| US 7,548,367 B2 | ||
| Laser active optronic system with improved detectivity | ||
| Michel Papuchon, Villebon/Yvette (France); and Jean-Paul Pocholle, La Norville (France) | ||
| Assigned to Thales, (France) | ||
| Appl. No. 10/582,713 PCT Filed Dec. 09, 2004, PCT No. PCT/EP2004/053370 § 371(c)(1), (2), (4) Date Jun. 12, 2006, PCT Pub. No. WO2005/066653, PCT Pub. Date Jul. 21, 2005. |
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| Claims priority of application No. 03 14602 (FR), filed on Dec. 12, 2003. | ||
| Prior Publication US 2007/0110435 A1, May 17, 2007 | ||
| Int. Cl. H01S 3/102 (2006.01); G02B 26/10 (2006.01) | ||
| U.S. Cl. 359—333 [356/318; 372/38.02; 372/38.03; 372/38.06; 372/38.1] | 17 Claims |
| 1. A laser active optronic system, comprising:
an emission channel for the emission by an emission source of a laser beam illuminating a target,
a receiving channel for receiving a backscattering wave backscattered by the target, and
a switching device positioned in the receiving channel, wherein said switching device is an optical switching device controlled
by a control unit, said control unit activating the switching device into an ON mode at a predetermined instant after the
start of emission of the illuminating laser beam, so that the backscattering wave passes through at least one temporal window
for a predetermined duration, and wherein the switching device is in an OFF mode at least until said predetermined instant,
so as to suppress part of a parasitic light flux incident in the reception channel and
wherein the optical device comprises an optical gain medium and pumping means for pumping said gain medium, said optical gain
medium being absorbent at the wavelength of the laser when not pumped, and the switching device is in the OFF mode, and becoming
substantially transparent when the laser is pumped, and the switching device is in the ON mode.
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