Analysis of Optical Wavefront Distortions Caused by the Atmosphere

摘要

In order to obtain the optimum design of a wavefront shearing interferometer to measure optical wavefront distortions caused by the atmosphere, some preliminary experiments using a pointing interferometer have been considered. Use of a pointing interferometer would enable the shape of wavefront along the line of flight to be determined. A pointing interferometer, which at a later date could be modified very simply to measure wavefront distortion, had been constructed and preliminary measurements indicate that the technique could be used to measure changes in orientation of the wavefront of less than one arc second. The construction of a pointing interferometer for use in flight tests appears to be feasible. Interferograms of wavefront distortion, caused by artificially produced local air turbulence, indicate that distortion is absent over some short time intervals. Hence there would be no image degradation due to the turbulence, if the film were exposed during one of these intervals. The wavefront distortion is also shown to be much greater when the region of turbulence is in the vicinity of the interferometer as compared to near the source.