Patent ID: 8686449
Filing Date: 2014-04-01
Classification: F21K,F21V,F21Y,G02B,H01L

Abstract:
1. A light emitting device comprising: a substantially planar light transmissive substrate having a light emitting surface and an opposite surface and wherein the substrate is configured as a light guiding medium; at least one phosphor material disposed as a layer adjacent to the light emitting surface with a plurality of window areas; and at least one source of excitation radiation of a first wavelength positioned adjacent to at least one peripheral edge of the substrate, wherein the source is configured to couple excitation radiation into the substrate such that it is waveguided within the substrate by total internal reflection; wherein the light emitted by the device from the light emitting surface comprises first wavelength radiation and second, longer wavelength photoluminescent light emitted by the phosphor layer as a result of excitation by the source, and wherein light of the first wavelength and light of the second wavelength are emitted through the plurality of window areas.