A substrate is provided with a light reflection film in which the heights of a plurality of convex portions or the depths of concave portions formed on a base material are specified to be substantially the same. The two-dimensional shapes of the plurality of convex portions or concave portions are specified to be the two-dimensional shapes of independent circles and polygons, or of either of them. In addition, the plurality of convex portions or concave portions are arranged in the direction of the plane on a random basis. The substrate is formed using a mask in which light transmission portions or light non-transmission portions are formed in units of dots, the number thereof being smaller than the number of dot regions. The dots are arranged irregularly in each of the units, and a plurality of units are included.