Abstract

In coherent CO₂ laser radars, it is often desirable to track out the target translational Doppler frequency by shifting the laser LO. A single sideband (SSB) electro–optic (EO) modulator can be used for this purpose. The output from the SSB EO modulator considered here^1,2 is high in mode quality and spectral purity. However, the bandwidth is limited by the dispersion of the modulation circuit. The new scheme described here (see Fig. 1) uses a ferrite-loaded waveguide containing an active CdTe EO crystal. A wide tuning range can be achieved by changing the phase velocity of the composite waveguide with an applied magnetic field.

© 1991 Optical Society of America