History of Computers - CRT
Page created by Michael Bloom
Introduction
The CRT or Cathode Ray Tube was the primary apparatus in video screens in televisions and monitors up until the relatively modern advent of newer more compact technologies such as LCD televsion and plasma.
Overview
While scientists had been experimenting tentatively with cathode rays for a few decades, the first cathode ray tube that actually became a forerunner to the late 20th century cathode ray tube was the Braun tube. Invented by Karl Braun in 1897, the Braun tube used a focused beam of electrons to light up a fluorescent screen when the two contacted, emitting a visible dot of light where ever the beam was aimed.[1] The beam of electrons, due to the negative charge of the particles, are controlled using a magnetic field which can either attract or repel the beam, depending on the negative or positive charge of the magnet.[2] Braun also expanded the basic Cathode Ray Tube into a Cathode Ray Oscilloscope, which takes electrical signals and displays those signals upon the fluorescent screen. This oscilloscope provides the basis for the Cathode Ray Tubes of the relative future. This technology was not perfect though and the first Cathode Ray Tube to display a signal well was invented by Vladimir K. Zworykin and was used in a primitive TV screen.[3] The technology behind the CRT continued to increase and future versions of the CRT able to project millions of colors of pixels. [4]
Significance
The CRT is one of the most important inventions in computing. It was the first feasible way to display an image from a computer and despite later being overtaken by the LCD televsion, it was still a huge stepping stone. Early computers' displays were a series of flashing lights.[6] If the CRT was not developed computer displays would have never reached the same level as they have now. Also the GUI would never have created and the accessibility of computers would not have increased to levels that make it such an integral part of life. Thus, thanks to the impacts it made the CRT is an important part of computer history. The CRT still has relevance to modern society in that display lag is extremely low for the CRT, which does not have the ability to store image data before display, making the CRT used widely in the competitive gaming community. [1]
References
http://en.wikipedia.org/wiki/Display_lag
- ↑ http://theinventors.org/library/inventors/blcathoderaytube.htm
- ↑ http://www.gizmohighway.com/history/crt.htm
- ↑ http://theinventors.org/library/inventors/blcathoderaytube.htm
- ↑ http://theinventors.org/library/inventors/blcathoderaytube.htm
- ↑ http://www.phywe.com/461/pid/2250/Braunsches-Rohr-mit-Fassung-.htm
- ↑ http://www.pcworld.com/article/209224/a_brief_history_of_computer_displays.html
