One kind inscribing any grid region length of fibre grating approach based on adjustable diaphragm
Technical field
The present invention relates to technical field of optical fiber, in particular to a kind of to inscribe any grid region length of fibre light based on adjustable diaphragm
Grid method.
Background technique
Fiber bragg grating (abbreviation fiber grating), the photonic device one of mostly important as 21st century, with
Its small in size, high sensitivity, Wavelength-encoding, electromagnetism interference, with optical fiber be seamlessly connected the advantages that, Fibre Optical Sensor, communication and
It is widely applied in the fields such as optical fiber laser.
Chinese patent 201310228540.0 discloses a kind of fiber grating carving and writing method and device that bandwidth is controllable, China
Patent 201510213965.3 discloses a kind of device and method for inscribing period adjustable optic fibre grating, but with fiber grating
Extensive use in fields such as Fibre Optical Sensor, communication and optical fiber lasers, it is also different to the length requirement of fiber grating, because
This designs a kind of preparing grating method that inscription length is controllable and has become a hot topic of research to meet requirement of engineering.
Summary of the invention
Any grid region length of fibre grating approach is inscribed the object of the present invention is to provide a kind of, inscribes high-efficient, operation
Method is simple and reusable.
The technical scheme is that a kind of inscribe any grid region length of fibre grating approach, the party based on adjustable diaphragm
The device that method uses is made of laser, laser beam shaping system, phase mask plate, optical fiber and optical fiber clamping device, described
Laser beam shaping system include deviation mirror, expand microscope group, adjustable diaphragm and cylindrical lens, the detailed process of the carving and writing method is such as
Under:
Optical fiber is carried out to carry hydrogen processing, and removes its coat;
The laser of Shape correction is focused on phase mask plate through cylindrical lens, transmitted light generates ± 1 through phase mask plate
Grade diffraction, the interference light that diffraction light is formed are inscribed to by inscription exposed optical fiber.
Preferably, load hydrogen processing includes: to be placed in optical fiber in the load hydrogen pond of preset air pressure and temperature, makes the optical fiber
Middle formation hydrogen-germanium chemical bond.
Preferably, the laser that the laser emits expands described in vertically injecting after 99% deviation mirror of surface coating
In microscope group, the deviation mirror and the laser direction of the launch are in 45 ° of angles.
Preferably, the exposure area to optical fiber is inscribed and real-time monitoring includes:
Wideband light source and spectrometer is respectively set in optical fiber both ends after the removal coat, examines in real time to scribing process
It surveys, setting is split as microscope below the optical fiber of the removal coat, is verified to fiber lengths.
Preferably, described to be specifically included according to inscription grating length adjustment diaphragm size: diaphragm parameter G size and grating
The relationship of grid region length L is linear relationship formula (1) expression:
L=kG (1)
Wherein k value is direct proportion coefficient, and diaphragm parameter G refers to diaphragm lateral dimension.
Preferably, the adjusting diaphragm specifically adjusts diaphragm horizontal direction distance, and method includes: with a series of tools
The lighttight shelter of body size blocks or selects the adjustable diaphragm of included adjustable dimension.
The beneficial effects of the present invention are: being inscribed based on phase mask plate to optical fiber, so that the fiber grating inscribed
Grid region length is not only restricted to inscribe the chirp degree of ultraviolet laser spot size and phase mask, that is, can reach grating grid region length can
The purpose of control, the efficiency for being effectively reduced cost of manufacture and this method inscription is higher, and repeatability is stronger.
Detailed description of the invention
With reference to the attached drawing of accompanying, the more purposes of the present invention, function and advantage are by the as follows of embodiment through the invention
Description is illustrated, in which:
Fig. 1 is the structural block diagram that the present invention inscribes any fiber grating grid region length device.
Fig. 2 is the structural schematic diagram that real-time monitoring of the present invention inscribes different length fiber grating.
Fig. 3 is the relation schematic diagram that diaphragm adjusting size and grating of the invention inscribe length.
Specific embodiment
By reference to exemplary embodiment, the purpose of the present invention and function and the side for realizing these purposes and function
Method will be illustrated.However, the present invention is not limited to exemplary embodiment as disclosed below;Can by different form come
It is realized.The essence of specification is only to aid in those skilled in the relevant arts' Integrated Understanding detail of the invention.
Hereinafter, the embodiment of the present invention will be described with reference to the drawings.In the accompanying drawings, identical appended drawing reference represents identical
Or similar component or same or like step.
Embodiment 1
The present invention provides one kind to inscribe any grid region length of fibre grating approach based on adjustable diaphragm, specifically includes following
Step: optical fiber carries out carrying hydrogen processing, after removing its coat, is installed on the controllable fiber grating Written Device of grid region length
On;The controllable fiber grating Written Device of the grid region length is by deviation mirror and expands the laser beam that microscope group emits laser
It deflecting and expands, the grating length in grid region is inscribed in the laser beam setting after expanding, and adjustable diaphragm is by one-dimensional movement platform electricity
Dynamic to control and connect by serial ports with computer, at upper computer software interface, input need to inscribe the grating length in grid region, according to quarter
Grating length adjustment diaphragm size is write, diaphragm adjusted is one-dimensional according to the Beam Control after shaping to received beam shaping
The exposure area of electric platforms adjusting optical fiber.Optical fiber is inscribed based on phase mask plate, so that the fiber grating inscribed
Grid region length is not only restricted to inscribe the chirp degree of ultraviolet laser spot size and phase mask, that is, can reach grating grid region length can
The purpose of control, the efficiency for being effectively reduced cost of manufacture and this method inscription is higher, and repeatability is stronger.
The present invention provides one kind to inscribe any grid region length of fibre grating approach based on adjustable diaphragm, and scribing process is specific
The following steps are included:
Optical fiber is carried out to carry hydrogen processing, and removes its coat.
Optical fiber is placed in the load hydrogen of the load hydrogen Chi Zhongjing of preset air pressure and temperature after a period of time, makes to be formed in the optical fiber
Hydrogen-germanium (H-Ge) chemical bond, in order to which optical fiber quickly inscribes optical fiber at grid;Optical fiber wire stripper are recycled to remove the optical fiber
Coat, it is generally the case that go coating layer region length be no less than 20cm, go coating layer region length covered greater than phase
The length of diaphragm plate.
The laser beam shaping processing that laser 101 is emitted.
Laser beam shaping system includes deviation mirror 102, expands microscope group 103, adjustable diaphragm 104 and cylindrical lens 105, adjustable
Diaphragm 104 is by 109 Electronic control of one-dimensional movement platform and adjustable diaphragm 104 is connect by serial ports with computer 110;Laser
It the diverted mirrors of laser beam 102 of 101 transmittings and expands microscope group 103 and expands, by the laser beam after expanding in computer software
Interface input is quasi- to inscribe grating grid region length, according to the width of grid region length adjustment adjustable diaphragm 104;After adjustable diaphragm is to expanding
Laser beam shaping processing.
Cost in the embodiment of the present invention to reduce fiber grating inscription, it is ensured that inscription fiber grating grid region length is controllable,
It needs to emit laser 101 laser beam and carries out shaping, it is specific: using deviation mirror 102 and to expand microscope group 103 to the laser
The laser for the predetermined wavelength (for example, ultraviolet laser of 248nm) that device 101 emits is expanded;It is being connect by serial ports with diaphragm
The quasi- grating grid region length for needing to inscribe of computer software interface input;It is wide according to the grating grid region length adjustment diaphragm of input
It spends and shaping is carried out to the laser beam received while passing through the one-dimensional movement adjusting of platform 109 exposure area;Cylindrical lens 105 will
The laser beam focusing of the shaping received.
Preferably, deviation mirror 102 is 99% high reflection mirror of a surface coating, and the deviation mirror and laser launch party
To being in 45 ° of angles, it is finely adjusted for changing laser optical path and to laser optical path.
Preferably, computer software interface setting grating grid region length and diaphragm parameters relationship program, input grating grid region
Diaphragm parameter is calculated by software in length, and the relationship of diaphragm parameter G size and grating grid region length L are linear relationship formula
(1) it indicates:
L=kG (1)
Preferably, the one-dimensional movement platform 109 is controlled by controller, may be implemented at the uniform velocity to move, and realizes grid region
Length is uniformly inscribed.
Light beam after focusing inscribes the exposure area of the optical fiber by phase mask plate 106, obtains required light
Fine grating.
For phase mask plate 106 for generating ± l grades of diffraction light, diffraction light is alternatively formed interference fringe, to exposure area into
Row is inscribed, and fiber grating is obtained.
FBG monitoring and detection in scribing process.
Fig. 2 shows the structure charts that real-time monitoring of the present invention inscribes different length fiber grating.As shown in Fig. 2, described
Wideband light source 220 (such as ASE wideband light source), spectrometer 230 and spectrometer is respectively set in optical fiber both ends after removal coat
231, spectrometer 230 and spectrometer 231 monitor reflectance spectrum and transmitted spectrum respectively, and it is (right to carry out real-time monitoring to scribing process
Optical grating reflection spectrum carries out real-time monitoring with transmission spectrum in different length grating scribing process), wideband light source 220 and spectrometer 230
It is connect with 210 port 1 of coupler and port 2, spectrometer 231 is connect with optical fiber one end, the optical fiber other end and 210 port of coupler
3 connections, setting is split as microscope 240 below the optical fiber 108 of removal coat, is verified and is detected to grating length.
Embodiment 2
Fig. 1 is a kind of structural block diagram for inscribing any fiber grating grid region length device that the embodiment of the present invention 2 provides.Such as
Shown in Fig. 1, which includes: laser 101, deviation mirror 102, expands microscope group 103, adjustable diaphragm 104, cylindrical lens 105, phase
Mask plate 106, optical fiber 108 and optical fiber clamping device 107.
The laser 101 is used to emit the laser of predetermined wavelength.
The cylindrical lens 105 are focused processing for the laser to Shape correction.
The deviation mirror 102, is finely adjusted for changing laser optical path and to laser optical path.
It is described to expand microscope group 103, for expanding shaping to laser beam.
The phase mask plate 105, for being inscribed using exposure area of the laser after focus processing to the optical fiber.
The optical fiber clamping device 107 and optical fiber contact face is equipped with rubber pad, it is ensured that frictional force effect does not make optical fiber
At damage;The optical fiber clamping device is for fixing and positioning optical fiber.
The adjustable diaphragm 104 receives the laser beam after shaping and to laser beam Shape correction again;It is described adjustable
Diaphragm 104 is round, rectangle or square, depending on inscribing actual conditions;The adjustable diaphragm 104 is placed in one-dimensional shifting
109 top of moving platform, diaphragm is changed by the horizontal position that one-dimensional movement 109 Electronic control of platform adjusts diaphragm to be gone to coat
The exposure area of layer optical fiber 108, the one-dimensional movement platform 109 are controlled by controller, can at the uniform velocity be moved and be realized that grid region is long
Degree is uniformly inscribed;The adjustable diaphragm 104 is connect by serial ports with computer 110, and user is quasi- by inputting in software interface
Grating grid region length is inscribed to adjust diaphragm size;The method that the adjustable diaphragm 104 adjusts diaphragm width includes: with opaque
The shelter with specific size block the light of through-hole (such as cloth or wooden unit etc. of specific size) or included adjustable dimension
Door screen changes aperture stop size (such as aperture in photographic lens) by adjusting handle.
In conjunction with the explanation and practice of the invention disclosed here, the other embodiment of the present invention is for those skilled in the art
It all will be readily apparent and understand.Illustrate and embodiment is regarded only as being exemplary, true scope of the invention and purport are equal
It is defined in the claims.