Laser power correction method and device for suppressing relaxation oscillation and laser

Abstract

The application provides a laser power correction method and device for inhibiting relaxation oscillation and a laser, and the method comprises the following steps: setting the laser to a first duty ratio and a first frequency, adjusting a current to make an average power a preset power, and recording a current value; adjusting the frequency to make the average power the preset power, recording all frequency values to obtain a frequency interval; changing the duty ratio to obtain the frequency interval under each duty ratio; setting the laser to a second duty ratio and a representative frequency, adjusting the current to make the average power minimum and maximum average power, recording minimum and maximum currents, and determining a current-average power relationship; and changing the duty ratio to obtain the current-average power relationship under each duty ratio and different frequency intervals. The application is suitable for a pulse laser control mode for inhibiting relaxation oscillation and increasing small step signals, and the current-average power relationship is determined by actually measuring a power output value, so that accurate correction of the laser is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of laser power correction, and in particular to a laser power correction method and device for suppressing relaxation oscillation, and a laser. Background Art

[0002] In pulsed lasers, the calculation formula for laser power is as follows: Among them, P a is the average power, P p is the peak power, t is the peak pulse duration, and f is the pulse output frequency. If you want to change the average laser power, you can modify P p At least one of the three parameters , t, and f.

[0003] However, after leaving the factory, lasers naturally age and are affected by time and the environment. When the laser is actually used, its current-peak power curve may deviate from the factory specifications. Therefore, power calibration is necessary to determine the actual current-peak power relationship. Existing power calibration methods recalibrate the drive current when the average power output of the laser is deemed inaccurate.

[0004] Taking fiber lasers as an example, relaxation oscillation occurs when the gain fiber generates laser light. If it is not suppressed, there is a high probability of damage to the optical components in the laser light path. Therefore, it is necessary to suppress the peak power of the relaxation oscillation light within an acceptable range. For example, the relaxation oscillation can be suppressed by adding a small step signal to the driving current square wave to suppress the relaxation oscillation.

[0005] The existing correction method performs correction calculations based on a square wave. After adding a small step signal to suppress relaxation oscillation, the laser energy of the small step is increased. According to the existing correction method, the output average laser power will be inaccurate. Summary of the Invention

[0006] To solve the above problems, the present invention provides a laser power correction method for suppressing relaxation oscillation, comprising: step one, setting the duty cycle of the laser to a first duty cycle and the frequency to a first frequency, adjusting the current so that the average power output by the laser is a preset power, and recording the current value; the waveform of the current includes a first order and a second order, the amplitude of the first order is less than the amplitude of the second order, and the amplitude of the laser relaxation oscillation waveform induced by the current signal of the first order is less than a safety threshold; step two, using the current value and the first duty cycle, adjusting the frequency so that the average power output by the laser is the preset power, recording all frequency values ​​to obtain a frequency interval; changing the duty cycle, repeating steps one and two, and obtaining the laser power at each frequency intervals under a duty cycle; each of the frequency intervals corresponds to a representative frequency; step three, setting the duty cycle of the laser to a second duty cycle and the frequency to the representative frequency, adjusting the current so that the average power output by the laser is the minimum average power and the maximum average power, and recording the corresponding current as the minimum current and the maximum current; and determining the current-average power relationship based on the minimum current, the maximum current, the peak power corresponding to the maximum current, the peak power corresponding to the minimum current, the second duty cycle, the peak power corresponding to the first order, the duration of the first order, and the representative frequency; changing the duty cycle, repeating step three, and obtaining the current-average power relationship of the laser at each duty cycle and in different frequency intervals.

[0007] The laser power calibration method for suppressing relaxation oscillations provided in an embodiment of the present invention is applicable to a pulsed laser control method that adds a small step signal for suppressing relaxation oscillations. It not only refers to the current power curve of the laser manufacturer, but also determines the actual current-average power relationship by actually measuring the power output value of the laser, thereby achieving accurate calibration of the laser.

[0008] Optionally, the current-average power relationship is as follows:

[0009] I out =[(P out -P p_It0 *t0*fP Ith *D) / (P pmax *DP Ith *D)](I max -I th )+I th

[0010] Among them, I out is the current, P out is the average laser output power, P p_It0 is the peak power of the first order, t0 is the duration of the first order, f is the representative frequency, PIth *D is the minimum average power, P pmax *D is the maximum average power, P pmax is the peak power corresponding to the maximum current, P Ith is the peak power corresponding to the minimum current, D is the duty cycle, I max is the maximum current, I th is the minimum current.

[0011] The embodiment of the present invention provides a calculation formula for the current-average power relationship, which can achieve accurate calibration of the laser.

[0012] Optionally, the preset power is the minimum average power or the maximum average power of the laser; or, the preset power is the power within the tolerance of the minimum average power or the maximum average power of the laser.

[0013] In the embodiment of the present invention, the relationship between current and average power is determined based on the minimum average power, the maximum average power and their corresponding minimum current and maximum current, thereby achieving accurate calibration of the laser.

[0014] Optionally, the median of the frequency interval is set as the corresponding representative frequency.

[0015] In the embodiment of the present invention, the frequencies involved in the laser are segmented, thereby simplifying the workload of power calibration.

[0016] Optionally, the method further includes: determining the single pulse energy of the first order.

[0017] The correction method in the embodiment of the present invention further includes calculating the single pulse energy of the small step signal that suppresses relaxation oscillation, thereby determining the pulse energy of the small step signal and its impact on the normal output of the laser.

[0018] Optionally, the calculation formula for the single pulse energy is as follows:

[0019] E=P a_It0 / f

[0020] Where E is the single pulse energy, P a_It0 is the average power of the first order, and f is the frequency.

[0021] Optionally, the calculation formula for the single pulse energy is as follows:

[0022] E=P a_It0* t0

[0023] Where E is the single pulse energy, P a_It0 is the average power of the first order, and t0 is the duration of the first order.

[0024] The embodiment of the present invention provides a specific calculation method for the pulse energy of a small step signal, thereby determining the pulse energy of the small step signal and its influence on the normal output of the laser.

[0025] An embodiment of the present invention provides a laser power correction device for suppressing relaxation oscillation, comprising: a frequency segmentation module, configured to perform the following steps: step one, setting the duty cycle of the laser to a first duty cycle and the frequency to a first frequency, adjusting the current so that the average power output by the laser is a preset power, and recording the current value; the waveform of the current comprises a first order and a second order, the amplitude of the first order is less than the amplitude of the second order, and the amplitude of the laser relaxation oscillation waveform induced by the current signal of the first order is less than a safety threshold; step two, using the current value and the first duty cycle, adjusting the frequency so that the average power output by the laser is the preset power, recording all frequency values ​​to obtain a frequency interval; changing the duty cycle, repeating steps one and two, and obtaining the laser power at each duty cycle. frequency intervals under the duty cycle; each of the frequency intervals corresponds to a representative frequency; a power correction module is used to perform the following steps: step three, setting the duty cycle of the laser to a second duty cycle and the frequency to the representative frequency, adjusting the current so that the average power output by the laser is the minimum average power and the maximum average power, and recording the corresponding current as the minimum current and the maximum current; and determining the current-average power relationship according to the minimum current, the maximum current, the peak power corresponding to the maximum current, the peak power corresponding to the minimum current, the second duty cycle, the peak power corresponding to the first order, the duration of the first order, and the representative frequency; changing the duty cycle and repeating step three to obtain the current-average power relationship of the laser at each duty cycle and in different frequency intervals.

[0026] Optionally, the current-average power relationship is as follows:

[0027] I out =[(P out -P p_It0 *t0*fP Ith *D) / (P pmax *DP Ith *D)](I max -I th )+I th

[0028] Among them, I out is the current, P out is the average laser output power, P p_It0 is the peak power of the first order, t0 is the duration of the first order, f is the representative frequency, P Ith *D is the minimum average power, P pmax*D is the maximum average power, P pmax is the peak power corresponding to the maximum current, P Ith is the peak power corresponding to the minimum current, D is the duty cycle, I max is the maximum current, I th is the minimum current.

[0029] An embodiment of the present invention provides a laser, comprising a computer-readable storage medium storing a computer program and a processor. When the computer program is read and executed by the processor, the laser power correction method for suppressing relaxation oscillation is implemented.

[0030] The laser power calibration device and laser for suppressing relaxation oscillation provided in the embodiments of the present invention can achieve the same technical effect as the above-mentioned laser power calibration method for suppressing relaxation oscillation. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are merely embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0032] Figure 1 The driving current and laser output power curve of the laser diode provided in the embodiment of the present invention;

[0033] Figure 2 A schematic flow chart of a laser power calibration method for suppressing relaxation oscillation provided by an embodiment of the present invention;

[0034] Figure 3 A schematic structural diagram of a laser power correction device for suppressing relaxation oscillation provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0035] In order to make the above-mentioned objects, features and advantages of the present invention more clearly understood, the following detailed description of the specific embodiments of the present invention is given in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0036] The parameters involved in the embodiments of the present invention are as follows: average power (Pa), peak power (Pp), pulse energy (Ep), pulse output frequency (f), duty ratio (D), and peak pulse duration t.

[0037] Patent 202410703660X describes a laser current control method for suppressing laser relaxation oscillations. A small step current waveform is designed to suppress relaxation oscillations. The current control algorithm formula for suppressing relaxation oscillations is as follows:

[0038] P out =P p_It0* (t 0* f)+[(I out -I th ) / (I max -I th )]*(P pmax *D)

[0039] Among them, P out is the average laser output power, P p_It0 is the peak power corresponding to the first order, t0 is the duration of the first order, f is the representative frequency, I out is the driving current, I max is the maximum drive current, I th is the threshold current, P pmax is the laser peak power corresponding to the maximum driving current, and D is the duty cycle corresponding to the second order.

[0040] A premise of the above derivation formula is as described in the patent description, I th The value selected is when the laser diode (LD) just emits light, and the average power at this time can be basically ignored. In actual laser medical device products, each time the threshold current I is selected when the laser LD just emits light th For example, using a laser power meter to measure the threshold current I th The average power of the laser output when driving the LD is very weak, so it is difficult to measure it, making it difficult to judge the I th Take the appropriate amount.

[0041] In order to solve the difficulties described above, the above control algorithm is expanded and the minimum output average power of a product is selected as I th The corresponding average power P aIth , at this time I th The corresponding peak power is P th .

[0042] Figure 1 is the driving current and laser output power curve of the laser diode. Figure 1 The lower middle side is the current-laser peak power curve, and the upper side is the current-voltage curve. Figure 1The current at point A is I th , the corresponding peak power is P Ith , the current at point E is I out , the corresponding peak power is P pset , the current at point B is I max , the corresponding peak power is P pmax .

[0043] The embodiment of the present invention is based on Figure 1 Further expansion of the algorithm in the existing patent 202410703660X can obtain formula ①:

[0044] I out = [ (P out -P p_It0 *t0 * f- P Ith *D ) / (P pmax *D - P Ith *D) ](I max -I th )+ I th ①

[0045] Among them, I out is the current, P out is the average laser output power, P p_It0 is the peak power of the first order, t0 is the duration of the first order, f is the representative frequency, P Ith *D is the minimum average power, P pmax *D is the maximum average power, P pmax is the peak power corresponding to the maximum current, P Ith is the peak power corresponding to the minimum current, D is the duty cycle, I max is the maximum current, I th is the minimum current.

[0046] based on Figure 1 As shown, formula ① is derived as follows:

[0047]

[0048] Therefore, when calibrating the power, we only need to find the I corresponding to each frequency segment. max and I th , and P pmax , you can set the P pset Calculate the required current; peak power P Ith The average power P at this time aIth The formula relationship is as follows:

[0049] P Ith =P aIth / D Formula 2

[0050] D is the duty cycle, P aIth is the average power, P Ith It is now I th The corresponding peak power at duty cycle D.

[0051] According to the current-peak power curve derived from the above formula, if I th =1.5A, the corresponding P Ith Equal to 0, at this time the P of the above formula 1 Ith The effect of is negligible, which is equivalent to:

[0052] I out =(P pset )(I max -I th ) / (P pmax )+I th

[0053] According to actual needs, you can choose the appropriate peak power (I th ,P Ith ) as a starting point.

[0054] The average power P of the laser output out , equal to the average power P of the small step t0 Add the average power P output by the current curve set , so we have:

[0055] P out =P t0 +P Iout Formula 3

[0056] And because the average power P that needs to be output Iout Equal to I out The corresponding peak power P pset Multiplying by the duty cycle D, that is, adjusting the current corresponding to the effective current t1 period, a laser peak power P can be obtained. pset , the peak power multiplied by the duty cycle equals the average power P at this time Iout ,then:

[0057] P Iout = P pset * D Formula 4

[0058] Furthermore, given formulas 1, 2, and 4,

[0059] ∴ I out = [(P Iout -P aIth ) / (P pmax *D - PaIth ) ] * (I max -I th )+ I th Formula 5

[0060] According to similar triangles, I th You can take the value when the laser just starts to emit light and is ready to emit laser light (the laser peak power at this time is close to 0W). This value is fixed according to the laser pump source model. You can also set this I according to the laser flat power range of the laser. th Take a bigger one, get the right one (I th ,P Ith ). For example, if the average laser power range is 0.5W to 20W, then P aIth =0.5W can be achieved through P Ith =P aIth / D calculates the peak power P Ith， However, according to Formula 4 derived from Formula 1, Formula 4 at this time becomes:

[0061] I out =[(P Iout –0.5) / (P pmax *D–0.5)]*(I max -I th )+I th

[0062] And because the maximum output current I max It must correspond to the maximum laser peak power P pmax , so P pmax and I max is a fixed known value. And because the duty cycle of the output current waveform is known, the average power P required to be output is Iout You can calculate how much current I the MCU needs to output out .

[0063] According to formula 3, there is a small step difference between the laser power output by the laser device terminal and the average laser power output by the current regulation. t0， Because the current value and duration t0 of the small step that suppresses the damage of relaxation oscillation are fixed through circuit debugging (the principle is to debug the output current size and t 0， Observe whether the waveform of laser waveform relaxation oscillation does not exceed the tolerance value of optical components in the optical path), so P t0 is a constant. So as long as we calculate P t0 , you can get the regulated output current I out and the average power P output by the laser equipment terminal out The relationship is as follows:

[0064] I out = ( ((P out -P t0 ) - P aIth ) / (P pmax *D - P aIth ) ) (I max -I th )+ I th Formula 6

[0065] The calculation method of the average power corresponding to the small step "t0" time is as follows.

[0066] I t0 The corresponding average power P in continuous mode t0_cw for:

[0067] P t0_cw =P p_It0

[0068] Since the width of the small step is t0, it can be considered that t0 is also a pulse waveform output at a frequency f under a certain duty cycle, and its duty cycle is:

[0069] D t0 =t0 / T=t0*f

[0070] Because the average power of the laser output in PWM mode is equal to the peak power multiplied by the duty cycle, the average power of the small step is:

[0071] P t0 =P p_It0* D t0 =P p_It0* (t0*f)

[0072] Because P p_It0 According to I t0 The query shows that t0 is a fixed value, which can be known from debugging. t0 It is also a fixed value.

[0073] So Formula 6 can be transformed into the following form:

[0074] I out =[(P out -P p_It0* t0*fP Ith *D) / (P pmax *DP Ith *D)]*(I max -I th )+I th。

[0075] Based on this formula, an embodiment of the present invention designs a power calibration method that can be better applied to laser medical products.

[0076] Figure 2 A schematic flow chart of a laser power calibration method for suppressing relaxation oscillation provided by an embodiment of the present invention is shown. The method includes a frequency segmentation process S21 and a power calibration process S22.

[0077] The above frequency segmentation process can segment the frequencies involved in the laser and simplify the power calibration workload. It specifically includes the following steps:

[0078] Step 1: Set the duty cycle of the laser to a first duty cycle and the frequency to a first frequency, adjust the current so that the average power output by the laser is a preset power, and record the current value.

[0079] As described above, the current waveform includes a first order and a second order, with the amplitude of the first order being smaller than the amplitude of the second order. The amplitude of the laser relaxation oscillation waveform induced by the first order current signal is smaller than a safety threshold. This safety threshold is affected by the parameters of the components in the laser drive circuit, and relaxation oscillations with amplitudes below this safety threshold will not damage components in the optical path.

[0080] Since the higher the driving current, the higher the peak power generated by the laser diode, the higher the relaxation oscillation waveform caused in the early stage of laser balance establishment. When it is higher than a certain value, the optical device may be burned. Therefore, this embodiment first uses a smaller first-order current to allow the laser balance of the laser to be established first, and then outputs a large current corresponding to the effective PWM (PulseWidth Modulation) signal. In this way, when the large current is output to the laser diode, because the laser balance has been basically established, the subsequent large current driving the laser diode will not cause a large relaxation oscillation waveform. The amplitude of the relaxation oscillation waveform caused by the small step current in the front is relatively small and is within the acceptance range of the optical devices in the optical path, thereby successfully suppressing the damage of the relaxation oscillation to the optical devices in the optical path.

[0081] Optionally, the preset power may be the minimum average power or the maximum average power of the laser; or the preset power may be a power within a tolerance of the minimum average power or the maximum average power of the laser. For example, the tolerance is 20%.

[0082] In this embodiment, the operation is first fixed at a certain duty cycle and frequency, and the average power output is detected while adjusting the current to obtain the current corresponding to the preset power under this condition.

[0083] Current regulations on laser medical devices require that the output power of the laser terminal must be within ±20% of the power stated in the product technical requirements. For example, the power range of the product is 0.5W to 20W, and the frequency adjustment range is 1Hz to 250Hz. As described in the previous patent, I th There is I with the driving frequency th =Af+B, but according to the tolerance range required by national testing, the output frequency of the laser can be set to f, and then the duty cycle D=5%, and the output current can be adjusted so that the average power obtained at the power meter end is within the range of 0.5W±20%. The current at this time is recorded as I th .

[0084] Step 2: Using the current current value and the first duty cycle, adjust the frequency so that the average power output by the laser is the preset power, and record all frequency values ​​to obtain the frequency range.

[0085] In this embodiment, the operation is fixed at a certain duty cycle and current, and the average output power is detected while adjusting the frequency to obtain all frequency values ​​that can output the above-mentioned preset frequency. The above-mentioned frequency values ​​constitute a frequency range.

[0086] At this time, the fixed output I th and D = 5%, start to modify f, and you can count certain continuous frequency ranges (such as 0Hz ~ 150Hz, 151Hz ~ 250Hz), the same I th The effect of 0.5W±20% can be achieved. Therefore, these frequency ranges are placed within the frequency range of the above-mentioned duty cycle of 5%. For example, the pulse width gear with a duty cycle of 5% is set to two frequency segments, namely 0Hz~150Hz and 151Hz~250Hz.

[0087] By changing the duty cycle and repeating steps 1 and 2, the frequency range of the laser at each duty cycle is obtained. Each frequency range corresponds to a representative frequency.

[0088] By repeating steps 1 and 2, the frequency segmentation of the laser at all duty cycles can be obtained. There is a logic here, since I th Under a fixed duty cycle D, within a certain frequency range, the average output power is within 0.5W±20%, so the middle frequency of this frequency range is taken and marked as f re , according to I th =Af+B, it can be seen that this f re It can represent all frequencies in the frequency interval it is in to participate in the calculation of the current output. For example, the median of the above frequency interval can be set as the corresponding representative frequency.

[0089] Based on the division of the above frequency intervals, even if there are many frequencies, power correction can be performed quickly within the tolerance.

[0090] The power correction process can be formulated by selecting the maximum and minimum points of the "current-power curve". Specifically, it includes the following steps:

[0091] Step 3: Set the laser's duty cycle to the second duty cycle and the frequency to the representative frequency. Adjust the current so that the average power output by the laser is at the minimum average power and the maximum average power, and record the corresponding currents as the minimum current and the maximum current. Furthermore, determine the current-average power relationship based on the minimum current, the maximum current, the peak power corresponding to the maximum current, the peak power corresponding to the minimum current, the second duty cycle, the peak power corresponding to the first step, the duration of the first step, and the representative frequency.

[0092] Optionally, in this embodiment, the current-average power relationship is as follows:

[0093] I out =[(P out -P p_It0 *t0*fP Ith *D) / (P pmax *DP Ith *D)](I max -I th )+I th

[0094] Among them, I out is the current, P out is the average laser output power, P p_It0 is the peak power of the first order, t0 is the duration of the first order, f is the representative frequency, P Ith *D is the minimum average power, P pmax *D is the maximum average power, P pmax is the peak power corresponding to the maximum current, P Ith is the peak power corresponding to the minimum current, D is the duty cycle, I max is the maximum current, I th is the minimum current.

[0095] In this embodiment, the fixed duty cycle D=D sp, The frequency is the representative frequency f of the aforementioned frequency range re At this time, adjust the output current so that the average power of the laser output reaches the minimum power (for example, the aforementioned minimum output average power is 0.5W), and record the current at this time as the minimum current I in this frequency range. th Then continue to adjust the output current to make the laser output average power reach the maximum average power (for example, the maximum output average power is 20W), and record the maximum current I at this time.max .

[0096] Based on the fact that average power is equal to peak power multiplied by duty cycle, P in formula ① is Ith *D and P pmax *D has been determined (minimum peak power P Ith and the maximum peak power P pmax (The above example shows that the values ​​of 0.5W and 20W are respectively 0.5W and 20W.) re , so we get P out and I out The user can set different average power P on the screen. out , the required output current can be calculated.

[0097] Based on the above relationship among average power, peak power and duty cycle, the average power output range of various products can be flexibly adapted, which also reflects the advantages of the embodiments of the present invention.

[0098] Change the duty cycle and repeat the above step 3 to obtain the current-average power relationship of the laser at various duty cycles and different frequency ranges.

[0099] Continuing with the previous example, we modify the duty cycle to be D=D mp =10%, D=D lp =20%, repeat step 3 to obtain the linear equation relationship of "current-average power" in different frequency ranges at different duty cycles.

[0100] Based on the above power correction method, the data shown in Table 1 are obtained.

[0101]

[0102]

[0103]

[0104] Table 1

[0105] Three duty cycles are shown in Table 1: sp =5%, D mp =10%, D lp = 20%, the frequency range is 0Hz-150Hz (representing a frequency of 75Hz) and 151Hz-250Hz (representing a frequency of 200Hz), and the average power output range is 0.5W-5W, 0.5W-10W, and 0.5W-20W. The corresponding current values ​​are measured. Furthermore, based on the above formula ①, the relationship between current and average power in different frequency ranges under each duty cycle can be obtained.

[0106] The laser power calibration method for suppressing relaxation oscillations provided in an embodiment of the present invention is applicable to a pulsed laser control method that adds a small step signal for suppressing relaxation oscillations. It not only refers to the current power curve of the laser manufacturer, but also determines the actual current-average power relationship by actually measuring the power output value of the laser, thereby achieving accurate calibration of the laser.

[0107] Furthermore, an embodiment of the present invention also provides the above-mentioned step single pulse energy for suppressing the relaxation oscillation phenomenon.

[0108] First, set the current and duration t0 required to output the small step that suppresses the relaxation oscillation phenomenon, and set the small step optical signal to output at 100 Hz or above (the frequency selection depends mainly on the range and scale of the power meter during the test. If the power meter is very sensitive, a smaller frequency output can be selected. If it is not very sensitive, a larger frequency output can be selected so that the power meter can measure and identify it). Then, based on the fact that average power is equal to pulse energy multiplied by frequency, the average power obtained by the power meter can be divided by the output frequency at this time to obtain the "relaxation oscillation step single pulse energy" E that suppresses the small step of relaxation oscillation. This is recorded in the last row of Table 1.

[0109] Optionally, the single pulse energy is calculated as follows: E = P a_It0 / f or, E=P a_It0* t0

[0110] Where E is the single pulse energy, P a_It0 is the average power of the first order, f is the frequency, and t0 is the duration of the first order.

[0111] Figure 3 FIG2 shows a schematic diagram of the structure of a laser power correction device for suppressing relaxation oscillation according to an embodiment of the present invention, wherein the device comprises:

[0112] The frequency segmentation module 301 is configured to perform the following steps:

[0113] Step 1: Setting the duty cycle of the laser to a first duty cycle and the frequency to a first frequency, adjusting the current so that the average power output by the laser is a preset power, and recording the current value; the waveform of the current includes a first order and a second order, the amplitude of the first order is smaller than the amplitude of the second order, and the amplitude of the laser relaxation oscillation waveform induced by the first order current signal is smaller than a safety threshold;

[0114] Step 2: adjusting the frequency based on the current current value and the first duty cycle so that the average power output by the laser is the preset power, and recording all frequency values ​​to obtain a frequency interval;

[0115] Changing the duty cycle, repeating steps 1 and 2, to obtain frequency intervals of the laser at various duty cycles; each frequency interval corresponds to a representative frequency;

[0116] The power calibration module 302 is configured to perform the following steps:

[0117] Step 3, setting the duty cycle of the laser to a second duty cycle and the frequency to the representative frequency, adjusting the current so that the average power output by the laser is the minimum average power and the maximum average power, and recording the corresponding currents as the minimum current and the maximum current; and determining the current-average power relationship based on the minimum current, the maximum current, the peak power corresponding to the maximum current, the peak power corresponding to the minimum current, the second duty cycle, the peak power corresponding to the first order, the duration of the first order, and the representative frequency;

[0118] The duty cycle is changed, and step three is repeated to obtain the current-average power relationship of the laser at various duty cycles and in different frequency ranges.

[0119] Optionally, the current-average power relationship is as follows:

[0120] I out =[(P out -P p_It0 *t0*fP Ith *D) / (P pmax *DP Ith *D)](I max -I th )+I th

[0121] Among them, I out is the current, P out is the average laser output power, P p_It0 is the peak power of the first order, t0 is the duration of the first order, f is the representative frequency, P Ith *D is the minimum average power, P pmax *D is the maximum average power, P pmax is the peak power corresponding to the maximum current, P Ith is the peak power corresponding to the minimum current, D is the duty cycle, I max is the maximum current, I th is the minimum current.

[0122] An embodiment of the present invention provides a laser, comprising a computer-readable storage medium storing a computer program and a processor. When the computer program is read and executed by the processor, the laser power correction method for suppressing relaxation oscillation is implemented.

[0123] The laser power correction device and laser for suppressing relaxation oscillation provided in the embodiments of the present invention can achieve the same technical effects as the laser power correction method for suppressing relaxation oscillation provided in the above embodiments. To avoid repetition, they will not be described here.

[0124] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be based on the scope defined by the claims.

[0125] Finally, it should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article, or device comprising the element.

[0126] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A laser power calibration method for suppressing relaxation oscillation, characterized in that: include: Step 1: setting the duty cycle of the laser to a first duty cycle and the frequency to a first frequency, adjusting the current so that the average power output by the laser is a preset power, and recording the current current value; The waveform of the current includes a first order and a second order, the amplitude of the first order is smaller than the amplitude of the second order, and the amplitude of the laser relaxation oscillation waveform induced by the current signal of the first order is smaller than a safety threshold; wherein the laser includes a laser diode; Step 2: adjusting the frequency based on the current current value and the first duty cycle so that the average power output by the laser is the preset power, and recording all frequency values ​​to obtain a frequency interval; Changing the duty cycle, repeating steps 1 and 2, to obtain frequency intervals of the laser at various duty cycles; each frequency interval corresponds to a representative frequency; Step 3, setting the duty cycle of the laser to a second duty cycle and the frequency to the representative frequency, adjusting the current so that the average power output by the laser is the minimum average power and the maximum average power, and recording the corresponding currents as the minimum current and the maximum current; and determining the current-average power relationship based on the minimum current, the maximum current, the peak power corresponding to the maximum current, the peak power corresponding to the minimum current, the second duty cycle, the peak power corresponding to the first order, the duration of the first order, and the representative frequency; The duty cycle is changed, and step three is repeated to obtain the current-average power relationship of the laser at various duty cycles and in different frequency ranges.

2. The method according to claim 1, characterized in that The current-average power relationship is as follows: I out =[(P out -P p_It0 *t0*f-P Ith *D) / (P pmax *D-P Ith *D)](I max -I th )+I th Among them, I out is the current, P out is the average laser output power, P p_It0 is the peak power of the first order, t0 is the duration of the first order, f is the representative frequency, P Ith *D is the minimum average power, P pmax *D is the maximum average power, P pmax is the peak power corresponding to the maximum current, P Ith is the peak power corresponding to the minimum current, D is the duty cycle, I max is the maximum current, I th is the minimum current.

3. The method according to claim 1, characterized in that The preset power is the minimum average power or the maximum average power of the laser; or The preset power is a power within a tolerance range between the minimum average power and the maximum average power of the laser.

4. The method according to claim 1, wherein The median value of the frequency interval is set as the corresponding representative frequency.

5. The method according to claim 1, wherein The method further includes determining a single pulse energy of the first order.

6. The method according to claim 5, characterized in that The calculation formula of the single pulse energy is as follows: E=P a_It0 / f Where E is the single pulse energy, P a_It0 is the average power of the first order, and f is the frequency.

7. The method according to claim 5, characterized in that The calculation formula of the single pulse energy is as follows: E=P a_It0* t0 Where E is the single pulse energy, P a_It0 is the average power of the first order, and t0 is the duration of the first order.

8. A laser power calibration device for suppressing relaxation oscillation, characterized in that: include: The frequency segmentation module is used to perform the following steps: Step 1: Setting the duty cycle of the laser to a first duty cycle and the frequency to a first frequency, adjusting the current so that the average power output by the laser is a preset power, and recording the current value; the waveform of the current includes a first order and a second order, the amplitude of the first order is smaller than the amplitude of the second order, and the amplitude of the laser relaxation oscillation waveform induced by the first order current signal is smaller than a safety threshold; wherein the laser includes a laser diode; Step 2: adjusting the frequency based on the current current value and the first duty cycle so that the average power output by the laser is the preset power, and recording all frequency values ​​to obtain a frequency interval; Changing the duty cycle, repeating steps 1 and 2, to obtain frequency intervals of the laser at various duty cycles; each frequency interval corresponds to a representative frequency; The power calibration module is configured to perform the following steps: Step 3, setting the duty cycle of the laser to a second duty cycle and the frequency to the representative frequency, adjusting the current so that the average power output by the laser is the minimum average power and the maximum average power, and recording the corresponding currents as the minimum current and the maximum current; and determining the current-average power relationship based on the minimum current, the maximum current, the peak power corresponding to the maximum current, the peak power corresponding to the minimum current, the second duty cycle, the peak power corresponding to the first order, the duration of the first order, and the representative frequency; The duty cycle is changed, and step three is repeated to obtain the current-average power relationship of the laser at various duty cycles and in different frequency ranges.

9. The device according to claim 8, characterized in that The current-average power relationship is as follows: I out =[(P out -P p_It0 *t0*f-P Ith *D) / (P pmax *D-P Ith *D)](I max -I th )+I th Among them, I out is the current, P out is the average laser output power, P p_It0 is the peak power of the first order, t0 is the duration of the first order, f is the representative frequency, P Ith *D is the minimum average power, P pmax *D is the maximum average power, P pmax is the peak power corresponding to the maximum current, P Ith is the peak power corresponding to the minimum current, D is the duty cycle, I max is the maximum current, I th is the minimum current.

10. A laser, characterized in that: The invention comprises a computer-readable storage medium storing a computer program and a processor, wherein when the computer program is read and executed by the processor, the laser power correction method for suppressing relaxation oscillation according to any one of claims 1 to 7 is implemented.

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