Pulse / continuous integrated fiber laser

Abstract

The invention relates to a pulse / continuous integrated fiber laser, and relates to the technical field of fiber lasers. Comprising a pulse laser module, a continuous laser module, a laser amplification module and a laser electric control system which are welded in sequence. The pulse laser module is used for generating a pulse laser seed; the continuous laser module is used for generating continuous laser seeds; the laser amplification module is used for amplifying the pulse laser and the continuous laser; the laser electric control system is used for supplying power to the laser and controlling the working mode of the laser. The device has three laser output modes, namely pulse laser output, continuous laser output and synchronous pulse laser and continuous laser output. The laser provided by the invention is compact in structure, integrally welded, shares the laser amplification module, has no space structure, is simple in working mode switching, ensures the stability and reliability of the system, and saves the cost.

Description

Technical Field

[0001] The invention relates to the technical field of optical fiber lasers, in particular to a pulse / continuous integrated optical fiber laser. Background Art

[0002] Fiber lasers have the advantages of good beam quality and high conversion efficiency, and are widely used in industrial processing. Continuous fiber lasers have high output power and are mainly used in laser cutting, welding, cladding, and 3D printing. Pulsed fiber lasers have the characteristics of high peak power and high energy, and are mainly used in laser cleaning and precision processing. In some scenarios, the combination of the two can produce some new applications, such as the laser shield machine based on composite laser perforation described in ZL202011407490.9. The application scenarios of the two lasers are different. If the characteristics of both continuous lasers and pulsed lasers are required, two lasers are required, which is more expensive.

[0003] At present, fiber lasers that achieve continuous and pulsed outputs either combine continuous laser and pulsed laser for output, such as patent US19910658920A; or separate continuous laser and pulsed laser from a seed source through a fiber splitter and then amplify and output them separately, such as ZL200910079918.9; or switch to pulsed laser or continuous laser amplified output through a flange, such as patent ZL201310205711.8; or adjust the central wavelength of a low-reflection Bragg grating to achieve continuous or pulsed laser output, such as patent ZL201310471121.X.

[0004] The existing technology realizes pulse and continuous laser output by either combining two lasers, which is costly; or it is impossible to output continuous and pulsed lasers in the same optical fiber, resulting in the need for different shaping systems when applying lasers; or it is necessary to switch between the continuous and pulsed working modes, and it is impossible to output continuous and pulsed lasers at the same time. This limits the engineering and application of continuous / pulsed optical fibers. Summary of the invention

[0005] In order to solve at least one technical problem in the background technology, the present invention provides a pulse / continuous integrated fiber laser with a compact structure, integrated fusion of pulse laser and continuous laser, a shared laser amplification module, no spatial structure, multiple working modes, and simple switching of working modes, which not only ensures the stability and reliability of the system, but also saves costs.

[0006] To achieve the above-mentioned purpose, the present invention provides a pulse / continuous integrated fiber laser, comprising: a pulse laser module, a continuous laser module, a laser amplification module and a laser electronic control system; the pulse laser module is used to generate a pulse laser seed; the continuous laser module is used to generate a continuous laser seed and is fused with the pulse laser module; the laser amplification module is used to amplify the pulse laser and the continuous laser and is fused with the continuous laser module; the laser electronic control system is electrically connected to the pulse laser module, the continuous laser module and the laser amplification module respectively, and is used to power the laser and control the laser working mode.

[0007] Furthermore, the pulse laser module includes a low-power pulse seed source and a pre-amplification system; the low-power pulse seed source is used to generate pulse laser; the pre-amplification system is fused with the low-power pulse seed source to pre-amplify the pulse laser signal.

[0008] Furthermore, the low-power pulse seed source adopts a pulse laser source modulated by a semiconductor, or a pulse laser source modulated by electro-optic modulation, acousto-optic modulation, or gain switching technology.

[0009] Furthermore, the pre-amplification system comprises a first isolator, a first pump source, a first combiner, a first gain fiber and a second isolator; the pre-amplification system is a single-stage pre-amplification or a multi-stage pre-amplification.

[0010] The low-power pulse seed source, the first isolator, the first beam combiner, the first gain optical fiber and the second isolator are fused in sequence; the first pump source is connected to the pump input end of the first beam combiner.

[0011] Furthermore, the continuous laser module includes a second pump source, a second beam combiner, a high-reflectivity fiber Bragg grating, a second gain fiber, a low-reflectivity fiber Bragg grating and a third isolator; the second isolator, the second beam combiner, the high-reflectivity fiber Bragg grating, the second gain fiber, the low-reflectivity fiber Bragg grating and the third isolator are fused in sequence; the second pump source is connected to the pump input end of the second beam combiner.

[0012] Furthermore, the laser amplification module includes a third pump source, a third beam combiner, a third gain fiber and a laser output head; the third isolator, the third beam combiner, the third gain fiber and the laser output head are fused in sequence, and the third pump source is connected to the pump input end of the third beam combiner.

[0013] Furthermore, the laser amplification module is a single-stage amplification module or a multi-stage amplification module.

[0014] The beneficial effects of the present invention are: 1) The present invention has three laser working modes: pulse laser, continuous laser, and pulse / continuous laser synchronous output; in the synchronous output mode, the output power ratio of pulse laser and continuous laser is adjustable.

[0015] 2) The working mode of the present invention is controlled by an electronic control system, and the mode switching is simple and efficient.

[0016] 3) The three working modes of the present invention are all output from the same optical fiber in the same amplification system, which is beneficial to the beam shaping of the output laser during application.

[0017] 4) The present invention is an all-fiber structure and integrated design, which is simple and compact, improves the stability of the laser system and saves costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of the present invention; Figure 2 This is a spectrum diagram of the pulsed laser working mode of the present invention; Figure 3 It is a frequency diagram of the pulse laser working mode of the present invention; Figure 4 This is a spectrum diagram of the present invention under the continuous laser working mode; Figure 5 This is a spectrum diagram of the present invention in the simultaneous working mode of pulse laser and continuous laser; Figure 6 This is a frequency diagram of the pulse laser and continuous laser working simultaneously in the present invention.

[0019] Among them, in the figure: a-pulse laser module, b-continuous laser module, c-laser amplification module, 1-low-power pulse seed source, 2-first isolator, 3-first pump source, 4-first combiner, 5-first gain fiber, 6-second isolator, 7-second pump source, 8-second combiner, 9-high reflectivity fiber Bragg grating, 10-second gain fiber, 11-low reflectivity fiber Bragg grating, 12-third isolator, 13-third pump source, 14-third combiner, 15-third gain fiber, 16-laser output head. DETAILED DESCRIPTION

[0020] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present application described here. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0022] In the present application, the terms "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inner", "outer", "middle", "vertical", "horizontal", "lateral", "longitudinal" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings. These terms are mainly used to better describe the present application and its embodiments, and are not used to limit the indicated devices, elements or components to have a specific orientation, or to be constructed and operated in a specific orientation.

[0023] In addition, some of the above terms may be used to express other meanings in addition to indicating orientation or positional relationship. For example, the term "on" may also be used to express a certain dependency or connection relationship in some cases. For those of ordinary skill in the art, the specific meanings of these terms in this application can be understood according to specific circumstances.

[0024] In addition, the terms "installed", "set", "provided with", "connected", "connected", and "socketed" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection, or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be an internal connection between two devices, elements, or components. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0025] To achieve the above purpose, Figure 1As shown, the present invention provides a pulse / continuous integrated fiber laser, including: a pulse laser module a, a continuous laser module b, a laser amplification module c and a laser electronic control system; the pulse laser module a is used to generate a pulse laser seed; the continuous laser module b is used to generate a continuous laser seed, and is fused with the pulse laser module a; the laser amplification module c is used to amplify the pulse laser and the continuous laser, and is fused with the continuous laser module b; the laser electronic control system is electrically connected to the pulse laser module a, the continuous laser module b, and the laser amplification module c, respectively, for powering the laser and controlling the laser working mode. The laser amplification module c can be a single-stage amplification or a multi-stage amplification. The pulse laser module a, the continuous laser module b and the laser amplification module c are fused into one without any spatial structure.

[0026] In the pulse laser working mode, the pulse laser module a and the laser amplifying module c are controlled to work, and the continuous laser module b does not work; in the continuous laser working mode, the continuous laser module b and the laser amplifying module c are controlled to work, and the pulse laser module a does not work; in the mode where the pulse laser and the continuous laser work at the same time, the pulse laser module a, the continuous laser module b and the laser amplifying module c work at the same time. In this case, it is necessary to control the pump power of the pulse laser module a and the continuous laser module b so that when the pulse laser passes through the continuous laser module b, the number of upper energy level inversion ions consumed is much smaller than the number of inversion ions pumped. At this time, part of the pump light of the continuous laser module b is used to amplify the pulse laser, and part is converted into continuous laser through the resonant cavity composed of a high reflection grating and a low reflection grating.

[0027] The pulse laser module a includes a low-power pulse seed source 1 and a pre-amplification system; the low-power pulse seed source 1 is used to generate pulsed laser; the pre-amplification system is fused with the low-power pulse seed source 1 and is used to pre-amplify the pulsed laser signal. The pre-amplification system can be a single-stage pre-amplification or a multi-stage pre-amplification.

[0028] To further optimize the technical solution, the low-power pulse seed source 1 can adopt a semiconductor-modulated pulse laser source, or a pulse laser source modulated by electro-optic modulation, acousto-optic modulation or gain switching technology.

[0029] The pre-amplification system includes a first isolator 2, a first pump source 3, a first combiner 4, a first gain fiber 5 and a second isolator 6; the low-power pulse seed source 1, the first isolator 2, the first combiner 4, the first gain fiber 5 and the second isolator 6 are fused in sequence; the first pump source 3 is connected to the pump input end of the first combiner 4.

[0030] The continuous laser module b includes a second pump source 7, a second beam combiner 8, a high reflectivity fiber Bragg grating 9, a second gain fiber 10, a low reflectivity fiber Bragg grating 11 and a third isolator 12; the second isolator 6, the second beam combiner 8, the high reflectivity fiber Bragg grating 9, the second gain fiber 10, the low reflectivity fiber Bragg grating 11 and the third isolator 12 are fused in sequence; the second pump source 7 is connected to the pump input end of the second beam combiner 8 to form a resonant cavity for generating continuous laser, and then fused with the laser amplification module c, and outputs the required laser working mode after amplification. In this embodiment, the low-power pulse seed source 1 uses a wavelength of 1064nm, and the continuous laser is generated using a grating resonant cavity of 1080nm.

[0031] The laser amplification module c includes a third pump source 13, a third beam combiner 14, a third gain fiber 15 and a laser output head 16; the third isolator 12, the third beam combiner 14, the third gain fiber 15 and the laser output head 16 are sequentially fused, and the third pump source 13 is connected to the pump input end of the third beam combiner 14. The laser amplification module c can be a single-stage amplification or a multi-stage amplification.

[0032] The present invention has three laser working modes: pulsed laser, continuous laser, and pulsed / continuous laser synchronous output. The three working modes of the present invention are all output from the same optical fiber in the same amplification system, which is beneficial to the beam shaping of the output laser when it is used. The present invention is an all-optical fiber structure and integrated design, with a simple and compact structure, which improves the stability of the laser system and saves costs. The present invention controls the operation of the pulse laser module a, the continuous laser module b, and the laser amplification module c through a laser electric control system, which can not only realize pulsed laser output and continuous laser output respectively, but also realize pulsed and continuous laser synchronous output, and the output power ratio of the pulsed laser and the continuous laser is adjustable, and the mode switching is simple and efficient.

[0033] In this embodiment, the repetition rate of the small signal pulse laser seed source is set to 100kHz, the pulse width is set to 10ns, and the average power is set to 100μW. After two stages of pre-amplification, the average power is set to 5W. In the pulse working mode, the continuous laser module b does not work, so after the pulse laser passes through the continuous laser module b, there is a certain system transmission loss (when the output power of the pulse laser module a is large, the loss has little effect on the final output power, and the continuous laser module b can also be operated in the low pumping mode to compensate for the transmission loss of the pulse laser module a. The continuous laser module b is difficult to reach the threshold of the resonant cavity in the low pumping mode, and no continuous laser will be generated). The laser amplification module c amplifies the pulse laser, and in this embodiment, it is amplified to 50W. At this time, the pulse spectrum is as follows Figure 2 As shown, the frequency spectrum is Figure 3As shown. In the continuous working mode, the pulse laser module a does not work and the output is 0. The continuous laser passes through the fiber grating resonant cavity and outputs 5W continuous laser. The laser amplification module c amplifies the continuous laser. In this embodiment, it is only amplified to 50W. The continuous spectrum is shown in Figure 4 As shown. In the synchronous working mode of pulse laser and continuous laser, the output power ratio of pulse laser module a and continuous laser module b is controlled. After amplification by laser amplifier module c, the total output power is 100W. After splitting, the 1064nm pulse laser is measured to be 50W, and the 1080nm continuous laser is 50W. The spectrum in the synchronous working mode of pulse laser and continuous laser is shown as follows Figure 5 As shown, the frequency spectrum is Figure 6 By adjusting the injection ratio of the continuous laser and pulse laser seed sources in the laser amplification module c, the competitive advantages of the two during laser amplification can be changed, thereby changing the output ratio of the pulse laser and the continuous laser.

[0034] The above description is only an example of the present invention and does not limit the technical scope of the present invention. Therefore, any modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A pulse / continuous integrated fiber laser, characterized in that: include: A pulse laser module, a continuous laser module, a laser amplification module and a laser electronic control system; the pulse laser module is used to generate a pulse laser seed; the continuous laser module is used to generate a continuous laser seed and is fused with the pulse laser module; the laser amplification module is used to amplify the pulse laser and the continuous laser and is fused with the continuous laser module; the laser electronic control system is electrically connected to the pulse laser module, the continuous laser module and the laser amplification module respectively, and is used to power the laser and control the laser working mode.

2. A pulse / continuous fiber laser as claimed in claim 1, characterized in that: The pulse laser module includes a low-power pulse seed source and a pre-amplification system; the low-power pulse seed source is used to generate pulse laser; the pre-amplification system is fused with the low-power pulse seed source to pre-amplify the pulse laser signal; the pre-amplification system is a single-stage pre-amplification or a multi-stage pre-amplification.

3. A pulse / continuous fiber laser as claimed in claim 2, characterized in that: The low-power pulse seed source adopts a semiconductor-modulated pulse laser source, or a pulse laser source modulated by electro-optical modulation, acousto-optic modulation, or gain switching technology.

4. A pulse / continuous integrated fiber laser as claimed in claim 2 or 3, characterized in that: The pre-amplification system includes a first isolator, a first pump source, a first beam combiner, a first gain fiber and a second isolator; The low-power pulse seed source, the first isolator, the first beam combiner, the first gain optical fiber and the second isolator are fused in sequence; the first pump source is connected to the pump input end of the first beam combiner.

5. The pulse / continuous integrated fiber laser according to claim 4, characterized in that: The continuous laser module comprises a second pump source, a second beam combiner, a high reflectivity fiber Bragg grating, a second gain fiber, a low reflectivity fiber Bragg grating and a third isolator; the second isolator, the second beam combiner, the high reflectivity fiber Bragg grating, the second gain fiber, the low reflectivity fiber Bragg grating and the third isolator are fused in sequence; the second pump source is connected to the pump input end of the second beam combiner.

6. The pulse / continuous integrated fiber laser according to claim 5, characterized in that: The laser amplification module includes a third pump source, a third beam combiner, a third gain fiber and a laser output head; the third isolator, the third beam combiner, the third gain fiber and the laser output head are fused in sequence, and the third pump source is connected to the pump input end of the third beam combiner.

7. The pulse / continuous fiber laser according to claim 6, characterized in that: The laser amplification module is a single-stage amplification or a multi-stage amplification.

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