Method and device for suppressing spike pulse of fiber laser

Abstract

The invention provides a method and equipment for suppressing spike pulse of an optical fiber laser, and the method comprises the steps: generating an original pumping signal, and obtaining the amplitude and width of the original pumping signal; acquiring a first laser signal generated based on the original pumping signal, and detecting the amplitude of a spike pulse in the waveform of the first laser signal and the amplitude and delay time when the waveform of the first laser signal is stable; determining the width and the initial amplitude of a suppression signal for suppressing the spike pulse based on the detected data; modulating the original pumping signal by using the suppression signal to generate a second pumping signal; and driving the fiber laser to generate a second laser signal by using the second pumping signal. According to the method for suppressing spike pulse generation of the fiber laser, a square wave for suppressing spike pulse generation is added in front of a pumping source signal square wave, so that a laser signal completely follows a pumping source signal, and standard square wave output is formed.

Description

[0001] This application is a divisional application of the invention patent entitled “A method and device for suppressing fiber laser spike pulses” and application number 202311504138.0, filed with the China National Intellectual Property Administration on November 10, 2023. Technical Field

[0002] The present invention relates to the field of optical fiber lasers, and more particularly to a method and a device for suppressing peak pulses of optical fiber lasers. Background Art

[0003] Fiber oscillators include pump sources, laser media, gain media, and optical elements. The pump source injects energy into the laser medium to excite the activated ions to an excited state. The excited ions generate laser light through stimulated radiation and are amplified by the gain medium in the optical fiber. Optical elements are used to adjust, output, and control the laser beam.

[0004] The duration of the output light pulse of the quasi-continuous fiber laser is relatively long, which is between that of the continuous wave fiber laser and the pulse fiber laser. The quasi-continuous laser usually uses a high-energy pulse pump source as the energy input. The pump source provides energy to the laser medium in the form of pulses, excites the doped particles in the gain fiber, and then passes through the appropriate resonant cavity to produce reflection and enhancement of a specific wavelength, finally forming a quasi-continuous laser output.

[0005] The pulse width of quasi-continuous lasers is usually in the microsecond level or longer, and they have a longer pulse width than pulsed lasers. Quasi-continuous lasers usually have high energy output capabilities. The output of quasi-continuous lasers is relatively stable, and the energy and time interval between pulses are relatively uniform, which can provide a stable light source.

[0006] The pump light source of the oscillator-pumped modulated fiber laser is modulated by the modulator and then injected into the fiber oscillator. In the oscillator, the light is reflected and amplified multiple times, resulting in oscillation and amplification effects, and finally forming laser output. The oscillator structure enables the fiber laser to have a high power conversion efficiency. The optical amplification process in the oscillator structure can effectively convert the pump light energy into laser light energy and reduce energy loss. This enables the fiber laser to provide a higher output power, which is suitable for applications that require high-power lasers, such as material processing and laser communications.

[0007] The moment the pump signal is just loaded on the fiber laser based on the oscillator structure, the laser output is unstable, and a strong pulse output will be formed, with a peak value several times or even dozens of times higher than the stable output, and then the stable output will be achieved. This phenomenon is particularly obvious in the quasi-continuous laser based on oscillator pump modulation, and there will be a strong spike at the beginning of each pulse.

[0008] The generation of spike pulses may have some adverse effects on the application of fiber lasers, such as generating additional noise, reducing the stability of laser output, etc., affecting the stability of the entire application system. Therefore, when designing and optimizing quasi-continuous lasers, some measures need to be taken to suppress the generation of spike pulses.

[0009] Currently, the existing technology generally does not have a good method for suppressing spike pulses. Summary of the invention

[0010] The invention provides a method and a device for suppressing a peak pulse of an optical fiber laser, which effectively suppresses a peak pulse in a laser signal output by the optical fiber laser.

[0011] In a first aspect, the present invention provides a method for suppressing a fiber laser spike pulse, the method comprising: generating an original pump signal, and acquiring the amplitude and width of the original pump signal; Acquire a waveform of a first laser signal generated based on the original pump signal, and detect the amplitude of a peak pulse in the first laser signal waveform, the amplitude of the first laser signal waveform when it is stable, and the delay time relative to the original pump signal; Determine the width and starting amplitude of a suppression signal for suppressing the spike pulse based on the detected amplitude of the original pump signal, the amplitude of the first laser signal when the waveform is stable, the delay time, and the amplitude of the spike pulse; Modulating the original pump signal using the suppression signal to generate a second pump signal; The second pump signal is used to drive the fiber laser to generate a second laser signal.

[0012] In one embodiment of the present invention, the step of determining the width and starting amplitude of the suppression signal for suppressing the spike pulse based on the detected amplitude and delay time of the spike pulse further comprises the following steps: Calculating a first ratio between the amplitude of the first laser signal waveform when it is stable and the amplitude of the spike pulse, and determining the starting amplitude of the suppression signal based on the first ratio and the amplitude of the original pump signal; or Calculating a second ratio between the amplitude of the original pump signal and the amplitude of the spike pulse, and determining a starting amplitude of the suppression signal based on the second ratio and the amplitude of the first laser signal when the waveform is stable; and The delay time is determined as the width of the suppression signal.

[0013] In yet another embodiment of the present invention, the step of determining the starting amplitude of the suppression signal based on the first ratio and the amplitude of the original pump signal further comprises the following steps: multiplying the first ratio by the amplitude of the original pump signal to determine the starting amplitude of the suppression signal; or The step of determining the starting amplitude of the suppression signal based on the second ratio and the amplitude of the first laser signal waveform when it is stable further comprises the following steps: The starting amplitude of the suppression signal is determined by multiplying the second ratio by the amplitude of the first laser signal when the waveform is stable.

[0014] In yet another embodiment of the present invention, wherein the step of modulating the original pump signal using the suppression signal to generate a second pump signal further comprises: The suppression signal is then added to the leading edge of the original pump signal to generate a waveform of a second pump signal.

[0015] In yet another embodiment of the present invention, the step of adding the suppression signal immediately before the leading edge of the original pump signal to generate the waveform of the second pump signal further includes the following steps: The suppression signal rises from the starting amplitude to the amplitude of the original pump signal.

[0016] In yet another embodiment of the present invention, wherein the step of modulating the original pump signal using the suppression signal to generate a second pump signal further comprises: generating the suppression signal upon receiving the original pump signal; Delaying the original pump signal by the width of the suppression signal; The generated suppression signal is added to the delayed original pump signal to obtain the second pump signal.

[0017] In another embodiment of the present invention, wherein the using the suppression signal to modulate the original pump signal to generate a second pump signal further comprises: Determining the suppression signal width as the width of the modulation signal; Determine the result of subtracting the amplitude of the original pump signal from the starting amplitude of the suppression signal as the starting amplitude of the modulation signal; generating the modulation signal upon receiving the original pump signal; The original pump signal is subtracted from the modulated signal to generate a second pump signal.

[0018] In yet another embodiment of the present invention, wherein the step of modulating the original pump signal using the suppression signal to generate a second pump signal further comprises: Determining the suppression signal width as the width of the modulation signal; Determine the result of subtracting the amplitude of the original pump signal from the starting amplitude of the suppression signal as the starting amplitude of the modulation signal; Expanding the width of the original pump signal by the width of the suppression signal; The expanded original pump signal is subtracted from the modulated signal to generate a second pump signal.

[0019] In a second aspect, the present invention also provides a device for suppressing spike pulses of a fiber laser, comprising: an original pump signal generating device, a laser signal detecting device, a second pump signal generating device, a calculating device, and a fiber laser; The original pump signal generating device is used to generate an original pump signal, obtain the amplitude and width of the original pump signal, and feed it back to the calculating device; The laser signal detection device is used to obtain the waveform of the first laser signal generated by the pump light driven by the fiber laser based on the original pump signal, and detect the amplitude of the peak pulse in the first laser signal waveform, the amplitude when the first laser signal waveform is stable, and the delay time relative to the original pump signal, and feed it back to the calculation device; The calculation device determines the width and starting amplitude of the suppression signal for suppressing the spike pulse based on the detected amplitude of the original pump signal, the amplitude of the first laser signal when the waveform is stable, the delay time and the amplitude of the spike pulse; The second pump signal generating device modulates the original pump signal using the suppression signal to generate a second pump signal; The fiber laser is driven by the second pump signal to generate pump light to generate a second laser signal.

[0020] In one embodiment of the present invention, the computing device further includes: The suppression signal amplitude determination device is used to: Calculating a first ratio between the amplitude of the first laser signal waveform when it is stable and the amplitude of the spike pulse, multiplying the first ratio by the amplitude of the original pump signal to determine the starting amplitude of the suppression signal, and feeding it back to the second pump signal generating device; or Calculating a second ratio between the amplitude of the original pump signal and the amplitude of the spike pulse, multiplying the second ratio by the amplitude of the first laser signal waveform when it is stable to determine the starting amplitude of the suppression signal, and feeding back the result to the second pump signal generating device; and The suppression signal width determining device is used to determine the delay time as the width of the suppression signal and feed it back to the second pump signal generating device.

[0021] In another embodiment of the present invention, the second pump signal generating device further comprises a signal generating module, an original pump signal modulating module, and a merging module; The signal generating module generates a suppression signal upon receiving the original pump signal; The original pump signal modulation module is used to delay the original pump signal; The merging module is used for adding the suppression signal to the delayed original pump signal to generate the second pump signal.

[0022] In another embodiment of the present invention, the original pump signal modulation module is used to delay the width of the suppression signal by the original pump signal.

[0023] In another embodiment of the present invention, the computing device further includes: A modulation signal width determining device, used to determine the suppression signal width as the width of the modulation signal, and feed back to the second pump signal generating device; The modulation signal amplitude determination device is used to determine the result of subtracting the amplitude of the original pump signal from the starting amplitude of the suppression signal as the modulation signal starting amplitude, and feed it back to the second pump signal generation device.

[0024] In another embodiment of the present invention, the second pump signal generating device further comprises a signal generating module and a merging module; The signal generating module generates the modulation signal upon receiving the original pump signal; The merging module is used for subtracting the modulation signal from the original pump signal to generate the second pump signal.

[0025] In another embodiment of the present invention, the second pump signal generating device further comprises an original pump signal modulation module, which is used to widen the width of the original pump signal to the width of the suppression signal; The merging module is used for subtracting the modulated signal from the expanded original pump signal to generate the second pump signal.

[0026] The method of suppressing the generation of fiber laser spike pulses of the present invention adds a square wave or other waveform for suppressing the generation of spike pulses before the square wave of the pump source signal. The appropriate height (power) and width (time) are adjusted so that the laser strong pulse peak occurs at the rising edge stage of the main square wave and is submerged in the rising edge of the main square wave, so that the laser signal is completely aligned with the pump source signal to form a standard square wave output. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0028] Figure 1 This is a schematic diagram of the pump signal and output laser signal under ideal conditions.

[0029] Figure 2A It is a schematic diagram of the original pump signal with a standard square wave shape and the output laser signal containing spike pulses in actual situations.

[0030] Figure 2B This is a schematic diagram of the output laser signal containing spike pulses displayed by an oscilloscope for experimental detection.

[0031] Figures 3A-3D It is a schematic diagram of suppressing a spike pulse pump signal and outputting a laser signal provided by an embodiment of the present invention.

[0032] Figures 4A-4E It is a schematic diagram of a method for generating a second pump signal according to the present invention.

[0033] Figure 5 The invention is a device for suppressing the peak pulse of an optical fiber laser.

[0034] Figure 6 The present invention is a flow chart of a method for suppressing fiber laser peak pulses. DETAILED DESCRIPTION

[0035] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. SUMMARY OF THE INVENTION The principles and spirit of the present invention will be described below with reference to several exemplary embodiments. It should be understood that these embodiments are provided only to enable those skilled in the art to better understand and implement the present invention, and are not intended to limit the scope of the present invention in any way. On the contrary, these embodiments are provided to make the present disclosure more thorough and complete, and to fully convey the scope of the present disclosure to those skilled in the art.

[0037] Figure 1 A schematic diagram showing the pump signal and output laser signal under ideal conditions. That is, the output laser signal has no spike pulses, and the pulse width of the pump signal is consistent with the pulse width of the laser signal.

[0038] Figure 2A The actual pump signal and the generated laser signal are shown. Figure 2A The original pump signal shown is the actual pump signal, and the first laser signal is generated by the original pump signal. The figure shows that the first laser signal always lags behind the original pump signal for a period of time. Figure 2AIn the figure, W is used to represent it. Secondly, the first laser signal generates a high-amplitude spike pulse at the rising edge. The amplitude of the spike pulse is Figure 2A In the above formula, H is used to represent Figure 2A The L in represents the amplitude of the first laser signal in a stable state.

[0039] The delay time W is generated because after the pump light emitted by the pump source enters the gain medium, since the gain medium is a rare-earth-doped optical fiber, the pump light is absorbed, and the rare-earth ions that absorb the photon energy undergo energy level transitions and achieve particle number inversion. The inverted particles pass through the resonant cavity, transition from the excited state back to the ground state, release energy, and form a stable laser output. This process takes a certain amount of time.

[0040] The reason for the high-amplitude spike pulses is that when the pump beam just starts to provide energy to the laser medium, the laser medium in the fiber oscillator is still responding, and its gain amplification effect has not yet been established. In this process, excited particles in the laser medium (such as erbium ions in erbium-doped fiber) gradually accumulate, but the laser photon density is low. With the accumulation of excited particles, when the laser medium response in the fiber cavity reaches the critical condition, the weak laser signal generated will be output through the fiber output coupler to form a spike pulse. This is because the accumulation of excited particles is sufficient at this time. Through the stimulated radiation and spontaneous radiation of excited particles, the weak laser signal will be suddenly amplified to form a suddenly enhanced pulse signal. The peak value H of the spike pulse is generally several or dozens of times the amplitude L when the laser signal is stable.

[0041] As time goes by, the excited state particles in the fiber oscillator continue to increase, and the oscillation process gradually stabilizes, producing continuous laser output. Therefore, when the pump is just loaded, the reason for the appearance of the spike pulse is the accumulation of excited state particles and the establishment process of laser oscillation, and then the laser output gradually stabilizes.

[0042] Figure 2B This is a schematic diagram of the output laser signal containing a spike pulse displayed by an oscilloscope for experimental detection. It can be seen from the figure that there is a very strong pulse on the rising edge of the output laser signal, and then the signal waveform tends to be stable.

[0043] The purpose of the present invention is to synchronize the original pump signal with the first laser signal and suppress the generation of high-amplitude spike pulses. That is, the delay time W is reduced and its value is approached to 0. The spike pulse at the rising edge of the main square wave of the first laser signal is close to disappearing, that is, the peak value H of the spike pulse is reduced and H is approached to the size of L.

[0044] Since the generation of spike pulses is related to the sudden increase of pump beam power in the laser medium of the fiber laser, the occurrence of spike pulses can be reduced by controlling the power increase amplitude of the pump beam. Then, the power of the pump beam in the laser medium is gradually increased, so that the excited state particles in the laser medium gradually accumulate slowly, which helps to establish stable laser oscillation.

[0045] The following content will explain the principle of the method for suppressing the generation of spike pulses of the present application.

[0046] The present invention inputs a second pump signal to the pump source, so that the pulse peak is submerged in the rising edge stage of the first laser signal. The second pump signal is generated by modulating the original pump signal, that is, adding a suppression signal with an amplitude (power) of A and a width (time) of K before the original pump signal. Figure 3A As shown, the waveform of the second pump signal includes a portion 301 and a portion 302, and the second laser signal is generated by the second pump signal. The second pump signal portion 301 is generated by the suppression signal, and the second pump signal portion 302 is generated by the original pump signal. In the following, for the convenience of description and correspondence with the figure, the second pump signal portion 301 is referred to as the suppression waveform 301, and the second pump signal portion 302 is referred to as the original pump waveform 302.

[0047] The suppression waveform 301 in the second pump signal first enters the pump source. The pump source drives the pump source based on the current of the suppression waveform 301 to generate a pump beam of corresponding intensity. The pump beam enters the laser medium, and the laser medium begins to respond. The width K of the suppression waveform 301 is just the time from the pump beam entering the laser medium to the completion of the response of the laser medium. When the laser medium reaches the critical condition, the suppression waveform 301 has entered completely, and the pump beam generated by the pump source driven by the original pump waveform 302 begins to enter the laser medium. At this time, a certain degree of excited state particles have accumulated inside the laser medium, and the laser medium begins to produce an amplification effect. The spike pulse generated by the suppression waveform 301 is synchronized with the rising edge of the second laser signal, that is, the spike pulse overlaps with the rising edge of the second laser signal. Since the amplitude (power) of the suppression waveform 301 is less than the amplitude (power) of the original pump waveform 302, the peak value of the spike pulse generated by the suppression waveform 301 is also less than or equal to the amplitude of the second laser signal, which will cause the spike generated by the suppression waveform 301 to be submerged in the rising edge of the second laser signal generated by the original pump waveform 302. Subsequently, the amplitude (power) of the original pump waveform 302 remains unchanged, the laser medium has also completed the response, the second laser signal is synchronized with the original pump waveform 302, and the width B of the second laser signal is the same as the width of the original pump waveform 302, and no additional compensation is required. At this time, the laser medium has formed a stable gain amplification, and the oscillation output of the fiber laser begins to stabilize, so the laser signal will completely follow the pump source signal to form a standard square wave output.

[0048] The suppression waveform 301 may not only be Figure 3A The square wave shown in Figure 3B The ramp waveform shown can also be Figure 3C and Figure 3D As long as the amplitude (power) A and width (time) K of the suppression waveform 301 are appropriate, the peak pulse can be well suppressed.

[0049] The following will describe how the present invention generates the second pump signal and produces the second laser signal based on the second pump signal.

[0050] Since the pulse height and delay time in the laser signal are not the same in each laser, it is necessary to obtain the delay time from loading the pump signal to obtaining the laser signal output through testing in advance. And the pulse height in the laser signal is proportional to the power of the initial loaded pump signal, so the proportional relationship between them can be obtained through testing. To this end, the inventors designed the following test steps: First, load Figure 2AThe original pump signal shown in , detect or directly obtain the amplitude V (power) size and width T (time) of the original pump signal. (Corresponding to Figure 6 Step 601 shown) Second, obtain Figure 2A The waveform of the first laser signal generated based on the original pump signal shown in , and the amplitude H of the peak pulse in the first laser signal waveform, the amplitude L when the first laser signal waveform is stable, and the delay time W relative to the original pump signal are detected. (Corresponding to Figure 6 Step 602 shown) Third, based on the detected amplitude V (power) of the original pump signal, the amplitude H of the spike pulse, and the amplitude L of the first laser signal waveform when it is stable, determine the starting amplitude A of the suppression signal for suppressing the spike pulse; based on the delay time W, determine the width K of the suppression signal for suppressing the spike pulse. (Corresponding to Figure 6 Step 603 shown) The width K of the suppression signal is the delay time W of the spike pulse relative to the original pump signal. Calculate the first ratio of the amplitude L of the first laser signal waveform when it is stable to the amplitude H of the spike pulse. , the first ratio The result obtained by multiplying the amplitude V of the original pump signal determines the starting amplitude A of the suppression signal. Alternatively, the second ratio of the amplitude V of the original pump signal and the amplitude H of the spike pulse is calculated. , based on the second ratio The result obtained by multiplying the amplitude L of the first laser signal when the waveform is stable determines the starting amplitude A of the suppression signal, that is, A=(V*L) / H.

[0051] For example: Assume that the width of the original pump signal is 50 nanoseconds (ns) and the amplitude is 5 watts (W). The width of the first laser signal is 40ns and the amplitude is 10W. The delay time of the spike pulse is 10ns and the amplitude is 25W. Please note that the amplitude unit of the pump signal may be voltage (V).

[0052] The width of the suppression signal is set to be equal to the delay time of the spike pulse, that is, 10ns. The first ratio of the amplitude 10w of the first laser signal waveform when it is stable to the amplitude 25w of the spike pulse , multiplying the first ratio by the amplitude 5w of the original pump signal to obtain a starting amplitude of the suppression signal of 2w; or multiplying the second ratio of the amplitude 5w of the original pump signal to the amplitude 25w of the spike pulse by Multiplying by the amplitude 10w of the first laser signal waveform when it is stable, the starting amplitude of the suppression signal is also calculated to be 2w.

[0053] In the normal working stage, the suppression signal is used to modulate the original pump signal to generate a second pump signal. In this step, there are two methods to generate the second pump signal, and the two methods will be described below. (Corresponding to Figure 6 Step 604 shown) Method 1: After the starting amplitude A and width K of the suppression signal are determined, the suppression signal is generated, wherein the suppression signal rises from the starting amplitude A to the amplitude V of the original pump signal. The waveform of the suppression signal can be a square wave, a ramp, or other curve transition waveforms, and the specific transition waveform that can achieve a better suppression effect can be obtained through experiments.

[0054] When the original pump signal is loaded, the suppression signal starts to be generated, and then the original pump signal is delayed by the width K of the suppression signal. Figures 4A-4D As shown, the generated suppression signal is added to the delayed original pump signal to obtain the second pump signal.

[0055] Method 2: After the starting amplitude A and width K of the suppression signal are determined, the modulation signal is generated. The width of the modulation signal is set to the suppression signal width K. The result of subtracting the amplitude V of the original pump signal from the starting amplitude A of the suppression signal is determined as the starting amplitude of the modulation signal.

[0056] For example: Assume that the width of the original pump signal is 50 nanoseconds (ns) and the amplitude is 5 watts (W). The width of the first laser signal is 40ns and the amplitude is 10W. The delay time of the spike pulse is 10ns and the amplitude is 25W. As mentioned above, the width of the suppression signal is calculated to be 10ns and its starting amplitude is 2W.

[0057] Then, the width of the modulation signal is 10ns, and the result of subtracting the amplitude of the original pump signal 5w from the starting amplitude of the suppression signal is 3w, so the starting amplitude of the modulation signal is also 3w.

[0058] The modulation signal is generated synchronously when the original pump signal is received. Figure 4E As shown, the original pump signal is subtracted from the modulation signal to generate a second pump signal. The width of the steady-state pump waveform 302 in the second pump signal generated based on the modulation signal and the original pump signal is the width T of the original pump signal minus the width K of the suppression signal.

[0059] If the width of the steady-state pump waveform 302 in the generated second pump signal is desired to be the same as the width of the original pump signal, then the width of the original pump signal needs to be widened by the width of the suppression signal. That is, the width of the widened original pump signal is equal to the width T of the original pump signal plus the width K of the suppression signal. Then, the widened original pump signal is subtracted from the modulation signal to generate the second pump signal. The advantage of the second method over the first method is that no delay circuit is required to delay the original pump signal.

[0060] The second pump signal is used to drive the fiber laser to generate a second laser signal. (Corresponding to Figure 6 Step 605 shown) The above two examples explain how to obtain the parameters of the suppression waveform 301 in the second pump signal through specific calculations, and how to generate the second pump signal with the suppression signal by broadening or delaying the original pump signal and performing subtraction or addition operations with the modulated signal or the suppression signal generated separately. In fact, the parameters of the suppression waveform 301 can also be obtained by experimental debugging methods, and the second pump signal with the suppression signal can be generated directly by a function signal generator.

[0061] If the width and the starting amplitude of the suppression waveform 301 are determined and input into a function signal generator, the second pump signal having the suppression signal can be directly obtained without the need for additional operations.

[0062] To obtain the parameters of the suppression waveform 301 by the experimental debugging method, it is necessary to first estimate the width and starting amplitude of the suppression waveform 301, input the estimated value into the waveform function generator to directly generate the waveform of the second pump signal with the suppression signal, and use the second pump signal to drive the fiber laser to generate a laser signal. Constantly change the width and starting amplitude of the suppression waveform 301 input into the function signal generator, and observe the relative position and suppression of the peak pulse and the square wave in the laser signal waveform output by the fiber laser, until it is observed that the laser signal output by the fiber laser is consistent with the second laser signal mentioned above, and then stop changing. At this time, the numerical value recorded in the function signal generator is the determined value of the required suppression waveform 301 width and starting amplitude.

[0063] During the observation process, if the spike pulse appears earlier than the rising edge of the square wave, the width of the suppression waveform 301 is gradually increased, and if the spike pulse lags behind the rising edge of the square wave, the width of the suppression waveform 301 is reduced. If the amplitude of the spike pulse is higher than the amplitude of the square wave, the initial amplitude of the suppression waveform 301 is reduced.

[0064] The specific method of generating the second pump signal listed above depends on the actual needs of the user and is not limited to the specific implementation described in this article.

[0065] Exemplary Devices After introducing the method of the exemplary embodiment of the present invention, next, refer to Figure 5 The exemplary embodiments of the present invention can be implemented by the following means. Figure 5 As shown, the device includes: an original pump signal generating device 501, a laser signal detecting device 504, a second pump signal generating device 502, a calculating device 505 and a fiber laser 503, wherein the connection mode is as follows: The original pump signal generating device 501 is used to generate an original pump signal. Figure 5 As shown in FIG, line a is opened, line b is closed, and the original pump signal generating device 501 directly transmits the generated original pump signal to the fiber laser 503 through line a. At the same time, the amplitude and width of the original pump signal are obtained, and the amplitude and width of the original pump signal are fed back to the calculation device 505.

[0066] After the fiber laser 503 receives the original pump signal transmitted from line a, the original pump signal drives the pump source in the fiber laser 503 to generate a corresponding pump beam, and the pump beam is coupled to the optical cavity through the optical coupler in the fiber laser 503, and the laser medium in the optical cavity begins to amplify the gain and output the first laser signal.

[0067] The laser signal detection device 504 is connected to the output end of the fiber laser 503, obtains the waveform of the first laser signal generated by the pump light generated based on the original pump signal to drive the fiber laser 503, and detects the amplitude of the peak pulse in the first laser signal waveform, the amplitude when the first laser signal waveform is stable, and the delay time relative to the original pump signal, and feeds it back to the calculation device 505.

[0068] After the above operations are completed, the normal working stage is entered. The original pump signal generating device 501 closes line a and no longer transmits the original pump signal to the fiber laser 503, and opens line b to transmit the original pump signal to the second pump signal generating device.

[0069] The calculation device 505 receives the amplitude and width of the original pump signal transmitted from the original pump signal generating device 501, and receives the amplitude of the peak pulse in the first laser signal waveform, the amplitude when the first laser signal waveform is stable, and the delay time relative to the original pump signal transmitted from the laser signal detecting device 504. Based on the received data, the width and starting amplitude of the modulation signal, as well as the width and starting amplitude of the suppression signal are calculated.

[0070] The calculation device 505 includes: a suppression signal width determination device 506 and a suppression signal amplitude determination device 507 .

[0071] The suppression signal width determination device 506 is used to determine the width of the suppression signal, determine the delay time as the width of the suppression signal, and feed back the width of the suppression signal to the second pump signal generation device 502 .

[0072] The suppression signal amplitude determination device 507 is used to determine the starting amplitude of the suppression signal. The first ratio between the amplitude of the first laser signal when the waveform is stable and the amplitude of the spike pulse is calculated, the first ratio is multiplied by the amplitude of the original pump signal to determine the starting amplitude of the suppression signal, and the starting amplitude of the suppression signal is fed back to the second pump signal generation device 502; or the second ratio between the amplitude of the original pump signal and the amplitude of the spike pulse is calculated, the second ratio is multiplied by the amplitude of the first laser signal when the waveform is stable to determine the starting amplitude of the suppression signal, and the starting amplitude of the suppression signal is fed back to the second pump signal generation device 502.

[0073] The second pump signal generating device 502 modulates the original pump signal using the suppression signal to generate a second pump signal. The second pump signal generating device 502 includes a signal generating module 511 , an original pump signal modulating module 510 , and a merging module 512 .

[0074] The original pump signal modulation module 510 receives the original pump signal transmitted from the original pump signal generating device 501 through line b, and also receives the width of the suppression signal transmitted from the suppression signal width determining device 506. The original pump signal modulation module 510 delays the original pump signal by the width of the suppression signal. For example, if the width of the suppression signal is 10ns, the original pump signal is delayed by 10ns. The delayed original pump signal is sent to the merging module 512.

[0075] The signal generating module 511 receives the width of the suppression signal transmitted from the suppression signal width determining device 506, and receives the starting amplitude of the suppression signal transmitted from the suppression signal amplitude determining device 507. Then, based on these two parameters, the suppression signal is generated when the original pump signal modulating module 510 receives the original pump signal, and the suppression signal is sent to the combining module 512 at the same time.

[0076] The merging module 512 adds the received suppression signal to the delayed original pump signal to generate the second pump signal.

[0077] The calculation device 505 further includes: a modulation signal width determination device 508 and a modulation signal amplitude determination device 509.

[0078] The modulation signal width determining device 508 is used to determine the width of the modulation signal, determine the delay time as the width of the modulation signal, and feed back the width of the modulation signal to the second pump signal generating device 502 .

[0079] The modulation signal amplitude determination device 509 is used to determine the result of subtracting the amplitude of the original pump signal from the starting amplitude of the suppression signal as the modulation signal starting amplitude, and feed back the modulation signal starting amplitude to the second pump signal generation device 502 .

[0080] The original pump signal modulation module 510 receives the original pump signal transmitted from the original pump signal generation device 501 through line b, and sends the original pump signal to the merging module 512 .

[0081] The signal generating module 511 receives the width of the modulation signal transmitted from the modulation signal width determining device 508, and receives the starting amplitude of the modulation signal transmitted from the modulation signal amplitude determining device 509. Then, based on these two parameters, the modulation signal is generated when the original pump signal modulation module 510 receives the original pump signal, and the modulation signal is sent to the combining module 512.

[0082] The merging module 512 subtracts the received modulation signal from the original pump signal to generate the second pump signal.

[0083] The width of the original pump waveform 302 in the second pump signal generated in the merging module 512 based on the original pump signal output by the original pump signal modulation module 510 and the modulation signal output by the signal generation module 511 is the width of the original pump signal minus the width of the suppression signal. If it is desired that the width of the original pump waveform 302 of the second pump signal output by the merging module is the width of the original pump signal, the merging module 512, the signal generation module 511 and the original pump signal modulation module 510 in the second pump signal generation device 502 perform the following operations: The original pump signal modulation module 510 receives the original pump signal transmitted from the original pump signal generating device 501 through line b, and also receives the width of the suppression signal transmitted from the suppression signal width determining device 506. The original pump signal modulation module 510 widens the width of the original pump signal to the width of the suppression signal. For example, if the width of the suppression signal is 10ns and the width of the original pump signal is 50ns, then the width of the original pump signal is widened to 60ns. The widened original pump signal is sent to the merging module 512.

[0084] The signal generating module 511 receives the width of the modulation signal transmitted from the modulation signal width determining device 508, and receives the starting amplitude of the modulation signal transmitted from the modulation signal amplitude determining device 509. Then, based on these two parameters, the modulation signal is generated when the original pump signal modulation module 510 receives the original pump signal, and the modulation signal is sent to the combining module 512.

[0085] The merging module 512 subtracts the received modulated signal from the expanded original pump signal to generate the second pump signal.

[0086] The fiber laser 503 is driven by the second pump signal to generate pump light to generate a second laser signal.

[0087] The present invention is not limited to the above-mentioned connection mode, and suitable equipment and connection mode can be selected according to specific applications and equipment requirements. In practical applications, some debugging and optimization may be required to ensure the normal operation of the device and obtain the required pump signal characteristics.

[0088] The present invention is not limited to the specific embodiments disclosed, and the division of various aspects does not mean that the features in these aspects cannot be combined to benefit. This division is only for the convenience of expression. The present invention is intended to cover various modifications and equivalent arrangements included in the spirit and scope of the attached claims.

[0089] The present invention provides: 1. A method for suppressing fiber laser spike pulses, comprising: generating an original pump signal, and acquiring the amplitude and width of the original pump signal; Determining preset parameters based on a first laser signal generated by the original pump signal; Determining the width and starting amplitude of a suppression signal for suppressing a peak pulse in the first laser signal waveform based on the preset parameters; Modulating the original pump signal using the suppression signal to generate a second pump signal; The second pump signal is used to drive the fiber laser to generate a second laser signal.

[0090] 2. According to the method described in item 1, the step of determining the preset parameters of the first laser signal generated based on the original pump signal further comprises the following steps: Acquire the waveform of the first laser signal, and detect the amplitude of the peak pulse in the first laser signal waveform, the amplitude of the first laser signal waveform when it is stable, and the delay time relative to the original pump signal; The detected amplitude of the original pump signal, the amplitude of the first laser signal when the waveform is stable, the delay time and the amplitude of the peak pulse are determined as the preset parameters.

[0091] 3. According to the method described in item 1, the step of determining the width and starting amplitude of the suppression signal for suppressing the spike pulse based on the preset parameters further comprises the following steps: Calculating a first ratio between the amplitude of the first laser signal waveform when it is stable and the amplitude of the spike pulse, and determining the starting amplitude of the suppression signal based on the first ratio and the amplitude of the original pump signal; or Calculating a second ratio between the amplitude of the original pump signal and the amplitude of the spike pulse, and determining a starting amplitude of the suppression signal based on the second ratio and the amplitude of the first laser signal when the waveform is stable; and The delay time is determined as the width of the suppression signal.

[0092] 4. According to the method of item 3, the step of determining the starting amplitude of the suppression signal based on the first ratio and the amplitude of the original pump signal further comprises the following steps: multiplying the first ratio by the amplitude of the original pump signal to determine the starting amplitude of the suppression signal; or The step of determining the starting amplitude of the suppression signal based on the second ratio and the amplitude of the first laser signal waveform when it is stable further comprises the following steps: The starting amplitude of the suppression signal is determined by multiplying the second ratio by the amplitude of the first laser signal when the waveform is stable.

[0093] 5. According to the method of item 1, wherein the step of modulating the original pump signal using the suppression signal to generate a second pump signal further comprises: The suppression signal is then added to the leading edge of the original pump signal to generate a waveform of a second pump signal.

[0094] 6. According to the method described in item 5, the step of adding the suppression signal to the leading edge of the original pump signal to generate the waveform of the second pump signal further comprises the following steps: The suppression signal rises from the starting amplitude to the amplitude of the original pump signal.

[0095] 7. The method according to any one of items 1 to 6, wherein the step of modulating the original pump signal using the suppression signal to generate a second pump signal further comprises: generating the suppression signal upon receiving the original pump signal; Delaying the original pump signal by the width of the suppression signal; The generated suppression signal is added to the delayed original pump signal to obtain the second pump signal.

[0096] 8. The method according to item 1, wherein the step of modulating the original pump signal using the suppression signal to generate a second pump signal further comprises: Determining the suppression signal width as the width of the modulation signal; Determine the result of subtracting the amplitude of the original pump signal from the starting amplitude of the suppression signal as the starting amplitude of the modulation signal; generating the modulation signal upon receiving the original pump signal; The original pump signal is subtracted from the modulated signal to generate a second pump signal.

[0097] 9. The method according to item 1, wherein the step of modulating the original pump signal using the suppression signal to generate a second pump signal further comprises: Determining the suppression signal width as the width of the modulation signal; Determine the result of subtracting the amplitude of the original pump signal from the starting amplitude of the suppression signal as the starting amplitude of the modulation signal; Expanding the width of the original pump signal by the width of the suppression signal; The expanded original pump signal is subtracted from the modulated signal to generate a second pump signal.

[0098] 10. A device for suppressing fiber laser spike pulses, comprising: An original pump signal generating device, a laser signal detecting device, a second pump signal generating device, a calculating device and a fiber laser; The original pump signal generating device is used to generate an original pump signal, obtain the amplitude and width of the original pump signal, and feed it back to the calculating device; The laser signal detection device determines a preset parameter based on the first laser signal generated by the original pump signal, and feeds the preset parameter back to the calculation device; The computing device determines the width and starting amplitude of the suppression signal for suppressing the spike pulse based on the preset parameters; The second pump signal generating device modulates the original pump signal using the suppression signal to generate a second pump signal; The fiber laser is driven by the second pump signal to generate pump light to generate a second laser signal.

[0099] 11. According to the device described in item 10, the laser signal detection device also includes: Acquire a waveform of a first laser signal generated based on the original pump signal, and detect the amplitude of a peak pulse in the first laser signal waveform, the amplitude of the first laser signal waveform when it is stable, and the delay time relative to the original pump signal; The detected amplitude of the original pump signal, the amplitude of the first laser signal when the waveform is stable, the delay time and the amplitude of the peak pulse are determined as the preset parameters.

[0100] 12. According to the device described in item 10, the computing device also includes: The suppression signal amplitude determination device is used to: Calculating a first ratio between the amplitude of the first laser signal waveform when it is stable and the amplitude of the spike pulse, multiplying the first ratio by the amplitude of the original pump signal to determine the starting amplitude of the suppression signal, and feeding it back to the second pump signal generating device; or Calculating a second ratio between the amplitude of the original pump signal and the amplitude of the spike pulse, multiplying the second ratio by the amplitude of the first laser signal waveform when it is stable to determine the starting amplitude of the suppression signal, and feeding back the result to the second pump signal generating device; and The suppression signal width determining device is used to determine the delay time as the width of the suppression signal and feed it back to the second pump signal generating device.

[0101] 13. The device according to item 12, wherein the second pump signal generating device further comprises a signal generating module, an original pump signal modulating module, and a merging module; The signal generating module generates a suppression signal upon receiving the original pump signal; The original pump signal modulation module is used to delay the original pump signal; The merging module is used for adding the suppression signal to the delayed original pump signal to generate the second pump signal.

[0102] 14. The device according to item 13, wherein the original pump signal modulation module is used for The original pump signal is delayed by the width of the suppression signal.

[0103] 15. According to the device described in item 12, the computing device also includes: A modulation signal width determining device, used to determine the suppression signal width as the width of the modulation signal, and feed back to the second pump signal generating device; The modulation signal amplitude determination device is used to determine the result of subtracting the amplitude of the original pump signal from the starting amplitude of the suppression signal as the modulation signal starting amplitude, and feed it back to the second pump signal generation device.

[0104] 16. The device according to item 15, wherein the second pump signal generating device further comprises a signal generating module and a merging module; The signal generating module generates the modulation signal upon receiving the original pump signal; The merging module is used for subtracting the modulation signal from the original pump signal to generate the second pump signal.

[0105] 17. The device according to item 15, wherein the second pump signal generating device further comprises an original pump signal modulation module, which is used to widen the width of the original pump signal to the width of the suppression signal; The merging module is used for subtracting the modulated signal from the expanded original pump signal to generate the second pump signal.

Claims

1. A method for suppressing fiber laser spike pulses, comprising: generating an original pump signal, and acquiring the amplitude and width of the original pump signal; Determining preset parameters based on a first laser signal generated by the original pump signal; Determining the width and starting amplitude of a suppression signal for suppressing a peak pulse in the first laser signal waveform based on the preset parameters; Modulating the original pump signal using the suppression signal to generate a second pump signal, wherein the starting amplitude of the second pump signal is smaller than that of the original pump signal and greater than 0; The second pump signal is used to drive the optical fiber laser to generate a second laser signal, so as to suppress a peak pulse of the generated laser signal waveform.

2. The method according to claim 1, wherein the step of determining the preset parameters of the first laser signal generated based on the original pump signal further comprises the following steps: Acquire the waveform of the first laser signal, and detect the amplitude of the peak pulse in the first laser signal waveform, the amplitude of the first laser signal waveform when it is stable, and the delay time relative to the original pump signal; The detected amplitude of the original pump signal, the amplitude of the first laser signal when the waveform is stable, the delay time and the amplitude of the peak pulse are determined as the preset parameters.

3. The method according to claim 1, wherein the step of determining the width and starting amplitude of the suppression signal for suppressing the spike pulse based on the preset parameters further comprises the following steps: Calculating a first ratio between the amplitude of the first laser signal waveform when it is stable and the amplitude of the spike pulse, and determining the starting amplitude of the suppression signal based on the first ratio and the amplitude of the original pump signal; or Calculating a second ratio between the amplitude of the original pump signal and the amplitude of the spike pulse, and determining a starting amplitude of the suppression signal based on the second ratio and the amplitude of the first laser signal when the waveform is stable; and The delay time is determined as the width of the suppression signal.

4. The method according to claim 1, wherein the step of determining the starting amplitude of the suppression signal based on the first ratio and the amplitude of the original pump signal further comprises the following steps: multiplying the first ratio by the amplitude of the original pump signal to determine the starting amplitude of the suppression signal; or The step of determining the starting amplitude of the suppression signal based on the second ratio and the amplitude of the first laser signal waveform when it is stable further comprises the following steps: The starting amplitude of the suppression signal is determined by multiplying the second ratio by the amplitude of the first laser signal when the waveform is stable.

5. The method of claim 1, wherein the step of modulating the original pump signal using the suppression signal to generate a second pump signal further comprises: The suppression signal is then added to the leading edge of the original pump signal to generate a waveform of a second pump signal.

6. The method according to any one of claims 1 to 5, wherein the step of modulating the original pump signal using the suppression signal to generate a second pump signal further comprises: generating the suppression signal upon receiving the original pump signal; Delaying the original pump signal by the width of the suppression signal; The generated suppression signal is added to the delayed original pump signal to obtain the second pump signal.

7. A device for suppressing fiber laser spike pulses, comprising: An original pump signal generating device, a laser signal detecting device, a second pump signal generating device, a calculating device and a fiber laser; The original pump signal generating device is used to generate an original pump signal, obtain the amplitude and width of the original pump signal, and feed it back to the calculating device; The laser signal detection device determines a preset parameter based on the first laser signal generated by the original pump signal, and feeds the preset parameter back to the calculation device; The computing device determines the width and starting amplitude of the suppression signal for suppressing the spike pulse based on the preset parameters; The second pump signal generating device modulates the original pump signal using the suppression signal to generate a second pump signal, wherein the starting amplitude of the second pump signal is smaller than that of the original pump signal and greater than 0; The optical fiber laser is driven by the second pump signal to generate pump light to generate a second laser signal, so as to suppress a peak pulse of the generated laser signal waveform.

8. The device according to claim 7, wherein the laser signal detection device further comprises: Acquire a waveform of a first laser signal generated based on the original pump signal, and detect the amplitude of a peak pulse in the first laser signal waveform, the amplitude of the first laser signal waveform when it is stable, and the delay time relative to the original pump signal; The detected amplitude of the original pump signal, the amplitude of the first laser signal when the waveform is stable, the delay time and the amplitude of the peak pulse are determined as the preset parameters.

9. The apparatus of claim 7, wherein: The computing device further comprises: The suppression signal amplitude determination device is used to: Calculating a first ratio between the amplitude of the first laser signal waveform when it is stable and the amplitude of the spike pulse, multiplying the first ratio by the amplitude of the original pump signal to determine the starting amplitude of the suppression signal, and feeding it back to the second pump signal generating device; or Calculating a second ratio between the amplitude of the original pump signal and the amplitude of the spike pulse, multiplying the second ratio by the amplitude of the first laser signal waveform when it is stable to determine the starting amplitude of the suppression signal, and feeding back the result to the second pump signal generating device; The suppression signal width determining device is used to determine the delay time as the width of the suppression signal and feed it back to the second pump signal generating device.

10. The device as claimed in claim 7, wherein the second pump signal generating device further comprises a signal generating module, an original pump signal modulating module, and a merging module; The signal generating module generates a suppression signal upon receiving the original pump signal; The original pump signal modulation module is used to delay the original pump signal; The merging module is used for adding the suppression signal to the delayed original pump signal to generate the second pump signal.

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