阅读说明：本技术 一种可实现高效弯曲选模的光纤冷却装置 (Optical fiber cooling device capable of realizing efficient bending and mode selection ) 是由 王岩山 马毅 孙殷宏 王珏 常哲 彭万敬 唐淳 周侨 彭珏 王尧 于 2019-11-04 设计创作，主要内容包括：本发明公开了一种可实现高效弯曲选模的光纤冷却装置,包括光纤和水冷板,所述水冷板上设置光纤槽道；所述光纤槽道为多个弧形槽道两两连接组成的闭合槽道,相邻两个弧形槽道相切并采用圆弧连接；所述光纤槽道内设置容纳光纤的光纤槽,所述光纤槽盘绕在光纤槽道内；所述光纤沿光纤槽道中的光纤槽盘绕于水冷板上。采用本发明的一种可实现高效弯曲选模的光纤冷却装置,能增加高阶模式激光的损耗,实现光纤激光高光束质量输出,具有高紧凑型、高效高阶模滤除、搭建便易性等特点。(The invention discloses an optical fiber cooling device capable of realizing efficient bending and mode selection, which comprises an optical fiber and a water cooling plate, wherein an optical fiber channel is arranged on the water cooling plate; the optical fiber channel is a closed channel formed by connecting a plurality of arc-shaped channels in pairs, and two adjacent arc-shaped channels are tangent and connected by adopting arcs; a fiber groove for accommodating optical fibers is arranged in the fiber channel, and the fiber groove is coiled in the fiber channel; the optical fiber is coiled on the water cooling plate along the optical fiber groove in the optical fiber groove. The optical fiber cooling device capable of realizing efficient bending mode selection can increase the loss of high-order mode laser and realize high-beam quality output of the optical fiber laser, and has the characteristics of high compactness, efficient high-order mode filtering, convenience in building and the like.)

1. The utility model provides a can realize high-efficient crooked optical fiber cooling device who selects the mould, includes optic fibre and water-cooling board, its characterized in that: the water cooling plate is provided with an optical fiber channel;

the optical fiber channel is a closed channel formed by connecting a plurality of arc-shaped channels in pairs, and two adjacent arc-shaped channels are tangent and connected by adopting arcs;

a fiber groove for accommodating optical fibers is arranged in the fiber channel, and the fiber groove is coiled in the fiber channel;

the optical fiber is coiled on the water cooling plate along the optical fiber groove in the optical fiber groove.

2. The apparatus for cooling an optical fiber capable of achieving efficient bend mode selection according to claim 1, wherein: the optical fiber groove is characterized by further comprising an input optical fiber groove and an output optical fiber groove, wherein the input optical fiber groove and the output optical fiber groove are respectively connected with two ends of the optical fiber groove.

3. The apparatus for cooling an optical fiber capable of achieving efficient bend mode selection according to claim 2, wherein: the cross sections of the input optical fiber channel, the output optical fiber channel and the optical fiber channel are U-shaped grooves, V-shaped grooves or rectangular grooves.

4. The apparatus for cooling an optical fiber capable of achieving efficient bend mode selection according to claim 2, wherein: the input optical fiber channel and the output optical fiber channel are tangent to the optical fiber channel.

5. The apparatus for cooling an optical fiber capable of achieving efficient bend mode selection according to claim 2, wherein: the coiling structure of the optical fiber groove in the optical fiber groove is as follows: starting from a connection point of an input optical fiber channel (or an output optical fiber channel) and the optical fiber channel, winding a first circle of optical fiber grooves along the optical fiber channel, then winding the optical fiber grooves from an outer circle to an inner circle (or from the inner circle to the outer circle) to form a 1 st circle and a 2 nd circle of optical fiber grooves which are wound from outside to inside (or from inside to outside), wherein the distance between every two adjacent circles of optical fiber grooves is equal;

the length of the first circle of optical fiber grooves is L, the distance between two adjacent circles of optical fiber grooves is D, D is not less than the diameter of the optical fiber coating layer, the length of the optical fiber groove from any point on the first circle of optical fiber grooves to the connection point of the input optical fiber channel (or the output optical fiber channel) and the optical fiber channel is X, and the distance D' between any point of the first circle of optical fiber grooves and the edge of the adjacent optical fiber channel is D (X/L).

6. The apparatus for cooling an optical fiber capable of achieving efficient bend mode selection according to claim 1, wherein: the plurality of arc-shaped channels constituting the optical fiber channel have different radii of curvature.

7. The apparatus for cooling an optical fiber capable of achieving efficient bend mode selection according to claim 1, wherein: the difference between the maximum curvature radius and the minimum curvature radius of the arc-shaped grooves in the same circle of optical fiber grooves is less than or equal to 40 percent.

8. The apparatus for cooling an optical fiber capable of achieving efficient bend mode selection according to claim 1, wherein: the minimum curvature radius of the arc-shaped channel is more than or equal to 1.5 cm.

9. The apparatus for cooling an optical fiber capable of achieving efficient bend mode selection according to claim 2, wherein: the length of the input optical fiber channel and the output optical fiber channel is 5-20cm, and the total length of the optical fiber groove is 3-50 m.

10. The apparatus for cooling an optical fiber capable of achieving efficient bend mode selection according to claim 1, wherein: the centers of circles of the arc-shaped channels are located on a plurality of straight lines, and all the straight lines where the centers of circles are located form a polygon.

Technical Field

The invention relates to an optical fiber cooling device capable of realizing efficient bending mode selection, and belongs to the technical field of laser optical fiber cooling.

Background

The fiber laser has the advantages of high electro-optic conversion efficiency, good output beam quality, convenience in heat management, stability in working operation and the like, and is a hotspot studied by researchers in recent years. Since 2000, the power of fiber lasers has been rapidly developed, and the quality of output laser beams is more and more required while the power is improved.

At present, the high-power fiber laser mainly has two structures, one is an oscillation structure based on fiber bragg grating, and the other is a one-stage or multi-stage power amplification structure of a low-power seed source. The optical fiber lasers with two structures can use the large mode field optical fiber in order to realize high power output, and the large mode field optical fiber can bring about two problems: on the one hand, the large mode field optical fiber has a plurality of modes, and mode coupling can lead to the light beam quality to be deteriorated, and on the other hand, after the power of the optical fiber laser adopting the large mode field optical fiber reaches a certain threshold value, high heat load can lead to mode instability effect in the optical fiber laser system, and further lead to the light beam quality to be deteriorated. In order to further improve the output power of the fiber laser and achieve excellent beam quality performance, the number of modes of the laser needs to be strictly controlled. The loss of high-order modes can be obviously increased by bending the large-mode-field optical fiber to a proper size, and the quality of the light beam output by the laser can be greatly improved.

The existing optical fiber cooling devices mostly adopt a cylindrical coiling cooling (such as CN201210362883.1) or a cooling plate to cool the optical fiber in a circular (such as CN201010205769.9) or runway type (such as CN107153241A) coiling manner and can play a certain bending mode selection role at the same time, but the devices have the following disadvantages: (1) although the cylindrical coiling cooling method can realize better bending mode selection effect, the volume is larger, and the cylindrical coiling cooling method is inconvenient for the integrated integration of optical fibers and other devices such as a signal pumping power beam combiner, a pumping power stripper and the like because the cylindrical coiling cooling method is cylindrical; (2) the circular coiling mode is not beneficial to the bending mode selection of the rear-end optical fiber because the radius of the outer ring of the optical fiber is sharply increased along with the increase of the length of the optical fiber; (3) the runway type winding mode has a straight channel, so that the optical fiber cannot be bent and selected effectively.

Disclosure of Invention

The invention aims to: aiming at the existing problems, the invention provides the optical fiber cooling device capable of realizing efficient bending mode selection, and the invention can effectively bend and filter high-order modes of all optical fibers to improve the beam quality of the optical fiber laser.

The technical scheme adopted by the invention is as follows:

an optical fiber cooling device capable of realizing efficient bending mode selection comprises an optical fiber and a water cooling plate, wherein an optical fiber channel is arranged on the water cooling plate;

the optical fiber channel is a closed channel formed by connecting a plurality of arc-shaped channels in pairs, and two adjacent arc-shaped channels are tangent and connected by adopting arcs;

a fiber groove for accommodating optical fibers is arranged in the fiber channel, and the fiber groove is coiled in the fiber channel;

the optical fiber is coiled on the water cooling plate along the optical fiber groove in the optical fiber groove.

In the above scheme, the arc connection means that the arc smoothly connects the arc or the straight line; the optical fiber is disposed in the optical fiber groove, and is wound in the optical fiber groove, and the optical fiber groove bends the optical fiber with a certain curvature radius.

Preferably, the optical fiber groove connector further comprises an input optical fiber groove and an output optical fiber groove, wherein the input optical fiber groove and the output optical fiber groove are respectively connected with two ends of the optical fiber groove.

Preferably, the cross sections of the input optical fiber channel, the output optical fiber channel and the optical fiber groove are U-shaped grooves, V-shaped grooves or rectangular grooves.

Preferably, the input fiber channel and the output fiber channel are both tangent to the fiber channel.

Preferably, the input fiber channel and the output fiber channel are oriented in the same direction as the direction of the connected fiber grooves.

Preferably, the input optical fiber channel and the output optical fiber channel do not intersect with the optical fiber channel except for the connection point with the optical fiber channel.

Preferably, the optical fiber grooves are of a winding structure formed by connecting a plurality of arc-shaped grooves in pairs, and the optical fiber grooves are wound along the optical fiber groove channels.

Preferably, the difference between the curvature radiuses of the adjacent circles of the optical fiber grooves is not less than the diameter of the optical fiber coating layer.

Preferably, the winding structure of the optical fiber groove in the optical fiber groove is as follows: starting from a connection point of an input optical fiber channel (or an output optical fiber channel) and the optical fiber channel, winding a first circle of optical fiber grooves along the optical fiber channel, then winding the optical fiber grooves from an outer circle to an inner circle (or from the inner circle to the outer circle) to form a 1 st circle and a 2 nd circle of optical fiber grooves which are wound from outside to inside (or from inside to outside), wherein the distance between every two adjacent circles of optical fiber grooves is equal;

the length of the first circle of optical fiber grooves is L, the distance between every two adjacent circles of optical fiber grooves is D, D is not smaller than the diameter of an optical fiber coating layer, the length of the optical fiber groove, which is away from the connection point of an input optical fiber channel (or an output optical fiber channel) and the optical fiber channel, of any point on the first circle of optical fiber grooves is X, the distance D' between any point of the first circle of optical fiber grooves and the edge of the adjacent optical fiber channel is D (X/L), and the distance between the first circle of optical fiber channels and the edge of the adjacent optical fiber channel is D when the optical fiber grooves are coiled to the place where the input optical fiber channel (or the output optical fiber channel.

Preferably, the plurality of arc-shaped channels constituting the optical fiber channel have the same radius of curvature.

Preferably, the plurality of arc-shaped channels constituting the optical fiber channel have different radii of curvature.

Preferably, the difference between the maximum curvature radius and the minimum curvature radius of the arc-shaped grooves in the same circle of optical fiber grooves is less than or equal to 40 percent.

Preferably, the minimum curvature radius of the arc-shaped channel is more than or equal to 1.5 cm.

Preferably, the length of the input fiber channel and the output fiber channel is 5-20cm, and the total length of the fiber groove is 3-50 m.

Preferably, the centers of the arc-shaped channels are located on a plurality of straight lines, and all the straight lines where the centers of the circles are located form a polygon.

Preferably, the fusion splice points are disposed in the input fiber channel and the output fiber channel.

Preferably, the optical fiber and the optical fiber fusion-splicing point are fixed in the optical fiber channel, the input optical fiber channel and the output optical fiber channel by an adhesive.

Preferably, a water channel is arranged in the water cooling plate, a water inlet and a water outlet are arranged on the water cooling plate, the water inlet is located at one end of the water channel, and the water outlet is arranged at the other end of the water channel.

Preferably, the water cooling plate is provided with a fixing hole.

Preferably, the adhesive is a heat-conducting glue or a heat-conducting silicone grease.

The design method of the optical fiber channel comprises the following steps:

step a: making a polygon;

step b: making a plurality of circles with the centers positioned on the side lines of the polygon, wherein two adjacent circles are tangent;

step c: and removing redundant arc sections, and connecting all tangent arc sections by adopting arcs to form a closed optical fiber channel basic track.

Wherein, the two adjacent circles refer to two circles with adjacent circle centers on the same sideline, and when the circle centers are not at the sideline intersection point, the two circles closest to the intersection point on the two sidelines are referred to; when the center of only one circle is located on one side line, the circle and the circle with the center located on the adjacent side line and the nearest distance to the intersection point of the two side lines are indicated.

In summary, due to the adoption of the technical scheme, the invention has the beneficial effects that:

1. all the optical fibers are arranged in the arc-shaped optical fiber channel with a certain curvature radius, so that the loss of high-order mode laser can be increased, and the high-beam quality output of the optical fiber laser is realized;

2. the length of the arc-shaped groove for arranging the optical fiber and the difference between the curvature radius of the minimum arc-shaped groove and the curvature radius of the maximum arc-shaped groove are controlled by controlling the number and the curvature radius of the same circle of arc-shaped grooves and the distance between two adjacent circles of arc-shaped grooves, so that the optical fibers with different lengths are bent, selected and cooled;

3. the two fusion points of the optical fiber are respectively placed in the linear optical fiber channel, so that the fusion points are prevented from being positioned in the arc optical fiber channel, and the fusion points are prevented from being broken due to stress;

4. by controlling the coiling mode of the arc-shaped channel for arranging the optical fiber, the occupied area of the optical fiber channel in a cold plate, the length of the optical fiber channel, the maximum curvature radius of the arc-shaped optical fiber channel and the difference between the maximum curvature radius and the minimum curvature radius can be effectively controlled;

5. the method has the characteristics of high compactness, high efficiency, high-order mode filtering, convenience in construction and the like.

Drawings

The invention will now be described, by way of example, with reference to the accompanying drawings, in which:

FIG. 1 is a schematic view of a first fiber channel configuration;

FIG. 2 is a diagram of a first fiber channel design;

FIG. 3 is a schematic view of a first optical fiber cooling device;

FIG. 4 is a schematic view of a second fiber channel configuration;

FIG. 5 is a second fiber channel design;

FIG. 6 is a schematic view of a second optical fiber cooling device;

FIG. 7 is a schematic view of a third fiber channel configuration;

FIG. 8 is a third fiber channel design;

FIG. 9 is a schematic view of a third optical fiber cooling device;

FIG. 10 is a schematic view of a fourth fiber channel configuration;

FIG. 11 is a fourth fiber channel design;

FIG. 12 is a schematic view of a fourth optical fiber cooling device; .

The labels in the figure are: 1-optical fiber channel, 2-input optical fiber channel, 3-output optical fiber channel, 4-optical fiber channel, 5-cooling plate, 6-water channel, 7-water inlet, 8-water outlet and 9-fixing hole.

Detailed Description

All of the features disclosed in this specification, or all of the steps in any method or process so disclosed, may be combined in any combination, except combinations of features and/or steps that are mutually exclusive.

Any feature disclosed in this specification may be replaced by alternative features serving equivalent or similar purposes, unless expressly stated otherwise. That is, unless expressly stated otherwise, each feature is only an example of a generic series of equivalent or similar features.