Abstract: A backlight module includes a light guide plate and at least one light source. The light guide plate has a first light-emitting surface, a second light-emitting surface opposite the first light-emitting surface, and at least one side surface connected between the first light-emitting surface and the second light-emitting surface. The light guide plate has a first substance and a second substance surrounding the first substance, and the second substance is different to the first substance to form at least a first light reflecting/diffusing interface and a second light reflecting/diffusing interface. A light beam emitted by the light source is deflected by the first light reflecting/diffusing interface and output via the first light-emitting surface, and a light beam emitted by the light source is deflected by the second light reflecting/diffusing interface and output via the second light-emitting surface.

Abstract: A light guide unit including a light guide plate and a scattering reflective unit is provided. The light guide plate has a first surface, a second surface opposite to the first surface, and a light incident surface connecting the first surface and the second surface. The light incident surface includes a first recess and a second recess arranged in a sequence from the first surface to the second surface. An average radius of curvature of the first recess is less than an average radius of curvature of the second recess. The scattering reflective unit is disposed on the second surface. A light source module is also provided.

Abstract: A light guide unit including a light guide plate and a scattering reflective unit is provided. The light guide plate has a first surface, a second surface opposite to the first surface, and a light incident surface connecting the first surface and the second surface. The light incident surface includes a first recess and a second recess arranged in a sequence from the first surface to the second surface. An average radius of curvature of the first recess is less than an average radius of curvature of the second recess. The scattering reflective unit is disposed on the second surface. A light source module is also provided.

Abstract: A backlight module includes a light guide plate and at least one light source. The light guide plate has a first light-emitting surface, a second light-emitting surface opposite the first light-emitting surface, and at least one side surface connected between the first light-emitting surface and the second light-emitting surface. The light guide plate has a first substance and a second substance surrounding the first substance, and the second substance is different to the first substance to form at least a first light reflecting/diffusing interface and a second light reflecting/diffusing interface. A light beam emitted by the light source is deflected by the first light reflecting/diffusing interface and output via the first light-emitting surface, and a light beam emitted by the light source is deflected by the second light reflecting/diffusing interface and output via the second light-emitting surface.

Abstract: An illuminated sign having front, back and side surfaces. A plurality of first cavities are formed into the back surface of the sign. A plurality of light emitting modules are disposed in the plurality of first cavities. The modules each include a light emitting diode having an emission axis and for producing at least some light output generally parallel to the emission axis, an optical device disposed adjacent the light source having a reflective surface for reflecting the light output in directions that are generally perpendicular to the emission axis, and a guide element disposed adjacent the optical device for coupling the reflected light output into the interior of the sign. The guide element includes a second cavity formed therein in which the optical device is disposed. The front surface is illuminated by the coupled light output from the light emitting modules by reflection and/or diffusion inside the sign.