Holographic evaluation of fiber optics image transfer characteristics.

A fiber optics image-transferring element is nonisoplanatic over a surface region containing only a few fundamental resolution elements, and no meaningful or consistent evaluation of a fiber optics image can be made by examining such a nonisoplanatic region. A holographic scheme offers a solution to the problem of fiber optics image evaluation based upon examination of a nonisoplanatic region. Interfering plane waves are used to create a sinusoidal irradiance distribution that is continuous over the entire fiber optics input surface. Subsequent holographic evaluation of the photographically recorded input and output yields values of a statistical MTF by comparing the amplitude of a sinusoidal input to the average amplitude of the sinusoidal output component. The design and operation of such a holographic system is presented, and an experiment that demonstrates the advantages of the holographic measurement is discussed.