In this case, the ELO device surfaces may also be coated by metal also, such as shown in an example described below with respect to FIGS. 82-89. [0187] In order to form a three-dimensional waveguide that is optically coupled to the p-i-n waveguide of the ELO segments, core layer 24 and clad layer 23 are successively formed using the above-described liquid polymer coating steps, as shown in FIG. 77