Angular and spectral characteristics of a parametric converter of thermal radiation based on a lithium iodate crystal

The angles of noncntical phase matching and the spectral reception band were calculated and measured for a parametric infrared radiation (1–6 μ) converter based on a lithium iodate crystal. The signal was in the form of Globar radiation and the pump radiation was provided by a ruby or neodymium-glass laser. The maximum width of the reception band in the 4.2 μ range was 470 ± 50 cm^–1 when the conditions of noncntical phase matching and dispersion matching were satisfied simultaneously. Conversion of images of thermal objects emitting in the 1–3 μ range was possible with a resolution of 5 lines/mm.