Abstract: The invention relates to a device for measuring the electromagnetic radiation of a radiating object (10), comprising: a sealed box (20) housing said radiating object (10); means (12) for moving said radiating object (10) in a longitudinal direction (L); a heat-sensitive film (14) housed in said box (20); a camera (16) housed at a longitudinal end of said sealed box (20), opposite said radiating object (10) to be measured relative to the heat-sensitive film (14), and configured to acquire images of said heat-sensitive film; means (18) for processing said images configured to provide a map of the electromagnetic field of said radiating object (10) picked up by said heat-sensitive film (4).