Two-dimensional electro-optic imaging of THz beams

We report on a novel electro-optic sampling system for real-time terahertz (THz) imaging applicators. By illuminating a 6 x 8 mm(2) ZnTe crystal with a 300 mu W optical sampling beam and detecting the beam with a digital CCD camera, we achieved time-resolved images of pulsed far-infrared radiation emitted from an unbiased GaAs wafer. At the focal point of the peak far-infrared field, the THz beam diameter is approximately 0.75 mm (full width at half-maximum). The temporal and spatial resolutions of this imaging system are mainly limited by the laser pulse duration and the diffraction limit of the THz beam, respectively. (C) 1996 American Institute of Physics.