infrared imaging system with a device for compensating the temperature influence on the fokussierzustand.

摘要

In order to eliminate the influence of temperature on the focus of an IR optical imaging system, radiation from an auxiliary heat source is deflected through the IR optical imaging system such that said radiation impinges on an autocollimating reflector from where it is reflected back into said IR optical imaging system and then impinges on detector elements which are arranged in a detector image plane. Electrical signals generated by the affected detectors are analyzed, digitized, and then compared in a computer whose output signals control a motor for adjusting the axial position of at least one of the optical lens elements of the IR system such that the autocollimating condition between the auxiliary heat source and its image in the detector plane is maintained at all times.