Reference radiation source in a device for measuring the radiation from an object

摘要

A device for measuring the radiation from an object by means of an optical system. The optical system comprises scanning devices for horizontal and vertical scanning with refracting rotating prisms. At least one radiation reference source is arranged in the optical system along the path of radiation from the scanned object so that the radiation source can be scanned by the rotating prisms at intervals which are not coincident with the interval when the object is scanned.