Pulse width compression device for compressing injected laser pulse by using SBS (Styrene Butadiene Styrene) process
Through the SBS process and fiber combination technology, the random feedback of pump light and single-mode fiber is used to achieve effective pulse width compression of nanosecond and microsecond laser pulses, and solve the problems of complex and large optical paths in the existing technology. Achieve efficient pulse width compression effect.
Patent Information
- Application Number
- CN202420743970.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-11
- Publication Date
- 2024-12-27
- Estimated Expiration
- 2034-04-11
AI Technical Summary
The prior art is difficult to effectively compress nanosecond and microsecond laser pulses, resulting in complex optical paths and large volumes.
Using the SBS process, the laser light source, the fiber isolator, the fiber beam combiner, the gain fiber, the first single mode fiber and the second single mode fiber are used to provide pump light, and the laser pulse is amplified in the gain fiber and Multi-order SBS process is carried out through single-mode optical fiber to achieve pulse width compression.
Effective pulse width compression for nanosecond and microsecond pulses is achieved. The structure is simple, the compression effect is good, and the pulse width is much smaller than the width of the incident pulse.
Smart Images
Figure CN222261725U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of laser pulse compression, and in particular relates to a pulse width compression device which compresses injected laser pulses by utilizing an SBS process. Background Art
[0002] In laser physics, laser pulse compression and generation are key technologies for achieving high-power and high-intensity laser output. The combination of nonlinear fiber devices and grating devices is mainly used to compress pulses with dispersion compensation, which is usually applied to picosecond and even femtosecond pulses. However, for nanosecond pulses and microsecond pulses that do not have the characteristics of broadening and compression, they often need to be compressed by amplification in the compression system, making the entire optical path more complicated and larger in size. Summary of the invention
[0003] The technical problem to be solved by the utility model is to provide a pulse width compression device which compresses injected laser pulses by using the SBS process, and realizes pulse width compression of nanosecond pulses and microsecond pulses by using the SBS process.
[0004] In order to solve the above technical problems, an embodiment of the utility model provides a pulse width compression device for compressing injected laser pulses using the SBS process, including a laser light source, an optical fiber isolator, an optical fiber combiner, at least one pump source, a gain fiber, a first single-mode optical fiber and a second single-mode optical fiber. The laser light source is connected to the optical fiber combiner through the optical fiber isolator, and the pump source is connected to the optical fiber isolator; one end of the first single-mode optical fiber is connected to one end of the gain optical fiber, and the other end of the gain optical fiber is connected to the output end of the optical fiber combiner; the input end of the optical fiber combiner is connected to one end of the second single-mode optical fiber.
[0005] As a further improvement of the embodiment of the utility model, the pulse width of the laser pulse output by the laser light source is in the nanosecond level or microsecond level.
[0006] As a further improvement of an embodiment of the utility model, the fiber optic combiner is a (N+1)×1 type fiber optic combiner; there are N-1 pump sources; and N is an integer greater than 1.
[0007] As a further improvement of an embodiment of the utility model, the gain fiber is a fiber doped with rare earth elements, and the doping element is one or more of ytterbium, thulium, holmium, bismuth, samarium, erbium, and chromium.
[0008] As a further improvement to an embodiment of the utility model, the length of the first single-mode optical fiber is greater than or equal to 1 m.
[0009] As a further improvement to an embodiment of the utility model, the length of the second single-mode optical fiber is greater than or equal to 1 m.
[0010] As a further improvement of the embodiment of the utility model, the other end of the first single-mode optical fiber has a bevel angle, and the angle of the bevel angle is 8°.
[0011] As a further improvement of the embodiment of the utility model, the other end of the second single-mode optical fiber has a bevel angle, and the angle of the bevel angle is 8°.
[0012] Compared with the prior art, the technical solution of the utility model has the following beneficial effects:
[0013] The embodiment of the utility model is a pulse width compression device for compressing an injected laser pulse by using an SBS process. A laser light source is used to output an injected laser pulse with a pulse width of nanoseconds or microseconds. The injected laser pulse is injected into a gain fiber through an optical fiber isolator through an optical fiber combiner. At the same time, a pump source outputs pump light, which is injected into the gain fiber through the optical fiber combiner. The gain fiber absorbs the pump light and amplifies the injected laser pulse. The amplified injected laser pulse propagates in the direction of a first single-mode optical fiber, and after receiving random Rayleigh feedback in the single-mode optical fiber, it is reversed and propagates in the direction of a second single-mode optical fiber. During the propagation process, the first single-mode optical fiber and the second single-mode optical fiber are used to reduce the stimulated Brillouin scattering threshold, and random feedback of Rayleigh scattering is provided, so that the injected laser pulse undergoes a multi-order SBS (stimulated Brillouin) process and the pulse width is compressed. The pulse width compression device provided by the utility model, after the incident nanosecond pulse or microsecond pulse triggers the SBS effect, the energy will be coupled and converted through the incident pulse and the triggered Stokes light, the Stokes pulse front edge extracts a large amount of energy of the incident pulse to quickly increase the peak power, the pulse width is much smaller than the incident pulse width, and the pulse width compression of nanosecond pulses and microsecond pulses can be achieved, the structure is simple, and the pulse width compression effect is good. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Figure 1 It is a structural schematic diagram of a pulse width compression device for compressing injected laser pulses using the SBS process according to an embodiment of the utility model.
[0015] The figure includes: a laser light source 1, an optical fiber isolator 2, an optical fiber combiner 3, a pump source 4, a gain optical fiber 5, a first single-mode optical fiber 6, and a second single-mode optical fiber 7. DETAILED DESCRIPTION
[0016] The technical solution of the utility model is described in detail below in conjunction with the accompanying drawings.
[0017] The present invention provides a pulse width compression device for compressing injected laser pulses using the SBS process. Figure 1As shown, it includes a laser light source 1, a fiber isolator 2, a fiber combiner 3, at least one pump source 4, a gain fiber 5, a first single-mode fiber 6, and a second single-mode fiber 7. The laser light source 1 is connected to the fiber combiner 3 through the fiber isolator 2, and the pump source 4 is connected to the fiber combiner 3. One end of the first single-mode fiber 6 is connected to one end of the gain fiber 5, and the other end of the gain fiber 5 is connected to the output end of the fiber combiner 3. The input end of the fiber combiner 3 is connected to one end of the second single-mode fiber 7.
[0018] Among them, the laser light source 1 is used to provide an injected laser pulse, the pulse width of the laser pulse output by the laser light source 1 is in the nanosecond or microsecond level, and the wavelength of the injected laser pulse is 0.1 to 100 μm. The optical fiber isolator 2 is located on the laser output path of the laser light source 1, and is used to isolate the return light and protect the laser light source 1. There are N-1 pump sources 4, which are used to provide pump light. N is an integer greater than 1. For example, N=2, 3, 4 or 5. The optical fiber combiner 3 is an (N+1)×1 type optical fiber combiner, which is used to input the injected laser pulse and the pump light into the gain fiber 5. The gain fiber 5 is used to absorb the pump light and amplify the injected laser pulse. The first single-mode optical fiber 6 and the second single-mode optical fiber 7 are used to reduce the stimulated Brillouin scattering threshold and provide random feedback of Rayleigh scattering.
[0019] The pulse width compression device of this embodiment adopts a laser light source to output an injection laser pulse with a pulse width of nanoseconds or microseconds, which is injected into the gain fiber through a fiber isolator through a fiber combiner, and at the same time, the pump source outputs pump light, which is injected into the gain fiber through a fiber combiner. The gain fiber absorbs the pump light and amplifies the injection laser pulse. The amplified injection laser pulse propagates in the direction of the first single-mode fiber, and after receiving random Rayleigh feedback in the single-mode fiber, it reverses and propagates in the direction of the second single-mode fiber. During the propagation process, the first single-mode fiber and the second single-mode fiber are used to reduce the stimulated Brillouin scattering threshold, and provide random feedback of Rayleigh scattering, so that the injection laser pulse undergoes a multi-order SBS (stimulated Brillouin) process and the pulse width is compressed. The pulse width compression device provided by the utility model can realize the pulse width compression of nanosecond pulses and microsecond pulses, has a simple structure, and has a good pulse width compression effect.
[0020] Preferably, the gain fiber 5 is a fiber doped with rare earth elements, and the doping element is one or more of ytterbium, thulium, holmium, bismuth, samarium, erbium, and chromium.
[0021] Preferably, the lengths of the first single-mode optical fiber 6 and the second single-mode optical fiber 7 are both greater than or equal to 1 m. The lengths of the single-mode optical fibers on both sides of the gain optical fiber affect the Brillouin scattering threshold, and the longer the optical fiber, the lower the threshold. In this embodiment, the lengths of the single-mode optical fibers on both sides of the gain optical fiber are set to be greater than or equal to 1 m, which can ensure that SBS can be triggered.
[0022] Preferably, the other end of the first single-mode optical fiber (6) (the end not connected to the gain optical fiber) and the other end of the second single-mode optical fiber 7 (the end not connected to the optical fiber combiner) both have a bevel angle, and the angle of the bevel angle is 8°. The bevel angle is set on the end faces of the two single-mode optical fibers to prevent the optical fiber end faces from providing feedback, and to ensure that the feedback on the left and right sides is provided by Rayleigh scattering in the single-mode optical fiber.
[0023] A specific example is provided below.
[0024] The laser light source 1 uses an actively Q-switched pulse fiber laser with an average output power of 1W, a wavelength of 1064nm, and a pulse width of 50ns. The output optical coupling fiber uses a 10μm / 125μm passive optical fiber to connect to the optical fiber isolator. The optical fiber combiner 3 uses a 10μm / 125μm (2+1)×1 pump combiner. The pump source 4 uses a 10W semiconductor laser with a locked central wavelength of 976nm. The gain fiber 5 uses an ytterbium-doped optical fiber with a fiber size of 10μm / 125μm produced by Nufern, USA. The first single-mode optical fiber 6 and the second single-mode optical fiber 7 are both single-mode optical fibers with a fiber size of 6μm / 125μm and a length of 100m produced by Nufern, USA.
[0025] After the laser light source outputs the injected laser pulse, it passes through the fiber isolator and is coupled into the gain fiber through the (2+1)×1 pump combiner. At the same time, the pump light generated by the pump source is coupled into the gain fiber through the (2+1)×1 pump combiner. After amplification, the injected laser pulse propagates in the direction of the first single-mode fiber, and after receiving the random Rayleigh feedback in the single-mode fiber, it reverses and propagates in the direction of the second single-mode fiber. During the propagation process, the SBS nonlinear threshold effect is reduced by the long first single-mode fiber and the second single-mode fiber, triggering a multi-order SBS process, compressing the 50ns pulse width pulse to hundreds of picoseconds.
[0026] The above is only a specific implementation of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by any technician familiar with the technical field within the technical scope disclosed in the present invention should be included in the protection scope of the present invention.
Claims
1. A pulse width compression device for compressing injected laser pulses using the SBS process, characterized in that: The invention comprises a laser light source (1), an optical fiber isolator (2), an optical fiber combiner (3), at least one pump source (4), a gain optical fiber (5), a first single-mode optical fiber (6) and a second single-mode optical fiber (7), wherein the laser light source (1) is connected to the optical fiber combiner (3) via the optical fiber isolator (2), and the pump source (4) is connected to the optical fiber isolator (2); one end of the first single-mode optical fiber (6) is connected to one end of the gain optical fiber (5), and the other end of the gain optical fiber (5) is connected to the output end of the optical fiber combiner (3); and the input end of the optical fiber combiner (3) is connected to one end of the second single-mode optical fiber (7).
2. The pulse width compression device for compressing injected laser pulses using the SBS process according to claim 1, characterized in that: The pulse width of the laser pulse output by the laser light source (1) is in the nanosecond or microsecond order.
3. The pulse width compression device for compressing injected laser pulses using the SBS process according to claim 1, characterized in that: The optical fiber combiner (3) is a (N+1)×1 type optical fiber combiner; the number of the pump sources (4) is N-1; and N is an integer greater than 1.
4. The pulse width compression device for compressing injected laser pulses using the SBS process according to claim 1, characterized in that: The length of the first single-mode optical fiber (6) is greater than or equal to 1 m.
5. The pulse width compression device for compressing injected laser pulses using the SBS process according to claim 1, characterized in that: The length of the second single-mode optical fiber (7) is greater than or equal to 1 m.
6. The pulse width compression device for compressing injected laser pulses using the SBS process according to claim 1, characterized in that: The other end of the first single-mode optical fiber (6) has a bevel angle, and the bevel angle is 8°.
7. The pulse width compression device for compressing injected laser pulses using the SBS process according to claim 1, characterized in that: The other end of the second single-mode optical fiber (7) has a bevel angle, and the bevel angle is 8°.