CN103296577A - kHz green ray picosecond laser device used for satellite distance measurement - Google Patents
kHz green ray picosecond laser device used for satellite distance measurement Download PDFInfo
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- CN103296577A CN103296577A CN2013101923048A CN201310192304A CN103296577A CN 103296577 A CN103296577 A CN 103296577A CN 2013101923048 A CN2013101923048 A CN 2013101923048A CN 201310192304 A CN201310192304 A CN 201310192304A CN 103296577 A CN103296577 A CN 103296577A
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Abstract
The invention relates to a kHz green ray picosecond laser device used for satellite distance measurement, and belongs to the field of laser device technology. An all-solid-state Nd: YVO4-SESAM mode-locked laser unit outputs a string of small-energy picosecond laser pulse as seed light of the kHz green ray picosecond laser device used for satellite distance measurement, the seed light is amplified to 2-3mJ through an all-solid-state kHzNd:YAG regenerative amplifier unit, and then picosecond laser pulse with 1-2 W of average power, 1-2 kHz of repetition frequency and 532 nm of wave length is outputted through a frequency doubling unit. The kHz green ray picosecond laser device used for the satellite distance measurement is narrow in pulse width (<20ps), high in repetition (kHz), large in power (2W) and high in signal to noise ration (>10<2>), and high-precision high-echo-rate high-altitude satellite daytime measurement can be realized.
Description
Technical field
The present invention is based on all solid state picosecond laser of satellite ranging, comprises the Nd:YVO of semiconductor laser diode (LD) pumping
4The Nd:YAG regenerative amplifier of SESAM locked mode picosecond laser, LD pumping and the 1064nm wavelength is converted to the frequency multiplier of 532nm, laser works frequency 1-2 KHz (kHz), laser pulse width is less than 20 psecs (ps).
Background technology
Satellite laser ranging (SLR) (Satellite Laser Ranging, SLR) one that to be the phase at the beginning of the sixties in last century initiated by NASA (NASA) is intended to utilize space technology to study the technological means of geodynamics, geodesy, geophysics and astronomy etc., also is important observation method of astrogeodynamics.Satellite ranging with laser experienced from nanosecond (ns) pulsewidth Q-switched laser to the mode-locked laser of psec pulsewidth (ps), range accuracy is brought up to Centimeter Level from meter level; Repetition rate from 10 hertz (Hz) to the hundreds of hertz; From the lamp pumping to semiconductor laser pumping.The kHz picosecond laser is that precision is the highest, a kind of satellite ranging LASER Light Source of echo data amount maximum as satellite ranging system LASER Light Source at present, and its satellite ranging precision can reach a millimeter magnitude, and the earth satellite orbit determination accuracy can reach a centimetre magnitude.。
Summary of the invention
The invention provides a kind of satellite ranging kHz picosecond laser, it comprises:
Satellite ranging kHz green glow picosecond laser comprises:
All solid state Nd:YVO
4-SESAM mode-locked laser unit, for generation of repetition in 50～80MHz, laser pulse width 10～20ps, the single pulse energy psec seed light more than or equal to 1nJ;
All solid state kHz Nd:YAG regenerative amplifier unit is used for realization to the amplification of psec seed light energy, operating frequency 1-2kHz;
The frequency multiplication unit, being used for the 1064nm wavelength conversion is the 532nm wavelength.
All solid state Nd:YVO
4The pulse of a string little energy picosecond laser is exported as satellite ranging kHz picosecond laser seed light in-SESAM mode-locked laser unit, by all solid state kHz Nd:YAG regenerative amplifier unit it is amplified to 2-3mJ, realizes the picosecond laser pulse output of average power 1-2W, repetition rate 1-2kHz, wavelength 532nm again by the frequency multiplication unit.
Described all solid state Nd:YVO
4-SESAM mode-locked laser unit comprises laser diode 1, GRIN Lens 2, laser crystal A3, the chamber mirror unit that sets gradually along light path, and laser diode 1 and laser crystal A3 control temperature by semiconductor cooler, and temperature-controlled precision is less than ± 0.2 ° of C.
Described all solid state Nd:YVO
4-SESAM mode-locked laser lumen mirror unit comprises concave mirror A14, plane mirror A15, flat output mirror 6, plane mirror A27, concave mirror A28 and the SESAM locked mode element 9 that sets gradually along the oscillation light direction; Flat output mirror 6 output seed light, angle is less than 8 ° between concave mirror A14 and the concave mirror A28 incident light reverberation, angle is less than 20 ° between plane mirror A15 and the plane mirror A27 incident light reverberation, concave mirror A14 equals the radius of curvature of concave mirror A14 apart from the distance of laser crystal A3, and concave mirror A28 equals the radius of curvature of concave mirror A28 apart from the distance of SESAM locked mode element 9.
Described all solid state Nd:YVO
4-SESAM mode-locked laser unit output polarization state is horizontal polarization light.
Described all solid state kHz Nd:YAG regenerative amplifier unit along light path set gradually by polarizer B112, half-wave plate 13, Faraday polarization apparatus 14, polarizer B215, quarter-wave plate B116, Pockers cell 17, convex reflecting mirror B118, light sets gradually Pockers cell 17 through the upper edge, reflective loop of convex reflecting mirror B118, quarter-wave plate B116, polarizer B215, polarizer B319, gain unit 20, quarter-wave plate B221, diaphragm 22 and convex reflecting mirror B223, polarizer B112, B215, B319 equals 56 ° ± 1 ° placement by incidence angle, the half-wave plate optical axis becomes 22.5 ° of angles to place with horizontal polarization incident light electric vector vibration plane angle, place at quarter-wave plate B116 optical axis and horizontal polarization incident light electric vector vibration plane angle at 45, quarter-wave plate B221 optical axis becomes 0 ° of angle to place all solid state Nd:YVO with vertical polarization incident light electric vector vibration plane
4The horizontal polarization seed light of-SESAM mode-locked laser unit output enters all solid state kHzNd:YAG regenerative amplifier unit through 45 ° of speculum A10 and 45 ° of total reflective mirror B11 reflections, and polarizer B112 goes out the regenerative amplification photoconduction.
Described gain unit 20 is made of pulse 1-2kHz semiconductor laser bar bar 20a and laser crystal B20b, laser crystal B20b is positioned at semiconductor laser bar bar 20a center, semiconductor laser bar bar 20a presses hexagonal angle or 60 ° of angles distributions are placed, gain unit is by recirculated water cooling and temperature control, and temperature-controlled precision is less than ± 0.5 ° of C.
Described regenerative amplifier resonant cavity is the biconvex speculum chamber that is made of convex reflecting mirror B118 and convex reflecting mirror B223.
Described frequency multiplication unit is made of the 45 speculum B24 that set gradually along light path, LBO frequency-doubling crystal, 45 ° of saturating-anti-mirror C126 and 45 ° of saturating-anti-mirror C227.
Described frequency-doubling crystal is I class 1064-532nm phase matched lbo crystal or temperature phase matched lbo crystal.
Two 45 ° saturating-anti-mirror C126 and the C227 in described frequency multiplication unit are coated with 532nm high-reflecting film and 1064nm high transmittance film, and last 532nm light is by 45 ° of saturating-anti-mirror C227 reflection outputs.
Compared with prior art, the present invention has the following advantages:
1, output pulse width of the present invention narrow (＜20ps), the range accuracy height, ground target range accuracy can reach 5mm.
2, output laser pulse repetition rate height of the present invention (kHz) can improve the echo rate of satellite ranging.
3, the present invention exports average laser power height (2W), can realize high rail (36000km) satellite and daytime satellite ranging.
4, output laser pulse signal to noise ratio height of the present invention (〉 10
2), can improve the accuracy rate that the satellite ranging system surveys.
Description of drawings
Fig. 1 is index path structural representation of the present invention;
Fig. 2 is regenerative amplifier gain unit structural representation figure;
Concrete symbol description is as follows:
1-laser diode 2-GRIN Lens
3-laser crystal 4-concave mirror A1
5-plane mirror A1 6-flat output mirror
7-plane mirror A2 8-concave mirror A2
9-SESAM 10-45 ° of speculum A
11-45 ° of speculum B 12-polarizer B1
13-half-wave plate 14-Faraday polarization apparatus
15-polarizer B2 16-λ/4 wave plate B1
17-BBO Pockers cell 18-convex reflecting mirror B1
19-polarizer B3 20-gain unit
20a-semiconductor laser diode bar bar 20b-laser crystal B
21-λ/4 wave plate B2 22-lens
24-45 ° of speculum C of 23-convex reflecting mirror B2
26-45 ° of saturating anti-mirror C1 of 25-frequency-doubling crystal
27-45 ° of saturating anti-mirror C2
Embodiment
The present invention will be further described below in conjunction with accompanying drawing.
As shown in Figure 1, in one embodiment of the invention, the invention provides a kind of satellite ranging kHz picosecond laser, it comprises: the mode-locked laser unit, be used for output psec seed laser, and wherein exporting light is horizontal polarization light; The regenerative amplifier unit is used for the seed laser pulse energy is amplified; The frequency multiplication unit is used for fundamental frequency light is carried out frequency multiplication, and wherein lambda1-wavelength is 1064nm, and the emergent light wavelength is 532nm.
As shown in Figure 1, mode-locked laser unit among the present invention comprises laser diode-pumped light source 1, GRIN Lens 2, laser crystal 3, concave mirror 4, plane mirror 5, flat output mirror 6, plane mirror 7, concave mirror 8 and locked mode element SESAM9, said elements sets gradually along the oscillation light direction, and emergent light is reflected in the regenerative amplifier unit by 45 ° of speculums 10 and 11 through outgoing mirror 6 backs.
As shown in Figure 1, the regenerative amplifier unit among the present invention comprises that polarizer 12, half-wave plate 13 and faraday's optical rotator 14 have constituted the importing of regenerative amplifier seed light and the amplification photoconduction goes out device; Convex reflecting mirror 18 and 23 constitutes two chamber mirrors of regenerative amplifier resonant cavity; The seed light of horizontal polarization still is horizontal polarization behind polarizer 12, half-wave plate 13 and faraday's optical rotator 14, imports the regenerative amplification resonant cavity through polarizer 15; Light is 0 through voltage on λ/4 wave plates 16 and Pockers cell 17(Pockers cell this moment), arrive convex reflecting mirror 18 backs by total reflection, be 0 by voltage on λ/4 wave plates 15 and the Pockers cell 17(Pockers cell 17 this moment again), its polarization direction becomes orthogonal polarized light, be polarized sheet 15 and polarizer 19 reflections, and be exaggerated by the gain unit of being formed by laser crystal B20b, semiconductor laser diode array 20a 20, thermal birefringence effect and thermal lensing effect are respectively by λ/4 wave plates 21 and lens 22 compensation simultaneously.Give on the Pockers cell 17 and add λ/4 wavelength voltages and regulate first delay time, select single seed optical pulse, regulate the selected seed light of second delay time control then and in resonant cavity, come and go number of times, both be exaggerated once by gain unit 20 seed light at every turn, its round number of times is determined by gain and the loss of resonator, when reaching gain saturation, light is after gain unit 20 outgoing, remove and add λ/4 wavelength voltages on the Pockers cell, through polarizer 19 and 15 reflections, directive λ/4 wave plates 16, behind the Pockers cell 17, passed through λ/4 wave plates 16 again by convex reflecting mirror 18 reflections, orthogonal polarized light becomes horizontal polarization through polarizer 15 transmissions, and the seed light that be imported into this moment has been finished the amplification process in the chamber.Horizontal polarization light after the amplification is through faraday's optical rotator 14, half-wave plate 13, and its polarization state is rotated, and becomes orthogonal polarized light, is polarized sheet 12 reflections, has finally finished the derivation of amplifying light.
As shown in Figure 1, the frequency multiplication unit among the present invention comprises frequency-doubling crystal, and the 1064nm fundamental frequency light of incident is converted to 532nm light through the nonlinear effect of frequency-doubling crystal, finishes the output of 532nm light by 45 ° of speculums 26 and 27 of the saturating 1064nm of anti-532nm.
Certainly, adopt above-mentioned optimal technical scheme just for the ease of understanding to illustrating that the present invention carries out, the present invention also can have other embodiment, protection scope of the present invention is not limited to this.Under the situation that does not deviate from spirit of the present invention and essence thereof, the person of ordinary skill in the field works as can make various corresponding changes and distortion according to the present invention, but these corresponding changes and distortion all should belong to the protection range of claim of the present invention.
Claims (10)
1. satellite ranging is characterized in that with kHz green glow picosecond laser, comprising:
All solid state Nd:YVO
4-SESAM mode-locked laser unit, for generation of repetition in 50～80MHz, laser pulse width 10～20ps, the single pulse energy psec seed light more than or equal to 1nJ;
All solid state kHz Nd:YAG regenerative amplifier unit is used for realization to the amplification of psec seed light energy, operating frequency 1-2kHz;
The frequency multiplication unit, being used for the 1064nm wavelength conversion is the 532nm wavelength.
All solid state Nd:YVO
4The pulse of a string little energy picosecond laser is exported as satellite ranging kHz picosecond laser seed light in-SESAM mode-locked laser unit, by all solid state kHz Nd:YAG regenerative amplifier unit it is amplified to 2-3mJ, realizes the picosecond laser pulse output of average power 1-2W, repetition rate 1-2kHz, wavelength 532nm again by the frequency multiplication unit.
2. satellite ranging according to claim 1 is characterized in that described all solid state Nd:YVO with kHz green glow picosecond laser
4-SESAM mode-locked laser unit comprises laser diode (1), GRIN Lens (2), the laser crystal A(3 that sets gradually along light path), the chamber mirror unit, laser diode (1) and laser crystal A(3) by semiconductor cooler control temperature, temperature-controlled precision is less than ± 0.2 ° of C.
3. satellite ranging according to claim 2 is characterized in that described all solid state Nd:YVO with kHz green glow picosecond laser
4-SESAM mode-locked laser lumen mirror unit comprises the concave mirror A1(4 that sets gradually along the oscillation light direction), plane mirror A1(5), flat output mirror (6), plane mirror A2(7), concave mirror A2(8) and SESAM locked mode element (9); Angle is less than 8 ° between concave mirror A1 (4) and concave mirror A2 (8) the incident light reverberation; Plane mirror A1(5) and plane mirror A2(7) between the incident light reverberation angle less than 20 °; Concave mirror A1 (4) is apart from laser crystal A(3) distance equal the radius of curvature of concave mirror A1 (4); Concave mirror A2 (8) equals the radius of curvature of concave mirror A2 (8) apart from the distance of SESAM locked mode element (9); Flat output mirror (6) output seed light.
4. satellite ranging according to claim 2 is characterized in that described all solid state Nd:YVO with kHz green glow picosecond laser
4-SESAM mode-locked laser unit output polarization state is horizontal polarization light.
5. satellite ranging according to claim 1 is with kHz green glow picosecond laser, it is characterized in that, described all solid state kHz Nd:YAG regenerative amplifier unit along light path set gradually by polarizer B1(12), half-wave plate (13), Faraday polarization apparatus (14), polarizer B2(15), quarter-wave plate B1(16), Pockers cell (17), convex reflecting mirror B1(18), light is through convex reflecting mirror B1(18) upper edge, reflective loop set gradually Pockers cell (17), quarter-wave plate B1(16), polarizer B2(15), polarizer B3(19), gain unit (20), quarter-wave plate B2(21), diaphragm (22) and convex reflecting mirror B2(23), polarizer B1(12), B2(15), B3(19) equal 56 ° ± 1 ° placement by incidence angle, half-wave plate (13) optical axis becomes 22.5 ° of angles to place with horizontal polarization incident light electric vector vibration plane angle, quarter-wave plate B1(16) place at optical axis and horizontal polarization incident light electric vector vibration plane angle at 45, quarter-wave plate B2(21) optical axis becomes 0 ° of angle to place all solid state Nd:YVO with vertical polarization incident light electric vector vibration plane
4The horizontal polarization seed light of-SESAM mode-locked laser unit output is through 45 ° of speculum A(10) and 45 ° of total reflective mirror B(11) reflect enter all solid state kHz Nd:YAG regenerative amplifier unit, polarizer B1(12) the regenerative amplification photoconduction is gone out.
6. satellite ranging according to claim 5 is with kHz green glow picosecond laser, it is characterized in that, described gain unit (20) is by pulse (1-2kHz operating frequency) semiconductor laser bar bar (20a) and laser crystal B(20b) constitute, laser crystal B(20b) is positioned at semiconductor laser bar bar (20a) center, semiconductor laser bar bar (20a) presses hexagonal angle or 60 ° of angles distributions are placed, gain unit is by recirculated water cooling and temperature control, and temperature-controlled precision is less than ± 0.5 ° of C.
7. satellite ranging according to claim 5 is characterized in that with kHz green glow picosecond laser described regenerative amplifier resonant cavity is by convex reflecting mirror B1(18) and convex reflecting mirror B2(23) the biconvex speculum chamber of formation.
8. satellite ranging according to claim 1 is with kHz green glow picosecond laser, it is characterized in that described frequency multiplication unit is by the 45 speculum B(24 that set gradually along light path), LBO frequency-doubling crystal, 45 ° be saturating-anti-mirror C1(26) and 45 ° of saturating-anti-mirror C2(27) formation.
9. satellite ranging according to claim 8 is characterized in that with kHz green glow picosecond laser described frequency-doubling crystal is I class 1064-532nm phase matched lbo crystal or temperature phase matched lbo crystal.
10. satellite ranging according to claim 8 is with kHz green glow picosecond laser, it is characterized in that, two 45 ° of described frequency multiplication unit are saturating-anti-mirror C1(26) and C2(27), be coated with 532nm high-reflecting film and 1064nm high transmittance film, and last 532nm light is by 45 ° of saturating-anti-mirror C2(27) reflection output.
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| CN2013101923048A CN103296577A (en) | 2013-05-22 | 2013-05-22 | kHz green ray picosecond laser device used for satellite distance measurement |
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| CN2013101923048A CN103296577A (en) | 2013-05-22 | 2013-05-22 | kHz green ray picosecond laser device used for satellite distance measurement |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104767108A (en) * | 2015-04-27 | 2015-07-08 | 北京工业大学 | Regenerative amplifier provided with multiplied resonator cavity |
| CN104765176A (en) * | 2015-04-27 | 2015-07-08 | 北京工业大学 | Liquid crystal spatial modulation regenerative amplifier |
| CN108551076A (en) * | 2018-06-22 | 2018-09-18 | 深圳烯光科技有限公司 | A kind of adjustable dual wavelength of repetition rate receives a joule picosecond laser |
| CN108767629A (en) * | 2018-03-26 | 2018-11-06 | 中国科学院上海光学精密机械研究所 | The active multi-way chirped pulse stretcher of big energy |
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| CN101055401A (en) * | 2007-05-25 | 2007-10-17 | 北京工业大学 | Whole-solid kHz picosecond laser pulse regeneration amplifier |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104767108A (en) * | 2015-04-27 | 2015-07-08 | 北京工业大学 | Regenerative amplifier provided with multiplied resonator cavity |
| CN104765176A (en) * | 2015-04-27 | 2015-07-08 | 北京工业大学 | Liquid crystal spatial modulation regenerative amplifier |
| CN104765176B (en) * | 2015-04-27 | 2017-06-30 | 北京工业大学 | A kind of liquid crystal spatial modulates regenerative amplifier |
| CN104767108B (en) * | 2015-04-27 | 2017-10-27 | 北京工业大学 | A kind of double regenerative amplifier of resonator |
| CN108767629A (en) * | 2018-03-26 | 2018-11-06 | 中国科学院上海光学精密机械研究所 | The active multi-way chirped pulse stretcher of big energy |
| CN108551076A (en) * | 2018-06-22 | 2018-09-18 | 深圳烯光科技有限公司 | A kind of adjustable dual wavelength of repetition rate receives a joule picosecond laser |
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Application publication date: 20130911 |