Recent advances in aero-optics

The passage of a planar-wavefront optical beam through a turbulent, index-o f-refraction-variant flowfield imprints dynamically changing aberrations on the wavefront; these aberrations have detrimental effects on the performan ce of optical systems making use of the beam. The study of these aberration s (when the aberrating flowfield is of relatively short propagation length in the near field of the optical system) is referred to as aero-optics. Thi s article begins with a brief discussion of the traditional approach to qua ntifying aero-optic interactions. It then reviews how the development of hi gh-speed wavefront sensors over the past 10 years has impacted the fluid-dy namics and optics fields. In particular, the fluid-dynamic mechanisms creat ing optical distortions are now better understood, and successful aero-opti c scaling laws have been developed. The article concludes with a descriptio n of future trends in aero-optical research. (C) 2001 Elsevier Science Ltd. All rights reserved.