A circular-shaped back light having pattern diffused reflection

摘要

PURPOSE: A circular light guide plate having a scatter pattern is provided to overcome a limitation of the existing tetragonal light guide plate by introducing the circular light guide plate having a predetermined pattern, thereby enabling various designs in display devices, illuminating and surface light source devices. CONSTITUTION: In a circular light guide plate(20) having a ring type light source(40) installed at the edge, the circular light guide plate includes a scatter pattern(20a) formed at the bottom surface of the light guide plate and that the size of the scatter pattern or a coating rate is gradually being decreased as the scatter pattern becomes more distant from the light source with moving into the center of the circle from the edge where the light source is placed.