Pulsed laser ablation, where a surface is eroded using a laser, is a key part of manufacturing processes in aerospace, automobiles and medicine. In each of these instances the measurement of the outcomes of the ablation process, such as the quality of the eroded surface, is important. There are many ways of studying and measuring metallurgical, geometrical and quality characteristics during the process in real time or near real time.

For laser ablated surfaces, chief among the factors that need to be measured are spatter formation and crater depth. Spatter is produced when the melted material and ejected particles are scattered vertically and laterally and end up covering the periphery of the laser ablated hole. In most of studies, a CCD camera has been applied to study those characteristics in process. As the formation of an ablated depth is essentially a random process, measuring depth has some uncertainty and because of this, finding a reliable, repeatable and real-time method to evaluate the ablation depth has been difficult.

During the pulsed laser ablation of metals, as well as other materials, the development of a plasma plume close to the ablated surface leads to the emission of radio frequency energy. This DCU research collaboration describes a process for analysing the received radio frequency power.