| 摘要 |
PROBLEM TO BE SOLVED: To provide a large-sized projection lens, which has high shape precision in spite of its being light-weight and low price and can project an image of high precision, having no distortion and no deformation by being incorporated into a projection device for projecting to a screen in particular, not in the vertical direction but in an inclined direction, especially from below in the inclined direction, and to provide a substrate thereof and a composition for the substrate. SOLUTION: In a resin composition for constituting the projection lens by providing a reflection layer on the surface of an optical function forming plane of an aspherical molding having >=150 cm2 plane area, with >=10 cm minimum width for the plane, >=3 mm molding thickness, the composition for the substrate of the aspherical lens is constituted by containing an amorphous thermoplastic resin, in which OH group content is <=250 ppm and glass transition point is >=70 deg.C, and a mold releasing agent consisting of a fatty acid ester of an alcohol by 100 to 2,000 ppm with respect to the resin.
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