SED, which stands for ‘Surface-conduction Electron-emitter Display’ could be an upcoming technology in the television industry. SED televisions are much awaited since many years and first prototype was expected to introduce in 2004 by Toshiba, who was working on SED since more than 10 years. SED seems to be inherited from TFT and CRT monitors. It combines the thinness of the first and the qualities of the second and improves them.
It draws less power and the best feature is that it does not require backlights, as LCDs do. Like Cathode Ray Tube TVs, SED technology is based on the collision of electrons and phosphoric monitor to emit light. Still, unlike CRTs, there is not a single gun for the monitor, but a mini electron gun behind each sub-pixel, 1920 x 1080 x 3 = 6.2 million of guns and each sub-pixel is covered with phosphorus. Electrons emitted by transmitter hit the panel phosphor and produces light.
Major feature of SED television is their viewing angle, which is complete 180° with the response time of less than 1 millisecond and contrast ratio of 100,000:1. Canon demonstrated the prototype of SED TVs jointly with Toshiba Corp in 1999 and to emphasize the advantages, it organized a test room with the SED placed between plasma and a LCD TV and the result for SED was nothing comparable to any of the other technological display. In May 2010, Canon announced it planned to keep working on the technology for business uses, such as medical displays, but said the technology was not profitable in TVs as LCD and plasma had fallen too quickly in price and initial production cost is too high while the selling rate is not at all affordable. Now, let us see when SED display will hit the market at least for business users.