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
In order to study the atmospheric turbulence's influence on active laser reconnaissance, a theoretical model of cat-eye
system illuminated by Gaussian-beam which propagates through atmospheric turbulence over a long distance was
constructed. The mean irradiance and the scintillation index were calculated under the Rytov approximation. The
theoretical analysis and numerical simulation results indicate that the mean irradiance and scintillation index of the
active laser reconnaissance echo influenced by atmospheric turbulence are both increased near the optical axis.
Experiment was carried out to validate the theoretical analysis results and the experimental results are shown to be in
good agreement with the theoretical predictions.