Beam ratio control for holography

摘要

To form a hologram of a section of an object surface one end of each of a pair of elongated, flexible, optical fibers is illuminated with a laser beam through an optical mechanism which allows adjustment of the amount of light that falls on each of the fiber ends. The opposite end of one of the fibers is disposed adjacent to the object of which the hologram is to be formed so that the light output of that fiber diffuses and illuminates the relevant surface. A photographic plate is disposed to receive light reflected from the object surface as well as a reference beam radiating from the output end of the other fiber. A photodetector device receives a portion of the reference beam at one input and a portion of the object beam at another input and provides a visual indication of the relative intensity of the beams. The input to the fiber elements is adjusted to achieve the desired beam ratio for forming a hologram.