LIGHTING DEVICE WITH OFF-STATE WHITE APPEARANCE

摘要

A lighting device (400) with an off-state white appearance is provided. The lighting device comprises a light source (403), having a white appearance in an on-state and a colored appearance in an off-state, and a switchable optical element (404) downstream from the light source. The colored appearance of the light source is caused by a photoluminescent material in the light source. The switchable optical element has at least a transmissive state and a state being reflective in the wavelength region in which the light source absorbs light, resulting in a white appearance when the light source is in its off-state and the switchable optical element is in its reflective state. According to an embodiment of the invention, the lighting device (400) is arranged as a luminaire further comprising an optical cavity (401) and a window (402) covering the optical cavity. The light source (403) is arranged inside the optical cavity and the window is provided with the switchable optical element (404).