Surface conduction electron emitter display

SED prototype front view

SED prototype side view

Surface- conduction electron emitter display ( English surface-conduction electron-emitter display , about surface-conducting electron emitter screen ; SED ) refers to a screen technology related to the field emission screen (FED) made of conductive electron emitters.

It was originally developed by Canon and Toshiba in the joint venture SED Inc. , but on January 29, 2007 Toshiba sold its 50% stake in SED Inc. to Canon due to patent disputes with Nano-Proprietary Inc.

As a result of this patent litigation, Canon's marketing of SED-based screens was postponed indefinitely in mid-2007. At the end of May 2010 Canon put the development of SED televisions for home use completely on hold.

functionality

The display works in a similar way to a cathode ray tube . But instead of a single electron emitter , an SED works with one emitter for each subpixel .

An electron emitter has a planar structure and an emitter area consisting of an ultra-thin layer of palladium oxide (PdO), an electrode layer and a glass substrate. The palladium oxide layer has a slit a few nanometers wide. If the electrodes are energized, a tunnel effect occurs in this tiny slit . This then emits electrons, which are accelerated in the electric field of an externally applied high voltage and shot onto an opposing phosphor-coated glass substrate.

In contrast to picture tubes, SED technology works without electron beam deflection. This means that large displays are also suitable for wall mounting.

Launch

The original plan was to start production of 55-inch displays using SED technology in July 2007 on the conventional production facility in Hiratsuka City .

In 2008, Canon and Toshiba wanted to bring the new technology to the mass market in Japan and the USA, but this failed due to patent disputes. Canon has now won this dispute against Applied Nanotech , so that corresponding products can now be sold. Due to the OLED televisions, which have meanwhile also become marketable, however, another technology has meanwhile established itself which now represents additional competition for the market introduction of SED technology.

particularities

The efficiency of the SE display should be over 5 lumens per watt and thus be significantly higher than the 1 to 2 lumens per watt of plasma screens . Compared with LCD displays is to consist of 30 percent according to the manufacturer an advantage. This results in a significantly lower power consumption: Compared to an LCD, an SED only needs half the power and compared to a cathode ray tube only a third of the power.

The achievable contrast of SED is also higher, around 100,000: 1. This results mainly from the elimination of backlighting, as is necessary with LC displays. As with plasma screens, the black is displayed as real black.

Another advantage compared to current flat screens is the very fast response time (less than a millisecond) - similar to classic tube monitors. The manufacturers also point out greater color fidelity and larger viewing angles.

An SED almost exclusively combines the advantages of the two technologies CRT and LCD : low power consumption, high contrast, fast response time, deep black and flat design. Disadvantages that the SED shares with other flat screens are the support of only a single resolution and the possibility of pixel errors appearing as well as the need to introduce a completely new manufacturing technique. As with all screen technologies in which phosphorus-containing phosphors are used, there is also at SE displays the risk of burn-in static images. In addition, as with all cathode ray screens, X- rays are emitted . This does not exist with LCD and plasma screens.

See also

• cathode ray tube
• Laser TV
• OLED
• Plasma screen
• Quantum Dot Display (QDLED)
• Field Emission Screen (FED)

Web links

• SEDTV information platform
• TV with SED technology at the earliest in early 2008
• SED TV Reviews (Engl.)
• Canon puts SED technology development on hold

swell

1. ↑ Canon buys Toshiba's stake in the SED joint venture : wikinews.de, January 15, 2007
2. ↑ https://www.computerbase.de/2007-05/canon-verschreiben-sed-tvs-auf-unbestte-zeit/  : SED postponed indefinitely
3. ↑ http://www.rp-online.de/wirtschaft/news/boerse/Boerse-in-Tokio-mit-Verlusten_aid_861153.html  ( page no longer available , search in web archives )  Info: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice.  : Canon puts SED development on hold  
4. ↑ INPHO 1–2 / 2009 (trade magazine), page 9 Canon: Are the SED televisions coming now?