A method for quickly testing and calibrating the wavelength of an sgdbr semiconductor tunable laser

Abstract

This invention discloses a rapid testing and calibration method for the wavelength of SGDBR semiconductor tunable lasers, belonging to the field of semiconductor laser testing technology. This invention aims to solve the technical problems of long testing time, excessive redundant data, and low efficiency in existing full-matrix point-by-point testing methods. This invention first fixes the front and rear gratings at two boundary values ​​within their respective current adjustment ranges, and performs a full-range zigzag boundary scan on the other grating to collect boundary wavelength data. Through three-dimensional data model analysis, wavelength jump intervals are identified, determining the range of each tuning channel and the effective core interval based on the channel centerline. Finally, within the core interval, a fine scan is performed by synchronously adjusting the dual gratings with smaller step values, and the current-wavelength correspondence is obtained through independent data fitting for each channel. This invention reduces the number of test points by more than 90%, shortens the testing and calibration time for a single device from over 360 minutes to less than 30 minutes, and improves overall efficiency by more than 10 times, while maintaining calibration accuracy comparable to traditional methods. It can be widely applied in fields such as optical communication and lidar.

Description

Technical Field

[0001] This invention belongs to the technical field of semiconductor laser testing, and particularly relates to a wavelength tuning calibration technique for semiconductor tunable lasers. Background Technology

[0002] In fields such as optical communication, lidar, and spectral analysis, sampled grating distributed Bragg reflector (SGDBR) semiconductor tunable lasers have become core light source devices due to their wide wavelength tuning range and high wavelength stability. Accurate testing and calibration of their wavelength tuning performance is a crucial step in the entire process of device production and application. Wavelength tuning of SGDBR semiconductor tunable lasers is achieved by applying different driving currents to two sets of sampling gratings. There is a one-to-one correspondence between the grating driving current and the output wavelength. Only by determining the complete wavelength tuning range and the precise current-wavelength matching relationship through systematic testing and calibration can the device achieve stable and accurate wavelength output in practical applications.

[0003] In existing technologies, the testing and calibration of SGDBR semiconductor tunable lasers generally adopts a full-matrix point-by-point testing method: a full-domain scan of the driving current of the front and rear gratings is performed using a fixed current step. For example, when the driving current adjustment range of the front and rear gratings is 0-50mA and the step current is 0.5mA, each point in a 100×100 matrix needs to be powered on and the corresponding output wavelength tested, accumulating up to 10,000 test points (the total number of test points is directly related to the current step value and the current test range). This testing method has significant drawbacks: First, the testing and calibration time is too long, failing to meet the high-efficiency testing requirements of mass production and becoming a key bottleneck for capacity improvement; second, there are too many redundant test points, with full-domain point-by-point testing including a large amount of invalid test data from non-core tuning ranges, resulting in a serious waste of testing resources; third, data processing efficiency is low, as the analysis and screening of massive amounts of test data often requires manual intervention, further reducing overall calibration efficiency. In summary, the cumbersome and inefficient nature of the traditional full-matrix point-by-point testing method is no longer suitable for the large-scale production needs of SGDBR semiconductor tunable lasers, and there is an urgent need for an efficient, accurate, and rapid testing and calibration method. Summary of the Invention

[0004] To address the technical problem of low testing and calibration efficiency of SGDBR semiconductor tunable lasers, this invention proposes a rapid testing and calibration method for the wavelength of SGDBR semiconductor tunable lasers. This method uses a host computer to precisely control the laser drive current and a wavelength meter to efficiently collect output wavelength data. It innovatively adopts a technical route that combines a zigzag boundary scanning test with three-dimensional data model analysis and fine calibration of the core area, which significantly reduces the number of test points, significantly shortens the testing and calibration time, and improves the automation level of data processing and calibration accuracy. This method can effectively meet the high-efficiency testing requirements of SGDBR semiconductor tunable lasers in the mass production stage.

[0005] To achieve the above objectives, the technical solution of the present invention is implemented as follows:

[0006] A rapid testing and calibration method for the wavelength of an SGDBR semiconductor tunable laser, wherein the SGDBR semiconductor tunable laser comprises a front grating and a rear grating, comprising the following steps:

[0007] (1) Set the driving current adjustment range and basic test parameters for the front and rear grating regions; construct a communication link between the host computer and the laser driving module and wavelength detection device so that the host computer can independently adjust the driving current of each grating region and receive the laser output wavelength data collected by the wavelength detection device in real time.

[0008] (2) Boundary contour scanning test: The driving current of the front grating area is fixed at two boundary values ​​within its adjustment range, and the driving current of the rear grating area is subjected to full-range scanning test within its adjustment range, and the corresponding output wavelength data is collected synchronously; The driving current of the rear grating area is fixed at two boundary values ​​within its adjustment range, and the driving current of the front grating area is subjected to full-range scanning test within its adjustment range, and the corresponding output wavelength data is collected synchronously.

[0009] (3) Tuning channel range identification: The boundary scan data collected in step (2) is processed to identify the wavelength change interval as the boundary of the tuning channel; based on the identified channel boundary, the current-wavelength mapping range and effective tuning core interval of each tuning channel are determined.

[0010] (4) Precise calibration: Within the effective tuning core range of each tuning channel determined in step (3), the driving current of the front grating and rear grating regions is finely scanned and tested, and the corresponding current-wavelength matching data is collected; the current-wavelength correspondence is obtained through data fitting, and the wavelength tuning performance calibration of the SGDBR semiconductor tunable laser is completed.

[0011] In step (1), the driving current adjustment range of the front grating and the rear grating is independently I. min -I max The current step value is ΔI; where I min for 0mA-2mA, I max The range is 30mA-80mA, and ΔI is 0.1-2mA.

[0012] The boundary contour scanning test in step (2) specifically includes:

[0013] The host computer controls the application of a minimum current I to the grating. min The grating then proceeds from I in increments of ΔI. min to I maxPower is applied sequentially, and the wavelength meter tests synchronously and transmits the output wavelength data corresponding to each current level to the host computer for output recording.

[0014] The host computer controls the grating to apply the maximum current I. max The grating then proceeds from I in increments of ΔI. min to I max Power is applied sequentially, and the wavelength meter tests synchronously and transmits the output wavelength data corresponding to each current level to the host computer for output recording.

[0015] After the host computer controls the grating, a minimum current I is applied. min The front grating is incremented by a step value ΔI from I min to I max Power is applied sequentially, and the wavelength meter tests synchronously and transmits the output wavelength data corresponding to each current level to the host computer for output recording.

[0016] After the host computer controls the grating, the maximum current I is applied. max The front grating is incremented by a step value ΔI from I min to I max Power is applied sequentially, and the wavelength meter performs synchronous tests and transmits the output wavelength data corresponding to each current level to the host computer for output recording.

[0017] The total number of test points for the boundary contour scanning test in step (2) is 4 × [(I max -I min ) / ΔI].

[0018] In step (1), the driving current adjustment range of the front grating and the rear grating is 0-50mA, and the current step value is 0.5mA.

[0019] The boundary scan data processing method in step (3) is as follows: using the front grating driving current as the horizontal axis, the rear grating driving current as the vertical axis, and the output wavelength as the vertical axis, a three-dimensional data model is constructed. The four sets of on-axis interval wavelength data collected in step (2) are plotted in the three-dimensional data model to correspond to X=I. min X=I max Y=I min Y=I max The boundary wavelength line.

[0020] The effective tuning core range in step (3) is determined by the following method: The host computer automatically analyzes the boundary wavelength lines in the three-dimensional data model through the built-in algorithm, identifies the wavelength jump range, and determines the current-wavelength range of a single tuning channel of the SGDBR semiconductor tunable laser; the midpoint of the current between the two boundaries of each tuning channel is selected, and the midpoints of the current of each channel are connected in sequence to form the tuning channel center line. The current range is extended to both sides by a preset ratio based on the center line to obtain the effective tuning core range.

[0021] The wavelength jump range is the point where the wavelength changes abruptly, serving as the boundary of the tuning channel.

[0022] The precise calibration in step (4) includes: using the center line of each tuning channel determined in step (3) as the reference scanning path, using a current step value smaller than that of the boundary contour scanning in step (2), synchronously adjusting the driving current of the front grating and rear grating regions, synchronously collecting the laser output wavelength data corresponding to each current point and storing it in association with the driving current value.

[0023] The precise calibration step (4) also includes: independently fitting the current-wavelength data collected in each tuning channel to obtain the wavelength-current correspondence of each channel; selecting verification points to verify the accuracy of the calibration results, and completing the precise calibration of the laser wavelength tuning performance.

[0024] The beneficial effects of this invention: I min X=I max

[0025] (1) This invention uses a zigzag boundary contour scanning test, and only tests the four sets of axis upper boundary intervals of the front and rear grating drive current adjustment range. The number of test points is reduced from the traditional full matrix test (I max -I min / ΔI) 2 The number is reduced to 4×(I) max -I min / ΔI) number, a reduction of more than 90%; at the same time, the fully automatic coordination of drive current regulation and wavelength meter data acquisition is realized through the host computer, eliminating the delay of manual operation, and the complete test calibration time of a single device is shortened from more than 360 minutes (about 6 hours) in the traditional method to less than 30 minutes, and the overall test efficiency is improved by more than 10 times.

[0026] (2) The present invention uses a host computer to perform precise digital control of the laser driving module, and the output accuracy of the grating driving current can reach ±0.01mA; with the high-precision wavelength detection device to collect data synchronously, the wavelength acquisition accuracy can reach ±0.001nm, and the one-to-one correspondence between current and wavelength data is strong, which effectively reduces test error and improves calibration accuracy.

[0027] (3) This invention eliminates a large number of invalid test points in non-core tuning ranges in traditional full matrix testing, and only collects wavelength data on the key axis. The data collected by the wavelength meter is transmitted to the host computer in real time. Combined with the host computer software, the heat map is automatically drawn and the tuning channel is determined, avoiding the tedious operation of manually screening data and significantly improving data processing efficiency.

[0028] (4) This invention employs a layered testing strategy: first, boundary scanning to determine the channel profile, and then fine calibration of the core region. The boundary scanning data accurately identifies wavelength jump intervals to determine the tuning channel boundary, and then fine scanning and independent data fitting are performed along the centerline of the tuning channel on the core effective region. This method significantly reduces the number of test points while ensuring that the calibration accuracy of the current-wavelength matching relationship is comparable to that of traditional full-matrix testing methods, meeting the wavelength tuning accuracy requirements of SGDBR semiconductor tunable lasers in fields such as optical communication, lidar, and spectral analysis.

[0029] (5) The entire test calibration process is fully automated. Only basic test parameters such as the grating current adjustment range and step value need to be set in the host computer software. The system can automatically complete the entire process of current regulation, wavelength acquisition, data processing, result fitting and accuracy verification without the need for complicated manual operation and intervention. This method has a low operating threshold, high stability and good consistency, and can be integrated into the existing semiconductor laser mass production test line.

[0030] (6) The test method of the present invention has strong versatility and configurability. Various test parameters can be flexibly adjusted through host computer software to adapt to SGDBR semiconductor tunable lasers of different designs and specifications. At the same time, the wavelength detection device can be flexibly configured according to the working wavelength range of the laser, and is suitable for the test and calibration of various SGDBR semiconductor tunable lasers covering the visible light to near-infrared band. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 This is a schematic diagram of the overall process for rapid wavelength testing and calibration of SGDBR semiconductor tunable lasers.

[0033] Figure 2 A schematic diagram of the hardware link connection for rapid wavelength testing and calibration of SGDBR semiconductor tunable lasers.

[0034] Figure 3 This is a schematic diagram of the test interval for the front and rear grating drive current in a loop pattern.

[0035] Figure 4 Pseudo-color plot of front and rear grating current-output wavelength and U-shaped wavelength line (actual measurement data).

[0036] Figure 5Schematic diagram for determining the tuning channel range and selecting the midpoint of an SGDBR semiconductor tunable laser. Detailed Implementation

[0037] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0038] The testing system used in this invention mainly includes the following components:

[0039] Host computer: an industrial control computer, equipped with self-developed test calibration software, responsible for the control, data processing and result storage of the entire test process;

[0040] Laser driver module: multi-channel high-precision current source, capable of independently outputting drive current for the front grating, rear grating, gain region and phase region, with a current output range of 0-100mA and an accuracy of ±0.01mA;

[0041] Wavelength detection device: High-precision wavelength meter or spectrometer, capable of measuring the output wavelength of the laser in real time, with a wavelength measurement range covering the working wavelength band of the laser under test, and an accuracy of ±0.001nm;

[0042] Optical connection components: including single-mode optical fibers, fiber couplers, etc., are used to couple the output light of the laser to the wavelength detection device.

[0043] The host computer connects to the laser driver module and wavelength detection device via industrial communication interfaces such as USB, RS232, RS485, GPIB or Ethernet.

[0044] Step (1): Establish a test control system

[0045] Before the test begins, it is necessary to set the driving current adjustment range of the front grating and rear grating regions and other basic test parameters according to the specifications of the SGDBR semiconductor tunable laser under test.

[0046] Drive current adjustment range setting: The drive current adjustment ranges for the front and rear gratings can be set independently, typically expressed as I. min -I max .in:

[0047] I minThis represents the minimum value of the grating drive current, typically ranging from 0mA to 2mA. For most forward-injection SGDBR lasers, the effective tuning range begins at 0mA; however, for some lasers exhibiting severe mode instability at low currents, IA can be increased. min The current should be appropriately increased to 1mA-2mA to ensure the reliability of the test data.

[0048] I max This is the maximum value of the grating drive current, typically ranging from 30mA to 80mA. This value is determined by the laser's chip design, material system, and thermal management capabilities, and is usually taken as the maximum operating current recommended by the laser manufacturer.

[0049] For the vast majority of commercial C-band SGDBR lasers, the standard drive current adjustment range is 0-50mA.

[0050] Current step value setting: The current step value ΔI refers to the step size by which the driving current increases each time during the scanning test, typically ranging from 0.1mA to 2mA. The selection of the step value requires a balance between test speed and accuracy.

[0051] For rapid screening tests, a larger step value (1mA-2mA) can be used to further shorten the testing time;

[0052] For standard mass production testing, a step value of 0.5mA is usually used, which is the current industry standard.

[0053] For high-precision laboratory testing, a smaller step value (0.1mA-0.2mA) can be used to obtain higher testing accuracy.

[0054] Other basic test parameters: In addition to the parameters mentioned above, it is also necessary to set parameters such as gain region current, phase region current, test waiting time, and number of wavelength acquisitions. The gain region current is usually set slightly higher than the laser's threshold current to ensure normal laser operation; the phase region current is usually set to 0mA during the initial test and can be optimized during subsequent calibration; the number of wavelength acquisitions refers to the number of times wavelength data is acquired at each current point, and the average of 3-5 acquisitions is usually taken to improve accuracy.

[0055] After the parameters are set, the host computer automatically establishes a communication link with the laser driver module and the wavelength detection device, and performs a system self-test to confirm that each device is working properly.

[0056] Step (2): Boundary contour scanning test

[0057] Each tuning channel of an SGDBR laser spans the entire current plane, so by scanning the four boundaries of the current plane, the boundary information of all tuning channels can be fully captured.

[0058] The specific test process is as follows:

[0059] Fix the front grating at the minimum value and scan the rear grating: The host computer controls the laser driver module to set the drive current of the front grating to I min and keep it unchanged, then set the drive current of the rear grating from I min and increase it step by step with a step value of ΔI to I max . At each current point, after waiting for the preset stabilization time, the wavelength detection device collects the output wavelength data of the laser and transmits the data to the host computer for storage.

[0060] Fix the front grating at the maximum value and scan the rear grating: Set the drive current of the front grating to I max and keep it unchanged, repeat the above scanning process, and collect the wavelength data corresponding to the full-range scan of the rear grating.

[0061] Fix the rear grating at the minimum value and scan the front grating: Set the drive current of the rear grating to I min and keep it unchanged, then set the drive current of the front grating from I min and increase it step by step with a step value of ΔI to I max , and synchronously collect the wavelength data.

[0062] Fix the rear grating at the maximum value and scan the front grating: Set the drive current of the rear grating to I max and keep it unchanged, repeat the above scanning process, and collect the wavelength data corresponding to the full-range scan of the front grating.

[0063] The above four scanning steps form a complete "square" shape, covering the four boundaries of the current plane, so it is also called the "square scanning test".

[0064] Calculation of the number of test points: The total number of test points for the boundary contour scanning test is: N = 4 × [(I max - I min ) / ΔI]

[0065] For example, when I min = 0 mA, I max = 50 mA, and ΔI = 0.5 mA, the total number of test points is 4 × (50 / 0.5) = 400, while the traditional full matrix test requires 100 × 100 = 10,000 test points, and the number of test points is reduced by 96%. This is the fundamental reason why the present invention can greatly shorten the test time.

[0066] Step (3): Tuning channel range identification

[0067] After the boundary contour scanning test is completed, the host computer processes the collected boundary data to determine the range of all tuning channels of the laser.

[0068] 3D Data Model Construction: The host computer software automatically constructs a 3D data model with the front grating drive current as the X-axis, the rear grating drive current as the Y-axis, and the output wavelength as the Z-axis. This model can be in the form of a 3D surface plot, a 3D scatter plot, or a 3D heat map, which can intuitively show how the wavelength changes with the two grating drive currents.

[0069] Boundary wavelength line drawing: The four sets of boundary data collected in step (2) are drawn in the three-dimensional data model to form four boundary wavelength lines, corresponding to X=I respectively. min X=I max Y=I min and Y=I max .

[0070] Wavelength jump interval identification: A key characteristic of SGDBR lasers is that wavelength jumps occur at the boundaries of the tuning channel, meaning there is a sudden change in wavelength between two adjacent test points. The host computer automatically analyzes four boundary wavelength lines using a built-in algorithm to identify the points of wavelength abrupt change as the boundaries of the tuning channel.

[0071] The criteria for determining wavelength abrupt changes can be set according to actual needs, typically when the wavelength change between two adjacent test points exceeds a preset threshold (usually 0.1nm-1nm, with a typical value of 0.5nm). Commonly used recognition algorithms include differential methods, threshold methods, and edge detection methods.

[0072] Effective tuning core interval determination: After identifying the boundaries of all tuning channels, the host computer further determines the effective tuning core interval for each tuning channel. The specific method is as follows:

[0073] Calculate the midpoint of the current between the two boundaries of each tuning channel;

[0074] Connect the midpoints of the current in all channels sequentially to form the center line of the tuning channel;

[0075] Using the center line of the tuning channel as a reference, the effective tuning core range of each channel is obtained by expanding to both sides.

[0076] The area near the center line of the tuning channel is where the wavelength linearity is best and the mode is most stable within each channel. Using this as a reference for subsequent fine scanning can achieve the highest calibration accuracy.

[0077] Step (4): Precise calibration

[0078] After determining the effective core range of each tuning channel, the host computer performs fine scanning tests and data fitting on each core range to obtain an accurate current-wavelength correspondence.

[0079] Fine scanning along the centerline: For each tuning channel, the centerline of the tuning channel determined in step (3) is used as the reference scanning path. A current step value smaller than that of the boundary contour scan (usually 1 / 2 to 1 / 10 of the boundary scan step value) is used to synchronously adjust the driving current of the front grating and the rear grating. At each current point, the wavelength detection device synchronously collects the output wavelength data of the laser and stores the current value and wavelength value in a one-to-one correspondence.

[0080] Synchronously adjusting the drive currents of the two gratings is crucial for achieving continuous wavelength tuning in SGDBR lasers. During scanning, the current changes of the front and rear gratings are determined based on the slope of the tuning channel centerline to ensure the laser always operates on the centerline of the tuning channel.

[0081] Independent channel fitting: After fine scanning, the host computer independently fits the current-wavelength data acquired in each tuning channel. Independent channel fitting avoids the accuracy degradation caused by cross-channel fitting and improves the calibration accuracy of each channel.

[0082] Commonly used fitting methods include linear fitting, quadratic polynomial fitting, and cubic polynomial fitting. For most SGDBR lasers, linear fitting is sufficient to meet the accuracy requirements.

[0083] Accuracy Verification: To ensure the reliability of the calibration results, the host computer randomly selects 3-5 verification current points in each tuning channel, controls the laser to output the corresponding wavelength, and compares the actual measured wavelength value with the fitted predicted value to calculate the calibration error. If the error meets the preset requirements, the calibration is complete; if the error does not meet the requirements, the fine scanning step value is reduced, and the test and fitting are repeated.

[0084] Calibration Result Output: After calibration, the host computer generates a standardized calibration file containing the boundary currents, center currents, fitting coefficients, and verification results for all channels. This calibration file can be stored on the host computer or written to the non-volatile memory of the laser driver module via a communication link. In practical applications, the laser driver module automatically queries the calibration file and calculates the corresponding front and rear grating drive currents based on the input target wavelength, achieving precise wavelength tuning.

[0085] Example 1

[0086] A rapid testing and calibration method for the wavelength of an SGDBR semiconductor tunable laser, the overall process is as follows: Figure 1As shown, the specific operating steps for adjusting the front and rear grating drive current of the SGDBR semiconductor tunable laser within the range of 0-50mA with a current step value of 0.5mA are as follows:

[0087] (1) Test parameter setting and test link setup: The drive current adjustment range of the front and rear gratings is set to 0-50mA with a current step value of 0.5mA using the host computer test software. The wavelength acquisition frequency of the wavelength meter is set to 10Hz. The automatic acquisition and saving path for test data is set. The test link is then set up, such as... Figure 2 As shown, the host computer and the laser drive module are electrically connected via an RS485 interface. The host computer outputs a current control signal to the drive module to achieve precise control of the drive current of the front and rear gratings. The optical output end of the laser is connected to the optical input end of the wavelength meter via a single-mode optical fiber. The wavelength meter is connected to the host computer via Ethernet communication to collect the output wavelength data of the laser in real time and transmit it to the host computer for output and storage. The laser test system is then started.

[0088] (2) Square-shaped scanning test and wavelength data acquisition:

[0089] The front grating current is controlled to be 0mA, and the rear grating current is increased from 0mA to 50mA in 0.5mA steps, with a total of 100 test points. The output wavelength corresponding to each current level is automatically tested and recorded.

[0090] The front grating current is controlled at 50mA, and the rear grating current is increased from 0mA to 50mA in 0.5mA steps, with a total of 100 test points. The output wavelength corresponding to each current level is automatically tested and recorded.

[0091] The rear grating current is controlled to be 0mA, and the front grating current is increased from 0mA to 50mA in 0.5mA steps, with a total of 100 test points. The output wavelength corresponding to each current level is automatically tested and recorded.

[0092] The rear grating current is controlled to be 50mA, and the front grating current is increased from 0mA to 50mA in 0.5mA steps, with a total of 100 test points. The output wavelength corresponding to each current level is automatically tested and recorded.

[0093] This zigzag scanning test collected current-wavelength data from 400 test points. The entire process was completed automatically by the software and took approximately 15 minutes.

[0094] (3) Construction of 3D Heatmap and Drawing of U-Shaped Wavelength Lines: The host computer software automatically constructs a 3D heatmap with the front grating current as the X-axis, the rear grating current as the Y-axis, and the output wavelength as the Z-axis, such as... Figure 3As shown; the 400 collected data points were mapped onto a heatmap, and a U-shaped wavelength line was drawn with X=0, X=50, Y=0, Y=50, visually presenting the correspondence between on-axis current and wavelength, as shown. Figure 4 As shown;

[0095] (4) Determining the tuning channel range: The host computer software automatically identifies the wavelength jump intervals in the U-shaped wavelength line (the wavelength abrupt change is the boundary of the tuning channel), thereby determining the current-wavelength range of a single tuning channel of the laser; the current interval of each tuning channel is calculated, and the midpoint of the interval is selected (e.g., 5mA is selected as the midpoint for the 0-10mA interval). The midpoints of all tuning channels are connected end to end to form the complete wavelength tuning channel outline of the laser, and the core tuning current interval is determined, such as... Figure 5 As shown;

[0096] (5) Linear power-on test and precise calibration: Within the core tuning current range determined in step 4, control the front and rear gratings to perform linear power-on tests in 0.5mA steps, and collect the current-wavelength matching data within this range; perform linear fitting of the data through software to obtain the precise current-wavelength correspondence of the laser, and automatically generate a test calibration report, including key parameters such as tuning channel range, current-wavelength fitting formula, and wavelength tuning accuracy, to complete the entire test calibration process. This step takes about 8 minutes.

[0097] Test calibration complete: Save the test calibration report and close the laser test system. If you need to test the next device, repeat steps 1-5. There is no need to readjust the test system parameters.

[0098] Using the above method, the complete test and calibration time of a single SGDBR semiconductor tunable laser wavelength can be controlled within 30 minutes. The calibration accuracy is consistent with the traditional full-matrix point-by-point test, and the wavelength tuning accuracy deviation is ≤ ±0.02nm. This fully meets the high-efficiency and accurate test and calibration requirements of the mass production stage and greatly improves production efficiency.

[0099] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A rapid testing and calibration method for the wavelength of an SGDBR semiconductor tunable laser, wherein the SGDBR semiconductor tunable laser comprises a front grating and a rear grating, characterized in that, Includes the following steps: (1) Set the driving current adjustment range and basic test parameters for the front and rear grating regions; construct a communication link between the host computer and the laser driving module and wavelength detection device so that the host computer can independently adjust the driving current of each grating region and receive the laser output wavelength data collected by the wavelength detection device in real time. (2) Boundary contour scanning test: The driving current of the front grating area is fixed at two boundary values ​​within its adjustment range, and the driving current of the rear grating area is subjected to full-range scanning test within its adjustment range, and the corresponding output wavelength data is collected synchronously. The driving current of the rear grating region is fixed at two boundary values ​​of its adjustment range, and the driving current of the front grating region is subjected to full-range scanning test within its adjustment range, while the corresponding output wavelength data is collected synchronously. (3) Tuning channel range identification: The boundary scan data collected in step (2) is processed to identify the wavelength change interval as the boundary of the tuning channel; based on the identified channel boundary, the current-wavelength mapping range and effective tuning core interval of each tuning channel are determined. (4) Precise calibration: Within the effective tuning core range of each tuning channel determined in step (3), the driving current of the front grating and rear grating regions is finely scanned and tested, and the corresponding current-wavelength matching data is collected; the current-wavelength correspondence is obtained through data fitting, and the wavelength tuning performance calibration of the SGDBR semiconductor tunable laser is completed.

2. The rapid testing and calibration method for the wavelength of an SGDBR semiconductor tunable laser according to claim 1, characterized in that, In step (1), the driving current adjustment range of the front grating and the rear grating is independently I. min -I max The current step value is ΔI; where I min for 0mA-2mA, I max The range is 30mA-80mA, and ΔI is 0.1-2mA.

3. The rapid testing and calibration method for the wavelength of an SGDBR semiconductor tunable laser according to claim 2, characterized in that, The boundary contour scanning test described in step (2) specifically includes: The host computer controls the application of a minimum current I to the grating. min The grating then proceeds from I in increments of ΔI. min to I max Power is applied sequentially, and the wavelength meter tests synchronously and transmits the output wavelength data corresponding to each current level to the host computer for output recording. The host computer controls the grating to apply the maximum current I. max The grating then proceeds from I in increments of ΔI. min to I max Power is applied sequentially, and the wavelength meter tests synchronously and transmits the output wavelength data corresponding to each current level to the host computer for output recording. After the host computer controls the grating, a minimum current I is applied. min The front grating is incremented by a step value ΔI from I min to I max Power is applied sequentially, and the wavelength meter tests synchronously and transmits the output wavelength data corresponding to each current level to the host computer for output recording. After the host computer controls the grating, the maximum current I is applied. max The front grating is incremented by a step value ΔI from I min to I max Power is applied sequentially, and the wavelength meter performs synchronous tests and transmits the output wavelength data corresponding to each current level to the host computer for output recording.

4. The rapid testing and calibration method for the wavelength of an SGDBR semiconductor tunable laser according to claim 2 or 3, characterized in that, The total number of test points in the boundary contour scanning test in step (2) is 4 × [(I max -I min ) / ΔI].

5. The rapid testing and calibration method for the wavelength of an SGDBR semiconductor tunable laser according to claim 2, characterized in that, In step (1), the driving current adjustment range of the front grating and the rear grating is 0-50mA, and the current step value is 0.5mA.

6. The rapid testing and calibration method for the wavelength of an SGDBR semiconductor tunable laser according to claim 1, characterized in that, The boundary scan data processing method described in step (3) is as follows: using the front grating driving current as the horizontal axis, the rear grating driving current as the vertical axis, and the output wavelength as the vertical axis, a three-dimensional data model is constructed. The four sets of on-axis interval wavelength data collected in step (2) are plotted in the three-dimensional data model to correspond to X=I. min X=I max Y=I min Y=I max The boundary wavelength line.

7. The rapid testing and calibration method for the wavelength of an SGDBR semiconductor tunable laser according to claim 6, characterized in that, The effective tuning core range mentioned in step (3) is determined by the following method: The host computer automatically analyzes the boundary wavelength lines in the three-dimensional data model through the built-in algorithm, identifies the wavelength jump range, and determines the current-wavelength range of a single tuning channel of the SGDBR semiconductor tunable laser; selects the midpoint of the current between the two boundaries of each tuning channel, connects the midpoints of the current of each channel in sequence to form the center line of the tuning channel, and expands the current range to both sides by a preset ratio based on the center line to obtain the effective tuning core range.

8. The rapid testing and calibration method for the wavelength of an SGDBR semiconductor tunable laser according to claim 7, characterized in that, The wavelength jump range is the point where the wavelength changes abruptly, serving as the boundary of the tuning channel.

9. The rapid testing and calibration method for the wavelength of an SGDBR semiconductor tunable laser according to claim 7, characterized in that, The precise calibration in step (4) includes: using the center line of each tuning channel determined in step (3) as the reference scanning path, using a current step value smaller than that of the boundary contour scanning in step (2), synchronously adjusting the driving current of the front grating and rear grating regions, synchronously collecting the laser output wavelength data corresponding to each current point and storing it in association with the driving current value.

10. The rapid testing and calibration method for the wavelength of an SGDBR semiconductor tunable laser according to claim 9, characterized in that, The precise calibration in step (4) also includes: independently fitting the current-wavelength data collected in each tuning channel to obtain the wavelength-current correspondence of each channel; selecting verification points to verify the accuracy of the calibration results, and completing the precise calibration of the laser wavelength tuning performance.

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