An optical adjusting member according to the invention includes a base member having optical transparency and a plurality of linear members provided on the base member and having optical transparency. A section of the linear member orthogonal to the lengthwise direction of the linear member includes a triangular first sectional part defined by first to third sides and an approximately triangular second sectional part. The second sectional part has a smaller area than that of the first sectional part and defined by fourth to sixth sides. The first side of the first sectional part is in contact with the surface of the base member. The second sectional part is formed on the second side of the first sectional part, and the fourth side of the second sectional part is in contact with the second side of the first sectional part.