BUT: Surface Conduction Electron Emitter Display. Refers to a screen technology developed by Canon. SED technology tries to take advantage of displays on CRT -, LCD - and Plasma – Unite base. Similar to picture tubes, SEDs also have electron emitters, but with this technology there is one emitter for each pixel responsible. If you now turn on the device, electrons are emitted and in the electric field between the with Phosphorus coated glass that forms the screen and the emitters.
The phosphor on the glass serves as a light source. The main advantages of this technology are that it offers similarly fast response times and true-to-nature color reproduction as CRT screens have. Since the electron beams do not have to be deflected here, there is no deflection system, so the screens are as thin as liquid crystal and plasma screens.
Due to the light source used, burn-in of the image content can also occur here. In addition, in contrast to LCD or plasma displays, X-ray radiation is also emitted during use.