OPTICAL SHEET, SURFACE LIGHT SOURCE DEVICE, VIDEO SOURCE UNIT, AND DISPLAY DEVICE

摘要

PROBLEM TO BE SOLVED: To provide an optical sheet that can improve efficiency of use of light from a light source.SOLUTION: There is provided an optical sheet (26) used in a liquid crystal display device, and comprising a substrate (35) and an optical function layer (30) that is laminated on one face of the substrate, where the optical function layer includes: light transmission parts (31) that each have a predetermined cross section, extend in one direction along a surface of the substrate, and are arranged in plurality at an interval in a direction different from the direction to extend; and light reflection parts that are formed in the intervals between the plurality of light transmission parts. The light reflection part includes means that regularly reflects light on a boundary face with the light transmission part.SELECTED DRAWING: Figure 4