Laser pulse repetition frequency regulator and solid pulse laser

Abstract

The present invention relates to a laser pulse repetition frequency regulator and a solid pulse laser, wherein the regulator comprises: a first half-wave plate, a first polarization beam splitter prism, a first reflector group, a moving component, a second reflector group and a second half-wave plate; the first half-wave plate and the first polarization beam splitter prism are arranged in sequence along the wave transmission direction of the incident light; the first polarization beam splitter prism is used to separate the incident light into a first polarization light and a second polarization light; the first polarization light is output; the second polarization light passes through the first reflector group, the second reflector group and the second half-wave plate in sequence and then returns to the first polarization beam splitter prism for separation again, and the separation direction is along the direction of the first polarization light and the second polarization light; the moving component is at least used to drive the first reflector group to move, so as to change the time from the second polarization light being emitted from the first polarization beam splitter prism to returning to the first polarization beam splitter prism.

Description

Technical Field

[0001] The invention relates to the field of laser equipment, and in particular to a laser pulse repetition frequency regulator and a solid pulse laser. Background Art

[0002] In recent years, high repetition rate femtosecond pulse lasers have important applications in basic research and industry. High repetition rate femtosecond lasers often have higher sampling rates, and are used in laser ranging, high-speed optical sampling, optical communications, and bio-imaging. For example, in the field of precision measurement, the comb teeth of high repetition rate femtosecond pulses are easy to distinguish, which can achieve accurate calibration of astronomical spectra when searching for Earth-like exoplanets; in bio-imaging applications, high repetition rate ultrafast lasers can increase the signal feedback rate, reduce the photobleaching and photodamage of fluorescent proteins, significantly improve the quality of bio-imaging, and assist in medical diagnosis. Therefore, high-performance GHz repetition rate ultrashort pulse lasers have great market demand and development prospects.

[0003] At present, the commonly used technical solutions for ultra-high repetition rate femtosecond lasers (GHz) in the industry include harmonic mode locking, active mode locking, and fundamental mode fiber mode locking. Harmonic mode locking usually has the disadvantage of high phase noise, and active mode locking requires an additional high-frequency signal generator to assist in the generation of high repetition rate optical pulses, which is expensive. Although fiber mode-locked lasers have the advantages of compact structure and high beam quality, nonlinear effects such as self-phase modulation (SPM) and stimulated Raman scattering (SRS) in the optical fiber also limit the output of high energy. In addition, the repetition frequency of passive mode locking is inversely proportional to the length of the resonant cavity. In order to obtain a high repetition frequency, the length of the resonant cavity fiber needs to be greatly shortened, which brings high difficulty to the integration of the device; when the repetition frequency increases, the passive mode locking threshold and self-starting time also increase and extend accordingly, which requires increasing the pump power. Whether it is the increase in pump power or the extension of self-starting time, it will bring great damage risks to the fiber device in the cavity, resulting in its service life. The above problems need to be solved urgently. Summary of the invention

[0004] The invention discloses a laser pulse repetition frequency regulator and a solid pulse laser, aiming to solve the technical problems existing in the prior art.

[0005] The present invention adopts the following technical solutions:

[0006] On the one hand, the present invention provides a laser pulse repetition frequency regulator, which includes: a first half-wave plate, a first polarization beam splitter prism, a first reflector group, a moving component, a second reflector group and a second half-wave plate; the first half-wave plate and the first polarization beam splitter prism are arranged in sequence along the wave transmission direction of the incident light; the first polarization beam splitter prism is used to separate the incident light into a first polarization light and a second polarization light; the first polarization light is the output light; the second polarization light passes through the first reflector group, the second reflector group and the second half-wave plate in sequence and then returns to the first polarization beam splitter prism for separation again, and the separation direction is along the direction of the first polarization light and the second polarization light; the moving component is at least used to drive the first reflector group to move so as to change the time from the second polarization light being emitted from the first polarization beam splitter prism to returning to the first polarization beam splitter prism.

[0007] In the laser pulse repetition frequency regulator of the present invention, the propagation directions of the first polarized light and the second polarized light are perpendicular to each other, and the light intensity ratio is 1:1; and the incident light is parallel to the first polarized light.

[0008] The laser pulse repetition frequency regulator of the present invention further comprises an optical signal enhancement device; the optical signal enhancement device is used to enhance the signal of the second polarized light.

[0009] In the laser pulse repetition frequency regulator of the present invention, the optical signal enhancement device comprises a laser gain medium and a pump laser; the laser gain medium is arranged between the first reflector group and the second reflector group;

[0010] The pump laser can emit pump light to the laser gain medium through the second reflection mirror group.

[0011] In the laser pulse repetition frequency regulator of the present invention, the second reflector group includes a third reflector and a fourth reflector; the third reflector and the fourth reflector are arranged in sequence along the light propagation direction; the pump laser enters the laser gain medium after being transmitted through the third reflector.

[0012] The laser pulse repetition frequency regulator of the present invention further comprises a waveform editor; the waveform editor is used to edit the waveform of the second polarized light.

[0013] In the laser pulse repetition frequency regulator of the present invention, the waveform editor includes an acousto-optic modulator and an arbitrary waveform generator; the arbitrary waveform generator is used to control the acousto-optic modulator to perform waveform editing on the second polarized light.

[0014] In the laser pulse repetition frequency regulator of the present invention, the acousto-optic modulator includes an acousto-optic medium and a piezoelectric transducer; the piezoelectric transducer can generate ultrasonic waves of the same frequency based on the carrier frequency emitted by the arbitrary waveform generator; the acousto-optic medium receives the ultrasonic waves to change the propagation direction of the second polarized light.

[0015] In the laser pulse repetition frequency regulator of the present invention, the waveform editor is arranged between the second reflector group and the second half-wave plate.

[0016] The laser pulse repetition frequency regulator of the present invention further comprises a negative dispersion compensation device; the negative dispersion compensation device is used to perform negative dispersion compensation on the second polarized light.

[0017] In the laser pulse repetition frequency regulator of the present invention, the negative dispersion compensation device is arranged between the third reflecting mirror and the fourth reflecting mirror.

[0018] In the laser pulse repetition frequency regulator of the present invention, the negative dispersion compensation device includes a second polarization beam splitter prism, a negative dispersion compensation component and a polarization state adjustment component; the second polarization beam splitter prism is used to reflect the second polarized light to the negative dispersion compensation component; the negative dispersion compensation component is used to perform negative dispersion compensation on the second polarized light and adjust the polarization state so that the second polarized light enters the polarization state adjustment component after being transmitted through the second polarization beam splitter prism; the polarization state adjustment component is used to adjust the polarization state of the transmitted light of the second polarization beam splitter prism and then reflect and output it through the second polarization beam splitter prism.

[0019] In the laser pulse repetition frequency regulator of the present invention, the light reflected and output by the second polarization beam splitter prism is in the same direction as the direction in which the second polarized light enters the second polarization beam splitter prism.

[0020] In the laser pulse repetition frequency regulator of the present invention, the negative dispersion compensation component includes a quarter wave plate, a transmission compression grating and a first total reflection mirror. The second polarized light passes through the quarter wave plate, the transmission compression grating and the first total reflection mirror in sequence, is reflected by the first total reflection mirror, passes through the transmission compression grating and the quarter wave plate again, and then enters the second polarization splitter prism.

[0021] In the laser pulse repetition frequency regulator of the present invention, the polarization state adjustment component includes a half-wave plate and a second total reflection mirror; the transmitted light through the second polarization beam splitter prism passes through the half-wave plate and the second total reflection mirror in sequence, is reflected by the second total reflection mirror, passes through the half-wave plate again, and is reflected and output through the second polarization beam splitter prism.

[0022] In the laser pulse repetition frequency regulator of the present invention, the moving component includes a platform and a driving member; the first reflector group is installed on the platform; and the driving member is used to drive the platform to move in a direction perpendicular to the wave propagation direction of the incident light.

[0023] In the laser pulse repetition frequency regulator of the present invention, the first reflector group includes a first reflector and a second reflector; the first reflector and the second reflector are arranged in sequence along the propagation direction of the second polarized light.

[0024] In the laser pulse repetition frequency regulator of the present invention, the first reflector, the second reflector, the third reflector and the fourth reflector are arranged at the four vertices of a square, so that the optical path of the second polarized light emitted from the first polarization beam splitter prism to returning to the first polarization beam splitter prism is a square.

[0025] In a second aspect, the present invention further provides a solid pulse laser, comprising any of the above-mentioned laser pulse repetition frequency regulators and a laser; the laser pulse repetition frequency regulator is used to adjust the frequency of the laser emitted by the laser.

[0026] The technical solution adopted by the present invention can achieve the following beneficial effects:

[0027] The present invention mainly provides a laser pulse repetition frequency regulator, which is based on separating incident light into a first polarized light and a second polarized light by cooperating with a first half-wave plate and a first polarization beam splitter prism, wherein the first polarized light is output, and the second polarized light returns to the first polarization beam splitter prism after passing through a first reflector group, a second reflector group and a second half-wave plate in sequence, and is separated again, and the time for the second polarized light to return to the first polarization beam splitter prism, if the return time is greater than the period of the incident light, that is, greater than the pulse period of the incident light, can change the pulse frequency of the first polarized light, and by adjusting the position of the first reflector group by a moving component, pulsed light with different pulse repetition frequencies, that is, the first polarized light, can be obtained, thereby realizing adjustable pulse repetition frequency; the present invention has a simple structure, low production cost, simple and fast production and manufacturing, long service life, and avoids the disadvantage of high phase noise of a conventional locked mode resonant cavity. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments, which constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions explain the present invention and do not constitute improper limitations on the present invention. In the drawings:

[0029] Figure 1 It is a structural schematic diagram of a laser pulse repetition frequency regulator of the present invention;

[0030] Figure 2 It is a schematic structural diagram of the negative dispersion compensation device of the present invention;

[0031] Figure 3 It is a structural schematic diagram of the waveform editor of the present invention;

[0032] Figure 4 is a pulse diagram of the incident light in the present invention;

[0033] Figure 5 is a pulse interval diagram of horizontally polarized light of the first polarized light and the second polarized light in the present invention;

[0034] Figure 6 It is a pulse diagram after the first polarized light is superimposed on the second polarized light in the present invention;

[0035] Figure 7 is the attenuation envelope diagram;

[0036] Figure 8 It is the rising envelope diagram;

[0037] Fig. 9 It is the pulse energy equalization envelope diagram.

[0038] Description of reference numerals:

[0039] 1. First half-wave plate; 2. First polarization beam splitter; 3. First reflector group; 31. First reflector; 32. Second reflector; 4. Moving assembly; 41. Platform; 42. Driving member; 5. Second reflector group; 51. Third reflector; 52. Fourth reflector; 6. Second half-wave plate; 7. Optical signal enhancement device; 71. Laser gain medium; 72. Pump laser; 8. Negative dispersion compensation device; 81. Second polarization beam splitter; 82. Negative dispersion compensation assembly; 821. Quarter wave plate; 822. Transmission compression grating; 823. First total reflection mirror; 83. Polarization state adjustment assembly; 831. Half-wave plate; 832. Second total reflection mirror; 9. Waveform editor; 91. Acousto-optic modulator; 911. Acousto-optic medium; 912. Piezoelectric transducer; 92. Arbitrary waveform generator. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the specific embodiments of the present invention and the corresponding drawings. In the description of the present invention, it should be noted that the term "or" is usually used in the sense of including "and / or", unless the content clearly indicates otherwise.

[0041] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or a magnetic connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. In addition, in the description of this application, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance. In the description of the present invention, the meaning of "multiple" is at least two, such as two, three or more, etc., unless otherwise clearly and specifically limited.

[0042] Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0043] In order to solve the problems existing in the prior art, the embodiments of the present application provide a laser pulse repetition frequency regulator and a solid-state pulse laser. Example 1

[0044] This embodiment provides a laser pulse repetition frequency regulator, such as Figure 1 As shown, it includes: a first half-wave plate 1, a first polarization beam splitter prism 2, a first reflector group 3, a moving component 4, a second reflector group 5 and a second half-wave plate 6; the first half-wave plate 1 and the first polarization beam splitter prism 2 are arranged in sequence along the wave transmission direction of the incident light A; the first polarization beam splitter prism 2 is used to separate the incident light A into a first polarization light B and a second polarization light C; the first polarization light B is the output light; the second polarization light C passes through the first reflector group 3, the second reflector group 5 and the second half-wave plate 6 in sequence and then returns to the first polarization beam splitter prism 2 for separation again, and the separation direction is along the direction of the first polarization light B and the second polarization light C; the moving component 4 is at least used to drive the first reflector group 3 to move, so as to change the time from the second polarization light C being emitted from the first polarization beam splitter prism 2 to returning to the first polarization beam splitter prism 2.

[0045] The invention discloses a laser pulse repetition frequency regulator, which is based on separating incident light A into first polarized light B and second polarized light C by cooperating with a first half-wave plate 1 and a first polarized beam splitter prism 2, wherein the first polarized light B is output, and the second polarized light C returns to the first polarized beam splitter prism 2 after passing through a first reflector group 3, a second reflector group 5 and a second half-wave plate 6 in sequence, and is separated again. If the time for the second polarized light C to return to the first polarized beam splitter prism 2 is greater than the period of the incident light A, that is, greater than the pulse period of the incident light A, the pulse frequency of the output light can be changed, and the position of the first reflector group 3 is adjusted by a moving component 4, so that output light with different pulse repetition frequencies can be obtained, thereby realizing adjustable pulse repetition frequency. The invention has a simple structure, low production cost, simple and fast production and manufacturing, long service life, and avoids the disadvantage of high phase noise of a conventional mode-locked resonant cavity.

[0046] In some preferred embodiments, the propagation directions of the first polarized light B and the second polarized light C are perpendicular to each other, and the light intensity ratio is 1:1 to achieve the equality of pulse energy; the incident light A is parallel to the first polarized light B.

[0047] In some preferred embodiments, Figure 1 As shown, it also includes an optical signal enhancement device 7; the optical signal enhancement device 7 is used to enhance the signal of the second polarized light C; due to the splitting characteristics of the first polarization beam splitter prism 2, when the second polarized light C entering the optical path loop formed by the first reflector group 3, the second reflector group 5, the second half-wave plate 6 and the first polarization beam splitter prism 2 returns, the horizontal polarization splitting intensity under the action of the second half-wave plate 6 is 50% of the previous pulse. When the number of cycles increases, the pulse intensity will continue to decay until the detector cannot detect it. The pulse signal is amplified by the optical signal enhancement device 7 to ensure the intensity of the first polarized light B signal light.

[0048] Preferably, the optical signal enhancement device 7 includes a laser gain medium 71 and a pump laser 72; the laser gain medium 71 is arranged between the first reflector group 3 and the second reflector group 5; the pump laser 72 can emit pump light to the laser gain medium 71 through the second reflector group 5; the pump laser 72 transmits the pump light through the second reflector group 5 into the laser gain medium 71, and amplifies the signal light entering the laser gain medium 71.

[0049] Preferably, the second reflector group 5 includes a third reflector 51 and a fourth reflector 52; the third reflector 51 and the fourth reflector 52 are arranged in sequence along the light propagation direction; the pump laser emitted by the pump laser 72 enters the laser gain medium 71 after being transmitted through the third reflector 51; specifically, the third reflector 51 is a pump reflector so that the laser reflection is opposite to the pump laser transmission.

[0050] In the process of amplifying the pulse train, the pulse that first enters the laser gain medium 71 is subjected to energy extraction, which consumes the number of upper energy level particles and performs pulse saturation amplification, resulting in insufficient extraction of subsequent pulses, thereby further widening the pulse energy ratio and causing the pulse train energy to decay exponentially. In actual applications, a specific ratio of pulse energy amplitudes is usually required. To prevent this phenomenon, the laser pulse repetition frequency regulator of the present invention also includes a waveform editor 9; the waveform editor 9 is used to perform waveform editing on the second polarized light C, and the waveform editor 9 is used to generate an exponentially growing shape. The energy-extracted pulses are attenuated first, so that the energy of the light pulses that are later in the sequence gradually increases, thereby offsetting the excessive extraction of pulse energy by the first pulse.

[0051] Preferably, if Figure 3 As shown, the waveform editor 9 includes an acousto-optic modulator 91 and an arbitrary waveform generator 92; the arbitrary waveform generator 92 is used to control the acousto-optic modulator 91 to perform waveform editing on the second polarized light C. As long as the active optical loop is not limited by the influence of gain saturation, it has the characteristic of forming the required burst amplitude envelope shape; by actively modulating the optical signal enhancement device 7 or the acousto-optic modulator 91, an amplitude envelope of an arbitrary shape with a single pulse resolution can be obtained; as shown in FIG. Figure 7-Figure 9 As shown, the decay envelope, rise envelope and pulse energy equalization envelope can meet different industrial and scientific needs.

[0052] Preferably, the acousto-optic modulator 91 includes an acousto-optic medium 911 and a piezoelectric transducer 912; the piezoelectric transducer 912 can generate ultrasonic waves of the same frequency based on the carrier frequency emitted by the arbitrary waveform generator 92; the acousto-optic medium 911 receives ultrasonic waves to change the propagation direction of the second polarized light C.

[0053] Preferably, the waveform editor 9 is arranged between the second reflection mirror group 5 and the second half-wave plate 6 .

[0054] In some preferred embodiments, Figure 1 and Figure 2 As shown, it also includes a negative dispersion compensation device 8; the negative dispersion compensation device 8 is used to perform negative dispersion compensation on the second polarized light C; based on the negative dispersion compensation device 8, the difference between pulses is compensated, so that each pulse after compression between the pulse envelopes is consistent, thereby ensuring that zero dispersion is introduced in each cycle of the pulse light, that is, the negative dispersion amount provided by the negative dispersion compensation device 8 is the sum of the positive dispersion amounts introduced by the optical elements passed through in the loop of the second polarized light C.

[0055] Preferably, if Figure 2As shown, the negative dispersion compensation device 8 includes a second polarization beam splitter prism 81, a negative dispersion compensation component 82 and a polarization state adjustment component 83; the second polarization beam splitter prism 81 is used to reflect the second polarized light C to the negative dispersion compensation component 82; the negative dispersion compensation component 82 is used to perform negative dispersion compensation on the second polarized light C and adjust the polarization state so that the second polarized light C enters the polarization state adjustment component 83 after being transmitted through the second polarization beam splitter prism 81; the polarization state adjustment component 83 is used to adjust the polarization state of the transmitted light of the second polarization beam splitter prism 81 and reflect it from the second polarization beam splitter prism 81 for output; based on this, not only negative dispersion compensation can be achieved, but also the propagation direction of the light is not changed.

[0056] Preferably, the direction of the light reflected and output by the second polarization beam splitter prism 81 is the same as the direction in which the second polarized light C enters the second polarization beam splitter prism 81 .

[0057] Preferably, the negative dispersion compensation component 82 includes a quarter wave plate 821, a transmission compression grating 822 and a first total reflection mirror 823. The second polarized light C passes through the quarter wave plate 821, the transmission compression grating 822 and the first total reflection mirror 823 in sequence, is reflected by the first total reflection mirror 823 and passes through the transmission compression grating 822 and the quarter wave plate 821 again. At this time, the light emitted by the quarter wave plate 821 is horizontally polarized light. The horizontally polarized light enters the second polarization splitter prism 81 and is transmitted into the compression grating 822. The output light of the compression grating 822 is perpendicular to the first total reflection mirror 823.

[0058] Preferably, the polarization state adjustment component 83 includes a half-wave plate 831 and a second total reflection mirror 823; the transmitted light through the second polarization beam splitter prism 81 passes through the half-wave plate 831 and the second total reflection mirror 823 in sequence, is reflected by the second total reflection mirror 823, passes through the half-wave plate 831 again, and is reflected and output through the second polarization beam splitter prism 81; the transmitted light of the second polarization beam splitter prism 81 is horizontally polarized light, and its polarization state changes to vertically polarized light after passing through the half-wave plate 831. The vertically polarized light is incident on the second total reflection mirror 823 and then reflected to the second polarization beam splitter prism 81, and then is reflected by the second polarization beam splitter prism 81 and output.

[0059] In some preferred embodiments, Figure 1 As shown, the moving assembly 4 includes a platform 41 and a driving member 42; the first reflector group 3 is mounted on the platform 41; the driving member 42 is used to drive the platform 41 to move along a direction perpendicular to the propagation direction of the incident light A, as shown in FIG. Figure 1 Middle D direction.

[0060] In some preferred embodiments, Figure 1As shown, the first reflector group 3 includes a first reflector 31 and a second reflector 32; the first reflector 31 and the second reflector 32 are sequentially arranged along the propagation direction of the second polarized light C. Further preferably, 11A. the first reflector 31, the second reflector 32, the third reflector 51 and the fourth reflector 52 are arranged at four vertices of a square, so that the optical path of the second polarized light C emitted from the first polarization beam splitter prism 2 to the first polarization beam splitter prism 2 is a square.

[0061] The working process of a laser pulse repetition frequency regulator of the present invention is described below by using an example:

[0062] The incident light A is a polarized pulse light with a low repetition frequency. The pulse light passes through the first half-wave plate 1 and is incident on the first polarization beam splitter prism 2. The first half-wave plate 1 is rotated so that the intensity ratio of the second polarization light C and the first polarization light B separated by the first polarization beam splitter prism 2 is 1:1.

[0063] The reflected second polarized light C is reflected by the first reflector 31 and the second reflector 32 into the laser gain medium 71, and the pump laser 72 passes the pump light through the second reflector 32 into the laser gain medium 71 to amplify the optical signal. The amplified optical signal is reflected by the third reflector 51 into the negative dispersion compensation device 8, and the negative dispersion provided by the negative dispersion compensation device 8 is adjusted to compensate for the positive dispersion additionally introduced from the first polarization beam splitter prism 2, the first reflector group 3, the second reflector group 5, the second half-wave plate 6, the optical signal enhancement device 7, and the waveform editor 9. Then, the second polarized light C is incident on the fourth reflector 52, and the waveform editor 9 continues to edit the waveform of the pulse train of the optical signal. The edited pulse light is incident on the first polarization beam splitter prism 2 through the second half-wave plate 6, and the first polarization beam splitter prism 2 performs 1:1 beam splitting on the second polarized light C, wherein the horizontal polarized light is directly output, and the vertical polarized light continues to be reflected by the first reflector 31 into the loop.

[0064] The horizontal polarized light obtained by the separation of the second polarized light C and the pulse of the horizontal polarized light initially output by the incident light A form an output containing two pulses, and the vertical polarized light obtained by the separation of the second polarized light C continues to enter the loop for the next cycle. After the second round trip, a light containing 3 pulse sequences will be formed. After N round trips, N+1 pulse sequences will be formed at the output end of the active optical fiber loop, that is, the horizontal light output side of the first polarization beam splitter prism 2.

[0065] The time interval T1 of the first pulse of the first polarized light B is determined by the pulse period T0 of the initial pulse sequence of the incident light A. Figure 4 , that is, the pulse time interval, is determined by the time delay T2 between the second polarized light C entering the loop and the second pulse of the incident light A, such as Figure 5 , that is, T1=T0+T2, such as Figure 6In order to obtain an ultra-high pulse repetition frequency, the length of the loop through which the second polarized light C passes can be changed, so that the second polarized light C after the incident light A is split by the first polarization beam splitter prism 2 lags behind the light pulse output by the incident light A when it returns to the first polarization beam splitter prism 2 after going around the loop, such as the pulse time interval is less than 1ns.

[0066] Taking the incident light A as a linearly polarized light with a frequency of 40MHz and a central wavelength of 1030nm as an example, the pulse time period of the incident light A is 25ns. In order to obtain light with a repetition frequency of 1GHz, the output pulse time period is 1ns. The second polarized light C entering the loop, that is, the vertically polarized light, should be delayed by 1ns after returning to the first polarization beam splitter prism 2 after a cycle than the second pulse signal of the incident light A, that is, the time for the second polarized light C to circulate in the loop is 26ns. From the frequency f=c / L'=1 / T, where c is the speed of light in a vacuum, 3*10 8 m / s, L' is the optical path, L'=L1+nL2, where n is the refractive index of the medium, L1 is the length of the spatial optical path, and L2 is the length of the transmitted optical element, which is about 0.08 meters. The refractive index n=1.5 is used here for estimation. The optical path required for light to circulate in the loop for 26ns is 7.8m, so the spatial optical path length is L1=7.8-0.12=7.68m. The frequency deviation caused by the deviation between the theoretical estimated length and the actual length can be compensated by the moving component 4, such as by adjusting the driving member 42 to drive the first reflector group 3 to move in the horizontal direction, thereby adjusting the length L1 of the spatial optical path. In this example, the pump laser used to compensate for the signal light loss is a 969nm diode, and the laser gain medium is a Yb:YAG crystal. In this example, the negative dispersion compensation device 8 provides -800fs 2 The amount of second-order dispersion. Example 2

[0067] This embodiment provides a solid pulse laser, which includes the laser pulse repetition frequency regulator and the laser in the above-mentioned embodiment 1; the laser pulse repetition frequency regulator is used to adjust the frequency of the laser emitted by the laser; the laser is a solid laser. Compared with the fiber laser, the solid space structure ensures that no additional high-order dispersion is introduced even at large pulse energy, thereby ensuring the compressibility of the pulse, while the high pulse energy of the fiber laser is prone to produce incompressible high-order dispersion.

[0068] The embodiments of the present invention are described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific implementation modes, which are merely illustrative rather than restrictive. Under the guidance of the present invention, ordinary technicians in this field can also make many forms without departing from the scope of protection of the present invention and the claims, all of which are within the protection of the present invention.

Claims

1. A laser pulse repetition frequency regulator, characterized in that: include: A first half-wave plate, a first polarization beam splitter, a first reflector group, a moving component, a second reflector group, a second half-wave plate and a negative dispersion compensation device; The first half-wave plate and the first polarization beam splitter prism are arranged in sequence along the wave propagation direction of the incident light; The first polarization beam splitter prism is used to separate the incident light into a first polarized light and a second polarized light; The first polarized light is output light; The second polarized light returns to the first polarization beam splitter prism and is separated again after passing through the first reflector group, the second reflector group and the second half-wave plate in sequence, and the separation direction is along the direction of the first polarized light and the second polarized light; The moving component is at least used to drive the first reflector group to move, so as to change the time from when the second polarized light is emitted from the first polarization beam splitter prism to when it returns to the first polarization beam splitter prism; The negative dispersion compensation device is used to perform negative dispersion compensation on the second polarized light; The negative dispersion compensation device comprises a second polarization beam splitter prism, a negative dispersion compensation component and a polarization state adjustment component; The second polarization beam splitter prism is used to reflect the second polarized light to the negative dispersion compensation component; The negative dispersion compensation component is used to perform negative dispersion compensation on the second polarized light and adjust the polarization state so that the second polarized light can enter the polarization state adjustment component after being transmitted through the second polarization beam splitter prism; The polarization state adjustment component is used to adjust the polarization state of the transmitted light of the second polarization beam splitter prism and then reflect the light from the second polarization beam splitter prism and output it.

2. The laser pulse repetition frequency regulator according to claim 1, characterized in that: Also included is an optical signal enhancement device; The optical signal enhancement device is used to enhance the signal of the second polarized light.

3. The laser pulse repetition frequency regulator according to claim 2, characterized in that: The optical signal enhancement device includes a laser gain medium and a pump laser; The laser gain medium is arranged between the first reflector group and the second reflector group; The pump laser can emit pump light to the laser gain medium through the second reflection mirror group.

4. The laser pulse repetition frequency regulator according to claim 3, characterized in that: The second reflector group includes a third reflector and a fourth reflector; The third reflector and the fourth reflector are arranged in sequence along the light propagation direction; The pump laser enters the laser gain medium after being transmitted through the third reflecting mirror.

5. The laser pulse repetition frequency regulator according to claim 1 or 3, characterized in that: It also includes a waveform editor; the waveform editor is used to edit the waveform of the second polarized light.

6. The laser pulse repetition frequency regulator according to claim 5, characterized in that: The waveform editor includes an acousto-optic modulator and an arbitrary waveform generator; The arbitrary waveform generator is used to control the acousto-optic modulator to perform waveform editing on the second polarized light.

7. The laser pulse repetition frequency regulator according to claim 1, characterized in that: The negative dispersion compensation component includes a quarter wave plate, a transmission compression grating and a first total reflection mirror. The second polarized light passes through the quarter wave plate, the transmission compression grating and the first total reflection mirror in sequence, is reflected by the first total reflection mirror, passes through the transmission compression grating and the quarter wave plate again, and then enters the second polarization splitter prism.

8. The laser pulse repetition frequency regulator according to claim 1, characterized in that: The polarization state adjustment component includes a half-wave plate and a second total reflection mirror; the transmitted light through the second polarization beam splitter prism passes through the half-wave plate and the second total reflection mirror in sequence, is reflected by the second total reflection mirror, passes through the half-wave plate again, and is reflected and output through the second polarization beam splitter prism.

9. The laser pulse repetition frequency regulator according to claim 1, characterized in that: The mobile assembly includes a platform and a driving member; The first reflector group is installed on the platform; The driving member is used to drive the platform to move along a direction perpendicular to the wave transmission direction of the incident light.

10. The laser pulse repetition frequency regulator according to claim 1, characterized in that: The first reflector group includes a first reflector and a second reflector; The first reflector and the second reflector are sequentially arranged along a propagation direction of the second polarized light.

11. A solid pulse laser, characterized in that: It comprises the laser pulse repetition frequency regulator and the laser as described in any one of claims 1 to 10 above; the laser pulse repetition frequency regulator is used to adjust the frequency of the laser emitted by the laser.

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