Patent ID: 9157583
Filing Date: 2015-10-13
Classification: C09K,F21V,F21Y,H05B

Abstract:
1. A lighting device comprising a light source and luminescent materials, the luminescent materials comprising a first organic luminescent material and a second organic luminescent material, wherein the light source together with the luminescent materials is configured to generate white lighting device light during operation, wherein the first organic luminescent material degrades with time at a first degradation rate, wherein the second organic luminescent material degrades with time at a second degradation rate, wherein the first degradation rate is larger than the second degradation rate, characterized in that the first organic luminescent material is configured in a first layer, that the second organic luminescent material is configured in a second layer, and that the first layer and/or the second layer is further configured to at least partly compensate for the difference in the first degradation rate and the second degradation rate in order to maintain the lighting device light substantially white during operation time of the lighting device and wherein the first layer is enclosed by an oxygen barrier.