ABSTRACT
In many forms of laser technology the coherent light from the laser forms a spot that can be a concentrated source of heat or, in laser surface treatment, for example, a rather more diffuse region of heating. Some of the techniques used in the simpler mathematical models that first found use in welding problems in fact prove to be of considerable value in more general contexts. In particular, the point and line source solutions associated in the context of welding with the name of Rosenthal,1 but also very well described from a rather different point of view by Carslaw and Jaeger,2 have proved to be extremely useful. They will be derived first before considering specific applications, after which they will be used to obtain simple descriptions of the temperature in a workpiece. More elaborate models can be developed later.
