Optical body, wall member, fitting, solar shading device, and building

An optical body comprising:na substrate having a concave-convex surface;a reflecting layer formed on the concave-convex surface; andan optical layer formed on the reflecting layer to embed the concave-convex surface,wherein the reflecting layer directionally reflects all of the incident light regardless of the wavelength band,the concave-convex surface is made up of a plurality of triangular pillars arrayed in a one-dimensional pattern, andthe triangular pillar has an apex angle α and a slope angle β, the apex angle αand the slope angle β being within an area bounded by lines defined by the following formulae:nβ=4.5α−285(where 70≦α≦80)nβ=−1.5α+195(where 80≦α≦100) andnβ=30.

An optical body comprising:na substrate having a concave-convex surface; anda reflecting layer formed on the concave-convex surface,wherein the reflecting layer directionally reflects all of the incident light regardless of the wavelength band,the concave-convex surface is made up of a plurality of triangular pillars arrayed in a one-dimensional pattern, andthe triangular pillar has an apex angle α and a slope angle β, the apex angle αand the slope angle β being within an area bounded by lines defined by the following formulae:nβ=4.5α−285(where 70≦α≦80)nβ=−1.5α+195(where 80≦α≦100) andnβ=30.