CN115360576B - A multi-pulse laser - Google Patents

Abstract

The present disclosure provides a multipulse laser. The controller obtains the laser intensity in the laser resonant cavity through the optical detector, and the controller controls the Q-switching module to output laser outwards in a multi-pulse mode through outputting a control instruction, so that the multi-pulse can be adjustable in peak value, pulse width, pulse interval, period and the like; the controller controls the adjustable pumping source to adjust the pumping light intensity through adjusting the control instruction, so that the Q-switched module can output the multi-pulse laser outwards in the next pumping period immediately adjacent to the current pumping period. Thereby realizing the adjustable and controllable multi-pulse laser.

Description

A multi-pulse laser

technical field

The present disclosure relates to the field of laser technology, in particular, to a multi-pulse laser.

Background technique

With the development of laser technology, double-pulse solid-state lasers have achieved broad application prospects in military, scientific research, laser processing and other fields. Among them, the dynamically adjustable double-pulse solid-state laser is an important direction of development.

At present, due to the control obstacles of double-pulse solid-state lasers, good double-pulse laser signals cannot be obtained, resulting in unsatisfactory application results. Therefore, how to control the output of double-pulse lasers has become the key to the development of this field.

Therefore, the present disclosure provides a multi-pulse laser to solve one of the above technical problems.

Contents of the invention

The purpose of the present disclosure is to provide a multi-pulse laser capable of solving at least one of the above-mentioned technical problems. The specific plan is as follows:

According to a specific implementation manner of the present disclosure, in a first aspect, the present disclosure provides a multi-pulse laser, including:

A photodetector and a controller, and at least one adjustable pump source, a laser resonator, a laser crystal, and a Q-switching module arranged in sequence along the optical path direction, wherein the Q-switching module and the laser crystal are arranged in the laser resonator Inside;

The adjustable pumping source is configured to inject pumping light into the laser resonant cavity along the direction of the optical path, and the pumping light intensity of the pumping light can be adjusted through the adjustment control command of the controller;

The laser resonant cavity is a Z-shaped cavity, including an input mirror, a first reflective mirror, a second reflective mirror and an output mirror sequentially arranged along the optical path, and the laser crystal is located between the input mirror and the first reflective mirror , the Q-switching module is located between the second mirror and the output mirror;

The Q-switching module is configured to make the laser resonator output laser light in a multi-pulse manner in each pumping cycle under the control of the output control instruction of the controller;

The photodetector is arranged adjacent to the second reflector, and is configured to receive a detection signal output by the second reflector, so as to obtain the laser light intensity in the laser resonator;

The controller is connected to the adjustable pumping source, the Q-switching module and the photodetector respectively, and is configured to generate corresponding pumping based on the preset multi-pulse characteristic information of each pumping cycle. A periodic output control command; in each pumping cycle, an adjustment control command is generated based on the detected laser light intensity and the preset pulse loss light intensity in the next pumping cycle immediately adjacent to the current pumping cycle; in response to the adjustment The control instruction controls the adjustable pump source to adjust the intensity of the pump light, so that the Q-switching module controls the laser resonator to output multi-pulse lasers based on the output control instruction corresponding to the pumping cycle.

Optionally, the multi-pulse laser includes multiple pulse lasers within one pumping cycle;

The pumping period includes at least a pulse time period of each pulsed laser;

The preset pulse loss light intensity includes the sum of the preset loss light intensity of each pulse laser in the next pumping cycle immediately adjacent to the current pumping cycle;

The controller is configured to generate adjustment control instructions based on the detected laser light intensity and the preset pulse loss light intensity in the next pumping cycle immediately adjacent to the current pumping cycle in each pumping cycle, including:

Obtaining the current laser light intensity in the laser resonator, the current detection time point and the start time point of the next pumping cycle immediately adjacent to the current pumping cycle;

obtaining a total loss light intensity based on the preset pulse loss light intensity and the preset inherent loss light intensity;

Obtaining the light intensity to be supplemented based on the total lost light intensity and the current laser light intensity;

Obtaining a transition time period of the laser in the laser resonator based on the start time point and the current detection time point;

Obtaining a required transition rate based on the light intensity to be supplemented and the transition time period;

Obtaining the required pump light intensity of the adjustable pump source based on the required transition rate and the transition model of the laser resonator;

The adjustment control instruction is generated based on the required pump light intensity.

Optionally, the adjustable pumping source includes a first adjustable pumping source and a second adjustable pumping source respectively connected to the controller point electrical signal;

The controller is configured to generate the adjustment control instruction based on the required pump light intensity, comprising:

obtaining a light intensity ratio based on a first maximum light intensity of the first adjustable pump source and a second maximum light intensity of the second adjustable pump source;

Allocate the required pump light intensity based on the light intensity ratio to obtain the first required pump light intensity of the first adjustable pump source and the required pump light intensity of the second adjustable pump source. The second required pump light intensity;

generating a first adjustment control instruction for the first adjustable pump source based on the first required pump light intensity, and,

A second adjustment control command for the second adjustable pump source is generated based on the second required pump light intensity.

Optionally, the controller is configured to generate an output control instruction corresponding to the pumping cycle for the preset multi-pulse feature information based on each pumping cycle, including:

A peak value control instruction corresponding to a corresponding pulse in each pumping cycle is generated based on a preset peak value of each pulse in each pumping cycle.

Optionally, the controller is configured to generate an output control instruction corresponding to the pumping cycle for the preset multi-pulse feature information based on each pumping cycle, including:

A pulse width control instruction corresponding to a corresponding pulse in each pumping cycle is generated based on a preset pulse width value of each pulse in each pumping cycle.

Optionally, the controller is configured to generate an output control instruction corresponding to the pumping cycle for the preset multi-pulse feature information based on each pumping cycle, including:

A pulse interval control instruction corresponding to two adjacent pulses in each pumping cycle is generated based on a preset pulse interval value between two adjacent pulses in each pumping cycle.

Optionally, the controller is configured to generate an output control instruction corresponding to the pumping cycle for the preset multi-pulse feature information based on each pumping cycle, including:

A cycle control instruction corresponding to the pumping cycle is generated based on the preset cycle value of each pumping cycle.

Optionally, the total loss ε satisfies the following relationship:

ε=Z+ξ(t)

Z is the inherent loss, ξ(t) is the time-dependent loss introduced by the Q switch, and ξ(t) satisfies the following relationship:

Among them, Lq is the basic loss factor of Q-switching, T _a is a pumping cycle

The duration of high loss in a pump cycle; T _b is the duration of low loss in a pumping cycle

The time, k is the high and low loss proportional coefficient, and t is the time.

Compared with the prior art, the above solutions of the embodiments of the present disclosure have at least the following beneficial effects:

The present disclosure provides a multi-pulse laser. Wherein the controller obtains the laser light intensity in the laser resonator through a photodetector, and the controller controls the Q-switching module to output the laser in a multi-pulse manner through an output control command, and can realize multi-pulse at the peak , pulse width, pulse interval and/or cycle, etc. are adjustable; the controller controls the adjustable pump source to adjust the intensity of the pump light by adjusting the control command, so that the Q-switching module can be close to the current pumping cycle In the next pumping cycle, the multi-pulse laser is output to the outside. Thus, the adjustable and controllable multi-pulse laser is realized.

Description of drawings

FIG. 1 shows a schematic diagram of a cavity of a laser resonator according to an embodiment of the present disclosure;

FIG. 2 shows a graph of Q-switched loss versus time for a double-pulse laser according to an embodiment of the present disclosure;

Explanation of reference signs

21-laser resonator, 22-adjustable pump source, 23-photodetector, 24-Q-switching module, 25-controller;

211-input mirror, 212-first reflector, 213-second reflector, 214-output mirror, 215-laser crystal;

221 - the first adjustable pumping source, 222 - the second adjustable pumping source.

Detailed ways

In order to make the purpose, technical solutions and advantages of the present disclosure clearer, the present disclosure will be further described in detail below in conjunction with the accompanying drawings. Apparently, the described embodiments are only some of the embodiments of the present disclosure, not all of them. Based on the embodiments in the present disclosure, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of the present disclosure.

Terms used in the embodiments of the present disclosure are for the purpose of describing specific embodiments only, and are not intended to limit the present disclosure. The singular forms "a", "said" and "the" used in the embodiments of this disclosure and the appended claims are also intended to include plural forms, unless the context clearly indicates otherwise, "a plurality" Generally contain at least two.

It should be understood that the term "and/or" used herein is only an association relationship describing associated objects, which means that there may be three relationships, for example, A and/or B, which may mean that A exists alone, and A and B exist simultaneously. B, there are three situations of B alone. In addition, the character "/" in this article generally indicates that the contextual objects are an "or" relationship.

It should be understood that although the terms first, second, third, etc. may be used for description in the embodiments of the present disclosure, these descriptions should not be limited to these terms. These terms are used only to differentiate the descriptions. For example, without departing from the scope of the embodiments of the present disclosure, the first may also be referred to as the second, and similarly, the second may also be referred to as the first.

Depending on the context, the words "if", "if" as used herein may be interpreted as "at" or "when" or "in response to determining" or "in response to detecting". Similarly, depending on the context, the phrases "if determined" or "if detected (the stated condition or event)" could be interpreted as "when determined" or "in response to the determination" or "when detected (the stated condition or event) )" or "in response to detection of (a stated condition or event)".

It should also be noted that the term "comprises", "comprises" or any other variation thereof is intended to cover a non-exclusive inclusion such that an article or arrangement comprising a list of elements includes not only those elements but also includes items not expressly listed. other elements of the product, or elements inherent in the product or device. Without further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in an article or device comprising said element.

In particular, it should be noted that if the symbols and/or numbers in the description are not marked in the description of the drawings, they are not reference signs.

Optional embodiments of the present disclosure will be described in detail below in conjunction with the accompanying drawings.

Example 1

The embodiment provided in the present disclosure is an embodiment of a multi-pulse laser.

Embodiments of the present disclosure will be described in detail below in conjunction with the accompanying drawings.

As shown in FIG. 1 , an embodiment of the present disclosure provides a multi-pulse laser, including: a photodetector and a controller, and at least one adjustable pump source, a laser resonator, a laser crystal, and a tuning A Q module, wherein the Q-switching module and the laser crystal are arranged in the laser resonant cavity.

The laser resonant cavity is an essential part of the laser, and the laser resonant cavity is used to make the pumping light injected into the cavity generate laser light during oscillation, and emit the laser light out of the cavity.

A laser crystal and at least two mirrors are usually arranged in the laser resonator, so that the pump light injected into the cavity oscillates repeatedly between at least two mirrors, so that the laser crystal placed on the optical path realizes particle Laser light is generated after the number is reversed.

The function of the resonant cavity is to select the light with a certain frequency and the same direction as the most preferential amplification, and suppress the light of other frequencies and directions. All photons that do not move along the optical path of the laser resonator escape out of the cavity quickly and no longer contact the laser crystal. The photons moving along the optical path will continue to move forward in the cavity, and will continue to run back and forth through the reflection of the mirror to generate oscillations. During operation, they will continue to meet the stimulated particles in the laser crystal to generate stimulated radiation, and the photons running along the optical path will continue to increase. , forming a strong beam with the same propagation direction, the same frequency and phase in the cavity, that is, laser light. In order to lead the laser light out of the cavity, a reflector can be made semi-transmissive, the transmissive part becomes usable laser light, and the reflective part stays in the cavity to continue multiplying photons. The role of the laser resonator: firstly, to provide feedback energy, and secondly, to select the direction and frequency of the light wave. The above-mentioned process of using light to raise electrons from a lower energy level in an atom or molecule to a higher energy level is called pumping. Lasers achieve stimulated radiation amplification by pumping laser crystals.

The optical path is also the path through which photons repeatedly oscillate.

As shown in FIG. 1 , the laser resonant cavity described in the embodiment of the present disclosure is a Z-shaped cavity, and the optical path in the Z-shaped cavity is configured in a zigzag shape to facilitate the detection of the optical detector. The laser resonant cavity includes an input mirror, a first reflective mirror, a second reflective mirror and an output mirror sequentially arranged along the optical path. Both the input mirror and the output mirror are configured as semi-mirrors. The pump light can enter from the input mirror along the optical path, and when the photon returns, the input mirror can also reflect the photon. The output mirror can reflect photons, and when the Q-switching module is turned on, it can also emit laser light to the outside. Both the first reflection mirror and the second reflection can reflect photons on the light path. For example, the first reflector is set at an angle of 45 degrees to the input mirror; the second reflector is set parallel to the first reflector; and the second reflector is set at an angle of 45 degrees to the output mirror; such setting is convenient for adjustment and installation. The laser crystal is located between the input mirror and the first reflection mirror, and the Q-switching module is located between the second reflection mirror and the output mirror.

The adjustable pumping source is set behind a reflector with partial projection function. The adjustable pumping source is configured to inject pumping light into the laser resonant cavity along the direction of the optical path, and the pumping light intensity of the pumping light can be adjusted through an adjustment control command of the controller. In order to meet the needs of multi-pulse lasers, one high-power adjustable pump source can be set, and multiple adjustable pump sources can also be set. For example, as shown in Figure 1, the at least one adjustable pumping source includes a first adjustable pumping source and a second adjustable pumping source respectively connected to the controller signal; the first adjustable pumping The pump light emitted by the pump source is incident from the input mirror and directed to the first reflector; the pump light emitted from the second adjustable pump source is entered by the first reflector and directed to the first reflector. The input mirror, at this time, the first reflector is also a half mirror, the second pump light can enter from the first reflector along the optical path, and when the photon returns, it can reflect the photon. Compared with a single adjustable pump source, the use of multiple adjustable pump sources can flexibly control the incident amount of pump light to achieve various requirements for outputting multi-pulse lasers.

In order to enable the laser resonator to emit multi-pulse laser light, an embodiment of the present disclosure provides a Q-switching module.

The Q-switching module is configured to make the laser resonator output laser light in a multi-pulse manner in each pumping period under the control of an output control instruction of the controller.

For example, as shown in Figure 2, the 0-t3 time period is a pumping cycle. If the laser resonator emits a double-pulse laser, the controller passes through the Q-switching module during the 0-t1 time period within a pumping cycle. The first pulsed laser is output to the outside, and the controller outputs the second pulsed laser to the outside through the Q-switching module within the time period t1-t2 in the same pumping cycle.

In order to be able to output a multi-pulse laser that meets the requirements in each pumping cycle, it is necessary to realize adjustable peak value, adjustable pulse width, adjustable pulse interval and/or adjustable period of the pulsed laser. To this end, the present application provides photodetectors.

The photodetector is disposed adjacent to the second reflector and is configured to receive a detection signal output by the second reflector to obtain the laser light intensity in the laser resonant cavity. For example, as shown in Figure 2, the 0-t3 time period is a pumping cycle, the photodetector detects the laser light intensity of the first pulse laser at time 0 and the laser light intensity at time t1, and the controller can determine The first pulsed laser consumes a lot of energy and is a high-loss laser; the light detector detects the laser light intensity of the second pulsed laser at the time point t1 and the laser light intensity at the time point t2, and the controller can determine the second A pulsed laser consumes a small amount of energy and is a low-loss laser; the light detector detects no loss of laser light intensity during the time period t2-t3, and the controller can determine that there is no pulsed laser output during this time period.

The controller is connected to the adjustable pumping source, the Q-switching module and the photodetector respectively, and is configured to generate corresponding pumping based on the preset multi-pulse characteristic information of each pumping cycle. A periodic output control command; in each pumping cycle, an adjustment control command is generated based on the detected laser light intensity and the preset pulse loss light intensity in the next pumping cycle immediately adjacent to the current pumping cycle; in response to the adjustment The control instruction controls the adjustable pump source to adjust the intensity of the pump light, so that the Q-switching module controls the laser resonator to output multi-pulse lasers based on the output control instruction corresponding to the pumping cycle.

In the process of controlling the laser resonator to output multi-pulse laser, the controller controls the Q-switching module to output laser in a multi-pulse manner through the output control command, and controls the adjustment of the adjustable pump source through the adjustment control command. The intensity of the pumping light is such that the Q-switching module controls the laser resonator to output multi-pulse lasers based on the output control instruction corresponding to the pumping cycle.

The embodiments of the present disclosure can realize adjustable peak value, adjustable pulse width, adjustable pulse interval and/or adjustable cycle of the pulsed laser through the preset multi-pulse feature of each pumping cycle. The same preset multi-pulse feature can be used for multiple consecutive adjacent pumping cycles, or the preset multi-pulse feature of each adjacent pumping cycle can be different. Based on the photodetector 23, the current pulse characteristic information of the laser in the resonator, such as peak power, pulse width, frequency, etc., can be obtained. A control command is generated based on the current pulse feature information and preset pulse feature information for control. For example, adjust the peak power based on the current peak power and the expected peak power, adjust the pulse width based on the current pulse width and the expected pulse width, and adjust the pulse interval based on the current pulse interval and the expected pulse interval .

In some specific embodiments, the controller is configured to generate the output control instruction corresponding to the pumping cycle based on the preset multi-pulse feature information of each pumping cycle, including: based on each pulse in each pumping cycle The preset peak value of is generated corresponding to the peak value control command of the corresponding pulse in the pumping cycle.

In this specific embodiment, the preset multi-pulse feature information includes a preset peak value of each pulse in each pumping cycle. The output control instruction includes a peak value control instruction for each pulse in each pumping cycle. The controller controls the Q-switching module to output the laser of each pulse based on the peak value control instruction of each pulse in each pumping cycle.

In some other specific embodiments, the controller is configured to generate the output control instruction corresponding to the pumping cycle based on the preset multi-pulse feature information of each pumping cycle, including: based on each of the pumping cycles The preset pulse width value of the pulse generates a pulse width control command corresponding to the corresponding pulse in the pumping cycle.

In this specific embodiment, the preset multi-pulse characteristic information includes a preset pulse width value of each pulse in each pumping cycle. The output control instruction includes a pulse width control instruction for each pulse in each pumping cycle. The controller controls the Q-switching module to output the laser light of each pulse in each pumping cycle based on the pulse width control instruction of each pulse.

In some other specific embodiments, the controller is configured to generate the output control instruction corresponding to the pumping cycle based on the preset multi-pulse feature information of each pumping cycle, including: based on the adjacent pulses in each pumping cycle The preset pulse interval value of two pulses generates a pulse interval control instruction corresponding to two adjacent pulses in the pumping cycle.

In this specific embodiment, the preset multi-pulse characteristic information includes a preset pulse interval value of each pulse in each pumping cycle. The output control instruction includes a pulse interval control instruction for each pulse in each pumping cycle. The controller controls the Q-switching module to output the laser light of each pulse in each pumping cycle based on the pulse interval control instruction of each pulse.

In other specific embodiments, the controller is configured to generate an output control instruction corresponding to the pumping cycle based on the preset multi-pulse feature information of each pumping cycle, including: The period value generates a period control instruction corresponding to the pump period.

In this specific embodiment, the preset multi-pulse feature information includes a preset cycle value of each pulse in each pumping cycle. The output control instructions include period control instructions for each pulse in each pumping cycle. The controller controls the Q-switching module to output the laser light of each pulse in each pumping cycle based on the cycle control instruction of each pulse.

Certainly, when adjusting the output control command of the multi-pulse laser, at least one of the peak value control command, the pulse width control command, the pulse interval control command and the period control command can be adjusted.

In some embodiments, the multi-pulse laser light includes multiple pulse laser light within one pumping cycle. For example, a double-pulse laser within one pumping cycle.

The pumping period includes at least a pulse time period of each pulse laser. For example, as shown in Figure 2, the 0-t3 time period is a pumping cycle, and the laser resonator emits a double-pulse laser. During the 0-t1 time period in a pumping cycle, the controller sends out The first pulsed laser is output, and the controller outputs the second pulsed laser through the Q-switching module within the t1-t2 period of the same pumping cycle.

The preset pulse loss light intensity includes the sum of the preset loss light intensity of each pulse laser in the next pumping cycle immediately adjacent to the current pumping cycle. For example, as shown in Figure 2, the current pumping cycle is the 0-t3 time period, then the next pumping cycle next to the current pumping cycle is the t3-t6 time period; the preset loss light intensity of the first pulse laser is v1=10W/cm ² , the preset loss intensity of the second pulse laser is v2=5W/cm ² , then the preset pulse loss intensity is v1+v2=10W/cm ² +5W/cm ² =15W/ cm ² .

Correspondingly, the controller is configured to generate adjustment control instructions based on the detected laser light intensity and the preset pulse loss light intensity in the next pumping cycle immediately adjacent to the current pumping cycle in each pumping cycle, including:

Step S101, acquiring the current laser light intensity in the laser cavity, the current detection time point and the start time point of the next pumping cycle immediately adjacent to the current pumping cycle.

For example, as shown in Figure 2, t1=1s, t2=2s, t3=3s, t4=4s, t5=5s, t6=6s, the current pumping period is 0-3s, and the current detection time point is 0.5s. The current laser light intensity obtained at the current detection time point is 10W/cm ² , the next pumping cycle next to the current pumping cycle is 3-5s, and the start time of the next pumping cycle is also the end time of the current pumping cycle Point 3s.

Step S102, obtaining the total light loss intensity based on the preset pulse loss light intensity and the preset intrinsic light loss intensity in the next pumping cycle immediately adjacent to the current pumping cycle.

The preset intrinsic loss light intensity includes the loss of the laser intensity dissipated when the laser is scattered and back and forth in the next pumping cycle immediately adjacent to the current pumping cycle. The preset inherent loss light intensity is positively correlated with the length of the pumping cycle and the length of the optical path in the laser resonator. The larger the length of the pumping cycle, the greater the preset inherent loss light intensity; the longer the length of the optical path, the preset inherent loss. The loss of light intensity is also greater. The same length of the pumping cycle, and the same length of the optical path, the preset inherent loss of light intensity is the same.

For example, as shown in Figure 2, the preset pulse loss light in the next pumping cycle is 15W/cm ² , the preset intrinsic light loss intensity is 0.5W/cm ² , and the total loss light intensity is 15.5W/cm ² ; Since the length of the current pumping cycle is the same as the length of the next pumping cycle immediately adjacent to the current pumping cycle, the preset intrinsic loss light intensity of the two pumping cycles is 0.5 W/cm ² .

We can express it through the rate equation as:

Equation (1) describes the relationship of the number density of inversion particles in the resonant cavity with time.

Equation (2) describes the relationship between the number density of photons in the laser medium and time, and Equation (3) describes the relationship between the total loss and time.

In the formula, ε is the total loss, as shown in formula (4).

ε=Z+ξ(t) (4)

Z is the sum of non-time-related losses such as light scattering and round-trip light dissipation, that is, the inherent loss, and ξ(t) is the time-dependent loss introduced by the Q switch, as shown in formula (5).

R _P - pumping rate;

σ _e —effective emission cross section;

τ——Laser upper level spontaneous emission lifetime;

n——Refractive index of laser working material;

f _u ——Boltzmann factor of the upper energy level;

f _l ——Boltzmann factor of the lower energy level;

——⁵I₇上能级未泵浦时的粒子数密度；

——the particle number density when the energy level above ⁵ I ₇ is not pumped;

Φ——the total number of photons in the resonator;

ΔN——reverse particle number density;

τ _c ——photon lifetime in the cavity;

t _r ——the round-trip time of photons in the cavity, t _r =2l'/c, l' is the cavity length of the resonator;

t _c —the average lifetime of photons in the cavity;

ε——total loss;

Z——is the sum of loss not related to time, such as light scattering and round-trip light dissipation;

L _q ——Basic loss factor of Q-switching;

k——The introduced high and low loss proportional coefficient is U _a /U _b (U _a and U _b represent the voltage under high loss and low loss);

T _a - duration of high loss in one pumping cycle;

T _b - the duration of low loss in one pumping cycle.

Step S103, obtaining the light intensity to be supplemented based on the total lost light intensity and the current laser light intensity.

The embodiment of the present disclosure dynamically detects the current laser light intensity in the current pumping cycle in real time, and calculates the light intensity to be supplemented in the next pumping cycle immediately adjacent to the current pumping cycle through the current laser light intensity in real time. For example, continuing the above example, the current pumping cycle is 0-3s, the next pumping cycle next to the current pumping cycle is 3-5s, and when the current detection time point is 0.5s, the detected current laser light intensity is 10.3W /cm ² , the total loss light intensity in the next pumping cycle immediately adjacent to the current pumping cycle is 15.5W/cm ² , then the light intensity to be supplemented = 15.5W/cm ² -10.3W/cm ² = 5.2W/cm ² ; when the current detection time point is 1.5s, the detected current laser light intensity is 4.8W/cm ² , and the total loss light intensity in the next pumping cycle immediately adjacent to the current pumping cycle is 15.5W/cm ² , then Light intensity to be supplemented = 15.5W/cm ² -4.8W/cm ² = 10.7W/cm ² .

Step S104, based on the start time point of the next pumping cycle immediately adjacent to the current pumping cycle and the current detection time point, the transition time period of the laser light in the laser cavity is obtained.

The transition period refers to the time required for the pump light to transform into laser light in the laser resonator. In the embodiment of the present disclosure, the laser light intensity required by the multi-pulse laser in the next pumping cycle is prepared before the start time of the next pumping cycle immediately adjacent to the current pumping cycle.

For example, continuing the above example, when the current detection time point is 0.5s, the start time point of the next pumping cycle next to the current pumping cycle is 3s, then the transition time period=3s-0.5s=2.5s is obtained; the current detection time When the point is 1.5s, the start time point of the next pumping cycle immediately adjacent to the current pumping cycle is 3s, then the transition time period=3s−1.5s=1.5s is obtained.

Step S105, obtaining a required transition rate based on the light intensity to be supplemented and the transition time period.

For example, continuing the above example, when the current detection time point is 0.5s, the light intensity to be supplemented is 5.2W/cm ² , the transition time period is 2.5s, and the required transition rate = 5.2W/cm ² ÷ 2.5s = 2.08W/ cm ² s; when the current detection time point is 1.5s, the light intensity to be supplemented is 10.7W/cm ² , the transition time period is 1.5s, and the required transition rate = 10.7W/cm ² ÷ 1.5s = 7.13W/cm ² s.

Step S106, obtaining the required pump light intensity of the adjustable pump source based on the required transition rate and the transition model of the laser resonator.

The jump model is a trained neural network model. The transition model can be obtained based on the previous historical required transition rate. For example, the required transition rate is used as a training sample to train the transition model of the laser resonator, so that the transition model can output the required pump light intensity of the adjustable pump source. The training process is not described in detail in this embodiment, and may be implemented by referring to various implementation manners in related technologies.

Step S107, generating the adjustment control instruction based on the required pump light intensity.

In the embodiment of the present disclosure, the laser light intensity in the laser resonator is detected in real time during the current pumping cycle, and the relationship between the current laser light intensity and the preset pulse loss light intensity in the next pumping cycle immediately adjacent to the current pumping cycle is obtained. Gap, in order to dynamically adjust the injection of the adjustable pump source in real time, before the start of the next pump cycle immediately adjacent to the current pump cycle, so that the adjustable pump source can generate the laser required to output multiple pulses for the next pump cycle light intensity.

In some specific embodiments, the adjustable pumping source includes a first adjustable pumping source and a second adjustable pumping source respectively connected to the controller with electrical signals.

Correspondingly, the controller is configured to generate the adjustment control instruction based on the required pump light intensity, including:

Step S107-1, obtaining a light intensity ratio based on the first maximum light intensity of the first adjustable pump source and the second maximum light intensity of the second adjustable pump source.

The first maximum light intensity refers to the maximum light intensity that the first adjustable pump source can inject into the pump light; the second maximum light intensity refers to the maximum light intensity that the second adjustable pump source can inject into the pump light. powerful. For example, if the first maximum light intensity is 0.6 W/cm ² and the second maximum light intensity is 0.8 W/cm ² , then the light intensity ratio is 3:4.

Step S107-2, allocating the required pump light intensity based on the light intensity ratio to obtain the first required pump light intensity and the second adjustable pump light intensity of the first adjustable pump source. Adjust the second required pump light intensity of the pump source.

For example, if the required pump light intensity is 2W/cm ² , the first required pump light intensity is 0.857W/cm ² , and the second required pump light intensity is 1.143W/cm ² .

Step S107-3, generating a first adjustment control instruction for the first adjustable pump source based on the first required pump light intensity, and,

Step S107-4, generating a second adjustment control command for the second adjustable pump source based on the second required pump light intensity.

The controller in the embodiment of the present disclosure obtains the laser light intensity in the laser resonator through a photodetector, and the controller controls the Q-switching module to output the laser in a multi-pulse manner through an output control command, and can realize multiple The pulse is adjustable in peak value, pulse width, pulse interval and/or period; the controller controls the adjustable pump source to adjust the intensity of the pump light by adjusting the control command, so that the Q-switching module can The multi-pulse laser is output outside in the next pumping cycle of the pumping cycle. Thus, the adjustable and controllable multi-pulse laser is realized.

Finally, it should be noted that each embodiment in this specification is described in a progressive manner, each embodiment focuses on the difference from other embodiments, and the same and similar parts of each embodiment can be referred to each other. As for the system or device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and for relevant details, please refer to the description of the method part.

The above embodiments are only used to illustrate the technical solutions of the present disclosure, rather than to limit them; although the present disclosure has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: it can still be described in the foregoing embodiments The recorded technical solutions are modified, or some of the technical features are replaced equivalently; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present disclosure.

Claims (7)

1. A multi-pulse laser, characterized in that, comprising: A photodetector and a controller, and at least one adjustable pump source, a laser resonator, a laser crystal, and a Q-switching module, wherein the Q-switching module and the laser crystal are arranged in the laser resonator; The adjustable pumping source is configured to inject pumping light into the laser resonant cavity along the optical path direction, and the pumping light intensity of the pumping light can be adjusted through the adjustment control command of the controller; The laser resonant cavity is a Z-shaped cavity, including an input mirror, a first reflective mirror, a second reflective mirror and an output mirror sequentially arranged along the optical path, and the laser crystal is located between the input mirror and the first reflective mirror , the Q-switching module is located between the second mirror and the output mirror; The Q-switching module is configured to make the laser resonator output laser light in a multi-pulse manner in each pumping cycle under the control of the output control instruction of the controller; The photodetector is arranged adjacent to the second reflector, and is configured to receive a detection signal output by the second reflector, so as to obtain the laser light intensity in the laser resonator; The controller is connected to the adjustable pumping source, the Q-switching module and the photodetector respectively, and is configured to generate corresponding pumping based on the preset multi-pulse characteristic information of each pumping cycle. A periodic output control command; in each pumping cycle, an adjustment control command is generated based on the detected laser light intensity and the preset pulse loss light intensity in the next pumping cycle immediately adjacent to the current pumping cycle; in response to the adjustment A control instruction, controlling the adjustable pump source to adjust the intensity of the pump light, so that the Q-switching module controls the laser resonator to output multi-pulse laser outward based on the output control instruction corresponding to the pumping period; Wherein, the multi-pulse laser includes a plurality of pulse lasers in one pumping cycle; the pumping cycle includes at least the pulse time period of each pulsed laser; the preset pulse loss light intensity is included in the current pumping cycle The sum of the preset loss light intensity of each pulse laser in the next pumping cycle; The controller is configured to generate adjustment control instructions based on the detected laser light intensity and the preset pulse loss light intensity in the next pumping cycle immediately adjacent to the current pumping cycle in each pumping cycle, including: Obtaining the current laser light intensity in the laser resonator, the current detection time point and the start time point of the next pumping cycle immediately adjacent to the current pumping cycle; obtaining a total loss light intensity based on the preset pulse loss light intensity and the preset inherent loss light intensity; Obtaining the light intensity to be supplemented based on the total lost light intensity and the current laser light intensity; Obtaining a transition time period of the laser in the laser resonator based on the start time point and the current detection time point; Obtaining a required transition rate based on the light intensity to be supplemented and the transition time period; Obtaining the required pump light intensity of the adjustable pump source based on the required transition rate and the transition model of the laser resonator; The adjustment control instruction is generated based on the required pump light intensity. 2. The multi-pulse laser according to claim 1, wherein the adjustable pumping source comprises a first adjustable pumping source and a second adjustable pumping source respectively connected to the controller electrical signal ; The controller is configured to generate the adjustment control instruction based on the required pump light intensity, comprising: obtaining a light intensity ratio based on a first maximum light intensity of the first adjustable pump source and a second maximum light intensity of the second adjustable pump source; Allocate the required pump light intensity based on the light intensity ratio to obtain the first required pump light intensity of the first adjustable pump source and the required pump light intensity of the second adjustable pump source. The second required pump light intensity; generating a first adjustment control instruction for the first adjustable pump source based on the first required pump light intensity, and, A second adjustment control command for the second adjustable pump source is generated based on the second required pump light intensity. 3. The multi-pulse laser according to claim 1, wherein the controller is configured to generate an output control instruction corresponding to the pumping cycle based on the preset multi-pulse feature information of each pumping cycle, including: A peak value control instruction corresponding to a corresponding pulse in each pumping cycle is generated based on a preset peak value of each pulse in each pumping cycle. 4. The multi-pulse laser according to claim 1, wherein the controller is configured to generate an output control instruction corresponding to the pumping cycle based on the preset multi-pulse feature information of each pumping cycle, including: A pulse width control instruction corresponding to a corresponding pulse in each pumping cycle is generated based on a preset pulse width value of each pulse in each pumping cycle. 5. The multi-pulse laser according to claim 1, wherein the controller is configured to generate an output control instruction corresponding to the pumping cycle based on the preset multi-pulse feature information of each pumping cycle, including: A pulse interval control instruction corresponding to two adjacent pulses in each pumping cycle is generated based on a preset pulse interval value between two adjacent pulses in each pumping cycle. 6. The multi-pulse laser according to claim 1, wherein the controller is configured to generate an output control command corresponding to the pumping cycle based on the preset multi-pulse feature information of each pumping cycle, including: A cycle control instruction corresponding to the pumping cycle is generated based on the preset cycle value of each pumping cycle. 7. The multi-pulse laser according to claim 1, wherein the total loss ε satisfies the following relationship: ε=Z+ξ(t) Z is the inherent loss, ξ(t) is the time-dependent loss introduced by the Q switch, and ξ(t) satisfies the following relationship:

Among them, Lq is the basic loss factor of Q-switching, T _a is the duration of high loss in one pumping cycle; T _b is the duration of low loss in one pumping cycle, k is the proportional coefficient of high and low loss, and t is time.

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