Figure 1. Conceptual illustrations of the conventional random surface and the proposed controllable random surface.

(a,b) Schematics for the conventional random surface and the proposed controllable random surface. (c) Schematic illustration for the generation of the mixed coding pattern (the right pattern) of the controllable random surface from the addition of a periodic coding sequence “01230123…” (the middle pattern) and a random coding sequence (the left pattern).