An electron tube that produces on its fluorescent screen an image of the irradiation pattern of its photosensitive input surface. An image converter which produces an image with enhanced radiance is sometimes called an image intensifier.
Source:
PAC, 1995, 67, 1745. 'Nomenclature, symbols, units and their usage in spectrochemical analysis-XI. Detection of radiation (IUPAC Recommendations 1995)' on page 1758 (https://doi.org/10.1351/pac199567101745)