Abstract

Optical computer assisted tomographic (OCAT) reconstruction of a three-dimensional unsteady object requires simultaneous acquisition of many line-of-sight measurements (projections). A projection represents a measurement of absorption or index-of-refraction along the pathlength. To acquire one projection a source, often a laser, is used in conjunction with beam steering and recording elements; all necessary projections can be obtained by either rotating the object, by rotating the data acquisition apparatus or alternatively by replicating the system required for making one projection. All these approaches have been investigated in the past for the purpose of making, for instance, measurements of quasi-stationary objects (Ref ¹) or time-averaged measurements of complicated turbulent flows (Ref ²). Replication often leads to cumbersome and expensive optical systems and the lack of availability of a simple fast data acquisition system has impeded wide spread use of optical tomography in fluid mechanics research.

© 1984 Optical Society of America