TRANSFER-FUNCTION FOR IMAGE-FORMATION OF OBJECTS RECONSTRUCTED FROM VOLUME HOLOGRAMS WITH DIFFERENT WAVELENGTHS

The imaging properties of coherent optical systems where images are formed as reconstructions from volume holograms are investigated. The apparent modulation transfer functions for a given optical system are determined for various imaging and reconstruction conditions, theoretically and experimentally. A model describes the formation of the image from the coherent superposition of three amplitudes. It is shown that a thin rectangular absorption grating is a suitable object for deducing the modulation transfer of the equivalent three-amplitude object from the measured intensity distribution of the grating image. These real modulation transfer functions are compared with the calculated ideal ones; this comparison represents a measure for image quality.