Precision Optical’s ion assisted chamber adds an extra level of coating capability to our already high level e-beam  deposition capability. During an ion-assisted deposition process, ion beams bombard the surface of the substrate, and are used to both etch and clean the surface of the substrate prior to actual deposition. In addition, ion-assist can increase the durability of the coating by converting the tensile stress that is induced between coating layers (due to differences in CTE of the materials) in to compressive stress that increases the density of the thin film layers.