Method and device for screening tuning range of narrow linewidth laser

Abstract

The invention relates to a narrow linewidth laser tuning range screening method and device, and belongs to the technical field of optical fiber communication. The method comprises the following steps: step 1, linearly adjusting the temperature of a narrow linewidth laser, and synchronously collecting wavelength and optical power data; step 2, when mode hopping of the optical power is detected, recording temperature-wavelength-power data before and after mode hopping and resetting; step 3, refining temperature stepping in a mode hopping temperature interval by adopting a successive approximation method, and positioning a maximum tuning wavelength value; 4, comparing the actually measured tuning range with a preset threshold value, and outputting a judgment result whether the tuning range is qualified or not; the device comprises a processor module, a current control circuit, a temperature control circuit, an optical power detection circuit and a wavelength detection module, a complete screening device is constructed, the current control module, the temperature control module, the optical power detection module, the wavelength detection module and the processing module are integrated, a closed loop from the method to hardware is achieved, full-automatic screening is supported, and the screening operability is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to a narrow linewidth laser tuning range screening method and device, belonging to the field of optical fiber communication technology. BACKGROUND

[0002] In optical communication, in addition to being stable at the center wavelength, narrow linewidth lasers must also have a certain wavelength tuning range when they are at the center wavelength. For example, Chinese Patent Publication No. CN116131096A discloses a wide-tuning narrow-linewidth semiconductor narrow-linewidth laser, which uses Fano resonance between a micro-ring resonator and a U-shaped waveguide and vernier scale effect between micro-ring resonators to achieve tuning function, and uses a Mach-Zehnder interferometer to suppress side modes in the transmission spectrum of the micro-ring resonator, thereby improving wavelength selectivity. Narrow linewidth, frequency stability and wide spectral range of the output laser are achieved. Wavelength tuning change is achieved by changing the temperature control temperature inside the narrow linewidth laser. Under the same mode segment, the tuning of the same wavelength of the narrow linewidth laser must correspond to a unique temperature point. When the narrow linewidth laser jumps the mode, the output power and wavelength will change, and the maximum tuning range of the narrow linewidth laser is the wavelength value before the jump. In order to ensure the correctness of optical communication, the user needs to screen the wavelength tuning range of the narrow linewidth laser.

[0003] The current wavelength tuning screening is achieved by manually adjusting the temperature control temperature of the narrow linewidth laser gradually in the same temperature control direction until the narrow linewidth laser jumps the mode. The wavelength meter is used to observe that the wavelength of the narrow linewidth laser jumps, and the final wavelength before the jump is the maximum up-tuning or down-tuning range. Then the temperature control direction is adjusted in the opposite direction. The manual adjustment of the wavelength for screening greatly consumes manpower and resources.

[0004] Therefore, there is an urgent need for a narrow linewidth laser tuning range screening method and device that can automatically screen the narrow linewidth laser that meets the tuning requirements and save manpower and resources. SUMMARY

[0005] The purpose of the present application is to provide a narrow linewidth laser tuning range screening method and device, which connects the narrow linewidth laser to the control circuit, automatically controls the maximum tuning value of the narrow linewidth laser, compares it with the tuning index, and finally screens the narrow linewidth laser that meets the tuning requirements.

[0006] The narrow linewidth laser tuning range screening method provided by the present application comprises:

[0007] Step 1: linearly adjust the temperature of the narrow linewidth laser, and synchronously collect wavelength and optical power data;

[0008] Step 2, when detecting that the optical power jumps, record the temperature-wavelength-power data before and after the jump and reset;

[0009] Step 3, in the jump temperature interval, use the successive approximation method to refine the temperature step, and locate the maximum tuning wavelength value;

[0010] Step 4, compare the measured tuning range with the preset threshold, and output the qualification determination result.

[0011] Through the process of linear temperature adjustment, jump detection, successive approximation positioning of the maximum tuning wavelength, and threshold comparison, the automatic and high-precision screening of the tuning range is realized, the error caused by manual intervention is avoided, the screening efficiency and reliability are improved, and manpower and material resources are saved.

[0012] Here, the reset is that the narrow linewidth laser is restarted, and the wavelength returns to the original center wavelength value.

[0013] Preferably, the linear adjustment of the temperature of the narrow linewidth laser in step 1 is specifically adjusting the temperature by a step temperature ΔT = 0.5-1℃.

[0014] The temperature step is set to 0.5-1℃ (including 0.5℃ and 1℃), which takes into account the temperature adjustment accuracy and efficiency: too large a step may miss the jump point, and too small a step will reduce the efficiency. The step of 0.5-1℃ optimizes the efficiency of the screening process while ensuring data density.

[0015] Preferably, the determination condition of the jump in step 2 is:

[0016] the power change amount |ΔP|≥ΔPmax,

[0017] the wavelength change amount |Δλ|≥Δλmax,

[0018] the wavelength after the jump is in the non-edge tuning range of another mode section;

[0019] wherein ΔPmax is the allowable range of power change, and Δλmax is the allowable range of wavelength change.

[0020] The determination criteria of the jump (power / wavelength change amount exceeding the threshold and wavelength being in the non-edge tuning range) are defined, which avoids false positives caused by accidental noise or unstable edge tuning, improves the accuracy of jump detection, and provides a reliable basis for subsequent screening.

[0021] Preferably, step 2 specifically includes:

[0022] Step 201, initialization

[0023] Create an empty list hops to store the positions of the detected jump events;

[0024] Step 202, traversing the data sequence

[0025] From the second data point, i.e. index i = 1, compare the power and wavelength values of the current time i and the previous time i-1 in turn;

[0026] Step 203, calculating the change

[0027] Calculate the power change: |ΔP| = |current power - previous power|

[0028] Calculate the wavelength change: |Δλ| = |current wavelength - previous wavelength|

[0029] Step 204, jump condition judgment

[0030] If the following two conditions are met at the same time, it is considered that a mode jump may occur:

[0031] Power jump: |ΔP| ≥ ΔPmax

[0032] Wavelength jump: |Δλ| ≥ Δλmax

[0033] Step 205, non-edge range verification

[0034] Verify whether the current wavelength is in the non-edge range of normal tuning of the narrow linewidth laser, and if it passes the verification, add the current index i to the mode jump list hops;

[0035] Step 206, return result

[0036] Finally return the list of index positions hops of all detected mode jump events.

[0037] Through the process design of initialization, data traversal, change calculation, condition judgment and non-edge verification, automatic detection and positioning of mode jump events are realized, reducing the complexity of manual analysis and improving the efficiency and consistency of mode jump detection.

[0038] Preferably, the step 3 specifically comprises:

[0039] Step 301, finding the upper limit of tuning

[0040] Coarse adjustment stage:

[0041] Start from the current temperature Tstart, gradually increase the temperature ΔT, and measure the wavelength λ;

[0042] If the wavelength continues to increase, record the current temperature Thigh and the wavelength λhigh_temp.

[0043] When the wavelength no longer increases, stop coarse adjustment and enter fine adjustment;

[0044] Fine adjustment stage:

[0045] In the temperature range [Tlow, Thigh], calculate the intermediate temperature Tmid = (Tlow + Thigh) / 2;

[0046] Adjust to Tmid, measure the wavelength λmid.

[0047] Adjust to Tmid + εtemp, measure λmid_plus.

[0048] If λmid_plus > λmid, it means that there is a larger wavelength in the higher temperature direction, update Tlow = Tmid; otherwise, update Thigh = Tmid;

[0049] Repeat until the temperature range difference < ε, at this time the wavelength corresponding to Thigh is λhigh;

[0050] Step 302, find the lower limit of tuning

[0051] Similar to step 301, but in the direction of reducing temperature, find the minimum value of the wavelength;

[0052] Where ε is the accuracy.

[0053] The coarse-fine adjustment combined successive approximation method is used to locate the maximum tuning wavelength: coarse adjustment quickly narrows the range, and fine adjustment accurately approaches the limit temperature point through bisection method, avoiding the omission or redundancy caused by linear step, and significantly improving the accuracy and efficiency of the tuning range positioning.

[0054] Preferably, whether the step 4 is qualified is determined as follows:

[0055] Calculate the required range: λupper = λcenter + Δ, λlower = λcenter - Δ;

[0056] If λhigh ≥ λupper and λlow ≤ λlower, the tuning range is qualified; otherwise, it is not qualified;

[0057] Where λcenter is the center wavelength, and Δ is the tuning range.

[0058] By directly comparing the preset tuning range (λcenter ± Δ) with the measured range (λhigh / λlow), an objective and quantitative qualification criterion is provided, the automatic output of the screening result is realized, and the error of subjective judgment is avoided.

[0059] The narrow linewidth laser tuning range screening device provided by the application comprises:

[0060] Current control circuit: for controlling the power supply of the narrow linewidth laser, and triggering the reset signal when mode hopping is detected;

[0061] Temperature control circuit: for wavelength tuning control of the narrow linewidth laser;

[0062] Optical power detection circuit: for collecting the output optical power of the narrow linewidth laser;

[0063] Wavelength detection module: for real-time acquisition of the current wavelength of the narrow linewidth laser;

[0064] Processor module: connected to the current control circuit, temperature control circuit, optical power detection circuit and wavelength detection module, for executing the above-mentioned narrow linewidth laser tuning range screening method to screen the narrow linewidth laser tuning range.

[0065] A complete screening device is constructed, integrating current control, temperature control, optical power detection, wavelength detection and processing modules, realizing a closed loop from method to hardware, supporting full-automatic screening, and improving the operability of screening.

[0066] Preferably, the processor module controls the on-off of the narrow linewidth laser current by enabling the base level of the transistor in the current control circuit, and when the narrow linewidth laser is turned off and turned on again, the narrow linewidth laser is restored to the center wavelength value in combination with TEC temperature control.

[0067] The on-off control of the narrow linewidth laser current is realized by controlling the base level of the transistor, and the narrow linewidth laser automatically restores the center wavelength after reset, simplifying the reset operation after mode hopping and improving the response speed and stability of the device.

[0068] Preferably, the processor module controls the operating temperature of the actual narrow linewidth laser by comparing the digital-to-analog converter of the temperature control circuit with the actual operating temperature through an operational amplifier, and continuously adjusts the temperature control module of the narrow linewidth laser to control the operating temperature of the narrow linewidth laser to be consistent with the control temperature.

[0069] The actual temperature and the control temperature are compared by using a digital-to-analog converter and an operational amplifier, realizing closed-loop temperature control, ensuring accurate and stable temperature of the narrow linewidth laser, avoiding the influence of temperature fluctuation on the tuning range, and improving the temperature control precision and screening reliability.

[0070] Preferably, the optical power detection circuit includes a photodiode and a transimpedance amplifier, which converts the output optical power of the narrow linewidth laser into a voltage signal and transmits it to the processor module.

[0071] The light power detection circuit combined with a photoelectric diode and a transimpedance amplifier converts a weak light signal into a high signal-to-noise ratio voltage signal, improves the sensitivity and accuracy of light power detection, and provides a reliable data basis for mode jump determination.

[0072] Compared with the prior art, the narrow linewidth laser tuning range screening method and device has the following advantages:

[0073] 1. Significant improvement in screening accuracy and reliability

[0074] Accurate identification of mode jump events: By setting a power change threshold (ΔPmax) and a wavelength change threshold (Δλmax), combined with verification of the non-edge tuning range, false positives are effectively filtered out, ensuring that recording is triggered only when mode jump occurs, and avoiding false detection caused by noise or temporary fluctuations.

[0075] Precise positioning of the tuning boundary: The successive approximation method is used to refine the temperature step within the mode jump interval, and the temperature range is dynamically reduced through coarse-fine two-stage adjustment, finally positioning the maximum / minimum tuning wavelength with high precision ε. Compared with the traditional linear scanning method, the number of measurement points can be reduced and the boundary positioning accuracy can be improved.

[0076] 2. Optimization of screening efficiency and automation level

[0077] Linear adjustment and synchronous acquisition: Through step temperature adjustment and real-time data acquisition (step 1), continuous monitoring of the tuning process is achieved, avoiding discontinuous errors caused by manual intervention.

[0078] Reset mechanism ensures stability: After mode jump occurs, it is automatically reset to the center wavelength (step 2), ensuring that subsequent measurements are not affected by previous mode jumps, improving test repeatability.

[0079] 3. Product quality control and cost reduction

[0080] Threshold comparison determination: Directly compare the measured tuning range with the preset threshold (λcenter±Δ) to quickly output pass / fail conclusions, avoiding subjective judgment and ensuring that the tuning performance of the narrow linewidth laser meets the design requirements.

[0081] Integrated device design: Through the processor module, current control, temperature control, light power and wavelength detection are integrated to realize full automation of the screening process, reducing manual operation time and equipment dependence, and reducing production costs.

[0082] 4. Hardware and algorithm optimization

[0083] Temperature control closed loop: A temperature control loop is constructed using a digital-to-analog converter and an operational amplifier to ensure that the actual temperature is consistent with the set value, improving the stability of temperature adjustment.

[0084] High-sensitivity optical power detection: The combination of photodiode and transimpedance amplifier converts the optical signal into a voltage signal, enhancing the detection capability of weak optical power changes and supporting the sensitivity of mode hopping determination.

[0085] In summary, this technical solution, through algorithm optimization and hardware integration, solves the problems of low accuracy, poor efficiency, and excessive human interference in traditional screening methods, providing an efficient and reliable quality control means for the large-scale production of narrow-linewidth lasers. Attached Figure Description

[0086] Figure 1 This is a structural block diagram of a narrow linewidth laser tuning range screening device according to the present invention;

[0087] Figure 2 This is a circuit diagram of a current control circuit according to the present invention;

[0088] Figure 3 This is a circuit diagram of a temperature control circuit according to the present invention;

[0089] Figure 4 This is a circuit diagram of an optical power detection circuit according to the present invention;

[0090] Figure 5 This is a flowchart illustrating the operation of a narrow linewidth laser tuning range screening device according to the present invention. Detailed Implementation

[0091] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0092] Example 1

[0093] like Figures 1-4 As shown, this embodiment discloses a narrow linewidth laser tuning range screening device, comprising:

[0094] Current control circuit: A MOSFET driving circuit is used. The gate voltage of MOSFET Q1 is a fixed value, that is, the driving current of the narrow linewidth laser is a unique fixed value. During reset, the narrow linewidth laser is turned off by pulling down the base level of transistor Q2. After power-on, the laser is restored to the center wavelength value by combining TEC temperature control.

[0095] Temperature control circuit: Includes PID control module and TEC cooling chip, outputs control voltage through 16-bit DAC, drives TEC through operational amplifier U3, with an accuracy of ±0.01℃.

[0096] Light power detection circuit: output light 1 / 100 of the light splitting access photoelectric transducer PD1, and then convert the current into voltage, access the ADC module voltage acquisition, processor according to the ADC acquisition value calculation light power value.

[0097] Wavelength detection module: using a computer through the wavelength meter real-time access to the current wavelength of narrow linewidth laser.

[0098] Processor module: using STM32H743 master chip, running FreeRTOS real-time operating system, sampling frequency is set to 10kHz; With the computer through wired or wireless communication to realize information exchange, to determine whether the narrow linewidth laser produces jump mode, to capture the final wavelength tuning maximum value of narrow linewidth laser.

[0099] As shown in Figure 5 the working process of the narrow linewidth laser tuning range screening device is as follows:

[0100] 1. The processor module can control the on-off of the narrow linewidth laser through the current control circuit. After the narrow linewidth laser produces jump mode, reset the narrow linewidth laser; the processor controls the operating temperature of the narrow linewidth laser through the temperature controller, and then controls the wavelength tuning of the narrow linewidth laser to find the maximum tuning range of the wavelength.

[0101] 2. The processor module detects the light power of the narrow linewidth laser through the light detection module. The output power of the narrow linewidth laser is in the same mode segment, and the change of its power makes the continuous smoothness change with the adjustment of the wavelength, but when the jump mode occurs, the power of the narrow linewidth laser will jump relatively sharply, at this time, it is judged whether the wavelength tuning of the narrow linewidth laser when the jump mode occurs is greater than or equal to the required tuning range value. The center wavelength region of the narrow linewidth laser, the gain medium realizes the highest power output near the center wavelength. For example, the output power of the 1550nm tunable narrow linewidth laser can reach 10.0dbm-13.0dbm at the center wavelength, and when the wavelength of the narrow linewidth laser deviates from the center to the gain edge bandwidth, the gain coefficient decreases significantly, resulting in power attenuation. After the narrow linewidth laser jumps, the wavelength of the narrow linewidth laser will be in another mode segment of non-edge tuning range, and the power of the narrow linewidth laser will change sharply.

[0102] Table 1 wavelength and power change corresponding table

[0103] Serial number Wavelength corresponding temperature value / °C Wavelength / nm Power value / dBm 1 24.5 1550.5600 12.95 2 25.5 1550.5605 12.20 3 26.4 1550.5610 11.45 4 27.5 1550.5615 10.7 5 28.6 1550.5621 9.17 6 29.4 1550.5585 (jump film is generated) 11.85 (power reverse sharp change)

[0104] As can be seen, the narrow linewidth laser produces jump film phenomenon between 28.6℃ and 29.4℃, then the processor will find the working temperature point of jump mode again according to this interval.

[0105] 3. The processor finds the temperature point of the maximum wavelength tuning value of the narrow linewidth laser by successive approximation, and the processor informs the computer that the maximum tuning wavelength value of the narrow linewidth laser is obtained at this time, and the computer records the value and compares it with the required maximum tuning wavelength value to determine whether it is qualified. For example, the central wavelength value of the narrow linewidth laser is λ1=1540.56 nm, and the required tuning range is ±0.05 nm, so the up and down tuning ranges of the narrow linewidth laser should be greater than 1540.61 nm and less than 1540.51 nm, respectively. If the wavelength tuning range of the narrow linewidth laser is 1540.60 nm-1540.52 nm, the narrow linewidth laser tuning range is unqualified, and if the wavelength tuning range of the narrow linewidth laser is 1540.62 nm-1540.50 nm, the narrow linewidth laser tuning range is qualified.

[0106] 4. After finding the wavelength tuning range on one side, the above-mentioned 123-step operation is repeated to find whether the maximum wavelength tuning value on the other side (up or down tuning) meets the standard.

[0107] Example 2

[0108] The embodiment discloses a narrow linewidth laser tuning range screening method, comprising:

[0109] Step 1, linearly adjusting the temperature of the narrow linewidth laser, and synchronously collecting wavelength and optical power data;

[0110] Step 2, when the optical power jump is detected, recording the temperature-wavelength-power data before and after the jump and resetting;

[0111] Step 3, refining the temperature step by using the successive approximation method in the jump temperature interval, and positioning the maximum tuning wavelength value;

[0112] Step 4, comparing the measured tuning range with the preset threshold value, and outputting the qualified determination result.

[0113] Specifically as follows:

[0114] 1. Data acquisition and pretreatment

[0115] The optical power detection circuit and the wavemeter are used to collect data in real time.

[0116] 2. Threshold setting

[0117] According to the specification book of the narrow linewidth laser, ΔPmax and Δλmax are set, and the mode segment boundary is defined (for example, 1550.55 nm to 1550.57 nm is a mode segment).

[0118] 3. Jump detection algorithm

[0119] 3.1 Initialization

[0120] Create an empty list hops to store the detected hop event positions;

[0121] 3.2 Traverse the data sequence

[0122] From the second data point, that is, index i = 1; compare the power and wavelength values of the current time i and the previous time i-1 in turn; the step temperature ΔT between the current time i and the previous time i-1 is 1℃;

[0123] 3.3 Calculate the change

[0124] Calculate the power change: |ΔP| = |current power - previous power|

[0125] Calculate the wavelength change: |Δλ| = |current wavelength - previous wavelength|

[0126] 3.4 Hop condition judgment

[0127] If the following two conditions are met at the same time, it is considered that a mode hop may occur:

[0128] Power jump: |ΔP| ≥ ΔPmax

[0129] Wavelength jump: |Δλ| ≥ Δλmax

[0130] 3.5 Non-edge range verification

[0131] Verify whether the current wavelength is in the non-edge range of normal tuning of the narrow linewidth laser, if it passes the verification, add the current index i to the mode hop list hops;

[0132] 3.6 Return result

[0133] Finally return the list of index hops of all detected mode hop events.

[0134] Code example:

[0135] defdetect_mode_hop(power_series,wavelength_series,delta_p,delta_lambda):

[0136] hops=[]

[0137] foriinrange(1,len(power_series)):

[0138] dp=abs(power_series[i]-power_series[i-1])

[0139] dl = abs(wavelength_series[i] - wavelength_series[i-1])

[0140] if dp >= delta_p and dl >= delta_lambda:

[0141] # Verify if in non-edge tuning range

[0142] if is_non_edge(wavelength_series[i]):

[0143] hops.append(i)

[0144] return hops

[0145] 4. Tuning range verification and adjustment

[0146] After mode hopping, calculate the deviation of current wavelength from the target tuning range.

[0147] If the deviation is out of the allowed range, refine the search for the stable operating point within the mode hopping interval with smaller steps (e.g., 0.1°C) through the temperature control module (TEC). The specific steps are as follows:

[0148] 4.1 Initialization parameters

[0149] Input: center wavelength λcenter, tuning range Δ, initial temperature adjustment step ΔTinitial, precision ε;

[0150] Output: maximum wavelength λhigh, minimum wavelength λlow;

[0151] 4.2 Find the upper limit of tuning

[0152] Coarse adjustment stage:

[0153] Start from the current temperature Tstart, gradually increase the temperature ΔTinitial, and measure the wavelength λ;

[0154] If the wavelength continues to increase, record the current temperature Thigh and the wavelength λhigh_temp.

[0155] When the wavelength no longer increases, stop the coarse adjustment and enter the fine adjustment;

[0156] Fine adjustment stage:

[0157] Calculate the intermediate temperature Tmid = (Tlow + Thigh) / 2 within the temperature range [Tlow, Thigh];

[0158] Adjust to Tmid and measure the wavelength λmid.

[0159] Adjust to Tmid+εtemp, measure wavelength λmid_plus.

[0160] If λmid_plus>λmid, it means there is a larger wavelength in the higher temperature direction, update Tlow=Tmid; otherwise update Thigh=Tmid;

[0161] Repeat until the temperature range difference <ε, at this time the wavelength corresponding to Thigh is λhigh;

[0162] 4.3 Finding the lower limit of tuning

[0163] Similar to 4.2, but in the direction of reducing temperature, find the minimum wavelength.

[0164] 5. Verification of eligibility

[0165] Calculate the required range: λupper=λcenter+Δ, λlower=λcenter–Δ;

[0166] If λhigh≥λupper and λlow≤λlower, the tuning range is eligible; otherwise it is not eligible.

[0167] For example

[0168] Input: λcenter=1540.56nm, Δ=0.05nm, ΔTinitial=0.5℃, ε=0.01℃.

[0169] Output:

[0170] If λhigh=1540.62nm(≥1540.61nm), λlow=1540.50nm(≤1540.51nm)→eligible.

[0171] If λhigh=1540.60nm(<1540.61nm), λlow=1540.52nm(>1540.51nm)→not eligible.

[0172] The above is only a preferred specific embodiment of the present embodiment, but the protection scope of the present embodiment is not limited thereto, any person skilled in the art within the technical scope disclosed by the present embodiment, according to the technical scheme and inventive concept of the present embodiment, equivalent replacement or change, should be covered within the protection scope of the present embodiment.

Claims

1. A method for screening the tuning range of a narrow linewidth laser, characterized in that, include: Step 1: Linearly adjust the temperature of the narrow linewidth laser while simultaneously acquiring wavelength and optical power data; Step 2: When mode hopping of optical power is detected, record the temperature-wavelength-power data before and after mode hopping and reset; Step 3: Within the mode-hopping temperature range, refine the temperature step using a successive approximation method to locate the maximum tuning wavelength value; Step 4: Compare the measured tuning range with the preset threshold and output the result of whether it is qualified.

2. The method for screening the tuning range of a narrow linewidth laser according to claim 1, characterized in that, In step 1, the linear adjustment of the narrow linewidth laser temperature is specifically achieved by adjusting the temperature in steps of ΔT = 0.5-1℃.

3. The method for screening the tuning range of a narrow linewidth laser according to claim 1, characterized in that, The determination condition for mode skipping in step 2 is as follows: The change in power |ΔP| ≥ ΔPmax, The wavelength change |Δλ| ≥ Δλmax After the wavelength jump, it falls within the non-edge tuning range of another mode segment; Where ΔPmax is the allowable range of power variation, and Δλmax is the allowable range of wavelength variation.

4. The method for screening the tuning range of a narrow linewidth laser according to claim 3, characterized in that, Step 2 specifically includes: Step 201, Initialization Create an empty list hops to store the locations of detected hop events; Step 202: Traverse the data sequence Starting from the second data point, i.e., index i = 1; compare the power and wavelength values ​​at the current time i with those at the previous time i-1; Step 203: Calculate the change Calculate the power change: |ΔP| = |current power - previous power| Calculate the wavelength change: |Δλ| = |current wavelength - previous wavelength| Step 204: Judgment of transition conditions If both of the following conditions are met simultaneously, then mode skipping is considered to be possible: Power jump: |ΔP| ≥ ΔPmax Wavelength jump: |Δλ| ≥ Δλmax Step 205: Non-edge range verification Verify whether the current wavelength is within the non-edge range of normal tuning of the narrow linewidth laser. If the verification passes, add the current index i to the mode hopping list hops. Step 206, Return Results Finally, it returns a list of indexes of all detected hop events, hops.

5. The method for screening the tuning range of a narrow linewidth laser according to claim 1, characterized in that, Step 3 specifically includes: Step 301: Find the upper limit of tuning Coarse adjustment stage: Starting from the current temperature Tstart, gradually increase the temperature ΔT and measure the wavelength λ; If the wavelength continues to increase, record the current temperature Thigh and wavelength λhigh_temp. When the wavelength stops increasing, stop coarse adjustment and start fine adjustment; Fine-tuning stage: Within the temperature range [Tlow, Thigh], calculate the intermediate temperature Tmid = (Tlow + Thigh) / 2; Adjust to Tmid and measure wavelength λmid. Adjust to Tmid+εtemp and measure λmid_plus. If λmid_plus > λmid, it means that a larger wavelength exists in the direction of higher temperature, so update Tlow = Tmid; otherwise, update Thigh = Tmid. Repeat until the temperature range difference is less than ε, at which point the wavelength corresponding to Thigh is λhigh; Step 302: Find the lower limit of tuning Similar to step 301, but the direction is to decrease the temperature and find the minimum wavelength; Where ε represents precision.

6. The method for screening the tuning range of a narrow linewidth laser according to claim 5, characterized in that, The qualification determination in step 4 is as follows: Calculation requirements: λupper = λcenter + Δ, λlower = λcenter – Δ; If λhigh≥λupper and λlow≤λlower, then the tuning range is acceptable; otherwise, it is unacceptable. Where λcenter is the center wavelength and Δ is the tuning range.

7. A narrow linewidth laser tuning range screening device, characterized in that, include: Current control circuit: used to control the power supply to the narrow linewidth laser and trigger a reset signal when mode skipping is detected; Temperature control circuit: used for wavelength tuning control of narrow linewidth lasers; Optical power detection circuit: used to acquire the output optical power of a narrow linewidth laser; Wavelength detection module: used to acquire the current wavelength of the narrow linewidth laser in real time; Processor module: Connects current control circuit, temperature control circuit, optical power detection circuit and wavelength detection module, used to execute the narrow linewidth laser tuning range screening method according to any one of claims 1-6, and to screen the narrow linewidth laser tuning range.

8. The narrow linewidth laser tuning range screening device according to claim 7, characterized in that, The processor module controls the switching of the narrow linewidth laser current by adjusting the base level of the transistor in the enable current control circuit. When the narrow linewidth laser is turned off and then turned on again, it will return to the center wavelength value.

9. A narrow linewidth laser tuning range screening device according to claim 7, characterized in that, The processor module compares the actual operating temperature of the narrow-linewidth laser with the digital-to-analog converter of the temperature control circuit via an operational amplifier, and continuously adjusts the temperature control module of the narrow-linewidth laser to ensure that the operating temperature of the narrow-linewidth laser matches the control temperature.

10. A narrow linewidth laser tuning range screening device according to claim 7, characterized in that, The optical power detection circuit includes a photodiode and a transimpedance amplifier, which convert the output optical power of the narrow linewidth laser into a voltage signal and transmit it to the processor module.

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