Low emissivity coated glass is also called Low-E glass. Low-E glass is a kind of glass whose surface is coated with low emissivity coating silver and metal-oxide film so that the glass takes on different colours. Its main functions are to reduce the U value of glass, selectively reduce Sc and comprehensively improve energy saving property of glass.

Its main features: high infrared reflectivity, ability to directly reflect far infrared thermal radiation, low surface emissivity, weak ability to absorb external energy, hence little-reradiated heat energy; a wide range of shading coefficient Sc, and ability to control sunlight transmittance according to needs to cater to requirements of different areas. It can be divided into high transmission low-E glass and sun shading low-E glass.