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Laser stealth method of optical system

In order to protect optical system from being discovered by the active laser reconnaissance, the unsymmetrical covering method is proposed to realize the optical system's laser stealth. The theoretical model of the method was established. The laser stealth effect was analyzed and the results indicate that covering a part of optical system's aperture could obscure the echo in both the covered area and its centrosymmetric area. Therefore, the absolute laser stealth could be achieved by covering half of the optical system's aperture, while the optical system still has good performance. An experiment was designed to validate the theoretical analysis results. The experimental results are shown to be in good agreement with the theoretical results. The unsymmetrical covering method is effective to the laser stealth of optical system.