The holo-diagram: a practical device for making and evaluating holograms.

The engineer is interested in the measurement of small deformations of large machine parts, for instance the deformation caused by force and temperature of large slideways in machine tools. For this purpose it was thought that hologram interferometry would be particularly suitable. However, no general method appeared to be available either for the making or for the evaluation of holograms recording large objects; therefore, the method described in this paper was worked out. It is based on the use of a special diagram which the author has named the holo-diagram. This can be used to make both ordinary holograms and Lippman holograms. We have found that it simplifies the evaluation of interference holograms for measuring dimension, deformation, interferometers. and vibration. This work also inspired new ideas on the design of interferometers.