Reversible window unit for alternately reflecting and absorbing solar energy
US4235048A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 3, 1978 |
| Grant date | Nov 25, 1980 |
| Priority date | — |
| Expiry date | Jan 3, 1998 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S126/908
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A multiple layer coating is disclosed which enables a window unit to function efficiently as a solar energy collector in winter and as a heat shield in summer. The coating comprises a layer of metal which provides high reflectance of incident solar energy from one side of a coated transparent substrate and a layer which provides high absorption of incident solar energy by the other side of the coated substrate. The absorbing layer may be a single film of a highly absorptive material, but is preferably a dual film of an absorptive material covered by an antireflective material. The absorptive layer may also comprise multiple alternating films of metal and dielectric materials which effectively absorb incident solar energy. The reflective and absorptive layers are selected to provide the coated article with a low U-value to prevent heat radiation from the warm building to the cold environment in winter and from the hot environment to the cooled building in summer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.