Patent ID: 8641252

Claim:
A planar light-emitting device comprising: a light source element configured to emit light; a light guide plate having a housing hole that houses the light source element, an upper face defining a light-emitting face that is configured to emit the light from the light source element, and a side end face arranged relative to the upper face, the side end face having an inclined portion that is located next to the housing hole in a first direction of the light guide plate and a flat portion that is located next to the inclined portion in a second direction that is perpendicular to the first direction, the inclined portion having an inclination angle with respect to the flat portion such that the light reflected at the inclined portion is prevented from returning the housing hole; and a reflective film disposed on the inclined portion and the flat portion of the side end face of the light guide plate, an interface between the side end face and the reflective film defining a light reflecting face that is configured to reflect the light from the light source element.