Patent ID: 6122079
Filing Date: 2000-09-19
Classification: G02B,G02F

Abstract:
A display diffusely illuminated by and viewable under ambient light comprising:a light-transmissive image-providing display element having a front side for viewing and a back side opposite the front side, wherein ambient light traversing the image-providing display element has in an ""open"" state a first intrinsic spectral absorptance profile, and wherein said first profile is characterized by an imbalance of absorption of different wavelengths of visible light;a reflective holographic diffuser proximate the element's back side for receiving light traversing said image-providing display element and redirecting light back through said image-providing display element, the reflective holographic diffuser including an achromatic holographic transmission diffuser and a light reflective layer; anda color compensating light filter layer incorporating coloring material in quantities sufficient to produce a second intrinsic spectral absorptance profile complementary to said first intrinsic spectral absorptance profile, and wherein the display overall has in said ""open"" state a third and predetermined spectral absorptance profile perceived by a viewer as substantially achromatic illumination, the third predetermined spectral absorptance profile being the product of said first and second profiles.