Characteristic curve and hologram recording conditions

It is proposed that the dependences of the refractive index n and of the absorption coefficient κ on the recording conditions be used as the main characteristics of a holographic medium. An analysis is made of the recording of holograms in media whose refractive index n and absorption coefficient κ vary under the influence of light and this variation is described by a function analogous to the characteristic curve of photographic materials. Experimental results obtained in the recording of holograms in As₂S₃. films are reported.