CN102508225B - Double-shaft laser remote sensing instrument ground detection and calibration system and detection and calibration method - Google Patents

Abstract

The invention provides a double-shaft laser remote sensing instrument ground detection and calibration system, which comprises a simulation echo generator, a two-dimensional moving platform, a heavy-caliber long-focus collimator and a light beam quality analyzer. One side of the heavy-caliber long-focus collimator is provided with a beam splitter and a pyramid prism, and the other side of the heavy-caliber long-focus collimator is provided with a total-reflection mirror. The simulation echo generator is composed of a photolectric transducer, a time delay unit, an optical fiber output laser, optical fiber and an electronic control optical attenuator. The optical fiber output laser is connected with one end of the optical fiber, and the other end of the optical fiber is located on the other side of the heavy-caliber long-focus collimator. A port of the other end of the optical fiber is located on a focal plane of the heavy-caliber long-focus collimator and fixed on the two-dimensional moving platform. The detection and calibration system is capable of obtaining far-field light beam quality distribution and detectivity of the detected active and passive laser remote sensing instrument and is capable of obtaining geometric construction factors of the detected active and passive laser remote sensing instrument.

Description

Twin shaft laser remote sensing instrument ground detection scaling system and detection calibrating method

Technical field

The invention belongs to laser active remote sensing field of detecting, relate to twin shaft laser remote sensing instrument ground detection scaling system, also relate to the systematic parameter-detectivity of this system to the moving laser remote sensing instrument of main quilt, the method that far field beam quality distributes, the system geometries factor detects and demarcates.

Background technology

Since laser is born, the fast development of laser science technology.Laser remote sensing instrument has been widely used in the research fields such as celestial body measurement, aerial target detection, Laser Atmospheric Transmission, global climate prediction, aerosol radiative effect and atmospheric environment as a kind of active remote sensing Detection Techniques.The principle of work of laser remote sensing system is that the laser beam pulses of being sent by laser instrument enters atmosphere, by telescope, received the scatter echo signal producing after laser beam and atmosphere or irradiated object effect, and after optics light-splitting processing and photodetector system conversion, input message treatment facility (mostly being computing machine) carries out data inversion processing, to obtaining the information such as distance, spectrum, image.

Along with the expansion of laser remote sensing instrument application scope and the raising of application demand, the detectivity of people to system and system stability require also more and more higher, and also the ground calibration to remote sensing system and test performance are had higher requirement for these.The detectivity index of laser remote sensing instrument mainly comprises system detection accuracy, accuracy, investigative range (maximum ranging, minimum ranging), resolution of ranging and detection probability (false alarm rate, false dismissed rate).Except detectivity, laser detection system also has a lot of performance parameters to demarcate and to test, and these parameters comprise laser energy, laser pulse width, repetition frequency, laser beam divergence, laser far field distribution, system delay constant, the minimum detection sensitivity of system, field of view of receiver angle, optical axis registration.At these, need in the parameter of Accurate Calibration and test, except the parameter relevant to laser characteristics has unified method of testing, other systematic parameter there is no the commercial device of standard or relevant apparatus at present to its Accurate Calibration, and this has brought puzzlement to demarcation of instrument detection performance.And same instrument be after experience different conditions changes, its performance parameter can change, the particularly geometry factor of system, and the variation of the geometry factor will directly have influence on the detectivity of system.This just requires to have the instrument of standard or equipment to test it, and calibrates situation of change in time.

Summary of the invention

The object of this invention is to provide a kind of twin shaft laser remote sensing instrument ground detection and calibration system, so that can carry out detection and the demarcation of systematization, quantification to the system performance of laser remote sensing instrument and instrument parameter.

Another object of the present invention is to provide the detectivity of said system to the moving laser remote sensing instrument of main quilt, the method that far field beam quality distributes and the system geometries factor is carried out high-precision detection and demarcation.

The technical solution adopted in the present invention is that twin shaft laser remote sensing instrument ground detection and scaling system, comprise analogue echo generator, two-dimensional movement platform, large-aperture long-focus parallel light tube and beam quality analysis instrument; One side of large-aperture long-focus parallel light tube is provided with beam splitter and prism of corner cube, and the opposite side of large-aperture long-focus parallel light tube is provided with total reflective mirror; Analogue echo generator is comprised of photoelectric commutator, chronotron, optical fiber output laser, optical fiber and automatically controlled fibre optic attenuator; Photoelectric commutator and chronotron are between beam splitter and optical fiber output laser, and beam splitter is for the pulse laser being sent by measured laser remote sensing instrument is divided into two parts, and wherein a part of pulse laser reflects to photoelectric commutator; Photoelectric commutator is for being converted to electric signal by the pulse laser being reflected by beam splitter; Chronotron is for the time delay of electric signal; Optical fiber output laser for exporting pulse laser after being triggered by the electric signal after time delay, optical fiber output laser is connected with one end of optical fiber, the other end of optical fiber is positioned at the opposite side of large-aperture long-focus parallel light tube, the port of the optical fiber other end is positioned on the focal plane of large-aperture long-focus parallel light tube, and is fixed on two-dimensional movement platform; Automatically controlled fibre optic attenuator is arranged on optical fiber; The photosurface of beam quality analysis instrument is placed on the focal plane that large-aperture long-focus parallel light tube reflected by total reflective mirror.

Another technical scheme of the present invention is, utilizes above-mentioned twin shaft laser remote sensing instrument ground detection and scaling system to obtain the method for measured laser remote sensing instrument detectivity, comprises following operation steps:

Step 1: measured laser remote sensing instrument sends pulse laser, pulse laser is divided into two parts through beam splitter;

Step 2: wherein a part of pulse laser enters total reflective mirror after the refraction of large-aperture long-focus parallel light tube, by total reflective mirror reflection laggard enter on beam quality analyser photosurface, form Emission Lasers hot spot, beam quality analysis instrument gathers the far field beam quality that this Emission Lasers hot spot obtains measured laser remote sensing instrument and distributes;

Step 3: another part pulse laser is converted to electric signal through reflecting into into photoelectric commutator of beam splitter, after the time delay of chronotron, trigger optical fiber output laser again, optical fiber output laser is exported the pulse laser after automatically controlled fibre optic attenuator decay by optical fiber by the other end of optical fiber, pulse laser becomes directional light through large-aperture long-focus parallel light tube, wherein a part of directional light is after 180 ° of reflections of prism of corner cube again on the photosurface by directive beam quality analysis instrument after the transmission of large-aperture long-focus parallel light tube and the reflection of total reflective mirror, form analogue echo hot spot, and another part directional light enters measured laser remote sensing instrument and provides output signal as remote analogue echo,

Step 4: the position of comparing Emission Lasers hot spot and analogue echo hot spot by beam quality analysis instrument, adjust the relative position of measured laser remote sensing instrument and laser remote sensing instrument ground detection and scaling system, Emission Lasers hot spot and analogue echo hot spot are overlapped on beam quality analysis instrument, realize measured laser remote sensing instrument and dock with the light path of scaling system with laser remote sensing instrument ground detection;

Step 5: until the light path of measured laser remote sensing instrument and laser remote sensing instrument ground detection and scaling system to after connecting, adjust the attenuation multiple of automatically controlled fibre optic attenuator, make the output signal of measured laser remote sensing instrument reach detection limit, utilize energy meter detection fiber output laser output energy value, and according to automatically controlled fibre optic attenuator attenuation multiple value, obtain the minimum detectable energy values P of laser remote sensing instrument _rmin, according to formula (1), obtain the detectivity of measured laser remote sensing instrument:

$R_{\max }={\left(\frac{{\mathrm{KP}}_t{\mathrm{\τ}}_0{\mathrm{\τ}}^2{A}_r\mathrm{\σ}}{{\mathrm{\π}}^2{\mathrm{\θ}}_t^2{P}_{r\min }}\right)}^{\frac{1}{4}}---\left(1\right)$

In formula, R _maxbe that the observable maximum distance of laser remote sensing instrument is detectivity, K is that the beam quality being recorded by beam quality analysis instrument distributes, P _toptical fiber output laser output power, τ ₀be optical system efficiency, τ is measured laser remote sensing instrument to laser atmospheric transmittance in target range, the radar cross section that σ is detected target, A _rreceiving optics aperture area, θ _tutilizing emitted light beam divergence angle, P _rminbeing the minimum detectable power of laser distance measuring system, is also system detection sensitivity.

The technical scheme that the present invention also adopts is, utilizes above-mentioned twin shaft laser remote sensing instrument ground detection and scaling system to obtain the method for the measured laser remote sensing instrument geometry factor, comprises following operation steps:

Step 1: measured laser remote sensing instrument sends pulse laser, pulse laser is divided into two parts through beam splitter;

Step 2: wherein a part of pulse laser enters total reflective mirror after the refraction of large-aperture long-focus parallel light tube, by total reflective mirror reflection laggard enter on beam quality analyser photosurface, form Emission Lasers hot spot, beam quality analysis instrument gathers the far field beam quality that this Emission Lasers hot spot obtains measured laser remote sensing instrument and distributes;

Step 3: another part pulse laser is converted to electric signal through reflecting into into photoelectric commutator of beam splitter, after the time delay of chronotron, trigger optical fiber output laser again, optical fiber output laser is exported the pulse laser after automatically controlled fibre optic attenuator decay by optical fiber by the other end of optical fiber, pulse laser becomes directional light through large-aperture long-focus parallel light tube, wherein a part of directional light is after 180 ° of reflections of prism of corner cube again on the photosurface by directive beam quality analysis instrument after the transmission of large-aperture long-focus parallel light tube and the reflection of total reflective mirror, form analogue echo hot spot, and another part directional light enters measured laser remote sensing instrument and provides output signal as remote analogue echo,

Step 4: the position of comparing Emission Lasers hot spot and analogue echo hot spot by beam quality analysis instrument, adjust the relative position of measured laser remote sensing instrument and laser remote sensing instrument ground detection and scaling system, Emission Lasers hot spot and analogue echo hot spot are overlapped on beam quality analysis instrument, realize laser remote sensing instrument and dock with the light path of scaling system with laser remote sensing instrument ground detection;

Step 5: the position of optical fiber other end end face while utilizing two-dimensional movement platform to record measured laser remote sensing instrument and laser remote sensing instrument ground detection and scaling system to achieve a butt joint, is recorded as (L ₀, 0); By two-dimensional movement platform control optical fiber other end end face, on long-focus heavy caliber parallel light tube focal plane, move horizontally, monitor measured laser remote sensing instrument output signal situation simultaneously, the position of two-dimensional movement platform when recording laser remote sensing instrument output signal becomes critical point, the shift position of two-dimensional movement platform is with respect to (L ₀, 0) and its two-dimensional movement position is designated as (L _l, 0) and (L _r, 0); By two-dimensional movement platform control optical fiber other end end face, on long-focus heavy caliber parallel light tube focal plane, vertically move, monitor measured laser remote sensing instrument output signal situation simultaneously, the position of two-dimensional movement platform when recording laser remote sensing instrument output signal becomes critical point, the shift position of two-dimensional movement platform is with respect to (L ₀, 0) and its two-dimensional movement position is designated as (L _u, 0) and (L _d, 0); According to formula (2), obtain the laser remote sensing instrument geometry factor, also claim geometric overlap factor:

${\mathrm{\δ}}_1=\frac{L_L+L_R}{2f}-\frac{L_0}{f}$ ${\mathrm{\δ}}_2=\frac{L_U+L_D}{2f}-\frac{L_0}{f}---\left(2\right)$

In formula, f is the focal length of large-aperture long-focus parallel light tube, δ ₁for the tested laser remote sensing instrument geometry factor in the horizontal direction, δ ₂for the geometry factor of tested laser remote sensing instrument in the vertical direction.

The invention has the beneficial effects as follows, the far field beam quality that can obtain exactly the moving laser remote sensing instrument of tested main quilt distributes and detectivity, and can obtain exactly the geometry factor of the moving laser remote sensing instrument of tested main quilt, to solve spaceborne instrument before and after the experiment of experience various temperature, hot vacuum environment, the geometry factor changes and a difficult problem that cannot Accurate Calibration.

Accompanying drawing explanation

Fig. 1 is the structure principle chart of laser remote sensing instrument ground detection of the present invention and calibration system.

In figure, 1. beam splitter, 2. photoelectric commutator, 3. chronotron, 4. optical fiber output laser, 5. optical fiber, 6. automatically controlled fibre optic attenuator, 7. two-dimensional movement platform, 8. total reflective mirror, 9. large-aperture long-focus parallel light tube, 10. beam quality analysis instrument, 11. prism of corner cubes, 12. collimating and beam expanding systems, 13. pulsed lasers, 14. receiving telescopes, 15. signal processing circuits.

Embodiment

As shown in Figure 1, the invention provides a kind of twin shaft laser remote sensing instrument ground detection and scaling system, comprise analogue echo generator, two-dimensional movement platform 7, large-aperture long-focus parallel light tube 9 and beam quality analysis instrument 10; One side of large-aperture long-focus parallel light tube 9 is provided with beam splitter 1 and prism of corner cube 11, and the opposite side of large-aperture long-focus parallel light tube 9 is provided with total reflective mirror 8; Analogue echo generator is comprised of photoelectric commutator 2, chronotron 3, optical fiber output laser 4, optical fiber 5 and automatically controlled fibre optic attenuator 6; Photoelectric commutator 2 and chronotron 3 are between beam splitter 1 and optical fiber output laser 4, and beam splitter 1 is for the pulse laser being sent by measured laser remote sensing instrument is divided into two parts, and wherein a part of pulse laser reflects to photoelectric commutator 2; Photoelectric commutator 2 is for being converted to electric signal by the pulse laser being reflected by beam splitter 1; Chronotron 3 is for the time delay of electric signal; Optical fiber output laser 4 for exporting pulse laser after being triggered by the electric signal after time delay, optical fiber output laser 4 is connected with one end of optical fiber 5, the other end of optical fiber 5 is positioned at the opposite side of large-aperture long-focus parallel light tube 9, the port of optical fiber 5 other ends is positioned on the focal plane of large-aperture long-focus parallel light tube 9, and is fixed on two-dimensional movement platform 7; Automatically controlled fibre optic attenuator 6 is arranged on optical fiber 5; The photosurface of beam quality analysis instrument 10 is placed on the focal plane that large-aperture long-focus parallel light tube 9 reflected by total reflective mirror 8.

In said system, the output wavelength of optical fiber output laser 4 is 1064nm, and pulsed frequency is adjustable at 1hz～1000hz; Optical fiber 5 is single-mode fiber, and core diameter is 9um; It is the desk-top attenuator of SUN-FVA-T that automatically controlled fibre optic attenuator 6 adopts model; Large-aperture long-focus parallel light tube 9 adopts transmission-type system, focal length is 4 meters, bore is 500mm, adopt large-aperture long-focus parallel light tube 9 to produce bigbore parallel beam, the sensing of this parallel beam and energy can accurately be controlled and demarcate, this heavy caliber light beam is in order to simulate by the echo beam of the reflections such as atmosphere, object or scattering generation, utilize this echo beam to carry out analog detection to laser remote sensing instrument, result of detection is carried out to analysis and calculation and just can obtain the omnibearing performance parameter index of laser remote sensing instrument; Prism of corner cube 11 act as analogue echo light beam 180 degree is reflected back to large-aperture long-focus parallel light tube 9; Beam quality analysis instrument 10 adopts the Beammaster knife edge type laser beam analyzer of relevant company.

Wherein, measured laser remote sensing instrument comprises pulsed laser 13, collimating and beam expanding system 12, receiving telescope 14 and signal processing circuit 15.

Utilize twin shaft laser remote sensing instrument ground detection provided by the invention and scaling system to obtain the method for measured laser remote sensing instrument detectivity, comprise following operation steps:

Step 1: the pulsed laser 13 of measured laser remote sensing instrument sends pulse laser, pulse laser is collimated after beam-expanding system 12 collimator and extenders, through beam splitter 1, is divided into two parts;

Step 2: wherein a part of pulse laser enters total reflective mirror 8 after 9 refractions of large-aperture long-focus parallel light tube, by total reflective mirror 8 reflect laggard enter on beam quality analyser 10 photosurfaces, form Emission Lasers hot spot, the far field beam quality that beam quality analysis instrument 10 these Emission Lasers hot spots of collection obtain measured laser remote sensing instrument distributes;

Step 3: another part pulse laser is converted to electric signal through reflecting into into photoelectric commutator 2 of beam splitter 1, after the time delay of chronotron 3, trigger again optical fiber output laser 4, optical fiber output laser 4 is exported the pulse laser after automatically controlled fibre optic attenuator 6 is decayed by optical fiber 5 by the other end of optical fiber 5, pulse laser becomes directional light through large-aperture long-focus parallel light tube 9, wherein a part of directional light is after 180 ° of reflections of prism of corner cube 11 again on the photosurface by directive beam quality analysis instrument 10 after the transmission of large-aperture long-focus parallel light tube 9 and the reflection of total reflective mirror 8, form analogue echo hot spot, and another part directional light enters measured laser remote sensing instrument as remote analogue echo and is received by receiving telescope 14, after signal processing circuit 15 is processed and provide output signal,

Step 4: the position of comparing Emission Lasers hot spot and analogue echo hot spot by beam quality analysis instrument 10, adjust the relative position of measured laser remote sensing instrument and laser remote sensing instrument ground detection and scaling system, Emission Lasers hot spot and analogue echo hot spot are overlapped on beam quality analysis instrument 10, realize measured laser remote sensing instrument and dock with the light path of scaling system with laser remote sensing instrument ground detection;

Step 5: until the light path of measured laser remote sensing instrument and laser remote sensing instrument ground detection and scaling system to after connecting, adjust the attenuation multiple of automatically controlled fibre optic attenuator 6, make the output signal of measured laser remote sensing instrument reach detection limit, utilize energy meter detection fiber output laser 4 to export energy value, and according to automatically controlled fibre optic attenuator 6 attenuation multiple values, obtain the minimum detectable energy values P of laser remote sensing instrument _rmin, according to formula 1, obtain the detectivity of measured laser remote sensing instrument:

$R_{\max }={\left(\frac{{\mathrm{KP}}_t{\mathrm{\τ}}_0{\mathrm{\τ}}^2{A}_r\mathrm{\σ}}{{\mathrm{\π}}^2{\mathrm{\θ}}_t^2{P}_{r\min }}\right)}^{\frac{1}{4}}---\left(1\right)$

In formula, R _maxbe that the observable maximum distance of laser remote sensing instrument is detectivity, K is that the beam quality being recorded by beam quality analysis instrument 10 distributes, P _toptical fiber output laser 4 output powers, τ ₀be optical system efficiency, τ is measured laser remote sensing instrument to laser atmospheric transmittance in target range, the radar cross section that σ is detected target, A _rreceiving optics aperture area, θ _tutilizing emitted light beam divergence angle, P _rminbeing the minimum detectable power of laser distance measuring system, is also system detection sensitivity.

Utilize twin shaft laser remote sensing instrument ground detection provided by the invention and scaling system to obtain the method for the measured laser remote sensing instrument geometry factor, comprise following operation steps:

Step 1: the pulsed laser 13 of measured laser remote sensing instrument sends pulse laser, pulse laser is collimated after beam-expanding system 12 collimator and extenders, through beam splitter 1, is divided into two parts;

Step 2: wherein a part of pulse laser enters total reflective mirror 8 after 9 refractions of large-aperture long-focus parallel light tube, by total reflective mirror 8 reflect laggard enter on beam quality analyser 10 photosurfaces, form Emission Lasers hot spot, the far field beam quality that beam quality analysis instrument 10 these Emission Lasers hot spots of collection obtain measured laser remote sensing instrument distributes;

Step 3: another part pulse laser is converted to electric signal through reflecting into into photoelectric commutator 2 of beam splitter 1, after the time delay of chronotron 3, trigger again optical fiber output laser 4, optical fiber output laser 4 is exported the pulse laser after automatically controlled fibre optic attenuator 6 is decayed by optical fiber 5 by the other end of optical fiber 5, pulse laser becomes directional light through large-aperture long-focus parallel light tube 9, wherein a part of directional light is after 180 ° of reflections of prism of corner cube 11 again on the photosurface by directive beam quality analysis instrument 10 after the transmission of large-aperture long-focus parallel light tube 9 and the reflection of total reflective mirror 8, form analogue echo hot spot, and another part directional light enters measured laser remote sensing instrument as remote analogue echo and is received by receiving telescope 14, after signal processing circuit 15 is processed and provide output signal,

Step 4: the position of comparing Emission Lasers hot spot and analogue echo hot spot by beam quality analysis instrument 10, adjust the relative position of measured laser remote sensing instrument and laser remote sensing instrument ground detection and scaling system, Emission Lasers hot spot and analogue echo hot spot are overlapped on beam quality analysis instrument 10, realize laser remote sensing instrument and dock with the light path of scaling system with laser remote sensing instrument ground detection;

Step 5: the position of optical fiber 5 other end end faces while utilizing two-dimensional movement platform 7 to record measured laser remote sensing instrument and laser remote sensing instrument ground detection and scaling system to achieve a butt joint, is recorded as (L ₀, 0); By two-dimensional movement platform 7, control optical fiber 5 other end end faces moves horizontally on long-focus heavy caliber parallel light tube 9 focal planes, monitor measured laser remote sensing instrument output signal situation simultaneously, the position of two-dimensional movement platform 7 when recording laser remote sensing instrument output signal becomes critical point, the shift position of two-dimensional movement platform 7 is with respect to (L ₀, 0) and its two-dimensional movement position is designated as (L _l, 0) and (L _r, 0); By two-dimensional movement platform 7, control optical fiber 5 other end end faces vertically moves on long-focus heavy caliber parallel light tube 9 focal planes, monitor measured laser remote sensing instrument output signal situation simultaneously, the position of two-dimensional movement platform 7 when recording laser remote sensing instrument output signal becomes critical point, the shift position of two-dimensional movement platform 7 is with respect to (L ₀, 0) and its two-dimensional movement position is designated as (L _u, 0) and (L _d, 0); According to formula (2), obtain the measured laser remote sensing instrument geometry factor, also claim geometric overlap factor:

${\mathrm{\δ}}_1=\frac{L_L+L_R}{2f}-\frac{L_0}{f}$ ${\mathrm{\δ}}_2=\frac{L_U+L_D}{2f}-\frac{L_0}{f}---\left(2\right)$

In formula (2), f is the focal length of large-aperture long-focus parallel light tube 9, δ ₁for the tested laser remote sensing instrument geometry factor in the horizontal direction, δ ₂for the geometry factor of tested laser remote sensing instrument in the vertical direction.

The present invention adopt analogue echo generator and large-aperture long-focus parallel light tube 9 to produce to have orientation can accurately be controlled and demarcation, energy can fine adjustment, bigbore remote analogue echo.The orientation of this analogue echo can be controlled and demarcate by two-dimensional movement platform 7 is accurate, and the energy of this analogue echo is controlled by automatically controlled fibre optic attenuator 6.Utilize the actual detection state that this remote analogue echo can simulated laser radar, the far field beam quality that can obtain exactly measured laser remote sensing instrument distributes and detectivity, and can obtain exactly the geometry factor of measured laser remote sensing instrument, to solve spaceborne instrument before and after the experiment of experience various temperature, hot vacuum environment, the geometry factor changes and a difficult problem that cannot Accurate Calibration.Utilize laser remote sensing instrument ground detection of the present invention and scaling system to survey measured laser radar, the detectivity that draws measured laser radar is 18.9km.The calibration uncertainty < 5% of the present invention to detectivity, to the calibration uncertainty < 20urad of the geometry factor.

Claims (3)

1. twin shaft laser remote sensing instrument ground detection and scaling system, is characterized in that: comprise analogue echo generator, two-dimensional movement platform (7), large-aperture long-focus parallel light tube (9) and beam quality analysis instrument (10); One side of large-aperture long-focus parallel light tube (9) is provided with beam splitter (1) and prism of corner cube (11), and opposite side is provided with total reflective mirror (8); Described analogue echo generator is comprised of photoelectric commutator (2), chronotron (3), optical fiber output laser (4), optical fiber (5) and automatically controlled fibre optic attenuator (6); Photoelectric commutator (2) and chronotron (3) are positioned between beam splitter (1) and optical fiber output laser (4), beam splitter (1) is for the pulse laser being sent by measured laser remote sensing instrument is divided into two parts, and wherein a part of pulse laser reflects to photoelectric commutator (2); Photoelectric commutator (2) is for being converted to electric signal by the pulse laser of beam splitter (1) reflection; Chronotron (3) is for the time delay of electric signal; Optical fiber output laser (4) for exporting pulse laser after being triggered by the electric signal after time delay, optical fiber output laser (4) is connected with one end of optical fiber (5), the other end of optical fiber (5) is positioned at the opposite side of large-aperture long-focus parallel light tube (9), the port of optical fiber (5) other end is positioned on the focal plane of large-aperture long-focus parallel light tube (9), and is fixed on two-dimensional movement platform (7); Automatically controlled fibre optic attenuator (6) is arranged on optical fiber (5); The photosurface of beam quality analysis instrument (10) is placed on large-aperture long-focus parallel light tube (9) by the focal plane of total reflective mirror (8) reflection.

2. utilize twin shaft laser remote sensing instrument ground detection described in claim 1 and scaling system to obtain the method for measured laser remote sensing instrument detectivity, it is characterized in that:

The structure of this system is: comprise analogue echo generator, two-dimensional movement platform (7), large-aperture long-focus parallel light tube (9) and beam quality analysis instrument (10); One side of large-aperture long-focus parallel light tube (9) is provided with beam splitter (1) and prism of corner cube (11), and the opposite side of large-aperture long-focus parallel light tube (9) is provided with total reflective mirror (8); Described analogue echo generator is comprised of photoelectric commutator (2), chronotron (3), optical fiber output laser (4), optical fiber (5) and automatically controlled fibre optic attenuator (6); Photoelectric commutator (2) and chronotron (3) are positioned between beam splitter (1) and optical fiber output laser (4), beam splitter (1) is for the pulse laser being sent by measured laser remote sensing instrument is divided into two parts, and wherein a part of pulse laser reflects to photoelectric commutator (2); Photoelectric commutator (2) is for being converted to electric signal by the pulse laser of beam splitter (1) reflection; Chronotron (3) is for the time delay of electric signal; Optical fiber output laser (4) for exporting pulse laser after being triggered by the electric signal after time delay, optical fiber output laser (4) is connected with one end of optical fiber (5), the other end of optical fiber (5) is positioned at the opposite side of large-aperture long-focus parallel light tube (9), the port of optical fiber (5) other end is positioned on the focal plane of large-aperture long-focus parallel light tube (9), and is fixed on two-dimensional movement platform (7); Automatically controlled fibre optic attenuator (6) is arranged on optical fiber (5); The photosurface of beam quality analysis instrument (10) is placed on large-aperture long-focus parallel light tube (9) by the focal plane of total reflective mirror (8) reflection;

Utilize said system to implement according to following steps:

Step 1: measured laser remote sensing instrument sends pulse laser, pulse laser is divided into two parts through beam splitter (1);

Step 2: wherein a part of pulse laser enters total reflective mirror (8) after large-aperture long-focus parallel light tube (9) refraction, by total reflective mirror (8) reflect laggard enter on beam quality analyser (10) photosurface, form Emission Lasers hot spot, beam quality analysis instrument (10) gathers the far field beam quality that this Emission Lasers hot spot obtains measured laser remote sensing instrument and distributes;

Step 3: another part pulse laser is converted to electric signal through reflecting into into photoelectric commutator (2) of beam splitter (1), after the time delay of chronotron (3), trigger again optical fiber output laser (4), optical fiber output laser (4) is exported the pulse laser after automatically controlled fibre optic attenuator (6) decay by optical fiber (5) by the other end of optical fiber (5), pulse laser becomes directional light through large-aperture long-focus parallel light tube (9), wherein a part of directional light is after 180 ° of reflections of prism of corner cube (11) again on the photosurface by directive beam quality analysis instrument (10) after the transmission of large-aperture long-focus parallel light tube (9) and the reflection of total reflective mirror (8), form analogue echo hot spot, and another part directional light enters measured laser remote sensing instrument and provides output signal as remote analogue echo,

Step 4: by relatively Emission Lasers hot spot and analogue echo facula position of beam quality analysis instrument (10), adjust the relative position of measured laser remote sensing instrument and laser remote sensing instrument ground detection and scaling system, make Emission Lasers hot spot and analogue echo hot spot in the upper coincidence of beam quality analysis instrument (10), realize laser remote sensing instrument and dock with the light path of scaling system with laser remote sensing instrument ground detection;

Step 5: until the light path of measured laser remote sensing instrument and laser remote sensing instrument ground detection and scaling system to after connecting, adjust the attenuation multiple of automatically controlled fibre optic attenuator (6), make the output signal of measured laser remote sensing instrument reach detection limit, utilize energy meter detection fiber output laser (4) output energy value, and according to automatically controlled fibre optic attenuator (6) attenuation multiple value, obtain the minimum detectable power P of laser remote sensing instrument _rmin, according to formula (1), obtain the detectivity of laser remote sensing instrument:

$R_{\max }={\left(\frac{{\mathrm{KP}}_t{\mathrm{\&tau;}}_0{\mathrm{\&tau;}}^2{A}_r\mathrm{\&sigma;}}{{\mathrm{\&pi;}}^2{\mathrm{\&theta;}}_t^2{P}_{r\min }}\right)}^{\frac{1}{4}}---\left(1\right)$

In formula, R _maxbe that the observable maximum distance of laser remote sensing instrument is detectivity, K is that the beam quality being recorded by beam quality analysis instrument (10) distributes, P _toptical fiber output laser (4) output power, τ ₀be optical system efficiency, τ is measured laser remote sensing instrument to laser atmospheric transmittance in target range, the radar cross section that σ is detected target, A _rreceiving optics aperture area, θ _tutilizing emitted light beam divergence angle, P _rminbeing the minimum detectable power of laser distance measuring system, is also system detection sensitivity.

3. utilize twin shaft laser remote sensing instrument ground detection described in claim 1 and scaling system to obtain the method for the measured laser remote sensing instrument geometry factor, it is characterized in that:

The structure of this system is: comprise analogue echo generator, two-dimensional movement platform (7), large-aperture long-focus parallel light tube (9) and beam quality analysis instrument (10); One side of large-aperture long-focus parallel light tube (9) is provided with beam splitter (1) and prism of corner cube (11), and the opposite side of large-aperture long-focus parallel light tube (9) is provided with total reflective mirror (8); Described analogue echo generator is comprised of photoelectric commutator (2), chronotron (3), optical fiber output laser (4), optical fiber (5) and automatically controlled fibre optic attenuator (6); Photoelectric commutator (2) and chronotron (3) are positioned between beam splitter (1) and optical fiber output laser (4), beam splitter (1) is for the pulse laser being sent by measured laser remote sensing instrument is divided into two parts, and wherein a part of pulse laser reflects to photoelectric commutator (2); Photoelectric commutator (2) is for being converted to electric signal by the pulse laser of beam splitter (1) reflection; Chronotron (3) is for the time delay of electric signal; Optical fiber output laser (4) for exporting pulse laser after being triggered by the electric signal after time delay, optical fiber output laser (4) is connected with one end of optical fiber (5), the other end of optical fiber (5) is positioned at the opposite side of large-aperture long-focus parallel light tube (9), the port of optical fiber (5) other end is positioned on the focal plane of large-aperture long-focus parallel light tube (9), and is fixed on two-dimensional movement platform (7); Automatically controlled fibre optic attenuator (6) is arranged on optical fiber (5); The photosurface of beam quality analysis instrument (10) is placed on large-aperture long-focus parallel light tube (9) by the focal plane of total reflective mirror (8) reflection;

Utilize said system to implement according to following steps:

Step 1: measured laser remote sensing instrument sends pulse laser, pulse laser is divided into two parts through beam splitter (1);

Step 2: wherein a part of pulse laser enters total reflective mirror (8) after large-aperture long-focus parallel light tube (9) refraction, by total reflective mirror (8) reflect laggard enter on beam quality analyser (10) photosurface, form Emission Lasers hot spot, beam quality analysis instrument (10) gathers the far field beam quality that this Emission Lasers hot spot obtains measured laser remote sensing instrument and distributes;

Step 3: another part pulse laser is converted to electric signal through reflecting into into photoelectric commutator (2) of beam splitter (1), after the time delay of chronotron (3), trigger again optical fiber output laser (4), optical fiber output laser (4) is exported the pulse laser after automatically controlled fibre optic attenuator (6) decay by optical fiber (5) by the other end of optical fiber (5), pulse laser becomes directional light through large-aperture long-focus parallel light tube (9), wherein a part of directional light is after 180 ° of reflections of prism of corner cube (11) again on the photosurface by directive beam quality analysis instrument (10) after the transmission of large-aperture long-focus parallel light tube (9) and the reflection of total reflective mirror (8), form analogue echo hot spot, and another part directional light enters measured laser remote sensing instrument and provides output signal as remote analogue echo,

Step 4: by relatively Emission Lasers hot spot and analogue echo facula position of beam quality analysis instrument (10), adjust the relative position of measured laser remote sensing instrument and laser remote sensing instrument ground detection and scaling system, make Emission Lasers hot spot and analogue echo hot spot in the upper coincidence of beam quality analysis instrument (10), realize laser remote sensing instrument and dock with the light path of scaling system with laser remote sensing instrument ground detection;

Step 5: the position of optical fiber (5) other end end face while utilizing two-dimensional movement platform (7) to record measured laser remote sensing instrument and laser remote sensing instrument ground detection and scaling system to achieve a butt joint, is recorded as (L ₀, 0); By two-dimensional movement platform (7), control optical fiber (5) other end end face moves horizontally on long-focus heavy caliber parallel light tube (9) focal plane, monitor measured laser remote sensing instrument output signal situation simultaneously, the position of two-dimensional movement platform (7) when recording laser remote sensing instrument output signal becomes critical point, the shift position of two-dimensional movement platform (7) is with respect to (L ₀, 0) and its two-dimensional movement position is designated as (L _l, 0) and (L _r, 0); By two-dimensional movement platform (7), control optical fiber (5) other end end face vertically moves on long-focus heavy caliber parallel light tube (9) focal plane, monitor measured laser remote sensing instrument output signal situation simultaneously, the position of two-dimensional movement platform when recording laser remote sensing instrument output signal becomes critical point, the shift position of two-dimensional movement platform (7) is with respect to (L ₀, 0) and its two-dimensional movement position is designated as (L _u, 0) and (L _d, 0); According to formula (2), obtain the laser remote sensing instrument geometry factor, also claim geometric overlap factor:

${\mathrm{\&delta;}}_1=\frac{L_L+L_R}{2f}-\frac{L_0}{f},{\mathrm{\&delta;}}_2=\frac{L_U+L_D}{2f}-\frac{L_0}{f}---\left(2\right)$

In formula (2), f is the focal length of large-aperture long-focus parallel light tube (9), δ ₁for the tested laser remote sensing instrument geometry factor in the horizontal direction, δ ₂for the geometry factor of tested laser remote sensing instrument in the vertical direction.

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