A vanadium dioxide display tube

Vanadium dioxide is shown to be, useful as a display medium in electron tubes with applicability as large area displays, storage tubes and "page composers". The utility of VO2in this role is a consequence of the large decrease in the index of refraction at 67°C. Even though the absorption coefficient is large, design criteria are established which can produce two color displays of a variety of colors with reflectances as high as 70% and contrast ratios as high as 30:1. Measurements have shown better than 200 line pairs per mm resolution with a sensitivity of better than 4 mJ/cm². Design details and performance data will be presented for a CRT capable of recording a standard television frame in a single scan. The image is stored without degradation of resolution or contrast until it is erased. Full erasure can be accomplished in a few seconds, with this design.