SED televisions are a type of flat panel display. Each pixel is displayed as an individual phosphor-based cathode ray tube. They use smaller versions of a CRT to display color per pixel. This allows these types of TV to be slimmer than their larger counterparts and more like LCDs or plasma televisions. Many believe that SED TVs also use less electricity to run because of their compact design.

This technology was developed by Canon in the late 1980s. They begin the research in the field and partnered with Toshiba to begin mass production of SED TVs in 2005. However, this goal was not met. In 2006, though, Toshiba did demo several SED prototypes to members of the Consumer Electronics Show. Again, Toshiba and Canon partnered up to produce these types of televisions for consumer purchase. They should begin release in late 2008 if all goes according to plan, even during their absence at the 2007 CES in Las Vegas, according to Toshiba.

SED TVs use surface conduction electrons to produce light over a thin set of electron tunnels when exposed to voltage. When the electrons pass through slits in the tunnels, they are put towards the surface of the display when electrified. Ink jet technology is used to spray phosphors onto glass to display the picture. They are very similar to a traditional CRT TV. One electron gun, so to speak, fires the phosphors that create the digital image produced.

SED essentially uses a bunch of "small CRTs," so to speak, to create its picture. These are called surface conductors. They are microscopic and have a slit down the center where light can pass through. When one part of the carbon layer interacts with a negative electrode, the other side connects to the positive electrodes. Each matrix controls the different colors, red, green or blue and a single pixel of picture. The picture is created equally distributed this way to create a single picture that is clear, crisp and bright.

Any pixel area of the screen that is not being used is black, and this adds to the contrast of the overall picture you are viewing. It also helps cut down on the contrast from light in a room. When the SED TV receives a signal, it decodes it first then distributes the phosphoric colors where they are needed where black then fills in the empty spaces. The vacuum then activates the right sequences and they distribute it to the screen so that you have a picture.

These types of TVs are expected to last more than 60,000 hours during accelerated tests. As long as the phosphors stay in tact, the television will continue to produce a vibrant color scheme and contrast. These types of results should be taken with a grain of salt, but if they are any indication of the future of SED TVs, it may prove to be a worthwhile investment. In comparison to a CRT model, which uses one electron gun that scans side-to-side, it can get bulky the larger it gets. SEDs do not need to be built like that, and this allows for a thinner and more manageable display the larger it gets. CRTs also wrap the end of the the display wheres an SED would not.

When it comes to comparing a SED to a traditional LCD display, latency is one of the biggest disparaging points. LCDs have always had a latency problem, but most TVs also have one, it is just not as noticeable. In order to update the picture, a TV generally needs 16 m/s of speed to keep a 60 Hz screen updated so that the picture does not lag. A SED uses one m/s of speed to update the picture; lag is non-existent. Since LCDs use a beam of directional light, this can cause problems due to viewing angles and when the axis is off center. This causes a slight lag that over time can disrupt viewing. Since SEDs use self-illuminated phosphors, lag time does not exist in any way that would cause problems continuously viewing

LCDs, however, do not have to worry about burn in whereas a SED does. Burn has always been a problem for plasma displays, because the use of phosphors being displayed in the same place over time causes the color to burn itself into the screen permanently. This can be avoided if your television is taken care of, but over time, burn in naturally occurs the more you use your TV. This is one of the major pitfalls of a SED-type TV.

SED technology is very new, despite it being developed over the years, and not much is known how it will actually end up until its released. Delays and other problems have popped up that have caused release of the technology to be pushed back. Hopefully, by the end of 2007 or beginning of 2008, consumers will be able to take advantage of the latest developments in flat panel display and take home a SED TV. Prices are being estimated at anywhere from $5000 upwards for the larger displays.