LED display

An LED display is a flat panel display, which uses an array of light-emitting diodes as pixels for a video display. Their brightness allows them to be used outdoors in store signs and billboards, and in recent years they have also become commonly used in destination signs on public transport vehicles. LED displays are capable of providing general illumination in addition to visual display, as when used for stage lighting or other decorative (as opposed to informational) purposes.

History

The first true all-LED flat panel television screen was possibly developed, demonstrated and documented by James P. Mitchell in 1977. The modular, scalable display was initially designed with hundreds of MV50 LEDs and a newly available transistor-transistor logic memory addressing circuit from Texas Instruments. The ¼-inch thin flat panel prototype and the scientific paper were displayed at the 29th ISEF expo in Washington D.C. in May 1978. It received awards by NASA and General Motors Corporation. A liquid crystal display (LCD) matrix design was also cited in the LED paper as an alternative x-y scan technology and as a future alternate television display method. Additional recognition was provided by Westinghouse Educational Foundation "Honors Group" and the concept prototype was also a selected scientific paper at the Iowa Academy of Science of the University of Northern Iowa. The replacement of the 70 year+ high-voltage analog system (cathode-ray tube technology) with a digital x-y scan system has been a significant achievement. Displacement of the electromagnetic scan systems included the removal of inductive deflection, electron beam and color convergence circuits. The digital x-y scan system has helped the modern television to “collapse” into its current thin form factor.