A method of selection of an illuminator for use in an accelerated light stability test device chamber is described that employs measuring and comparing the spectral irradiance of at least one light source for use in an illuminated device and at least one illuminator suitable for use in an accelerated weathering chamber and selecting an illuminator having certain irradiance criteria. Also described are methods of accelerated light stability testing of an illuminated display components and an accelerated light stability tcst device.