Ultrahigh repetition frequency nanosecond pulse fiber laser
Through the combined structure of the seed source module and the multi-stage amplification module, the optical path design and gain distribution are optimized, and the problem of insufficient output average power of the existing ultra-high refrigeration nanosecond pulsed fiber laser is solved, and an efficient nanosecond pulsed laser output is achieved.
Patent Information
- Application Number
- CN202422496148.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-15
- Publication Date
- 2025-08-22
- Estimated Expiration
- 2034-10-15
AI Technical Summary
The current ultra-high refrigeration nanosecond pulse fiber lasers have limited output power and are less efficient in laser applications.
The combined structure of seed source module, multi-stage amplification module and output isolator is adopted to directly modulate semiconductor laser diodes and multi-stage pump lasers to perform fiber amplification, optimize the optical path design and gain distribution, and realize three-stage amplification.
It realizes a nanosecond pulse laser output with an average power of 700W, a peak power of more than 2kW, a single pulse energy of more than 0.2mJ, a frequency range of 1-80000kHz, ultra-high refrigeration, high power, and high beam quality.
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Figure CN223261053U_ABST
Abstract
Description
Technical Field
[0001] The present application belongs to the field of laser technology, and more specifically, relates to an ultra-high repetition rate nanosecond pulse fiber laser. Background Art
[0002] Ultra-high repetition rate nanosecond pulse fiber lasers are rapidly developing due to their excellent output beam quality, compact structure, high flexibility, high reliability, and maintenance-free operation. Currently, the main methods for generating ultra-high repetition rate nanosecond pulse fiber lasers include Q-switching technology, directly modulating semiconductor laser diodes, and using MOPA technology to achieve target performance through multiple fiber amplifier stages.
[0003] Nanosecond pulse lasers generated by combining Q-switching technology with MOPA technology have disadvantages such as single output pulse width and limited tuning frequency range, and cannot meet the diverse application market needs.
[0004] However, the existing ultra-high repetition rate nanosecond pulse fiber lasers have limited average output power and low laser application processing efficiency. Summary of the Invention
[0005] The purpose of the embodiments of the present application is to provide an ultra-high repetition rate nanosecond pulse fiber laser to solve the technical problems existing in the prior art of the limited average output power of the existing ultra-high repetition rate nanosecond pulse fiber laser and the low laser application processing efficiency.
[0006] To achieve the above-mentioned purpose, the technical solution adopted in this application is: to provide an ultra-high repetition rate nanosecond pulse fiber laser, comprising a seed source module part, a first-stage amplification module part, a second-stage amplification module part, a third-stage amplification module part and an output isolator; the seed source module part comprises a directly modulated semiconductor laser diode and a first online isolator connected in sequence;
[0007] The first-stage amplification module includes a first pump laser, a first beam combiner, a first ytterbium-doped double-clad optical fiber, and a second in-line isolator connected in sequence; the output end of the first in-line isolator is connected to the signal end of the first beam combiner, and the output end of the first pump laser is connected to the pump end of the first beam combiner;
[0008] The secondary amplification module comprises a second pump laser, and a second ytterbium-doped double-clad optical fiber, a second beam combiner and a third online isolator connected in sequence; the pump end of the second beam combiner is connected to the second pump laser;
[0009] The three-stage amplification module includes a third pump laser, and a mode field adapter, a third ytterbium-doped double-clad optical fiber and a third combiner connected in sequence; the output end of the third in-line isolator is connected to the input end of the mode field adapter; the pump end of the third combiner is connected to the third pump laser;
[0010] The output isolator is connected to the signal optical fiber of the third combiner.
[0011] Optionally, the directly modulated semiconductor laser diode is a commercial SLD semiconductor laser diode with a central wavelength of 1064 nm, a line width less than 15 nm, an output fiber of Hi1060 fiber, a pulse output state, a pulse width range of 10-280 ns, and a repetition frequency of 1-80000 kHz.
[0012] Optionally, the first in-line isolator has a central wavelength of 1059 nm, an operating bandwidth of 16 nm, an input optical fiber of Hi1060 optical fiber, an output optical fiber of 10 / 125 single-clad optical fiber, an average power tolerance of 800 mW, an insertion loss of less than 3 dB, and an isolation greater than 25 dB;
[0013] The second in-line isolator has a central wavelength of 1062 nm, an operating bandwidth of 20 nm, a 10 / 125 single-clad optical fiber as the input fiber, a 10 / 125 single-clad optical fiber as the output fiber, an average power tolerance of 10 W, an insertion loss of less than 1.5 dB, and an isolation greater than 25 dB;
[0014] The central wavelength of the third online isolator is 1062nm, the working bandwidth is 20nm, the input optical fiber is 10 / 400 single-clad optical fiber, the output optical fiber is 10 / 400 single-clad optical fiber, the average power it withstands is 60W, the insertion loss is less than 1dB, and the isolation is greater than 25dB.
[0015] Optionally, the first pump laser provides pump excitation to the first ytterbium-doped double-clad optical fiber, has an output power greater than 15 W, a central wavelength of 915 nm, and an output optical fiber that is a 105 / 125 multimode optical fiber;
[0016] The second pump laser provides pump excitation for the second ytterbium-doped double-clad optical fiber, has an output power greater than 180 W, a central wavelength of 976 nm, and an output optical fiber that is a 135 / 155 multimode optical fiber;
[0017] The third pump laser provides pump excitation for the third ytterbium-doped double-clad optical fiber, has an output power greater than 500 W, a central wavelength of 976 nm, and an output optical fiber that is a 220 / 242 multimode optical fiber.
[0018] Optionally, the signal fiber of the first combiner is a 10 / 125 double-clad fiber, the pump fiber is a 105 / 125 multimode fiber, the pump light coupling efficiency is greater than 95%, the signal light withstand power is greater than 5W, and the pump light withstand power is greater than 15W;
[0019] The signal fiber of the second combiner is a 10 / 400 double-clad fiber, the pump fiber is a 135 / 155 multimode fiber, the pump light coupling efficiency is greater than 95%, the signal light power is greater than 60W, and the pump light power is greater than 180W;
[0020] The signal fiber of the third combiner is a 14 / 400 double-clad fiber, the pump fiber is a 220 / 242 multimode fiber, the pump light coupling efficiency is greater than 95%, the signal light withstand power is greater than 700W, and the pump light withstand power is greater than 500W.
[0021] Optionally, the first ytterbium-doped double-clad optical fiber is a commercial ytterbium-doped 10 / 125 double-clad optical fiber, and the length of the optical fiber is determined according to the actual absorption coefficient of the optical fiber.
[0022] Optionally, the second ytterbium-doped double-clad optical fiber is a commercial ytterbium-doped 10 / 400 double-clad optical fiber, and the length of the optical fiber is determined according to the actual absorption coefficient of the optical fiber.
[0023] Optionally, the third ytterbium-doped double-clad optical fiber is a commercial ytterbium-doped 14 / 400 double-clad optical fiber, and the length of the optical fiber is determined according to the actual absorption coefficient of the optical fiber.
[0024] Optionally, the input end of the mode field adapter is a 10 / 400 double-clad optical fiber, and the output end is a 14 / 400 double-clad optical fiber, and the average power it can withstand is greater than 60W.
[0025] Optionally, the operating wavelength of the output isolator is 1064 nm, and the input optical fiber is a 14 / 400 double-clad optical fiber, wherein the average power it withstands is greater than 700 W, the peak power it withstands is greater than 3 kW, and the isolation is greater than 25 dB.
[0026] The beneficial effects of the ultra-high repetition rate nanosecond pulse fiber laser provided by the present application are as follows: compared with the existing technology, the ultra-high repetition rate nanosecond pulse fiber laser of the present application utilizes a reasonably designed output waveform, a more appropriate optical path selection, and an optimized gain distribution to maintain a good output spectrum for each stage of the fiber amplifier. After amplification by three stages of amplifiers, it achieves an average power of 700W, a peak power greater than 2kW, a single pulse energy greater than 0.2mJ, and a frequency range of 1-80000kHz, thereby achieving ultra-high repetition rate, high power, and high beam quality nanosecond pulse laser output. BRIEF DESCRIPTION OF THE DRAWINGS
[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments or descriptions of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.
[0028] Figure 1 A schematic structural diagram of an ultra-high repetition rate nanosecond pulse fiber laser provided in an embodiment of the present application.
[0029] Among them, the reference numerals in the figures are:
[0030] 1-seed source module; 11-directly modulated semiconductor laser diode; 12-first online isolator;
[0031] 2-first stage amplification module; 21-first pump laser; 22-first beam combiner; 23-first ytterbium-doped double-clad fiber; 24-second in-line isolator; 25-coupler; 26-fiber-coupled photodetector;
[0032] 3-secondary amplification module; 31-second ytterbium-doped double-clad fiber; 32-second beam combiner; 33-second pump laser; 34-third online isolator;
[0033] 4- three-stage amplification module; 41- mode field adapter; 42- third ytterbium-doped double-clad fiber; 43- third beam combiner; 44- third pump laser;
[0034] 51-Output isolator. DETAILED DESCRIPTION
[0035] In order to make the technical problems, technical solutions and beneficial effects to be solved by this application more clearly understood, this application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.
[0036] It should be noted that when an element is referred to as being “fixed on” or “disposed on” another element, it may be directly on the other element or indirectly on the other element. When an element is referred to as being “connected to” another element, it may be directly connected to the other element or indirectly connected to the other element.
[0037] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.
[0038] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. Throughout the description of this application, "plurality" means two or more, unless otherwise specifically defined.
[0039] See also Figure 1 , the ultra-high repetition rate nanosecond pulse fiber laser provided by the embodiment of the present application is now described. The ultra-high repetition rate nanosecond pulse fiber laser comprises a seed source module part 1, a first-stage amplification module part 2, a second-stage amplification module part 3, a third-stage amplification module part 4 and an output isolator 51; the seed source module part 1 comprises a directly modulated semiconductor laser diode 11 and a first online isolator 12 connected in sequence; the first-stage amplification module part 2 comprises a first pump laser 21, and a first combiner 22, a first ytterbium-doped double-clad fiber 23, and a second online isolator 24 connected in sequence; the output end of the first online isolator 12 is connected to the signal end of the first combiner 22, and the output end of the first pump laser 21 is connected to the pump end of the first combiner 22. The secondary amplification module part 3 includes a second pump laser 33, and a second ytterbium-doped double-clad fiber 31, a second combiner 32 and a third online isolator 34 connected in sequence; the pump end of the second combiner 32 is connected to the second pump laser 33; the tertiary amplification module part 4 includes a third pump laser 44, and a mode field adapter 41, a third ytterbium-doped double-clad fiber 42 and a third combiner 43 connected in sequence; the output end of the third online isolator 34 is connected to the input end of the mode field adapter 41; the pump end of the third combiner 43 is connected to the third pump laser 44; and the output isolator 51 is connected to the signal fiber of the third combiner 43.
[0040] The ultra-high repetition rate nanosecond pulse fiber laser provided in the present application, compared with the prior art, the ultra-high repetition rate nanosecond pulse fiber laser of the embodiment of the present application utilizes a reasonably designed output waveform, a more appropriate optical path selection, and an optimized gain distribution to maintain a good output spectrum for each stage of the fiber amplifier. After amplification by three stages of amplifiers, it achieves an average power of 700W, a peak power greater than 2kW, a single pulse energy greater than 0.2mJ, and a frequency range of 1-80000kHz, thereby achieving ultra-high repetition rate, high power, and high beam quality nanosecond pulse laser output.
[0041] In one embodiment of the present application, the directly modulated semiconductor laser diode 11 is a commercial SLD semiconductor laser diode with a central wavelength of 1064 nm, a line width less than 15 nm, an output fiber of Hi1060 fiber, an output state of pulse, a pulse width range of 10-280 ns, and a repetition frequency of 1-80000 kHz.
[0042] In an embodiment of the present application, a directly modulated semiconductor laser diode 11 is used to provide seed light for the laser. The directly modulated semiconductor laser diode 11 uses a commercial SLD semiconductor laser diode with a total of 28 pulse widths to choose from, some of which have a repetition frequency of less than 80,000 kHz, and a duty cycle of a 280ns pulse width as high as 99.5%.
[0043] In one embodiment of the present application, the first in-line isolator 12 has a central wavelength of 1059 nm, an operating bandwidth of 16 nm, an input fiber of Hi1060 fiber, an output fiber of 10 / 125 single-clad fiber, an average power handling capacity of 800 mW, an insertion loss of less than 3 dB, and an isolation greater than 25 dB. The second in-line isolator 24 has a central wavelength of 1062 nm, an operating bandwidth of 20 nm, an input fiber of 10 / 125 single-clad fiber, an output fiber of 10 / 125 single-clad fiber, an average power handling capacity of 10 W, an insertion loss of less than 1.5 dB, and an isolation greater than 25 dB. The third in-line isolator 34 has a central wavelength of 1062 nm, an operating bandwidth of 20 nm, an input fiber of 10 / 400 single-clad fiber, an output fiber of 10 / 400 single-clad fiber, an average power handling capacity of 60 W, an insertion loss of less than 1 dB, and an isolation greater than 25 dB.
[0044] In this embodiment, the inline isolator optically isolates the return light at the isolator's output, protecting the stable operation of the entire fiber laser system. The inline isolator also integrates a bandpass filter to optimize the output spectral linewidth; a mode field adapter enables the transition of optical signals from thin to thick fiber without degrading beam quality. The isolator's power handling capacity is selected based on the input power.
[0045] In one embodiment of the present application, a first pump laser 21 provides pump excitation to a first ytterbium-doped double-clad fiber 23, with an output power greater than 15 W, a center wavelength of 915 nm, and an output fiber being a 105 / 125 multimode fiber; a second pump laser 33 provides pump excitation to a second ytterbium-doped double-clad fiber 31, with an output power greater than 180 W, a center wavelength of 976 nm, and an output fiber being a 135 / 155 multimode fiber; a third pump laser 44 provides pump excitation to a third ytterbium-doped double-clad fiber 42, with an output power greater than 500 W, a center wavelength of 976 nm, and an output fiber being a 220 / 242 multimode fiber.
[0046] In this embodiment, the pump wavelength determines the pump absorption coefficient of the active fiber. For design considerations, a 915 nm pump source is sufficient for the first pump laser 21. The second and third pump lasers 33 and 44 use a 976 nm pump source to maximize the pump absorption coefficient, optimize the second and third stage optical paths, and achieve optimal optical performance indicators.
[0047] In one embodiment of the present application, the signal fiber of the first combiner 22 is a 10 / 125 double-clad fiber, the pump fiber is a 105 / 125 multimode fiber, the pump light coupling efficiency is greater than 95%, the signal light withstand power is greater than 5W, and the pump light withstand power is greater than 15W; the signal fiber of the second combiner 32 is a 10 / 400 double-clad fiber, the pump fiber is a 135 / 155 multimode fiber, the pump light coupling efficiency is greater than 95%, the signal light withstand power is greater than 60W, and the pump light withstand power is greater than 180W; the signal fiber of the third combiner 43 is a 14 / 400 double-clad fiber, the pump fiber is a 220 / 242 multimode fiber, the pump light coupling efficiency is greater than 95%, the signal light withstand power is greater than 700W, and the pump light withstand power is greater than 500W.
[0048] In one embodiment of the present application, the first ytterbium-doped double-clad optical fiber 23 is a commercial ytterbium-doped 10 / 125 double-clad optical fiber, and the length of the optical fiber is determined according to the actual absorption coefficient of the optical fiber.
[0049] In one embodiment of the present application, the second ytterbium-doped double-clad optical fiber 31 is a commercial ytterbium-doped 10 / 400 double-clad optical fiber, and the length of the optical fiber is determined according to the actual absorption coefficient of the optical fiber.
[0050] In one embodiment of the present application, the third ytterbium-doped double-clad optical fiber 42 is a commercial ytterbium-doped 14 / 400 double-clad optical fiber, and the length of the optical fiber is determined according to the actual absorption coefficient of the optical fiber.
[0051] In one embodiment of the present application, the input end of the mode field adapter 41 is a 10 / 400 double-clad optical fiber, and the output end is a 14 / 400 double-clad optical fiber, which can withstand an average power greater than 60W.
[0052] In this embodiment, the mode field adapter 41 functions to achieve the transition of signal light from the thin optical fiber to the thick optical fiber without degradation of the beam quality and loss of signal power.
[0053] In one embodiment of the present application, the operating wavelength of the output isolator 51 is 1064 nm, the input optical fiber is a 14 / 400 double-clad optical fiber, the average power it can withstand is greater than 700 W, the peak power it can withstand is greater than 3 kW, and the isolation is greater than 25 dB.
[0054] In this embodiment, the first-stage amplifier module 2, the second-stage amplifier module 3, and the third-stage amplifier module 4 all employ a cladding-pumped MOPA structure to amplify the signal light. Each amplifier module utilizes commercial ytterbium-doped double-clad fiber, and the pump light source utilizes a 915nm and 976nm multimode semiconductor laser. The three-stage amplification structure amplifies the seed source power to an average power of 700W, a peak power exceeding 2kW, and a single pulse energy exceeding 0.2mJ. Within a frequency range of 1-80,000kHz, this achieves ultra-high repetition rate, high power, and high beam quality nanosecond pulse laser output. At 700W output power, the 280ns output achieves a near 100% duty cycle, and the average power reaches the theoretical limit at a peak power of 2kW.
[0055] The optical path structure of this embodiment is compact, simple, and has excellent output beam quality. It is the industry's first ideal light source for ultra-fast laser precision processing applications.
[0056] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application should be included in the scope of protection of the present application.
Claims
1. An ultra-high repetition rate nanosecond pulse fiber laser, characterized in that: include: A seed source module part (1), the seed source module part (1) comprising a directly modulated semiconductor laser diode (11) and a first online isolator (12) connected in sequence; A first-stage amplification module part (2), the first-stage amplification module part (2) includes a first pump laser (21), and a first beam combiner (22), a first ytterbium-doped double-clad optical fiber (23), and a second online isolator (24) connected in sequence; the output end of the first online isolator (12) is connected to the signal end of the first beam combiner (22), and the output end of the first pump laser (21) is connected to the pump end of the first beam combiner (22); A secondary amplification module part (3), the secondary amplification module part (3) comprising a second pump laser (33), and a second ytterbium-doped double-clad optical fiber (31), a second beam combiner (32), and a third online isolator (34) connected in sequence; a pump end of the second beam combiner (32) is connected to the second pump laser (33); A three-stage amplification module part (4), the three-stage amplification module part (4) includes a third pump laser (44), and a mode field adapter (41), a third ytterbium-doped double-clad optical fiber (42), and a third combiner (43) connected in sequence; the output end of the third in-line isolator (34) is connected to the input end of the mode field adapter (41); the pump end of the third combiner (43) is connected to the third pump laser (44); and An output isolator (51); the output isolator (51) is connected to the signal optical fiber of the third combiner (43).
2. The ultra-high repetition rate nanosecond pulse fiber laser according to claim 1, characterized in that: The directly modulated semiconductor laser diode (11) is a commercial SLD semiconductor laser diode with a central wavelength of 1064nm, a line width of less than 15nm, an output optical fiber of Hi1060 optical fiber, an output state of pulses, a pulse width range of 10-280ns, and a repetition frequency of 1-80000kHz.
3. The ultra-high repetition rate nanosecond pulse fiber laser according to claim 1, characterized in that: The first online isolator (12) has a central wavelength of 1059 nm, an operating bandwidth of 16 nm, an input optical fiber of Hi1060 optical fiber, an output optical fiber of 10 / 125 single-clad optical fiber, an average power tolerance of 800 mW, an insertion loss of less than 3 dB, and an isolation greater than 25 dB; The second in-line isolator (24) has a central wavelength of 1062 nm, an operating bandwidth of 20 nm, an input optical fiber of 10 / 125 single-clad optical fiber, an output optical fiber of 10 / 125 single-clad optical fiber, an average power withstand of 10 W, an insertion loss of less than 1.5 dB, and an isolation greater than 25 dB; The third online isolator (34) has a central wavelength of 1062nm, a working bandwidth of 20nm, an input optical fiber of 10 / 400 single-clad optical fiber, an output optical fiber of 10 / 400 single-clad optical fiber, an average power withstand of 60W, an insertion loss of less than 1dB, and an isolation greater than 25dB.
4. The ultra-high repetition rate nanosecond pulse fiber laser according to claim 1, characterized in that: The first pump laser (21) provides pump excitation to the first ytterbium-doped double-clad optical fiber (23), the output power is greater than 15W, the central wavelength is 915nm, and the output optical fiber is a 105 / 125 multimode optical fiber; The second pump laser (33) provides pump excitation for the second ytterbium-doped double-clad optical fiber (31), has an output power greater than 180W, a central wavelength of 976nm, and an output optical fiber that is a 135 / 155 multimode optical fiber; The third pump laser (44) provides pump excitation for the third ytterbium-doped double-clad optical fiber (42), has an output power greater than 500W, a central wavelength of 976nm, and an output optical fiber that is a 220 / 242 multimode optical fiber.
5. The ultra-high repetition rate nanosecond pulse fiber laser according to claim 1, characterized in that: The signal fiber of the first combiner (22) is a 10 / 125 double-clad fiber, the pump fiber is a 105 / 125 multimode fiber, the pump light coupling efficiency is greater than 95%, the signal light withstand power is greater than 5W, and the pump light withstand power is greater than 15W; The signal fiber of the second combiner (32) is a 10 / 400 double-clad fiber, the pump fiber is a 135 / 155 multimode fiber, the pump light coupling efficiency is greater than 95%, the signal light withstand power is greater than 60W, and the pump light withstand power is greater than 180W; The signal fiber of the third combiner (43) is a 14 / 400 double-clad fiber, the pump fiber is a 220 / 242 multimode fiber, the pump light coupling efficiency is greater than 95%, the signal light withstand power is greater than 700W, and the pump light withstand power is greater than 500W.
6. The ultra-high repetition rate nanosecond pulse fiber laser according to claim 1, characterized in that: The first ytterbium-doped double-clad optical fiber (23) is a commercial ytterbium-doped 10 / 125 double-clad optical fiber, and the length of the optical fiber is determined according to the actual absorption coefficient of the optical fiber.
7. The ultra-high repetition rate nanosecond pulse fiber laser according to claim 6, characterized in that: The second ytterbium-doped double-clad optical fiber (31) is a commercial ytterbium-doped 10 / 400 double-clad optical fiber, and the optical fiber length is determined according to the actual absorption coefficient of the optical fiber.
8. The ultra-high repetition rate nanosecond pulse fiber laser according to claim 7, characterized in that: The third ytterbium-doped double-clad optical fiber (42) is a commercial ytterbium-doped 14 / 400 double-clad optical fiber, and the length of the optical fiber is determined according to the actual absorption coefficient of the optical fiber.
9. The ultra-high repetition rate nanosecond pulse fiber laser according to claim 1, characterized in that: The input end of the mode field adapter (41) is a 10 / 400 double-clad optical fiber, and the output end is a 14 / 400 double-clad optical fiber, and can withstand an average power greater than 60W.
10. The ultra-high repetition rate nanosecond pulse fiber laser according to any one of claims 1 to 9, characterized in that: The output isolator (51) has an operating wavelength of 1064 nm, an input optical fiber of 14 / 400 double-clad optical fiber, an average power of more than 700 W, a peak power of more than 3 kW, and an isolation of more than 25 dB.