Home » Emerging Technologies » Polarization and MFOV lidar measurements with a gated-ICCD camera
Polarization and MFOV lidar measurements with a gated-ICCD camera
STATUS
Research Prototype
AVAILABILITY
No instrument are available.
REQUEST PROCEDURE
The technologies have been developed during a contract for the DRDC-Valcartier in Quebec city (Canada). An arrangement with this institution should be request before to use the technology for NCAR research project.
Emerging Technologies
A clear azimuthal pattern in the recorded images can be observed when we measure the cross-polarized backscattered light from a linearly polarized laser beam penetrating a cloud made of spherical particles with a gated intensified CCD camera. This pattern originates from second order scattering, and this is the higher-order scattering that causes blurring with the increasing of the optical depth. The contrast of the symmetrical features can be related to the measure of the optical depth. Moreover, by identifying and subtracting the blurring contributions, the resulting pattern provides a “pure” second-order scattering measurement that can be used for the retrieval of droplet size. Also, with a single gated intensified CCD camera it is possible to investigate the influence of multiple scattering on lidar depolarization measurements using the results of simultaneous azimuthally resolved multiple-field-of-view (MFOV) measurements in both polarization states (parallel polarization and cross-polarization). As the contribution of multiple scattering to the lidar return signal increases, an increase of the depolarization ratio (δ) can be observed. The δ recorded in the direction parallel to the polarization direction of the laser or to its complementary angle originates from higher scattering order and it is possible to establish an experimental relationship between this parameter and the optical depth.
CONTACT
Nathalie Roy
Lidarcam
3154 Bernadet Quebec, Qc Canada G2A 1H1
1-418-842-5258
nathalieroy_phy@hotmail.com
SPECIFICATIONS
Developer
Development SectorFed/State Gov
R&D ProgramYes
Years Till Available<3
Investment Required<$100k
Projected Applicationlidar polarization measurement
Unit CostN/A
Key RisksAvailability of sensor in the wavelength band studied
Ease of Usesingle operator
PlatformsGround
Ship
Space
TRLTRL 6
REFERENCES
N. Roy, G. Roy, « Influence of Multiple Scattering on Lidar Depolarization Measurements with an ICCD Camera», 23 th International Laser Radar Conference, Nara, Japan, July 2006. N. Roy, G. Roy, L. R. Bissonnette, «Influence of Multiple Scattering on Lidar Depolarization Measurements with an ICCD camera», in 14th International Workshop on Lidar Multiple Scattering Experiments, edited by Defence R&D Canada – Valcartier, Proceeding of SPIE, 17-26, 2006. N. Roy and al., «Lidar depolarization asymmetry measurements and its relation with the optical depth», in 13th International Workshop on Lidar Multiple Scattering Experiments, edited by Anatoli G. Borovoi, Proceeding of SPIE Vol. 5829 (SPIE, Bellingham, WA, 2005), 208-219. N. Roy and al., «Measurement of the azimuthal dependence of cross-polarized lidar returns and its relation with optical depth», 22 th International Laser Radar Conference, Matera, Italia, July 2004. N. Roy, G. Roy, L. R. Bissonnette, J-R Simard, «Measurement of the azimuthal dependence of cross-polarized lidar returns and its relation with optical depth», Appl. Opt. vol.43 no 13 (2004).
UPDATED ON
28 Sep 2009 16:07