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WO2007036010A1 - Appareil de type lidar courte portee a reponse spatiale plate - Google Patents

Appareil de type lidar courte portee a reponse spatiale plate Download PDF

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Publication number
WO2007036010A1
WO2007036010A1 PCT/CA2005/001520 CA2005001520W WO2007036010A1 WO 2007036010 A1 WO2007036010 A1 WO 2007036010A1 CA 2005001520 W CA2005001520 W CA 2005001520W WO 2007036010 A1 WO2007036010 A1 WO 2007036010A1
Authority
WO
WIPO (PCT)
Prior art keywords
light
lidar
lidar apparatus
particles
scattered light
Prior art date
Application number
PCT/CA2005/001520
Other languages
English (en)
Inventor
François BABIN
Marc Levesque
Original Assignee
Institut National D'optique
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Institut National D'optique filed Critical Institut National D'optique
Priority to CA2628027A priority Critical patent/CA2628027C/fr
Priority to PCT/CA2005/001520 priority patent/WO2007036010A1/fr
Publication of WO2007036010A1 publication Critical patent/WO2007036010A1/fr

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S17/00—Systems using the reflection or reradiation of electromagnetic waves other than radio waves, e.g. lidar systems
    • G01S17/88—Lidar systems specially adapted for specific applications
    • G01S17/95—Lidar systems specially adapted for specific applications for meteorological use
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
    • G01S7/48—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S17/00
    • G01S7/481—Constructional features, e.g. arrangements of optical elements
    • G01S7/4816—Constructional features, e.g. arrangements of optical elements of receivers alone
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
    • G01S7/48—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S17/00
    • G01S7/481—Constructional features, e.g. arrangements of optical elements
    • G01S7/4818—Constructional features, e.g. arrangements of optical elements using optical fibres
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
    • Y02A90/00—Technologies having an indirect contribution to adaptation to climate change
    • Y02A90/10—Information and communication technologies [ICT] supporting adaptation to climate change, e.g. for weather forecasting or climate simulation

Definitions

  • the present invention relates to optical measuring devices and more particularly concerns a LIDAR apparatus with a flat spatial response used for measuring concentrations of particles at a short range.
  • LIDAR Light Detection And Ranging
  • a pulsed light signal is sent and is back-scattered by the particles.
  • a temporal and amplitude analysis of the back-scattered light determines the particle concentrations along the path of the emitted beam of light.
  • the scattering phenomena observed by such devices may be instantaneous or delayed according to fluorescent, luminescent or phosphorescent mechanism, and accompanied or not by a wavelength shift.
  • Most particle detection LIDARs are however designed and built for long ranges, usually for 200 meters or more. These highly coherent LIDARs use light beams with very small divergence and detectors with small diameters, of the order of less than 1 mm. This maximizes light collection from long distances (over 1 km) and reduces detection noise levels.
  • the major impairment of using standard LIDARs for short range applications is the Mi 2 dependence of the signal, r being the distance from the target to the receiving optics. For short distances, this entails a huge signal variation; a factor of 10000 (40 dB optical) between 1 m and 100 m, if all the light gathered by the receiving optics falls on the detector. This places stringent requirements on the detection electronics. Moreover, for iower cost operation, the temporal resolution is limited, usually between 10 and 20 nanoseconds, so that a data point represents the average density of aerosols in some volume covering 1.5 to 3 m along the path of the emitted beam.
  • the system's spatial response In order to have an accurate value of the average density, the system's spatial response must not vary significantly over the volume along the emitted beam over which the average is taken.
  • a short range LIDAR thus requires that the system response be practically constant over large distances, that is, distances larger than the system's spatial resolution.
  • LIDAR is practically constant over a distance equivalent to the system's resolution.
  • LIDAR spatial responses are covered in a number of scientific articles, for example:
  • LONNQVIST presents a method and apparatus for detecting particles at short range using a pair of detectors in a half-bridge, a beamsplitter and a common lens.
  • HUTTMANN describes a uniaxial system, somewhat like that of LONNQVIST, capable of short range measurements, but again, without equalization of the response.
  • Ht)TTMANN uses multiple fibers, but their purpose is not for equalization of the short range spatial response.
  • the present invention provides a LIDAR apparatus for measuring concentrations of particles with respect to a distance of these particles from the apparatus within a short range therefrom.
  • the apparatus has a substantially flat spatial response, whereby a same concentration of particles at any distance within the short range will generate a signal of substantially the same intensity.
  • the apparatus first includes a source optical arrangement projecting an excitation light beam along an optical path.
  • the excitation light beam is back-scattered by the particles within this optical path.
  • the apparatus further includes a light-collecting arrangement having a field of view intersecting the optical path along the short range.
  • the light-collecting arrangement includes light-receiving optics, receiving the back-scattered light, and a detector detecting the received back-scattered iight.
  • the Ifght-coiiecti ⁇ g arrangement further includes a spatial filter spatially filtering the back-scattered light so as to flatten the spatial response of the apparatus.
  • the present invention advantageously uses optical propagation after the light- receiving optics and detection geometry to render the response of a LIDAR as flat as possible with respect to distance, for short range detection such as from 1 m to less than 100 m or so.
  • This new class of particle detection LIDARs can be optimized for low cost, low weight, low power consumption, amongst other parameters.
  • FIG. 1 is a schematic representation of an apparatus according to a preferred embodiment of the invention.
  • FIG. 2 is a schematic representation of an apparatus according to another preferred embodiment of the invention.
  • FIGs. 3A to 3H shows the-spatial light distribution in a detecting plane for reflecting planes respectively at 1 m (FIG. 3A), 2 m (FIG. 3B), 4 m (FIG. 3C), 8 m (FIG. 3D), 15 m (FIG. 3E), 30 m (FIG. 3F), and 50 m (FIG. 3H).
  • FIG. 4 illustrates the profile of a mask according to one embodiment of the invention.
  • FIG. 5 is a graph illustrating the calculated spatial response of an apparatus according to an embodiment of the invention. DESCRIPTION OF PREFERRED EMBODIMENT OF THE INVENTION Referring to FIG. 1 , there is schematically illustrated a LIDAR apparatus 10 having an almost flat spatial response according to a preferred embodiment of the present invention.
  • the apparatus is intended for measuring, at short range, concentrations of particles 11 in the air such as aerosols, fog, dust, clouds of chemical droplets such as pesticides, insecticides or the like, or suspensions in a liquid medium, for example in the course of analyzing the turbidity of water in waste water settling tanks.
  • range is used herein as referring to the distance between the detected particles 11 and the apparatus 10 itself. It is understood that the designation of “short range” for the apparatus 10 of the invention is by comparison to traditional aerosol detecting LIDAR devices, which are designed to operate at a range of about 200 m or more; in the preferred embodiments, the apparatus 10 is designed to be operated within 100 m, preferably within 50 m. It will of course be understood by a person skilled in the art that the range of the apparatus also has a lower boundary close to the apparatus where the geometry of the system prevents the measure of particle concentrations. Typically, this boundary may for example be around 1 m from the apparatus.
  • the apparatus 10 first includes a source arrangement 12 projecting excitation light beam 14, which is preferably pulsed or otherwise modulated.
  • the source arrangement 12 may for example include aroued iaser source, such as typicai low cost sources used for range finders such as for example pulsed high power laser diodes 16 (such as those sold by OSRAM, Perkin-Elmer or Laser Components, for example), a pulsed fiber laser (such as those sold by INO 1 Keopsys, SPIOptics or OzOptics, for example), a pulsed solid state Q-switched ⁇ chip laser (such as those sold by JDS Uniphase, for example) or any other type of pulsed laser generating an appropriate light beam.
  • anoied iaser source such as typicai low cost sources used for range finders
  • pulsed high power laser diodes 16 such as those sold by OSRAM, Perkin-Elmer or Laser Components, for example
  • a pulsed fiber laser such as those sold by INO 1 Ke
  • the excitation beam 14 from the source is imaged on a diffuser 20 by an imaging lens 22; this is done in order to render the system eye safe, an important parameter for many short range LIDAR applications. Any other appropriate means may of course be used for such a purpose.
  • An output lens 18 images the light beam from the diffuser 20 along an optical path 19 traversing the target range of the apparatus 10.
  • scattering is used herein to refer in the large sense to the dispersal of the light beam by the particles as a result of physical interactions therewith.
  • the mechanisms involved may be instantaneous, as is the case for "true” scattering, or according to fluorescent, luminescent or phosphorescent phenomena.
  • the scattering may be without a wavelength change, or accompanied by a small wavelength shift. It will be clear to one skilled in the art that the data processing of the detected light will depend on the type of scattering observed.
  • the apparatus 10 further includes a light collecting arrangement 24 having a field of view intersecting the optical path 19 within the operation range of the apparatus. The light collecting arrangement 24 therefore receives the back-scattered light 25 within its field of view.
  • the light-collecting arrangement 24 includes a detector 26 and light-receiving optics.
  • the light-receiving optics may be embodied by any appropriate optical arrangement. In the illustrated embodiment, it includes an input lens 28 collecting the back-scattered light and propagating it towards at least one detecting plane D .
  • the distribution of light in any detecting plane varies depending on 1) its distance from the components of the light-collecting arrangement, 2) the elementary scattering volume, or mix of elementary scattering volumes, from which it originates and 3) on the degree of back-scattering from each scattering volume (in other words, in depends on the mix of particles and on their distribution within the excitation beam path).
  • the first factor is fixed for a given system, and the third factor contains the information to be measured by the apparatus.
  • the second factor will be greatly affected by the spatial response of the apparatus, and this effect must be taken into account for the information measured to be significant.
  • the problematic is best understood through an example.- Let us suppose the spatial resolution of the apparatus is 2 m, that is, it is impossible to determine from where a light signal originates within a 2 m long interval along the optical path. At short range, for example between 2 m and 4 m, it is impossible to distinguish between a signal produced by 4000 particles all located in a 1 mm slice around 2 m and a signal produced by 16000 particles in a 1 mm slice around 4 m. If all the light falling on the light collecting arrangement is detected, both signals will be the same, and yet the actual concentrations of particles differ by a factor of 4. In order to take these short range effects into consideration and obtain accurate concentration values, the relative intensity of light received from each volume Rj if the particle concentration was constant along the optical path has to be tailored.
  • FIGs. 3A to 3H This relative intensity is for example illustrated in FIGs. 3A to 3H, which shows the light distributions in a same detecting plane for different scattering volumes (at different distances from the light collecting arrangement).
  • the source is a laser diode imaged 50 m away from the apparatus.
  • a scattering target is placed at planes respectively at 1 m, 2 m, 4 m, 8 m, 15 m, 30 m and 50 m from the apparatus, and the resulting back-scattered light is detected in a detection plane at 208 mm from the back of the input lens, which in this case has a 202 mm back focal length. Only the light falling on a 6 mm x 6 mm surface is shown.
  • the back-scattered light therefore corresponds to the signal which would originate from different elementary scattering volumes Ri (replaced in this case by scattering surfaces, which is equivalent) within the operation range, all with the same concentration of particles (or the same back-scattering coefficient for the scattering surface).
  • the image from the 50 m reflecting surface (FIG. 3H) is sharp and has substantially the same dimensions as the effective source. Light distributions gathered from other reflecting surfaces are offset from the distribution at 50 m and become larger and larger as the originating surface comes closer to the lenses.
  • the light-collecting arrangement 24 of the apparatus 10 includes a spatial filter, spatially filtering the back-scattered light 25 to flatten the spatial response of the apparatus.
  • spatially filtering it is meant that portions of the light incident on one or more detecting planes is blocked so that only selected portions of the back scattered light 25 is provided to the detector 26. These portions are selected in order for the spatial response of the apparatus to be substantially flat, that is, that a same concentration of particles at any distance within the operation range would generate a signal of substantially the same intensity.
  • the spatial filter may be embodied by any reflective, refractive or diffractive component or combination thereof accomplishing the desired spatial shaping of the back-scattered light.
  • the spatial filter is embodied by a mask 30 disposed along the detecting plane D.
  • the mask 30 preferably has openings therein which allow the above-mentioned selected portions of the back- scattered light therethrough. Alternatively, it may be used in reflection, in which case it may include reflecting and non-reflecting portions thereon defining the filter. In the preferred embodiment, these openings will accept all or a substantial portion of the light from the scattering volume at 50 m from the apparatus, and much less of the light from the scattering volume at 1 m.
  • the proportion of light accepted from 1 m is preferably close to 10000 times smaller than at 50 m, in order to account for the 1 /A 2 dependence.
  • FIG. 4 A possible shape for the mask 30 is shown in FIG. 4.
  • the shape accepts the right amount of light from each scattering volume along the optical path of the excitation beam so as to render the system response as flat as possible.
  • a corresponding calculated response is shown in FIG. 5.
  • the obtained response is substantially flat, sufficiently in any event for the needs of most short range applications.
  • a great number of possible mask profiles could be used to provide the desired result.
  • the light distributions in the plane of the mask should preferably be known for a number of reflecting surfaces along the optical path of the emitted beam.
  • the light distributions can be deduced from simulations using optical design software or, preferably, they can be directly measured, for example with a pinhole and detector or with a digital camera. In this latter case, an appropriate optically scattering target is placed at different distances from the emitting lens. A measurement is done for each target distance, by moving the pinhole-detector pair in the mask plane or by acquiring a digital image with the camera detector in the mask plane.
  • computer software may be used to compute the spatial response for a number of different intuitively determined mask geometries until an i i
  • the mask is then fabricated with an appropriate technique (such a laser micro-machining), tested and optimized.
  • the detector 26 is seen disposed behind the mask 30 and accepts the portions of the scattered light transmitted by this mask.
  • the size of the detector is preferably adapted to the size, shape and configuration of the spatial filter. In this preferred embodiment, the detector 26 is larger than the mask 30.
  • Light impinging on the detector 26 generates an electronic signal that is preferably amplified and digitized in processing electronics 32.
  • the processing electronics 32 should have sufficient bandwidth for the purpose and digitization is done in a proper manner.
  • Various possible hardware and software apt to embody the processing electronics 32 are well known in the art and need not be described further.
  • the result is a set of data points spaced by a time interval corresponding to a distance interval, each data point representing the amount of light back- scattered by a given volume at the data point location.
  • the apparatus 10 is preferably provided in a casing 34 optically isolating its various components.
  • the source arrangement 12 and light-collecting arrangement 24 are preferably optically isolated from each other by a panel 36.
  • the source arrangement 12 includes a large core optical fiber 42 to which the laser diode 16 is butt coupled.
  • the optical fiber core has an output 44 which defines a round and uniform source of light. This output 44 is imaged, with output lens 18, at a distance of the apparatus 10 generally corresponding to its operating range (preferably between 50 and 100 m).
  • the spatial filter is embodied by a plurality of waveguides such as, but not limited to, optical fibers 38, each having an input 40 positioned on one of the detecting planes and an output 41 coupled to the detector 26.
  • the inputs 40 of the fibers 38 are strategically distributed so as to collectively receive the appropriate portions of back-scattered light 25 according to the principle explained above.
  • This ensemble of optical waveguides will therefore preferably accept light in order to compensate for the 1/r 2 dependence; for example, it will detect all of the light collected from a target scattering volume or surface at 50 m (or another end-of-range target) and much less of the light from the same target at 1 m or less.
  • the ensemble should accept the right amount of light from any scattering volume so as to render the system response as flat as possible.
  • the inputs 40 of the optical fibers 38 are preferably in the same detecting plane D, but not necessarily. When it is the case, the fibers 38 should all have the same length in order not to distort the time response of the system. The captured portions of the back-scattered light will be guided to reach the detector 26.
  • the embodiment of FIG. 2 allows a gain of flexibility in the positioning of the detector and associated electronics.
  • the use of a much smaller detector area improves the signal to noise ratio and lowers the cost of the detector.
  • FIGs. 1 and 2 need not be necessarily used in the illustrated combinations.
  • the source optical arrangement of FIG. 2 may be used with the light-collecting arrangement of FIG. 1 , and vice versa.
  • the present invention provides a useful LIDAR apparatus for detecting particles and measuring substantially accurate concentrations within a shorter range than traditional aerosol detecting LIDARs.
  • one advantage of some of the embodiments of the invention is the reduction of the signal from longer distances than those targeted by the apparatus.
  • the mask can be shaped to receive aii of the iight from 50 m, but light from iOO m could be reduced by more than the 1/r 2 dependence, and this reduction could be larger for larger distances between the axes of the output and input lenses.
  • the apparatus of the present invention can be used to render only a part of the spatial response flat, the other parts falling more or less rapidly to a much lower level.
  • the spatial response can be tailored to the needs of a given application.
  • these LIDARs could be scanned to form 3-D plots of aerosol, suspension and other particle concentrations.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • General Physics & Mathematics (AREA)
  • Radar, Positioning & Navigation (AREA)
  • Remote Sensing (AREA)
  • Electromagnetism (AREA)
  • Optical Radar Systems And Details Thereof (AREA)
  • Investigating Or Analysing Materials By Optical Means (AREA)

Abstract

L'invention concerne un appareil de type LIDAR à réponse spatiale plate permettant de détecter des particules à courte portée. Ledit appareil comprend une source de lumière projetant un faisceau lumineux rétrodiffusé par les particules à détecter. La lumière rétrodiffusée est reçue, détectée et analysée. Un filtre spatial filtre spatialement la lumière rétrodiffusée reçue afin d'aplanir la réponse de l'appareil, de sorte qu'une même concentration de particules à une distance quelconque dans la courte portée générera un signal sensiblement de la même intensité. On obtient ce résultat, par exemple, par disposition d'un masque correctement profilé devant un détecteur ou une pluralité de guides d'onde spatialement distribués. De ce fait, l'appareil de type LIDAR peut corriger le 1/r2 ou d'autres dépendances de la lumière rétrodiffusée sur la distance r.
PCT/CA2005/001520 2005-09-30 2005-09-30 Appareil de type lidar courte portee a reponse spatiale plate WO2007036010A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
CA2628027A CA2628027C (fr) 2005-09-30 2005-09-30 Appareil de type lidar courte portee a reponse spatiale plate
PCT/CA2005/001520 WO2007036010A1 (fr) 2005-09-30 2005-09-30 Appareil de type lidar courte portee a reponse spatiale plate

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/CA2005/001520 WO2007036010A1 (fr) 2005-09-30 2005-09-30 Appareil de type lidar courte portee a reponse spatiale plate

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8390791B2 (en) 2009-11-30 2013-03-05 General Electric Company Light detection and ranging system
US10679530B1 (en) 2019-02-11 2020-06-09 Toyota Motor Engineering & Manufacturing North America, Inc. Systems and methods for mobile projection in foggy conditions

Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4052600A (en) * 1975-01-06 1977-10-04 Leeds & Northrup Company Measurement of statistical parameters of a distribution of suspended particles
US4245909A (en) * 1978-06-26 1981-01-20 Loos Hendricus G Optical instrument for measurement of particle size distributions
US4338030A (en) * 1978-06-26 1982-07-06 Loos Hendricus G Dispersive instrument for measurement of particle size distributions
JPS5838864A (ja) * 1981-08-31 1983-03-07 Shimadzu Corp 浮遊粒子速度計
JPS62106347A (ja) * 1985-11-05 1987-05-16 Shimadzu Corp 粒子分析装置の光源変動補正方法
CA2000049A1 (fr) * 1988-10-05 1990-04-05 Christian Werner Dispositif lidar servant a mesurer les turbidites atmospheriques
US5116124A (en) * 1988-09-08 1992-05-26 Vaisala Oy Measurement system for scattering of light
US5241315A (en) * 1992-08-13 1993-08-31 The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration Micro pulse laser radar
WO1994029762A1 (fr) * 1993-06-04 1994-12-22 Coulter Corporation Appareil et procede de mesure de la taille de particules par diffraction laser
US5859705A (en) * 1993-05-26 1999-01-12 The Dow Chemical Company Apparatus and method for using light scattering to determine the size of particles virtually independent of refractive index
US5880836A (en) * 1994-01-11 1999-03-09 Vaisala Oy Apparatus and method for measuring visibility and present weather
CA2437897A1 (fr) * 2001-02-09 2002-08-22 Commonwealth Scientific And Industrial Research Organisation Systeme et procede base sur le lidar

Patent Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4052600A (en) * 1975-01-06 1977-10-04 Leeds & Northrup Company Measurement of statistical parameters of a distribution of suspended particles
US4245909A (en) * 1978-06-26 1981-01-20 Loos Hendricus G Optical instrument for measurement of particle size distributions
US4338030A (en) * 1978-06-26 1982-07-06 Loos Hendricus G Dispersive instrument for measurement of particle size distributions
JPS5838864A (ja) * 1981-08-31 1983-03-07 Shimadzu Corp 浮遊粒子速度計
JPS62106347A (ja) * 1985-11-05 1987-05-16 Shimadzu Corp 粒子分析装置の光源変動補正方法
US5116124A (en) * 1988-09-08 1992-05-26 Vaisala Oy Measurement system for scattering of light
CA2000049A1 (fr) * 1988-10-05 1990-04-05 Christian Werner Dispositif lidar servant a mesurer les turbidites atmospheriques
US5241315A (en) * 1992-08-13 1993-08-31 The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration Micro pulse laser radar
US5859705A (en) * 1993-05-26 1999-01-12 The Dow Chemical Company Apparatus and method for using light scattering to determine the size of particles virtually independent of refractive index
WO1994029762A1 (fr) * 1993-06-04 1994-12-22 Coulter Corporation Appareil et procede de mesure de la taille de particules par diffraction laser
US5880836A (en) * 1994-01-11 1999-03-09 Vaisala Oy Apparatus and method for measuring visibility and present weather
CA2437897A1 (fr) * 2001-02-09 2002-08-22 Commonwealth Scientific And Industrial Research Organisation Systeme et procede base sur le lidar

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8390791B2 (en) 2009-11-30 2013-03-05 General Electric Company Light detection and ranging system
US10679530B1 (en) 2019-02-11 2020-06-09 Toyota Motor Engineering & Manufacturing North America, Inc. Systems and methods for mobile projection in foggy conditions

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CA2628027C (fr) 2013-04-23
CA2628027A1 (fr) 2007-04-05

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