The application discloses a method and equipment for suppressing spike pulse of a fiber laser, which is submitted by China intellectual property office on the 11 th and 10 th of 2023, and is a divisional application of an application patent with the application number 202311504138.0.
Disclosure of Invention
The invention provides a method and equipment for inhibiting spike pulse of an optical fiber laser, which effectively realize the inhibition of spike pulse in laser signals output by the optical fiber laser.
In a first aspect, the present invention provides a method of suppressing a fibre laser spike, the method comprising:
Generating an original pumping signal and acquiring the amplitude and the width of the original pumping signal;
acquiring a waveform of a first laser signal generated based on the original pump signal, and detecting the amplitude of spike pulses in the waveform of the first laser signal, the amplitude when the waveform of the first laser signal is stable and the delay time relative to the original pump signal;
determining a width and a starting amplitude of a suppression signal for suppressing the spike based on the detected amplitude of the original pump signal, the amplitude when the first laser signal waveform is stable, the delay time, and the amplitude of the spike;
modulating the original pump signal by using the suppression signal to generate a second pump signal;
and driving the fiber laser to generate a second laser signal by using the second pump signal.
In one embodiment of the present invention, wherein said determining the width and the starting amplitude of the suppression signal for suppressing said spike based on the detected amplitude and delay time of said spike further comprises the steps of:
calculating a first ratio of the amplitude of the first laser signal waveform at stabilization to the amplitude of the spike, determining a starting amplitude of the quench signal based on the first ratio and the amplitude of the original pump signal, or
Calculating a second ratio of the amplitude of the original pump signal to the amplitude of the spike pulse, determining a starting amplitude of the quench 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.
In a further embodiment of the invention, wherein said determining the starting amplitude of the suppression signal based on the first ratio and the amplitude of the original pump signal further comprises the steps of:
Multiplying the first ratio by the amplitude of the original pump signal to determine the initial amplitude of the suppression signal, or
The determining the starting amplitude of the suppression signal based on the second ratio and the amplitude of the first laser signal waveform when stable further comprises the steps of:
multiplying the second ratio by the amplitude of the first laser signal when the waveform is stable determines the starting amplitude of the quench signal.
In yet another embodiment of the present invention, wherein said modulating said original pump signal with said suppression signal, generating a second pump signal further comprises:
a waveform of a second pump signal is then generated by adding the suppression signal to the front edge of the original pump signal.
In a further embodiment of the present invention, wherein said generating a waveform of a second pump signal immediately following adding said suppression signal at a leading edge of said original pump signal further comprises the steps of:
the quench signal rises from the starting amplitude to the amplitude of the original pump signal.
In yet another embodiment of the present invention, wherein said modulating said original pump signal with said suppression signal, generating a second pump signal further comprises:
Generating the quench signal upon receipt of the original pump signal;
Delaying the original pump signal by the width of the inhibit signal;
And adding the generated inhibition signal and the delayed original pump signal to obtain the second pump signal.
In another embodiment of the present invention, wherein said modulating said original pump signal with said suppression signal, generating a second pump signal further comprises:
determining the width of the suppression signal as the width of the modulation signal;
Determining the result of subtracting the initial amplitude of the suppression signal from the amplitude of the original pump signal as the initial amplitude of the modulation signal;
generating the modulation signal upon receiving the original pump signal;
And subtracting the original pump signal from the modulation signal to generate a second pump signal.
In yet another embodiment of the present invention, wherein said modulating said original pump signal with said suppression signal, generating a second pump signal further comprises:
determining the width of the suppression signal as the width of the modulation signal;
Determining the result of subtracting the initial amplitude of the suppression signal from the amplitude of the original pump signal as the initial amplitude of the modulation signal;
Widening the width of the original pump signal by the width of the suppression signal;
and subtracting the widened original pump signal from the modulation signal to generate a second pump signal.
In a second aspect, the invention also provides a device for suppressing spike pulse of the fiber laser, which comprises an original pump signal generating device, a laser signal detecting device, a second pump signal generating device, a calculating device and the fiber laser;
The original pump signal generating device is used for generating an original pump signal, obtaining the amplitude and the width of the original pump signal and feeding the original pump signal back to the computing device;
The laser signal detection device is used for acquiring a waveform of a first laser signal generated by generating pump light based on the original pump signal to drive the fiber laser, detecting the amplitude of spike pulse in the waveform of the first laser signal, the amplitude of the waveform of the first laser signal when stable and the delay time relative to the original pump signal, and feeding back the waveform to the calculation device;
the computing means determines a width and a starting amplitude of a suppression signal for suppressing the spike based on the detected amplitude of the original pump signal, the amplitude when the first laser signal waveform is stable, the delay time, and the amplitude of the spike;
The second pump signal generating device modulates the original pump signal by using the suppression signal to generate a second pump signal;
the fiber laser generates a second laser signal by using the second pump signal to drive and generate pump light.
In one embodiment of the invention, the computing device further comprises:
a suppression signal amplitude determining means for:
calculating a first ratio of the amplitude of the first laser signal waveform stabilized to the amplitude of the spike pulse, multiplying the first ratio by the amplitude of the original pump signal to determine the initial amplitude of the suppression signal, and feeding back to the second pump signal generating device, or
Calculating a second ratio of the amplitude of the original pumping signal to the amplitude of the spike pulse, multiplying the second ratio by the amplitude of the first laser signal when the waveform of the first laser signal is stable to determine the initial amplitude of the suppression signal, and feeding back to a second pumping signal generating device, and
And a suppression signal width determining means for determining the delay time as the width of the suppression signal and feeding back to the second pump signal generating means.
In another embodiment of the present invention, the second pump signal generating device further includes a signal generating module, an original pump signal modulating module, and a combining module;
the signal generation module generates a suppression signal when the original pump signal is received;
The original pump signal modulation module is used for delaying an original pump signal;
the combining module is used for adding the suppression signal and the delayed original pump signal to generate the second pump signal.
In another embodiment of the present invention, the original pump signal modulation module is configured to delay the original pump signal by a width of the suppression signal.
In another embodiment of the present invention, the computing device further comprises:
Modulation signal width determining means for determining the suppression signal width as the width of the modulation signal and feeding back to the second pump signal generating means;
And the modulation signal amplitude determining device is used for determining the result of subtracting the initial amplitude of the suppression signal from the amplitude of the original pump signal as the initial amplitude of the modulation signal and feeding back the initial amplitude of the modulation signal to the second pump signal generating device.
In another embodiment of the present invention, the second pump signal generating device further includes a signal generating module and a combining module;
The signal generation module generates the modulation signal when receiving the original pump signal;
The combining module is used for subtracting the modulating signal from the original pumping signal to generate the second pumping signal.
In another embodiment of the present invention, wherein the second pump signal generating means further comprises an original pump signal modulating module for widening the width of the original pump signal by the suppression signal width;
the combining module is used for subtracting the modulated signal from the widened original pump signal to generate the second pump signal.
The method for suppressing the spike pulse of the fiber laser is realized by adding a square wave for suppressing the spike pulse, or other waveforms, before the square wave of the pumping source signal. And adjusting proper height (power) and width (time) to enable the strong pulse peak of the laser to occur in the rising edge stage of the main wave and submerge in the rising edge of the main wave, so that the laser signal completely coincides with the pump source signal and forms standard square wave output.
Detailed Description
The technical scheme of the invention is further described in detail through the drawings and the 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 presented merely to enable those skilled in the art to better understand and practice the invention and are not intended to limit the scope of the invention in any way. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.
Fig. 1 shows a schematic diagram of the pump signal and the output laser signal in an ideal case. That is, the output laser signal has no spike pulse, and the pulse width of the pumping signal is identical to that of the laser signal.
Fig. 2A shows the actual pump signal and the generated laser signal. The original pump signal shown in fig. 2A is the actual pump signal, from which the first laser signal is generated. The first laser signal is shown always to lag behind the original pump signal by a delay time indicated by W in fig. 2A. Second, the first laser signal produces a high amplitude spike at the rising edge, the amplitude of the spike being denoted by H in fig. 2A, and L in fig. 2A representing the amplitude of the first laser signal at steady state.
The delay time W is generated because after the pump light emitted by the pump source enters the gain medium, the gain medium is a rare earth element doped optical fiber, so that the pump light is absorbed, the rare earth ions absorbing photon energy undergo energy level transition and realize particle number inversion, the inverted particles pass through the resonant cavity, the excited state transitions back to the ground state, energy is released, and stable laser output is formed, and a certain time is needed in the process.
The reason for the high amplitude spike is that when the pump beam just begins to supply energy to the lasing medium, the lasing medium in the fiber oscillator is still responding and its gain amplification effect has not been established. During this process, excited state particles in the lasing medium (e.g., erbium ions in erbium doped fibers) gradually accumulate, but the laser photon density is lower. Along with the accumulation of excited state particles, when the response of a laser medium in the optical fiber cavity reaches a critical condition, a generated weak laser signal can be output through the optical fiber output coupler to form spike pulse. This is because the accumulation of the excited particles is sufficient, and the weak laser signal is suddenly amplified by the processes of stimulated emission and spontaneous emission of the excited particles, so that a suddenly enhanced pulse signal is formed. The peak value H of the spike is typically several or tens of times the amplitude L at which the laser signal is stable.
Over time, the excited particles in the fiber oscillator continue to increase, and the oscillation process gradually stabilizes, producing a continuous laser output. Thus, the cause of the spike occurring just before the pump is loaded is the accumulation of excited particles and the build-up process of laser oscillation, followed by a gradual stabilization of the laser output.
Fig. 2B is a schematic diagram of an output laser signal containing spikes shown by an oscilloscope for experimental detection. It can be seen from the figure that there is a strong pulse at the rising edge of the output laser signal, and then the signal waveform tends to be smooth.
The object of the invention is to synchronize the original pump signal with the first laser signal and suppress the generation of high amplitude spikes. That is, the delay time W is reduced to a value of 0. The spike at the rising edge of the primary square wave of the first laser signal is made to tend to disappear, i.e., the spike peak size H becomes smaller, causing H to approach the size of L.
Since the generation of spikes is related to a sudden increase in pump beam power in the lasing medium in the fiber laser. By controlling the power rise amplitude of the pump beam, the occurrence of spikes can be reduced. The power of the pumping beam in the laser medium is gradually increased, so that excited state particles in the laser medium gradually and slowly accumulate, and the establishment of stable laser oscillation is facilitated.
The principle of the spike generation suppressing method of the present application will be described below.
The invention inputs the second pumping signal to the pumping source to submerge the pulse peak in the rising edge stage of the first laser signal. Wherein the second pump signal is generated by modulating the original pump signal by adding a suppression signal of amplitude (power) a and width (time) K before the original pump signal. As shown in fig. 3A, the waveform of the second pump signal includes a portion 301 and a portion 302, and the second laser signal is generated from the second pump signal. Wherein the second pump signal 301 is partly generated by the suppression signal and the second pump signal 302 is partly generated by the original pump signal. Hereinafter, for convenience of description and correspondence with the drawings, the second pump signal 301 portion is referred to as a suppression waveform 301, and the second pump signal 302 portion is referred to as an original pump waveform 302.
The suppression waveform 301 in the second pump signal first enters the pump source, the pump source drives the pump source to generate a pump beam with corresponding intensity based on the current of the suppression waveform 301, the pump beam enters the laser medium, and the laser medium starts 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 already been entered, and the original pump waveform 302 drives the pump beam generated by the pump source to start entering the laser medium. At this time, a certain level of excited particles are accumulated in the laser medium, and the laser medium starts to generate an amplifying effect, and the spike pulse generated by the suppressing waveform 301 is synchronous 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 smaller than the amplitude (power) of the original pump waveform 302, the peak value of the spike pulse generated by the suppression waveform 301 is smaller than or equal to the amplitude of the second laser signal, which can submerge the spike generated by the suppression waveform 301 in the rising edge of the second laser signal generated by the original pump waveform 302. The laser medium has also responded to completion with the amplitude (power) of the original pump waveform 302 unchanged, 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, without additional compensation. At this time, the laser medium has formed stable gain amplification, and the oscillation output of the fiber laser starts to be stable, so that the laser signal can completely follow the pump source signal to form standard square wave output.
The suppression waveform 301 may be not only a square wave as shown in fig. 3A, but also a ramp waveform as shown in fig. 3B, and also an arc-shaped transition waveform as shown in fig. 3C and 3D. As long as the amplitude (power) a and the width (time) K of the suppression waveform 301 are appropriate, a good suppression effect can be achieved on the spike.
How the invention generates said second pump signal and generates said second laser signal based on said second pump signal will be explained in the following.
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 by the test in advance. And the pulse height in the laser signal is proportional to the power of the initially loaded pump signal, so that the proportional relationship between them can be obtained by testing. To this end, the inventors devised the following test steps:
First, the original pump signal shown in fig. 2A is loaded, and the magnitude V (power) and the width T (time) of the original pump signal are detected or directly acquired. (corresponding to step 601 shown in FIG. 6)
Second, the waveform of the first laser signal generated based on the original pump signal shown in fig. 2A is acquired, and the amplitude H of the spike in the waveform of the first laser signal, the amplitude L when the waveform of the first laser signal is stable, and the delay time W with respect to the original pump signal are detected. (corresponding to step 602 of FIG. 6)
Third, a starting amplitude A of a suppression signal for suppressing the spike is determined based on the magnitude of the detected amplitude V (power) of the original pumping signal, the amplitude H of the spike, and the amplitude L when the first laser signal waveform is stabilized, and a width K of the suppression signal for suppressing the spike is determined based on the delay time W. (corresponding to step 603 shown in FIG. 6)
The width K of the quench signal is the spike delay time W relative to the original pump signal. Calculating a first ratio of the amplitude L of the first laser signal waveform stabilized to the amplitude H of the spike pulseThe first ratio is calculatedMultiplied by the amplitude V of the original pump signal, the result obtained determines the starting amplitude a of the suppression signal. Or calculating a second ratio of the amplitude V of the original pump signal to the amplitude H of the spikeBased on the second ratioAnd the amplitude L at which the first laser signal waveform stabilizes, the resulting result determines the starting amplitude a of the suppression signal, i.e., a= (v×l)/H.
For example, assume that the original pump signal has a width of 50 nanoseconds (ns) and an amplitude of 5 watts (w). The first laser signal has a width of 40ns and an amplitude of 10w. The delay time of the spike pulse is 10ns and the amplitude is 25w. Note that here the magnitude unit of the pumping signal may be a voltage (v).
The width of the quench signal is set equal to the delay time of the spike, i.e. 10ns. A first ratio of the amplitude 10w of the stabilized first laser signal waveform to the amplitude 25w of the spikeMultiplying the first ratio with the amplitude 5w of the original pump signal to obtain a starting amplitude of 2w of the suppression signal, or multiplying the amplitude 5w of the original pump signal with the amplitude 25w of the spike pulse by a second ratioMultiplying the amplitude of the first laser signal when the waveform is stable by 10w, and likewise calculating the initial amplitude of the suppression signal as 2w.
And in a normal working stage, modulating the original pump signal by using the inhibition signal to generate a second pump signal. In this step, there are two methods for generating the second pump signal, which will be explained below. (corresponding to step 604 of FIG. 6)
After the initial amplitude A and the width K of the suppression signal are determined, the suppression signal starts to be generated, wherein the suppression signal rises from the initial amplitude A to the amplitude V of the original pumping signal. The waveform of the suppression signal can be square wave, slope or other curve transition waveform, and a test is carried out to obtain what transition waveform is used specifically, so that a better suppression effect can be obtained.
When the original pump signal is loaded, generation of the quench signal is started, and then the original pump signal is delayed by the width K time of the quench signal. As shown in fig. 4A-4D, the generated suppression signal is added to the delayed original pump signal to obtain the second pump signal.
And secondly, after the initial amplitude A and the width K of the inhibition signal are determined, starting to generate a modulation signal. The width of the modulation signal is set to the suppression signal width K. The result of subtracting the original pump signal amplitude V from the start amplitude a of the suppression signal is determined as the modulation signal start amplitude.
For example, assume that the original pump signal has a width of 50 nanoseconds (ns) and an amplitude of 5 watts (w). The first laser signal has a width of 40ns and an amplitude of 10w. The delay time of the spike pulse is 10ns and the amplitude is 25w. As described above, the width of the calculated suppression signal is 10ns, and the initial amplitude is 2w.
The width of the modulated signal is 10ns, and the result of subtracting the initial amplitude of the suppression signal from the amplitude 5w of the original pump signal is 3w, and the initial amplitude of the modulated signal is 3w.
The modulation signal is synchronously generated when the original pump signal is received. As shown in fig. 4E, the original pump signal is subtracted from the modulated signal to generate a second pump signal. Wherein the width of the steady state pump waveform 302 in the second pump signal generated based on the modulated signal and the original pump signal is the width T of the original pump signal minus the width K of the suppression signal.
If it is desired to generate a second pump signal having a steady state pump waveform 302 that has the same width as the original pump signal, then the width of the original pump signal needs to be widened by the width of the quench signal. That is, the width of the original pump signal after the widening is equal to the width T of the original pump signal plus the width K of the suppression signal. And then subtracting the widened original pump signal from the modulation signal to generate a second pump signal. The second method has the advantage over the first method that no delay circuit is required to delay the original pump signal.
And driving the fiber laser to generate a second laser signal by using the second pump signal. (corresponding to step 605 of FIG. 6)
The above explains by way of two examples how the parameters of the suppression waveform 301 in the second pump signal are obtained by a specific calculation, and how the second pump signal with the suppression signal is generated by a subtraction or addition operation of the original pump signal after being widened or delayed with the modulation signal or the suppression signal generated otherwise, it is also possible to actually obtain the parameters of the suppression waveform 301 by a method of experimental debugging, and to generate the second pump signal with the suppression signal directly by a function signal generator.
If the values of the width and the starting amplitude of the suppression waveform 301 are to be determined, then they are input to the function signal generator, the second pump signal with the suppression signal can be directly obtained without additional operations being required for generation.
Obtaining parameters of the suppression waveform 301 through an experimental debugging method requires estimating values of the width and the initial amplitude of the suppression waveform 301, inputting the estimated values into a waveform function generator to directly generate a waveform of a second pumping signal with a suppression signal, and driving the fiber laser to generate a laser signal by using the second pumping signal. The values of the width and the initial amplitude of the suppression waveform 301 input to the function signal generator are continuously changed, and the relative positions and the suppression conditions of the spike pulse and the square wave in the laser signal waveform output by the fiber laser are observed, so that the change is not stopped until the laser signal output by the fiber laser is observed to be consistent with the second laser signal. The values described in the function signal generator are then determined values of the desired width and starting amplitude of the suppression waveform 301.
During observation, the width of the suppression waveform 301 is gradually increased if the time at which the spike occurs leads the rising edge of the square wave, and the width of the suppression waveform 301 is decreased if the spike lags the rising edge of the square wave. If the amplitude of the spike is higher than the amplitude of the square wave, the starting amplitude of the suppression waveform 301 is reduced.
The specific ways in which the second pump signals are generated are set forth above depends on the actual needs of the user and is not limited to the specific embodiments described herein.
Exemplary apparatus
Having described the method of an exemplary embodiment of the present invention, next, an exemplary embodiment of the present invention may be implemented by the following means with reference to fig. 5. As shown in fig. 5, the device comprises 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 modes are as follows:
the original pump signal generating means 501 are arranged to generate an original pump signal. In the test phase, line a shown in fig. 5 is open and line b is closed, and the original pump signal generating means 501 passes the generated original pump signal directly to the fiber laser 503 via line a. The amplitude and width of the original pump signal are obtained simultaneously and fed back to the computing means 505.
After the optical fiber laser 503 receives the original pump signal transmitted from the line a, the original pump signal drives a pump source in the optical fiber laser 503 to generate a corresponding pump beam, the pump beam is coupled into an optical cavity through an optical coupler in the optical fiber laser 503, and a laser medium in the optical cavity starts gain amplification, and outputs a first laser signal.
The laser signal detection device 504 is connected to the output end of the fiber laser 503, acquires the waveform of the first laser signal generated by driving the fiber laser 503 by the pump light generated based on the original pump signal, detects the amplitude of the spike pulse in the waveform of the first laser signal, the amplitude when the waveform of the first laser signal is stable, and the delay time relative to the original pump signal, and feeds back the detected pulse to the calculation device 505.
After the operation is completed, the normal working stage is entered. The original pump signal generating means 501 closes the line a and no longer delivers the original pump signal to the fiber laser 503, opens the line b and delivers the original pump signal to the second pump signal generating means.
The calculating means 505 receives the amplitude and width of the original pump signal transmitted from the original pump signal generating means 501, and receives the amplitude of the spike pulse in the first laser signal waveform transmitted from the laser signal detecting means 504, the amplitude when the first laser signal waveform is stable, and the delay time with respect to the original pump signal. The width and the starting amplitude of the modulated signal and the width and the starting amplitude of the suppressed signal are calculated based on the received data.
The calculating means 505 comprises a suppression signal width determining means 506, a suppression signal amplitude determining means 507.
The suppression signal width determining means 506 is used for determining the width of the suppression signal. Which will 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 generating means 502.
The suppression signal amplitude determining means 507 are arranged for determining a starting amplitude of the suppression signal. The first ratio of the amplitude of the first laser signal waveform stabilization to 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 quench signal and the starting amplitude of the quench signal is fed back to the second pump signal generating means 502, or the second ratio of 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 waveform stabilization to determine the starting amplitude of the quench signal and the starting amplitude of the quench signal is fed back to the second pump signal generating means 502.
The second pump signal generating means 502 modulates the original pump signal with the suppression signal to generate a second pump signal. The second pump signal generating device 502 comprises a signal generating module 511, an original pump signal modulating module 510, a combining module 512.
The original pump signal modulation module 510 receives the original pump signal delivered by the original pump signal generation means 501 via line b, and also receives the width of the suppression signal delivered by the suppression signal width determination means 506. The original pump signal modulation module 510 performs a delay suppression signal width on the original pump signal. For example, the width of the quench signal is 10ns, then the original pump signal is delayed by 10ns. The delayed original pump signal is sent to a combining block 512.
The signal generating module 511 receives the width of the suppression signal delivered from the suppression signal width determining means 506 and receives the starting amplitude of the suppression signal delivered from the suppression signal amplitude determining means 507. Based on these two parameters, a quench signal is then generated when the original pump signal is received by the original pump signal modulation module 510, while the quench signal is sent to the combining module 512.
The combining module 512 adds the received suppression signal to the delayed original pump signal to generate the second pump signal.
The computing means 505 further comprises modulation signal width determining means 508, modulation signal amplitude determining means 509.
The modulation signal width determining means 508 is for determining the width of the modulation signal. Which will 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 means 502.
The modulation signal amplitude determining means 509 is configured to determine a result of subtracting the initial amplitude of the suppression signal from the amplitude of the original pump signal as a modulation signal initial amplitude, and feed back the initial amplitude of the modulation signal to the second pump signal generating means 502.
The original pump signal modulation module 510 receives the original pump signal delivered through line b from the original pump signal generation device 501 and sends the original pump signal to the combining module 512.
The signal generating module 511 receives the width of the modulated signal delivered from the modulated signal width determining means 508 and receives the starting amplitude of the modulated signal delivered from the modulated signal amplitude determining means 509. Based on these two parameters, a modulated signal is then generated when the original pump signal is received by the original pump signal modulation module 510, while the modulated signal is sent to the combining module 512.
The combining module 512 subtracts the received modulated signal from the original pump signal to generate the second pump signal.
The width of the original pump waveform 302 in the second pump signal generated in the combining module 512 based on the original pump signal output by the original pump signal modulating module 510 and the modulated signal output by the signal generating module 511 is the width of the original pump signal minus the width of the suppression signal. If the width of the original pump waveform 302 of the second pump signal output by the combining module is the width of the original pump signal, the combining module 512, the signal generating module 511 and the original pump signal modulating module 510 in the second pump signal generating device 502 are made to perform the following operations:
The original pump signal modulation module 510 receives the original pump signal delivered by the original pump signal generation means 501 via line b, and also receives the width of the suppression signal delivered by the suppression signal width determination means 506. The original pump signal modulation module 510 widens the width of the suppression signal for the width of the original pump signal. For example, the width of the quench 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 combining module 512.
The signal generating module 511 receives the width of the modulated signal delivered from the modulated signal width determining means 508 and receives the starting amplitude of the modulated signal delivered from the modulated signal amplitude determining means 509. Based on these two parameters, a modulated signal is then generated when the original pump signal is received by the original pump signal modulation module 510, while the modulated signal is sent to the combining module 512.
The combining module 512 subtracts the received modulated signal from the widened original pump signal to generate the second pump signal.
The fiber laser 503 generates a second laser signal by driving the pump light with the second pump signal.
The present invention is not limited to the above-described connection method, and suitable devices and connection methods may be selected according to specific applications and device requirements. In practice, some tuning and optimization may be required to ensure proper operation of the device and to obtain the desired pump signal characteristics.
The invention is not limited to the specific embodiments disclosed nor does it imply that features in these aspects are not combinable to benefit from this division, which is for convenience of presentation only. The invention is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.
The invention provides:
1. a method of suppressing a fiber laser spike, comprising:
Generating an original pumping signal and acquiring the amplitude and the width of the original pumping signal;
determining preset parameters based on a first laser signal generated by the original pump signal;
Determining the width and the initial amplitude of a suppression signal for suppressing spike pulses in the first laser signal waveform based on the preset parameters;
modulating the original pump signal by using the suppression signal to generate a second pump signal;
and driving the fiber laser to generate a second laser signal by using the second pump signal.
2. The method of claim 1, wherein the determining the preset parameters based on the first laser signal generated from the original pump signal further comprises the steps of:
acquiring the waveform of the first laser signal, and detecting the amplitude of spike pulse in the waveform of the first laser signal, the amplitude of the waveform of the first laser signal when stable and the delay time relative to the original pumping signal;
and determining the detected amplitude of the original pumping signal, the amplitude of the first laser signal when the waveform is stable, the delay time and the amplitude of the spike pulse as the preset parameters.
3. The method of claim 1, wherein said determining the width and starting amplitude of the suppression signal for suppressing spikes based on said preset parameters further comprises the steps of:
calculating a first ratio of the amplitude of the first laser signal waveform at stabilization to the amplitude of the spike, determining a starting amplitude of the quench signal based on the first ratio and the amplitude of the original pump signal, or
Calculating a second ratio of the amplitude of the original pump signal to the amplitude of the spike pulse, determining a starting amplitude of the quench 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 of claim 3, wherein said determining the starting amplitude of the suppression signal based on the first ratio and the amplitude of the original pump signal further comprises the steps of:
Multiplying the first ratio by the amplitude of the original pump signal to determine the initial amplitude of the suppression signal, or
The determining the starting amplitude of the suppression signal based on the second ratio and the amplitude of the first laser signal waveform when stable further comprises the steps of:
multiplying the second ratio by the amplitude of the first laser signal when the waveform is stable determines the starting amplitude of the quench signal.
5. The method of claim 1, wherein the modulating the original pump signal with the suppression signal, generating a second pump signal further comprises:
a waveform of a second pump signal is then generated by adding the suppression signal to the front edge of the original pump signal.
6. The method of claim 5, wherein said generating a waveform of a second pump signal immediately following adding said suppression signal to a leading edge of said original pump signal further comprises the steps of:
the quench signal rises from the starting amplitude to the amplitude of the original pump signal.
7. The method of any of claims 1-6, wherein the modulating the original pump signal with the suppression signal, generating a second pump signal further comprises:
Generating the quench signal upon receipt of the original pump signal;
Delaying the original pump signal by the width of the inhibit signal;
And adding the generated inhibition signal and the delayed original pump signal to obtain the second pump signal.
8. The method of claim 1, wherein the modulating the original pump signal with the suppression signal, generating a second pump signal further comprises:
determining the width of the suppression signal as the width of the modulation signal;
Determining the result of subtracting the initial amplitude of the suppression signal from the amplitude of the original pump signal as the initial amplitude of the modulation signal;
generating the modulation signal upon receiving the original pump signal;
And subtracting the original pump signal from the modulation signal to generate a second pump signal.
9. The method of claim 1, wherein the modulating the original pump signal with the suppression signal, generating a second pump signal further comprises:
determining the width of the suppression signal as the width of the modulation signal;
Determining the result of subtracting the initial amplitude of the suppression signal from the amplitude of the original pump signal as the initial amplitude of the modulation signal;
Widening the width of the original pump signal by the width of the suppression signal;
and subtracting the widened original pump signal from the modulation signal to generate a second pump signal.
10. An apparatus for suppressing a fiber laser spike, comprising:
The device comprises 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 for generating an original pump signal, obtaining the amplitude and the width of the original pump signal and feeding the original pump signal back to the computing device;
The laser signal detection device determines preset parameters based on a first laser signal generated by the original pumping signal, and feeds back the preset parameters to the calculation device;
The computing device determines the width and the initial amplitude of the suppression signal for suppressing the spike based on the preset parameters;
The second pump signal generating device modulates the original pump signal by using the suppression signal to generate a second pump signal;
the fiber laser generates a second laser signal by using the second pump signal to drive and generate pump light.
11. The apparatus of claim 10, the laser signal detection device further comprising:
acquiring a waveform of a first laser signal generated based on the original pump signal, and detecting the amplitude of spike pulses in the waveform of the first laser signal, the amplitude when the waveform of the first laser signal is stable and the delay time relative to the original pump signal;
and determining the detected amplitude of the original pumping signal, the amplitude of the first laser signal when the waveform is stable, the delay time and the amplitude of the spike pulse as the preset parameters.
12. The apparatus of claim 10, the computing device further comprising:
a suppression signal amplitude determining means for:
calculating a first ratio of the amplitude of the first laser signal waveform stabilized to the amplitude of the spike pulse, multiplying the first ratio by the amplitude of the original pump signal to determine the initial amplitude of the suppression signal, and feeding back to the second pump signal generating device, or
Calculating a second ratio of the amplitude of the original pumping signal to the amplitude of the spike pulse, multiplying the second ratio by the amplitude of the first laser signal when the waveform of the first laser signal is stable to determine the initial amplitude of the suppression signal, and feeding back to a second pumping signal generating device, and
And a suppression signal width determining means for determining the delay time as the width of the suppression signal and feeding back to the second pump signal generating means.
13. The apparatus of claim 12, wherein the second pump signal generating means further comprises a signal generating module, an original pump signal modulating module, a combining module;
the signal generation module generates a suppression signal when the original pump signal is received;
The original pump signal modulation module is used for delaying an original pump signal;
the combining module is used for adding the suppression signal and the delayed original pump signal to generate the second pump signal.
14. The apparatus of claim 13, wherein the original pump signal modulation module is to
The original pump signal is delayed by the width of the quench signal.
15. The apparatus of claim 12, the computing device further comprising:
Modulation signal width determining means for determining the suppression signal width as the width of the modulation signal and feeding back to the second pump signal generating means;
And the modulation signal amplitude determining device is used for determining the result of subtracting the initial amplitude of the suppression signal from the amplitude of the original pump signal as the initial amplitude of the modulation signal and feeding back the initial amplitude of the modulation signal to the second pump signal generating device.
16. The apparatus of claim 15, wherein the second pump signal generating means further comprises a signal generating module and a combining module;
The signal generation module generates the modulation signal when receiving the original pump signal;
The combining module is used for subtracting the modulating signal from the original pumping signal to generate the second pumping signal.
17. The apparatus of claim 15, wherein the second pump signal generating means further comprises an original pump signal modulating module for widening the width of the original pump signal by the suppression signal width;
the combining module is used for subtracting the modulated signal from the widened original pump signal to generate the second pump signal.