Lamp with IR reflecting film and light-scattering coating
AssigneeGeneral Electric Company
InventorsPamela K. Whitman, Thomas G. Parham, Thomas M. Sharda
Life of this patent
Estimating the term…
Abstract
Incandescent lamps or arc lamps having an infrared red reflecting multilayer optical interference filter on the outer surface of the vitreous or fused quartz lamp envelope enclosing the filament have a light-scattering coating applied over the filter to scatter light emitted by the lamp and thereby diffuse the filament image. The light-scattering coating consists of light-scattering particles, such as alumina, dispersed in a silica matrix. This coating is formed by applying to the filter a silicone solution in which is dispersed colloidal silica and light-scattering particles and pyrolyzing at high temperature to drive off the organic components and form the silica matrix.
Claims18
A light-transmissive article having at least one surface with at least a portion of said surface having a multilayer optical interference filter with a light-scattering coating comprising light-scattering particles in a vitreous substantially pure, silica binder disposed adjacent said filter.
A lamp comprising a light-transmissive envelope enclosing a source of IR and visible light radiation with a multilayer optical interference filter disposed adjacent said envelope which transmits visible light and a light-scattering coating comprising light-scattering particles in a vitreous substantially pure, silica binder disposed adjacent said filter.
A lamp comprising a light-transmissive, vitreous envelope enclosing a source of IR and visible light radiation with a multilayer optical interference filter disposed adjacent said envelope which transmits visible light and with a light-scattering coating comprising light-scattering particles in a vitreous substantially pure, silica binder disposed adjacent said filter, wherein said coating is formed by dispersing particles of light-scattering material in a dispersion of colloidal silica in a liquid silicone solution which is disposed adjacent said filter and heated at elevated temperature to drive out the organic component of said silicone and convert said silicone and said colloidal silica to a vitreous, silica binder.
Dependencies are inferred from the claim text.