A laser generating device with adjustable pulse timing

Abstract

The pulse timing adjustable laser generating device of the present application comprises a timing controller, a driving power supply, a pump source, a beam collimation and shaping lens group, a beam combiner, a coupling lens group, a laser cavity mirror, a laser medium, a Q switch and a laser output coupling mirror. The multiple output ports of the timing controller are connected with the input ports of the multiple driving power supplies for generating multiple trigger signals and sending each trigger signal to the corresponding driving power supply, and each driving power supply is connected with a pump source. The present application has the advantages of compact structure, easy integration and timing programmable control pulse train working mode. Through increasing the time and sequence adjustment function of the electric modulation signal, multiple different wavelength pump sources or multiple same wavelength pump sources are pulsed pumped in time, multiple laser pulse sequences are generated in the laser cavity using the Q switching device, the problem that the pulse train laser timing is difficult to accurately control is broken through, and the application field of the pulse train laser is effectively expanded.

Description

Technical Field

[0001] This invention belongs to the field of laser technology and relates to a laser generating device with adjustable pulse timing. In particular, it refers to a laser technology that can control the number of laser pulse trains generated and the timing between each pulse train during laser oscillation. The laser pulse trains with the above-mentioned features can be controlled by programming and are lasers with compact structure, easy integration and scalability. Background Technology

[0002] Diode-pumped solid-state lasers (DPSSLs) are currently the most effective laser technology for achieving high pulse energy and high repetition rate output, and are mainly used in laser processing, laser diagnostics, optoelectronic countermeasures, and long-range lidar. Because there is a trade-off between high repetition rate laser pulses and increased laser pulse output energy, the pulse train laser pulse output mode has been proposed and applied in practice. Its greatest advantage is that it can maintain a constant average power while achieving high repetition rate and high energy output from sub-pulses within the pulse train.

[0003] As one of the mainstream methods for pulse train output, pulse pump Q-switching has advantages such as low thermal effect, simple structure, and intracavity adjustment, which greatly improves the intracavity energy utilization rate.

[0004] In laser oscillators, a pump source is used to pump the laser gain medium to generate population inversion. The center wavelength and bandwidth of the pump source's emission spectrum correspond to the center wavelength and bandwidth of the laser medium's absorption spectrum to achieve optimal pump light absorption efficiency. For a given gain medium, there are typically multiple gain absorption bands with different wavelengths; for example, Nd:YAG laser media has gain absorption bands with center wavelengths of 808 nm and 885 nm. Traditional pulse train lasers typically use a pump source emission spectrum whose center wavelength corresponds to a specific gain absorption wavelength of the laser medium. A Q-switched device within the laser cavity generates a continuous output laser pulse sequence. The pulse train laser output is controlled by adjusting the pump pulse width and frequency of the subsequent laser pulse amplifier. Therefore, the periodic pulse train output by the laser system usually contains only one pulse train with a single characteristic, limiting the application of pulse train lasers in precision laser manufacturing, laser material processing, and other fields. Summary of the Invention

[0005] The purpose of this invention is to provide a laser generating device with adjustable pulse timing, which has the advantages of compact structure, easy integration, and expandable time-domain programmable control pulse train working mode.

[0006] The objective of this invention is achieved through the following technical solution.

[0007] A pulse-time adjustable laser generating device includes a timing controller, a driving power supply, a pump source, a beam collimating and shaping lens group, a beam combiner, a coupling lens group, a laser cavity mirror, a laser medium, a Q-switching switch, and a laser output coupling mirror.

[0008] The output port of the timing controller is connected to the input port of the drive power supply to generate a trigger signal and send the trigger signal to the drive power supply to control the pump source; wherein, the drive power supply adopts a pulse drive power supply; the trigger signal is a pulse electrical signal, including a pump trigger signal and a Q-switching trigger signal.

[0009] The timing controller has multiple output ports, which can generate multiple trigger signals simultaneously. These signals are connected to the input ports of multiple drive power supplies, and each trigger signal is sent to the corresponding drive power supply. Each drive power supply is connected to a pump source, and the drive power supply acts on the corresponding pump source according to the received trigger signal. Each pump source corresponds to a beam collimating and shaping lens group, and all beam collimating and shaping lens groups together correspond to a beam combiner. The beam combiner, coupling lens group, laser cavity mirror, laser medium, Q-switching switch, and laser output coupling mirror are sequentially installed in the machine body.

[0010] The drive power supply is used to act on the pump source according to the received trigger signal.

[0011] Furthermore, the timing controller periodically sends a synchronous trigger signal to the drive power supply. The synchronous output signal has adjustable pulse width and frequency, which delays the action time of the drive power supply on the pump source, and the time interval is adjustable.

[0012] Furthermore, the timing controller can be a multi-channel signal generator or a circuit designed using a Field Programmable Gate Array (FPGA). The timing controller is also connected to a temperature control device for monitoring and controlling the temperature of the pump source.

[0013] Furthermore, the pump source is the pump source that generates long-pulse pump pulses. For a gain medium, there are usually multiple gain absorption bands with different wavelengths. Therefore, the pump source can be multiple pump sources with different wavelengths or multiple pump sources with the same wavelength, and the pump source can have different polarization states, which can be modified to a certain extent. The pump source is used to execute the control command of the pump trigger signal, applying the pump pulse to the laser medium.

[0014] Furthermore, the beam collimating and shaping lens group can be composed of various lenses such as spherical lenses, aspherical lenses, cylindrical lenses, and plane mirrors. Each pump source corresponds to one type of beam collimating and shaping lens group. The input side of the beam collimating and shaping lens group is positioned after the output side of the pump source to shape the pump pulse laser beam. After shaping by the lens group, collimated light is formed, thereby improving light transmission efficiency and reducing the beam divergence angle. The beam collimating lens group generally consists of lenses with different refractive indices and curvatures. These lenses, according to their different curvatures and positions, focus and modulate the pump beam, thereby ensuring the uniformity and stability of the beam during transmission.

[0015] Furthermore, the beam combiner combines multiple pump pulses from different directions, which have been shaped and collimated by the beam collimating and shaping lens group, into a single laser beam with accurate direction. The type of beam combiner is selected based on the characteristics of the pump source. When the beam combiner is a dispersive element, it can be an optical element with dispersive capabilities, such as a prism, Brewster's prism, diffraction grating, reflection grating, or crystal with an asymmetric structure. It combines pump light of different wavelengths from different directions into a single optical path. In practical applications, it can be combined as needed, depending on the pump wavelength range to be separated, refractive index, reflectivity, diffraction efficiency, and accuracy. When the beam combiner is a fiber beam combiner, it uses the refraction and total internal reflection of the fiber to couple pump light from different directions together and transmit it through the tail of the fiber. When the beam combiner is a polarization beam splitter, it can be a polarization beam splitter prism, a fiber-coupled output polarization beam splitter (combiner), etc., which can combine pump light of different polarization states from different directions into a single optical path for output. When the beam combiner is a 45° dichroic mirror with high-transmittance and high-reflection coatings on its front and back surfaces corresponding to the pump wavelength, it can combine pump light of different wavelengths from different directions into the same optical path for output.

[0016] Furthermore, the input side of the coupling lens group is positioned after the output side of the pump combiner, and is used to collimate and adjust the size of the pump pulse laser incident on the laser medium, so that the adjusted size of the pump pulse laser matches the laser fundamental mode in the laser resonant cavity. The coupling lens group includes convex lenses and concave lenses, and can be a combination of convex lenses or a combination of convex lenses and concave lenses.

[0017] Furthermore, a laser cavity mirror is used to transmit pump light and reflect the laser light generated by the laser medium.

[0018] Furthermore, the laser medium, based on the pump trigger signal, provides a gain region for the pump pulse. The laser medium includes, but is not limited to, crystalline materials, and can also be laser crystals, glasses, ceramics, optical fibers, dyes, Ti:sapphire, etc., that are single-doped, bonded, or cemented with rare-earth ions.

[0019] Furthermore, the Q-switching switch, based on the Q-switching trigger signal, is used to Q-switch the pump pulse laser that oscillates after gain, thereby obtaining a pulse train laser output.

[0020] Furthermore, a laser output coupling mirror is used to transmit the laser generated by the laser medium and reflect the pump light.

[0021] Furthermore, under the action of the timing controller, the pumping of the laser medium by multiple pump sources is delayed, and the corresponding pulsed laser beams are also delayed. The time interval between the pulsed laser beams is determined by the time interval between the pump sources.

[0022] Furthermore, under the built-in preset algorithm of the timing controller, the pump source controls the working cycle, duty cycle, and synchronization timing of the pump source, thereby programming and controlling the number of sub-pulses and the pulse delay between sub-pulses in the output pulse train laser, ultimately achieving the goal of arbitrarily adjustable pulse laser output.

[0023] Compared with the prior art, the present invention has the following advantages:

[0024] 1. This invention has a compact structure, reasonable design, is easy to integrate, and allows for programmable timing control of the pulse train working mode.

[0025] 2. This invention is an extended wavelength pulse-pumped Q-switched pulse train laser, which can overcome the problem of difficult precise control of pulse train laser timing.

[0026] 3. This invention can perform time-division pulse pumping on multiple pump sources of different wavelengths or multiple pump sources of the same wavelength by adding time and sequence adjustment functions to the electrical modulation signal. Multiple laser pulse sequences are generated in the laser cavity using Q-switching devices, which can overcome the problem of difficult precise control of the timing of laser pulse trains, thereby further realizing precise control of the interval distribution of sub-pulses in the pulse train.

[0027] 4. This invention can effectively expand the application fields of pulse train lasers.

[0028] The pulse train laser of this invention employs multiple pump sources of different wavelengths or multiple pump sources of the same wavelength for time-division pulse pumping. A Q-switching device within the laser cavity generates multiple laser pulse sequences, and the timing of each sequence can be controlled. This pulse-time-tunable laser can achieve more accurate and efficient laser output by adjusting parameters such as the laser time interval, pulse width, and repetition frequency, and can be used in various research and application fields. For example, in materials processing and manufacturing, it can be used for micromachining and surface modification; in laser displays and optical communications, it can improve resolution and communication bandwidth; in life sciences and medicine, it can be used to image rapidly changing biological systems, such as the heart, and can also be used for exfoliation, phototherapy, cutting, and analysis; furthermore, it has significant application value in optical measurement and optoelectronics, as well as in the research of terahertz time-domain optics. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the embodiments or the prior art will be described below.

[0030] Figure 1 A schematic diagram of a laser device for generating pulse trains using conventional extracavity modulation;

[0031] In the diagram, P1 is the oscillator stage drive power supply; P2 is the amplifier stage drive power supply; L1 is the oscillator stage pump source; L2 is the amplifier stage pump source; C1 is the oscillator stage coupling lens group; C2 is the amplifier stage coupling lens group; M1 is the oscillator stage cavity mirror; M2 is the oscillator stage output coupling mirror; g1 is the oscillator stage gain medium; g2 is the amplifier stage gain medium; Q is the Q-switching device; and Syn is the external control circuit.

[0032] Figure 2 Timing diagram for generating pulse train lasers using conventional extracavity modulation;

[0033] Figure 3 This is a schematic diagram of the laser device structure for generating pulse trains using the pulse-pumped Q-switching method of the present invention.

[0034] In the diagram, P is the pulsed drive power supply; L is the pump source; C is the coupling lens group; M1 is the laser cavity mirror; g is the laser medium; Q is the Q-switching device; and M2 is the output coupling mirror.

[0035] Figure 4 This is a timing diagram of the pulse-pumped Q-switching method for generating pulse train lasers according to the present invention.

[0036] Figure 5 A schematic diagram of a laser structure with adjustable pulse timing provided for an embodiment of the present invention;

[0037] In the diagram, 1-timing controller; 11, 21…n1-driving power supply; 12, 22…n2-pump source; 13, 23…n3-beam collimating and shaping lens group; 2-beam combiner; 3-coupled lens group; 4-laser cavity mirror; 5-laser medium; 6-Q-switching device; 7-output coupling mirror.

[0038] Figure 6 This is a schematic diagram of the structural composition of Embodiment 1 of the present invention, which is based on a laser with adjustable pulse timing.

[0039] Figure 7 This is a schematic diagram of the structural composition of Embodiment 2 of the present invention, which is based on a laser with adjustable pulse timing.

[0040] Figure 8 This is a schematic diagram of the structural composition of embodiment 3 of the present invention, which is based on a laser with adjustable pulse timing.

[0041] Figure 9 This is a schematic diagram of the structural composition of embodiment 4 of the present invention, which is based on a laser with adjustable pulse timing. Detailed Implementation

[0042] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to specific embodiments and accompanying drawings. The illustrative embodiments and descriptions of the present invention are used to explain the present invention, but are not intended to limit the present invention.

[0043] As mentioned above, the starting point of this invention for a pulse-time adjustable laser generation device is to achieve time-adjustable laser pulse train based on the pulse-pumped Q-switching method, thereby designing a laser with a reasonable design, compact structure, easy integration, and time-programmable control of the pulse train working mode to meet the application needs of related fields.

[0044] Figure 1 This diagram illustrates a specific embodiment of a laser device for generating pulse trains using conventional extracavity modulation, including: P1 - oscillator stage drive power supply; P2 - amplification stage drive power supply; L1 - oscillator stage pump source; L2 - amplification stage pump source; C1 - oscillator stage coupling lens group; C2 - amplification stage coupling lens group; M1 - oscillator stage cavity mirror; M2 - oscillator stage output coupling mirror; g1 - oscillator stage gain medium; g2 - amplification stage gain medium; Q - Q-switching device; Syn - external control circuit, wherein:

[0045] After the external control circuit Syn sends a trigger signal to the oscillator stage, the oscillator stage drive circuit P1 drives the oscillator stage pump source L1 to execute the control command of the pump signal, generating a pump pulse with a lower frequency and a longer pulse width. This pump pulse changes the size of the light spot through the oscillator stage coupling lens group C1, better matching the mode with the laser radius in the oscillator stage gain medium g1 in the resonant cavity, thus generating oscillating light. After the oscillator stage pump source starts working, the Q-switching medium generates a narrow pulse width Q-switched laser sequence by repeatedly switching the Q-switching switch on and off. The frequency of these Q-switched laser sequences is the frequency corresponding to the pump trigger signal.

[0046] Furthermore, after the oscillator stage generates a narrow pulse laser sequence, the pump pulse size of the amplification stage is adjusted to match the spot size of the narrow pulse laser from the oscillator stage via the coupling lens group C2. Then, the amplification stage, with its adjusted size, amplifies the power of the narrow pulses, resulting in a narrow pulse train mode. The amplification stage pump source L2 is synchronized with the oscillator stage pump source L1 by the external control circuit Syn, achieving maximum pump efficiency.

[0047] Figure 2 The diagram illustrates the timing relationships of pulse train lasers generated by conventional external cavity modulation, showing the timing relationships between the oscillator-stage Q-switched pulse sequence and the amplification-stage pulse train laser output. It can be seen that a continuous output laser pulse sequence is generated within the laser cavity using a Q-switched device. The controlled output of the external cavity pulse train laser is achieved by adjusting the pump pulse width and frequency of the subsequent laser pulse amplifier. Therefore, the periodic pulse train output by the laser system typically contains only one pulse train with a single characteristic, and the output efficiency is relatively low.

[0048] Figure 3 A schematic diagram of a laser device for generating pulse trains using pulse-pumped Q-switching is shown. This is a highly efficient pulse train generation scheme combining pulse pumping and intracavity modulation. The device includes: P-pulsed driving power supply; L-pump source; C-coupled lens group; M1-laser cavity mirror; g-laser medium; Q-Q-switching device; and M2-output coupling mirror. The pump source L is driven by the pulsed driving power supply P to form a long pulse pump. A Q-switching medium is inserted into the resonant cavity. By controlling the pumping time and energy of the pump source and the operating state of the Q-switching medium, flexible selection of the laser pulse train can be achieved.

[0049] Figure 4 The timing relationship diagram for pulse train laser generated by the pulse pump Q-switching method shows that, compared with the external cavity modulated pulse train laser output, it has the advantage of flexible and controllable pulse train laser parameters.

[0050] Whether it is the traditional external cavity modulation pulse train generation method or the pulse pump Q-switching method, the center wavelength of the emission spectrum of the pump source usually corresponds to a certain gain absorption wavelength of the laser medium, so that the periodic pulse train output by the laser system usually contains only a pulse train with a single characteristic.

[0051] Figure 5 This is a schematic diagram of a pulse-timing-tunable laser structure provided in an embodiment of the present invention. Based on the flexible selection of laser pulse trains using the pulse-pumped Q-switching method, multiple pump sources of different wavelengths or multiple pump sources of the same wavelength are used for time-division pulse pumping. Multiple laser pulse sequences are generated within the laser cavity using a Q-switching device, and the timing of each sequence can be controlled. Wherein, 1-timing controller; 11, 21…n1-driving power supply; 12, 22…n2-pump source; 13, 23…n3-beam collimating and shaping lens group; 2-beam combiner; 3-coupled lens group; 4-laser cavity mirror; 5-laser medium; 6-Q-switching device; 7-output coupling mirror.

[0052] The timing controller has multiple output ports, which can generate multiple trigger signals simultaneously. These signals are connected to the input ports of multiple drive power supplies, and each trigger signal is sent to the corresponding drive power supply. Each drive power supply is connected to a pump source, and the drive power supply acts on the corresponding pump source according to the received trigger signal. Each pump source corresponds to a beam collimating and shaping lens group, and all beam collimating and shaping lens groups together correspond to a beam combiner. The beam combiner, coupling lens group, laser cavity mirror, laser medium, Q-switching switch, and laser output coupling mirror are sequentially installed in the machine body.

[0053] The drive power supply is used to apply power to the pump source based on the received trigger signal. The drive power supply is a pulsed drive power supply.

[0054] The timing controller can generate a series of different timing signals according to preset rules to ensure that each part of the circuit operates according to the specified timing sequence. At the same time, the timing controller 1 has multiple output ports, which are connected to the input ports of the drive power supplies 11, 21...n1 to generate multiple trigger signals and send the trigger signals to the drive power supplies 11, 21...n1 to control the pump sources 12, 22...n2.

[0055] The trigger signal is a pulsed electrical signal, including a pump trigger signal and a Q-switching trigger signal. The timing controller 1 periodically sends synchronous trigger signals to the drive power supplies 11, 21…n1. The synchronous output signal has adjustable pulse width and frequency, which delays the action time of the drive power supplies 11, 21…n1 on the pump sources 12, 22…n2, and the time interval is adjustable.

[0056] The timing controller can be a multi-channel signal generator or a circuit designed using a Field Programmable Gate Array (FPGA). The timing controller is also connected to a temperature control device for monitoring and controlling the temperature of the pump source.

[0057] Pump sources 12, 22…n2 are used to execute the control commands of the pump trigger signal, applying pump pulses to the laser medium 5. Pump sources 12, 22…n2 are the pump sources that form long-pulse pump pulses. For a gain medium, there are usually multiple gain absorption bands of different wavelengths; therefore, pump sources 12, 22…n2 can be multiple pump sources of different wavelengths or multiple pump sources of the same wavelength, and their polarization states can also be changed. Pump sources can have different polarization states.

[0058] The beam collimating and shaping lens group 13, 23…n3 is positioned after the output side of the pump sources 12, 22…n2 on the input side. It is used to improve the focusing power and lateral width of the pump pulse laser, thereby enhancing the efficiency and stability of the pump light. The beam collimating lens group typically consists of lenses with different refractive indices and curvatures. These lenses, based on their curvatures and positions, focus and modulate the pump beam, ensuring the uniformity and stability of the beam during transmission. The beam collimating and shaping lens group can be composed of various combinations of spherical lenses, aspherical lenses, cylindrical lenses, and plane mirrors.

[0059] Beam combiner 2 combines multiple pump light pulses, shaped and collimated by beam collimating and shaping lens group 13, 23…n3, into a single laser beam. The type of beam combiner 2 is selected based on the characteristics of pump sources 12, 22…n2. For example: when the beam combiner is a dispersive element, prisms and gratings can be used to combine pump light from different directions and wavelengths into a single output direction; when the beam combiner is a fiber beam combiner, the fiber can couple pump light from different directions into a single fiber for output; a free-space beam combiner composed of lenses and mirrors focuses dispersed pump light onto a single point, thereby enhancing the directionality of the beam and outputting it in the same optical path direction; a polarization beam splitter can combine pump light from different directions and different polarization states into a single optical path for output; for pump light of different wavelengths, 45° dichroic mirrors with high-transmittance and high-reflection coatings corresponding to the corresponding wavelengths on their front and back surfaces can combine pump light from different directions and wavelengths into the same optical path for output.

[0060] The input side of the coupling lens group 3 is positioned after the output side of the pump combiner 2. It is used to collimate and adjust the size of the pump pulse laser incident on the laser medium 5, so that the adjusted size of the pump pulse laser matches the laser fundamental mode in the laser resonant cavity. The coupling lens group includes convex lenses and concave lenses, which can be a combination of convex lenses or a combination of convex lenses and concave lenses.

[0061] Laser cavity mirror 4 is used to transmit pump light and reflect the laser generated by laser medium 5.

[0062] Laser medium 5 provides the gain region for the pump pulse according to the pump trigger signal. Laser medium includes, but is not limited to, crystal materials, and can also be laser crystals, glass, ceramics, optical fibers, dyes, titanium sapphire, etc., that are doped with, bonded with, or cemented with rare earth ions.

[0063] The Q-switching device 6, based on the Q-switching trigger signal, is used to Q-switch the pump pulse laser that oscillates after gain, thereby obtaining a pulse train laser output. The Q-switching device can be an active Q-switching element or a passive Q-switching medium.

[0064] The output coupling mirror 7 is used to transmit the laser generated by the laser medium 5 and to reflect the pump light.

[0065] Under the action of timing controller 1, pump sources 12, 22...n2 have a delay in pumping the laser medium 5, and the corresponding pulse train laser also has a delay. The time interval between pulse train lasers is determined by the time interval between pump sources 12, 22...n2.

[0066] Under the built-in preset algorithm of timing controller 1, the working cycle, duty cycle and synchronization timing of pump sources 12, 22...n2 are controlled, thereby controlling the number of sub-pulses in the output pulse train laser and the pulse delay between sub-pulses, ultimately achieving the purpose of arbitrarily adjustable pulse laser output.

[0067] Example 1:

[0068] See Figure 6 , Figure 6 This is a schematic diagram of a laser structure with adjustable pulse timing, pumped by multiple pump sources of different wavelengths and combined with a dispersive element.

[0069] In the figure, 1-timing controller; 11, 21, 31-drive power supply; 12, 22, 32-pump source; 13, 23, 33-beam collimating and shaping lens group; 2-dispersion element; 3-coupled lens group; 4-laser cavity mirror; 5-laser medium; 6-Q-switching device; 7-output coupling mirror.

[0070] The timing controller 1 sends the generated periodic synchronous trigger signal to the drive power supplies 11, 21, and 31, causing a delay in the action time of the drive power supplies 11, 21, and 31 on the pump sources 12, 22, and 32, and the time interval is adjustable, thereby controlling the pump sources 12, 22, and 32. The pump sources 12, 22, and 32 then execute the control command of the pump trigger signal, applying pump pulses to the laser medium 5. The pump sources 12, 22, and 32 are pump sources for pulses of different wavelengths, and the gain medium 5 can absorb and lasing lasers from all these pump wavelengths. The beam collimating and shaping lens group 13, 23, and 33 shapes the pump pulse laser beam, forming collimated light after shaping, thereby improving light transmission efficiency and reducing the beam divergence angle. The dispersive element 2 combines the three dispersed pump pulses of different wavelengths, shaped and collimated by the beam collimating and shaping lens group 13, 23, and 33, into a single laser beam. The dispersive element 2 can be any optical element with dispersive capabilities, such as a prism, Brewster's prism, diffraction grating, reflection grating, or crystal with an asymmetric structure. In practical applications, they can be combined as needed. The application of different dispersive elements depends on factors such as the wavelength range to be separated, refractive index, reflectivity, diffraction efficiency, and accuracy. The coupling lens group 3 is used to collimate and adjust the size of the pump pulse laser incident on the laser medium 5. The laser cavity mirror 4 is used to transmit the pump light and reflect the laser generated by the laser medium 5. The laser medium 5 provides a gain region for the pump pulse, forming a lasing under time-division pumping of three pump pulses. The Q-switching device 6 is used to Q-switch the lasing laser according to the Q-switching trigger signal, thereby obtaining a pulse train laser output. The output coupling mirror 7 is used to transmit the laser generated by the laser medium 5 and reflect the pump light.

[0071] Example 2:

[0072] See Figure 7 , Figure 7 This is a schematic diagram of a laser structure with adjustable pulse timing, which is pumped by multiple pump sources and combined with an optical fiber combiner according to the present invention.

[0073] In the diagram, 1-timing controller; 11, 21…n1-driving power supply; 12, 22…n2-pump source; 13, 23…n3-beam collimating and shaping lens group; 2-fiber combiner; 3-coupled lens group; 4-laser cavity mirror; 5-laser medium; 6-Q-switching device; 7-output coupling mirror.

[0074] The timing controller 1 sends the generated periodic synchronous trigger signal to the driving power supplies 11, 21…n1, causing a delay in the action time of the driving power supplies 11, 21…n1 on the pump sources 12, 22…n2, with the time interval being adjustable, thereby controlling the pump sources 12, 22…n2. The pump sources 12, 22…n2 then execute the control command of the pump trigger signal, applying the pump pulse to the laser medium 5. Here, pump sources 12, 22…n2 are the pump sources for the pulses. The beam collimating and shaping lens group 13, 23…n3 shapes the pump pulse laser beam, which is then coupled into the transmission fiber after shaping. The fiber combiner 2 combines the multiple pump light transmission fibers into a single fiber for output. The coupling lens group 3 is used to collimate and adjust the size of the pump pulse laser incident on the laser medium 5. The laser cavity mirror 4 is used to transmit the pump light and reflect the laser generated by the laser medium 5. Laser medium 5 provides a gain region for the pump pulses, forming a lasing beam under time-division pumping of multiple pump pulses. Q-switching device 6, based on a Q-switching trigger signal, is used to Q-switch the lasing laser, thereby obtaining a pulse train laser output. Output coupling mirror 7 transmits the laser generated by laser medium 5 and reflects the pump light.

[0075] Example 3:

[0076] See Figure 8 , Figure 8 This is a schematic diagram of the laser structure of the present invention, which allows for adjustable pulse timing under pumping from pump sources of different polarization states or wavelengths.

[0077] In the diagram, 1-timing controller; 11, 21-drive power supply; 12, 22-pump source; 13, 23-beam collimating and shaping lens group; 2-beam splitter; 3-coupled lens group; 4-laser cavity mirror; 5-laser medium; 6-Q-switching device; 7-output coupling mirror.

[0078] The timing controller 1 sends the generated periodic synchronous trigger signal to the drive power supplies 11 and 21, causing a delay in the action time of the pump sources 12 and 22 by the drive power supplies 11 and 21, and the time interval is adjustable, thereby controlling the pump sources 12 and 22. The pump sources 12 and 22 then execute the control command of the pump trigger signal, applying the pump pulse to the laser medium 5. The pump sources 12 and 22 can be pulse pump sources with different polarization states or pulse pump sources with different wavelengths. The beam collimating and shaping lens groups 13 and 23 shape the pump pulse laser beam, forming collimated light after shaping. Beam splitter 2 combines the shaped and collimated two pump pulses into the same optical channel for output. When pump light with different polarization states is incident, beam splitter 2 acts as a polarization beam splitter, combining the light into a single output channel based on the polarization state of the input pump light in both channels. Beam splitter 2 can be a polarization beam-splitting prism, fiber-coupled output polarization beam splitter (combiner), etc. When pump light with different wavelengths is incident, beam splitter 2 acts as a 45° dichroic mirror, highly transmitting one wavelength while highly reflecting the other, thus combining them into a single output light. Coupled lens group 3 is used to collimate and adjust the size of the pump pulse laser incident on the laser medium 5. Laser cavity mirror 4 is used to transmit the pump light and reflect the laser generated by the laser medium 5. Laser medium 5 provides a gain region for the pump pulses, forming lasing under time-division pumping of multiple pump pulses. Q-switching device 6 is used to Q-switch the lasing laser according to the Q-switching trigger signal, thereby obtaining a pulse train laser output. The output coupling mirror 7 is used to transmit the laser generated by the laser medium 5 and to reflect the pump light.

[0079] It should be further noted that in a specific embodiment of this modulated pulsed laser, the pumping directions of the two pump sources are approximately perpendicular, and the laser crystal is end-face pumped, which can reduce the size of the solid-state laser, thereby making it easier to achieve miniaturization and low cost.

[0080] Example 4:

[0081] See Figure 9 , Figure 9 This is a schematic diagram of the laser structure for which the pulse timing can be adjusted under different polarization states and different wavelength pump sources according to the present invention.

[0082] In the diagram, 1-timing controller; 11, 21, 31-drive power supply; 12, 22, 32-pump source; 13, 23, 33-beam collimating and shaping lens group; 2-beam combiner; 20-beam splitter; 3-coupled lens group; 4-laser cavity mirror; 5-laser medium; 6-Q-switching device; 7-output coupling mirror.

[0083] The timing controller 1 sends the generated periodic synchronous trigger signal to the drive power supplies 11, 21, and 31, causing a delay in the action time of the pump sources 12, 22, and 32 by the drive power supplies 11, 21, and 31, and the time interval is adjustable, thereby controlling the pump sources 12, 22, and 13. Then, the pump sources 12, 22, and 13 execute the control command of the pump trigger signal, applying the pump pulse to the laser medium 5. Pump sources 12 and 22 are pulse pump sources with different polarization states, and pump sources 12 and 32 are pulse pump sources with different wavelengths. Beam collimating and shaping lens groups 13, 23, and 33 shape the pump pulse laser beam, forming collimated light after shaping. Beam splitter 2 is a polarization beam splitter, and beam splitter 20 is a 45° dichroic mirror; both combine the shaped and collimated pump pulses into the same optical channel for output. The coupling lens group 3 is used to collimate and adjust the size of the pump pulse laser incident on the laser medium 5. The laser cavity mirror 4 is used to transmit the pump light and reflect the laser generated by the laser medium 5. The laser medium 5 provides a gain region for the pump pulse, forming a lasing under time-division pumping of multiple pump pulses. The Q-switching device 6 is used to Q-switch the lasing laser according to the Q-switching trigger signal, thereby obtaining a pulse train laser output. The output coupling mirror 7 is used to transmit the laser generated by the laser medium 5 and reflect the pump light.

[0084] The above description is merely a preferred embodiment of the present invention, and the embodiments of the present invention are intended to cover all such substitutions, modifications, and variations falling within the broad scope of the appended claims. For those skilled in the art, any omissions, modifications, equivalent substitutions, improvements, variations, etc., made without departing from the technical principles of the present invention should be included within the protection scope of the present invention.

[0085] For example:

[0086] (1) The pump source of the present invention is a pump source that forms a long pulse pump pulse. For a laser working substance with multiple gain absorption bands of different wavelengths, the pump source can be multiple pump sources of different wavelengths or multiple pump sources of the same wavelength. The polarization state of the pump source can also be changed.

[0087] (2) The combiner of the present invention can be selected according to the characteristics of the pump source. When a prism or grating is used as a combiner, pump light of different wavelengths from different directions can be combined into one optical path; when an optical fiber combiner is used as a combiner, pump light from different directions can be coupled into one optical fiber for output; when a polarization beam splitter is used as a combiner, pump light of different polarization states from different directions can be combined into one optical path for output; when a 45° dichroic mirror with high transmittance and high reflectance coatings of corresponding wavelengths on its front and rear surfaces is used as a combiner for pump light of different wavelengths, pump light of different wavelengths from different directions can be combined into the same optical path for output.

[0088] (3) The Q-switching device of the present invention can be an active Q-switching element or a passive Q-switching working substance, and is not limited to a saturable absorber crystal. It can be any Q-switching working substance that can absorb a certain degree of laser wavelength emitted by the laser working substance.

Claims

1. A laser generating device with adjustable pulse timing, characterized in that: The system includes a timing controller, multiple drive power supplies, multiple pump sources, multiple beam collimating and shaping lens groups, a beam combiner, a coupling lens group, a laser cavity mirror, a laser medium, a Q-switching switch, and a laser output coupling mirror. The timing controller's multiple output ports are connected to the input ports of the multiple drive power supplies to generate multiple trigger signals and send each trigger signal to its corresponding drive power supply. Each drive power supply is connected to one pump source, and the drive power supply acts on the corresponding pump source according to the received trigger signal. Each pump source corresponds to one beam collimating and shaping lens group, and all beam collimating and shaping lens groups together correspond to one beam combiner. The beam combiner, coupling lens group, laser cavity mirror, laser medium, Q-switching switch, and laser output coupling mirror are sequentially installed within the system. The drive power supply adopts a pulsed drive power supply; the trigger signal is a pulsed electrical signal, including a pump trigger signal and a Q-switching trigger signal; The timing controller periodically sends a synchronous trigger signal to the drive power supply. The pulse width and frequency of the synchronous output signal are adjustable, which delays the action time of the drive power supply on the pump source, and the time interval is adjustable. The timing controller is a multi-channel signal generator or a circuit designed using a field-programmable gate array; the timing controller is also connected to a temperature control device for monitoring and controlling the temperature of the pump source; Under the control of the timing controller, the pump source controls the number of sub-pulses and the pulse delay between sub-pulses in the output pulse train laser by controlling the pump source's working cycle, duty cycle, and synchronization timing, ultimately achieving the goal of arbitrarily adjustable pulse laser output.

2. The laser generating device with adjustable pulse timing according to claim 1, characterized in that: The pump source is a pump source that forms a long pulse pump pulse; for a gain medium with multiple gain absorption bands of different wavelengths, the pump source can be multiple pump sources of different wavelengths or multiple pump sources of the same wavelength; and the pump source can change its polarization state to a certain extent and can have different polarization states; the pump source is used to execute the control command of the pump trigger signal and apply the pump pulse to the laser medium.

3. A laser generating device with adjustable pulse timing according to claim 1 or 2, characterized in that: The beam collimating and shaping lens group uses a combination of various lenses, including spherical lenses, aspherical lenses, cylindrical lenses, and plane lenses. Each pump source corresponds to a beam collimating and shaping lens group. The light-inlet side of the beam collimating and shaping lens group is located after the light-outlet side of the pump source. It is used to shape the pump pulse laser beam, forming collimated light after shaping by the lens group, thereby improving the light transmission efficiency and reducing the beam divergence angle.

4. A laser generating device with adjustable pulse timing according to claim 1 or 2, characterized in that: The beam combiner can be selected based on the characteristics of the pump source. When the beam combiner is a dispersive element, optical elements with dispersive capabilities, such as prisms, Brewster prisms, diffraction gratings, reflection gratings, and crystals with asymmetric structures, are used to combine pump light of different wavelengths from different directions into a single optical path. In practical applications, it can be combined as needed, depending on the required pump wavelength range, refractive index, reflectivity, diffraction efficiency, and accuracy. When the beam combiner is a fiber optic beam combiner, the refraction and total internal reflection of the fiber are used to couple pump light from different directions together and transmit it through the tail of the fiber. When the beam combiner is a polarization beam splitter, polarization beam splitting prisms and fiber-coupled output polarization beam splitters can be used to combine pump light of different polarization states from different directions into a single optical path for output. When the beam combiner is a 45° dichroic mirror with high-transmittance and high-reflection coatings corresponding to the pump wavelength on its front and back surfaces respectively, it can combine pump light of different wavelengths from different directions into the same optical path for output. The beam combiner combines multiple pump light pulses from different directions, which have been shaped and collimated by the beam collimating and shaping lens group, into a single laser beam with accurate direction.

5. A laser generating device with adjustable pulse timing according to claim 1 or 2, characterized in that: The coupling lens group employs a combination of convex lenses or a combination of convex and concave lenses. The light-inlet side of the coupling lens group is positioned after the light-outlet side of the pump combiner, and is used to collimate and adjust the size of the pump pulse laser incident on the laser medium so that the adjusted size of the pump pulse laser matches the laser fundamental mode in the laser resonant cavity.

6. A laser generating device with adjustable pulse timing according to claim 1 or 2, characterized in that: Under the action of the timing controller, the pumping of the laser medium by multiple pump sources has a delay, and the corresponding pulsed laser also has a delay. The time interval between the pulsed lasers is determined by the time interval between the pump sources.

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