Layer structure usually applied onto the glass surface by a CVD or PVD process to influence the spectral properties of the component such as transmission and reflection. Such coating is essential for energy conserving glazing where IR radiation may be controlled by this layer. There are several coating classes which are distinguished as follows:

• Hard Coated (HC): This describes a type of coating or covering a glass surface in a way that the resulting surface is rather resistant against damage, at least at a similar level as compared to standard Floatglass. In a composite, the surface may be exposed to the environment.
• Soft Coated (SC): This describes a type of coating covering a glass surface resulting in a surface that is more vulnerable by environmental conditions such as moist, dirt etc. Soft coated glass panes require more care in processing.
• Coated with foil protection (FC): This describes glass panes where the coating (typically a soft coating) is protected against environmental influence by a foil that might have to be removed when the glass is to be processed.