ASA 125th Meeting Ottawa 1993 May

4pMU12. Increasing the depth of field in holographic interferometry.

Dell O. Fystrom

Phys. Dept., Univ. of Wisconsin, LaCrosse, WI 54601

Thomas D. Rossing

Northern Illinois Univ., DeKalb, IL 60115

Holographic interferometry is widely used to determine the modes of vibration in a wide variety of objects, such as musical instruments. Use of two or more object beams is a convenient and inexpensive way to increase the depth of field (or coherence volume) in holographic interferometry. This technique was used, for example, to make time-average holograms of the inside and outside surfaces of a vibrating drum shell simultaneously.