ELECTRO-OPTICAL AND MAGNETO-OPTICAL SENSING APPARATUS AND METHOD FOR CHARACTERIZING FREE-SPACE ELECTROMAGNETIC RADIATION

摘要

Apparatus and method for characterizing free-space electromagnetic energy, suitable for real-time two-dimensional far-infrared imaging applications. The sensing technique is based on a non-linear coupling between a low-frequency electric or magnetic field (12) and a laser beam (16) in an electro-optic or magnetic-optic crystal (14, 32 or 54). A counter-propagating sensing technique (Fig. 1), and a co-linear sensing technique (Figs. 4 and 13) are described for longer radiated and optical beam interaction length, making imaging applications practical.