To obtain a new light-accumulating material by dispersing light-accumulating ceramic powder in a silica gel with carbon introduced into its skeleton so as to emit fluorescence, and to obtain a light source which is human-friendly, conserves energy and is useful for disaster prevention by improving properties of an illumination lamp such as an LED as a point light source to properties as a surface light source.

Light-accumulating resin pellets containing a fluorescing light-accumulating silica gel obtained by dispersing light-accumulating ceramic powder in a silica gel with carbon introduced into its skeleton are arranged on the back side of a light guide plate of an edge light comprising a plurality of LEDs, so that light emitted from the LEDs is made incident on the light-accumulating resin pellets and that light emitted by the LEDs is diffusely reflected from the pellet surface. Since the lighting-up time of the LEDs can be shortened by the afterglow effect of the light-accumulating material, energy is conserved.