CN217934552U - Nanosecond-picosecond combined laser - Google Patents
Nanosecond-picosecond combined laser Download PDFInfo
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- CN217934552U CN217934552U CN202221785452.1U CN202221785452U CN217934552U CN 217934552 U CN217934552 U CN 217934552U CN 202221785452 U CN202221785452 U CN 202221785452U CN 217934552 U CN217934552 U CN 217934552U
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Abstract
The utility model relates to a laser instrument field especially relates to nanosecond-picosecond combination laser instrument, including transferring Q resonant cavity passively, enlarge module, second half wave plate, first polarization beam splitter, SBS pulse compression module, time delay module and third polarization beam splitter, transfer Q resonant cavity passively, enlarge module, second half wave plate, first polarization beam splitter, SBS pulse compression module and third polarization beam splitter's central point parallel and level, first polarization beam splitter, time delay module and third polarization beam splitter center are relative; the passively Q-switched resonant cavity generates nanosecond linearly polarized seed light and then enters the amplification module for power amplification, the amplified seed light passes through the second half wave plate and is divided into first seed light and second seed light in the first polarization beam splitter prism, the first seed light is converted into picosecond light through the SBS pulse compression module, and the second seed light is combined with the picosecond light in the third polarization beam splitter prism through the time delay module. The utility model discloses simple structure and stability.
Description
Technical Field
The utility model relates to a laser instrument field especially relates to nanosecond-picosecond combination laser instrument.
Background
With the development of science and technology, the CCD plays an irreplaceable role in the aspects of infrared guidance, high-altitude reconnaissance, precise positioning and the like by virtue of the advantages of high photon conversion efficiency, wide spectral response, low cost, small size and the like, and the CCD is extremely easy to be interfered and damaged by a laser weapon as a core component of a photoelectric system, so that the CCD becomes a primary attack target in photoelectric countermeasure.
From the 90 s in the 20 th century, researchers used various irradiation sources to perform damage experiments on photodetectors, and laser is made up by virtue of the advantages of narrow pulse width, high power and the like, and gradually becomes a hot point of research. After that, researchers combine different types of lasers into a new laser source to perform damage experiments on the target materials such as monocrystalline silicon, metal aluminum and the like, and the results show that the damage rate of the combined laser to the target materials is obviously improved, particularly the damage effect of the laser formed by combining pulse lasers is more obvious, and the monocrystalline silicon and the metal aluminum are just the components of the CCD, so that the combined laser can generate a stronger induced breakdown effect on the CCD. A good combination laser is necessary.
The laser combination can be the output combination of two lasers with different pulse widths, but the synergy requirement between the two lasers is very high, and the two lasers are difficult to output simultaneously. In the pulse compression technology, SBS has the advantages of simple structure, phase conjugation, high load, and the like, and is the most commonly used pulse compression technology.
SUMMERY OF THE UTILITY MODEL
To the problem that two lasers are difficult to control the optical distance for traditional combination laser application, the utility model discloses a laser utilizes pulse compression's method, produces the laser of different pulsewidths, and the method that control optical distance utilized polarization to close the bundle couples two bundles of laser to be in the same place, output combination laser. The problems that the optical path is difficult to control and the coupling effect of two beams of laser is poor are solved.
In order to achieve the above purpose, the technical solution of the present invention is realized as follows: the nanosecond-picosecond combined laser is characterized by comprising a passive Q-switching resonant cavity, an amplification module, a second half wave plate, a first polarization beam splitter prism, an SBS pulse compression module, a time delay module and a third polarization beam splitter prism, wherein the central points of the passive Q-switching resonant cavity, the amplification module, the second half wave plate, the first polarization beam splitter prism, the SBS pulse compression module and the third polarization beam splitter prism are arranged on the same horizontal line, and the central points of the first polarization beam splitter prism, the time delay module and the third polarization beam splitter prism are arranged on the same horizontal line; the passive Q-switched resonant cavity generates nanosecond linear polarization seed light, the seed light enters the amplification module to be subjected to power amplification, the amplified seed light passes through the second half wave plate and is divided into first seed light and second seed light in the first polarization beam splitting prism, the first seed light enters the SBS pulse compression module to generate picosecond light, the second seed light enters the time delay module, and the second seed light and the picosecond light are combined in the third polarization beam splitting prism.
The passive Q-switched resonant cavity comprises a first 0-degree full-reflecting mirror, a partial reflecting mirror, a first polarizer, a first quarter-wave plate, a passive Q-switched crystal, a first LD pump measuring module, a second quarter-wave plate and an output mirror which are sequentially arranged, wherein the central points of the first 0-degree full-reflecting mirror, the partial reflecting mirror, the first polarizer, the first quarter-wave plate, the passive Q-switched crystal, the first LD side pump module, the second quarter-wave plate and the output mirror are arranged on the same horizontal line, and seed light is output by the output mirror and enters the amplifying module.
A first optical isolator is arranged between the amplifying module and the second half-wave plate, and the central points of the amplifying module, the first optical isolator and the second half-wave plate are arranged on the same horizontal line.
The first optical isolator comprises a second polarizer, a Faraday optical rotator, a first one-half wave plate and a third polarizer which are sequentially arranged, and the central points of the second polarizer, the Faraday optical rotator, the first one-half wave plate and the third polarizer are arranged on the same horizontal line.
And a third half wave plate is arranged between the SBS pulse compression module and the third polarization beam splitter prism, and the central points of the SBS pulse compression module, the third half wave plate and the third polarization beam splitter prism are arranged on the same horizontal line.
The SBS pulse compression module comprises a second polarization beam splitter prism, a third quarter wave plate, a first positive lens and a Brillouin medium pool which are sequentially arranged, and the central points of the second polarization beam splitter prism, the third quarter wave plate, the first positive lens and the Brillouin medium pool are arranged on the same horizontal line.
The Brillouin medium pool is provided with a first window mirror with the thickness d 1 The first window mirror and the center point of the first positive lens are arranged on the same horizontal line.
Adopt above-mentioned structure the utility model discloses simple structure, stability are good, can be used to fields such as photoelectricity confrontation, material test, the utility model discloses utilize first polarization beam splitter prism to throw horizontal polarized light, handle the nanosecond laser of transferring Q resonant cavity output passively to the characteristic of vertical polarization light reflection to turn into two bundles of laser with a branch of laser, solved the problem that two lasers are difficult to coordinated control, simplified the device structure. The utility model discloses a SBS pulse compressor compresses the formation picosecond laser to nanosecond laser, simple structure and have higher compression efficiency, simultaneously, the utility model discloses utilize third polarization beam splitter prism to make two bundles of laser coupling be a branch of laser through the polarization group bundle method, compensatied the shortcoming that two laser light journey are difficult to calculate, simplify the structure of laser instrument, the combination effect is better, the laser that adopts the formation simultaneously is formed by the pulse laser combination, this laser is faster to the damage speed of target, the destruction effect is more visible showing, the problem that laser weapon damage speed is low in the photoelectric countermeasure has been solved, the deep research of the core device CCD damage mechanism in the photoelectric system has been promoted greatly.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.
Fig. 1 is a schematic structural diagram of the present invention.
Fig. 2 is a schematic structural diagram of the passive Q-switched resonator according to the present invention.
Fig. 3 is a schematic diagram of the beam splitting of the present invention.
Fig. 4 is a schematic structural diagram of an SBS pulse compression module.
Fig. 5 is a schematic diagram of optical path calculation of the delay module.
In the figure, 1 is a passive Q-switched resonant cavity, 2 is a power amplification module, 3 is a first optical isolator, 4 is a second half-wave plate, 5 is a first polarization splitting prism, 6 is an SBS pulse compression module, 7 is a third half-wave plate, 8 is a time delay module, 9 is a third polarization splitting prism, 1-1 is a first 0-degree total reflection mirror, 1-2 is a first partial reflection mirror, 1-3 is a first polarizer, 1-4 is a first quarter-wave plate, 1-5 is a passive Q-switched crystal, 1-6 is a first LD side pump module, 1-7 is a second quarter-wave plate, 1-8 is an output mirror, 6-1 is a second polarization splitting prism, 6-2 is a third quarter-wave plate, 6-3 is a first positive lens, and 6-4 is a Brillouin medium pool.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without any creative effort belong to the protection scope of the present invention.
As shown in fig. 1, the nanosecond-picosecond combination laser includes a passive Q-switched resonant cavity 1, an amplification module 2, a second half-wave plate 4, a first polarization beam splitter prism 5, an SBS pulse compression module 6, a time delay module 8, and a third polarization beam splitter prism 9, where the centers of the passive Q-switched resonant cavity 1, the amplification module 2, the second half-wave plate 4, the first polarization beam splitter prism 5, the SBS pulse compression module 6, and the third polarization beam splitter prism 9 are disposed on the same horizontal line, and the centers of the first polarization beam splitter prism 5, the time delay module 8, and the third polarization beam splitter prism 9 are opposite.
The passive Q-switched resonator 1 mainly functions to generate single longitudinal mode linearly polarized seed light, and as shown in fig. 2, the passive Q-switched resonator 1 includes a first 0 ° total reflection mirror 1-1, a partial reflection mirror 1-2, a first polarizer 1-3, a first quarter wave plate 1-4, a passive Q-switched crystal 1-5, a first LD measurement pump module 1-6, a second quarter wave plate 1-7, and an output mirror 1-8, which are sequentially disposed, and central points of the first 0 ° total reflection mirror 1-1, the partial reflection mirror 1-2, the first polarizer 1-3, the first quarter wave plate 1-4, the passive Q-switched crystal 1-5, the first LD side pump module 1-6, the second quarter wave plate 1-7, and the output mirror 1-8 are disposed on the same horizontal line. The passive Q-switched resonant cavity 1 utilizes a first 0-degree total reflection mirror 1-1 and an output mirror 1-8 to form a resonant cavity, the passive Q-switched resonant cavity 1 is in a high-loss state through the saturable absorption characteristic of a passive Q-switched crystal 1-5, energy is continuously accumulated due to population inversion in the passive Q-switched resonant cavity 1, when the energy is accumulated to a certain degree, the transmittance of the passive Q-switched crystal 1-5 is suddenly increased, laser in the passive Q-switched resonant cavity 1 continuously oscillates in the resonant cavity and continuously extracts upper energy level particles accumulated by an LD side pump module 1-6, and the laser is rapidly amplified in the oscillation process to form giant pulses. Laser in the passive Q-switched resonant cavity 1 oscillates on a first 0-degree reflector 1-1, a first partial reflector 1-2 and an output mirror 1-8 to form three-surface resonance, a first polarizer 1-3 carries out polarization treatment on the laser, and finally nanosecond linear polarization seed light is output on the output mirror 1-8 and is single longitudinal mode light. Seed light passes through amplification module 2 and first optical isolator 3 in proper order after being exported by output mirror 1-8, amplification module 2's main effect is for carrying out power amplification to seed light, first optical isolator 3's main effect is for guaranteeing that seed light is along unidirectional transmission, avoid reverse transmission light to damage amplification module 2, this first optical isolator 3 is including the second polarizer, the Faraday optical rotator, first one-half wave plate and the third polarizer that set up once, the central point setting of second polarizer, the Faraday optical rotator, first one-half wave plate, the third polarizer is on same water flat line.
As shown in fig. 3, the power-amplified seed light sequentially passes through the second half wave plate 4 and the first polarization splitting prism 5, wherein the second half wave plate 4 can perform phase retardation on the incident nanosecond linearly polarized seed light to change the polarization direction thereof, so that the nanosecond linearly polarized seed light is changed into oblique polarized seed light, and the polarization rotation angle of the nanosecond linearly polarized seed light is controlled to be adjustable within 0 ° to 45 ° by the phase retardation of the second half wave plate 4. The characteristics of the first polarization beam splitter prism 5 for projecting horizontal polarized light and reflecting vertical polarized light are utilized to divide the oblique polarized seed light into the first seed light and the second seed light, so that the problem that two lasers are difficult to coordinate and control is solved, and the structure of the device is simplified. The first seed light is horizontally polarized light, the second seed light is vertically polarized light, and the energy ratio of the first seed light to the second seed light is determined by the angle of rotation of the polarization direction. The first seed light is transmitted by the first polarization beam splitter prism 5 and then enters the SBS pulse compression module 6 to generate picosecond light, and the second seed light enters the time delay module 8.
As shown in fig. 4, the SBS pulse compression module 6 includes a second polarization beam splitter prism 6-1, a third quarter wave plate 6-2, a first positive lens 6-3, a brillouin medium pool 6-4, and a second polarization beam splitter prism 6-1, a third quarter wave plate 6-2, a first positive lens 6-3, and a brillouin medium pool 6-4, which are sequentially disposedThe central points of the vibration beam splitter prism 6-1, the third quarter wave plate 6-2, the first positive lens 6-3 and the Brillouin medium pool 6-4 are arranged on the same horizontal line. Wherein, as shown in fig. 5, the brillouin medium pool 6-4 is provided with a first window mirror with a thickness d 1 The central points of the first window mirror and the first positive lens 6-3 are arranged on the same horizontal line. The focal length f of the first positive lens 6-3 should satisfy the following constraint:
L+n 1 d 1 +D 4 ≤f<L+n 1 d 1 +D 4 +L 1
wherein n is 1 Is the refractive index of the lens, D 4 L is the distance between the center of the first positive lens and the center of the first window mirror, L is the optimal interaction distance of the stimulated Brillouin scattering, and L = c τ p /2n 2 C is the speed of light in vacuum, τ p Is the pulse width of the first sub-light, L 1 Is the length of the Brillouin medium pool 6-4, and L<L 1 ，n 2 Is the brillouin medium refractive index. After entering the SBS pulse compression module 6, the first seed light is firstly separated into circular polarization picosecond light and circular polarization seed light under the action of the second polarization beam splitter prism 6-1 and the third quarter wave plate 6-2, the first positive lens 6-3 mainly acts on improving the power density of the circular polarization picosecond light and the circular polarization seed light, and as the power density of the circular polarization picosecond light and the circular polarization seed light is improved, an electrostrictive effect is generated at the focus of the first positive lens 6-3, so that a phonon field is excited to generate the stokes seed light. The stokes seed light enters the Brillouin medium pool 6-4 through the first positive lens 6-3, the SBS organic medium is contained in the Brillouin medium pool 6-4, and the Brillouin medium pool 6-4 mainly acts to generate stimulated Brillouin scattering to generate backward stokes seed light. The backward stokes seed light is output by the Brillouin medium pool 6-4, enters the third quarter-wave plate 6-2 through the first positive lens 6-3 to become vertically polarized stokes light, and is reflected at the second polarization splitting prism 6-1. The stokes light is output by the second polarization beam splitter prism 6-1 and then enters the third polarization beam splitter prism 9 through the third half wave plate 7.
The time delay module 8 into which the second seed light enters is composed of three 45-degree reflecting mirrors, and the main function of the time delay module 8 is to compensate the first seed lightThe optical path difference between the two sub-lights and the first sub-light makes the pulse peak value of the first sub-light and the second sub-light reach the third polarization beam splitter prism 9 at the same time, wherein the optical path L of the time delay module t The following constraints should be satisfied:
L t ＝D 1 +n 1 (d 2 +d 5 )+2L p +D 6 +D 7 -D 5
wherein D 1 Is the distance between the first polarization beam splitter prism 5 and the second polarization beam splitter prism 6-1, D 5 Is the distance between the first polarization beam splitter prism 5 and the time delay module 8, D 6 Is the distance between the third polarization beam splitter prism 6-1 and the third half wave plate 7, D 7 Is the distance between the third half-wave plate 7 and the third polarization beam splitter prism 9, d 2 Is the thickness of the second polarizing beam splitter prism 6-1, d 5 Is the thickness, L, of the third half wave plate 7 p Is the optical path taken by the first seed light in the SBS pulse compressor, and L p ＝D 2 +n 1 (d 1 +d 3 +d 4 )+D 3 +D 4 ，D 2 Is the distance between the second polarization beam splitter prism 6-1 and the third quarter wave plate 6-2, D 3 Is the third quarter-wave plate 6-2 and the first positive lens 6-3,D 4 Is the distance between the first positive lens 6-3 and the Brillouin medium pool 6-4, d 3 Is the thickness of the third quarter-wave plate 6-2, d 4 Is the thickness of the first positive lens 6-3. The second seed light enters the third polarization beam splitter prism 9 after being processed by the time delay module 8, the first seed light and the second seed light are coupled and output between the nanosecond light and the picosecond light in the third polarization beam splitter prism 9 by using a polarization beam combination method to form output laser, the defect that the optical paths of two lasers are difficult to calculate is overcome, and the structure of the lasers is simplified. Meanwhile, the first seed light and the second seed light are pulse lasers, and the output lasers are formed by combining the pulse lasers, the laser has higher damage rate to the target material, the damage effect is more obvious, the problem of low damage rate of a laser weapon in photoelectric countermeasure is solved, and the deep research on the damage mechanism of a core device CCD in a photoelectric system is greatly promoted.
The above description is only a preferred embodiment of the present invention, and should not be taken as limiting the invention, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (7)
1. The nanosecond-picosecond combined laser is characterized by comprising a passive Q-switched resonant cavity (1), an amplification module (2), a second half wave plate (4), a first polarization beam splitter prism (5), an SBS pulse compression module (6), a time delay module (8) and a third polarization beam splitter prism (9), wherein the central points of the passive Q-switched resonant cavity (1), the amplification module (2), the second half wave plate (4), the first polarization beam splitter prism (5), the SBS pulse compression module (6) and the third polarization beam splitter prism (9) are arranged on the same horizontal line, and the centers of the first polarization beam splitter prism (5) and the time delay module (8) are opposite to the center of the third polarization beam splitter prism (9);
the passive Q-switched resonant cavity (1) generates nanosecond linear polarization seed light, the seed light enters the amplification module (2) to be amplified in power, the amplified seed light passes through the second half wave plate (4) and is divided into first seed light and second seed light in the first polarization splitting prism (5), the first seed light enters the SBS pulse compression module (6) to generate picosecond light, the second seed light enters the time delay module (8), and the second seed light and the picosecond light are combined in the third polarization splitting prism (9).
2. The nanosecond picosecond combination laser according to claim 1, wherein said passively Q-switched resonator (1) comprises a first 0 ° fully reflective mirror (1-1), a partial reflective mirror (1-2), a first polarizer (1-3), a first quarter wave plate (1-4), a passively Q-switched crystal (1-5), a first LD side pump module (1-6), a second quarter wave plate (1-7) and an output mirror (1-8) arranged in sequence, wherein the central points of the first 0 ° fully reflective mirror (1-1), the partial reflective mirror (1-2), the first polarizer (1-3), the first quarter wave plate (1-4), the passively Q-switched crystal (1-5), the first LD side pump module (1-6), the second quarter wave plate (1-7) and the output mirror (1-8) are arranged on the same horizontal line, and the seed light is output from the output mirror (1-8) into the amplification module (2).
3. The nanosecond-picosecond combination laser according to claim 1 or 2, wherein a first optical isolator (3) is arranged between the amplification block (2) and the second half-wave plate (4), and the central points of the amplification block (2), the first optical isolator (3) and the second half-wave plate (4) are arranged on the same horizontal line.
4. The nanosecond-picosecond combination laser according to claim 3, wherein said first optical isolator (3) comprises a second polarizer, a Faraday rotator, a first quarter-wave plate and a third polarizer arranged in this order, the central points of the second polarizer, the Faraday rotator, the first quarter-wave plate and the third polarizer being arranged on the same horizontal line.
5. The nanosecond-picosecond combination laser according to claim 1 or 4, wherein a third half wave plate (7) is arranged between the SBS pulse compression module (6) and the third polarization splitting prism (9), and the central points of the SBS pulse compression module (6), the third half wave plate (7) and the third polarization splitting prism (9) are arranged on the same horizontal line.
6. The nanosecond-picosecond combination laser according to claim 5, wherein the SBS pulse compression module (6) comprises a second polarization beam splitter prism (6-1), a third quarter wave plate (6-2), a first positive lens (6-3) and a Brillouin medium pool (6-4) which are arranged in sequence, and the central points of the second polarization beam splitter prism (6-1), the third quarter wave plate (6-2), the first positive lens (6-3) and the Brillouin medium pool (6-4) are arranged on the same horizontal line.
7. The nanosecond-picosecond combination laser according to claim 6, wherein the Brillouin dielectricThe matter pool (6-4) is provided with a first window mirror, and the thickness of the first window mirror isd 1 The central points of the first window mirror and the first positive lens (6-3) are arranged on the same horizontal line.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202221785452.1U CN217934552U (en) | 2022-07-08 | 2022-07-08 | Nanosecond-picosecond combined laser |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202221785452.1U CN217934552U (en) | 2022-07-08 | 2022-07-08 | Nanosecond-picosecond combined laser |
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| CN217934552U true CN217934552U (en) | 2022-11-29 |
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| CN202221785452.1U Active CN217934552U (en) | 2022-07-08 | 2022-07-08 | Nanosecond-picosecond combined laser |
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