CN104332811A - Optical-fiber laser oscillation system - Google Patents

Abstract

The present invention proposes an optical fiber laser oscillation system, comprising: a laser pump module; an optical fiber oscillation module coupled with the laser pump module, the optical fiber oscillation module includes a resonant cavity and a gain fiber; a cladding leaker is arranged in the resonant cavity Middle; the laser output module is connected with the optical fiber oscillation module for outputting laser signals. The system of the invention has higher output power and efficiency, and has higher output beam quality.

Description

Fiber Laser Oscillating System

technical field

The invention relates to the field of fiber laser technology, in particular to a fiber laser oscillation system.

Background technique

With the development of fiber laser technology and the continuous improvement of fiber output capacity, in some specific fields, it is necessary to release the transmission power in the fiber cladding. For example, pump leakage is performed at the gain tail, and in order to improve the output brightness, the power transmitted in the cladding is leaked to obtain a pure fiber core output.

In the high-power application field, the power tolerance of the leaker becomes one of the restrictive factors for the power expansion of the fiber laser. Therefore, while producing a stable laser output, the amount of cladding light generated should be limited, that is, the cladding light that needs to be processed by the cladding leaker should be controlled at a low level.

For the fiber laser oscillation system, the cladding light mainly comes from the unabsorbed residual pump and the signal light propagating in the fiber core enters the cladding due to the local destruction of the core confinement ability, welding quality and other factors. For residual pumping, there is currently no obvious and effective technical means for the established fiber laser system (system operating wavelength, fiber length, cost, etc.).

Contents of the invention

The present invention aims to solve one of the technical problems in the related art at least to a certain extent.

Therefore, the object of the present invention is to propose a fiber laser oscillation system with simple structure and high efficiency.

In order to achieve the above object, the fiber laser oscillation system of the embodiment of the present invention includes: a laser pump module; a fiber oscillation module coupled with the laser pump module, the fiber oscillation module includes a resonator and a gain fiber; cladding leakage device, the cladding leaker is arranged in the resonant cavity; a laser output module, the laser output module is connected with the optical fiber oscillation module for outputting laser signals.

According to the fiber laser oscillation system of the embodiment of the present invention, through the fiber oscillation module, the high-order mode of the cladding light generated in the system leaks to the fiber cladding, thereby diverging into the environment, while controlling the energy of the cladding light, increasing the The effective power of the fiber laser oscillation system is improved, and the beam quality of the fiber laser system is optimized.

In some examples, the resonator includes an all-fiber resonator and a discrete resonator.

In some examples, the all-fiber resonator includes a first fiber Bragg grating and a second fiber Bragg grating, the gain fiber is located between the first fiber Bragg grating and the second fiber Bragg grating, the first fiber Bragg grating and the second fiber Bragg grating are coupled to the laser pumping module, and the second fiber grating is connected to the laser output module.

In some examples, the all-fiber resonator includes a first fiber grating and a second fiber grating, the first fiber grating is coupled to the laser pumping module, and the second fiber grating is coupled to the fiber transmission module connected.

In some examples, a gain fiber is located between the first fiber Bragg grating and the second fiber Bragg grating.

In some examples, the cladding leaker is disposed on a welding point of the gain fiber and the second fiber grating.

In some examples, the cladding leaker is disposed on the gain fiber within a first predetermined distance adjacent to the solder joint.

In some examples, the cladding leaker is disposed on the input fiber of the second fiber grating.

In some examples, the cladding leaker is disposed on the gain fiber within a second preset distance adjacent to the rear cavity mirror.

In some examples, the discrete resonant cavity includes a front cavity mirror and a rear cavity mirror, the front cavity mirror is adjacent to the laser pumping module, and the rear cavity mirror is adjacent to the laser output module.

In some examples, the laser pumping module is coupled to the optical fiber oscillation module in a side-pump or end-pump manner.

In some examples, the laser pumping module is coupled to the optical fiber oscillation module in a side-pump or end-pump manner.

Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.

Description of drawings

Fig. 1 is a structural block diagram of a fiber laser oscillation system according to an embodiment of the present invention;

Fig. 2 is the structural representation of the fiber laser oscillation system of an embodiment of the present invention; With

Fig. 3 is the structural representation of the traditional fiber laser oscillation system of an embodiment of the present invention

Detailed ways

Embodiments of the present invention are described in detail below, examples of which are shown in the drawings, wherein the same or similar reference numerals designate the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the figures are exemplary and are intended to explain the present invention and should not be construed as limiting the present invention.

Fig. 1 is a structural block diagram of a fiber laser oscillation system according to an embodiment of the present invention. As shown in FIG. 1 , the fiber laser oscillation system of the embodiment of the present invention includes: a laser pump module 100 , a fiber oscillation module 200 coupled with the laser pump module 100 , a cladding leaker 300 and a laser output module 400 .

Wherein, the laser pumping module 100 is coupled with the optical fiber oscillation module 200 by means of a side pump or an end pump. The coupling process can be completed by optical fiber fusion or coupling of discrete components. The fiber oscillation module 200 includes a resonant cavity 201 and a gain fiber 202 . The cladding leaker 300 is disposed in the resonant cavity 201 . The laser output module 400 is connected to the fiber oscillation module 200 for outputting laser signals. Specifically, in an embodiment of the present invention, the resonant cavity 210 includes an all-fiber resonant cavity and a discrete resonant cavity.

Further, in one embodiment of the present invention, the all-fiber resonator includes a first fiber grating and a second fiber grating, the first fiber grating is coupled to the laser pump module 100, and the second fiber grating is connected to the laser output module 400 .

Further, in one embodiment of the present invention, the gain fiber 202 is located between the first fiber Bragg grating and the second fiber Bragg grating.

In one embodiment of the present invention, the cladding leaker 300 can be arranged on the welding point of the gain fiber 202 and the second fiber grating, or can be arranged on the gain fiber within the first preset distance adjacent to the welding point superior. Wherein, in an embodiment of the present invention, the first preset distance is 1 m. The cladding leaker 300 can also be arranged on the input fiber of the second fiber grating.

In addition, in an embodiment of the present invention, the discrete resonant cavity includes a front cavity mirror and a rear cavity mirror, wherein the front cavity mirror is adjacent to the laser pumping module 100 , and the rear cavity mirror is adjacent to the laser output module 400 .

Further, in an embodiment of the present invention, the cladding leaker 300 may be disposed on the gain fiber 202 within a second preset distance adjacent to the rear cavity mirror. Wherein, in an embodiment of the present invention, the second preset distance is 1 m.

As a specific example, as shown in FIG. 2 , the laser pumping module 100 is composed of several laser diodes output with pigtails and coupled into the fiber oscillation module 200 through a multimode fiber combiner. The resonant cavity 201 includes a first fiber Bragg grating A (high reflection) and a second fiber Bragg grating B (output). The gain fiber 202 is located between the first fiber Bragg grating A and the second fiber Bragg grating B, the first fiber Bragg grating A is coupled to the laser pumping module 100 , and the second fiber Bragg grating B is connected to the fiber transmission module 400 . Wherein, the optical fiber transmission module includes a transmission optical fiber 401 and an output end cap 402 . The cladding leaker 400 is an optical leaker that acts on the optical fiber cladding by a certain process, and in the embodiment of the present invention, a refractive index matching method is adopted. By arranging the refractive index matching material 500 with a higher refractive index around the fiber cladding, the purpose of diverging the light in the fiber cladding to the environment is achieved. The cladding leaker 300 is wrapped on the welding point of the gain fiber 202 and the second fiber grating B. In this way, the welding spot is used to strengthen the disturbance of the high-order mode, so that a part of the critically propagated high-order mode enters the cladding when passing through the leaker, forcing it to propagate from the fiber core to the fiber cladding. However, the low-order mode passing through the cladding leaker is not sensitive to subsequent welding points, bending, etc., and can be restricted to continue propagating in the fiber core. In addition, in order to strengthen this disturbance, while the cladding leaker 300 is arranged, the optical fiber at this position is bent with a certain curvature.

In order to further illustrate the advantages of the system of the embodiment of the present invention, a comparison will be made with a traditional fiber laser oscillation system with cladding light leakage capability, as shown in FIG. 3 . The system includes a laser pumping module 10, a first fiber grating (high reflection) a, a gain fiber 22, a cladding leaker 30, a second fiber grating (output) b, and a transmission fiber 41 and an output end cap 42. Fiber optic transport module.

The laser pump module 10 is coupled into the fiber oscillation module (first fiber grating (high reflection) a, gain fiber 22, fiber grating (output) b) by several laser diodes with pigtail output through a multimode fiber combiner. The cladding leaker 30 is an optical leaker that acts on the cladding of the optical fiber by a certain process, adopts a refractive index matching method, and arranges a refractive index matching material 50 with a higher refractive index around the cladding of the optical fiber to achieve The purpose of diverging the light into the environment. The cladding leaker is placed on the transmission fiber 41 .

Compare the fiber laser oscillation system of the embodiment of the present invention (FIG. 2) with the traditional cladding leaky fiber laser system (FIG. 3). In the case of the same injection pumping, fiber length and other conditions, the advantages are: the system of the embodiment of the present invention has higher output power and efficiency, higher output beam quality, and lower operating power of the cladding leaker.

According to the fiber laser oscillation system of the embodiment of the present invention, through the fiber oscillation module, the high-order mode of the cladding light generated in the system leaks to the fiber cladding, thereby diverging into the environment, while controlling the energy of the cladding light, increasing the The effective power of the fiber laser oscillation system is improved, and the beam quality of the fiber laser system is optimized.

In the description of this specification, descriptions referring to the terms "one embodiment", "some embodiments", "example", "specific examples", or "some examples" mean that specific features described in connection with the embodiment or example , structure, material or characteristic is included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the described specific features, structures, materials or characteristics may be combined in any suitable manner in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine different embodiments or examples and features of different embodiments or examples described in this specification without conflicting with each other.

Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention, those skilled in the art can make the above-mentioned The embodiments are subject to changes, modifications, substitutions and variations.

Claims (10)

1. an optical-fiber laser oscillatory system, is characterized in that, comprising:

Pump laser module;

The fiber oscillator module be coupled with described pump laser module, described fiber oscillator module comprises resonant cavity and gain fibre;

Covering Leak artifact, described covering Leak artifact is arranged in described resonant cavity;

Laser output module, described Laser output module is connected with described fiber oscillator module, for Output of laser signal.

2. system according to claim 1, is characterized in that, described resonant cavity comprises all-fiber formula resonant cavity and discrete resonant cavity.

3. system according to claim 2, it is characterized in that, described all-fiber formula resonant cavity comprises the first fiber grating and the second fiber grating, and described first fiber grating is coupled with described pump laser module, and described second fiber grating is connected with described Laser output block.

4. the system according to claim 1 or 3 any one, is characterized in that, described gain fibre is between described first fiber grating and described second fiber grating.

5. the system according to claim 3 or 4 any one, is characterized in that, described covering Leak artifact is arranged on the pad of described gain fibre and described second fiber grating.

6. the system according to claim 3 or 5 any one, is characterized in that, described covering Leak artifact is arranged on the gain fibre within the first predeterminable range adjacent with described pad.

7. system according to claim 3, is characterized in that, described covering Leak artifact is arranged on the input optical fibre of the second fiber grating.

8. system according to claim 2, is characterized in that, described discrete resonant cavity comprises front cavity mirror and Effect of Back-Cavity Mirror, and described front cavity mirror is adjacent with described pump laser module, and described Effect of Back-Cavity Mirror is adjacent with described Laser output module.

9. system according to claim 8, is characterized in that, described covering Leak artifact is arranged on the gain fibre within the second predeterminable range adjacent with described Effect of Back-Cavity Mirror.

10. system according to claim 1, is characterized in that, described pump laser module is coupled with described fiber oscillator module by the mode of side pump or end pump.