CN103018911B - Optical fiber laser synthesizer based on wavelength division multiplexing - Google Patents

Abstract

The present invention proposes a fiber laser synthesis device based on wavelength division multiplexing, including: a plurality of optical filters of different transmission bands, used to transmit lasers of specific bands; a plurality of mirrors, used to change the direction of the synthesized laser light, wherein , a plurality of filters of different transmission bands reflect or transmit multiple lasers of different bands to synthesize multiple primary synthesis modules and generate primary synthesis light, and two primary synthesis modules synthesize an advanced synthesis module, and the generated advanced synthesis light is used as The sub-synthesized light of a higher level is further synthesized with the advanced synthetic light of other wavelength bands. According to the fiber laser synthesis device based on wavelength division multiplexing according to the embodiment of the present invention, the laser light of a specific wave band is transmitted through filters of different transmission wave bands, while the rest of the laser light is reflected, which effectively reduces the number of reflections and reduces the reflection frequency. loss, thereby increasing the power of the synthesized laser under the same conditions.

Description

Optical fiber laser synthesis device based on wavelength division multiplexing

technical field

The invention relates to the field of fiber laser technology, in particular to a fiber laser synthesis device based on wavelength division multiplexing.

Background technique

High-energy and high-power fiber lasers and fiber amplifiers have broad application prospects in industrial processing, medical and health care, and national defense and military affairs due to their advantages such as good beam quality, high efficiency, long life, and compact structure. With the expansion of application fields, higher requirements are placed on the power of fiber lasers. In order to realize the power expansion of the fiber laser, in addition to designing a better internal structure of the laser, it can also be achieved by combining multiple fiber lasers.

Currently commonly used fiber laser combining technologies are mainly divided into coherent combining and incoherent combining. Coherent combining is to phase-lock multiple lasers with the same wavelength and superimpose them in the far field. This method has strict requirements on laser parameters, and the beam quality is poor and susceptible to interference. Incoherent combination includes spectrum combination and adaptive optics combination. Among them, adaptive optics combination focuses the light spots to the same point and then superimposes them directly. The beam quality obtained by this method is poor and the optical system is complex. Spectrum synthesis is to use the principle of wavelength division multiplexing to synthesize multiple lasers with different wavelengths using interference filters or gratings. However, the cost of gratings is high and the number of channels that can be synthesized is limited. In addition, the scalability of multi-channel fiber laser beam combining through the cascading of interference filters in free space is better, but the traditional cascading method increases with the increase in the number of channels The number of reflections on the filter is more, and the reflection loss is larger. Due to the increase in the number of reflections of the single-path light, the overall synthesis efficiency is reduced, and the power loss of the laser after synthesis is large.

Contents of the invention

The object of the present invention is to solve at least one of the above-mentioned technical drawbacks.

In order to achieve the above object, an embodiment of the present invention proposes a fiber laser synthesis device based on wavelength division multiplexing, including: a plurality of optical filters with different transmission bands, used to transmit lasers of specific bands; a plurality of reflectors , used to change the direction of the synthesized laser light, wherein the filters of the multiple different transmission bands reflect or transmit the laser beams of multiple different bands to synthesize multiple primary synthesized modules and generate primary synthesized light, two of the primary synthesized The module synthesizes an advanced synthesis module, and the generated advanced synthetic light is further synthesized as a higher-level sub-synthetic light with advanced synthetic light of other bands.

According to the fiber laser synthesis device based on wavelength division multiplexing according to the embodiment of the present invention, the laser light of a specific wave band is transmitted through filters of different transmission wave bands, while the rest of the laser light is reflected, which effectively reduces the number of reflections and reduces the reflection frequency. loss, thereby increasing the power of the synthesized laser under the same conditions.

In one embodiment of the present invention, the optical filter and the optical path form an appropriate angle between the reflector and the optical path, so that the optical paths of the combined laser beams can overlap when they emerge from the last optical filter.

In one embodiment of the present invention, the primary filter may be a narrow-band interference filter, a long-wave pass filter, or a short-wave pass filter.

In one embodiment of the present invention, the advanced optical filter is a band-pass interference filter, a long-wave pass filter or a short-wave pass filter.

In one embodiment of the present invention, the primary synthesis module includes a primary optical filter, and the advanced synthesis module includes an advanced optical filter, wherein the transmission wavelength band of the advanced optical filter should include all wavelength bands of one channel of synthesized light, All wavelength bands of the other synthetic light are not included.

In one embodiment of the present invention, the primary synthesis module includes a primary filter, and the advanced synthesis module includes a high-level filter, wherein, the filter is configured according to the arrangement of the primary filter for an appropriate combined primary filter. The sub-synthesized light beams are combined.

In one embodiment of the present invention, the optical filter is an optical filter resistant to high power and high energy laser.

In an embodiment of the present invention, the reflective mirror has a relatively high reflectivity for the fiber laser in the wavelength band to be synthesized.

In one embodiment of the present invention, the fiber laser is generated by a high-power ytterbium-doped fiber laser, and the wavelength range is between 1000nm and 1200nm.

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

The above and/or additional aspects and advantages of the present invention will become apparent and easy to understand from the following description of the embodiments in conjunction with the accompanying drawings, wherein:

Fig. 1 is a schematic diagram of a fiber laser synthesis device based on wavelength division multiplexing according to an embodiment of the present invention;

Fig. 2 is a diagram of a specific example of a fiber laser combining device based on wavelength division multiplexing according to an embodiment of the present invention. In Fig. 2, 1 is an advanced synthesis module, 11 is a primary synthesis module, 111 is a fiber laser with a wavelength of 1040nm, 112 is a fiber laser with a wavelength of 1045nm, 113 is a fiber laser with a wavelength of 1050nm, and 114 is a transmission center wavelength of 1045nm 115 is a narrow-band interference filter with a transmission center wavelength of 1050nm, 12 is a primary synthesis module, 121 is a fiber laser with a wavelength of 1055nm, 122 is a fiber laser with a wavelength of 1060nm, and 123 is a wavelength of 1065nm 124 is a narrow-band interference filter with a transmission center wavelength of 1060nm, 125 is a narrow-band interference filter with a transmission center wavelength of 1065nm, 13 is a band-pass filter with a transmission wavelength of 1040nm~1065nm, 2 is an advanced Synthesis module, 21 is primary synthesis module, 211 is a fiber laser with a wavelength of 1070nm, 212 is a fiber laser with a wavelength of 1075nm, 213 is a fiber laser with a wavelength of 1080nm, 214 is a narrow-band interference filter with a transmission center wavelength of 1075nm, 215 is a narrow-band interference filter with a transmission center wavelength of 1080nm, 22 is a primary synthesis module, 221 is a fiber laser with a wavelength of 1085nm, 222 is a fiber laser with a wavelength of 1090nm, 223 is a fiber laser with a wavelength of 1095nm, and 224 is a transmission 225 is a narrow-band interference filter with a transmission center wavelength of 1095nm, 23 is a bandpass filter with a transmission wavelength of 1070nm~1095nm, 3 is a bandpass filter with a transmission wavelength of 1040~1095nm Pass filter, 4 and 5 are mirrors.

Fig. 3 is an example diagram of a fiber laser combining device based on wavelength division multiplexing according to another embodiment of the present invention. In Fig. 3, 4 and 5 are mirrors, 6 is an advanced synthesis module, 61 is a primary synthesis module, 611 is a fiber laser with a wavelength of 1040nm, 612 is a fiber laser with a wavelength of 1045nm, and 613 is a fiber laser with a wavelength of 1050nm. 614 is a long-wave pass filter with a transmission cut-off wavelength of 1045nm, 615 is a long-wave pass filter with a transmission cut-off wavelength of 1050nm, 62 is a primary synthesis module, 621 is a fiber laser with a wavelength of 1055nm, and 622 is a fiber laser with a wavelength of 1060nm , 623 is a fiber laser with a wavelength of 1065nm, 624 is a long-wave pass filter with a transmission cut-off wavelength of 1060nm, 625 is a long-wave pass filter with a transmission cut-off wavelength of 1065nm, and 63 is a long-wave pass filter with a transmission cut-off wavelength of 1052nm 7 is an advanced synthesis module, 71 is a primary synthesis module, 711 is a fiber laser with a wavelength of 1070nm, 712 is a fiber laser with a wavelength of 1075nm, 713 is a fiber laser with a wavelength of 1080nm, and 714 is a long-wave transmission with a cut-off wavelength of 1075nm Pass filter, 715 is a long-wave pass filter with a transmission cut-off wavelength of 1080nm, 72 is a primary synthesis module, 721 is a fiber laser with a wavelength of 1085nm, 722 is a fiber laser with a wavelength of 1090nm, and 723 is a fiber laser with a wavelength of 1095nm , 724 is a long-wave pass filter with a transmission center wavelength of 1090nm, 725 is a long-wave pass filter with a transmission cut-off wavelength of 1095nm, 73 is a long-wave pass filter with a transmission cut-off wavelength of 1082nm, 8 is a transmission cut-off wavelength of 1067nm long wave pass filter.

Detailed ways

Embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the drawings, wherein the same or similar reference numerals denote 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 only for explaining the present invention and should not be construed as limiting the present invention.

In the description of the present invention, it should be understood that the terms "first" and "second" are used for description purposes only, and cannot be interpreted as indicating or implying relative importance or implicitly indicating the quantity of indicated technical features. Thus, a feature defined as "first" and "second" may explicitly or implicitly include one or more of these features. In the description of the present invention, "plurality" means two or more, unless otherwise specifically defined.

Example 1:

Fig. 1 is a schematic flow diagram of using a narrow-band interference filter and a band-pass filter in a fiber laser combining device based on wavelength division multiplexing according to an embodiment of the present invention. Fig. 2 is a specific example diagram of a wavelength division multiplexing-based fiber laser combining device according to another embodiment of the present invention. In the figure, the black cylinders are filters with different transmission bands, and the arrows are lasers.

As shown in Figure 1, the optical fiber laser synthesis device based on wavelength division multiplexing according to the embodiment of the present invention includes a plurality of optical filters of different transmission bands and a plurality of reflection mirrors, wherein the optical filters of a plurality of different transmission bands reflect Or transmit multiple lasers of different wavelengths to synthesize multiple primary synthesis modules and generate primary synthesis light. Two primary synthesis modules synthesize an advanced synthesis module, and the generated advanced synthesis light is used as a higher-level sub-synthesis light to combine with other bands The Advanced Synthetic Light is further synthesized.

Specifically, a plurality of optical filters of different transmission bands are used to transmit laser light of a specific band.

Multiple mirrors to redirect the combined laser light.

In one embodiment of the present invention, the primary synthesis module is composed of two optical filters, and the primary synthetic light is synthesized through the transmission and reflection of the four beams of light by two optical filters with different transmission wavelength bands.

In an embodiment of the present invention, the two primary composite lights generated by the primary composite module 1 and the primary composite module 2 are synthesized into advanced composite light through a light filter, and the whole used is an advanced composite module.

As shown in Figure 1 and Figure 2, the angle between each filter and reflector and the optical path is 45 degrees. The laser light 111 is not in the transmission wavelength band of all the filters in the primary combining module 1 , and is reflected by each filter. The laser light 112 is at the transmission center wavelength of the optical filter 114 and is not in the transmission wavelength range of the subsequent optical filter 115 , after passing through the optical filter 114 , it is reflected by the optical filter 115 . The laser light 113 is at the transmission center wavelength of the filter 115 and passes through the filter 115 . The 3-way fiber laser passes through the filter 115 as the output of the primary synthesis module 11 . The same principle, the other three primary synthesis modules are synthesized according to the same principle, and four primary synthetic lights are obtained. The primary synthesized light output by 11 and 12 is synthesized by band-pass filter 13 into one advanced synthesized light. The primary synthesized light output by 21 and 22 is synthesized by band-pass filter 23 into another path of high-level synthesized light. The two paths of high-grade synthetic light are combined by the band-pass filter 3 after the optical paths are bent by the reflectors 4 and 5 to form synthetic light.

In one embodiment of the present invention, if the reflectivity of the reflection band of the filter and the transmittance of the transmission band are both 99%, this structure is used to synthesize 12 fiber lasers (each primary synthesis module synthesizes 3 paths of light), Then the synthesis efficiency is 1.6% higher than that of the cascaded bundle.

In one embodiment of the present invention, the fiber laser is produced by a high-power ytterbium-doped fiber laser with a wave band between 1000nm and 1200nm, and the filter is a band-pass interference filter, a long-wave pass filter or a short-wave pass filter sheet, so that fiber lasers of different wavelength bands can be transmitted.

Example 2:

Fig. 3 is an example diagram of a fiber laser combining device based on wavelength division multiplexing according to another embodiment of the present invention. As shown in FIG. 3 , the included angle between each filter and reflector and the optical path is 45 degrees. The laser light 611 is not in the transmission band of all the filters in the primary synthesis module, and is reflected by each filter, and the laser light 612 is in the transmission band of the filter 614 and not in the transmission wavelength range of the following filters, After passing through 614, it is reflected by the filter 615. The laser 613 is in the transmission band of the filter 615 and passes through 615. After the 3-way fiber laser passes through the filter 615, it is used as the output of the primary synthesis module 61, and the other 3 primary The synthetic lights are combined according to the same principle to obtain four primary synthetic lights. The primary synthesized light output by 61 and 62 is synthesized by the long-wave filter 63 into one advanced synthesized light. The primary synthesized light output by 71 and 72 is synthesized by the long-wave filter 73 into another advanced synthesized light. The two paths of high-grade synthetic light are combined by the long-wave filter 3 after the reflectors 4 and 5 bend the optical path to form synthetic light.

According to the fiber laser synthesis device based on wavelength division multiplexing according to the embodiment of the present invention, the laser light of a specific wave band is transmitted through filters of different transmission wave bands, while the rest of the laser light is reflected, which effectively reduces the number of reflections and reduces the reflection frequency. loss, thereby increasing the power of the synthesized laser under the same conditions.

Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be construed as limitations to the present invention. Variations, modifications, substitutions, and modifications to the above-described embodiments are possible within the scope of the present invention.

Claims (7)

1. based on an optical fiber laser synthesizer for wavelength-division multiplex, it is characterized in that, comprising:

The optical filter of multiple different transmission wave band, for the laser of transmission specific band;

Two catoptrons, for changing the direction of synthetic laser;

Wherein, the optical filter reflection of described multiple different transmission wave band or the multiple elementary synthesis module of Laser synthesizing of the multiple different-waveband of transmission, and generate elementary synthesis light, two described elementary synthesis modules synthesize a senior synthesis module, two senior synthesis modules generate the more higher leveled sub more higher leveled synthesis light synthesizing light and its all band through described two catoptrons reflection and synthesize further

Described optical filter becomes with light path, described catoptron and light path angle at 45 °, and the light path of each road laser of synthesis is overlapped from during last optical filter outgoing,

Described elementary synthesis module comprises elementary optical filter, and senior synthesis module comprises senior optical filter, and wherein, the transmission wave band of described senior optical filter should comprise all wave bands of a way synthesis light, does not comprise all wave bands of another way synthesis light.

2., as claimed in claim 1 based on the optical fiber laser synthesizer of wavelength-division multiplex, it is characterized in that, described elementary optical filter is spike interference filter, long wave pass filter or short wave pass filter.

3., as claimed in claim 1 or 2 based on the optical fiber laser synthesizer of wavelength-division multiplex, it is characterized in that, described senior optical filter is bandpass interference filter, long wave pass filter or short wave pass filter.

4. as claimed in claim 1 based on the optical fiber laser synthesizer of wavelength-division multiplex, it is characterized in that, described elementary synthesis module comprises elementary optical filter, senior synthesis module comprises senior optical filter, wherein, described optical filter carries out conjunction bundle according to the arrangement of elementary optical filter to the elementary son synthesis light after suitable combination.

5., as claimed in claim 1 based on the optical fiber laser synthesizer of wavelength-division multiplex, it is characterized in that, described optical filter is the optical filter of the high energy laser of resistance to high power.

6., as claimed in claim 1 or 2 based on the optical fiber laser synthesizer of wavelength-division multiplex, it is characterized in that, the optical-fiber laser of described catoptron to the wave band that will synthesize has higher reflectivity.

7., as claimed in claim 1 or 2 based on the optical fiber laser synthesizer of wavelength-division multiplex, it is characterized in that, described optical-fiber laser is produced by high power ytterbium-doping optical fiber laser, and wave band is between 1000nm to 1200nm.