Limitation of the lidar angular resolution caused by the atmospheric turbulence and the lidar telescope aberrations

Abstract

The image quality of the laser sounding of distant objects is limited mainly by the resolution of the optical system 'a telescopic objective -- a turbulent layer.' Fried formulated a theoretical expression concerning the system's resolution, but he assumed a diffraction-limited objective. Our goal here is to increase the estimation accuracy of the resolution of lidar optical systems, using the measured in advance resolution of the receiving objective. We show the possibility to substitute the maximum angular frequency of a diffraction- limited objective, in the expression of the optical transfer function, by the measured angular frequency of the actual objective. We propose a method, based on measuring the common resolution of the system 'a lidar telescope -- a turbulent layer,' for estimating the structural constant Cn2 of the turbulence. We have also calculated numerically the resolution of such a system for one-kilometer turbulent layer.