical Field
The invention relates to the technical field of underground optical fiber sound wave testing of oil and gas fields, in particular to an optical fiber tail end Fresnel noise suppression unit and a manufacturing method thereof.
Background
In the prior art, the method has the defects that,
the ODTR phase-sensitive optical time domain reflectometer realizes long-distance sensing of disturbance signals such as strain, vibration and the like through the change of back Rayleigh scattering light signals generated in the transmission process of light, and is used in
in-ODTR phase sensitive optical time domain reflectometer process, it is strongerThe fresnel noise reflection easily covers the effective optical signal near the end of the optical fiber, resulting in a low signal-to-noise ratio of the monitoring signal, and the accuracy and interpretation effect of the acoustic wave monitoring signal cannot be guaranteed.
The existing optical fiber assembly inhibits the reflection of Fresnel noise by arranging an isolator at the tail end of an optical fiber, and the optical fiber assembly is mainly suitable for the field of telecommunication, and cannot be suitable for a limited space under an oil and gas field due to the large size of the isolator; or, the existing optical fiber assembly absorbs the reflected light signal by installing the reflected light suppression unit to achieve the purpose of reducing the reflectivity, thereby improving the signal-to-noise ratio of the monitoring signal, but the optical fiber assembly with the reflected light suppression unit increases the loss of the optical path, which is not beneficial to the energy saving of the light source of the optical fiber assembly.
Disclosure of Invention
The invention mainly aims to provide an optical fiber end Fresnel noise suppression unit and a manufacturing method thereof, and aims to solve the problems that in the prior art, the signal-to-noise ratio of a monitoring signal of the optical fiber end Fresnel noise suppression unit is low and the data interpretation precision is poor during optical fiber sound wave testing.
In order to achieve the above object, according to one aspect of the present invention, there is provided an optical fiber end fresnel noise suppression unit, including an optical fiber end unit, the optical fiber end unit including a signal transmission section and a noise suppression section, wherein the signal transmission section includes a sensing optical fiber, and the sensing optical fiber is used for transmitting acoustic wave optical signals after fresnel noise suppression; the noise suppression section is connected with the signal transmission section, and the noise suppression section includes the tail optical fiber, and the tail optical fiber is connected with sensing optical fiber signal, and the tail optical fiber has the annular circle structure, and the annular circle structure is used for introducing optical fiber transmission loss to carry out preliminary suppression to the produced noise of the terminal fresnel effect of optical fiber.
Further, a part of the pigtail is coiled around an axis parallel to the length direction of the pigtail to form an annular loop structure.
Further, an annular ring structure is located between the two ends of the pigtail.
Further, the curvature radius of the annular ring structure is R, wherein R is more than 0 and less than 8mm.
Furthermore, the number of turns of the annular ring structure is A, wherein A is more than or equal to 2 turns and less than or equal to 5 turns.
Further, the tail fiber and the sensing fiber are arranged with an included angle.
Furthermore, the signal transmission section also comprises a first cladding, the first cladding is coated on the outer peripheral side of the sensing optical fiber, and the sensing optical fiber and the first cladding are coaxially arranged; the noise suppression section further comprises a second cladding, the second cladding is coated on the outer peripheral side of the tail fiber, one end, far away from the annular ring structure, of the tail fiber is half-coated, so that one end, used for being connected with the sensing optical fiber, of the tail fiber is exposed, and the end portion of the signal transmission section and the end portion of the noise suppression section are arranged in a staggered mode.
Further, the fiber end unit includes a protection structure disposed at a connection position of the sensing fiber and the pigtail and filling a gap between the signal transmission section and the noise suppression section.
Furthermore, the optical fiber tail end Fresnel noise suppression unit further comprises a surface layer protection structure, the surface layer protection structure is provided with an accommodating cavity, the accommodating cavity is used for accommodating the optical fiber tail end unit, and the outer peripheral side of the optical fiber tail end unit and the cavity wall surface of the accommodating cavity are bonded and fixed in a dispensing mode.
Furthermore, the surface layer protection structure comprises a guide plug, and the guide plug is arranged at the end part, close to the noise suppression section, of the surface layer protection structure.
According to another aspect of the present invention, a manufacturing method of a fresnel noise suppression unit at an end of an optical fiber is provided, the manufacturing method is used for manufacturing the fresnel noise suppression unit at the end of the optical fiber, and the manufacturing method includes the following steps: s1, looping and knotting the tail fiber of a noise suppression section to enable the tail fiber to have an annular ring structure; and S2, connecting the signal transmission section with the noise suppression section, and connecting the sensing optical fiber of the signal transmission section with the tail fiber of the noise suppression section, wherein the tail fiber has an annular ring structure.
Further, in step S1, the looping and knotting processing method includes coiling a part of the pigtail around an axis parallel to a length direction of the pigtail to form an annular loop structure.
Further, after the step S1 and before the step S2, a step S10 is further included, in which a second cladding is coated on an outer peripheral side of the pigtail, and an end of the pigtail, which is far away from the annular ring structure, is half-coated, so that an end of the pigtail, which is used for being connected with the sensing optical fiber, is exposed.
Further, in step S2, the sensing fiber and the pigtail are fusion-spliced so that the sensing fiber and the pigtail are arranged with an included angle, and a protection structure is arranged at a connection position of the sensing fiber and the pigtail.
Further, step S3 is included after step S2, the optical fiber end unit is placed in the accommodating cavity of the surface layer protection structure, and the optical fiber end unit and the surface layer protection structure are fixed in an adhesive manner by dispensing.
By applying the technical scheme of the invention, the tail fiber of the noise suppression section of the optical fiber tail end unit is set to be in a structural form with the annular ring structure, so that the tail fiber has an uneven end surface due to the existence of the annular ring structure, namely, the annular ring structure plays a role in introducing bending loss so as to achieve the purpose of primary noise reduction.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:
FIG. 1 is a flow chart illustrating a method for fabricating an end-of-fiber Fresnel noise suppression unit according to an alternative embodiment of the present invention;
FIG. 2 is a schematic diagram illustrating a partial structure of a fiber-end Fresnel noise suppression unit according to an alternative embodiment of the present invention;
fig. 3 is a schematic diagram showing a partial structure of the fiber end unit of the fiber end fresnel noise suppressing unit in fig. 2;
FIG. 4 shows a schematic partial structure of the noise suppression section of the fiber termination unit of FIG. 3;
FIG. 5 shows a test curve of the end of the fiber end Fresnel noise suppression unit before noise suppression;
fig. 6 shows a test curve after noise suppression of the end of the fiber end fresnel noise suppression unit.
Wherein the figures include the following reference numerals:
1. an optical fiber end unit; 10. a signal transmission section; 11. a sensing optical fiber; 12. a first cladding layer; 20. a noise suppression section; 21. tail fiber; 211. an annular ring structure; 22. a second cladding layer; 30. a protective structure; 2. a surface layer protection structure; 40. an accommodating chamber; 50. and (6) guiding the plug.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The invention provides an optical fiber tail end Fresnel noise suppression unit and a manufacturing method thereof, and aims to solve the problems that the signal-to-noise ratio of a monitoring signal of an optical fiber assembly in the optical fiber sound wave test is low and the data interpretation precision is poor in the prior art.
As shown in fig. 1, the method for manufacturing the fresnel noise suppression unit at the end of the optical fiber is used for manufacturing the fresnel noise suppression unit at the end of the optical fiber and the following steps:
step S1, performing looping and knotting processing on the tail fiber 21 of the noise suppression section 20 to enable the tail fiber 21 to have an annular loop structure 211;
and S2, connecting the signal transmission section 10 with the noise suppression section 20, and connecting the sensing optical fiber 11 of the signal transmission section 10 with the tail optical fiber 21 with the annular ring structure 211 of the noise suppression section 20.
It should be noted that, in step S1, the looping processing method includes coiling a part of the pigtail 21 around an axis parallel to the length direction of the pigtail 21 to form the annular loop structure 211.
It should be noted that, after step S1 and before step S2, step S10 is further included, the second cladding 22 is coated on the outer peripheral side of the pigtail 21, and one end of the pigtail 21 away from the annular ring structure 211 is half-coated, so that one end of the pigtail 21 for connecting with the sensing optical fiber 11 is exposed.
In step S2, the sensing fiber 11 and the pigtail 21 are fusion-spliced so that the sensing fiber 11 and the pigtail 21 are arranged at an angle, and the protection structure 30 is provided at the connection position of the sensing fiber 11 and the pigtail 21.
It should be noted that, after step S2, step S3 is further included, the optical fiber end unit 1 is placed in the accommodating cavity 40 of the surface layer protection structure 2, and the optical fiber end unit 1 and the surface layer protection structure 2 are adhesively fixed by means of dispensing.
As shown in fig. 2 and fig. 3, the optical fiber end fresnel noise suppression unit includes an optical fiber end unit 1, and the optical fiber end unit 1 includes a signal transmission section 10 and a noise suppression section 20, where the signal transmission section 10 includes a sensing optical fiber 11, and the sensing optical fiber 11 is used for transmitting the acoustic wave optical signal after fresnel noise suppression; the noise suppression section 20 is connected with the signal transmission section 10, the tail fiber 21 is in signal connection with the sensing fiber 11, the noise suppression section 20 comprises the tail fiber 21, the tail fiber 21 is provided with an annular ring structure 211, and the annular ring structure 211 is used for introducing fiber transmission loss so as to perform primary suppression on noise generated by the Fresnel effect at the tail end of the fiber.
Set tail optical fiber 21 through the noise suppression section 20 with the terminal unit 1 of optic fibre to the structural style that has annular ring structure 211, thus, because the existence of annular ring structure 211 makes tail optical fiber 21 have uneven terminal surface, namely, annular ring structure 211 has played the effect of introducing bending loss, in order to reach the purpose of making an uproar preliminarily, when the terminal fei nieer noise suppression unit of optic fibre carries out the optic fibre sound wave test, avoid the terminal strong noise of the terminal fei nieer noise suppression unit of optic fibre to cover effective light signal, be favorable to promoting monitoring signal's SNR, and then ensure the precision and the explanation effect of sound wave monitoring signal.
As shown in fig. 2 to 4, part of the pigtail 21 is coiled around an axis parallel to the length direction of the pigtail 21 to form an annular loop structure 211. Thus, on the premise of ensuring that the tail fiber 21 has a non-flat interface, the ring-shaped structure 211 is formed by coiling in a looping mode, and the operation is convenient and fast.
It should be noted that, in the present application, in order to ensure the connection reliability of the pigtail 21 and the sensing optical fiber 11, the annular ring structure 211 is located between two ends of the pigtail 21. In this way, interference with the connection of pigtail 21 to sensing fiber 11 due to the presence of annular ring structure 211 is avoided.
It should be noted that, in the present application, the radius of curvature of the annular ring structure 211 is R, wherein 0 < R < 8mm. In this way, by optimizing the radius of curvature of the annular ring structure 211 to R, it is ensured that the fiber loss is introduced while breakage can be avoided at the position of the pigtail 21 having the annular ring structure 211.
It should be noted that, in the present application, the number of turns of the annular ring structure 211 is a, where a is greater than or equal to 2 turns and less than or equal to 5 turns. Thus, the loss of the optical fiber is further improved by optimizing the number of turns of the annular ring structure 211 to be A, and meanwhile, the breakage of the tail fiber 21 at the position with the annular ring structure 211 is avoided.
It should be noted that, in the present application, the pigtail 21 is disposed at an angle to the sensing fiber 11. Therefore, the tail fiber 21 and the sensing optical fiber 11 are subjected to dislocation fiber melting to achieve the purpose of changing the refractive index of incident light, the reflection intensity coefficient of Fresnel noise is further reduced by the arrangement of the dislocation angle, the purpose of finally inhibiting the Fresnel noise at the tail end of the optical fiber is achieved, and when the Fresnel noise inhibiting unit at the tail end of the optical fiber performs optical fiber sound wave test, the tail end strong noise coverage is prevented from being effective.
As shown in fig. 2 and 3, the pigtail 21 and the sensing fiber 11 have an angle C, which is 35 °.
As shown in fig. 2 and 3, the signal transmission section 10 further includes a first cladding 12, the first cladding 12 is coated on the outer peripheral side of the sensing fiber 11, and the sensing fiber 11 and the first cladding 12 are coaxially disposed; the noise suppression section 20 further includes a second cladding 22, the second cladding 22 is coated on the outer peripheral side of the pigtail 21, and one end of the pigtail 21 away from the annular ring structure 211 is half-coated, so that one end of the pigtail 21 used for being connected with the sensing optical fiber 11 is exposed, and the end of the signal transmission section 10 and the end of the noise suppression section 20 are arranged in a staggered manner. Thus, the first cladding 12 functions to protect the sensing fiber 11, while the second cladding 22 functions to protect the pigtail 21; in addition, the end of the pigtail 21 far away from the annular ring structure 211 is half-coated, so that the subsequent normal fiber melting operation of the pigtail 21 and the sensing optical fiber 11 is facilitated.
Optionally, both the first cladding 12 and the second cladding 22 are made of nylon material, injection molded into a cable.
As shown in fig. 2 and 3, the optical fiber termination unit 1 includes a protection structure 30, and the protection structure 30 is disposed at a connection position of the sensing optical fiber 11 and the pigtail 21 and fills a gap between the signal transmission section 10 and the noise suppression section 20. In this way, the protective structure 30 serves to protect the connection position of the sensing fiber 11 and the pigtail 21, and fills the gap between the connection signal transmission section 10 and the noise suppression section 20, thereby ensuring the integrity of the fiber end unit 1 and also serving as a seal.
It should be noted that, in the present application, the protection structure 30 is a flexible tube made of polyimide, and can be applied to a high temperature and corrosive environment in an oil and gas well, so that the fresnel noise suppression unit at the end of the optical fiber avoids a fracture phenomenon at the connection position of the signal transmission section 10 and the noise suppression section 20 during the operation process in the well.
In the present application, in order to protect the entire optical fiber termination unit 1, as shown in fig. 2, the optical fiber termination fresnel noise suppression unit further includes a surface layer protection structure 2, the surface layer protection structure 2 has an accommodation cavity 40, the accommodation cavity 40 is used to accommodate the optical fiber termination unit 1, and the outer peripheral side of the optical fiber termination unit 1 and the cavity wall surface of the accommodation cavity 40 are adhesively fixed by means of glue.
Optionally, the surface protection structure 2 is a 316L stainless steel pipe, and has the advantages of corrosion resistance, large curvature radius, high external extrusion resistance, and the like.
Note that, in the present application, in order to ensure that the fiber-end fresnel noise suppression unit can be smoothly transported downhole, as shown in fig. 2, the surface layer protection structure 2 includes a guide plug 50, and the guide plug 50 is disposed at an end of the surface layer protection structure 2 close to the noise suppression section 20.
Optionally, the guiding plug 50 is an oval guiding plug, so that the fresnel noise suppression unit at the end of the subsequent optical fiber can enter the well smoothly.
It should be noted that, in the present application, the sensing optical fiber 11 and the pigtail 21 both adopt single mode optical fibers, and the fiber cores and the coating layers are made of the same material, which facilitates fiber melting, reduces the attenuation degree of the spliced optical fiber, and ensures the transmission quality of optical link signals.
As shown in fig. 5, the test curve has fresnel reflection peaks in the range of 0 to 0.3km, and the fresnel reflection peaks in the sections a to B on the horizontal axis are dense and distinct.
As shown in fig. 6, in the range of 0 to 0.3km, the fresnel reflection peak in the test curve disappears, and the fresnel reflection peaks in the sections a to B on the horizontal axis are more sparse.
It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.
The relative arrangement of the components and steps, the numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless specifically stated otherwise. Meanwhile, it should be understood that the sizes of the respective portions shown in the drawings are not drawn in an actual proportional relationship for the convenience of description. Techniques, methods, and apparatus known to one of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate. In all examples shown and discussed herein, any particular value should be construed as exemplary only and not as limiting. Thus, other examples of the exemplary embodiments may have different values. It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be discussed further in subsequent figures.
For ease of description, spatially relative terms such as "over … …", "over … …", "over … …", "over", etc. may be used herein to describe the spatial positional relationship of one device or feature to another device or feature as shown in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if a device in the figures is turned over, devices described as "above" or "on" other devices or configurations would then be oriented "below" or "under" the other devices or configurations. Thus, the exemplary term "above … …" may include both orientations of "above … …" and "below … …". The device may be otherwise variously oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.
It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular is intended to include the plural unless the context clearly dictates otherwise, and it should be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of features, steps, operations, devices, components, and/or combinations thereof.
It should be noted that the terms "first," "second," and the like in the description and claims of this application and in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the application described herein are capable of operation in sequences other than those illustrated or described herein.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (14)
1. An end-of-fiber fresnel noise suppression unit, comprising an end-of-fiber unit (1), the end-of-fiber unit (1) comprising:
the signal transmission section (10), the signal transmission section (10) comprises a sensing optical fiber (11), and the sensing optical fiber (11) is used for transmitting the acoustic wave optical signal subjected to Fresnel noise suppression;
a noise suppression section (20), wherein the noise suppression section (20) is connected with the signal transmission section (10), the noise suppression section (20) comprises a tail fiber (21), the tail fiber (21) is in signal connection with the sensing optical fiber (11), the tail fiber (21) is provided with an annular ring structure (211), and the annular ring structure (211) is used for introducing optical fiber transmission loss so as to perform primary suppression on noise generated by the Fresnel effect at the end of the optical fiber;
a protective structure (30), the protective structure (30) being arranged at a connection location of the sensing fiber (11) and the pigtail (21) and filling a gap between the signal transmission section (10) and the noise suppression section (20).
2. The fiber end fresnel noise suppression unit according to claim 1, wherein a portion of the pigtail (21) is coiled around an axis parallel to a length direction of the pigtail (21) to form the annular loop structure (211).
3. The fiber end fresnel noise suppression unit according to claim 2, characterized in that the annular ring structure (211) is located between two ends of the pigtail (21).
4. The fiber end fresnel noise suppression unit according to claim 3, characterized in that the radius of curvature of the annular ring structure (211) is R, wherein 0 < R < 8mm.
5. The fiber end Fresnel noise suppression unit according to claim 4, characterized in that the number of turns of the annular ring structure (211) is A, wherein A is more than or equal to 2 and less than or equal to 5 turns.
6. The fiber end fresnel noise suppression unit according to claim 5, characterized in that the pigtail (21) is arranged at an angle to the sensing fiber (11).
7. The fiber end Fresnel noise suppression unit according to claim 6,
the signal transmission section (10) further comprises:
a first cladding (12), wherein the first cladding (12) is coated on the outer periphery side of the sensing optical fiber (11), and the sensing optical fiber (11) and the first cladding (12) are coaxially arranged;
the noise suppression section (20) further comprises:
the second cladding layer (22) is coated on the outer peripheral side of the tail fiber (21), one end, far away from the annular ring structure (211), of the tail fiber (21) is semi-coated, so that one end, used for being connected with the sensing optical fiber (11), of the tail fiber (21) is exposed, and the end portion of the signal transmission section (10) and the end portion of the noise suppression section (20) are arranged in a staggered mode.
8. The fiber-end fresnel noise suppression unit according to claim 1, further comprising:
the surface layer protection structure (2), the surface layer protection structure (2) has and holds chamber (40), hold chamber (40) and be used for holding fiber end unit (1), the periphery side of fiber end unit (1) with hold between the chamber wall face of chamber (40) and glue the mode and bond fixedly.
9. The fiber tip fresnel noise suppression unit according to claim 8, characterized in that the surface protection structure (2) comprises a guide plug (50), the guide plug (50) being arranged at an end of the surface protection structure (2) close to the noise suppression section (20).
10. A method for manufacturing a fresnel noise suppression unit at an end of an optical fiber, the method being used for manufacturing the fresnel noise suppression unit at an end of an optical fiber according to any one of claims 1 to 9, and the method comprising the steps of:
step S1, performing looping and knotting processing on a tail fiber (21) of a noise suppression section (20) to enable the tail fiber (21) to have an annular ring structure (211);
and S2, connecting the signal transmission section (10) with the noise suppression section (20), and connecting the sensing optical fiber (11) of the signal transmission section (10) with a tail fiber (21) with an annular ring structure (211) of the noise suppression section (20).
11. The method for manufacturing the fiber end fresnel noise suppression unit according to claim 10, wherein in the step S1, the looping processing method includes coiling a part of the tail fiber (21) around an axis parallel to a length direction of the tail fiber (21) to form an annular loop structure (211).
12. The method for manufacturing a fiber-end fresnel noise suppression unit according to claim 11, further comprising, after the step S1 and before the step S2:
and S10, coating a second coating (22) on the peripheral side of the tail fiber (21), wherein one end, away from the annular ring structure (211), of the tail fiber (21) is semi-coated, so that one end, used for being connected with the sensing optical fiber (11), of the tail fiber (21) is exposed.
13. The method for manufacturing the optical fiber end fresnel noise suppression unit according to claim 12, wherein in the step S2, the sensing optical fiber (11) and the pigtail (21) are fused to each other, so that the sensing optical fiber (11) and the pigtail (21) are arranged at an included angle, and a protection structure (30) is arranged at a connection position of the sensing optical fiber (11) and the pigtail (21).
14. The method for manufacturing a fresnel noise suppression unit according to claim 13, wherein the fresnel noise suppression unit is formed at the end of the optical fiber
Step S2 is followed by:
and S3, placing the optical fiber tail end unit (1) in an accommodating cavity (40) of the surface layer protection structure (2), and adhering and fixing the optical fiber tail end unit (1) and the surface layer protection structure (2) in a dispensing manner.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011052599.5A CN112198591B (en) | 2020-09-29 | 2020-09-29 | Fresnel noise suppression unit at tail end of optical fiber and manufacturing method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011052599.5A CN112198591B (en) | 2020-09-29 | 2020-09-29 | Fresnel noise suppression unit at tail end of optical fiber and manufacturing method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112198591A CN112198591A (en) | 2021-01-08 |
| CN112198591B true CN112198591B (en) | 2023-02-28 |
Family
ID=74008037
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011052599.5A Active CN112198591B (en) | 2020-09-29 | 2020-09-29 | Fresnel noise suppression unit at tail end of optical fiber and manufacturing method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112198591B (en) |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5581649A (en) * | 1995-04-28 | 1996-12-03 | The Whitaker Corporation | Fixed value fiber optic attenuator with index matching material |
| CN101581586B (en) * | 2009-06-23 | 2010-11-10 | 中国科学院安徽光学精密机械研究所 | Distributed optical fiber sagnac positioning sensor inhibiting dead zone of sensor |
| CN104535819B (en) * | 2015-01-09 | 2018-06-01 | 胡雨亭 | The polarization error restraining device and method of the Y waveguide loop of optical fiber current mutual inductor |
| CN106556415A (en) * | 2015-09-28 | 2017-04-05 | 中兴通讯股份有限公司 | Laser phase noise elimination apparatus, system and method |
| CN106323339A (en) * | 2016-08-23 | 2017-01-11 | 中国航空工业集团公司西安飞行自动控制研究所 | Manufacturing method for low intensity and tiny noise closed-loop fiber-optic gyroscope |
| CN106646754A (en) * | 2016-11-29 | 2017-05-10 | 北京天海蓝业科技有限公司 | Device and method for eliminating end reflected light noise of fiber and optical cable |
| CN111189592A (en) * | 2019-11-08 | 2020-05-22 | 江苏法尔胜光电科技有限公司 | Distributed optical fiber detection system for leakage of acidic medium conveying pipeline and detection method thereof |
-
2020
- 2020-09-29 CN CN202011052599.5A patent/CN112198591B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN112198591A (en) | 2021-01-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US7389031B2 (en) | Reflection suppression for an optical fiber | |
| US5764840A (en) | Optical fiber with enhanced light collection and illumination and having highly controlled emission and acceptance patterns | |
| US8050527B2 (en) | Self healing optical fiber cable assembly and method of making the same | |
| US5130535A (en) | Methods of and apparatus for measuring bending loss along a length of optical fiber | |
| CN201017071Y (en) | Flexible metal sleeve optical fiber jumper wire | |
| CA2489858C (en) | Splice for optical cable | |
| AU2012217824A1 (en) | Fiber optic cable with electrical conductors | |
| CN112198591B (en) | Fresnel noise suppression unit at tail end of optical fiber and manufacturing method thereof | |
| CN114088241A (en) | Weak fiber grating array temperature/vibration composite sensing optical cable and use method thereof | |
| CN110780410A (en) | Sensitivity-enhanced soft light distributed acoustic wave sensing optical cable | |
| US5492281A (en) | Base layer of coated glass fiber for a bobbin | |
| JP2784155B2 (en) | Optical fiber high speed feeding test equipment | |
| JP2000089042A (en) | Optical fiber sensor and detection of information using the same | |
| CA2663767A1 (en) | Ferrule for an evanescence field sensor line | |
| JPH04148836A (en) | Liquid-leakage detecting apparatus | |
| CN109814216A (en) | A kind of fibre optic hydrophone tail optical fiber deriving structure | |
| Sumida et al. | Fundamental studies on flat bunched optical fibers | |
| CN211206870U (en) | Grating reflector convenient to retrieve | |
| CN219870226U (en) | Optical fiber macrobend loss testing device | |
| JPS6343111A (en) | Optical fiber branching device | |
| CN214311013U (en) | Submarine armored optical cable tail end strength eliminating device with optical fiber redundancy device | |
| CN110686867B (en) | Optical return loss calibration transfer device and method | |
| CN209978812U (en) | Carbon coated optical fiber interferometer for deep water application | |
| JP2000205999A (en) | Optical fiber measuring apparatus | |
| JPS60211334A (en) | Nondisconnection detecting device for optical fiber |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |