US 2013/0170250 A1 · LIGHT GUIDE PLATE AND SURFACE LIGHT SOURCE DEVICE

Abstract

A light guide plate includes an incident surface on which light outputted from point light sources is incident and an outgoing surface for outputting light incident from the incident surface. A reflection-and-propagation surface for reflecting light toward the outgoing surface is formed in a back surface opposite to the outgoing surface. The outgoing surface is made up of a propagation region adjacent to the incident surface, a propagation auxiliary region adjacent to the propagation region, a first diffusion-and-propagation region adjacent to the propagation auxiliary region, and a second diffusion-and-propagation region adjacent to the first diffusion-and-propagation region. The propagation region, the propagation auxiliary region, and the first diffusion-and-propagation region control hot spots and bright/dark lines in vicinities of the incident surface, while the second diffusion-and-propagation region controls viewing-angle characteristics of the light guide plate.

Claims12

Dependent claims

A light guide plate comprising:

an incident surface on which light outputted from a plurality of point light sources is incident;
an outgoing surface from which light incident from the incident surface is outputted;
and
a reflection-and-propagation surface at which the light incident from the incident surface is reflected so as to propagate the light toward the outgoing surface, the reflection-and-propagation surface being opposed to the outgoing surface, wherein
a plurality of prism grooves extending parallel to the incident surface are formed in the reflection-and-propagation surface,
a flat surface portion is formed in a region of the outgoing surface adjacent to the incident surface, and
a plurality of prism protrusions extending orthogonal to the incident surface are formed in a prism portion provided in a region of the outgoing surface adjacent to the flat surface portion.

4 more elements

A light guide plate comprising:

an incident surface on which light outputted from a plurality of point light sources is incident;
an outgoing surface from which light incident from the incident surface is outputted;
and
a reflection-and-propagation surface at which the light incident from the incident surface is reflected so as to propagate the light toward the outgoing surface, the reflection-and-propagation surface being opposed to the outgoing surface, wherein
a plurality of prism grooves extending parallel to the incident surface are formed in the reflection-and-propagation surface,
a flat surface portion is formed in a region of the outgoing surface adjacent to the incident surface,
in a propagation auxiliary region provided in a region of the outgoing surface adjacent to the flat surface portion, a plurality of inclined prism protrusions extending orthogonal to the incident surface and planar portions are formed alternately in a direction parallel to the incident surface, respectively,
in a first prism portion provided in a region of the outgoing surface adjacent to the propagation auxiliary region, a plurality of inclined prism protrusions extending orthogonal to the incident surface and planar portions are formed alternately in a direction parallel to the incident surface, respectively, and
in a second prism portion provided in a region of the outgoing surface not adjacent to the propagation auxiliary region but adjacent to the prism portion, a plurality of prism protrusions with a constant height extending orthogonal to the incident surface are formed while no planar portions are formed therein.

6 more elements

Dependencies are inferred from the claim text.

Light guide plate and surface light source device

Life of this patent

Light guide plate and surface light source device

Life of this patent

Abstract

Claims12