Backlight unit of a liquid crystal display device and method for fabricating a light guided panel of the same

A backlight unit of an LCD(Liquid Crystal Display) and a method for manufacturing a light guide panel of the backlight unit are provided to form plural prism V-shape grooves and mountains on a side of the light guide panel and to form plural dot patterns to the other side of the light guide panel. A light guide panel receives the light beam from a light source. An optical sheet transmits the light beam from the light guide panel to an LCD panel. Plural V-shape grooves(137) are formed on a surface of the light guide panel. The width and depth of the groove are gradually increased away from the light source. Plural dot patterns(138) are formed at the other surface of the light guide panel. The light source is constructed by any one of a cold cathode tube and an LED(Light Emitting Diode). The cross-section of the V-shape groove has a triangle shape and the vertex angle thereof is about 90 to 120 degrees. The dot patterns are arranged irregularly. The optical sheet includes a diffusion sheet for receiving the light beam from the light guide panel. One or more prism sheets receive the light beam from the diffusion sheet.