| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical sheet in which deformation such as deflection is reduced even being enlarged, and luminance unevenness caused by such deformation can be reduced, and which has high condensing properties, to provide a surface light source device provided therewith, and to provide a transmissive display device. <P>SOLUTION: The lens sheet 14 includes: a plurality of unit lenses 145 arranged at the face of an emission side; and a reflecting layer 142 with openings 143 formed at the positions corresponding to the unit lenses 145. In the thickness direction of the lens sheet 14, the reflecting layer 142 is formed on the side of the unit lenses 145 rather than a condensing point f, when parallel light is made incident from the side of the unit lenses 145, on which the parallel light condenses, and provided that the point v to form into the bottom of the ravine between the unit lenses 145 in the thickness direction and a face 141a to form into the most incidence side in the lens sheet 14 is defined as T; the dimensions in the screen vertical direction of the lens sheet 14 is defined as L; the density on the region to form the incident side rather than the point v is defined as C; and a Young's modulus is defined as E, the relation of T>((C×L<SP>3</SP>)/(16×E))<SP>1/2</SP>is satisfied. <P>COPYRIGHT: (C)2011,JPO&INPIT |
