A lens unit comprising: two lens plates (130a, 130b) each of which has a first lens row including a plurality of lenses aligned in a first direction at a predetermined interval and a second lens row including a plurality of lenses aligned at the predetermined interval in the first direction, wherein optical axes of the lenses of the one lens plate being respectively aligned with optical axes of the lenses of the other lens plate [p. 7, l. 20-23 and 29-33]; and a light blocking member disposed between the two lens plates and including a plurality of openings that extend therethrough such that each of the lenses of the first and second lens rows has an optical axis passing through a corresponding one of the openings, the openings being arranged in two rows each of which has a plurality of openings aligned in the first direction at the predetermined interval [p. 10, l. 14-21], characterized in that: the corresponding one of the openings has two perimeter portions (141a, 141b), each of the two perimeter portions being spaced apart by a first distance from the optical axis of said each of the lenses, the two straight perimeter portions extending in a second direction perpendicular to the first direction [claim 6; p. 11, l. 8-15]; the corresponding one of the openings further has a circumferential perimeter portion that is spaced apart by a second distance from the optical axis of said each of the lenses in the second direction, the second distance being longer than the first distance; and each of the lenses includes a lens surface that includes first straight perimeter portions extending in the second direction substantially perpendicular to the first direction such that two adjacent lenses belonging to the same lens row are contiguous with each other at the first perimeter portions. [p. 8, l. 2-7] two lens plates (130a, 130b) each of which has a first lens row including a plurality of lenses aligned in a first direction at a predetermined interval and a second lens row including a plurality of lenses aligned at the predetermined interval in the first direction, wherein optical axes of the lenses of the one lens plate being respectively aligned with optical axes of the lenses of the other lens plate [p. 7, l. 20-23 and 29-33]; and a light blocking member disposed between the two lens plates and including a plurality of openings that extend therethrough such that each of the lenses of the first and second lens rows has an optical axis passing through a corresponding one of the openings, the openings being arranged in two rows each of which has a plurality of openings aligned in the first direction at the predetermined interval [p. 10, l. 14-21], characterized in that: the corresponding one of the openings has two perimeter portions (141a, 141b), each of the two perimeter portions being spaced apart by a first distance from the optical axis of said each of the lenses, the two straight perimeter portions extending in a second direction perpendicular to the first direction [claim 6; p. 11, l. 8-15]; the corresponding one of the openings further has a circumferential perimeter portion that is spaced apart by a second distance from the optical axis of said each of the lenses in the second direction, the second distance being longer than the first distance; and each of the lenses includes a lens surface that includes first straight perimeter portions extending in the second direction substantially perpendicular to the first direction such that two adjacent lenses belonging to the same lens row are contiguous with each other at the first perimeter portions. [p. 8, l. 2-7] the corresponding one of the openings has two perimeter portions (141a, 141b), each of the two perimeter portions being spaced apart by a first distance from the optical axis of said each of the lenses, the two straight perimeter portions extending in a second direction perpendicular to the first direction [claim 6; p. 11, l. 8-15]; the corresponding one of the openings further has a circumferential perimeter portion that is spaced apart by a second distance from the optical axis of said each of the lenses in the second direction, the second distance being longer than the first distance; and each of the lenses includes a lens surface that includes first straight perimeter portions extending in the second direction substantially perpendicular to the first direction such that two adjacent lenses belonging to the same lens row are contiguous with each other at the first perimeter portions. [p. 8, l. 2-7]