Low-E glass is Low emissivity coated glass which adopts vacuum magnetic control sputtering technology to coat the glass with layers of silver or tin or other metal compounds. The liquid metals or metal powder were directly sprayed onto thermal glass and adhered to its surface at the stage of glass cooling. It is classified into online and Offline Low-E according to its processing technique, the former with single variety and is a hard coating which can be guaranteed for 30years, the latter versatile in color and transmittance, is soft coating but weak in adhesion and can’t be preserved in bareness.