Application of schlieren methods in recording weak variations of the intensity of coherent optical radiation in the atmosphere

The results are given of applications of knife-edge and amplitude-grating schlieren methods in an analysis of variations of the intensity of coherent optical radiation in the troposphere. An experimental analysis of the fluctuations of the angles of arrival of laser radiation under various conditions is also reported. It is shown that the sensitivity of the knife-edge method in recording weak variations is higher than the sensitivity of direct recording.