| 摘要 |
A surface light source device includes a number of light sources, a first prism sheet and a second prism sheet. The light sources are distributed on a bottom plate of a housing. The first prism sheet and the second prism sheet are arranged above the light sources in that order. The light sources and the first prism sheets are spaced by a first predefined distance, and the first prism sheets and the second prism sheets are spaced by a second predefined distance. The light emitting surface of the first prism sheet includes a number of substantially parallel elongated protrusions, and the light emitting surface of the second prism sheet includes a number of elongated V-shaped ridge structures extending along different directions. Light beams emitted by the light sources are substantially diffused after passing through the first and the second prism sheet and become surface light beams. |
