DVBST

DVBST was an acronym used by Tektronix to describe their line of "Direct-View Bistable Storage Tubes". These were cathode ray tubes (CRTs) that stored information written to them using an analog technique inherent in the CRT and based upon the secondary emission of electrons from the phosphor screen itself. (See the discussion of "Analogue Storage" in the oscilloscope article.) The resulting image was visible in the continuously glowing patterns on the face of the CRT.

DVBST technology was anticipated by Andrew Haeff of the (United States) Naval Research Laboratory, and by Williams and Kilburn in the late 1940s. Tek's Bob Anderson reduced to practice the science and technology in the late 1950s to yield a reliable and simple DVST.

DVBSTs were used for analog oscilloscopes (first in the 564 oscilloscope, then the 601 monitor, the 611 monitor, the 7613 plug-in mainframe oscilloscope, all from Tektronix) and for computer terminals such as the archetypical Tek 4010 (the "mean green flashin' machine") and its several successors including the Tektronix 4014. Portions of the screen are individually written-to by a conventional electron beam gun, and "flooded" by a wide, low velocity electron gun. Erasure required erasing the entire screen in a bright flash of green light, leading to the nickname.

Some DVBST implementations also allowed the "write-through" of a small amount of dynamically refreshed, non-stored data. This allowed the display of cursors, graphic elements under construction, and the like on computer terminals.