The design of laser interferometers for use in fluid mechanics

Abstract

Several workers have described interferometers for use in fluid mechanics which are designed for use with laser light. The freedom of design which is now possible leads to a multiplicity of optical arrangements, and the present paper is intended as a guide towards the choice of suitable interferometers. The paper discusses some of the general principles involved, classifies interferometer types and then shows how the use of coherent light may affect the relative merits of these types. The optical arrangements which have been suggested for each type are then reviewed, some modified designs are suggested and experimental results given. The design requirements for streak interferometry and for holography are also considered.