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When the aircraft flights in the earth's atmosphere with high speed, it will bring the aero-optical
effects into optical imaging detector system. These aero-optical propagation effects are caused by two parts: high-speed
turbulent flow field and aero-thermal window. This paper discusses the light propagation effects caused by high-speed
turbulent flow field. The high-speed turbulent flow field is a highly non-uniformly time-varying medium, which
possesses some characteristics depending on both time and space. While the light propagates through such a medium, the
imaging on target of detector system will be affected. This paper describes both the temporal and spatial characteristics
of high-speed turbulent flow field. To obtain the instantaneous distribution characteristics of turbulent flow field, one
method is applying NPLS-based measurement technique of supersonic flow field. The three-dimensional density field is
obtained by the relationship between density and image gray. We studied the physical phenomena of optical wave
propagating through turbulent flow field and then the caused optical distortion. The NPLS technique is a high-resolution
measurement method of the fine structure of supersonic three-dimensional complex flow field. The time resolution of
NPLS technique is 6 ns, and the time correlation resolution is 200 ns. These resolutions can satisfy the description of the
characteristics related to the time scale. We are able to describe the time correlation characteristics of density field using
NPLS image with different time intervals. Finally, the optical transmission effects of light, which propagates through
turbulent flow field, were simulated and studied. According to the instantaneous density field obtained from the NPLS
technique, it is carried out that the simulation of optical transmission effect of high-speed turbulent flow field at several
typical states. Then, using the ray-tracing method, the optical distance OPDi along the propagation path is obtained.
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