1. M. F. Weber, “Backlighting system using a retroreflecting polarizer,” US Patent No, 5,422,756, issued June 6, 1995;
2. D. J. Broer, J. A. M. M. v. Haaren, G. N. Mol, and F. Leenhouts, “Reflective cholesteric polarizer improving the light yield of back-and side-Lighted flat panel liquid crystal displays”, SID'95 Asia Display Digest, 735(1995);