Dai Nippon Printing Co., Ltd.

Yuko Mori

Katsunori Shintani

Makoto Honda

Katsunori Takahashi

Hideki Miyata

Toshie Chijiwa

A lens sheet capable of preventing reflection of extraneous light without decreasing extraneous light absorption, having extraneous light absorbers that can be readily formed by printing and are scarcely stained. The present invention also provides a rear projection screen including such a lens sheet. A rear projection screen has a Fresnel lens sheet and a lenticular lens sheet placed on the viewing side of the Fresnel lens sheet. The lenticular lens sheet has lenses formed on those portions of the light-emergent-side surface of the sheet-shaped substrate part through which light converged by other lenses pass, and extraneous light absorbers formed on those portions of the light-emergent-side surface of the sheet-shaped substrate part through which light converged by the other lenses does not pass. Each extraneous light absorber includes a black-colored binder resin and a number of light-diffusing particles subjected to coloring treatment, incorporated in the binder resin.

Lens sheet and rear projection screen including the same

A lenticular lens sheetcomprises a plurality of lens elements of incidencearranged on the incidence side, and a plurality of lens elements of emergencearranged on the emergence side. The light that has passed through each lens element of incidenceconverges via the protruding apex of the corresponding lens element of emergence. The lens plane of the center portion C of each lens element of emergence, the width of this portion C being a half of the total lens width L (i.e., L/2), is in the shape defined by a curved line fulfilling the conditions expressed by the following numerical formulae (1) to (4), and the lens plane of each side portion S of each lens element of emergence, the width of this portion S being a quarter of the total lens width L (i.e., L/4), is in the shape defined by a curved line fulfilling the conditions expressed by the following numerical formulae (5) to (8): y=a&#xd7;b&#x2212;e (&#x2212;L/4&#x2266;x&#x2266;0) . . . (1), y=a&#xd7;b&#x2212;e (0&#x2266;x&#x2266;L/4) . . . (2), 3.0&#xd7;10&#x3c;a&#x3c;3.8&#xd7;10. . . (3), 1.0&#xd7;10&#x3c;b&#x3c;1.0&#xd7;10. . . (4), y=c&#xd7;d&#x2212;e (&#x2212;L/2&#x2266;x&#x2266;&#x2212;L/4) . . . (5), y=c&#xd7;d&#x2212;e (L/4&#x2266;x&#x2266;L/2) . . . (6), 3.0&#xd7;10&#x3c;c&#x3c;3.1&#xd7;10. . . (7), and 2.7&#xd7;10&#x3c;d&#x3c;4.0&#xd7;10. . . (8).

Growing community of inventors

Shinjuku-ku, Japan

Yuko Mori