An infrared thermometer (10) with a fixed aperture (99), focusable remote pickup head (12) conveys infrared light (16) from a target (14) to a photosensor (52) of a defocused sensor head (20). The remote pickup head (12) has a reimaging lens (84) and means for selectively adjusting the focus of the lens...http://www.google.com/patents/US5011296?utm_source=gb-gplus-sharePatent US5011296 - Method of using infrared thermometer with remote fiber optic pickup
