Patent ID: 7345750

Claim:
A method of accelerated light stability testing comprising exposing at least one component of an illuminated display having a light source in an accelerated light stability test device wherein the test device has an illuminator selected by a) measuring the spectral irradiance for at least wavelengths ranging from 250 nm to 500 nm i) of at least one light source for use in an illuminated display as would be emitted during use of the light source in the illuminated display, and ii) at least one illuminator suitable for use in an accelerated weathering chamber; b) comparing the spectral irradiance measurements of the illuminator to the light source; c) selecting an illuminator wherein i) a first ratio of irradiance for wavelengths below 300 nm to the irradiance at wavelengths from 300 nm to 500 nm of the illuminator ranges from about 0.2 times to 2.6 times greater than the light source or the first ratio is greater than 2.6 and a filter is disposed proximate the illuminator to reduce the first ratio; ii) a second ratio of irradiance for wavelengths from 300 nm to 400 nm to the irradiance at wavelengths greater than 400 nm to 500 nm of the illuminator ranges from 0.9 times to about 15 times greater than the light source; iii) for wavelengths greater than 300 nm the illuminator has an irradiance greater than the light source, or has 50% to 100% of the irradiance of the light source and temperatures above 50° C. are employed during the accelerated light stability test.