A method for power correction of a fiber laser

Abstract

The application relates to a power correction method of a fiber laser, which comprises the following steps: setting laser output power, acquiring a power simulation curve; running the laser, acquiring N measurement values of the laser output power, generating a power sampling curve, wherein N>=10; acquiring a power difference value of the power simulation curve and the power sampling curve; acquiring a compensation gain of the output power according to the power difference value; selecting a compensation mode according to the compensation gain; correcting the working condition of the fiber laser according to the selected compensation mode, so as to correct the output power of the fiber laser and reduce the error between the set power and the actual output power. Before long-term operation of the fiber laser, the deviation of the output power can be accurately identified, and the working condition of the laser is adjusted according to the compensation gain calculated according to the power difference value. The method is periodically or on-demand executed, the power of the corrected fiber laser is stable, the output power fluctuation caused by real-time factors such as the back light and the pump light in the fiber is avoided, and the method is more accurate, stable and reliable in the correction of the power of the fiber laser.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of fiber lasers, in particular to a power correction method of a fiber laser. BACKGROUND

[0002] In the fiber laser, due to the nonlinear characteristics of the pump source and the inconsistency of the fiber conversion efficiency, only by linear current control of the pump source, the accurate linear power output cannot be achieved, resulting in a large deviation between the set power and the actual output optical power. Moreover, due to the difference of the fiber and the pump source, the produced machines have great difference, the output power has great difference and the error is not fixed when the same power is set. For example, when the laser output power is set to 1000W, the actual output power of some lasers may be only 900W or even lower. At present, the power correction technology of the fiber laser on the market mostly depends on real-time power feedback. However, this method has encountered many challenges in practical application. Due to the complex optical environment inside the fiber laser and the application terminal, such as material reflection, darkening caused by fiber aging, stray light, fiber cladding light, temperature change and other factors, the detection accuracy and precision of the photosensitive diode sensor or the thermal sensor for real-time feedback are seriously affected. These interferences make it difficult for the sensor to accurately capture the effective optical power data in the fiber, and the reflected light and pump light in the fiber further interfere with the accuracy of the collected data. Therefore, the method based on real-time power feedback often leads to unstable optical power output and fluctuation of the feedback reference in practical application, thereby affecting the performance of the stable output of the fiber laser.

[0003] In order to solve this problem, it is urgent to develop a stable and effective optical power compensation method to improve the output power accuracy and stability of the fiber laser, ensure the consistency of the set power and the actual output power, and make the terminal customer application more convenient and stable. SUMMARY

[0004] Therefore, in view of the above problems, the present application provides a power correction method of a fiber laser, which greatly improves the stability of the output power of the laser and ensures the consistency of the set power and the actual output power.

[0005] To achieve the above purpose, the present application provides a power correction method of a fiber laser, comprising the following steps: setting the output power of the laser, obtaining a power simulation curve; running the laser, obtaining N measurement values of the output power of the laser, generating a power sampling curve, wherein N≥10; obtaining the power difference value between the power simulation curve and the power sampling curve; obtaining the compensation gain of the output power according to the power difference value; selecting a compensation mode according to the compensation gain; correcting the working condition of the fiber laser according to the selected compensation mode to correct the output power of the fiber laser.

[0006] In one embodiment, the compensation method includes at least one of correcting the current of the pump source, correcting the fiber parameter, and adjusting the internal temperature of the fiber laser.

[0007] In one embodiment, the step of obtaining the compensation gain of the output power according to the power difference includes using one of a polynomial, an exponential function, a logarithmic function, and a power function to obtain the compensation gain.

[0008] In one embodiment, the step of obtaining the compensation gain of the output power according to the power difference is followed by a step of performing statistical analysis according to the compensation gain of the output power, and triggering a hierarchical warning signal when the compensation gain exceeds a threshold value.

[0009] In one embodiment, the hierarchical warning signal includes a first-level warning signal, a second-level warning signal, a third-level warning signal, a fourth-level warning signal, and a fifth-level warning signal, wherein the first-level warning signal is used to adjust the internal temperature of the fiber laser, the second-level warning signal is used to correct the fiber parameter, the third-level warning signal is used to correct the current of the pump source, the fourth-level warning signal is used to correct at least two of the current of the pump source, the fiber parameter, and the internal temperature of the fiber laser, and the fifth-level warning signal is used to correct the current of the pump source, the fiber parameter, and the internal temperature of the fiber laser.

[0010] In one embodiment, the step of correcting the fiber parameter includes changing any one of the refractive index, the length, or the shape of the fiber.

[0011] In one embodiment, the method further includes a step of obtaining an ambient temperature and obtaining a first correction gain of the output power of the laser according to the ambient temperature.

[0012] In one embodiment, the method further includes a step of obtaining an ambient humidity and obtaining a second correction gain of the output power of the laser according to the ambient humidity.

[0013] In one embodiment, the method further includes a step of obtaining an ambient air pressure and obtaining a third correction gain of the output power of the laser according to the ambient air pressure.

[0014] In one embodiment, the method further includes a step of obtaining an ambient temperature, humidity, and air pressure and obtaining a fourth correction gain of the output power of the laser according to the ambient temperature, humidity, and air pressure.

[0015] Compared with the prior art, the present application has the following advantages:

[0016] This invention provides a power correction method for fiber lasers. Before long-term operation of the fiber laser, multiple measured values ​​of the laser's output power are acquired and a power sampling curve is generated. This curve is then compared with the set power to accurately identify the deviation in output power. Based on the compensation gain calculated from the power difference, the operating conditions of the laser are adjusted accordingly, significantly improving the stability of the laser's output power. Regularly or as needed, this method can ensure that the laser maintains optimal performance during long-term use and extend its service life. Attached Figure Description

[0017] Figure 1 This is a schematic diagram illustrating the workflow of a power correction method for a fiber laser according to the present invention.

[0018] Figure 2 This is a schematic diagram comparing the output power of a fiber laser before and after using the power correction method of the present invention.

[0019] Figure 3 This is a schematic diagram showing the output power effect after applying the power correction method for a fiber laser according to the present invention. Detailed Implementation

[0020] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0021] like Figure 1 As shown, this embodiment provides a power correction method for a fiber laser, including the following steps: setting the laser output power and obtaining a power simulation curve; running the laser and using a power meter to obtain N measured values ​​of the laser output power, generating a power sampling curve, where N≥10, and the number of power measurements can be 15, 20, 25, 30, 35, 40, 50, 80, 100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, or even more; obtaining the power difference P between the power simulation curve and the power sampling curve. df The compensation gain P of the output power is obtained based on the power difference. cp According to the compensation gain P cpThe compensation mode is selected; and the working condition of the fiber laser is corrected according to the selected compensation mode, so as to correct the output power of the fiber laser. The power correction method of the fiber laser provided by the embodiment can accurately identify the deviation of the output power by obtaining a plurality of measured values of the output power of the fiber laser and generating a power sampling curve, and then comparing the power sampling curve with a power simulation curve, before long-term operation of the fiber laser, such as before leaving the factory, before use or during long-term operation maintenance. The working condition of the laser is adjusted according to the compensation gain calculated based on the power difference, which significantly improves the stability of the output power of the laser, improves the consistency of the set power and the actual output power, and ensures that the laser maintains the best performance during long-term use and prolongs the service life. The power correction method of the fiber laser provided by the embodiment does not belong to real-time power monitoring and feedback. The accuracy of the collected data is effectively shielded from the negative effects of the back light and pump light in the fiber during the correction process. After correction, the running fiber laser power is stable, and the output power will not fluctuate due to the influence of real-time factors such as back light and pump light in the fiber. The power correction method overcomes the defects of low accuracy, large environmental impact and power fluctuation of the real-time power feedback method. The output power of the fiber laser is more accurate, stable and reliable, and ensures that the output power is consistent with the set power.

[0022] In one embodiment, the compensation mode includes at least one of correcting the current of the pump source, correcting the fiber parameter, and adjusting the internal temperature of the fiber laser.

[0023] In one embodiment, the step of obtaining the compensation gain of the output power according to the power difference includes obtaining the compensation gain by using a polynomial. For example, the compensation gain is obtained by using the formula y=k n x n +k n-1 x n-1 +k n-2 x n-2 +k n-3 x n-3 ......+ k1x+ k0, where k0 to k nFor preset parameters, x is any one of current control input, refractive index of the optical fiber, length value of the optical fiber or internal temperature value of the fiber laser, and y is target output power value. Exemplarily, one of exponential function, logarithmic function and power function can be used to obtain the compensation gain. Table 1 is a comparison table of measured values before and after power correction of the fiber laser using the power correction method of the fiber laser provided in the embodiment. As can be seen from Table 1, the error between the set power and the actual output power measurement value before correction reaches 63.69% at most. The power measurement value after processing by the power correction method of the fiber laser provided in the embodiment is basically equivalent to the set power value, and the maximum error is 0.59%, which realizes accurate optical power correction. The method can improve the stability and accuracy of the output power of the fiber laser, and is suitable for various application scenarios. Figure 2 The output power measurement value comparison before power correction of the fiber laser is shown. Figure 2 As can be seen from the table, there is a large error between the output power before correction and the set power. Figure 3 After the power correction method of the fiber laser provided in the embodiment, the output power measurement value and the set power are basically coincided, and the output power of the fiber laser is obviously improved, greatly optimizing the performance of the fiber laser.

[0024] Table 1 Comparison table of measured values before and after power correction of the fiber laser

[0025]

[0026] (Note: error = (set power-power measurement value) ÷ set power × 100%)

[0027] In one of the embodiments, according to the power difference P df The compensation gain P cp After the step, it further includes: according to the output power compensation gain P cp Statistical analysis is performed, and when the compensation gain P cp exceeds the threshold, a hierarchical warning signal is triggered. The hierarchical warning signal includes: a first-level warning signal, according to which the internal temperature of the fiber laser is adjusted; a second-level warning signal, according to which the fiber parameters are corrected; a third-level warning signal, according to which the current of the pump source is corrected; a fourth-level warning signal, according to which at least two of the current of the pump source, the correction of the fiber parameters and the adjustment of the internal temperature of the fiber laser are performed; and a fifth-level warning signal, according to which the current of the pump source, the correction of the fiber parameters and the adjustment of the internal temperature of the fiber laser are corrected. Specifically, the power compensation gain P cp is compared with a preset data mapping table, when A1≤P cp <A2, a first-level warning signal is triggered; when A2≤P cpWhen A3, trigger the second level early warning signal; when A3≤P cp When A4, trigger the third level early warning signal; when A4≤P cp When A5, trigger the fourth level early warning signal; when A5≤P cp When A6, trigger the fifth level early warning signal; when A6≤P cp When A6, trigger the fifth level early warning signal; when A6≤P When A6, trigger the fifth level early warning signal; when A6≤P The embodiment adopts the hierarchical early warning and alarm method, provides clear and targeted guidance for the output power optimization of the fiber laser, and the user can quickly identify and take appropriate compensation mode to correct the working condition of the fiber laser according to the early warning signals of different levels, so that the accuracy and efficiency of power compensation are significantly improved.

[0028] In one of the embodiments, the correction of the fiber parameters includes any one of changing the refractive index, length or shape of the fiber.

[0029] In one of the embodiments, the power correction method of the fiber laser further includes the steps of: obtaining the ambient temperature, obtaining the first correction gain g1 of the laser output power according to the ambient temperature, at this time, y1= g 1+ y.

[0030] In one of the embodiments, the power correction method of the fiber laser further includes the steps of: obtaining the ambient humidity, obtaining the second correction gain g2 of the laser output power according to the ambient humidity, at this time, y2= g 2+ y.

[0031] In one of the embodiments, the power correction method of the fiber laser further includes the steps of: obtaining the ambient pressure, obtaining the third correction gain g3 of the laser output power according to the ambient pressure, at this time, y3= g 3+ y.

[0032] In one of the embodiments, the power correction method of the fiber laser further includes the steps of: obtaining the ambient temperature, humidity and pressure, obtaining the fourth correction gain of the laser output power according to the ambient temperature, humidity and pressure, at this time, y4= g 1+ g 2+ g 3+ y.

[0033] The power correction method of the fiber laser provided by the application can improve the stability of the output power of the fiber laser, enhance the long-term operation reliability, provide flexible and various compensation modes, introduce the hierarchical early warning and alarm mechanism, and promote the optimization and improvement of the performance of the fiber laser.

[0034] It is to be understood that the application is not limited to the details of the above-exemplified embodiments and that the present application can be carried out in other concrete ways without departing from the spirit or essential characteristics of the application. Consequently, all changes and modifications that can suggest themselves to one skilled in the art have to be seen as being within the scope of the present application as defined by the following claims. The embodiments are to be considered in all respects as illustrative only and not restrictive of the application described and claimed herein. The application is therefore not to be limited to the specific embodiments described herein, but only by the scope of the appended patent claims and their equivalents.

[0035] The above examples are illustrative of the principles and embodiments of the application. They are not meant to limit the scope of the application, which is defined by the claims. The application is not limited to the specific details described herein.

Claims

1. A method of power correction for a fiber laser, the method comprising: The method comprises the following steps: ​ setting a laser output power, and obtaining a power simulation curve; running the laser, obtaining N measurement values of the laser output power, and generating a power sampling curve, wherein N≥10; obtaining a power difference value between the power simulation curve and the power sampling curve; obtaining a compensation gain of the output power according to the power difference value; selecting a compensation mode according to the compensation gain; correcting the working condition of the fiber laser according to the selected compensation mode, so as to correct the output power of the fiber laser, after the step of obtaining the compensation gain of the output power according to the power difference value, further comprising: performing statistical analysis according to the output power compensation gain, triggering a hierarchical early warning signal when the compensation gain exceeds a threshold value, wherein the hierarchical early warning signal comprises: a first-level early warning signal, adjusting the internal temperature of the fiber laser according to the first-level early warning signal; a second-level early warning signal, correcting the fiber parameters according to the second-level early warning signal; a third-level early warning signal, correcting the current of the pump source according to the third-level early warning signal; a fourth-level early warning signal, correcting at least two of the current of the pump source, the fiber parameters, and the internal temperature of the fiber laser according to the fourth-level early warning signal; and a fifth-level early warning signal, correcting the current of the pump source, the fiber parameters, and the internal temperature of the fiber laser according to the fifth-level early warning signal. The power correction method of the fiber laser is executed before long-term operation of the fiber laser, including before leaving the factory, before use, or during maintenance, so as to avoid real-time feedback interference.

2. The method of claim 1, wherein: The compensation mode comprises at least one of correcting the current of the pump source, correcting the fiber parameters, and adjusting the internal temperature of the fiber laser.

3. The method of claim 1, wherein: The step of obtaining the compensation gain of the output power according to the power difference value comprises using one of a polynomial, an exponential function, a logarithmic function, and a power function to obtain the compensation gain.

4. The method of claim 1 or 2, wherein: The correction of the fiber parameters comprises changing any one of the refractive index, the length, or the shape of the fiber.

5. The method of claim 1, wherein: The method further comprises the steps of: obtaining an ambient temperature, and obtaining a first correction gain of the laser output power according to the ambient temperature.

6. The method of claim 1, wherein: The method further comprises the steps of: obtaining an ambient humidity, and obtaining a second correction gain of the laser output power according to the ambient humidity.

7. The method of claim 1, wherein: The method further comprises the steps of: obtaining an ambient air pressure, and obtaining a third correction gain of the laser output power according to the ambient air pressure.

8. The method of claim 1, wherein: The method further comprises the steps of: obtaining the ambient temperature, humidity, and air pressure, and obtaining a fourth correction gain of the laser output power according to the ambient temperature, humidity, and air pressure.

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