manufacturing a lenticular lens substrate that comprises a plurality of lenticular lenses disposed on a first surface of a translucent substrate so that each lenticular lens has a longest dimension in a lenticular lens longitudinal direction, and convex external light-absorbing sections disposed on a second surface of the translucent substrate at positions different from condensing positions in which light from the lenticular lenses is condensed; and

forming an external light-absorbing layer on slant surfaces of the external light-absorbing sections;

wherein the external light-absorbing layer is formed by roll printing;

wherein said roll printing is performed by rotating a printing roll in a forward direction and said roll printing using a feeding direction of the lenticular lens substrate being printed on that is parallel to the lenticular lens longitudinal direction on the lenticular lens substrate; and

wherein said roll printing comprises:

applying an unhardened light-absorbing material to an outer face of said printing roller, and

transferring the unhardened material to the lenticular lens substrate as said printing roller turns.