(under subclass 326) Subject matter wherein the frequency conversion of electromagnetic radiation, in the near and the visible spectrum, is based on the nonlinear dependence of polarizability on wave amplitude.
(1) Note. A parametric oscillation is an oscillation in which substantial power is applied at a frequency called the pump frequency. Signal and idler waves, the sum of whose frequencies equals the pump frequency, are generated in an interaction resulting from some nonlinear effect in the optical crystal.
