A Dynamically Regenerated Electrostatic Memory System

In an electrostatic memory system, the words are stored as charge patterns on the screen of a cathode-ray tube. Memory is extended by a systematic regeneration process. All experiments were performed on a standard cathode-ray tube. This paper discusses the fundamental theory behind electrostatic storage. The principal problem was that of finding a method for storing the charges such that two easily and reliably distinguishable states could be established at various points on the face of the tube. After experimenting with various patterns, a dot-circle combination was chosen as superior to all those tested. The dot, representing binary one, is generated by sharply focusing the beam on a spot. The circle is generated by imposing high-frequency sinusoidal electromotive forces, 90° apart, on the vertical and horizontal deflection plates. The paper then offers a comparison of the dot-circle pattern with the several other systems of electrostatic storage now under test. The details of numerous experiments are given, together with a description of the apparatus used for test. The effects of phospbor type, gun structure, tube diameter, accelerating voltage, leakage, transients, and other factors affecting memory are discussed. The concluding section of the paper describes the various types of large capacity high-speed memory designs which could be constructed from a reliable electrostatic memory tube.