Patent ID: 8400703

Claim:
An optical switch for switching between transmission and total reflection of incident light applied to an electro-optical crystal by applying an electric field to the electro-optical crystal to thereby change the refractive index of the electro-optical crystal, comprising: an electrode assembly for applying an electric field to said electro-optical crystal, said electrode assembly comprising a plurality of electrodes disposed in said electro-optical crystal; wherein said electro-optical crystal has a refractive index changing portion whose refractive index is reduced by the electric field applied by said electrode assembly, irrespective of directions of the electric field, said refractive index changing portion enclosing said electrode assembly in its entirety, and said refractive index changing portion has a flat refractive index boundary face, wherein a total reflection surface is formed at an interface between the refractive index changing portion and a surrounding region of the refractive index changing portion by the electric field applied by the electrode assembly.