Abstract: A vacuum-tight envelope (601) having a terminal element (610) bearing the envelope's output window. An output screen (605) is glued to the inner face of the output window by a first glue (608) having the same refractive index as the output window. The envelope's terminal element is made unitary with a (611) of the envelope by vacuum-tight mounting (609). An optional anti-reflection coating (674) may be deposited directly onto the external face of the output window.

Abstract: The thickness of the layer of luminescent material on the edges of the screen at approximately 1/10.degree. from the edge of the image field is approximately 15 to 25% smaller than its thickness at the center of the screen. Thus the length of the x-ray path within the luminescent material is substantially the same irrespective of the angle of incidence of the x-rays on the screen and, when the x-ray energy varies, the sensitivity at all points of the screen varies substantially in the same manner. The screen in accordance with the invention is primarily employed in digital radiology systems in which the same image is produced several times by utilizing different x-ray energies.

Abstract: The invention relates to a radiological image intensifier tube with a video output. The tube has in the same vacuum envelope an image section and an analysis section having a common face occupied by target. An electrical image corresponding to the incident X-ray image is formed in the image section and this image is read in the analysis section by an electron beam scanning the target point by point. This target has in the tubes according to the invention a structure making it possible to limit the X photon-video signal gain and to regulate it between two predetermined values. On its face which receives the photoelectrons e.sup.31 it has a metal barrier layer 1 covering a luminescent layer 2, in contact with a semitransparent layer 3 covering the actual target 4.