Appeal No. 2005-0825
Application 08/772,259
crystal display and the like, and more particularly, to a surface
light source device of side light type in which a light guide
plate directive in light emission is used, and a light control
element suitable for use in the device.
Representative claim 4 is reproduced as follows:
4. A surface light source device of sidelight type,
comprising:
a light guide plate having an incidence end surface, an
exiting surface and an incline surface gradually decreasing
away from the incidence end surface;
a reflecting sheet disposed along the inclined surface,
an exiting surface and an incline surface gradually
decreasing away from the incidence end surface;
a primary light source supplying illumination light to
said light guide plate from said incidence end surface, the
supplied light being deflected in the in the light guide
plate and emitted from the exiting surface of the light
guide plate; and
a light control element disposed along the exiting
surface of said light guide plate, the light control element
extending in a plane, having a light entrance side with a
prismatic surface adjacent to said light guide plate, and
having a light emitting side, spaced from the light entrance
side, said prismatic surface having repeated projections
with slopes inclined with respect to the plane of said light
control element, at least part of said slopes defining a
light diffusible surface to generate diffused light while
the light emanating from the light guide plate is radiating
within the light control element from the light entrance
side towards the light emitting side, such that a surface of
the light emitting side is illuminated in a substantially
uniform manner, reducing light effects of the reflecting
sheet.
-2-
Page: Previous 1 2 3 4 5 6 7 8 9 10 11 Next
Last modified: November 3, 2007