TV innovation starved of cash

Chris Forrester

LCD and Plasma TV sets still rule the retail sector, while rear-projection units have all but disappeared even in North America, says this quarter’s EBU Technical Report. A study by BBC R&D’s Richard Salmon suggests that it is now cash that is stifling development of ‘next generation’ TV sets.

Mr Salmon says that with some of the (once) major names in Plasma technology (Pioneer, NEC, Fujitsu and Hitachi) having quit the manufacturing side of the Plasma industry, only Japan’s Panasonic remains interested in Plasma production. “However, Panasonic has made the investment required to bring the next generation of Plasma displays to the market, and the NeoPDP results in a big cut in power consumption, and thinner and lighter panels, all increasingly important factors,” says Salmon.

LCD manufacturers are also making investments in power-light models, as well as so-called ultra-thin units, increasingly important to buyers. But retail profit margins are just as thin, and competition tough. Which, says Salmon, means new R&D is being starved. He suggests that Thick-film Dielectric Electro-Luminescent (TDEL) technology looked very promising five years ago, “with an impressive 34-inch full-colour prototype on show from iFire 3. Capital investment was however not forthcoming to set up the planned pilot manufacturing plant but, towards the end of 2008, the iFire technology was sold by Westaim to a Canadian-Chinese joint venture, CTS Group. Further developments are now awaited.”

“Surface-conduction Electron-emitter Display (SED) technology also looked very promising until two years ago but patent/licensing problems caused the suspension of the Canon-Toshiba joint venture, and a loss of impetus. The legal wrangles are apparently now solved (in December 2008). Applied Nanotech announced that they would not be appealing against the court decision that ruled in favour of Canon in July 2008, but the opportunity to go into production has been lost and we wait to see whether this technology will eventually be able to fulfill its evident potential,” he adds.

Mr Salmon examines a couple of other ‘new technologies’ worth watching out for, not least FED and OLED. “The last couple of years have seen a resurgence of interest in Field Emission Displays (FEDs) – similar in many ways to SEDs in that electrons are accelerated across a small gap to emit light from a phosphor. In particular, electron emission from Spindt tips has come to the fore again (FED has its origins in 1958, with Spindt emission dating from 1968, so maybe this does not really qualify as “new technology”!). FET Inc, a spin-off from Sony, was set to purchase Pioneer’s old plasma display factory earlier this year, but lack of financial backing caused this development to be abandoned in March 2009. This is very disappointing, since Ikegami had demonstrated a very promising prototype monitor based on a prototype FET Inc panel.”

“Although Samsung has demonstrated a 40-inch Organic Light-Emitting Device (OLED) display, and has hinted at a 50-inch version this year, the company does not expect OLED to become a mainstream product for 4-5 years. The major problem is how to create the larger screen sizes needed for TV. Because OLED is an emissive technology, the electrical current required to generate the light has to be supplied via the active matrix backplane technology. (In an LCD, the main power dissipation is in the backlight, not in the display matrix.) LTPS (low temperature poly silicon) is therefore the usual backplane technology, but is limited in the substrate sizes achievable to twenty-something inches, and larger displays have typically been made by “tiling” several panels together. However, OLED displays have recently been demonstrated on amorphous-silicon / microcrystalline-silicon backplanes. OLED panels are impressive and attractive, but are still some way from making a major impact in the TV market. OLED technology appears the most likely challenger for the future, but is unlikely to seriously challenge LCD for some 5 or even 10 years to come.”