Apparatus for the study and recording of the infrared transmission of an object

A simple device is described that allows a good deal of information to be obtained on transmission inhomogeneities, crystal defects, and the optical quality of nontransmitting materials in the visible range. The technique uses a continuous CO2 laser which sends an infrared beam through the sample and onto a screen rendered fluorescent by ultraviolet IR radiation. Being founded on an essentially thermal process, the method is adaptable to other types of lasers. Some results garnered with the equipment are presented.