CN1328625C - Method for obtaining flat-topped light beam utilizing secondary stimulated Brillouin scattering light amplitude limiting - Google Patents
Method for obtaining flat-topped light beam utilizing secondary stimulated Brillouin scattering light amplitude limiting Download PDFInfo
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- CN1328625C CN1328625C CNB2005100103598A CN200510010359A CN1328625C CN 1328625 C CN1328625 C CN 1328625C CN B2005100103598 A CNB2005100103598 A CN B2005100103598A CN 200510010359 A CN200510010359 A CN 200510010359A CN 1328625 C CN1328625 C CN 1328625C
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Abstract
The present invention relates to a method which uses stimulated Brillouin scattering light amplitude limiting twice to obtain flat-topped light beams. The method which belongs to the field of non-linear optics aims to solve the problems that a nonlinear light amplitude limiting mechanism can not be applied to the safety protection of a strong laser system due to lower damage threshold, and the existing methods for obtaining flat-topped waveforms by light amplitude limiting can not adjust the transmissivity function flexibly along with the parametric variation of light beams due to the fact that the adopted elements are designed by aiming at specific light beams. In the method of the present invention, the focal point of a first convex lens 3 falls in a first oscillation pool 4, light which is transmitted by the first convex lens 3 carries out stimulated Brillouin scattering (SBS) for the first time in the position of the focal point of the first convex lens 3, transmitted light which is output from the first oscillation pool 4 and transmitted by a second convex lens 5 carries out SBS for the second time, the focal point of the second convex lens 5 also falls in a second oscillation pool 6, and light beams output from the second oscillation pool 6 are flat-topped light beams. The method of the present invention for producing flat-topped light beams is free from the limitation of parameters such as incident light wavelength, beam quality, etc., and has the characteristics of broadband, high speed, adjustable transmissivity, etc.
Description
Technical field
The present invention relates to non-linear optical field, what be specifically related to is a kind of method of utilizing the stimulated Brillouin scattering light amplitude limit to obtain flat top beam.
Background technology
In the high power strong laser system, the output laser power density is often very high, so that to various optical materials in the laser system, for example optical crystal, lens, various optical coating cause damage, this just need carry out necessary optical security protection to laser system; In addition, laser system generally can only be operated in the scope that is lower than rated power for the sake of security, thereby makes that the work efficiency of laser system is very low.If proper to the laser system safeguard procedures, just can allow laser system be operated in higher-power state as far as possible, to improve the work efficiency of system, for this reason, the laser light limiter is one of safeguard procedures preferably.People have studied the light amplitude limit mechanism based on various nonlinear effects, for example two-photon absorption and multi-photon absorbing light amplitude limit, anti-saturated absorption light amplitude limit, nonlinear refraction light amplitude limit, nonlinear reflection light amplitude limit, diffraction light amplitude limit or the like, though above nonlinear optical limiting has some advantages such as broadband, quick and high transmission, nonlinear optical limiting mechanism can't be applied to the security protection of light laser because damage threshold is lower.
At present, domestic research light amplitude limit obtain flat top beam aspect also resting on theoretical research stage, external then made relevant product, the acquisition of flat top beam mainly concentrates on following two class methods: (1) Laser Output Beam transmission Lu Jingzhong adds various optical elements or system, as reflection or refraction anamorphic optics, holographic optical elements (HOE), binary diffractive optical element, random order photograph, array optical element etc.; (2) use special cavity resonator structure directly to obtain flat top beam, as adding variable reflectivity mirror sheet, gradual change phase place mirror, self-adaptation mirror, space-time phase modulation (PM) mirror etc. in the chamber.Above method has his own strong points, but a common shortcoming is arranged: also be subjected to the restriction of little retrofit state-of-art in the manufacturing of device at present, each device designs at specific light beam parameters, the device of making can not be regulated its transmittance function neatly with the variation of light beam parameters, so can only design different light limiting elements at the difference of laser type when realizing that with said method the light amplitude limit obtains flat top beam, cause the complicacy of implementation method, ineffective activity.
Summary of the invention
The objective of the invention is in order to solve the machine-processed security protection that can't be applied to strong laser system because damage threshold is lower of nonlinear optical limiting, and the method for existing acquisition flat top beam can't change the problem of its transmittance function of flexible with light beam parameters because of using element at specific light beam design, thereby a kind of method of utilizing the secondary stimulated Brillouin scattering light limiting amplitude to obtain flat top beam is provided, and it is based on the method that Gauss light is become flat top beam of stimulated Brillouin scattering (SBS) principle.
Secondary stimulated Brillouin scattering system of the present invention is by polaroid, quarter wave plate, first convex lens, the first vibration pond, second convex lens, second vibration pond and the laser constitution, the present invention realizes that the method that the light amplitude limit obtains flat top beam is: the p polarized light of laser instrument output is input to the input end of polaroid after polaroid transmission and output to the input end of quarter wave plate from the output terminal of polaroid, through obtaining circularly polarized light and be input in the input end of first convex lens at the output terminal of quarter wave plate behind the quarter wave plate propagation and transformation, output to the input end in the first vibration pond through the circularly polarized light of first convex lens transmission light output end from first lens, the light output end of first convex lens focuses on focus in the first vibration pond, circularly polarized light through the transmission of first convex lens focuses on focus place generation SBS effect for the first time and produces the Stokes seed light at the light output end of first convex lens, the Stokes seed light that the described first time, SBS produced obtains amplifying afterwards along former road first convex lens in the first vibration pond, be input on the polaroid behind the quarter wave plate, Stokes seed light output terminal at quarter wave plate behind the quarter wave plate propagation and transformation that the described first time, SBS produced obtains the s polarized light and is polarized sheet reflecting, and be input to the input end of second convex lens through SBS for the first time and from the transmitted light of the output terminal output in the first vibration pond, output to the input end in the second vibration pond through the transmitted light of second convex lens transmission light output end from second convex lens, the light output end of second convex lens focuses on focus in the second vibration pond, transmitted light through the transmission of second convex lens focuses on focus place generation SBS effect for the second time and produces the Stokes seed light at the light output end of second convex lens, the Stokes seed light that the described second time, SBS produced obtains amplifying afterwards along former road second convex lens in the second vibration pond, the first vibration pond, first convex lens, be input on the polaroid behind the quarter wave plate, Stokes seed light output terminal at quarter wave plate behind the quarter wave plate propagation and transformation that described second time, SBS produced obtains the s polarized light and is polarized sheet reflecting, and promptly is required flat top beam through SBS for the second time and from the transmitted light of the output terminal output in the second vibration pond.
Principle of work: the pumping light pulse (as shown in Figure 2) of laser instrument output begins to enter into the first vibration Chi Zhongshi among the present invention, be not enough to produce the SBS effect owing to pulse power is less, so shape still along the line sees through medium, transmitted pulse forward position profile and pumping light pulse waveform profile phase keep accurate Gaussian together at this moment; When the pumping light pulse power has just surpassed the SBS threshold value of the first vibration pond medium, because the generation of SBS is based on the foundation of the phonon fields of medium, its foundation must need certain relaxation time, thereby pumping light still keeps high-transmission rate, this moment transmitted pulse forward position profile and pumping light pulse waveform contour approximation, but pulse waveform is owing to small distortion takes place in the SBS effect; When the pumping light pulse power surpasses the SBS threshold value of the first vibration pond medium when a lot, stronger SBS takes place and interacts in laser pulse and Brillouin's medium, cause the pumping laser energy promptly to shift to scattered light Stokes field, the Stokes field increases rapidly, cause the pump pulse luminous energy to be exhausted rapidly, thereby suddenly descend along beginning after the transmitted pulse, stay next very steep decline, then the power owing to succeeding impulse does not reach the threshold power that produces the SBS effect, thereby pulse back edge power just maintains a near power " platform " (as shown in Figure 3); Waveform through SBS light amplitude limit output for the second time almost is a flat-top (as shown in Figure 4), have only spike just can reach the SBS threshold value in the middle of the SBS light amplitude limit for the second time, and the pumping light energy promptly shifts to scattered light Stokes field, therefore spike is eliminated, originally the power of " platform " position did not reach the threshold value of SBS, still maintain the original state, so final integral becomes a flat-top, the fluctuating at top is caused by modulation phenomenon.By theory as can be known, the gain coefficient of vibration pond medium is more little, and absorption coefficient is more little, and the energy of SBS light amplitude limit output is just high more, so, in order to improve the energy of light amplitude limit output of the present invention, in the first vibration pond, select the little Brillouin's medium of gain coefficient.In order effectively to eliminate the forward position peak power (as shown in Figure 3) that produces through after the SBS effect for the first time, in the second vibration pond, select Brillouin's medium that the SBS threshold value is little, phonon lifetime is short or gain coefficient is big for use.
The method that the present invention produces flat top beam is not subjected to incident light parameter wavelength, the isoparametric restriction of beam quality, and can regulate parameters such as the output energy of flat top beam and pulse width neatly by changing Brillouin's medium parameter in incident light parameter, lens arrangement parameter and the vibration pond, it is applicable to various laser systems, particularly strong laser system; And method is simple, and dirigibility is strong, has broadband, fast and characteristics such as transmittance is adjustable.The flat top beam that the present invention produces can be applicable to Materialbearbeitung mit Laserlicht (as laser bonding and laser drill), laser clinical medicine (as excimer laser treatment myopia), laser lithography, the detection array laser radar, laser scanning, aspects such as optical information processing, storage and record have a wide range of applications.
Description of drawings
Fig. 1 is the structural representation of system of the present invention, Fig. 2 is the pumping light waveform of laser instrument 7 outputs, Fig. 3 is through the transmitted light waveform of exporting from the first vibration pond 4 after the SBS effect first time, and Fig. 4 is the waveform through the transmitted light of exporting from the second vibration pond 6 after the SBS effect for the second time.
Embodiment
Embodiment one: this embodiment is described in conjunction with Fig. 1, the secondary stimulated Brillouin scattering system of this embodiment is by polaroid 1, quarter wave plate 2, first convex lens 3, the first vibration pond 4, second convex lens 5, the second vibration pond 6 and laser instrument 7 are formed, this embodiment realizes that the method that the light amplitude limit obtains flat top beam is: the p polarized light of laser instrument 7 outputs is input to the input end of polaroid 1 after polaroid 1 transmission and output to the input end of quarter wave plate 2 from the output terminal of polaroid 1, behind quarter wave plate 2 propagation and transformations, obtain circularly polarized light and be input in the input end of first convex lens 3 at the output terminal of quarter wave plate 2, output to the input end in the first vibration pond 4 through the circularly polarized light of first convex lens 3 transmission light output end from first lens 3, the light output end of first convex lens 3 focuses on focus in the first vibration pond 4, circularly polarized light through 3 transmission of first convex lens focuses on focus place generation SBS effect for the first time and produces the Stokes seed light at the light output end of first convex lens 3, the Stokes seed light that the described first time, SBS produced obtains amplifying afterwards along former road first convex lens 3 in the first vibration pond 4, be input to behind the quarter wave plate 2 on the polaroid 1, Stokes seed light output terminal at quarter wave plate 2 behind quarter wave plate 2 propagation and transformations that the described first time, SBS produced obtains the s polarized light and is polarized sheet 1 reflecting, and be input to the input end of second convex lens 5 through SBS for the first time and from the transmitted light of the output terminal output in the first vibration pond 4, output to the input end in the second vibration pond 6 through the transmitted light of second convex lens 5 transmission light output end from second convex lens 5, the light output end of second convex lens 5 focuses on focus in the second vibration pond 6, transmitted light through 5 transmission of second convex lens focuses on focus place generation SBS effect for the second time and produces the Stokes seed light at the light output end of second convex lens 5, the Stokes seed light that the described second time, SBS produced obtains amplifying afterwards along former road second convex lens 5 in the second vibration pond 6, the first vibration pond 4, first convex lens 3, be input to behind the quarter wave plate 2 on the polaroid 1, Stokes seed light output terminal at quarter wave plate 2 behind quarter wave plate 2 propagation and transformations that described second time, SBS produced obtains the s polarized light and is polarized sheet 1 reflecting, and promptly is required flat top beam through SBS for the second time and from the transmitted light of the output terminal output in the second vibration pond 6.
Embodiment two: in conjunction with Fig. 1 this embodiment is described, in embodiment one, the medium in medium in the described first vibration pond 4 and the described second vibration pond 6 is all selected with absorption coefficient less than 0.005cm
-1Brillouin's medium of (every centimetre).Absorption coefficient is more little, and the energy of SBS light amplitude limit output is just high more, so, for the energy that improves light amplitude limit output of the present invention is selected the little Brillouin's medium of absorption coefficient.
Embodiment three: in conjunction with Fig. 1 this embodiment is described, in embodiment one, the gain coefficient of medium is by the energy decision of required flat top beam in the described first vibration pond 4.Because SBS light amplitude limit output energy is by the system index gain coefficient (in the G=gIL formula, G is the system index gain coefficient, g is the gain coefficient of medium, L is an effective interaction length, I is a light intensity) decide, gain coefficient is more little, and what produce after the SBS effect for the first time is back just high along platform, and the energy of required flat top beam is height just; Gain coefficient is big more, and the generation of SBS effect back is back just low along platform for the first time, and the energy of required flat top beam is just low.
Embodiment four: in conjunction with Fig. 1 this embodiment is described, this embodiment with the difference of embodiment one is: the focal length of described second convex lens 5 is shorter than the focal length of first convex lens 3.By theory as can be known, by changing the focal length of lens, can regulate SBS light amplitude limit output energy and waveform.For the light amplitude limit and the waveform (as shown in Figure 4) of back along " putting down " that obtain higher-energy, first convex lens 3 have been chosen relative long-focus lens; In order to eliminate the forward position peak power (as shown in Figure 3) that produces through after the SBS effect for the first time effectively, second convex lens 5 have been chosen relative short focal length lens.Other steps are identical with embodiment one.After the focal length of lens is determined, because the focus of lens must drop in the vibration pond, so the length in vibration pond is decided by the refractive index of medium and the product of the focal length of lens in the vibration pond; Yet the pool wall of avoiding vibrating is breakdown, so the length in vibration pond must be a bit larger tham above-mentioned product value.The pond that vibrates in addition also must have enough length to finish the process of the depleted realization amplitude limit of pumping light energy, and for example when the pulsewidth of pumping light is long, the length in required vibration pond will be bigger relatively than above-mentioned product value.
Embodiment five: in conjunction with Fig. 1 this embodiment is described, this embodiment with the difference of embodiment one is: the gain coefficient of medium is less than the gain coefficient of medium in the described second vibration pond 6 in the described first vibration pond 4.The medium that gain coefficient is big will cause the Energy extraction time to shorten, and help eliminating the forward position peak power (as shown in Figure 3) that produces through after the SBS effect for the first time.The effect that this embodiment realizes is identical with embodiment four, different is: embodiment four is to eliminate the forward position spike of SBS effect back generation for the first time by the structural parameters of regulating lens, and this embodiment is to eliminate the forward position spike (as shown in Figure 3) of SBS effect back generation for the first time by the parameter of regulating medium in the vibration pond, and the parameter of medium also comprises SBS threshold value, phonon lifetime in the vibration pond.Other steps are identical with embodiment one.
Embodiment six: in conjunction with Fig. 1 this embodiment is described, this embodiment with the difference of embodiment five is: the medium in the described first vibration pond 4 is chosen absorption coefficient less than 0.005cm
-1, the Brillouin medium of gain coefficient in 0.5～10cm/GW (centimetre every gigawatt) scope; Medium in the described second vibration pond 6 is chosen absorption coefficient less than 0.005cm
-1(every centimetre), the gain coefficient Brillouin's medium in 10～70cm/GW scope.Other steps are identical with embodiment five.
Embodiment seven: in conjunction with Fig. 1 this embodiment is described, this embodiment with the difference of embodiment six is: the medium in the described first vibration pond 4 mainly is FC-72 liquid, CCl
4Liquid, FC-75 liquid, C
2Cl
4Liquid, C
4Cl
6A kind of in the liquid; Medium in the described second vibration pond 6 mainly is a carbon disulphide liquid.Other steps are identical with embodiment six.(principal ingredient of FC-72 liquid is C
6F
14, the principal ingredient of FC-75 liquid is C
8F
16O)
Embodiment eight: in conjunction with Fig. 1 this embodiment is described, this embodiment with the difference of embodiment one is: select the SBS threshold value at 0.1～0.5GW/cm in the described second vibration pond 6
2Brillouin's medium in (every square centimeter of gigawatt) scope.The SBS threshold value is more little, and the relaxation time that phonon fields is set up in the second vibration pond 6 is short more, also helps eliminating the forward position peak power (as shown in Figure 3) that SBS effect back produces through the first time.Other steps are identical with embodiment one.
Embodiment nine: in conjunction with Fig. 1 this embodiment is described, this embodiment with the difference of embodiment eight is: the medium in the described second vibration pond 6 is CCl
4Liquid, FC-75 liquid, C
2Cl
4Liquid, C
4Cl
6A kind of in liquid, carbon disulphide liquid, the FC-72 liquid.Other steps are identical with embodiment eight.
Embodiment ten: in conjunction with Fig. 1 this embodiment is described, this embodiment with the difference of embodiment one is: select the Brillouin medium of phonon lifetime in 0.1～1ns (nanosecond) scope in the described second vibration pond 6.Phonon lifetime is short more, and the relaxation time that phonon fields is set up in the second vibration pond 6 is short more, also helps eliminating the forward position peak power (as shown in Figure 3) that SBS effect back produces through the first time.Other steps are identical with embodiment one.
Embodiment 11: in conjunction with Fig. 1 this embodiment is described, this embodiment with the difference of embodiment ten is: the medium in the described second vibration pond 6 is CCl
4Liquid, FC-75 liquid, C
2Cl
4Liquid, C
4Cl
6A kind of in the liquid.Other steps are identical with embodiment ten.
Embodiment 12: this embodiment is described in conjunction with Fig. 1, this embodiment with the difference of embodiment one is: described laser instrument 7 is selected the Nd:YAG Q-switched laser for use, output light wavelength is 1.064 μ m (micron), repetition rate is 1Hz, pulse width is 10ns, highest energy is 50mJ (milli is burnt), and the variation of intake realizes that by adding attenuator the angle of divergence of five times of diffraction limits is 1.6mrad (milliradian); The focal length of described first convex lens 3 is 30cm, and the focal length of described second convex lens 5 is 7.5cm; The pond in the described first vibration pond 4 is long to be 60cm, and the media in the described first vibration pond 4 are FC-72 liquid; The pond in the described second vibration pond 6 is long to be 30cm, and the media in the described second vibration pond 6 are CS
2Liquid.Other steps are identical with embodiment one.In this embodiment, the transmitted light of the pumping light of laser instrument 7, the second vibration pond 6 output terminals output and the energy of the Stokes seed light after the SBS effect are surveyed with energy meter ED200, its pulse waveform is surveyed with PIN photodiode and is come record with digital oscilloscope TDS684A, as Fig. 2, Fig. 3 and shown in Figure 4, what the horizontal ordinate among the figure was represented is the time, and what ordinate was represented is the relative power of light.As seen from Figure 4, obtained flat-topped waveform through behind the light amplitude limit of this embodiment.
Because SBS light amplitude limit output energy is by the system index gain coefficient (in the G=gIL formula, G is the system index gain coefficient, and g is the gain coefficient of medium, and L is an effective interaction length, I is a light intensity) decide, therefore by changing medium parameter and structural parameters may command SBS light amplitude limit output energy.In this embodiment, when the pumping light energy was 30mJ, SBS light amplitude limit output energy was 18mJ for the first time, and the energy of light amplitude limit output for the second time is 10mJ.
Among the present invention, laser instrument 7 can adopt the YAG laser instrument, the YLF Lasers device, ruby laser, KrF laser instruments etc. do not influence effect of the present invention for the selection of laser type, and above-mentioned laser parameters scope is: wavelength coverage is in 248nm～1064nm (nanometer), pulse width range is in 1ps (psec)～100ns, and energy range is in 1 μ J～300J.So long as adopted the secondary stimulated Brillouin scattering system to come the output light of dissimilar laser instruments is realized that the light amplitude limit obtains the method for flat top beam, all in protection scope of the present invention.
Claims (9)
1, utilize the secondary stimulated Brillouin scattering light limiting amplitude to obtain the method for flat top beam, its secondary stimulated Brillouin scattering system is by polaroid (1), quarter wave plate (2), first convex lens (3), the first vibration pond (4), second convex lens (5), the second vibration pond (6) and laser instrument (7) are formed, it is characterized in that realizing that the method that the light amplitude limit obtains flat top beam is: the p polarized light of laser instrument (7) output is input to the input end of polaroid (1) after polaroid (1) transmission and output to the input end of quarter wave plate (2) from the output terminal of polaroid (1), behind quarter wave plate (2) propagation and transformation, obtain circularly polarized light and be input in the input end of first convex lens (3) at the output terminal of quarter wave plate (2), output to the input end in the first vibration pond (4) through the circularly polarized light of first convex lens (3) transmission light output end from first lens (3), the light output end of first convex lens (3) focuses on focus in the first vibration pond (4), circularly polarized light through first convex lens (3) transmission focuses on focus place generation stimulated Brillouin scattering effect for the first time and produces the Stokes seed light at the light output end of first convex lens (3), the Stokes seed light that the described first time, stimulated Brillouin scattering produced obtains amplifying afterwards along former road first convex lens (3) in the first vibration pond (4), be input to behind the quarter wave plate (2) on the polaroid (1), Stokes seed light output terminal at quarter wave plate (2) behind quarter wave plate (2) propagation and transformation that the described first time, stimulated Brillouin scattering produced obtains the s polarized light and is polarized sheet (1) reflecting, and be input to the input end of second convex lens (5) through stimulated Brillouin scattering for the first time and from the transmitted light of the output terminal output in the first vibration pond (4), output to the input end in the second vibration pond (6) through the transmitted light of second convex lens (5) transmission light output end from second convex lens (5), the light output end of second convex lens (5) focuses on focus in the second vibration pond (6), transmitted light through second convex lens (5) transmission focuses on focus place generation stimulated Brillouin scattering effect for the second time and produces the Stokes seed light at the light output end of second convex lens (5), the Stokes seed light that the described second time, stimulated Brillouin scattering produced obtains amplifying afterwards along former road second convex lens (5) in the second vibration pond (6), the first vibration pond (4), first convex lens (3), be input to behind the quarter wave plate (2) on the polaroid (1), Stokes seed light output terminal at quarter wave plate (2) behind quarter wave plate (2) propagation and transformation that described second time, stimulated Brillouin scattering produced obtains the s polarized light and is polarized sheet (1) reflecting, and promptly is required flat top beam through stimulated Brillouin scattering for the second time and from the transmitted light of the output terminal output in the second vibration pond (6).
2, the method for utilizing the secondary stimulated Brillouin scattering light limiting amplitude to obtain flat top beam according to claim 1 is characterized in that the interior medium of medium and the described second vibration pond (6) in the described first vibration pond (4) is all selected with absorption coefficient less than 0.005cm
-1Brillouin's medium.
3, the method for utilizing the secondary stimulated Brillouin scattering light limiting amplitude to obtain flat top beam according to claim 1 is characterized in that the energy decision of the gain coefficient of the interior medium in the described first vibration pond (4) by required flat top beam.
4, the method for utilizing the secondary stimulated Brillouin scattering light limiting amplitude to obtain flat top beam according to claim 1 is characterized in that the focal length of described second convex lens (5) is shorter than the focal length of first convex lens (3).
5, the method for utilizing the secondary stimulated Brillouin scattering light limiting amplitude to obtain flat top beam according to claim 1, the gain coefficient that it is characterized in that the interior medium in the described first vibration pond (4) is less than the interior gain coefficient of medium in the described second vibration pond (6).
6, the method for utilizing the secondary stimulated Brillouin scattering light limiting amplitude to obtain flat top beam according to claim 1 is characterized in that selecting the SBS threshold value at 0.1～0.5GW/cm in the described second vibration pond (6)
2Brillouin's medium in the scope.
7, the method for utilizing the secondary stimulated Brillouin scattering light limiting amplitude to obtain flat top beam according to claim 1 is characterized in that selecting the Brillouin medium of phonon lifetime in 0.1～1ns scope in the described second vibration pond (6).
8, utilize the secondary stimulated Brillouin scattering light limiting amplitude to obtain the method for flat top beam according to claim 1 or 5, it is characterized in that the medium in the described first vibration pond (4) is chosen absorption coefficient less than 0.005cm
-1, the Brillouin medium of gain coefficient in 0.5～10cm/GW scope; Medium in the described second vibration pond (6) is chosen absorption coefficient less than 0.005cm
-1, the Brillouin medium of gain coefficient in 10～70cm/GW scope.
9, according to claim 1,2, the 4 or 5 described methods of utilizing the secondary stimulated Brillouin scattering light limiting amplitude to obtain flat top beam, it is characterized in that described laser instrument (7) selects the Nd:YAG Q-switched laser for use, output light wavelength is 1.064 μ m, repetition rate is 1Hz, pulse width is 10ns, highest energy is 50mJ, and the variation of intake realizes that by adding attenuator the angle of divergence of five times of diffraction limits is 1.6mrad; The focal length of described first convex lens (3) is 30cm, and the focal length of described second convex lens (5) is 7.5cm; The pond in the described first vibration pond (4) is long to be 60cm, and the medium in the described first vibration pond (4) is a FC-72 liquid; The pond in the described second vibration pond (6) is long to be 30cm, and the medium in the described second vibration pond (6) is CS
2Liquid.
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| CN100385331C (en) * | 2006-05-31 | 2008-04-30 | 哈尔滨工业大学 | Laser pulse shaping device and method based on two-cell stimulated Brillouin scattering system |
| CN104062012B (en) * | 2014-07-18 | 2015-12-09 | 哈尔滨理工大学 | Method and the device that Brillouin signal frequency domain stares pump probe is realized based on detection light flat-top spectrum modulation method |
| CN104678559B (en) * | 2015-03-23 | 2017-02-01 | 吕志伟 | Non-collineation serial beam grouping method and device based on excited brillouin scattering |
| CN107193128B (en) * | 2017-07-05 | 2019-06-21 | 厦门大学 | A kind of light beam regulation method for realizing flat-top focus |
| CN112038874B (en) * | 2020-08-03 | 2024-05-28 | 河北工业大学 | Self-pumping SBS pulse compression system of double pools |
| CN117647900B (en) * | 2024-01-30 | 2024-04-02 | 中国科学院长春光学精密机械与物理研究所 | Phase modulation optical limiter and design method thereof |
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| JPH11271827A (en) * | 1998-03-23 | 1999-10-08 | Matsushita Electric Ind Co Ltd | High-frequency modulated signal generating device |
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| CN1740889A (en) | 2006-03-01 |
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