Final answer:
The input phosphor of modern image intensifier tubes is typically made of cesium iodide. Older CRT technologies can generate low-intensity X-rays, which are shielded in consumer devices. Scintillators convert light into electrical signals, useful in medical imaging technologies.
Step-by-step explanation:
The input phosphor of modern image intensifier tubes is typically made of cesium iodide (CsI). These phosphors are used to convert incoming X-ray photons into visible light, which can then be converted into an electric signal by a photomultiplier tube. Using materials like cesium iodide allows for efficient conversion due to its high conversion efficiency and good resolution.
When discussing older technologies such as CRTs (cathode-ray tubes), they do use high accelerating potentials, around 30-kV, to send electrons to the screen. This process stimulates phosphors to emit light and create the image we see. As for the production of X-rays, yes, some X-rays can be generated due to the high-energy electrons hitting the screen, but they are typically of low intensity and are adequately shielded in consumer devices.
In the context of light conversion, certain materials mentioned, such as sodium oxide (Na₂O), cadmium sulfide (CdS), are chemical compounds of interest in different technological applications but not specifically related to the construction of image intensifier tubes' input phosphor. Scintillators, like cesium iodide, work in tandem with photomultiplier tubes to convert light from gamma cameras into electrical signals, providing valuable medical imaging data.