Patent ID: 7283704

Claim:
An optical signal to electrical signal converter comprising: an optical waveguide for receiving and propagating an optical signal that has been modulated so as to have a side band represented by: λ sb =λ C +Δλ Δλ=λ C -(Cλ C /(C+f m π))=f m λ c 2 /(C+f m λ C ) where f m is the frequency in Hertz (Hz) of the modulating signal, λ sb is a wavelength at which the side band generates, C is the velocity of light, and λ c is the center frequency of the light; and a pair of electrodes disposed within a region where an electric field applies, said electric field being generated in the optical waveguide by a nonlinear optical effect when the optical signal propagates through the optical waveguide, wherein the optical waveguide is formed on a dielectric substrate or in the dielectric substrate, and wherein the pair of electrodes are provided on a top surface of the dielectric substrate, said pair of electrodes being opposite to each other with the optical waveguide interposed between the electrodes, wherein the optical signal is incident on a side surface of the dielectric substrate parallel to the longitudinal direction of the pair of electrodes, and wherein when the optical signal is incident on the side surface of the dielectric substrate, a variation in the electric field generated in the optical waveguide is output as an electrical signal from the pair of electrodes.