Chirp grating spectrum shaping device, method, equipment, storage medium and product

Abstract

The invention discloses a chirp grating spectrum shaping device and method, equipment, a storage medium and a product, and relates to the technical field of optical fibers. The small-hole diaphragm is arranged on an output light path of the laser and is used for filtering stray light of light spots; the reflecting mirror is arranged on the light emitting side of the small-hole diaphragm and is used for reflecting light rays; the linear displacement table is arranged on the supporting reflecting mirror, and the linear displacement table can move in the axial direction of the grating area; the cylindrical mirror is arranged on a reflex light path behind the reflecting mirror and is used for compressing the circular light spot into an elliptical light spot; the phase mask plate is arranged on the light emitting side of the cylindrical mirror and is used for forming a grating spectrum shape on the optical fiber core; and the control unit is electrically connected with the linear displacement table and is used for controlling the movement track of the linear displacement table so as to adjust the exposure doses at different positions of the grating region to realize chirp grating spectrum shape control. The optical fiber laser can adapt to different service scenes by adjusting the spectral shape of the grating.

Description

Technical Field

[0001] The present application relates to the field of optical fiber technology, and in particular to a chirped grating spectrum shaping device, method, equipment, storage medium and product. Background Art

[0002] The spectral shape of the chirped grating can be designed according to specific needs to meet the optical performance requirements in different business scenarios, thus being widely used.

[0003] Currently, when a chirped grating is used as the cavity mirror grating of a fiber laser, its spectral shape is usually fixed, making it difficult to flexibly adjust the spectral shape according to different business scenarios, resulting in the fiber laser being unable to achieve the expected working effect.

[0004] In summary, how to adjust the spectral shape of the grating so that the fiber laser can adapt to different business scenarios has become a technical problem that needs to be solved urgently in this field. Summary of the Invention

[0005] The main purpose of this application is to provide a chirped grating spectrum shaping device, method, equipment, storage medium and product, aiming to enable the fiber laser to adapt to different business scenarios by adjusting the spectral shape of the grating.

[0006] To achieve the above objectives, the present application proposes a chirped grating spectrum shaping device, which includes:

[0007] A laser, for outputting laser light;

[0008] A small aperture diaphragm is provided in the output optical path of the laser to filter out stray light from the light spot;

[0009] A reflector, disposed on the light-emitting side of the pinhole aperture, for refracting light;

[0010] A linear translation stage is provided to support the reflector, and the linear translation stage can move along the axial direction of the grating area;

[0011] A cylindrical mirror is provided in the folding light path after the reflector, and is used to compress the circular light spot into an elliptical light spot;

[0012] A phase mask is provided on the light-emitting side of the cylindrical mirror and is used to form a grating spectrum shape in the optical fiber core;

[0013] A control unit is electrically connected to the linear translation stage and is used to control the movement trajectory of the linear translation stage to adjust the exposure dose at different positions of the grating region to achieve chirped grating spectrum shape control.

[0014] In one embodiment, the control unit is further configured to:

[0015] Analyze the target spectral function to obtain the grating structure parameters;

[0016] axially layering the grating region into a plurality of sub-regions with uniform periods based on the grating structure parameters;

[0017] Calculating the exposure dose corresponding to each sub-gate region;

[0018] A movement control parameter for controlling the movement trajectory of the linear translation stage is generated according to the exposure dose.

[0019] In one embodiment, the target spectral function is a Gaussian spectral function or a triangular spectral function, and the exposure dose distribution of the grating region matches the target spectral function.

[0020] In one embodiment, the control unit is further configured to:

[0021] The linear translation stage is controlled to move along the axial direction of the grating region according to the movement control parameter to adjust the exposure dose at different positions of the grating region so that the chirped grating spectrum shape matches the target spectrum function.

[0022] In addition, to achieve the above-mentioned objectives, the present application also proposes a chirped grating spectrum shaping method, which is applied to the control unit in the chirped grating spectrum shaping device as described above. The chirped grating spectrum shaping method includes:

[0023] Analyze the target spectral function to obtain the grating structure parameters;

[0024] axially layering the grating region into a plurality of sub-regions with uniform periods based on the grating structure parameters;

[0025] Calculating the exposure dose corresponding to each sub-gate region;

[0026] A movement control parameter for controlling the movement trajectory of the linear translation stage is generated according to the exposure dose.

[0027] In one embodiment, the step of calculating the exposure dose corresponding to each sub-gate region includes:

[0028] For each layer of the sub-gate region, the exposure dose required for the sub-gate region is calculated according to a mapping relationship between the refractive index modulation depth of the sub-gate region and the exposure dose.

[0029] In one embodiment, the step of calculating the exposure dose corresponding to each sub-gate region includes:

[0030] For each layer of the sub-gate region, the exposure dose required for the sub-gate region is calculated according to a mapping relationship between the reflection coefficient of the sub-gate region and the exposure dose.

[0031] In addition, to achieve the above-mentioned purpose, the present application also proposes an electronic device, which includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the computer program is configured to implement the steps of the chirped grating spectrum shaping method as described above.

[0032] In addition, to achieve the above-mentioned purpose, the present application also proposes a storage medium, which is a computer-readable storage medium and stores a computer program. When the computer program is executed by a processor, the steps of the chirped grating spectrum shaping method as described above are implemented.

[0033] In addition, to achieve the above-mentioned purpose, the present application also provides a computer program product, which includes a computer program. When the computer program is executed by a processor, the steps of chirped grating spectrum shaping as described above are implemented.

[0034] The present application proposes a chirped grating spectrum shaping device, which includes: a laser for outputting laser light; a pinhole aperture, arranged in the laser output light path, for filtering out stray light from the light spot; a reflector, arranged on the light output side of the pinhole aperture, for refracting light; a linear translation stage, arranged to support the reflector, and the linear translation stage can move axially along the grating region; a cylindrical mirror, arranged in the refracting light path after the reflector, for compressing the circular light spot into an elliptical light spot; a phase mask, arranged on the light output side of the cylindrical mirror, for forming a grating spectrum shape in the optical fiber core; a control unit, electrically connected to the linear translation stage, for controlling the movement trajectory of the linear translation stage, so as to adjust the exposure dose at different positions of the grating region to realize the control of the chirped grating spectrum shape.

[0035] In summary, the chirped grating spectrum shaping device proposed in this application realizes precise control of the exposure dose at different positions of the grating area by introducing a linear translation stage and a control unit. Specifically, by controlling the movement trajectory of the linear translation stage, the exposure dose at different positions of the grating area can be flexibly adjusted, thereby realizing flexible adjustment of the chirped grating spectrum shape. This flexible adjustment capability enables the fiber laser to adjust the spectrum shape according to the needs of different business scenarios, thereby achieving the expected working effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0037] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0038] Figure 1 A schematic diagram of the device structure provided for the chirped grating spectrum shaping device embodiment 1 of the present application;

[0039] Figure 2 A schematic diagram of the flow chart of the second embodiment of the chirped grating spectrum shaping method of the present application;

[0040] Figure 3 Schematic diagram of exposure dose distribution provided for Example 2 of the chirped grating spectrum shaping method of this application;

[0041] Figure 4 Schematic diagram of the movement speed function of the translation stage provided in Example 2 of the chirped grating spectrum shaping method of this application;

[0042] Figure 5 Schematic diagram of matching the output spectrum and target spectrum function provided in Example 2 of the chirped grating spectrum shaping method of this application;

[0043] Figure 6 Another schematic diagram of matching the output spectrum with the target spectrum function provided in Example 2 of the chirped grating spectrum shaping method of this application;

[0044] Figure 7 Schematic diagram of the device structure of the hardware operating environment involved in the chirped grating spectrum shaping method in the embodiment of the present application.

[0045] Figure 1 Description of Figure Numbers:

[0046] Label name Label name 10 laser 20 Aperture diaphragm 30 reflector 40 Linear Translation Stage 50 Cylindrical mirror 60 Phase mask 70 Controller

[0047] The purpose, features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0048] It should be understood that the specific embodiments described herein are merely used to explain the technical solutions of the present application and are not intended to limit the present application.

[0049] The spectral shape of the chirped grating can be designed according to specific needs to meet the optical performance requirements in different business scenarios, thus being widely used.

[0050] Currently, when a chirped grating is used as the cavity mirror grating of a fiber laser, its spectral shape is usually fixed, making it difficult to flexibly adjust the spectral shape according to different business scenarios, resulting in the fiber laser being unable to achieve the expected working effect.

[0051] In summary, how to adjust the spectral shape of the grating so that the fiber laser can adapt to different business scenarios has become a technical problem that needs to be solved urgently in this field.

[0052] An embodiment of the present application provides a solution, proposing a chirped grating spectrum shaping device, which includes: a laser for outputting laser light; a pinhole aperture, arranged in the laser output light path, for filtering out stray light from the light spot; a reflector, arranged on the light output side of the pinhole aperture, for refracting light; a linear translation stage, arranged to support the reflector, and the linear translation stage can move axially along the grating region; a cylindrical mirror, arranged in the refracting light path after the reflector, for compressing the circular light spot into an elliptical light spot; a phase mask, arranged on the light output side of the cylindrical mirror, for forming a grating spectrum shape in the optical fiber core; a control unit, electrically connected to the linear translation stage, for controlling the movement trajectory of the linear translation stage, so as to adjust the exposure dose at different positions of the grating region to realize the control of the chirped grating spectrum shape.

[0053] In summary, the chirped grating spectrum shaping device proposed in the embodiment of the present application realizes precise control of the exposure dose at different positions of the grating area by introducing a linear translation stage and a control unit. Specifically, by controlling the movement trajectory of the linear translation stage, the exposure dose at different positions of the grating area can be flexibly adjusted, thereby realizing flexible adjustment of the chirped grating spectrum shape. This flexible adjustment capability enables the fiber laser to adjust the spectrum shape according to the needs of different business scenarios, thereby achieving the expected working effect.

[0054] Based on this, the embodiment of the present application provides a chirped grating spectrum shaping device, referring to Figure 1 , Figure 1 This is a structural diagram of the first embodiment of the chirped grating spectrum shaping device of the present application.

[0055] In this embodiment, the chirped grating spectrum shaping device includes:

[0056] A laser 10, configured to output laser light;

[0057] A pinhole diaphragm 20 is provided in the output optical path of the laser 10 to filter out stray light from the light spot;

[0058] The reflector 30 is provided on the light-emitting side of the aperture diaphragm 20 and is used to refract the light;

[0059] A linear translation stage 40 is disposed on the supporting reflector 30 and is movable along the axial direction of the grating region;

[0060] The cylindrical mirror 50 is provided in the folding light path after the reflector 30 and is used to compress the circular light spot into an elliptical light spot;

[0061] A phase mask is provided on the light-emitting side of the cylindrical mirror 50 and is used to form a grating spectrum shape in the optical fiber core;

[0062] The control unit is electrically connected to the linear translation stage 40 and is used to control the movement trajectory of the linear translation stage 40 to adjust the exposure dose at different positions of the grating region to achieve the control of the chirped grating spectrum shape.

[0063] In this embodiment, the laser 10 serves as the light source of the device. Its main function is to output stable laser light, which will serve as the basic beam for subsequent spectrum shaping operations. Its performance directly affects the final spectrum shaping effect.

[0064] A pinhole diaphragm 20 is positioned in the output optical path of the laser 10 to filter out stray light from the light spot emitted by the laser 10. The presence of stray light can interfere with the subsequent spectrum shaping process, reducing the accuracy and quality of the spectrum shaping. The pinhole diaphragm 20's screening ensures a high degree of purity of the light beam entering the subsequent optical system, thus ensuring high-quality spectrum shaping.

[0065] Reflector 30 is positioned on the light-exiting side of aperture 20. Its primary function is to deflect light. Reflection by reflector 30 changes the direction of the light beam, allowing it to follow a predetermined optical path and enter subsequent optical components. In this embodiment, reflector 30 is preferably a 45° reflector, achieving a 90° deflection of the light beam.

[0066] The linear translation stage 40 is used to support the reflector 30 and has the ability to move along the axial direction of the grating area. By controlling the movement of the linear translation stage 40, the position of the reflector 30 can be precisely adjusted, thereby changing the irradiation position of the light beam on the grating area.

[0067] Cylindrical mirror 50 is placed in the deflecting optical path after reflector 30. Its main function is to compress the circular light spot after being deflected by reflector 30 into an elliptical spot. This adjustment of the light spot shape is to better meet the requirements of the subsequent phase mask template for the beam. By changing the light spot shape, the interference fringes formed by the light beam in the fiber core can be optimized, thereby improving the quality of the grating spectrum.

[0068] The phase mask is located on the light-exiting side of the cylindrical mirror 50. Its core function is to form a grating spectrum in the fiber core. When the light beam, adjusted by the cylindrical mirror 50, strikes the phase mask, it produces ±1st-order diffracted light. These diffracted lights form interference fringes in the fiber core, ultimately forming a grating spectrum with a specific shape.

[0069] The control unit is electrically connected to the linear translation stage 40. Its primary function is to control the trajectory of the linear translation stage 40. By precisely controlling parameters such as the linear translation stage 40's speed, acceleration, and direction, the exposure dose at different locations within the grating region can be precisely adjusted. Through precise control by the control unit, the exposure dose distribution within the grating region can be flexibly adjusted according to the preset target spectral shape, thereby achieving precise control of the chirped grating's spectral shape, enabling it to meet the spectral shape requirements of different application scenarios.

[0070] In a feasible embodiment, the control unit is further configured to:

[0071] Analyze the target spectral function to obtain the grating structure parameters;

[0072] The grating region is axially divided into a plurality of sub-grating regions with uniform periods based on the grating structure parameters;

[0073] Calculate the exposure dose corresponding to each sub-gate area;

[0074] The movement control parameters for controlling the movement trajectory of the linear translation stage 40 are generated according to the exposure dose.

[0075] It's important to note that the target spectral function (TSF) describes the desired spectral shape. It defines the intensity distribution of the spectrum at different wavelengths and serves as the goal and basis for spectral shaping. In chirped grating spectral shaping, analyzing the TSF allows us to determine the grating's structural parameters, enabling precise control of the grating's spectral shape to meet specific application requirements.

[0076] For example, if the spectrum needs to be shaped into a Gaussian shape, the target spectrum function can be a Gaussian function, whose mathematical expression is:

[0077]

[0078] Where R(λ,z) ​​represents the reflectivity or spectral intensity at wavelength λ and position z; λ represents the wavelength of light; 1080 represents the center wavelength of the spectrum; C represents the chirp rate, which describes the rate of change of the grating period along the fiber axis; L represents the length of the grating; and exp represents an exponential function.

[0079] It should also be noted that the chirp rate represents the rate of change of the grating period along the fiber axis. The period of a linearly chirped grating changes linearly along the fiber axis, and its period can be expressed as:

[0080]

[0081] Where Λ0 is the grating period at the center of the linear chirped Bragg grating, z is the position along the fiber axis, and d is the length of the grating.

[0082] In this embodiment, the control unit extracts parameter information related to the grating structure by mathematically analyzing and parsing the target spectral function. These parameters include the grating region length, chirp rate, and central period. This parsing process typically involves Fourier transforming, inverse transforming, or other mathematical processing methods on the target spectral function to extract the grating structure parameters. These grating structure parameters directly determine the physical properties of the grating at different positions and the resulting spectral shape.

[0083] Then, based on the analytically derived grating structure parameters, the grating region is layered along the axial direction into multiple sub-regions with uniform period. Each sub-region can be considered an independent grating unit with uniform period. This layering method enables individual exposure dose control for each sub-region, thereby achieving precise adjustment of the overall grating spectral shape.

[0084] Among them, the layering process usually determines the number of sub-regions and the length of each sub-region based on the grating region length and the fineness of the target spectrum. The period of each sub-region can be calculated from the overall grating structure parameters by interpolation or other mathematical methods.

[0085] Exposure dose refers to the total amount of light energy each sub-region receives during the grating manufacturing process. By accurately calculating the exposure dose for each sub-region, we can ensure that the refractive index modulation depth or reflectance of each sub-region meets the design requirements, thereby achieving the target spectral shape. Exposure dose calculation can be based on the grating's physical properties (such as the relationship between refractive index modulation depth and exposure dose) and the target spectral function.

[0086] Based on the calculated exposure dose for each sub-region, motion control parameters are generated to control the movement trajectory of the linear translation stage 40. These motion control parameters include the velocity, acceleration, and acceleration direction of the linear translation stage 40 at different positions within the grating region, as well as the step size and wait time of the linear translation stage. By precisely controlling the movement of the linear translation stage 40, each sub-region receives an accurately calculated exposure dose, thereby achieving the goal of spectral shaping.

[0087] In a feasible embodiment, the target spectral function is a Gaussian spectral function or a triangular spectral function, and the exposure dose distribution of the grating region matches the target spectral function.

[0088] In this embodiment, the target spectral function may be a Gaussian shape or a triangular shape, and the exposure dose distribution of the grating region is controlled to achieve matching between the exposure dose distribution of the grating region and the target spectral function.

[0089] For example, taking the Gaussian shape target spectrum function as an example, the target spectrum function is defined as The target spectral function is analyzed to obtain structural parameters such as central wavelength, bandwidth, and chirp rate. The grating region length L is divided into N layers, each with a length of Δz = L / N. The exposure dose of each sub-region is calculated: For a Gaussian spectrum, the exposure dose D(z) can be expressed as: D(z) = P·t(z), where P is the power and t(z) is the exposure time at position z. The exposure time t(z) can be calculated from the target spectral function and the grating structural parameters: Where λ(z) is the wavelength at position z, which can be calculated from the chirp rate C and the gate length L. Based on the exposure dose D(z), the moving speed v(z) of the linear translation stage 40 is calculated as: Wherein, η is the photosensitivity of the grating material; finally, the linear translation stage 40 is controlled to move according to the calculated moving speed v(z).

[0090] Therefore, by precisely controlling the exposure dose, the spectral shape of the chirped grating can be precisely controlled to make it conform to the target spectral function.

[0091] In a feasible embodiment, the control unit is further configured to:

[0092] The linear translation stage 40 is controlled to move along the axial direction of the grating region according to the movement control parameters to adjust the exposure dose at different positions of the grating region so that the chirped grating spectrum shape matches the target spectrum function.

[0093] In this embodiment, the control unit controls the linear translation stage 40 to move along the axial direction of the grating area according to the movement control parameters calculated by the button to ensure that each sub-area receives a precisely calculated exposure dose, thereby making the spectral shape of the generated chirped grating match the preset target spectral function.

[0094] In addition, the control unit can also monitor the movement status of the linear translation stage 40 and the exposure status of the grating area in real time, and timely adjust the movement trajectory of the linear translation stage 40 to deal with any deviation or error, ensuring that the final spectral shape accurately meets the target spectral function.

[0095] Thus, in the embodiment of the present application, the chirped grating spectrum shaping device realizes precise control of the exposure dose at different positions of the grating region by introducing the linear translation stage 40 and the control unit. Specifically, by controlling the movement trajectory of the linear translation stage 40, the exposure dose at different positions of the grating region can be flexibly adjusted, thereby realizing flexible adjustment of the chirped grating spectrum shape. This flexible adjustment capability enables the fiber laser 10 to adjust the spectrum shape according to the needs of different business scenarios, thereby achieving the expected working effect.

[0096] Based on the first embodiment of the present application, in the second embodiment of the present application, the same or similar contents as those in the above-mentioned embodiment 1 can be referred to the above introduction and will not be described in detail later. Figure 2 As shown, Figure 2 Schematic diagram of the flow of an embodiment of the chirped grating spectrum shaping method of the present application.

[0097] In this embodiment, the chirped grating spectrum shaping method is applied to the control unit in the chirped grating spectrum shaping device in the first embodiment. The chirped grating spectrum shaping method includes steps S10 to S40:

[0098] Step S10, analyzing the target spectrum function to obtain grating structure parameters;

[0099] It's important to note that the target spectral function (TSF) describes the desired spectral shape. It defines the intensity distribution of the spectrum at different wavelengths and serves as the goal and basis for spectral shaping. In chirped grating spectral shaping, analyzing the TSF allows us to determine the grating's structural parameters, enabling precise control of the grating's spectral shape to meet specific application requirements.

[0100] For chirped gratings, especially linear chirped Bragg gratings, the relationship between the grating period and the fiber axial distance z is described by a mathematical expression based on the characteristic that its period varies linearly along the fiber axis, namely: Where Λ0 is the grating period at the center of the linear chirped Bragg grating, z is the position along the fiber axis, and d is the length of the grating.

[0101] Then, according to the resonance condition of the linearly chirped Bragg grating: Where m is the diffraction order, is the effective refractive index of the fiber core mode, and the resonant center wavelength at different axial positions z is analyzed, and then it is determined that the total reflection spectrum of the grating is the superposition of grating spectra of different periods at each position.

[0102] Thus, the structural parameters of the grating are extracted, including the grating length L, the chirp rate C, and the center period Λ.

[0103] Step S20, axially layering the grating region into a plurality of sub-regions with uniform periods based on the grating structure parameters;

[0104] Based on the acquired grating structure parameters, the grating region is divided into multiple (set to N) sub-regions with uniform period along the axial direction. When N is large enough, each sub-region can be approximately regarded as a Bragg grating with uniform period. Such layered processing helps to accurately control the refractive index modulation depth and reflectivity of each sub-region.

[0105] Step S30, calculating the exposure dose corresponding to each sub-gate region;

[0106] For each sub-gate region, the required exposure dose is calculated according to its desired peak reflectivity and bandwidth requirements and by utilizing the proportional relationship between the refractive index modulation depth or the reflection coefficient and the exposure dose.

[0107] Specifically, for each sub-region i (i=1, 2, ..., N), the exposure dose Ei=k·Ri, where k is a proportional constant related to the grating material and manufacturing process, and Ri is the expected peak reflectivity of the sub-region i, which can be determined based on the value of the target spectral function at the corresponding axial position of the sub-region.

[0108] Step S40 : generating movement control parameters for controlling the movement trajectory of the linear translation stage according to the exposure dose.

[0109] The calculated exposure doses for each sub-region are converted into parameters for controlling the movement trajectory of the linear translation stage. Specifically, a relationship between the exposure dose and the dwell time or movement speed of the linear translation stage in each sub-region can be established.

[0110] Since the linear translation stage needs to move between different sub-grid areas and control the exposure dose by adjusting the speed or dwell time, the movement speed of the linear translation stage in each sub-grid area can be set to vi = Δz / ti, where ti is proportional to the exposure dose. That is, the greater the exposure dose required by the sub-grid area, the slower the movement speed of the linear translation stage in the sub-grid area, or the longer the dwell time, to ensure sufficient exposure.

[0111] Furthermore, the movement speed or dwell time parameters of all sub-grating areas are integrated to form a complete movement trajectory control sequence of the linear translation stage. This movement trajectory control sequence can be implemented through programming to accurately control the movement of the linear translation stage during the grating production process, thereby realizing the grating spectrum shape control of the target spectral function.

[0112] In a feasible embodiment, step S30 may include step S301:

[0113] Step S301 : For each layer of sub-gate regions, the exposure dose required for the sub-gate regions is calculated according to a mapping relationship between the refractive index modulation depth of the sub-gate regions and the exposure dose.

[0114] For each layered sub-grating area, the desired refractive index modulation depth of the sub-grating area is first determined. The refractive index modulation depth is an important parameter that describes the grating's ability to modulate the phase of light waves. It directly affects the grating's reflection and transmission characteristics. Based on the theoretical and experimental data of grating production, a mapping relationship between the refractive index modulation depth and the required exposure dose is established.

[0115] For each sub-region i (i=1, 2, ..., N), the established mapping relationship is used to calculate the exposure dose required to achieve the desired refractive index modulation depth Δni. This mathematical expression can be expressed as: Ei=f(Δni), where f represents the mapping function between refractive index modulation depth and exposure dose. This step accurately determines the exposure dose required for each sub-region to achieve the desired optical performance.

[0116] In a feasible embodiment, step S30 may include step S302:

[0117] Step S302 : For each layer of sub-gate regions, the exposure dose required for the sub-gate regions is calculated according to a mapping relationship between the reflection coefficient of the sub-gate regions and the exposure dose.

[0118] For each layered sub-grating area, the reflection coefficient is an important indicator to measure the reflective ability of the grating. It determines the reflection efficiency of the grating at a specific wavelength. Based on the theoretical and experimental data of grating production, a mapping relationship between the reflection coefficient and the required exposure dose is established.

[0119] For each sub-gate region i (i=1, 2, ..., N), according to its desired reflection coefficient Ri, the exposure dose required to achieve the reflection coefficient is calculated using the established mapping relationship. The mathematical expression can be expressed as: Ei′=g(Ri), where g represents the mapping function between the reflection coefficient and the exposure dose.

[0120] In actual operation, the final exposure dose can be determined based on specific needs and grating performance requirements by comprehensively considering the two parameters of refractive index modulation depth and reflection coefficient.

[0121] In summary, in this embodiment, the chirped grating spectrum shaping device achieves precise control of the exposure dose at different positions of the grating area by introducing a linear translation stage and a control unit. Specifically, by controlling the movement trajectory of the linear translation stage, the exposure dose at different positions of the grating area can be flexibly adjusted, thereby achieving flexible adjustment of the chirped grating spectrum shape. This flexible adjustment capability enables the fiber laser to adjust the spectrum shape according to the needs of different business scenarios, thereby achieving the expected working effect.

[0122] For example, to help understand the implementation process of the chirped grating spectrum shaping method obtained by combining this embodiment with the above embodiment 1, please refer to Figures 3 to 6 , specifically:

[0123] In the chirped grating spectrum shaping scheme, the control unit calculates the exposure dose required for each sub-grating area according to the target spectrum function. Figure 3This is a schematic diagram of the exposure dose distribution of the chirped grating. The exposure amount at each position in the grating area is proportional to the spectral shape represented by the target spectral function.

[0124] Then, the movement control parameters for controlling the movement trajectory of the linear translation stage are generated according to these exposure doses. In a feasible implementation scenario, the movement control parameters include the movement speed of the linear translation stage at different positions of the grating area, such as Figure 4 As shown in the figure, the horizontal axis Length represents the length of the grating region, which is the distance the linear translation stage moves. The vertical axis Velocity represents the moving speed of the linear translation stage. The dotted line represents the functional relationship between the speed of the linear translation stage and the change of the grating region length. That is, during the spectrum shaping process, the speed of the linear translation stage is changed to achieve different exposure doses at different positions, thereby generating a chirped grating with a specific spectral shape (such as a Gaussian shape or a triangular shape).

[0125] The target spectral function may be a Gaussian spectral function or a triangular spectral function. For example, Figure 5 This figure shows how the output spectrum of the chirped grating spectrum shaping device matches the target spectral function. The horizontal axis represents wavelength, and the vertical axis represents the intensity of the output spectrum. The top flat curve in the figure represents the output spectrum after chirped grating shaping, while curves Gauss 1 and Gauss 2 represent Gaussian-shaped target spectral functions. Ideally, the top flat curve should be as close as possible to the selected target spectral function to achieve the best spectral shaping effect.

[0126] Figure 6 This figure shows another example of how the output spectrum of the chirped grating spectrum shaping device matches the target spectral function. The horizontal axis represents wavelength, and the vertical axis represents the intensity of the output spectrum. The top flat curve in the figure represents the output spectrum after chirped grating shaping. The Gauss curve and the Triangle curve represent the Gaussian and triangular target spectral functions, respectively. Ideally, the top flat curve should be as close as possible to the selected target spectral function to achieve the best spectral shaping effect.

[0127] It should be noted that the above examples are only used to understand the present application and do not constitute a limitation on the chirped grating spectrum shaping method of the present application. More simple transformations based on this technical concept are all within the scope of protection of the present application.

[0128] An embodiment of the present application provides an electronic device, comprising: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can perform the chirped grating spectrum shaping method of the above-mentioned embodiment 1.

[0129] Reference below Figure 7 , which shows a schematic diagram of the structure of an electronic device suitable for implementing the embodiments of the present application. The electronic devices in the embodiments of the present application may include, but are not limited to, mobile terminals such as laptop computers, digital broadcast receivers, PDAs (Personal Digital Assistants), PADs (Portable Application Descriptions), PMPs (Portable Media Players), in-vehicle terminals (such as in-vehicle navigation terminals), and fixed terminals such as digital TVs and desktop computers. Figure 7 The electronic device shown is merely an example and should not limit the functions and scope of use of the embodiments of the present application.

[0130] like Figure 7 As shown, the electronic device may include a processing device 1001 (e.g., a central processing unit, a graphics processing unit, etc.), which can perform various appropriate actions and processes based on programs stored in a read-only memory 1002 or programs loaded from a storage device 1003 into a random access memory 1004. The random access memory 1004 also stores various programs and data required for the operation of the electronic device. The processing device 1001, the read-only memory 1002, and the random access memory 1004 are connected to each other via a bus 1005. An input / output interface 1006 is also connected to the bus. Typically, the following systems may be connected to the input / output interface 1006: an input device 1007 including, for example, a touch screen, a touchpad, a keyboard, a mouse, an image sensor, a microphone, an accelerometer, a gyroscope, etc.; an output device 1008 including, for example, a liquid crystal display (LCD), a speaker, a vibrator, etc.; a storage device 1003 including, for example, a magnetic tape or a hard disk; and a communication device 1009. The communication device 1009 may allow the electronic device to communicate with other devices wirelessly or wired to exchange data. Although the figures show electronic devices with various systems, it should be understood that it is not required to implement or have all the systems shown. More or fewer systems may be implemented or have instead.

[0131] In particular, according to the embodiments disclosed in the present application, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, the embodiments disclosed in the present application include a computer program product comprising a computer program carried on a computer-readable medium, the computer program comprising program code for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network via a communication device, or installed from a storage device 1003, or installed from a read-only memory 1002. When the computer program is executed by the processing device 1001, the above-mentioned functions defined in the method of the embodiment disclosed in the present application are performed.

[0132] The electronic device provided in the embodiments of the present application utilizes the chirped grating spectrum shaping method described in the above embodiments, enabling the fiber laser to adapt to different service scenarios by adjusting the grating's spectral shape. Compared to the prior art, the electronic device provided in the embodiments of the present application achieves the same beneficial effects as the chirped grating spectrum shaping method described in the above embodiments. Other technical features of the electronic device are the same as those disclosed in the chirped grating spectrum shaping method described in the above embodiments and are not further detailed here.

[0133] It should be understood that the various parts disclosed in the embodiments of the present application can be implemented using hardware, software, firmware, or a combination thereof. In the description of the above embodiments, specific features, structures, materials, or characteristics can be combined in any appropriate manner in any one or more embodiments or examples.

[0134] The above are only specific embodiments of the present application, but the scope of protection of this application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

[0135] An embodiment of the present application provides a computer-readable storage medium having computer-readable program instructions (ie, a computer program) stored thereon, wherein the computer-readable program instructions are used to execute the chirped grating spectrum shaping method in the above embodiment.

[0136] The computer-readable storage medium provided in the embodiments of the present application may be, for example, a USB flash drive, but is not limited to electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems or devices, or any combination thereof. More specific examples of computer-readable storage media may include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof. In this embodiment, the computer-readable storage medium may be any tangible medium that contains or stores a program that can be used by or in conjunction with an instruction execution system or device. The program code contained on the computer-readable storage medium may be transmitted using any appropriate medium, including but not limited to: wires, optical cables, RF (Radio Frequency), etc., or any suitable combination thereof.

[0137] The computer-readable storage medium may be included in the electronic device, or may exist independently without being incorporated into the electronic device.

[0138] The computer-readable storage medium carries one or more programs. When the one or more programs are executed by an electronic device, the electronic device: analyzes the target spectral function to obtain grating structure parameters; axially layers the grating region into multiple sub-regions with uniform periods based on the grating structure parameters; calculates the exposure dose corresponding to each layer of sub-regions; and generates movement control parameters for controlling the movement trajectory of the linear translation stage based on the exposure dose.

[0139] The computer program code for performing the operations of the embodiments of the present application can be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, C++, and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code can be executed entirely on the user's computer, partially on the user's computer, as a separate software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving a remote computer, the remote computer can be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or can be connected to an external computer (for example, using an Internet service provider to connect via the Internet).

[0140] The flow charts and block diagrams in the accompanying drawings illustrate the possible architecture, functions and operations of the systems, methods and computer program products according to various embodiments of the present application. In this regard, each box in the flow chart or block diagram can represent a module, program segment or a part of code, and the module, program segment or a part of code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a different order than that marked in the accompanying drawings. For example, two boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram and / or flow chart, and the combination of the boxes in the block diagram and / or flow chart can be implemented by a dedicated hardware-based system that performs the specified function or operation, or can be implemented by a combination of dedicated hardware and computer instructions.

[0141] The modules described in the embodiments of the present application may be implemented in software or hardware, wherein the name of a module does not necessarily limit the unit itself.

[0142] The computer-readable storage medium provided in the embodiments of this application is a computer-readable storage medium that stores computer-readable program instructions (i.e., a computer program) for executing the chirped grating spectrum shaping method described above. This computer-readable storage medium can adapt the fiber laser to different service scenarios by adjusting the grating's spectral shape. Compared to the prior art, the computer-readable storage medium provided in the embodiments of this application has the same beneficial effects as the chirped grating spectrum shaping method provided in the aforementioned embodiments, and will not be further elaborated here.

[0143] The above are only some embodiments of the present application and are not intended to limit the patent scope of the present application. All equivalent structural transformations made using the contents of the present application specification and drawings under the technical concept of the present application, or direct / indirect application in other related technical fields are included in the patent protection scope of the present application.

Claims

1. A chirped grating spectrum shaping device, characterized in that: The chirped grating spectrum shaping device comprises: A laser, for outputting laser light; A small aperture diaphragm is provided in the output optical path of the laser to filter out stray light from the light spot; A reflector, disposed on the light-emitting side of the pinhole aperture, for refracting light; A linear translation stage is provided to support the reflector, and the linear translation stage can move along the axial direction of the grating area; A cylindrical mirror is provided in the folding light path after the reflector, and is used to compress the circular light spot into an elliptical light spot; A phase mask is provided on the light-emitting side of the cylindrical mirror and is used to form a grating spectrum shape in the optical fiber core; A control unit is electrically connected to the linear translation stage and is used to control the movement trajectory of the linear translation stage to adjust the exposure dose at different positions of the grating region to achieve chirped grating spectrum shape control.

2. The chirped grating spectrum shaping device according to claim 1, wherein: The control unit is further configured to: Analyze the target spectral function to obtain the grating structure parameters; axially layering the grating region into a plurality of sub-regions with uniform periods based on the grating structure parameters; Calculating the exposure dose corresponding to each sub-gate region; A movement control parameter for controlling the movement trajectory of the linear translation stage is generated according to the exposure dose.

3. The chirped grating spectrum shaping device according to claim 2, wherein: The target spectral function is a Gaussian spectral function or a triangular spectral function, and the exposure dose distribution of the grating region matches the target spectral function.

4. The chirped grating spectrum shaping device according to claim 2, wherein: The control unit is further configured to: The linear translation stage is controlled to move along the axial direction of the grating region according to the movement control parameter to adjust the exposure dose at different positions of the grating region so that the chirped grating spectrum shape matches the target spectrum function.

5. A chirped grating spectrum shaping method, characterized in that: A control unit applied to the chirped grating spectrum shaping device according to any one of claims 1 to 4, wherein the chirped grating spectrum shaping method comprises: Analyze the target spectral function to obtain the grating structure parameters; axially dividing the grating region into a plurality of sub-regions with uniform periods based on the grating structure parameters; Calculating the exposure dose corresponding to each sub-gate region; A movement control parameter for controlling the movement trajectory of the linear translation stage is generated according to the exposure dose.

6. The chirped grating spectrum shaping method according to claim 5, wherein: The step of calculating the exposure dose corresponding to each sub-gate region includes: For each layer of the sub-gate region, the exposure dose required for the sub-gate region is calculated according to a mapping relationship between the refractive index modulation depth of the sub-gate region and the exposure dose.

7. The chirped grating spectrum shaping method according to claim 5, wherein: The step of calculating the exposure dose corresponding to each sub-gate region includes: For each layer of the sub-gate region, the exposure dose required for the sub-gate region is calculated according to a mapping relationship between the reflection coefficient of the sub-gate region and the exposure dose.

8. An electronic device, characterized in that: The electronic device comprises: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the computer program is configured to implement the steps of the chirped grating spectrum shaping method according to any one of claims 5 to 7.

9. A storage medium, characterized in that: The storage medium is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by a processor, the steps of the chirped grating spectrum shaping method according to any one of claims 5 to 7 are implemented.

10. A computer program product, characterized in that The computer program product includes a computer program, and when the computer program is executed by a processor, the steps of the chirped grating spectrum shaping method described in any one of 5 to 7 are implemented.

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