Control method for improving stability of output power of laser

Abstract

The invention relates to the technical field of lasers, and discloses a control method for improving the power stability of a laser. The control method for improving the power stability of the laser comprises the following steps: firstly, calibrating steady-state parameters of the laser, including but not limited to the output power of the laser and the environmental physical quantity of an inner cavity of the laser; secondly, discrete sampling is carried out on the output power of the laser and the environmental physical quantity of the inner cavity of the laser, N times of discrete sampling data are grouped and preprocessed according to the physical quantity, and N is a positive integer larger than 1; then, relative deviation is calculated by using the preprocessed data and laser steady-state parameters, feature vectors are constructed by using the relative deviation, and different weights are distributed to each item in the feature vectors to form weighted feature vectors; and finally calculating a characteristic value of the weighted characteristic vector, and adjusting an output laser power value according to the characteristic value. The influence of environmental factors on the laser power detection value is reduced, and the stability of the output power of the laser is improved.

Description

Technical Field

[0001] The present invention relates to the field of laser technology, and in particular to a control method for improving the stability of laser output power. Background Art

[0002] During laser operation, fluctuations in both the laser's components and the environment can lead to unstable output power. Existing solutions monitor output power using optical power sensors and provide feedback to adjust output power based on power fluctuations. However, optical power sensors themselves are also affected by environmental factors, resulting in inaccurate output data. For example, they can amplify or reduce the range of laser power fluctuations, thus affecting the determination of laser output power stability. Summary of the Invention

[0003] Based on the above, an object of the present invention is to provide a control method for improving the stability of laser output power, so as to reduce the influence of environmental factors on the optical power sensor, thereby improving the laser power stability.

[0004] To achieve the above object, the present invention adopts the following technical solutions:

[0005] A control method for improving the stability of laser output power includes the following steps:

[0006] S1. Calibrate the laser steady-state parameters, including but not limited to the laser output power and the environmental physical quantities of the laser cavity;

[0007] S2, discretely sampling the output power of the laser and the environmental physical quantities of the laser cavity;

[0008] S3. Grouping the data of N discrete samples according to physical quantities, where N is a positive integer greater than 1;

[0009] S4. Preprocess each set of data;

[0010] S5, using the pre-processed data and the laser steady-state parameters to calculate the relative deviation, and using the relative deviation to construct a feature vector (m1, m2, ..., m n );

[0011] S6, give the feature vector (m1, m2, ..., m n ) is assigned different weights a1, a2, ..., a n , forming a weighted feature vector (a1m1, a2m2, ..., a n m n );

[0012] S7, calculating the eigenvalue of the weighted eigenvector;

[0013] S8. Adjust the output laser power value according to the characteristic value.

[0014] As a preferred solution for a control method for improving the stability of laser output power, the environmental physical quantities of the laser cavity include but are not limited to temperature T, humidity H, and structural component offset S;

[0015] Discrete sampling of the environmental physical quantities of the laser cavity includes but is not limited to temperature T n 、Humidity H n and structural member offset S n .

[0016] As a preferred solution for a control method for improving the stability of laser output power, a method for preprocessing each set of data includes calculating the arithmetic square root of each set of physical quantity data;

[0017] y1 represents the output power P n The arithmetic square root of

[0018] y2 represents temperature T n The arithmetic square root of

[0019] y3 represents humidity H n The arithmetic square root of

[0020] y4 represents the structural member offset S n The arithmetic square root of .

[0021] As a preferred solution for a control method to improve the stability of laser output power, the method for constructing the characteristic vector is expressed by the following formula:

[0022]

[0023] Where y represents a physical quantity;

[0024] n is a natural number, representing the serial number of the physical quantity;

[0025] R represents the calibration value of the physical quantity y.

[0026] As a preferred solution for a control method to improve the stability of laser output power, the method includes the following subdivision steps:

[0027] S8-1, dividing the characteristic value into quantitative levels, including a compensation threshold and an alarm threshold;

[0028] S8-2, determining the quantization level of the characteristic value,

[0029] If the characteristic value is less than the compensation threshold, outputting the detected laser power value;

[0030] If the characteristic value reaches the compensation threshold but does not reach the alarm threshold, the laser power compensation amount is calculated according to the characteristic value, and the compensated laser power value is output;

[0031] If the characteristic value reaches the alarm threshold, an alarm signal is output.

[0032] The beneficial effects of the present invention are:

[0033] The present invention first calibrates the laser steady-state parameters, including but not limited to the laser output power and the environmental physical quantities of the laser cavity. The laser output power and the environmental physical quantities of the laser cavity are then discretely sampled, and the data from N discrete samples is grouped and preprocessed according to the physical quantities, where N is a positive integer greater than 1. The preprocessed data and the laser steady-state parameters are then used to calculate relative deviations. A eigenvector is then constructed using the relative deviations, and each item in the eigenvector is assigned a different weight to form a weighted eigenvector. Finally, the eigenvalues of the weighted eigenvector are calculated, and the output laser power value is adjusted based on the eigenvalues, thereby reducing the influence of environmental factors on the laser power detection value, thereby improving the stability of the laser output power. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in describing the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the contents of the embodiments of the present invention and these drawings without any creative work.

[0035] Figure 1 The present invention is a control method for improving the stability of laser output power;

[0036] Figure 2 This is a flow chart of a control method for improving the stability of laser output power provided by a specific embodiment of the present invention;

[0037] Figure 3 This is a detailed flow chart of a control method for improving the stability of laser output power provided by a specific embodiment of the present invention; DETAILED DESCRIPTION

[0038] To make the technical problems solved by the present invention, the technical solutions adopted, and the technical effects achieved more clearly, the technical solutions of the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making any creative efforts shall fall within the scope of protection of the present invention.

[0039] like Figure 1 As shown, this embodiment provides a control method for improving the stability of laser output power, including the following steps:

[0040] S1. Calibrate the laser steady-state parameters, including but not limited to the laser output power and the environmental physical quantities of the laser cavity;

[0041] S2, discretely sampling the output power of the laser and the environmental physical quantities of the laser cavity;

[0042] S3. Grouping the data of N discrete samples according to physical quantities, where N is a positive integer greater than 1;

[0043] S4. Preprocess each set of data;

[0044] S5, use the preprocessed data and the laser steady-state parameters to calculate the relative deviation, and use the relative deviation to construct the feature vector (m1, m2, ..., m n );

[0045] S6. Give the eigenvector (m1, m2, ..., m n ) is assigned different weights a1, a2, ..., a n , forming a weighted feature vector (a1m1, a2m2, ..., a n m n );

[0046] S7. Calculate the eigenvalue of the weighted eigenvector;

[0047] S8. Adjust the output laser power value according to the characteristic value.

[0048] The present invention reduces the influence of environmental factors on the laser power detection value, thereby improving the stability of the laser output power.

[0049] Specifically, in this embodiment, the laser steady-state parameters are calibrated. These parameters include the laser output power P, and the environmental physical quantities of the laser cavity, including temperature T, humidity H, and structural component offset S. More specifically, the laser steady-state parameters are calibrated during the experimental phase before the laser is fully integrated. A power meter external to the laser is used to measure the laser power, and the environmental physical quantities of the laser cavity, including temperature T, humidity H, and structural component offset S, are recorded. After calibration, this data is recorded in a memory and serves as a reference value for subsequent algorithms to adjust the laser power value.

[0050] After the laser is integrated, the output power of the laser and the environmental physical quantities of the laser cavity are discretely sampled in the use stage, including the output power P of the laser n , temperature T n 、Humidity Hn and structural member offset S n Specifically, the laser's built-in optical power sensor is used to collect the laser's output power P n , use the laser's built-in temperature sensor to collect the temperature T n , use the humidity sensor built into the laser to collect humidity H n ,The built-in displacement sensor of the laser is used to collect the displacement of key components in the optical path such as the lens and optical power sensor relative to their original positions, and the collected data is recorded in the memory.

[0051] The data from N discrete samples is grouped by physical quantity, where N is a positive integer greater than 1. Specifically, in this embodiment, N is 10, meaning each group of physical quantities contains 10 sample data. More specifically, after 10 samples, the data is grouped by the four physical quantities of output power, temperature, humidity, and structural component offset, resulting in four groups in total, each containing 10 sample data.

[0052] Each set of data was preprocessed by calculating the arithmetic square root to eliminate sampling errors.

[0053] y1 represents the output power P n The arithmetic square root of

[0054] y2 represents temperature T n The arithmetic square root of

[0055] y3 represents humidity H n The arithmetic square root of

[0056] y4 represents the structural member offset S n The arithmetic square root of .

[0057] The relative deviation is calculated using the preprocessed data and the laser steady-state parameters, and the feature vector (m1, m2, ..., m n ). Specifically, in this embodiment, the method of constructing the feature vector is expressed by the following formula:

[0058]

[0059] Where y represents a physical quantity;

[0060] n is a natural number, representing the serial number of the physical quantity;

[0061] R represents the calibration value of the physical quantity y.

[0062] Since in this embodiment, only the influence of temperature, humidity and structural component offset on the output power is considered, the above eigenvector is a 4-dimensional eigenvector, namely

[0063]

[0064] Where y1 represents the output power P n The arithmetic square root of y2 represents the temperature T n The arithmetic square root of

[0065] y3 represents humidity H n The arithmetic square root of y4 represents the structural member offset S n The arithmetic square root of .

[0066] n is a natural number, representing the serial number of the physical quantity;

[0067] R1 represents the output power P n Calibration value; R2 represents temperature T n The calibration value; R3 represents the humidity H n Calibration value; R4 represents the structural component offset S n The calibration value of .

[0068] It should be further noted that the present invention is not limited to the specific embodiments described herein, and that those skilled in the art can make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention.

[0069] Given the eigenvectors (m1, m2, ..., m n ) is assigned different weights a1, a2, ..., a n , forming a weighted feature vector (a1m1, a2m2, ..., a n m n ). Specifically, in the embodiment, a1 represents the output power P n The weight of a2 represents the temperature T n The weight of a3 represents the humidity H n The weight of a4 represents the offset of the structural member S n The weights of different physical quantities need to be determined by combining experimental data and theoretical analysis. For example, in this embodiment, the weights of the above four physical quantities are 6:1:1:2.

[0070] Calculate the eigenvalue of the weighted eigenvector. This eigenvalue represents the output power P n The deviation value affected by the other three variables. The formula for calculating the eigenvalue is as follows

[0071]

[0072] Here, k represents the eigenvalue.

[0073] m1, m2, m3, and m4 represent the corresponding items of the eigenvectors (m1, m2, m3, and m4), respectively.

[0074] The characteristic value represents the output power P n There are many ways to adjust the output laser power value according to the characteristic value of the deviation value affected by the other three variables, which are exemplified here. Figure 2 shown.

[0075] Adjusting the output laser power value according to the characteristic value includes the following subdivision steps:

[0076] S8-1, dividing the characteristic value into quantitative levels, including a compensation threshold and an alarm threshold;

[0077] S8-2, determining the quantization level of the characteristic value,

[0078] If the characteristic value is less than the compensation threshold, outputting the detected laser power value;

[0079] If the characteristic value reaches the compensation threshold but does not reach the alarm threshold, the laser power compensation amount is calculated according to the characteristic value, and the compensated laser power value is output;

[0080] If the characteristic value reaches the alarm threshold, an alarm signal is output.

[0081] Note that the above are only preferred embodiments of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments, and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments and may include many other equivalent embodiments without departing from the concept of the present invention. The scope of the present invention is determined by the scope of the appended claims.

[0082] In the description of the present invention, it should be noted that the terms "center," "up," "down," "left," "right," "vertical," "horizontal," "inside," and "outside" and the like, indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended only to facilitate the description of the present invention and simplify the description. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The terms "first position" and "second position" refer to two different positions.

[0083] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

Claims

1. A control method for improving laser power stability, characterized in that: The following steps are involved: S1. Calibrate the laser steady-state parameters, including but not limited to the laser output power and the environmental physical quantities of the laser cavity; S2, discretely sampling the output power of the laser and the environmental physical quantities of the laser cavity; S3. Grouping the data of N discrete samples according to physical quantities, where N is a positive integer greater than 1; S4. Preprocess each set of data; S5, using the pre-processed data and the laser steady-state parameters to calculate the relative deviation, and using the relative deviation to construct a feature vector (m1, m2, ..., m n ); S6, give the feature vector (m1, m2, ..., m n ) are assigned different weights a1, a2, ..., a n , forming a weighted feature vector (a1m1, a2m2, ..., a n m n ); S7, calculating the eigenvalue of the weighted eigenvector; S8. Adjust the output laser power value according to the characteristic value.

2. The control method for improving laser power stability according to claim 1, characterized in that: The environmental physical quantities of the laser cavity include but are not limited to temperature T, humidity H, and structural component offset S; Discrete sampling of the environmental physical quantities of the laser cavity includes but is not limited to temperature T n 、Humidity H n and structural member offset S n .

3. The control method for improving laser power stability according to claim 1, characterized in that: The method of preprocessing each set of data includes calculating the arithmetic square root of each set of physical quantity data; y1 represents the output power P n The arithmetic square root of y2 represents temperature T n The arithmetic square root of y3 represents humidity H n The arithmetic square root of y4 represents the structural member offset S n The arithmetic square root of .

4. The control method for improving laser power stability according to claim 1, characterized in that: The method of constructing the feature vector is expressed by the following formula:

5. Where y represents a physical quantity; n is a natural number, representing the serial number of the physical quantity; R represents the calibration value of the physical quantity y.

6. The control method for improving laser power stability according to claim 1, characterized in that: The following subdivision steps are included: S8-1, dividing the characteristic value into quantitative levels, including a compensation threshold and an alarm threshold; S8-2, determining the quantization level of the characteristic value, If the characteristic value is less than the compensation threshold, outputting the detected laser power value; If the characteristic value reaches the compensation threshold but does not reach the alarm threshold, the laser power compensation amount is calculated according to the characteristic value, and the compensated laser power value is output; If the characteristic value reaches the alarm threshold, an alarm signal is output.

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