Abstract: A planar illumination device according to an embodiment includes a light guide plate, an attenuation element, and a plurality of light sources. The light guide plate has a light-emitting surface that is a main surface through which light is emitted and a light-receiving side surface that is a side surface intersecting with the light-emitting surface and receives the light. The attenuation element attenuates the light entering through the light-receiving side surface. The light sources face the light-receiving side surface of the light guide plate and are arranged in parallel with one another at certain intervals. One of the intervals closer to the attenuation element is smaller than another of the intervals distanced from the attenuation element.

Abstract: A planar illumination device according to an embodiment includes a light guide plate, an attenuation element, and a plurality of light sources. The light guide plate has a light-emitting surface that is a main surface through which light is emitted and a light-receiving side surface that is a side surface intersecting with the light-emitting surface and receives the light. The attenuation element attenuates the light entering through the light-receiving side surface. The light sources face the light-receiving side surface of the light guide plate and are arranged in parallel with one another at certain intervals. One of the intervals closer to the attenuation element is smaller than another of the intervals distanced from the attenuation element.

Abstract: A planar illumination apparatus according to an embodiment includes a light source and a light guide plate. The light source includes a light emitting diode and a wavelength conversion material that is excited by light emitted from the light emitting diode so as to emit light, and emits white light. The light guide plate includes an incident end surface on which the light source is disposed, and an emission surface that emits light incident from the incident end surface. The light guide plate is provided with a light scattering unit on at least one of the emission surface and a rear surface opposed to the emission surface. The light scattering unit mainly scatters light emitted from the light emitting diode than light emitted from the wavelength conversion material.

Abstract: A planar illumination apparatus according to an embodiment includes a light source and a light guide plate. The light source includes a light emitting diode and a wavelength conversion material that is excited by light emitted from the light emitting diode so as to emit light, and emits white light. The light guide plate includes an incident end surface on which the light source is disposed, and an emission surface that emits light incident from the incident end surface. The light guide plate is provided with a light scattering unit on at least one of the emission surface and a rear surface opposed to the emission surface. The light scattering unit mainly scatters light emitted from the light emitting diode than light emitted from the wavelength conversion material.

Abstract: A spread illuminating apparatus includes a light source that emits white light, and a light guide plate including an incident light surface which is an end surface at which the light source is disposed and an emitting part that emits light which has entered from the incident light surface in a spread pattern from an emitting surface. The light guide plate includes an incident light wedge part between the incident light surface and the emitting part, the incident light wedge part including an inclined surface and tapering in thickness from the incident light surface side toward a forward direction. Also, a blue light diffusing part that scatters mainly blue light by Rayleigh scattering is provided on at least one of the emitting surface side or an opposite surface side of the emitting surface side near the incident light wedge part.