Charactron

Charactron was a U.S. registered trademark (number 0585950, 23 February 1954) of Consolidated Vultee Aircraft Corporation (Convair) for its shaped electron beam cathode ray tube.

Charactron CRTs performed functions of both a display device and a read-only memory storing multiple characters and fonts.

The similar Typotron was a U.S. registered trademark (23 November 1953) of Hughes Aircraft Corporation for its type of shaped electron beam storage tube with a direct-view bistable storage screen.

Alternately, as in the accompanying image, the entire matrix was filled with the electron beam then deflected through a selection aperture to isolate one character.

The term Charactron is sometimes mistakenly applied to another type of CRT properly called a monoscope which generates an electrical signal by scanning an electron beam of uniform cross section across a printed pattern on an internal target electrode.