CN203326346U - Cladding light filtering structure - Google Patents
Cladding light filtering structure Download PDFInfo
- Publication number
- CN203326346U CN203326346U CN2013202512274U CN201320251227U CN203326346U CN 203326346 U CN203326346 U CN 203326346U CN 2013202512274 U CN2013202512274 U CN 2013202512274U CN 201320251227 U CN201320251227 U CN 201320251227U CN 203326346 U CN203326346 U CN 203326346U
- Authority
- CN
- China
- Prior art keywords
- coating
- light
- cladding
- filter
- segmentation
- 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.)
- Expired - Lifetime
Links
Images
Abstract
The utility model discloses a cladding light filtering structure which is used for filtering cladding light in a dual-cladding or multi-cladding optical-fiber laser system. The cladding light filtering structure comprises an optical fiber, and a light-filtering material coating on a glass cladding, wherein a protection layer of the optical fiber and an out cladding of the optical fiber are stripped, and a segment of the glass cladding is exposed. The refractive index of a light-filtering material is higher than that of the outer cladding of the optical fiber. The light-filtering material coating is a coating which is coated with the light-filtering material in a manner of segmentation. In the utility model, a material refractive index, a coating length and a coating interval are filtered through matching, thereby enabling light-filtering amount of each segment to be roughly the same, reducing highest temperature jump of a filter in the working condition, and improving reliability of a system. The more the number of segments and the varieties of materials are, the better the effect is.
Description
Technical field
The utility model relates to fiber laser or fiber amplifier, particularly a kind of filtering of the cladding light for fiber laser or fiber amplifier structure and preparation method thereof.
Technical background
The fiber laser power output constantly promotes, and has realized at present the above power output of separate unit myriawatt.So high power output mainly has benefited from the development of optical fiber and pumping source technology.Generally, fiber laser or the fiber amplifier of power output over 1 watt all can adopt double-cladding active optical fiber as gain fibre.So-called doubly clad optical fiber, generally by fibre core 6, glass-clad 5 and low-refraction surrounding layer 4, and optional polymolecular polymer protective layer 3 compositions, as Fig. 1.Near the polymolecular polymer of normally a kind of refractive index of low-refraction surrounding layer 4 1.36.The refractive index of fibre core 6, generally higher than the refractive index of glass-clad 5, guarantees that flashlight transmits in fibre core.Pump light is usually in glass-clad 5 and the interior transmission of fibre core 6, and after the boundary reflection of inner cladding and surrounding layer by fibre core, if fibre core doped with rare earth element, this part pump light by fibre core can be absorbed.
Generally, in fiber laser or fiber amplifier, the unnecessary light energy in the glass-clad of gain fibre output mainly contains three sources:
1) there is no absorbed remnant pump light.In the situation that pump light is absorbed by fibre core, pumping light power is exponential damping trend along optical fiber.Because fiber lengths necessarily causes, in laser cavity or amplifier out, remnant pump light is arranged.
2) cladding signal light.The flashlight transmitted in fiber core can be because optical fiber macrobend, micro-curved or fusion point Insertion Loss etc. are former thereby be leaked to covering from fibre core.
3) (ASE) light is amplified in the spontaneous radiation of covering.In the situation that gain media is energized, ASE light always there will be.Usually remnant pump light and the numerical aperture of ASE light when inner cladding transmits are larger, and the numerical aperture of cladding signal light is less.
If the unnecessary cladding light of gain fibre output does not leach, can cause the optical quality of exporting light to descend, thereby affect working effect.Under specific circumstances, the unnecessary light energy of these large-numerical apertures may absorb to certain or some devices laser cutting/plumb joint from the Laser output head, causes local temperature too high, produces the integrity problem of device.
Unnecessary cladding light processing scheme, mainly contain that interface leaches, Interface Absorption or the two mix three kinds of forms.For leaching scheme, generally adopt at present on nuditing fiber or single cladded fiber surface, concentrate one section single filter of planting of coating.Due to the approximate index law decay in filter layer of unnecessary cladding light, therefore above-mentioned coat is very large at a bit of interior concentrated absorption heat of beginning, causes local temperature too high, greatly limits it and leaches ability.
Along with fiber laser or amplifier output power are constantly climbed to a higher point, the absolute magnitude of the unnecessary inner cladding light that need to leach also constantly rises, so single concentrated optical filtering scheme that applies of material of planting becomes one of bottleneck that affects fiber laser or output power for fibre amplifier lifting.
Summary of the invention
The purpose of this utility model is to provide a kind of filtering of the cladding light for fiber laser or fiber amplifier structure and preparation method thereof, this structure can leach the cladding light of fiber laser or fiber amplifier, leach maximum operating temperature a little thereby reduce, with long-term working stability and the reliability of elevator system.
Technical solution of the present utility model is as follows:
A kind of cladding light filtering structure; comprise and divested protective layer, surrounding layer; the optical fiber of exposed one section glass-clad and the filter coating on this glass-clad; its characteristics are the refractive index of the refractive index of described filter higher than the surrounding layer of described optical fiber, and the coating of described filter is the coating of more than one filters and segmentation coating.
Described filter coating is the coating segmentation with same filter segmentation coating, and the interval between each coating segmentation is greater than zero, and the length of each coating segmentation is by short gradually long, with reach each coating segmentation to leach light relatively even.
Described filter coating is that the filter different with two or more respectively is coated in the coating segmentation successively, equal zero or be greater than zero in interval between each coating segmentation, the refractive index of the filter of each coating segmentation is by little gradually large, with reach each coating segmentation to leach light relatively even.
Described optical fiber is single cladded fiber, doubly clad optical fiber or multi-clad.
Described filter is for leaching the glass dust of low glue, index matching liquid or the low melting point of damaging of wave band cladding light to need.
The utility model principle
When light beam is propagated in optical fiber, the light of different transverse modes is different with the incidence angle on the surrounding layer interface in glass-clad, the refractive index of original surrounding layer is by the refractive index Proper Match with glass-clad, make the light of different incidence angles in certain limit all can meet total reflection condition, thereby corresponding pattern is transmitted in optical fiber.
According to fresnel's law, select the filter refractive index to be greater than the material of original cladding refractive index, can destroy the total reflection condition of part or all of pattern, and then part or all of cladding light can leak out via the interface of filter and glass-clad.
The cladding light part be filtered off scatters to space, and a part is absorbed by the filter of filter layer.Now, the cladding light leached descends along the approximate index law of Optical Fiber Transmission direction, that is:
Pdump=Pc*e
-a*l
In formula, Pdump means the power leached, and Pc means the gross power of transmission in covering, and a means the leach coefficient relevant with the filter refractive index, and l means filter coating length.
It is relevant that the heat Qdump produced and Pdump leach power linear:
Qdump=Pdump*b
In formula, b is relevant with the filter composition absorption coefficient that need is leached to wave band.
Therefore the heat of generation also will distribute according to similar rule, and in starting a bit of glass-clad filtered, heat is the most concentrated, and temperature is the highest, if adopt single kind material to concentrate, leach, and will produce higher temperature jump point.
The utility model adopts segmentation to leach scheme, by refractive index, coating length, the interval between coating of controlling filter, can control the optical filtering amount on unit length, make cladding light along being filtered off uniformly in light transmission direction certain-length, and then heat distributes and also will become relatively even, avoid occurring the too high situation of certain some temperature jump.Adopt the kind of filter more, filter coating segments is more, and Temperature Distribution is just more even.
Known by above-mentioned analysis, technique effect of the present utility model is as follows:
1, cladding light relatively evenly leaches along the light transmition direction;
2, can eliminate the phenomenon of the heat undue concentration of the cladding light section of leaching, greatly reduce the temperature jump point, make the upper Temperature Distribution of the section of leaching relatively even.
The accompanying drawing explanation
The existing cladding light of Fig. 1 leaches structural representation
The existing doubly clad optical fiber structure of Fig. 2 and refraction index profile schematic diagram
Fig. 3 is the optical filtering schematic diagram of more than a kind of filter segmentation continuously coating of the utility model embodiment
Fig. 4 is the single optical filtering schematic diagram of planting filter segmentation coating of the utility model embodiment 2
Fig. 5 embodiment 1 cladding light amount of leaching simulation curve figure
Fig. 6 embodiment 2 cladding light amount of leaching simulation curve figure
Embodiment
Below by embodiment and accompanying drawing, the utility model is described in further detail, but should not limit protection range of the present utility model with this.
First refer to Fig. 3, Fig. 3 is the optical filtering schematic diagram of more than a kind of filter segmentation continuously coating of the utility model embodiment, as seen from the figure, the present embodiment cladding light leaches structure, comprise and divested protective layer 3, surrounding layer 4, the optical fiber 2 of exposed one section glass-clad 5 and filter 1 coating on this glass-clad 5, the refractive index of described filter 1 is higher than the refractive index of the described surrounding layer 4 of described optical fiber 2, described filter 1 coating is respectively to be coated in successively the coating segmentation with five kinds of different filters, equal zero in interval between each coating segmentation, the refractive index of the filter of each coating segmentation is by little gradually large, with reach each coating segmentation to leach light relatively even.
Adopt fibre core 6 diameter 10um, interior glass-clad 5 diameter 125um, the silica fiber of surrounding layer 4 diameter 250um, divest protective layer 3 and surrounding layer 4, forms the nuditing fiber of 3cm.With reference to figure 3, filter 1, filter 28, filter 39, filter 4 10 are selected the glass powder with low melting point of refractive index between surrounding layer 4 refractive indexes and glass-clad 5 refractive indexes, filter 5 11 selects refractive index to be more than or equal to the glass dust of inner cladding refractive index, by 5 kinds of glass dust.According to aforementioned exponential formula, the coating interval is made as 0, and by optimizing refractive index and every section coating length, making every section, to leach coefficient ratio be 0.5:0.66:0.93:1.5:3.5.Experiment shows to leach the cladding light more than 99%, and cladding light filtering amount analog computation result as shown in Figure 5.
Embodiment 2
First refer to Fig. 4, Fig. 4 is the single optical filtering schematic diagram of planting filter segmentation coating of the utility model embodiment 2, as seen from the figure, the present embodiment cladding light leaches structure, comprise and divested protective layer 3, surrounding layer 4, the optical fiber 2 of exposed one section glass-clad 5 and filter 1 coating on this glass-clad 5, the refractive index of described filter 1 is higher than the refractive index of the described surrounding layer 4 of described optical fiber 2, described filter 1 coating is the coating segmentation with same filter segmentation coating, and the interval between each coating segmentation is greater than zero, the length of each coating segmentation is by short gradually long, with reach each coating segmentation to leach light relatively even.
The present embodiment adopts fibre core 6 diameter 10um, interior glass-clad 5 diameter 125um, and the silica fiber of surrounding layer 4 diameter 250um, divest protective layer 3 and surrounding layer 4, forms the nuditing fiber of 10cm.With reference to figure 4, the glass dust of selecting refractive index to be more than or equal to the glass inner cladding refractive index, as filter, is divided into coating segmentation 1, coating segmentation 2 13, coating segmentation 3 14, coating segmentation 4 15, coating segmentation 5 16, totally 5 coating segmentations, uniformly-spaced 0.5cm applies, and according to aforementioned exponential formula, the coating interval is made as 1cm, apply length by optimization, making Length Ratio is 0.15:0.2:0.3:0.55:0.9.Experiment shows to leach the cladding light more than 99%, and the cladding light amount of leaching analog computation result as shown in Figure 6.
Claims (4)
1. a cladding light filtering structure; comprise and divested protective layer (3), surrounding layer (4); the optical fiber (2) of exposed one section glass-clad (5) and filter (1) coating on this glass-clad (5); it is characterized in that the refractive index of the refractive index of described filter (1) higher than the described surrounding layer of described optical fiber (2) (4), the coating of described filter (1) is the coating of more than one filters and segmentation coating.
2. cladding light filtering structure according to claim 1, it is characterized in that described filter (1) coating is the coating segmentation with same filter segmentation coating, and the interval between each coating segmentation is greater than zero, and the length of each coating segmentation is by short gradually long.
3. cladding light filtering structure according to claim 1, it is characterized in that described filter (1) coating is that the filter different with two or more respectively is coated in the coating segmentation successively, equal zero or be greater than zero in interval between each coating segmentation, the refractive index of the filter of each coating segmentation is by little gradually large.
4. cladding light filtering structure according to claim 1, is characterized in that described optical fiber (2) is single cladded fiber, doubly clad optical fiber or multi-clad.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2013202512274U CN203326346U (en) | 2013-05-10 | 2013-05-10 | Cladding light filtering structure |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2013202512274U CN203326346U (en) | 2013-05-10 | 2013-05-10 | Cladding light filtering structure |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN203326346U true CN203326346U (en) | 2013-12-04 |
Family
ID=49665641
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2013202512274U Expired - Lifetime CN203326346U (en) | 2013-05-10 | 2013-05-10 | Cladding light filtering structure |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN203326346U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103269010A (en) * | 2013-05-10 | 2013-08-28 | 上海飞博激光科技有限公司 | Cladding light filtering structure and manufacturing method thereof |
-
2013
- 2013-05-10 CN CN2013202512274U patent/CN203326346U/en not_active Expired - Lifetime
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103269010A (en) * | 2013-05-10 | 2013-08-28 | 上海飞博激光科技有限公司 | Cladding light filtering structure and manufacturing method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103269010A (en) | Cladding light filtering structure and manufacturing method thereof | |
| JP6748036B2 (en) | Fiber optic device that dissipates heat with high power | |
| CN102116902A (en) | Optic fiber power beam combiner and preparation method thereof | |
| JP2020517997A5 (en) | ||
| CN105068181B (en) | A kind of fiber cladding light filter and its manufacture method | |
| CN107329205A (en) | A kind of rare-earth doped optical fibre | |
| CA2293132A1 (en) | Triple-clad rare-earth doped optical fiber and applications | |
| KR20160040618A (en) | A spatially modulated cladding mode stripper and optical fiber therewith | |
| CN109768459A (en) | A kind of pump light stripper of laser ablation and preparation method thereof | |
| CN101946377A (en) | Optical fiber laser | |
| CN106383379A (en) | High-bandwidth bending insensitive multi-mode fiber | |
| CN106646742A (en) | Tapered fusing cladding power filter | |
| CN104865638A (en) | Method for leaking cladding light in double-clad optical fiber | |
| CN103545704B (en) | Implanted profile pump coupling process | |
| CN104316993B (en) | A kind of big core diameter energy-transmission optic fibre | |
| CN203326346U (en) | Cladding light filtering structure | |
| CN103353678A (en) | Magnetic-control variable optical attenuator based on magnetofluid and core-free optical fiber | |
| CN110429464A (en) | A kind of superpower laser bundling device | |
| CN207216170U (en) | New multimode pump optical fiber combiner | |
| CN203025420U (en) | Optical fiber beam combiner | |
| US10156675B1 (en) | Method and apparatus for the modulation of pump absorption in a clad optical fiber that is used in lasers and amplifiers | |
| CN207318797U (en) | A kind of inner cladding remnant pump light of doubly clad optical fiber divests structure | |
| CN1251366C (en) | Large mode area double-cladding fiber single-mode laser and manufacturing method | |
| CN106646734A (en) | Optical conductive type cladding power filtering device | |
| CN105846294A (en) | Laser capable of monitoring cutting state in real time |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CX01 | Expiry of patent term |
Granted publication date: 20131204 |
|
| CX01 | Expiry of patent term |