A reflective electrode substrate (1) comprises a supporting member having a plurality of first fundamental surfaces (Sf) each having portions (K1, K2) differing in their height, a plurality of undulating portions (18 to 128) formed on the supporting member arranged in the x direction at a undulating portion pitch (Tx) and a plurality of reflective electrodes (Er1, . . . , Eg6). The plurality of fundamental surfaces (Sf) are arranged in the x direction at the pixel pitch (Sx) and the undulating portion pitch (Tx) is a non-integral multiple of the pixel pitch (Sx).