CN108768526B - Bidirectional fiber grating manufacturing method, bidirectional tracker and passive network - Google Patents
Bidirectional fiber grating manufacturing method, bidirectional tracker and passive network Download PDFInfo
- Publication number
- CN108768526B CN108768526B CN201810778188.0A CN201810778188A CN108768526B CN 108768526 B CN108768526 B CN 108768526B CN 201810778188 A CN201810778188 A CN 201810778188A CN 108768526 B CN108768526 B CN 108768526B
- Authority
- CN
- China
- Prior art keywords
- grating
- optical fiber
- chirped
- chirped grating
- fiber
- 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
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
- H04B10/25—Arrangements specific to fibre transmission
- H04B10/2589—Bidirectional transmission
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B5/00—Optical elements other than lenses
- G02B5/18—Diffraction gratings
- G02B5/1847—Manufacturing methods
- G02B5/1857—Manufacturing methods using exposure or etching means, e.g. holography, photolithography, exposure to electron or ion beams
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
- H04B10/07—Arrangements for monitoring or testing transmission systems; Arrangements for fault measurement of transmission systems
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04Q—SELECTING
- H04Q11/00—Selecting arrangements for multiplex systems
- H04Q11/0001—Selecting arrangements for multiplex systems using optical switching
- H04Q11/0062—Network aspects
- H04Q11/0067—Provisions for optical access or distribution networks, e.g. Gigabit Ethernet Passive Optical Network (GE-PON), ATM-based Passive Optical Network (A-PON), PON-Ring
Landscapes
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Electromagnetism (AREA)
- Signal Processing (AREA)
- Manufacturing & Machinery (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Optical Fibers, Optical Fiber Cores, And Optical Fiber Bundles (AREA)
Abstract
The invention discloses a manufacturing method of a bidirectional fiber grating, a bidirectional tracker and a passive network. The manufacturing method comprises the steps of irradiating laser on a mask area of a phase mask plate, and enabling the laser to expose the optical fiber through the mask area so as to form a first chirped grating and a second chirped grating on the optical fiber; the center wavelengths of the first chirped grating and the second chirped grating are the same, and the chirp rates of the first chirped grating and the second chirped grating are the same; the grating period of the first chirped grating is gradually increased from one end of the optical fiber to the other end of the optical fiber; the grating period of the second chirped grating is gradually increased from the other end of the optical fiber to one end of the optical fiber; and the grating period of the first chirped grating and the grating period of the second chirped grating are symmetrically distributed on the optical fiber. The bidirectional tracker can be obtained by the manufacturing method. The passive network includes the two-way tracker. The invention increases the flexibility and operability of optical link detection.
Description
Technical Field
The invention relates to the technical field of optical fiber communication, in particular to a manufacturing method of a bidirectional optical fiber grating, a bidirectional tracker based on the bidirectional optical fiber grating and a passive network.
Background
In an Optical access network, OTDR (Optical Time Domain Reflectometer) technology is often used to detect a network so as to diagnose faults occurring in the network in Time. In such a detection method, the tracker is used at the end of the optical link, so that the optical link with branches can be detected, and the operation and maintenance capability of the network can be improved.
Because the chirped grating has the characteristic of small influence on a communication waveband, the chirped grating is manufactured into the tracker as a preferable scheme in practical application and is widely deployed. The chirped grating may be made into a tracker for OTDR detection of an optical link according to the packaging method of the related patent (chinese patent application No. 201210358287.6).
The chirped grating is a fiber grating formed by gradually changing the period of the refractive index change of the core of the fiber (i.e., the grating period) along the axial direction of the fiber. The chirped grating can reflect incident light with different wavelengths at different axial positions, so that the chirped grating has a larger reflection bandwidth.
Also for this reason, chirped gratings have a large wavelength end and a small wavelength end: when an optical signal passes through, there are two cases where light is incident from the large wavelength end and light is incident from the small wavelength end. In both cases, the chirped grating has distinct reflection spectra. When light is incident from the small wavelength end of the chirped grating, a flat reflection spectrum can be obtained within a required bandwidth; when light is incident from the large wavelength end of the chirped grating, the resulting reflection spectrum is not flat. Since the wavelength and the nominal value of the detection light emitted by the OTDR have a deviation and are distributed in a certain range, the spectrum of the chirped grating defines the direction in which the tracker is used, i.e. only when the OTDR detection light is incident from the small wavelength end of the chirped grating, a flat reflection spectrum can be obtained in the required wavelength range. In contrast, when the OTDR detection light is incident from another direction, the resulting reflection spectrum is not flat. The unevenness of the reflection spectrum means that the reflectivity of the fiber grating to incident detection light with different wavelengths has a large difference, thereby affecting the final detection result of the optical link.
Disclosure of Invention
The invention aims to solve the technical problem that the reflectivity of the fiber grating to incident detection light with different wavelengths in two incident directions is greatly different in the prior art, and provides a manufacturing method of a bidirectional fiber grating, a bidirectional tracker based on the bidirectional fiber grating and a passive network.
In order to solve the technical problems, the invention adopts the following technical scheme:
the manufacturing method of the bidirectional fiber grating comprises the following steps:
irradiating laser on a mask area of a phase mask plate, and enabling the laser to expose the optical fiber through the mask area so as to form a first chirped grating and a second chirped grating on the optical fiber;
the center wavelengths of the first chirped grating and the second chirped grating are the same, and the chirp rates of the first chirped grating and the second chirped grating are the same;
the grating period of the first chirped grating is gradually increased from one end of the optical fiber to the other end of the optical fiber;
the grating period of the second chirped grating is gradually increased from the other end of the optical fiber to one end of the optical fiber;
and the grating period of the first chirped grating and the grating period of the second chirped grating are symmetrically distributed on the optical fiber.
In some preferred embodiments, the mask regions include a first mask region and a second mask region; the laser is simultaneously irradiated on the first and second mask regions to simultaneously fabricate the first and second chirped gratings.
In a further preferred embodiment, the phase mask includes a first mask and a second mask spliced together, the first mask area is located on the first mask, and the second mask area is located on the second mask.
In a further preferred embodiment, the lengths of the first mask region and the second mask region are both L ', the distance between the first mask region and the second mask region is d', the length of the fiber grating is S ', S' + 2L ', S' ≦ 16 mm.
In another aspect, the present invention provides a bidirectional tracker based on a bidirectional fiber grating, including a mounting component and a fiber grating disposed on the mounting component, where the fiber grating includes a first chirped grating and a second chirped grating, the first chirped grating and the second chirped grating have the same center wavelength and the same chirp rate, a grating period of the first chirped grating gradually increases from one end of the fiber to the other end of the fiber, a grating period of the second chirped grating gradually increases from the other end of the fiber to the one end of the fiber, and the grating period of the first chirped grating and the grating period of the second chirped grating are symmetrically distributed on the fiber.
In some preferred embodiments, the mounting assembly is provided with a cavity, the length of the cavity is D, the lengths of the first chirped grating and the second chirped grating are L, the distance between the first chirped grating and the second chirped grating is D, the length of the fiber grating is S, S is 2L + D, and S is not greater than D.
In a further preferred embodiment, the mounting assembly includes a first ferrule, a second ferrule and a connector, the first ferrule and the second ferrule being inserted into both ends of the connector, respectively; the first ferrule is provided with a first cavity, the second ferrule is provided with a second cavity, the length of the first cavity is D1, the length of the second cavity is D2, and the cavity comprises the first cavity and the second cavity, and D1+ D2 is D.
In a further preferred embodiment, D.ltoreq.16 mm.
In a further preferred embodiment, the chirp rate is 10nm/cm or more and d is 2mm or more.
In another aspect, the present invention further provides a passive network, in which an optical line terminal, an optical splitter, and an optical network unit are sequentially disposed on an optical path, and the passive network further includes the above bidirectional tracker, and the bidirectional tracker is disposed on the optical splitter and/or the optical network unit.
Compared with the prior art, the invention has the beneficial effects that:
the reflectivity of the bidirectional tracker to incident detection light of different wavelengths is substantially the same, regardless of from which end of the bidirectional tracker (fiber grating) the detection light is incident. The directivity of the tracker is eliminated, and the flexibility and operability of optical link detection are increased.
Drawings
FIG. 1 is a schematic structural diagram of a fiber grating according to the present invention;
FIG. 2 is a schematic view of another structure of the fiber grating according to the present invention;
FIG. 3 is a schematic diagram of a bidirectional tracker according to the present invention;
FIG. 4 is a schematic diagram of a variation of the two-way tracker of the present invention;
FIG. 5 is a resulting reflectance spectrum using the two-way tracker of the present invention;
FIG. 6 is a reflectance spectrum obtained using a tracker of a comparative example;
FIG. 7 is another reflectance spectrum obtained using a tracker of a comparative example;
FIG. 8 is a reflectance spectrum obtained using a tracker of another comparative example;
FIG. 9 is another reflectance spectrum obtained using a tracker of another comparative example;
FIG. 10 is a reflectance spectrum obtained using a two-way tracker of the present invention with d < 0 mm;
FIG. 11 is a reflection spectrum obtained using the two-way tracker of the present invention with d 0. ltoreq.d.ltoreq.1 mm;
FIG. 12 is a reflection spectrum obtained using a two-way tracker of the present invention with d ≧ 2 mm;
FIG. 13 is a schematic structural diagram of a mask plate used in the method for manufacturing a bidirectional fiber grating according to the present invention;
FIG. 14 is a schematic structural diagram of another mask plate used in the method for manufacturing a bidirectional fiber grating according to the present invention;
FIG. 15 is a schematic structural diagram of a third mask plate used in the method for manufacturing a bidirectional fiber grating according to the present invention;
fig. 16 is a schematic structural diagram of a passive network according to the present invention.
Detailed Description
The embodiments of the present invention will be described in detail below. It should be emphasized that the following description is merely exemplary in nature and is not intended to limit the scope of the invention or its application.
Referring to fig. 3, the bidirectional fiber grating-based bidirectional tracker 100 includes a mounting component 1 and a fiber grating 2, wherein the mounting component 1 is used for fixing the fiber grating 2, that is, the fiber grating 2 is disposed on the mounting component 1.
Referring to fig. 1, the fiber grating 2 is a chirped grating, and is made of an optical fiber. The fiber grating 2 includes a first chirped grating 21 and a second chirped grating 22, and the first chirped grating 21 and the second chirped grating 22 have the same center wavelength and the same chirp rate.
Referring to fig. 1, the grating period of the first chirped grating 21 is gradually increased from small to large at one end 10A of the optical fiber 10 toward the other end 10B of the optical fiber 10, and the grating period of the second chirped grating 22 is gradually increased from small to large at the other end 10B of the optical fiber 10 toward the one end 10A of the optical fiber 10. The first chirped grating 21 and the second chirped grating 22 are both provided with light and dark alternate stripes, and the light stripe 211 and the dark stripe 212 of the first chirped grating 21 are gradually widened in the direction 101 along the axial direction of the optical fiber at one end 10A of the optical fiber 10; the light fringes 221 and the dark fringes 222 of the second chirped grating 22 are also gradually widened in the direction 102 along the fiber axial direction at the other end 10B of the optical fiber 10. Or, since the grating period corresponds to the wavelength of light, the direction of the first chirped grating 21 is from a small wavelength to a large wavelength in the direction 101 along the axial direction of the optical fiber at the end 10A of the optical fiber 10; in the direction 102 along the fiber axial direction at the other end 10B of the optical fiber 10, the second chirped grating 22 is also oriented from a small wavelength to a large wavelength.
Referring to fig. 1, the grating period of the first chirped grating 21 and the grating period of the second chirped grating 22 are symmetrically distributed on the optical fiber 10. That is, the first chirped grating 21 and the second chirped grating 22 are two identical chirped gratings, both of which are symmetrically distributed on the optical fiber 10.
Referring to fig. 1, detection light, which may be OTDR-emitted detection light, is incident from an end 10A of an optical fiber 10, and is reflected back at a first chirped grating 21 and a second chirped grating 22, and a reflection spectrum is obtained on a spectrometer; when the detection light from the OTDR is incident from the other end 10B of the optical fiber 10 and is reflected back at the second chirped grating 22 and the first chirped grating 21, another reflection spectrum is obtained on the spectrometer. Referring to fig. 5, the two reflectance spectra are substantially identical, the left and right sides of the reflectance spectra are substantially symmetrical, and the top of the reflectance spectra are flat.
As can be seen from the above, the wavelength of the detection light emitted from the OTDR is about 1650nm, and the reflectance of the bidirectional tracker 100 to the incident detection light of different wavelengths is substantially the same regardless of which end of the bidirectional tracker (fiber grating) the detection light enters. Referring to FIG. 5, the reflectance of the two-way tracker for detection light with wavelengths of 1645nm to 1655nm is substantially the same. In this way, almost the same flat reflection spectrum can be obtained. Thus, through two sections of chirped grating cascades (cascades) with opposite directions, the directivity of the manufactured tracker is eliminated, and the flexibility and operability of optical link detection are improved.
The inventors have also tried to make trackers as follows:
the grating period of the first chirped grating 21 gradually decreases from large at the one end 10A of the optical fiber 10 toward the other end 10B of the optical fiber 10, and the grating period of the second chirped grating 22 gradually decreases from large at the other end 10B of the optical fiber 10 toward the one end 10A of the optical fiber 10. Referring to fig. 6 and 7, the two resulting reflectance spectra, although substantially identical, have undulating tops that are not useful for detecting optical links.
The grating period of the first chirped grating 21 gradually decreases from large at the one end 10A of the optical fiber 10 toward the other end 10B of the optical fiber 10, and the grating period of the second chirped grating 22 gradually increases from small at the other end 10B of the optical fiber 10 toward the one end 10A of the optical fiber 10. Referring to fig. 8 and 9, the two resulting reflectance spectra are very different, one of which is undulating in top and the other of which is flat, and such trackers are directional. Similarly, the tracker has directivity in the case where the grating period of the first chirped grating 21 gradually increases from small to large at the one end 10A of the optical fiber 10 toward the other end 10B of the optical fiber 10, and the grating period of the second chirped grating 22 gradually decreases from large to small at the other end 10B of the optical fiber 10 toward the one end 10A of the optical fiber 10.
The invention can also be realized as follows:
referring to fig. 3, the mounting assembly 1 of the two-way tracker 100 is provided with a cavity 14. Locations in the mounting assembly 1 other than the cavity 14 are used to secure the optical fiber 10, such as by securing the optical fiber 10 with potting compound at these locations. The fiber grating 2 is made of an optical fiber 10, i.e. the fiber grating 2 is a section of the optical fiber 10. The fiber 10 is mounted on the mounting assembly 1 with the fiber grating 2 in the cavity 14 and the length of fiber 10, i.e. the fiber grating 2, in a free state. The length of the cavity 14 is D, the lengths of the first chirped grating 21 and the second chirped grating 22 are L, the distance between the first chirped grating 21 and the second chirped grating 22 is D, the length of the fiber grating 2 is S, S is 2L + D, and S is equal to or less than D. This allows the fiber grating 2 to be entirely located in the cavity 14, which prevents the fiber grating 2 from being used to fix the optical fiber 10, and prevents the packaging glue used to fix the optical fiber 10 from flowing onto the fiber grating 2, thereby preventing the spectrum from changing and ensuring the quality of the spectrum.
Referring to fig. 4, one form of the mounting assembly 1 is: the mounting assembly 1 includes a first ferrule 11, a second ferrule 12, and a connector 13, and the first ferrule 11 and the second ferrule 12 are inserted into both ends of the connector 13, respectively. The first ferrule 11 is provided with a first cavity 110, the second ferrule 12 is provided with a second cavity 120, the length of the first cavity 110 is D1, and the length of the second cavity 120 is D2. The cavity 14 includes a first cavity 110 and a second cavity 120 and D1+ D2 ═ D, that is, the first cavity 110 and the second cavity 120 combine to form the cavity 14.
Referring to fig. 4, the first ferrule 11 and the second ferrule 12 fix the optical fiber 10 such that the first chirped grating 21 and the second chirped grating 22 are approximately located in the first cavity 110 and the second cavity 120, respectively. The specific way of fixing the optical fiber 10 by the first ferrule 11 and the second ferrule 12 is as follows: the first ferrule 11 is provided with a first front end inner hole 111, the second ferrule 12 is provided with a second front end inner hole 121, one end 10A of the optical fiber 10 is fixed in the first front end inner hole 111 through packaging glue, and the other end 10B of the optical fiber 10 is fixed in the second front end inner hole 121 through packaging glue. Generally, the outer diameters of the first ferrule 11 and the second ferrule 12 are of the millimeter order, and the inner diameters of the first front end inner bore 111 and the second front end inner bore 121 are of the micrometer order; illustratively, the outer diameters of the first ferrule 11 and the second ferrule 12 are 1mm to 5mm, and the inner diameters of the first front end inner bore 111 and the second front end inner bore 121 are 100 micrometers to 200 micrometers, which can meet the requirements of various applications.
Referring to fig. 2, the lengths of the first chirped grating 21 and the second chirped grating 22 are L, the distance between the first chirped grating 21 and the second chirped grating 22 is D, the length of the fiber grating 2 is S, S is 2L + D, and S is not greater than D1+ D2. Because the two ends of the optical fiber 10 are respectively fixed on the first ferrule 11 and the second ferrule 12, the length of the fiber bragg grating 2 is S less than or equal to D1+ D2, the packaging glue is prevented from flowing onto the fiber bragg grating 2, and the quality of the optical spectrum can be ensured.
The distance d between the first chirped grating 21 and the second chirped grating 22 has an influence on the overall reflection spectrum:
referring to FIG. 10, when the distance d is less than 0mm, i.e., the two chirped gratings partially overlap, the top of the reflection spectrum will fluctuate greatly. Referring to FIG. 11, when d is 0. ltoreq. d.ltoreq.1 mm, the slope of the large wavelength end of the reflection spectrum is largely fluctuated, but the top thereof is flat. Referring to FIG. 12, when the distance d is greater than or equal to 2mm, the waveforms of the slopes at both ends of the reflection spectrum are ideal, and the top is flat.
In practical application, considering the package of the tracker, the length L of the chirped grating is usually less than or equal to 8mm, and the wavelength of the detection light emitted by the conventional OTDR has a certain distribution range near its nominal value, which is mostly about 10nm, which requires a certain reflection bandwidth of the reflection spectrum. For fiber gratings, the reflection bandwidth is chirp rate x length of the chirped grating x core index, where the core index is determined by the type of fiber used for the grating, e.g., 1.448, and for trackers having sufficient reflection bandwidth and being packaged with conventional dimensions, a chirp rate of the chirped grating of 10nm/cm or more is required.
Generally, the packaging size of the tracker is smaller than 22mm, and due to the limitation of the ferrule processing technology, when the cavity 14 is too deep, the concentricity between the inner hole at the front end of the ferrule and the outer diameter of the ferrule cannot be ensured. The concentricity can affect the alignment of the ferrules in butt joint, thereby affecting the insertion loss of the whole device. Therefore, to reduce insertion loss, the size of the cavity 14 is limited to D ≦ 16mm or D1+ D2 ≦ 16mm, i.e., both D1 and D2 are less than or equal to 8mm, such as 6 mm.
In another aspect, the present invention provides a method for fabricating a bidirectional fiber grating, which can be used to fabricate the fiber grating 2 described above, and can also be used to fabricate other fiber gratings.
Referring to fig. 13, laser light is irradiated on the mask region 30 of the phase mask plate 3, and the optical fiber 10 is exposed by the laser light through the mask region 30 to form the first and second chirped gratings 21 and 22 on the optical fiber 10. Mask field 30, i.e., the mask pattern, may be designed as desired. After the laser light passes through the mask region 30 to expose the optical fiber 10, stripes with alternate light and dark can be formed on the optical fiber 10.
Referring to fig. 1, during fabrication: the center wavelengths of the first chirped grating 21 and the second chirped grating 22 are the same, and the chirp rates are the same; the grating period of the first chirped grating 21 is gradually increased from one end 10A of the optical fiber 10 to the other end 10B of the optical fiber 10; the grating period of the second chirped grating 22 is gradually increased from the other end 10B of the optical fiber 10 to the one end 10A of the optical fiber 10; the grating period of the first chirped grating 21 and the grating period of the second chirped grating 22 are distributed symmetrically on the optical fiber 10.
In the fiber grating 2 thus obtained, the reflectance of the fiber grating 2 with respect to incident detection light of different wavelengths is substantially the same regardless of which end of the optical fiber 10 the light enters.
As described above, the outer diameters of the first ferrule 11 and the second ferrule 12 are on the millimeter scale, for example, 2.5mm, and the inner diameters of the first front end inner hole 111 and the second front end inner hole 121 are on the micrometer scale, for example, 125 μm, which increases the difficulty in packaging the fiber grating 2, for example, to prevent the package adhesive for fixing the end face of the optical fiber 10 from flowing onto the fiber grating 2, thereby obtaining a high reflectivity. In order to reduce the processing difficulty, the exposure time of the laser to the optical fiber 10 is increased when the fiber grating is manufactured, so that higher reflectivity is obtained.
The invention can also be realized as follows:
referring to fig. 14, mask region 30 includes a first mask region 31 and a second mask region 32; the laser light is simultaneously irradiated on the first and second mask regions 31 and 32 to simultaneously fabricate the first and second chirped gratings 21 and 22, which may improve fabrication efficiency.
Referring to fig. 15, the phase mask plate 3 includes a first mask plate 3A and a second mask plate 3B which are spliced together, a first mask area 31 is located on the first mask plate 3A, and a second mask area 32 is located on the second mask plate 3B. Of course, the phase mask 3 may also be a one-piece mask, on which the first mask area 31 and the second mask area 32 are provided.
Referring to fig. 14, the distance d 'between the first mask region 31 and the second mask region 32 is approximately equal to the distance d between the first chirped grating 21 and the second chirped grating 22, and the distance d' is also equal to or greater than 0mm in order to obtain a reflection spectrum with a flat top of the spectrum.
The first mask plate 3A and the second mask plate 3B are mask plates having the same thickness, and the thickness tolerance thereof affects not only the generation of the chirp effect but also the quality of the two reflection spectra, and therefore, the thickness tolerance of the first mask plate 3A and the second mask plate 3B is within ± 0.05 mm.
Referring to fig. 14, the lengths of the first mask region 31 and the second mask region 32 are L ', the fiber grating length S ' is 2L ' + d ', and the fiber grating length S ', i.e. the size of S, S ', affects the length of the cavity of the ferrule, as mentioned above, to reduce the insertion loss, S ' is less than or equal to 16 mm.
In another aspect, the present invention also provides a passive network, which is provided with an optical line terminal 4, an optical splitter 5, and an optical network unit 6 in this order on an optical path, with reference to fig. 16. The optical splitter 5 is in multiple stages, for example, two stages of optical splitters 5 are provided, and accordingly, the number of the optical network units 6 is multiple. The optical signal enters from the optical line terminal 4, passes through the two-stage optical splitter 5, and finally enters into the plurality of optical network units 6.
The passive network further comprises a bidirectional tracker 100 as described above, the bidirectional tracker 100 being arranged on the optical splitter 5 and/or on the optical network unit 6.
In the passive network, the two-way tracker 100 will have different connections at different locations:
at splitter 5, the fiber is placed on an adapter port left on the cabinet panel, and the bidirectional tracker 100 is mounted back on the adapter port.
At the optical network unit 6, the optical fiber is placed on an adapter port on the optical network unit 6, on which the bidirectional tracker 100 is mounted in the forward direction.
The above are typical locations and scenarios for the installation of the two-way tracker 100. In actual use, the installation mode is also available according to different situations of network deployment. The present invention allows the two-way tracker 100 to be installed in any position on the network in any orientation, increasing the flexibility and operability of network detection and maintenance.
The foregoing is a more detailed description of the invention in connection with specific/preferred embodiments and is not intended to limit the practice of the invention to those descriptions. It will be apparent to those skilled in the art that various substitutions and modifications can be made to the described embodiments without departing from the spirit of the invention, and these substitutions and modifications should be considered to fall within the scope of the invention.
Claims (10)
1. The manufacturing method of the bidirectional fiber grating is characterized by comprising the following steps:
irradiating laser on a mask area of a phase mask plate, and enabling the laser to expose the optical fiber through the mask area so as to form a first chirped grating and a second chirped grating on the optical fiber;
the center wavelengths of the first chirped grating and the second chirped grating are the same, and the chirp rates of the first chirped grating and the second chirped grating are the same;
the grating period of the first chirped grating is gradually increased from one end of the optical fiber to the other end of the optical fiber;
the grating period of the second chirped grating is gradually increased from the other end of the optical fiber to one end of the optical fiber;
the grating period of the first chirped grating and the grating period of the second chirped grating are symmetrically distributed on the optical fiber;
the bidirectional fiber grating satisfies the following conditions: the bi-directional fiber grating has substantially the same reflectivity for different wavelengths of incident detection light regardless of which end of the optical fiber the incident detection light is incident from.
2. The method of manufacturing according to claim 1, wherein: the mask regions include a first mask region and a second mask region; the laser is simultaneously irradiated on the first and second mask regions to simultaneously fabricate the first and second chirped gratings.
3. The method of manufacturing according to claim 2, wherein: the phase mask plate comprises a first mask plate and a second mask plate which are spliced together, wherein the first mask area is positioned on the first mask plate, and the second mask area is positioned on the second mask plate.
4. The manufacturing method according to claim 2 or 3, characterized in that: the lengths of the first mask area and the second mask area are both L ', the distance between the first mask area and the second mask area is d ', the length of the fiber grating is S ', S ' is 2L ' + d ', and S ' is less than or equal to 16 mm.
5. Bidirectional tracker based on bidirectional fiber grating, including installation component and setting up the fiber grating on installation component, characterized by: the fiber bragg grating comprises a first chirped grating and a second chirped grating, the center wavelengths of the first chirped grating and the second chirped grating are the same, the chirp rates of the first chirped grating and the second chirped grating are the same, the grating period of the first chirped grating is gradually increased from one end of the optical fiber to the other end of the optical fiber, the grating period of the second chirped grating is gradually increased from the other end of the optical fiber to one end of the optical fiber, and the grating period of the first chirped grating and the grating period of the second chirped grating are symmetrically distributed on the optical fiber; the fiber grating satisfies: the reflectivity of the fiber grating to different wavelengths of incident detection light is substantially the same regardless of which end of the optical fiber the incident detection light is incident from.
6. The two-way tracker according to claim 5, wherein: the optical fiber grating mounting structure is characterized in that the mounting component is provided with a cavity, the length of the cavity is D, the length of the first chirped grating and the length of the second chirped grating are L, the distance between the first chirped grating and the second chirped grating is D, the length of the optical fiber grating is S, S is 2L + D, and S is less than or equal to D.
7. The two-way tracker according to claim 6, wherein: the mounting assembly comprises a first inserting core, a second inserting core and a connecting piece, and the first inserting core and the second inserting core are respectively inserted into two ends of the connecting piece; the first ferrule is provided with a first cavity, the second ferrule is provided with a second cavity, the length of the first cavity is D1, the length of the second cavity is D2, and the cavity comprises the first cavity and the second cavity, and D1+ D2 is D.
8. The two-way tracker according to claim 6 or 7, characterized in that: d is less than or equal to 16 mm.
9. The two-way tracker according to claim 6, wherein: the chirp rate is more than or equal to 10nm/cm, and d is more than or equal to 2 mm.
10. A passive network, characterized by: an optical line terminal, an optical splitter and an optical network unit are arranged on an optical path in sequence, and the optical network unit further comprises a bidirectional tracker according to any one of claims 5 to 9, wherein the bidirectional tracker is arranged on the optical splitter and/or the optical network unit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810778188.0A CN108768526B (en) | 2018-07-16 | 2018-07-16 | Bidirectional fiber grating manufacturing method, bidirectional tracker and passive network |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810778188.0A CN108768526B (en) | 2018-07-16 | 2018-07-16 | Bidirectional fiber grating manufacturing method, bidirectional tracker and passive network |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108768526A CN108768526A (en) | 2018-11-06 |
| CN108768526B true CN108768526B (en) | 2020-01-07 |
Family
ID=63974023
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810778188.0A Active CN108768526B (en) | 2018-07-16 | 2018-07-16 | Bidirectional fiber grating manufacturing method, bidirectional tracker and passive network |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108768526B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2020014814A1 (en) * | 2018-07-16 | 2020-01-23 | 深圳太辰光通信股份有限公司 | Method for manufacturing bidirectional fiber grating, bidirectional tracker, and passive network |
| CN111766654A (en) * | 2020-06-16 | 2020-10-13 | 复旦大学 | Gold grating for realizing ultrahigh extinction ratio coefficient and preparation method thereof |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA2244572A1 (en) * | 1997-08-12 | 1999-02-12 | Photonics Research Ontario | Design of complex optical fiber filters using long-period gratings |
| CA2340913C (en) * | 1998-08-19 | 2004-09-14 | Samsung Electronics Co., Ltd. | Apparatus for manufacturing long-period fiber gratings and apparatus for manufacturing two-band long-period fiber gratings using the same |
| GB2381083A (en) * | 2001-10-18 | 2003-04-23 | Fujitsu Network Communications | Optical distributed chirped grating with reflection symmetry |
| CN103940360B (en) * | 2014-04-23 | 2016-10-05 | 鲁东大学 | A kind of strain monitoring device based on cascade chirped fiber grating |
| CN108233173A (en) * | 2016-12-22 | 2018-06-29 | 苏州旭创科技有限公司 | Unsymmetric structure phase-shifted grating and DFB semiconductor laser |
| CN107246931B (en) * | 2017-07-11 | 2020-03-10 | 中国矿业大学 | Fiber bragg grating transverse stress strain sensor and detection method |
-
2018
- 2018-07-16 CN CN201810778188.0A patent/CN108768526B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN108768526A (en) | 2018-11-06 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US7654750B2 (en) | Bidirectional optical fiber link systems component couplers | |
| US9983361B2 (en) | GRIN-lensed, tuned wedge waveguide termination and method of reducing back reflection caused thereby | |
| EP1579257B1 (en) | Optical fiber lens and method of manufacture | |
| US8885992B2 (en) | Optical reception module and method of manufacturing optical reception module | |
| US20020041735A1 (en) | Multiple grating optical waveguide monitor | |
| CA1260163A (en) | Wave-division multiplex component for an optical network comprising monomode transmission fibers | |
| KR20040015329A (en) | Hybrid fiber expanded beam connector and methods for using and making the hybrid fiber expanded beam connector | |
| US8655181B2 (en) | Optical transmission/reception module | |
| US20060067616A1 (en) | Pseudo slant fiber bragg grating, multiple series fiber bragg grating, optical fiber type coupler and optical connector | |
| CN108768526B (en) | Bidirectional fiber grating manufacturing method, bidirectional tracker and passive network | |
| US10215624B2 (en) | Integrated optical tap monitor | |
| CN111051843B (en) | Optical fiber | |
| CN102621643A (en) | Single-core bidirectional optical communication module and manufacturing method thereof | |
| JP2019197207A (en) | Single-wavelength bidirectional transceiver with integrated optical fiber coupler | |
| Ford et al. | Optical fiber-coupled variable attenuator using a MARS modulator | |
| EP0962794A1 (en) | Article comprising a dispersive waveguide tap | |
| EP1507153A1 (en) | Signal cutout device, optical connector, and optical fiber coupler | |
| KR20130120624A (en) | Optical connector assembly and assembling method thereof | |
| CN101131454A (en) | Optical receptacle and optical receptacle module therewith | |
| WO2002019002A1 (en) | Polarizer-equipped optical fiber ferrule, connector and connector adaptor | |
| WO2020014814A1 (en) | Method for manufacturing bidirectional fiber grating, bidirectional tracker, and passive network | |
| KR101674005B1 (en) | Single Wavelength Bi-directional Optical Sub-Assembly | |
| CN208522758U (en) | Direction tracing device and passive network based on bidirectional optical fiber grating | |
| JP3110637U (en) | Light reflecting element | |
| JPH09135206A (en) | Optical communication system |
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 |