CN115220147A - Cladding light stripper and preparation method thereof - Google Patents

Abstract

The invention discloses a cladding light stripper and a preparation method thereof. The cladding optical stripper includes an optical fiber, and the optical fiber includes a core, an inner cladding layer and a coating layer; the inner cladding layer is wrapped on the outer side of the fiber core, the coating layer is wrapped on the outer side of the inner cladding layer, and the optical fiber has a coating layer that is stripped off The cladding light stripping section, the outer side wall of the inner cladding in the cladding light stripping section is provided with at least one section of the inner cladding texturing section whose total reflection property of the inner cladding transmission interface is destroyed, and the inner cladding texturing section is The interior of the inner cladding is provided with a plurality of inner cladding cavities. The cladding light stripping has the advantages of simple structure, small volume, easy processing, and high cladding light stripping power.

Description

A kind of cladding light stripper and preparation method thereof

technical field

The invention belongs to the technical field of lasers, and particularly relates to a cladding light stripper and a preparation method thereof.

Background technique

During the laser generation process of the fiber laser, the energy transfer between the pump light and the signal light is carried out in the doped fiber, the pump light is weakened, and the signal light is strengthened. Since the pump energy cannot be fully absorbed, there will be residual pump light transmitted in the cladding of the fiber to form cladding light. The cladding light will not only affect the quality of the laser output, but may also cause damage to subsequent devices. Usually, the cladding light in the fiber cladding is stripped by the cladding light stripper. The main function of the cladding light stripper is to strip the cladding light by destroying the total reflection interface between the fiber claddings, thereby eliminating the cladding light. Influence on the laser output beam quality.

At present, by setting a groove with a certain depth in the cladding light stripping section, the cladding light is stripped from the cladding layer by using the scattering formed after the cladding light enters the groove. In order to ensure the stripping efficiency of the cladding light , it is usually necessary to increase the depth of the groove and extend the distribution area of the groove, so that more cladding light can be scattered in contact with the groove, and the peeling effect can be improved, but it will lead to large volume and complicated preparation.

SUMMARY OF THE INVENTION

In view of the above problems, the present invention discloses a cladding light stripper and a preparation method thereof, so as to overcome the above problems or at least partially solve the above problems.

In order to achieve the above object, the present invention adopts the following technical solutions:

One aspect of the present invention provides a cladding optical stripper, the cladding optical stripper includes an optical fiber, and the optical fiber includes a core, an inner cladding layer and a coating layer;

The inner cladding layer is wrapped around the outer side of the core, the coating layer is wrapped around the outer side of the inner cladding layer, the optical fiber has a cladding light stripping section with the coating layer stripped off, and the cladding layer is The outer sidewall of the inner cladding in the light stripping section is provided with at least one section of inner cladding textured section in which the total reflection property of the inner cladding transmission interface is destroyed, and the inner cladding in the inner cladding textured section has an inner cladding textured section. A plurality of inner cladding cavities are opened inside.

Further, the sizes of the plurality of inner cladding cavities are different.

Further, the spacing distances of a plurality of the inner cladding cavities in the axial direction of the inner cladding are not equal.

Further, the coating layer on the light peeling section of the cladding layer is peeled off by a method of thermal peeling, blade peeling or chemical peeling.

Further, the inner cladding textured section is formed by femtosecond laser firing.

Further, the inner cladding cavity is formed by femtosecond laser firing.

Further, the optical fiber also includes an outer cladding;

The outer cladding is located between the inner cladding layer and the coating layer, and at least a section of the outer cladding textured section in which the total reflection property of the outer cladding transmission interface is destroyed is arranged on the outer sidewall of the outer cladding.

Further, a plurality of outer cladding cavities are opened inside the outer cladding in the outer cladding texturing section.

Further, the length of the cladding light stripping section is 5 mm˜50 mm.

Another aspect of the present invention provides a preparation method of a cladding light stripper, the preparation method is used to manufacture the above-mentioned cladding light stripper, comprising the following steps:

Step S01, stripping the coating layer of the optical fiber to form a cladding light stripping section;

Step S02, firing at least one section of inner cladding texturing section on the outer sidewall of the inner cladding in the cladding light stripping section;

Step S03, firing a plurality of inner cladding cavities inside the inner cladding in the inner cladding texturing section.

The advantages and beneficial effects of the present invention are:

In the cladding light stripper of the present invention, at least one section of inner cladding textured section in which the total reflection property of the inner cladding transmission interface is destroyed is arranged on the cladding light stripping section from which the coating layer is stripped, and the inner cladding hair is A plurality of inner cladding cavities are arranged inside the inner cladding in the inner cladding section, so that the cladding light in the inner cladding is scattered through the inner cladding cavity, and then peeled off by the inner cladding texturing section. The light stripping effect is better, and the axial length of the inner cladding textured section is shortened; the cladding light stripping has the advantages of simple structure, small volume, easy processing, and high cladding light stripping power.

Description of drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are for the purpose of illustrating preferred embodiments only and are not to be considered limiting of the invention. Also, the same components are denoted by the same reference numerals throughout the drawings. In the attached image:

1 is a schematic structural diagram of a cladding light stripper in an embodiment of the present invention;

FIG. 2 is an implementation step diagram of a method for preparing a cladding light stripper in another embodiment of the present invention.

In the figure: 1. Core; 2. Inner cladding; 3. Coating layer; 4. Textured section of inner cladding; 5. Inner cladding cavity.

Detailed ways

In order to make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the specific embodiments of the present invention and the corresponding drawings. Obviously, the described embodiments are only some, but not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

The technical solutions provided by the embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

An embodiment of the present invention provides a cladding optical stripper. As shown in FIG. 1 , the cladding optical stripper includes an optical fiber, and the optical fiber includes a core 1 , an inner cladding layer 2 and a coating layer 3 .

Specifically, the inner cladding layer 2 is wrapped around the outer side of the core 1, the coating layer 3 is wrapped around the outer side of the inner cladding layer 2, and the optical fiber has a cladding light stripping section where the coating layer 3 is stripped off, and the cladding light stripping section is There is a section of inner cladding textured section 4 in which the total reflection property of the inner cladding transmission interface is destroyed on the outer side wall of the inner cladding layer 2, and a plurality of inner cladding layers are opened inside the inner cladding layer 2 in the inner cladding textured section 4. cavity 5. In this way, a part of the cladding light transmitted in the inner cladding layer 2, when reflected to the inner cladding texturing section 4, will be emitted through the inner cladding texturing section 4 to realize the stripping of the cladding light; the other part of the inner cladding layer 2 The cladding light transmitted in the middle cladding will be scattered when it hits the inner cladding cavity 5, and the generated scattered light is emitted through the inner cladding texturing section 4 to realize the stripping of the cladding light, thereby making the degree of stripping of the cladding light higher. high. In addition, by disposing the inner cladding cavity, the required length of the inner cladding texturing section 4 in the axial direction can be reduced, thereby making the cladding light stripper smaller in size. In addition, the arrangement of the textured section of the inner cladding and the cavity of the inner cladding does not destroy the overall structure of the inner cladding layer, so that the inner cladding layer still has good mechanical properties. Therefore, the cladding light stripper of this embodiment has the advantages of simple structure, small volume, easy processing, and high cladding light stripping power.

In other embodiments, the outer sidewall of the inner cladding in the cladding light stripping section may also be provided with multi-segment inner cladding textured sections in which the total reflection property of the inner cladding transmission interface is destroyed.

In this embodiment, the sizes of the multiple inner cladding cavities are different, so that the scattering angles of the cladding light in the inner cladding passing through different inner cladding cavities are different, so that the scattering range of the scattered light is larger, thereby facilitating the cladding The scattered light generated by the light is better emitted through the textured area of the inner cladding, so that the peeling effect of the cladding light is better.

In addition, the distances between the plurality of inner cladding cavities in the axial direction of the inner cladding are different, so that the cladding light with different reflection angles in the inner cladding can be scattered and stripped, thereby improving the degree of stripping of the cladding light. Of course, in other embodiments, the spacing distances of the plurality of inner cladding cavities in the axial direction of the inner cladding may be equal, which is also within the protection scope of the present invention.

In this embodiment, the coating layer on the light peeling section of the cladding layer is peeled off by thermal peeling, blade peeling or chemical peeling. Here, it should be noted that when peeling off the coating layer, it is necessary to keep the peeling opening uniform and complete without burrs. In addition, the length of the cladding light stripping section is 5 mm to 50 mm, and the cladding light stripping section of this length can be easily processed while realizing the cladding light stripping.

Further, the textured section of the inner cladding is formed by femtosecond laser firing, and the femtosecond laser can form a uniform textured structure on the outer sidewall of the inner cladding layer, thereby ensuring the overall uniformity of the inner cladding layer. Of course, the textured section of the inner cladding can also be processed by other processing methods, and is not limited to being produced by femtosecond laser firing.

Moreover, the inner cladding cavity is also formed by femtosecond laser firing. Due to the characteristics of the femtosecond laser, it only has the ability to burn at the focus. Specifically, the femtosecond laser can pass through the outer layer of the inner cladding, and the inner The internal firing of the inner cladding cavity, thereby realizing fixed-point firing, to avoid damage to other structures, thereby ensuring the integrity of the overall structure of the inner cladding.

Femtosecond lasers, as a processing technology, have proven to be a powerful tool for advanced materials processing at the micro- and nanoscale. ^{Femtosecond laser} refers to ultra-short pulse laser with extremely narrow pulse width generated by mode-locking technology. It has many unique properties: (1) On the time scale, the ultrashort pulse width of the femtosecond laser limits the formation of the heat-affected zone, which is crucial for ultra-high-precision manufacturing; (2) On the spatial scale, the femtosecond laser The interaction with materials reflects a variety of nonlinear processes, such as nonlinear optical absorption, nonlinear chemical reaction, and nonlinear material modification, etc. With these nonlinear processes, the optical diffraction limit can be broken and nanoscale microstructures can be prepared. (3) In the dimension of the material, the extremely high peak intensity allows the laser to interact nonlinearly with almost any substance, that is, when the femtosecond laser is irradiated on transparent materials such as dielectrics and wide-bandgap crystals, the peak intensity of the laser is extremely high. High, a nonlinear absorption process will occur, resulting in strong light absorption; based on this feature, femtosecond lasers can realize processing and modification inside transparent materials.

In this embodiment, the optical fiber further includes an outer cladding.

Specifically, the outer cladding is located between the inner cladding layer and the coating layer, and the outer sidewall of the outer cladding in the cladding light stripping section is provided with at least one section of the outer cladding textured section in which the total reflection property of the outer cladding transmission interface is destroyed, In this way, the cladding light in the outer cladding can be emitted through the outer cladding texturing section, so as to realize the stripping of the cladding light in the outer cladding. In addition, the cladding light in the inner cladding is injected into the outer cladding through the inner cladding texturing section, and then exits through the outer cladding texturing section, thereby realizing the peeling of the cladding light in the inner cladding. Wherein, the positions of the outer cladding section and the inner cladding section correspond, so that the cladding light in the inner cladding is scattered and peeled through the outer cladding.

In addition, a plurality of outer cladding cavities are opened inside the outer cladding in the outer cladding texturing section. The function principle of the outer cladding cavity is the same as the above-mentioned outer cladding cavity. The setting of the outer cladding cavity can improve the cladding light in the outer cladding degree of peeling.

Further, the outer cladding textured section and the outer cladding cavity are also fired by femtosecond laser, so that the inner cladding and the outer cladding can be fired to form cladding light peeling without destroying the overall structure of the outer cladding. The structure ensures the integrity of the outer cladding structure and makes the mechanical properties of the optical fiber better.

Another aspect of the present invention provides a method for preparing a cladding optical stripper, which is used to manufacture the cladding optical stripper in the above embodiment. As shown in FIG. 2 , the preparation method includes the following steps:

In step S01, the coating layer of the optical fiber is stripped to form a cladding light stripping section, thereby facilitating the fabrication of a cladding light stripping structure on the cladding light stripping section.

Step S02 , setting the exposure power and focusing position of the femtosecond laser, and firing at least one section of inner cladding texturing section on the outer sidewall of the inner cladding in the cladding light stripping section. The exposure power is determined according to the material of the inner cladding layer and the depth of the inner cladding textured section to be fired, and the focus position is determined according to the position of the inner cladding textured section to be fired.

Step S03 , adjusting the exposure power and focusing position of the femtosecond laser, and firing a plurality of inner cladding cavities inside the inner cladding in the inner cladding texturing section.

The preparation method of the cladding light stripper has the advantages of simple operation, high preparation efficiency, and can be used for streamlined production.

The above descriptions are only specific embodiments of the present invention, and those skilled in the art can make other improvements or modifications on the basis of the above embodiments under the above teachings of the present invention. Those skilled in the art should understand that the above-mentioned specific description is only for better explaining the purpose of the present invention, and the protection scope of the present invention should be based on the protection scope of the claims.

Claims (10)

1. A cladding optical stripper, wherein the cladding optical stripper comprises an optical fiber, and the optical fiber comprises a fiber core, an inner cladding layer and a coating layer; The inner cladding layer is wrapped around the outer side of the core, the coating layer is wrapped around the outer side of the inner cladding layer, the optical fiber has a cladding light stripping section with the coating layer stripped off, and the cladding layer is The outer sidewall of the inner cladding in the light stripping section is provided with at least one section of inner cladding textured section in which the total reflection property of the inner cladding transmission interface is destroyed, and the inner cladding in the inner cladding textured section has an inner cladding textured section. A plurality of inner cladding cavities are opened inside. 2 . The cladding light stripper according to claim 1 , wherein a plurality of the inner cladding cavities have different sizes. 3 . 3 . The cladding light stripper according to claim 1 , wherein the spacing distances of the plurality of inner cladding cavities in the axial direction of the inner cladding are unequal. 4 . 4 . The cladding light stripper according to claim 1 , wherein the coating layer on the cladding light stripping section is stripped by thermal stripping, blade stripping or chemical stripping. 5 . 5 . The cladding light stripper of claim 1 , wherein the inner cladding texturized section is formed by femtosecond laser firing. 6 . 6 . The cladding optical stripper according to claim 1 , wherein the inner cladding cavity is formed by femtosecond laser firing. 7 . 7. The cladding optical stripper according to any one of claims 1 to 6, wherein the optical fiber further comprises an outer cladding; The outer cladding is located between the inner cladding layer and the coating layer, and at least a section of the outer cladding textured section in which the total reflection property of the outer cladding transmission interface is destroyed is arranged on the outer sidewall of the outer cladding. 8 . The cladding optical stripper according to claim 7 , wherein a plurality of outer cladding cavities are opened inside the outer cladding in the outer cladding texturing section. 9 . 9 . The cladding light stripper according to claim 1 , wherein the length of the cladding light stripping section is 5 mm˜50 mm. 10 . 10 . A method for preparing a cladding optical stripper, wherein the preparation method is used to manufacture the cladding optical stripper according to any one of claims 1 to 9 , comprising the following steps: Step S01, stripping the coating layer of the optical fiber to form a cladding light stripping section; Step S02, firing at least one section of inner cladding texturing section on the outer sidewall of the inner cladding in the cladding light stripping section; Step S03, firing a plurality of inner cladding cavities inside the inner cladding in the inner cladding texturing section.

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