A phase-continuous swept fiber laser

Abstract

The utility model relates to the technical field of optical fiber laser, specifically relates to a kind of based on phase continuous sweep frequency optical fiber laser, including shell, the inside one side of shell is fixedly installed with the multimode pump transmitter for emitting laser source, the output end of multimode pump transmitter is provided with phase modulator, the other end of phase modulator is provided with first fiber grating, the one side of first fiber grating away from phase modulator is connected with optical fiber body, the other end of optical fiber body is fixedly connected with second fiber grating, the other side of second fiber grating is fixedly connected with the multimode pump coupler of emission gain rear laser.Compared with prior art, the utility model, by being provided with first fiber grating and second fiber grating cooperate optical resonant cavity, and in optical resonant cavity outer wrapping heat pipe, the frequency of stable optical resonant cavity is ensured the stability of laser output frequency, and optical path length drift caused by heat effect can be reduced.

Description

Technical Field

[0001] This utility model relates to the field of fiber laser technology, and in particular to a phase-continuous frequency sweep fiber laser. Background Technology

[0002] A fiber laser is a type of laser that uses optical fiber as the laser medium. It utilizes the gain medium within the fiber, typically the fiber core doped with rare-earth ions (such as erbium, holmium, and thulium), to excite and amplify optical signals. Compared to traditional lasers, fiber lasers offer advantages such as compactness, high efficiency, and flexibility. A phase-sweeping fiber laser is a laser design whose operating principle involves modulating the phase of the laser beam to continuously sweep across a specific frequency range. This design typically employs specialized components and technologies to achieve laser frequency tuning and sweeping, and is widely used in fields such as optical communication, spectral analysis, and medical imaging.

[0003] Traditional fiber lasers lack efficient frequency selectivity, resulting in a wide spectral distribution of the output light wave, making it difficult to achieve single-frequency output. Furthermore, they are easily affected when achieving single-mode output, and are susceptible to interference from external environmental factors, leading to mode switching or non-single-mode output. At the same time, traditional fiber lasers may be affected by thermal effects, and the optical path length is prone to drift, affecting the output accuracy and stability of the laser. Utility Model Content

[0004] In view of this, the purpose of this utility model is to propose a phase-continuously swept fiber laser to solve the problem of the lack of efficient frequency selectivity in fiber lasers.

[0005] To achieve the above objectives, this utility model provides a phase-continuously sweeping fiber laser, comprising a housing, wherein a multimode pump emitter for emitting laser source is fixedly installed on one side of the housing, a phase modulator is provided at the output end of the multimode pump emitter, a first fiber grating is provided at the other end of the phase modulator, an optical fiber body is connected to the side of the first fiber grating away from the phase modulator, a second fiber grating is fixedly connected to the other end of the optical fiber body, a multimode pump coupler for emitting laser after gain is fixedly connected to the other side of the second fiber grating, and the other end of the multimode pump coupler is connected to an output port;

[0006] The outer side of the optical fiber body is wrapped with a ring-shaped optical resonant cavity. The optical fiber body is a double-clad gain optical fiber. The housing is also equipped with a heat dissipation component for adjusting the temperature of the optical fiber body and the optical resonant cavity. The heat dissipation component includes a heat dissipation pipe and a water inlet and a water outlet located at both ends of the heat dissipation pipe. The water inlet and the water outlet are both disposed through the housing.

[0007] Preferably, the first fiber grating and the second fiber grating are located on opposite sides of the optical resonant cavity.

[0008] Preferably, the first fiber grating is a high-reflectivity grating with a reflectivity R > 99%, and the second fiber grating is a low-reflectivity grating with a reflectivity R < 10%.

[0009] Preferably, the optical resonant cavity is made of silicon dioxide, and two doped optical fibers are disposed on the optical fiber body and extend into the optical resonant cavity.

[0010] Preferably, a section of water inlet pipe is branched off from one side of the water inlet end and is arranged parallel to the water inlet end, a booster pump body is provided at the end of the water inlet end, the water outlet end is set as a water outlet pipe, and the heat dissipation pipe is arranged in a spiral shape and wrapped around the outer surface of the optical resonant cavity.

[0011] Preferably, the top of the housing is provided with a handle, and the bottom of the housing is provided with a base.

[0012] The beneficial effects of this utility model are:

[0013] 1. This phase-continuous frequency-sweeping fiber laser utilizes an optical resonant cavity comprised of a first fiber grating and a second fiber grating, with a heat sink surrounding the cavity. The highly reflective first fiber grating, positioned on one side of the optical resonant cavity, enhances the frequency selectivity of the laser within the cavity. The high reflectivity of the grating reflects most of the laser beam, thus amplifying specific frequency modes within the cavity and improving the laser's single-mode characteristics. Furthermore, the combination of the optical resonant cavity and the high reflectivity of the first fiber grating increases the number of round trips within the cavity, thereby increasing the laser's gain efficiency and ultimately improving the laser's performance. The performance of the laser is enhanced by the low reflectivity of the second fiber grating, which reduces photon loss between the optical resonator and the external environment, preventing laser loss outside the optical resonator and thus reducing photon loss and improving laser output efficiency. Furthermore, by adjusting the reflectivity of the second fiber grating, the intensity and frequency of the output laser can be controlled to adapt to different application requirements. In conjunction with a heat sink, the temperature of the optical resonator and the fiber body can be adjusted, thereby stabilizing the frequency of the optical resonator, ensuring the stability of the laser output frequency, and reducing optical path length drift caused by thermal effects, thus improving the accuracy of the laser.

[0014] 2. This phase-continuous frequency sweep fiber laser utilizes silicon dioxide in the optical resonant cavity and doped fibers in the optical fiber. The relatively high refractive index of silicon dioxide helps to form a highly efficient optical resonant cavity. By using doped fibers, the refractive index of the optical resonant cavity can be controlled to better adapt to lasers within a specific frequency range. Furthermore, the type and concentration of doped fibers can be controlled to form a specific material structure within the optical resonant cavity, thereby enhancing the interaction between the laser and the material. Introducing doped fibers into the optical resonant cavity optimizes its frequency selectivity, making it more suitable for laser resonance conditions, thus improving the single-mode performance of the laser and ensuring stable laser output within a specific frequency range. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only for this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a three-dimensional structural diagram of the present invention;

[0017] Figure 2 This is a schematic diagram of the internal cross-sectional structure of the present invention;

[0018] Figure 3 This is a schematic diagram of the planar structure of this utility model;

[0019] Figure 4 This is a schematic diagram of the working process of this utility model.

[0020] The diagram is marked as follows:

[0021] 1. Housing; 2. Multimode pump transmitter; 3. Phase modulator; 4. First fiber grating; 5. Optical resonant cavity; 6. Fiber body; 7. Second fiber grating; 8. Multimode pump coupler; 9. Water inlet; 10. Water inlet pipe; 11. Heat sink pipe; 12. Water outlet pipe; 13. Doped fiber; 14. Output port; 15. Handle; 16. Base. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to specific embodiments.

[0023] It should be noted that, unless otherwise defined, the technical or scientific terms used in this utility model should have the ordinary meaning understood by one of ordinary skill in the art to which this utility model pertains. The terms "first," "second," and similar terms used in this utility model do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0024] like Figures 1 to 4As shown, a phase-continuous frequency sweep fiber laser includes a housing 1. A multimode pump emitter 2 for emitting laser light is fixedly installed on one side of the housing 1. A phase modulator 3 is located at the output end of the multimode pump emitter 2. A first fiber grating 4 is located at the other end of the phase modulator 3. An optical fiber body 6 is connected to the side of the first fiber grating 4 away from the phase modulator 3. A second fiber grating 7 is fixedly connected to the other end of the optical fiber body 6. A multimode pump coupler 8 for emitting a boosted laser is fixedly connected to the other side of the second fiber grating 7. The other end of the multimode pump coupler 8 is connected to an output port 14. A circular optical resonant cavity 5 is wrapped around the outside of the optical fiber body 6. The optical fiber body 6 is a double-clad gain fiber. A heat dissipation assembly for adjusting the temperature of the optical fiber body 6 and the optical resonant cavity 5 is also provided inside the housing 1. The heat dissipation assembly includes a heat sink 11 and water inlet 9 and water outlet 9 located at both ends of the heat sink 11. Both the water inlet 9 and water outlet 9 penetrate the housing 1. A handle 15 is located at the top of the housing 1, and a... The base 16 houses a multimode pump emitter 2 fixed inside the housing 1, which outputs a pump light source to excite the fiber laser. A phase modulator 3 is located at the output end of the pump light source and is used to achieve continuous phase modulation for frequency sweeping. Then, a first fiber grating 4 is connected to the other end of the phase modulator 3 to introduce the light source into the fiber body 6. A circular optical resonant cavity 5 is wrapped around the outside of the fiber body 6 to improve the laser's gain efficiency and frequency selectivity. At the same time, the fiber body 6 is a double-clad gain fiber, which helps to improve optical performance, especially under high power and high gain conditions. When the laser is in a high gain state, the temperature of the fiber body 6 and the optical resonant cavity can be adjusted by the use of heat dissipation components to maintain the stability of the laser. A second fiber grating 7 is connected to the other end of the fiber body 6 and is connected to a multimode pump coupler 8 that emits the laser with gain, coupling the pump energy into the optical resonant cavity 5 to achieve laser gain. Finally, the gained laser is excited out through the output port 14.

[0025] like Figure 3As shown, the first fiber grating 4 and the second fiber grating 7 are located on opposite sides of the optical resonant cavity 5. The first fiber grating 4 is a high-reflectivity grating with a reflectivity R > 99%, while the second fiber grating 7 is a low-reflectivity grating with a reflectivity R < 10%. The high-reflectivity first fiber grating 4, located on one side of the optical resonant cavity 5, enhances the frequency selectivity of the laser within the optical resonant cavity 5. The high-reflectivity grating reflects most of the laser, thereby enhancing specific frequency modes within the optical resonant cavity 5 and improving the single-mode characteristics of the laser. Simultaneously, the formation of the optical resonant cavity 5, combined with the high reflectivity of the first fiber grating 4, increases the number of round trips of the laser within the optical resonant cavity 5, thereby increasing the laser's gain efficiency and improving the laser's performance. The low-reflectivity second fiber grating 7 reduces photon loss between the optical resonant cavity 5 and the external environment, preventing laser loss outside the optical resonant cavity 5, thus reducing system photon loss and improving laser output efficiency. Furthermore, by adjusting the reflectivity of the second fiber grating 7, the intensity and frequency of the output laser can be controlled to adapt to different application requirements.

[0026] like Figure 2 , Figure 3 As shown, the optical resonant cavity 5 is made of silicon dioxide, and two doped optical fibers 13 are disposed on the optical fiber body 6 and extend into the optical resonant cavity 5. The refractive index of silicon dioxide is relatively high, which helps to form an efficient optical resonant cavity 5. By using doped optical fibers 13, the refractive index of the optical resonant cavity 5 can be adjusted to better adapt to lasers in a specific frequency range. Furthermore, the type and concentration of doped optical fibers 13 can be controlled to form a specific material structure inside the optical resonant cavity 5, thereby enhancing the interaction between the laser and the material. By introducing doped optical fibers 13 into the optical resonant cavity 5, the frequency selectivity of the optical resonant cavity 5 can be optimized to make it more suitable for the resonance conditions of the laser, thereby improving the single-mode performance of the laser and ensuring stable laser output within a specific frequency range.

[0027] like Figure 1As shown, a section of inlet pipe 10 branches off from one side of the inlet end 9 and is arranged parallel to the inlet end 9. A booster pump is installed at the end of the inlet end 9, and the outlet end is set as the outlet pipe 12. The heat dissipation pipe 11 is spirally arranged and wrapped around the outer surface of the optical resonant cavity 5. The coolant enters from the inlet pipe 10 at the inlet end 9 and is pressurized by the booster pump, which drives the coolant to flow in the heat dissipation pipe 11. The spiral arrangement of the heat dissipation pipe 11 and its wrapping around the outer surface of the optical resonant cavity 5 can adjust the temperature of the optical resonant cavity 5 and the fiber body 6. Finally, the coolant flows out from the outlet pipe 12. The spiral arrangement of the heat dissipation pipe 11 and the parallel flow of the fluid make the system more sensitive to temperature changes, which facilitates fine control of the cooling effect according to the system's working state and environmental conditions. By adjusting the flow rate and temperature of the coolant, the temperature of the optical resonator 5 and the fiber body 6 can be adjusted, thereby stabilizing the frequency of the optical resonant cavity 5, ensuring the stability of the laser output frequency, reducing the optical path length drift caused by thermal effects, and improving the accuracy of the laser.

[0028] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of the present invention (including the claims) is limited to these examples; within the framework of the present invention, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of the different aspects of the present invention as described above, which are not provided in the details for the sake of brevity.

[0029] This utility model is intended to cover all such substitutions, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A phase-continuous swept fiber laser based on, comprising a housing (1), characterized in that, A multimode pump emitter (2) for emitting laser source is fixedly installed on one side of the inner side of the housing (1). A phase modulator (3) is provided at the output end of the multimode pump emitter (2). A first fiber grating (4) is provided at the other end of the phase modulator (3). An optical fiber body (6) is connected to the side of the first fiber grating (4) away from the phase modulator (3). A second fiber grating (7) is fixedly connected to the other end of the optical fiber body (6). A multimode pump coupler (8) for emitting laser after gain is fixedly connected to the other side of the second fiber grating (7). The other end of the multimode pump coupler (8) is connected to the output port (14). The outer side of the optical fiber body (6) is wrapped with a circular optical resonant cavity (5). The optical fiber body (6) is a double-clad gain optical fiber. The housing (1) is also provided with a heat dissipation component for adjusting the temperature of the optical fiber body (6) and the optical resonant cavity (5). The heat dissipation component includes a heat dissipation pipe (11) and a water inlet (9) and a water outlet at both ends of the heat dissipation pipe (11). The water inlet (9) and the water outlet are both disposed through the housing (1).

2. The phase-continuous swept fiber laser of claim 1, wherein, The first fiber grating (4) and the second fiber grating (7) are located on both sides of the optical resonant cavity (5).

3. The phase-continuous sweep fiber laser according to claim 2, characterized in that, The first fiber grating (4) is a high reflectivity grating with a reflectivity of R > 99%, and the second fiber grating (7) is a low reflectivity grating with a reflectivity of R < 10%.

4. The phase-continuous frequency sweep fiber laser according to claim 1, characterized in that, The optical resonant cavity (5) is made of silicon dioxide, and two doped optical fibers (13) are provided on the optical fiber body (6) and extend into the optical resonant cavity (5).

5. The phase-continuous frequency sweep fiber laser according to claim 1, characterized in that, A section of water inlet pipe (10) is branched off from one side of the water inlet end (9) and is set parallel to the water inlet end (9). A booster pump body is provided at the end of the water inlet end (9). The water outlet end is set as a water outlet pipe (12). The heat dissipation pipe (11) is arranged in a spiral shape and wrapped around the outer surface of the optical resonant cavity (5).

6. The phase-continuous sweep fiber laser according to claim 1, characterized in that, The top of the housing (1) is provided with a handle (15), and the bottom of the housing (1) is provided with a base (16).

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