Method of Characterizing Hologram-Recording Materials*

Abstract

A new method of characterizing hologram-recording materials is presented. This method is applicable to all types of holograms. An ideal hologram-recording material permits the reconstruction of a wave front linearly proportional to the original subject wave front. Based on this concept of linear reconstruction, a material can be characterized by the properties of holograms recorded in the material with two interfering plane waves. If η is the hologram diffraction efficiency, E0 the average exposure, and V the visibility of the interference fringes, the ideal material is shown to be characterized by the relation √η = SE0V, where S is a constant. For the ideal material, curves of √η vs E0 with constant V as parameter and curves of √η vs V with constant E0 as parameter are families of straight lines. Since η, E0, and V are measurable quantities, similar curves can also be plotted for any real material. However, for a real material these curves are straight lines only within limited ranges of η, E0, and V. Within these ranges, the material may be considered ideal. Besides indicating the linearity, a set of √η−E0 or √η−V curves for a particular material also indicates explicitly the maximum hologram diffraction efficiency, the optimum average exposure value, and the holographic sensitivity of the material. √η−V characteristics of some common hologram-recording materials are shown, and the properties of the holograms recorded in these materials are compared.