A temperature detection system includes a housing, a thermal imaging system at least partially disposed within the housing, an arm operably coupled with and extending from the housing, and a reference illumination system operably coupled with the arm. The thermal imaging system is adapted to capture at least one thermal image of a subject. The reference illumination system includes a substrate having at least one reference calibration unit operably coupled therewith such that the substrate is at least partially constructed from a solid metal embedded therein. The at least one reference calibration unit is visible to the thermal imaging system.