A flat alphanumeric display tube

A unique alphanumeric display has been developed which utilizes several digitally addressed electron beams to write characters on a conventional phosphor target. The electron beams are generated by an areal electron source, followed by a series of thin dynode plates containing any array of holes. The plates act collectively to control the flow of electrons spatially, so that several electron beams from certain holes in the last plate at discrete positions determined by the digital addressing signals. This device incorporates the features of flat-panel construction, digital address, simplified electronics, multibeam operation, and low power. In addition, the concept is applicable to multicolor operation, gray scale modulation, and graphics presentations. The principles of operation of a 64-character display (8 rows of 8 characters per row) are discussed in detail. In addition, the actual operational characteristics of a 176-character DIGISPLAY® are given, along with an analysis of the power requirements of this display.