Charactron

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Basic Charactron tube design Charactron layout 1.jpg
Basic Charactron tube design

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. [1]

United States Patent and Trademark Office agency in the United States Department of Commerce

The United States Patent and Trademark Office (USPTO) is an agency in the U.S. Department of Commerce that issues patents to inventors and businesses for their inventions, and trademark registration for product and intellectual property identification.

Convair 1943-1996 aerospace manufacturer

Convair, previously Consolidated Vultee, was an American aircraft manufacturing company that later expanded into rockets and spacecraft. The company was formed in 1943 by the merger of Consolidated Aircraft and Vultee Aircraft. In 1953 it was purchased by General Dynamics, and operated as their Convair Division for most of its corporate history.

Contents

The Charactron CRT used an electron beam to flood a specially patterned perforated anode that contained the stencil patterns for each of the characters that it could form. The first deflection positioning of the electron beam steered the beam to pass through one of the (typically 64 or 116) characters and symbols that could be formed. The beam, which then had the cross-section of the desired character, was re-centered along the axis of the tube and deflected to the desired position of the screen for display. 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.

Monoscope

A monoscope was a special form of video camera tube which displayed a single still video image. The image was built into the tube, hence the name. The tube resembled a small cathode ray tube (CRT). Monoscopes were used beginning in the 1950s to generate TV test patterns and station logos. This type of test card generation system was technologically obsolete by the 1980s.

Applications

There were two basic types/uses of Charactrons:

  1. Direct view — where the intended user watched the face of the tube. An example was the 19-inch-diameter (480 mm) tube of the AN/FSQ-7 SAGE Semi Automatic Ground Environment computer console.
  2. Photographic output — where the display screen was photographed by a microfilm camera for recording of computer generated data. The Stromberg-Carlson SC-4000 series system was a typical use of the 5-inch-diameter (130 mm) tube

The technical expertise, and trademarks, for the Charactron ultimately passed to Stromberg-Carlson, General Dynamics, Stromberg DatagraphiX, Anacomp, and finally Lexel Imaging Systems.

Stromberg-Carlson was a telecommunications equipment and electronics manufacturing company in the United States. It was formed in 1894 as a partnership by Alfred Stromberg and Androv Carlson. It was one of five companies that controlled the national supply of telephone equipment until after World War II.

General Dynamics Corporation (GD) is an American aerospace and defense multinational corporation formed by mergers and divestitures. It is the world's fifth-largest defense contractor based on 2012 revenues. The company ranked No. 99 in the 2018 Fortune 500 list of the largest United States corporations by total revenue. It is headquartered in West Falls Church, Fairfax County, Virginia.

Anacomp

Anacomp, Inc., is an American company that specializes in computer services and document management. It was founded in Indianapolis, Indiana, in 1968 by Ronald D. Palamare, Robert R. Sadaka, and J. Melvin Ebbert, three professors at Purdue University. Their goal was to direct the power of the computer toward the disciplines of investment management, education, urban analysis, computer science and civic systems, but is now headquartered in Chantilly, Virginia. The name Anacomp is a combination of the words ANAlyze and COMPute. Since its inception, Anacomp has made many acquisitions and spin-offs and has entered and exited different lines of business.

Patents

See also

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References

  1. "Typotron, 5" character-writing CRT-type storage tube data sheet" (PDF). Hughes Aircraft Corporation. 24 November 1954. Retrieved 29 August 2017.