Abstract: Temperature profiles of objects having large areas are measured and displayed by providing a plurality of radiometric sensors, each sensor having an established field of view and being directed toward the object whose temperature is being measured. Outputs of the sensors are processed to provide maximum sensitivity within a specified temperature range and little or no sensitivity outside of the specified range. Within a specified temperature range the temperature scale is divided into a number of increments, the number of said increments dependent on the desired degree of resolution of measurement. The processed and expanded output of each of the radiometric sensors is electronically compared and categorized into the selected divisions of the specified temperature range. Electrical signals derived from this comparison are provided to columnar displays associated with each radiometric sensor whereby the range of temperature is displayed and the output of each radiometric sensor is indicated.

Abstract: Infra-red images are projected onto an infra-red detector whose output is amplified, linearized, digitized and displayed as a numerical value corresponding to the temperature of the object viewed by the infra-red optical system. The optical axis of the infra-red optical system is coaxial with the optical axis of a visible light optical system which is used for sighting and aligning the field of view of the infra-red optical system with the object. Through the eyepiece of the visible light optical system an observer sees the object, the scene area surrounding the object and the numerical value of the temperature of the object as indicated by a digital readout whose image is superimposed over the scene.