Patent ID: 8488081

Claim:
A plane light source including light emitting device matrixes each having a plurality of light emitting devices arranged in rows and columns on a substrate, the plane light source comprising: a first matrix having a plurality of light emitting devices arranged in rows and columns; a second matrix having a plurality of light emitting devices arranged in rows and columns, the light emitting devices each located within a rectangle formed by four adjacent light emitting devices included in the first matrix, and forming angles θ satisfying the condition of 45°≦θ≦55° therebetween on the basis of a horizontal direction; a side wall located at the edges of an upper surface of the substrate encompassing the plurality of light emitting devices, the side wall having an inclined surface; and a reflective layer formed on the substrate, the reflective layer reflecting from the plurality of light emitting devices, wherein among pitches between one light emitting devices included in the light emitting device matrixes and another lighting light emitting device adjacent to the light emitting device, a pitch P 1 between the light emitting device and the light emitting device diagonally across from the light emitting device satisfies the condition of 25 mm≦P 1 ≦29 mm, and a pitch P 2 between the light emitting device and another light emitting device located in a horizontal direction satisfies the condition of 34 mm≦P 2 ≦38 mm.