OPTICAL SHEET WITH REDUCED DEFECT VISIBILITY, FILTER INCLUDING THE SAME, AND IMAGE DISPLAYING DEVICE INCLUDING THE OPTICAL SHEET OR THE FILTER

摘要

Disclosed are an optical sheet, a filter including the same, and an image display device including the optical sheet or the filter. The optical sheet includes a light transmission portion including a plurality of grooves spaced apart from each other at an end of the light transmission portion corresponding to an image light source side or an observer side; and a plurality of external light absorption portions which fill the grooves and include a light absorbable material, wherein at least one part of each of the grooves that is not filled with external light absorption portion forms a recess portion having one open side, and a difference ?d between maximum depths of two recession portions that are adjacent to each other among the recession portions satisfies the following condition: 0.01 ? = |?d| = 1 ?.