Planar lighting device

Abstract

A planar lighting device according to an embodiment includes a light guide plate and a reflecting member. The light guide plate has an incident surface that receives light output from a light source and an output surface that outputs the light received by the incident surface. The reflecting member faces an end surface opposite to the incident surface of the light guide plate and reflects light leaking from the end surface. A plurality of first prisms are formed on an opposite surface opposite to the output surface-of the light guide plate to be away from the output surface stepwise from the incident surface to the end surface. The first prisms cause the light reflected by the reflecting member and traveling from the end surface toward the incident surface to be output from the output surface in a first direction as first light and cause the light entering into the incident surface and traveling from the incident surface toward the end surface to be output from the output surface in a second direction different from the first direction as second light.

Dependencies are inferred from the claim text.