| 摘要 |
PROBLEM TO BE SOLVED: To provide a front plate and a transmissive screen which do not cause the loss of a light quantity, is easily manufactured, and has the improved uniformity of the luminance of a screen whichever position it is observed from. SOLUTION: The front plate is equipped with a lens layer 31 where a plurality of unit lenses to emit a part of an incident light beam from an emitting part after totally reflecting it by total reflection parts (31a and 31b) are arranged side by side so that their longitudinal directions are nearly horizontal, and an external light absorption layer 32 which is provided at least on the total reflection parts (31a and 31b) and absorbs and/or attenuates external light from an emitting side. At least at the lower part than the center of the front plate 30, angles (β1 toβ4) formed by the main optical path of the incident light beam and the downside total reflection surfaces 31b of the unit lenses are made larger than angles (α1 toα4) formed by the main optical axis and the upside total reflection surfaces 31a of the unit lenses. COPYRIGHT: (C)2005,JPO&NCIPI
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