Tapered velocity electro-optical waveguide switch

Claim 1

A four part electro-optical switch for selectively switiching radiation from one light path to another comprising: a substrate of an electro-optic material; a first optical waveguide; a second optical waveguide; said waveguides being spaced from each other and paralleling each other along the major portion of their length with the ends of said waveguides diverging from each other; at least one pair of curved electrodes with one electrode disposed on said substrate along the outer surface of each of said waveguides with one end adjacent a divergent end with the opposite end of each of said electrodes curved away from its adjacent waveguide; an electrode disposed on said substrate equidistant between said waveguides, said electrode including a first and second end; means for connecting a first voltage source to said first end of said third electrode and to the end of one of said curved electrodes which end is curved away from said waveguide, adjacent to said curved electrode; means for connecting a second voltage source to the second end of said third electrode and to the end of the other electrode of said pair of electrodes which end is curved away from is adjacent waveguide, whereby in the "on " state the voltage of said first and second sources is applied so that the difference in propagation constant between said waveguide channels varies slowly over their length changing sign in the mid-point of their length thereby switching optical radiation from one waveguide to the other.