OPTICAL ELEMENT AND DISPLAY DEVICE

摘要

Disclosed is an optical element having high light extraction efficiency from the side face of a light guide, and also disclosed is a display device. The optical element comprises: a rod-shaped light-guide (11) having either a polygonal or a circular cross section; a light incident portion (15) formed on a circumferential edge portion of one end face (11a) of the light guide (11), and having an inclined face wherein a normal vector (13) thereto includes a circumferential direction component (13a) of the one end face (11a) such that incident light (12) advances toward the other end face (11b) in a helical pattern in a process of repeated total reflection from the side face without passing through the cross-sectional center of the light guide (11); and a light-emitting portion (16) formed on the side face of the light guide (11) to guide light within the light guide (11) to outside the light guide (11).