Patent ID: 6843587

Claim:
A surface light source apparatus comprising: a light guide panel configured to scatter and diffuse light at a uniform brightness in an entire area and a light guide pattern portion having a plurality of grooves satisfying an equation that d ⁡ ( μ ⁢ ⁢ m ) × w ⁡ ( μ ⁢ ⁢ m ) p ⁡ ( μ ⁢ ⁢ m ) = 25 ∼ 65 , wherein ⁢ ⁢ the ⁢ ⁢ range ⁢ ⁢ of ⁢ ⁢ t ⁡ ( mm ) S ⁡ ( mm 2 ) ⁢ ⁢ is ⁢ ⁢ 6 × 10 - 5 ∼ 1.2 × 10 - 4 , wherein t is a thickness of the light guide panel, S is an area of a process surface of the light guide panel, d is a process depth of the light guide pattern portion, w is a line width of each groove of the light guide pattern, and p is a pitch between the grooves of the light guide pattern portion, and at least one light source installed at one side wall of the light guide panel and emitting light to the light guide panel.