Aeronautical applications of holographic interferometry

The use of holography for the production of wind-tunnel interferograms of the Mach-Zehnder type is described with a discussion of the possibility of extending the process toward the interferometric study of three-dimensional flow fields. Two initial studies toward an understanding of the processes involved in three-dimensional interferometric reduction are described: (1) the hologram as a diffraction grating, and (2) intensity variation beyond both a hologram and a diffuse glass plate. Lastly, a complete prediction of a hologram of a simple, two dimensional, aperture is made. This prediction provides a tutorial device for the understanding of holography of the type used in holographic interferometry.