Abstract: A thermal imaging device is provided, comprising: a detector for receiving radiation and outputting a detector signal corresponding thereto; a steerable mirror device arranged in relation to the detector; wherein the steerable mirror device is steerable to scan an entrance pupil over a plurality of locations such that the detector outputs respective detector signals indicative of temperatures of respective portions of the object corresponding to the locations of the entrance pupil, and wherein the thermal imaging device is configured to provide a substantially constant etendue for all of the entrance pupil locations of the plurality of entrance pupil locations.

Abstract: A radiation thermometer is provided, comprising: a thermal radiation detector assembly having an operative surface area responsive to thermal radiation of a first wavelength; a focussing optics assembly adapted to focus both thermal radiation of the first wavelength and visible light of a second wavelength along an optical axis, the focussing optics assembly being configured to form a focussed image of the operative surface area of the thermal radiation detector assembly on a focal plane outside the radiation thermometer, the focussed image of the operative surface area defining a target region from which the thermal radiation detector assembly detects thermal radiation; a visible light source assembly adapted to exhibit an illuminated pattern of visible light of the second wavelength, the visible light source assembly comprising at least one visible light source and a mask through which light from the at least one visible light source is arranged to pass, the mask having one or more substantially opaque port