Abstract
Thin layers of many halides and chalcogenides can be used for image recording since they decompose when illuminated, at a suitable temperature, with light that is absorbed in their fundamental absorption region. A review is given of this process and of the range of materials now available for ‘halide layer photography’. Potential applications of halide layers in image recording, holography and information storage are discussed in the light of recent experiments on the sensitivity, resolution, contrast and stability of the layers.