An Innovative Approach to High Speed Measurement of an Aero-Optically Distorted Wavefront

Aerodynamic flow about flight vehichles with an onboard optical sensor often contributes to image degradation of the optical signal received by the sensor. This phenomenon is called aero-optic degradation, and is caused by the wavefront distortion optical radiation suffers upon transmission through the aerodynamic environment. This aero-optic degradation occurs on a continuous spatial and temporal basis, and can be quite severe, especially when the aerodynamic environment is highly turbulent. Progress in the design of reliable flight optical sensors requires an ability to accurately determine the impact aerodynamic flow environments have on propagating optical radiation. This proposal presents an innovative instrument to directly measure the aero-optically distorted wavefront at high speed and high resolution, the aerodynamic environment. The device consists of a specially designed Hartmann Waveront Sensor (HWS) adapted ot a high speed camera, which will provide phase maps of the time varying aero-optic distortions imposed on optical waves at the high temporal frequencies and small spatial resolutions required ot meet the need for an optical diagnostic tool for aerodynamic turbulence research. The adaptation of an ingenious high speed adaptive optical element provides a new opportunity to perform "real-time" correction to the distorted waves measured by our HWS sensor. Miniaturization of this diagnostic tool could provide the solution to optical sensing onboard flight vehicles.