Abstract

Holographic interferometry is used in wind tunnel testing to obtain quantitative results of the density distribution in the flow field. Holographic interferograms were produced by a pulsed-ruby holographic interferometer in a supersonic tunnel at nominal free-stream Mach number 2 (Fig. 1). To improve the resolution of the interferogram, homorphic filtering for image enhancement was performed with a digital image-processing system (Fig. 2). In comparison with the original image, the black/white brightness difference of the image was reduced noticeably, and some details of the interference pattern can be recognized.

© 1985 Optical Society of America