US Patent 7877015 Optical to radio frequency detector

An optical to radio frequency detector comprises an optical guide for receiving two optical signal components having frequencies that differ by an amount corresponding to a radio frequency, and a radio signal guide coupled with an interaction zone of the optical guide for propagating a radio signal from the interaction zone at the radio frequency. The material of the interaction zone presents a second-order non-linear optical polarization characteristic to the propagation of the optical signal components, and the radio signal guide is in travelling-wave coupling with the interaction zone. A radio signal output is coupled with the radio signal guide.