Laser temperature control method and related equipment

Abstract

The present invention discloses a laser temperature control method and related equipment. The method includes: obtaining a temperature-current fitting function of a laser to be controlled based on thermal principles, wherein the temperature-current fitting function is a fitting function of the laser temperature and the TEC current; and controlling the regulating current of the laser to be controlled based on the temperature-current fitting function and a PID control algorithm to control the temperature of the laser to be controlled within a preset temperature range. The method provided in an embodiment of the present application obtains a temperature-current fitting function of the laser to be controlled based on thermal principles, and controls the temperature of the laser by combining a PID algorithm and the temperature-current fitting function. On the basis of a conventional PID adjustment algorithm, a correction and adjustment function of the TEC current by using the temperature-current fitting function is added when the laser temperature reaches a stable state, thereby improving its temperature control accuracy and solving the problem of insufficient temperature control accuracy of a stabilized frequency laser.

Description

Technical Field

[0001] This specification relates to the field of frequency-stabilized lasers, and more specifically, to a laser temperature control method and related equipment. Background Art

[0002] In fields such as laser precision metrology, laser communications, high-resolution spectroscopy, and laser cold atom experiments, not only are lasers required to be single-piece, but also to have a certain degree of frequency stability. Fluctuations in ambient temperature or temperature changes caused by the heat generated by the laser tube during operation can cause the laser cavity material to expand and contract with temperature changes, resulting in frequency drift. To achieve better frequency stability and ensure the operating performance of the frequency-stabilized laser, a TEC (thermoelectric cooler) is often introduced into the optical module to drive the TEC to improve the temperature control accuracy of the laser.

[0003] Among existing laser temperature control methods, the PID control algorithm is the most commonly used, utilizing a closed-loop control algorithm to achieve effective temperature regulation. Both practical operational experience and theoretical analysis have demonstrated that this control principle can achieve relatively satisfactory results in controlling many industrial processes. However, strict control and trade-offs between control accuracy and speed are required. To achieve faster regulation speed, a larger proportional coefficient Kp can be set. However, as the temperature stabilizes, a larger Kp will amplify calculation errors, resulting in a loss of temperature accuracy. While PID control avoids the use of complex temperature models or temperature relationship functions, since PID controllers are linear controllers, which in reality are often nonlinear, using linear approximations to represent nonlinearity can reduce temperature control accuracy. Summary of the Invention

[0004] The Summary of the Invention introduces a series of simplified concepts that will be further described in the Detailed Description of the Invention. The Summary of the Invention is not intended to limit the key features and essential features of the claimed technical solution, nor is it intended to determine the scope of protection of the claimed technical solution.

[0005] In a first aspect, the present invention provides a laser temperature control method, the method comprising:

[0006] Obtaining a temperature-current fitting function of the laser to be controlled based on thermal principles, wherein the temperature-current fitting function is a fitting function of the laser temperature and the TEC current;

[0007] The regulating current of the laser to be controlled is controlled according to the temperature-current fitting function and the PID control algorithm to control the temperature of the laser to be controlled within a preset temperature range.

[0008] Optionally, controlling the regulating current of the laser to be controlled according to the temperature-current fitting function and the PID control algorithm to control the temperature of the laser to be controlled within a preset temperature range includes:

[0009] When the fitting correlation coefficient corresponding to the temperature-current fitting function is less than or equal to a preset threshold, a PID control algorithm is used to control the regulating current of the laser to be controlled to control the temperature of the laser to be controlled within a preset temperature range.

[0010] Optionally, controlling the regulating current of the laser to be controlled according to the temperature-current fitting function and the PID control algorithm to control the temperature of the laser to be controlled within a preset temperature range includes:

[0011] When the fitting correlation coefficient corresponding to the temperature-current fitting function is greater than a preset threshold, the real-time temperature of the laser to be controlled is obtained through the thermistor;

[0012] Determine the current preload current based on the above real-time temperature and PID control algorithm;

[0013] Determine the predicted operating temperature using the temperature-current fitting function and the current preload current;

[0014] In a case where the predicted operating temperature is within the preset temperature range, the temperature of the laser to be controlled is controlled according to the current preload current.

[0015] Optionally, the above method further includes:

[0016] In the case where the predicted operating temperature exceeds the preset temperature range, reversely calculating the corrected loading current based on the temperature-current fitting function;

[0017] The temperature of the laser to be controlled is controlled based on the corrected loading current.

[0018] Optionally, the above-mentioned obtaining of the temperature and current fitting function of the laser to be controlled based on thermal principles includes:

[0019] Based on thermal principles, the overall heat dissipation model of the laser system is constructed in the form of functional equations;

[0020] Perform curve fitting on the above function equation according to the temperature information and current information of the laser to be controlled;

[0021] In a case where the corresponding fitting correlation coefficient of the functional equation is greater than or equal to a preset threshold, the functional equation is determined as the temperature-current fitting function.

[0022] Optionally, the above functional equation includes a linear functional equation;

[0023] The above method further includes:

[0024] Obtaining temperature fluctuation information of the laser to be controlled within a current preset time period;

[0025] The curve fitting of the above function equation according to the temperature information and current information of the laser to be controlled includes:

[0026] In the case that the temperature floating information meets the preset floating error requirement, curve fitting is performed on the function equation according to the temperature information and current information of the laser to be controlled.

[0027] Optionally, the above method further includes:

[0028] The temperature information and the current information within a target number of cycles are obtained, wherein the target number is greater than the number of unknown coefficients corresponding to the function equation.

[0029] Optionally, the above method further includes:

[0030] When the preset temperature range changes, a PID control algorithm is used to control the regulating current of the laser to be controlled so as to control the temperature of the laser to be controlled;

[0031] again performing curve fitting on the function equation according to the temperature information and current information of the laser to be controlled;

[0032] When the corresponding fitting correlation coefficient of the functional equation is again greater than or equal to the preset threshold, determining the functional equation as a second temperature-current fitting function;

[0033] The temperature of the laser to be controlled is controlled according to the second temperature-current fitting function.

[0034] In a second aspect, the present invention further provides a laser temperature control device, comprising:

[0035] An acquisition unit is used to acquire a temperature-current fitting function of the laser to be controlled based on thermal principles, wherein the temperature-current fitting function is a fitting function of the laser temperature and the TEC current;

[0036] The control unit is used to control the regulating current of the laser to be controlled according to the temperature-current fitting function and the PID control algorithm so as to control the temperature of the laser to be controlled within a preset temperature range.

[0037] In a third aspect, an electronic device comprises: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor is configured to implement the steps of the laser temperature control method according to any one of the first aspects when executing the computer program stored in the memory.

[0038] In summary, the laser temperature control method of the embodiment of the present application includes: obtaining a temperature-current fitting function of the laser to be controlled based on thermal principles; controlling the adjustment current of the laser to be controlled based on the temperature-current fitting function and the PID control algorithm to control the temperature of the laser to be controlled within a preset temperature range. The method provided in the embodiment of the present application obtains the temperature-current fitting function of the laser to be controlled based on thermal principles, and controls the temperature of the laser by combining the PID algorithm and the temperature-current fitting function. On the basis of the conventional PID adjustment algorithm, it adds a correction and adjustment function of the TEC current through the temperature-current fitting function when the laser temperature reaches a stable state, thereby improving its temperature control accuracy and solving the problem of insufficient temperature control accuracy of the stabilized frequency laser.

[0039] The laser temperature control method proposed in this application, and other advantages, objectives and features of the present invention will be partially reflected in the following description, and will also be partially understood by those skilled in the art through research and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiment below. The accompanying drawings are for illustration purposes only and are not to be considered as limiting the present description. The same reference symbols are used throughout the drawings to represent the same components. In the drawings:

[0041] Figure 1 A schematic flow chart of a laser temperature control method provided in an embodiment of the present application;

[0042] Figure 2 A schematic diagram of a sampling point determination principle provided in an embodiment of the present application;

[0043] Figure 3 A schematic flow chart of another laser temperature control method provided in an embodiment of the present application;

[0044] Figure 4 A flow chart of a method for determining a relationship function provided in an embodiment of the present application;

[0045] Figure 5 A schematic diagram of the structure of a laser temperature control device provided in an embodiment of the present application;

[0046] Figure 6A schematic diagram of the structure of a laser temperature control electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0047] The terms "first", "second", "third", "fourth", etc. (if any) in the specification and claims of this application and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments described herein can be implemented in a sequence other than that illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or that are inherent to these processes, methods, products or devices. The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the embodiments described are only part of the embodiments of the present application, not all of the embodiments.

[0048] In the fields of laser precision measurement, laser communication, high-resolution spectroscopy, laser cold atom experiments, etc., the laser is not only required to be single-frequency, but also to have a certain frequency stability. Usually, the frequency stability (the ratio of the frequency drift of the laser during a continuous working time to the oscillation frequency, S = Δν / ν) and reproducibility (the relative change of the frequency when the laser is used in different places, times, and environments, R = δν / ν) are used to express the degree of laser frequency stability. In practical applications, both stability and reproducibility are required to be within 10 -8 above.

[0049] Fluctuations in ambient temperature or temperature changes caused by heat generation during operation of the laser tube will cause the laser cavity material to expand and contract with temperature changes, resulting in frequency drift, i.e., αΔT=ΔL / L=Δν / ν. ΔT is the temperature change, and α is the linear expansion coefficient of the laser cavity spacer material. Taking the commonly used materials as an example, hard glass α=10 -5 / ℃, quartz glass α=6*10 -7 / ℃, Invar α=9*10 -7 / ℃. To obtain better than 10 -8 In order to ensure the frequency stability and working performance of the frequency-stabilized laser, a semiconductor cooler (TEC) is introduced into the optical module to improve the temperature control accuracy of the laser by driving the TEC.

[0050] Among existing laser temperature control methods, the PID control algorithm is the most commonly used, utilizing a closed-loop control algorithm to achieve effective temperature regulation. Both practical operational experience and theoretical analysis have demonstrated that this control principle can achieve relatively satisfactory results in controlling many industrial processes. However, it requires strict control and trade-offs between control accuracy and speed. For example, if the set temperature is 25°C and the actual temperature is 30°C, the temperature difference is 5°C. To achieve faster regulation, a larger proportional coefficient, Kp, can be used. However, as the temperature stabilizes, if the actual temperature is 25.01°C and the temperature difference is only 0.01°C, a larger Kp will amplify calculation errors, resulting in a loss of temperature accuracy. In short, while PID control avoids the use of complex temperature models or temperature relationship functions, since PID controllers are linear controllers, which in reality are often nonlinear, using linear approximations to represent nonlinearity can reduce temperature control accuracy.

[0051] To address the limitations of the PID algorithm in nonlinear systems, various improvements have been developed in recent years, including fuzzy adaptive PID control, neural network-based PID control, and intelligent PID learning control. However, these methods require extensive computation and self-learning, placing higher performance demands on the control device (FPGA or ARM). Furthermore, the temperature model must be continuously modified for different lasers or different operating environments, increasing the complexity of the temperature control process.

[0052] To provide a flexible and precise method for controlling laser temperature, see Figure 1 , is a flow chart of a laser temperature control method provided in an embodiment of the present application, which may specifically include:

[0053] S110, obtaining a temperature and current fitting function of the laser to be controlled based on thermal principles, wherein the temperature and current fitting function is a fitting function of the laser temperature and the TEC current;

[0054] Exemplarily, a temperature-current fitting function of the laser to be controlled is obtained based on thermal principles, where the temperature is the temperature of the laser system and the current is the TEC current. A fitting relationship function F(T, ITEC) between the laser operating temperature in a stable state and the TEC current is preset in the form of unknown coefficients, and an error range of the relationship function fitting correlation coefficient R2 is preset; the laser operating temperature is set and a temperature accuracy range is preset; the TEC loading current information is adjusted using a PID algorithm to control the laser temperature to reach the set operating temperature, and the real-time temperature of the laser and the current information of the TEC are continuously recorded during the PID adjustment process; based on the real-time temperature and TEC current information of the laser, the unknown function coefficients in the relationship function F(T, ITEC) are fitted and calculated, and the fitting function coefficients and the fitting correlation coefficient R are updated in real time during the temperature adjustment process.2 , if R 2 If the preset correlation coefficient error requirement can be met, the TEC current can be further corrected and adjusted on the basis of the PID algorithm to jointly control the temperature of the laser.

[0055] S120 , controlling the regulating current of the laser to be controlled according to the temperature-current fitting function and the PID control algorithm to control the temperature of the laser to be controlled within a preset temperature range.

[0056] For example, after constructing the temperature-current fitting function, the TEC current correction adjustment function is turned on, and the current real-time temperature T of the laser is obtained through the thermistor. n , obtain the TEC current preload current I through the PID algorithm TECn , through the temperature current fitting function F(T,I TEC ) is used to calculate the predicted working temperature T n+1 ; Determine the calculated predicted operating temperature T n+1 Whether the preset temperature accuracy range is met. If the predicted working temperature T n+1 If the preset temperature accuracy range is met, the current preload current I TECn Provided to TEC. If the predicted operating temperature T n+1 If the preset temperature accuracy range is not met, it is modified to the set working temperature value, and then the temperature current preset relationship F(T,I TEC ) Reverse calculation output TEC correction loading current I' TECn , and the correction loading current I' TECn Provided to TEC to control the temperature of the laser within the preset temperature range. In all links of laser temperature regulation, the temperature current fitting function F(T,I TEC ) According to the real-time temperature and TEC current, the fitting function coefficient and fitting correlation coefficient are updated in real time. If and only if the fitting correlation coefficient R 2 The correction function of the fitting function is enabled only when the preset correlation coefficient error range is met; otherwise, the temperature control and adjustment are performed only by relying on the PID algorithm.

[0057] It should be noted that before temperature control is implemented, the laser's operating temperature preset range and temperature accuracy range must be set. This is typically determined by comparing the desired laser's stable output wavelength and the desired laser operating current to the corresponding laser wavelength versus temperature and current characteristic curve. Laser characteristics are highly sensitive to temperature. As junction temperature rises, the threshold current increases at a rate of 1% to 2% per °C, leading to increased noise and wavelength shifts. Therefore, to ensure stable laser operation, temperature control must be performed to prevent the output optical power at a given bias current from varying with ambient temperature. Practical devices are equipped with temperature control semiconductor coolers and thermistors. The preset temperature accuracy range is the fluctuation error within the actual laser temperature when the laser temperature is stabilized at the set value. For example, if the set temperature is 30°C and the preset accuracy range is ±0.01°C, then in this embodiment, the temperature control accuracy requirement is met when the laser's real-time temperature is within the range of 29.99 to 30.01°C. Those skilled in the art will appreciate that, in other embodiments, a preset temperature accuracy range may need to be set based on actual laser characteristics and temperature control requirements.

[0058] In summary, the method provided in the embodiment of the present application obtains the temperature-current fitting function of the laser to be controlled through thermal principles, and controls the temperature of the laser by combining the PID algorithm and the temperature-current fitting function. On the basis of the conventional PID adjustment algorithm, a correction and adjustment function of the TEC current through the temperature-current fitting function is added when the laser temperature reaches a stable state, thereby improving its temperature control accuracy and solving the problem of insufficient temperature control accuracy of the stabilized frequency laser.

[0059] In some examples, controlling the regulating current of the laser to be controlled according to the temperature-current fitting function and the PID control algorithm to control the temperature of the laser to be controlled within a preset temperature range includes:

[0060] When the fitting correlation coefficient corresponding to the temperature-current fitting function is less than a preset threshold, a PID control algorithm is used to control the regulating current of the laser to be controlled to control the temperature of the laser to be controlled within a preset temperature range.

[0061] For example, the present application presets the fitting relationship function F(T,I) between the laser operating temperature in a steady state and the TEC current in the form of unknown coefficients. TEC ) (i.e., temperature current fitting function), and preset the relationship function fitting correlation coefficient R 2 Error range of fitting relationship function F(T,I TEC ) The specific function form corresponding to is:

[0062] ΔT n =ΔTn―1 +f(I TECn , I TECn―1 )

[0063] Fitting correlation coefficient R 2 The error range is the degree of fit between the real-time detection data and the fitting relationship function. Correlation coefficient R 2 The closer its value is to 1, the higher the degree of agreement between the test data and the fitting function. The correlation coefficient error range (preset threshold) set in this embodiment is R 2 >0.99, that is, when the correlation coefficient of the fitting function is greater than 0.99, the fitting function ΔT can be determined. n =ΔT n―1 +f(I TECn , I TECn―1 ) can meet the requirements of laser temperature control. When the fitting correlation coefficient is less than or equal to the preset threshold, temperature control is performed solely by the PID algorithm.

[0064] At the same time, the PID algorithm is used to adjust the loading current information of the TEC, control the laser temperature to reach the set working temperature, and continuously record the real-time temperature of the laser and the current information of the TEC during the PID adjustment process; according to the real-time temperature of the laser and the current information of the TEC, the relationship function F(T,I TEC ) and update the fitting function coefficient and fitting correlation coefficient R in real time during the temperature adjustment process 2 , and judge R in real time in the subsequent process 2 Once the preset error requirement is met, the temperature current fitting function is taken into account in the temperature control process of the laser.

[0065] In addition, if the preset temperature range of the laser is changed, re-fitting is required. For example, when the laser is stable at the set value of 30°C, the laser set temperature is changed to 25°C. At this time, the laser temperature will start to drop from 30°C and is in a constantly changing state. At this time, the preset relationship function will no longer apply, and the corresponding fitting correlation coefficient R 2 The value will deviate from 1. In this state, it is necessary to disable the correction function of the fitting relationship function and use only PID control to adjust the laser temperature. When the laser stabilizes at the new set 25℃ again, the re-fitted relationship function will fit the actual data under the new steady state again, and the fitting coefficient R 2 When the requirements are met again, the correction function of the fitting relationship function is turned on to control and improve the control accuracy of the laser temperature.

[0066] In summary, the laser temperature control method provided in the embodiment of the present application is to construct a temperature-current fitting function of the laser temperature and the TEC current, and fit the correlation coefficient R2 The working stability of the laser is determined by the fitting correlation coefficient R. 2 The value will deviate from 1, disable the correction function of the fitting relationship function, and only use the PID algorithm to control the laser temperature. Fitting correlation coefficient R under temperature stability 2 When it approaches 1 and its value meets the requirements, the correction function of the fitting relationship function is turned on to improve the control accuracy of the laser temperature without causing excessive burden on the temperature controller.

[0067] In some examples, controlling the regulating current of the laser to be controlled according to the temperature-current fitting function and the PID control algorithm to control the temperature of the laser to be controlled within a preset temperature range includes:

[0068] When the fitting correlation coefficient corresponding to the temperature-current fitting function is greater than a preset threshold, the real-time temperature of the laser to be controlled is obtained through the thermistor;

[0069] Determine the current preload current based on the above real-time temperature and PID control algorithm;

[0070] Determine the predicted operating temperature using the temperature-current fitting function and the current preload current;

[0071] In a case where the predicted operating temperature is within the preset temperature range, the temperature of the laser to be controlled is controlled according to the current preload current.

[0072] For example, when the fitting correlation coefficient corresponding to the temperature-current fitting function is greater than a preset threshold, the temperature-current fitting function meets the accuracy requirement. At this time, the current real-time temperature T of the laser is obtained through the thermistor. n , obtain the TEC current preload current I through the PID algorithm TECn , through the temperature current function F(T,I TEC ) is used to calculate the predicted working temperature T n+1 If the predicted operating temperature is within the preset temperature range, taking the above temperature range and accuracy as an example, for example, the laser operating temperature is set to 30°C, the preset accuracy range is ±0.01°C, when the T n+1 When the temperature value is within the range of 29.99 to 30.01°C, it can be determined that the temperature control accuracy requirement is met. At this time, the single-signature preload current is sent to the TEC for current control to control the temperature of the laser within the preset temperature range.

[0073] In some examples, if the predicted operating temperature exceeds the preset temperature range, the method further includes:

[0074] In the case where the predicted operating temperature exceeds the preset temperature range, reversely calculating the corrected loading current based on the temperature-current fitting function;

[0075] The temperature of the laser to be controlled is controlled based on the corrected loading current.

[0076] For example, if the predicted operating temperature exceeds the preset temperature range, the loading current is reversely calculated based on the preset temperature and the temperature-current fitting function. For example, if the laser operating temperature is set to 30°C and the preset accuracy range is ±0.01°C, when the predicted operating temperature T n+1 When the temperature exceeds 30.015℃, it will automatically reset T n+1 is 30.00℃, and its value is substituted into the relationship function F(T,I TEC ), that is, ΔT n =ΔT n―1 +f(I TECn , I TECn―1 ), reversely calculate the TEC correction loading current I' TECn , and the correction loading current I' TECn Provided to TEC. At the end of this temperature cycle, the laser temperature will be maintained at 30.00℃, thereby reducing the TEC load current that originally exceeded the temperature accuracy requirement by modifying the relationship function F(T,I TEC ) is calculated and the laser temperature is controlled within the accuracy range again.

[0077] In summary, the laser temperature control method proposed in the embodiment of the present application can predict the operating temperature T in advance during the temperature control process based on the temperature-current fitting function of the laser temperature and the TEC current. n+1 , if the predicted temperature T n+1 If the expected temperature accuracy range is exceeded, the reverse calculation of the relationship function can be used again to obtain a corrected TEC loading current and provide it to the TEC. In this way, the TEC loading current that originally exceeded the temperature accuracy requirement can be corrected and the laser temperature can be controlled within the accuracy range again.

[0078] In some examples, the above-mentioned method of obtaining the temperature and current fitting function of the laser to be controlled based on thermal principles includes:

[0079] Based on thermal principles, the overall heat dissipation model of the laser system is constructed in the form of functional equations;

[0080] Perform curve fitting on the above function equation according to the temperature information and current information of the laser to be controlled;

[0081] In a case where the corresponding fitting correlation coefficient of the functional equation is greater than or equal to a preset threshold, the functional equation is determined as the temperature-current fitting function.

[0082] Exemplarily, the above-mentioned function equation includes a linear function equation, a quadratic equation, a Gaussian equation, or other equations for function fitting calculation. In this application, a linear equation is used for fitting. When the corresponding fitting correlation coefficient of the function equation is greater than or equal to a preset threshold, the function equation is determined to be a temperature current fitting function.

[0083] In some examples, the method further includes:

[0084] Obtaining temperature fluctuation information of the laser to be controlled within a current preset time period;

[0085] The curve fitting of the above function equation according to the temperature information and current information of the laser to be controlled includes:

[0086] In the case that the temperature floating information meets the preset floating error requirement, curve fitting is performed on the function equation according to the temperature information and current information of the laser to be controlled.

[0087] For example, only when the temperature of the laser reaches a stable state can the linear equation be used for fitting. The principle is as follows:

[0088] Based on thermal principles, the overall heat dissipation model of the laser system is established in the form of a functional equation:

[0089] Model n: ΔT n =f n {Q 激光器n (Q 发热 ,Q 散热 ),Q TECn (I TECn ,η TEC , T ime ),Q 其他n}

[0090] Model n-1: ΔT n―1 =f n―1 {Q 激光器n―1 (Q 发热 ,Q 散热 ),Q TECn―1 (I TECn―1 ,η TEC ,Time),Q 其他n―1}

[0091] Model n and model n-1 are the temperature heat dissipation model functions of the laser system in the nth and n-1th temperature sampling periods; ΔT n and ΔT n-1Q is the difference in laser temperature between model n and model n-1 during the corresponding sampling time period; 激光器n and Q 激光器n-1 Q is the heat change of the laser itself during the corresponding sampling time period of the model n and the model n-1, including its own heating and self-heating effects; TECn and Q TECn-1 Q is the heat change caused by TEC heating or cooling in the corresponding sampling time period of the model n and model n-1. The heat change is related to the TEC's own current, heat conversion efficiency, and the action time of the TEC's own current. 其他n and Q 其他n-1 is the laser heat change caused by other factors during the corresponding sampling time period of the model n and model n-1, such as the ambient temperature;

[0092] In different temperature sampling test cycles, model n and model n-1 have different model functions f n and f n-1 , as well as their own different heat change influencing factors, etc. Such a model is very complex and is related to factors such as the external environment and the characteristics of the laser itself, making it inconvenient to use.

[0093] When the temperature of the laser system reaches or approaches a stable state, model n and model n-1 are almost in the same thermal state, and the Q 激光器 , Q 其他 and η TEC The difference is very small, and Q TEC The sampling period is the time during which the TEC current acts, and Q TEC Only with current I TEC Related, therefore:

[0094] ΔT n ―ΔT n―1 =f(I TECn )―f(I TECn―1 )

[0095] When the temperature is stable, the final temperature relationship function is obtained:

[0096] ΔT n =ΔT n―1 +f(I TECn , I TECn―1 )

[0097] Specifically, when the temperature of the laser system reaches or approaches a stable state, the temperature controller obtains output information by inputting information based on the TEC current information and temperature information in the previous sampling cycle and the TEC current information loaded in the current sampling cycle, and the laser temperature difference generated in the current sampling cycle. In the temperature-current fitting function, the current I TECn and I TECn-1 Affects the heating or cooling of TEC, causing the change of heat in the laser system, thus causing temperature change. TECn and I TECn-1 The action time is the temperature test sampling cycle time of the temperature controller, and its value is usually in the order of ms. When the temperature of the laser system reaches or approaches a stable state, the current I TEC The change in heat in the laser system caused by TEC can be approximately regarded as a linear relationship:

[0098] ΔT n =ΔT n―1 +k*(I TECn ―I TECn―1 )

[0099] Where k is the unknown function coefficient.

[0100] In summary, the laser temperature control method proposed in the embodiments of this application establishes an overall heat dissipation model of the laser system in the form of a functional equation based on thermal principles. When the temperature of the laser system reaches or approaches a steady state, the heat dissipation model function is simplified to ultimately obtain a relationship function between the laser temperature and the TEC current. This relationship function, applied to the steady state laser temperature, can be approximately viewed as a linear relationship and can be substituted into the temperature relationship function using a simple equation, thereby simplifying the calculation model.

[0101] In some examples, the method further includes:

[0102] The temperature information and the current information within a target number of cycles are obtained, wherein the target number is greater than the number of unknown coefficients corresponding to the function equation.

[0103] For example, in the process of fitting the function equation curve, it is necessary to control the target quantity of sampled temperature information and power information, such as Figure 4 As shown in the figure, the temperature sampling operation cycle of the temperature controller (named as temperature cycle nm to temperature cycle n) is divided into sampling time points (time point nm to time point n) on each fixed sampling cycle. At each time point, a set of real-time temperatures (T n-m ~T n ) and the loaded TEC current (I TECn-m ~I TECn), and based on this, the temperature change difference (ΔT n-m ~ΔT n ). In this embodiment, the relevant data within a total of m temperature cycles are used. In the process of fitting the functional relationship, it is necessary to comprehensively consider the actual performance of the temperature controller (FPGA or ARM) and the computing time loss, and specifically select the value of m. However, the value of m cannot be lower than the relationship function F(T,I TEC ). For example, if the preset relationship function is set to the form of a first-order linear equation: kx+b, which contains two unknown function coefficients k and b, then the number of sampling periods m for the fitting calculation cannot be less than 2; if the preset relationship function is set to the form of a Gaussian function equation: a×exp(―((x―b) / c)^2), which contains three unknown function coefficients a, b, and c, then the number of sampling periods m for the fitting calculation cannot be less than 3.

[0104] In some examples, the method further includes:

[0105] When the preset temperature range changes, a PID control algorithm is used to control the regulating current of the laser to be controlled so as to control the temperature of the laser to be controlled;

[0106] again performing curve fitting on the function equation according to the temperature information and current information of the laser to be controlled;

[0107] When the corresponding fitting correlation coefficient of the functional equation is again greater than or equal to the preset threshold, determining the functional equation as a second temperature-current fitting function;

[0108] The temperature of the laser to be controlled is controlled according to the second temperature-current fitting function.

[0109] For example, when the external environment changes drastically or the laser set temperature changes, for example, when the laser is stable at the set value of 30°C, the laser set temperature is changed to 25°C, and the preset temperature range corresponding to the set temperature changes, the laser temperature will start to drop from 30°C and be in a constantly changing state. At this time, the preset relationship function will no longer apply, and the corresponding fitting correlation coefficient R 2 The value will deviate from 1. In this state, it is necessary to disable the correction function of the fitting relationship function and use only PID control to adjust the laser temperature. When the laser stabilizes at the new set 25℃ again, the re-fitted relationship function will fit the actual data under the new steady state again, and the fitting coefficient R 2 When the requirements are met again, the correction function of the fitting relationship function is turned on to control and improve the control accuracy of the laser temperature.

[0110] In some examples, this can be done by Figure 3 and Figure 4 The temperature of the laser is controlled by:

[0111] S100, presetting the fitting relationship function F(T,I) between the laser operating temperature and the TEC current in a stable state in the form of unknown coefficients TEC ), and preset the relationship function fitting correlation coefficient R 2 The error range of

[0112] Step S100 specifically includes steps S1001 to S1003:

[0113] S1001. Based on thermal principles, establish the overall heat dissipation model of the laser system in the form of a functional equation:

[0114] Model n: ΔT n =f n {Q 激光器n (Q 发热 ,Q 散热 ),Q TECn (I TECn ,η TEC ,Time),Q 其他n}

[0115] Model n-1: ΔT n―1 =f n―1 {Q 激光器n―1 (Q 发热 ,Q 散热 ),Q TECn―1 (I TECn―1 ,η TEC ,Time),Q 其他n―1}

[0116] S1002, waiting for the temperature of the laser system to reach or approach a stable state. At this time, the model n and the model n-1 in step S1001 are almost in the same thermal state, and the Q 激光器 , Q 其他 and η TEC The difference is very small, and Q TEC The sampling period is the time during which the TEC current acts, and Q TEC Only with current I TEC Related, therefore:

[0117] ΔT n ―ΔT n―1 =f(I TECn )―f(I TECn―1 )

[0118] S1003. Obtain the final temperature relationship function:

[0119] ΔT n =ΔT n―1 +f(I TECn , I TECn―1 )

[0120] S200, setting the laser operating temperature and presetting the temperature accuracy range;

[0121] S300, adjusting the loading current information of the TEC through the PID algorithm to control the laser temperature to reach the set operating temperature, and continuously recording the real-time temperature of the laser and the current information of the TEC during the PID adjustment process;

[0122] S400, fitting and calculating the relationship function F(T,I) according to the real-time temperature and TEC current information of the laser TEC ) and update the fitting function coefficient and fitting correlation coefficient R in real time during the temperature adjustment process 2 ;

[0123] S500, real-time determination of the calculated fitting correlation coefficient R 2 The preset correlation coefficient error range is satisfied. If so, the process proceeds to step S600 ; otherwise, the process repeats step S300 .

[0124] S600, obtain the current real-time temperature T of the laser through the thermistor n , obtain the TEC current preload current I through the PID algorithm TECn , through the relationship function F(T,I TEC ) is used to calculate the predicted working temperature T n+1 ;

[0125] S700, determining the calculated predicted operating temperature T n+1 Whether the preset temperature accuracy range is met;

[0126] If the T n+1 If the temperature accuracy requirement is met, then the process goes to step S801; otherwise, the process goes to step S802.

[0127] S801: The TEC current preload current I obtained by the PID algorithm in step S600 is TECn Provided to TEC;

[0128] S802, correcting the predicted working temperature T in step S600 n+1 , modify it to the set working temperature value in step S200, and then use the relationship function F(T,I TEC ) Reverse calculation to obtain the TEC corrected loading current I' TECn , and the correction loading current I'TECn Provided to TEC.

[0129] S900, fitting relationship function F(T,I TEC ) According to the real-time temperature and TEC current, the fitting function coefficient and fitting correlation coefficient are updated in real time. If and only if the fitting correlation coefficient R 2 The correction function of the fitting relationship function is enabled only when the preset correlation coefficient error range is met, otherwise the temperature control and adjustment are performed only by relying on the PID algorithm.

[0130] See also Figure 5 An embodiment of the laser temperature control device in the embodiment of the present application may include:

[0131] An acquisition unit 21 is configured to acquire a temperature-current fitting function of the laser to be controlled based on thermal principles, wherein the temperature-current fitting function is a fitting function of the laser temperature and the TEC current;

[0132] The control unit 22 is used to control the regulating current of the laser to be controlled according to the temperature-current fitting function and the PID control algorithm so as to control the temperature of the laser to be controlled within a preset temperature range.

[0133] like Figure 6 As shown, an embodiment of the present application further provides an electronic device 300, comprising a memory 310, a processor 320, and a computer program 311 stored in the memory 320 and executable on the processor. When the processor 320 executes the computer program 311, the steps of any of the above-mentioned methods for controlling the temperature of the laser are implemented.

[0134] Since the electronic device introduced in this embodiment is a device used to implement a laser temperature control device in the embodiment of the present application, based on the method introduced in the embodiment of the present application, technical personnel in this field can understand the specific implementation of the electronic device of this embodiment and its various variations. Therefore, how the electronic device implements the method in the embodiment of the present application is not introduced in detail here. As long as the equipment used by technical personnel in this field to implement the method in the embodiment of the present application falls within the scope of protection to be protected by this application.

[0135] In the specific implementation process, the computer program 311 can be implemented when executed by the processor Figure 1 Any implementation manner in the corresponding embodiments.

[0136] It should be noted that, in the above embodiments, the description of each embodiment has its own focus. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant description of other embodiments.

[0137] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0138] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded computer, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0139] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0140] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0141] An embodiment of the present application further provides a computer program product, which includes computer software instructions. When the computer software instructions are executed on a processing device, the processing device executes the laser temperature control process in the corresponding embodiment.

[0142] A computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function according to the embodiment of the present application is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions can be transmitted from one website, computer, server or data center to another website, computer, server or data center via a wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) method. The computer-readable storage medium can be any available medium that a computer can store or a data storage device such as a server or data center that includes one or more available media integrated. The available medium can be a magnetic medium (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., a solid state drive (SSD)).

[0143] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0144] In the several embodiments provided in this application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of units is only a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interface, device or unit, which can be electrical, mechanical or other forms.

[0145] Units described as separate components may or may not be physically separate, and components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0146] In addition, the functional units in the various embodiments of the present application may be integrated into a single processing unit, or each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0147] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the various embodiments of the present application. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0148] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A laser temperature control method, characterized in that: include: Obtaining a temperature-current fitting function of the laser to be controlled based on thermal principles, wherein the temperature-current fitting function is a fitting function of the laser temperature and the TEC current; controlling the regulating current of the laser to be controlled according to the temperature-current fitting function and the PID control algorithm to control the temperature of the laser to be controlled within a preset temperature range; The step of controlling the regulating current of the laser to be controlled according to the temperature-current fitting function and the PID control algorithm to control the temperature of the laser to be controlled within a preset temperature range includes: When the fitting correlation coefficient corresponding to the temperature-current fitting function is less than or equal to a preset threshold, a PID control algorithm is used to control the regulating current of the laser to be controlled so as to control the temperature of the laser to be controlled within a preset temperature range; When the fitting correlation coefficient corresponding to the temperature-current fitting function is greater than a preset threshold, obtaining the real-time temperature of the laser to be controlled through the thermistor; Determine the current preload current according to the real-time temperature and the PID control algorithm; Determining a predicted operating temperature using the temperature-current fitting function and the current preload current; When the predicted operating temperature is within the preset temperature range, controlling the temperature of the laser to be controlled according to the current preload current; The method of obtaining the temperature and current fitting function of the laser to be controlled based on thermal principles includes: Based on thermal principles, the overall heat dissipation model of the laser system is constructed in the form of functional equations; Performing curve fitting on the functional equation according to temperature information and current information of the laser to be controlled; When the corresponding fitting correlation coefficient of the functional equation is greater than or equal to a preset threshold, the functional equation is determined as the temperature-current fitting function.

2. The method according to claim 1, wherein Also includes: In the case where the predicted operating temperature exceeds the preset temperature range, reversely calculating the corrected loading current based on the temperature-current fitting function; The temperature of the laser to be controlled is controlled based on the corrected loading current.

3. The method according to claim 1, wherein The functional equation includes a linear functional equation; The method further comprises: Acquiring temperature fluctuation information of the laser to be controlled within a current preset time period; The curve fitting of the function equation according to the temperature information and current information of the laser to be controlled includes: When the temperature floating information meets the preset floating error requirement, curve fitting is performed on the function equation according to the temperature information and current information of the laser to be controlled.

4. The method according to claim 1, wherein Also includes: Acquire temperature information and current information within a target number of cycles, wherein the target number is greater than the number of unknown coefficients corresponding to the function equation.

5. The method according to claim 1, wherein Also includes: When the preset temperature range changes, a PID control algorithm is used to control the regulating current of the laser to be controlled so as to control the temperature of the laser to be controlled; again performing curve fitting on the function equation according to the temperature information and current information of the laser to be controlled; When the corresponding fitting correlation coefficient of the functional equation is again greater than or equal to the preset threshold, determining the functional equation as a second temperature-current fitting function; The temperature of the laser to be controlled is controlled according to the second temperature-current fitting function.

6. A laser temperature control device, applying the laser temperature control method according to any one of claims 1 to 5, characterized in that: include: An acquisition unit, configured to acquire a temperature-current fitting function of the laser to be controlled based on thermal principles, wherein the temperature-current fitting function is a fitting function of the laser temperature and the TEC current; A control unit is used to control the regulating current of the laser to be controlled according to the temperature-current fitting function and the PID control algorithm to control the temperature of the laser to be controlled within a preset temperature range.

7. An electronic device comprising: A memory and a processor, wherein the processor is configured to implement the steps of the laser temperature control method according to any one of claims 1 to 5 when executing a computer program stored in the memory.

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