Light guide plate, backlight unit having the same, display apparatus having the same, and method of manufacturing the same

A backlight unit comprising:

• a light source configured to emit a light;
• and
• a light guide plate comprising a light incident surface to which the light is configured to be incident, a light exit surface from which the light incident through the light incident surface is configured to exit, a bottom surface facing the light exit surface configured to reflect at least a portion of the incident light, and a scattering pattern disposed on the bottom surface,
• wherein the scattering pattern comprises:
• a first protrusion portion protruding from the bottom surface;
• a recess portion disposed along a circumference of the first protrusion portion and recessed from the bottom surface;
• and
• a second protrusion portion spaced apart from the first protrusion portion and disposed along a portion of the recess portion.

A display apparatus comprising:

• a display panel;
• and
• a backlight unit configured to provide a light to the display panel, the backlight unit comprising:
• a light source configured to emit the light;
• and
• a light guide plate comprising a light incident surface to which the light is configured to be incident, a light exit surface from which the light incident through the light incident surface is configured to exit, a bottom surface facing the light exit surface configured to reflect at least a portion of the incident light, and a scattering pattern disposed on the bottom surface,
• wherein the scattering pattern comprises:
• a first protrusion portion protruding from the bottom surface;
• a recess portion disposed along a circumference of the first protrusion portion and recessed from the bottom surface;
• and
• a second protrusion portion spaced apart from the first protrusion portion and disposed along a portion of the recess portion.

An extrusion roller for a light guide plate, comprising:

• a first body having a cylindrical shape and configured to rotate with respect to an axis;
• and
• a first outer circumference portion wrapping the first body along an outer circumference of the first body,
• wherein the first outer circumference portion comprises:
• a first outer circumference surface having a first radius with respect to axis;
• a second outer circumference surface having a second radius smaller than the first radius with respect to the axis;
• and
• a counter-slant surface connecting the first outer circumference surface and the second circumference surface.

A method of manufacturing a light guide plate, comprising:

• pressurizing a material using an extrusion roller to form a mother light guide plate;
• cutting the mother light guide plate to form a light guide plate comprising a light exit surface comprising a first flat surface, a second flat surface, and a slant surface;
• and
• forming a scattering pattern on an opposite surface to the light exit surface using a roll stamper.