Since the inception of the image dissector, the first practical image tube in the early 1930\´s, camera tubes have undergone steady improvements in resolution, reliability, and sensitivity. The use of these tubes in such applications as television broadcasting, the space program, medical electronics, and the observation of astronomical phenomena has led to a broad and diverse family of imaging devices. The allied field discussed, the display storage tube, has been developed in the last

decades to combine information storage and directly viewed display. Display storage tubes are used extensively in radar indicators and other applications requiring high brightness, controllable persistence, and signal-to-noise improvement. Signal storage tubes are used for scan conversion, digital storage, signal processing, and many other related applications. Increased use has led to the development of high-performance tubes in very small packages.