A stroll rounds the halls of last week's IFA electronics show in Berlin, or this week's CEDIA show in Denver or, well, just about any consumer electronics show in the last year makes it clear that thinness is the latest battleground in the competitive flat-panel TV business.

But with so many new models and prototypes appearing all the time it can get confusing keeping up with who's in the lead and where technology is going so here's a brief round-up of the current state of play.

Thinnest available TV

When it comes to thinness no-one has been able to beat Sony's XEL-1. The set is based on OLED (organic light emitting diode) screen technology and is just 3 millimeters thick.

OLED is an emerging flat-panel display technology that uses an organic material in the pixels that emits its own light, so a backlight -- one of the things that adds to the thickness of LCD (liquid crystal display) sets -- isn't needed. That means OLEDs are thinner and use less power. OLED screens also handle fast-moving images better and offer richer color reproduction than current LCDs (liquid crystal displays) and PDPs (plasma display panels).

The great pictures have attracted crowds at recent shows leaving no doubt that consumers are interested in the brilliant pictures and thin bodies but as with any new technology there's a price to pay and in the case of the XEL-1 it's US$2,000 -- for an 11-inch TV.

That hasn't stopped wealthy customers snapping them up but they remain out of the reach of most consumers.

The XEL-1 first went on sale in Japan in late 2007 and followed in the U.S. in January 2008. At IFA Sony announced the European launch of the set.

Right now the XEL-1 is the only OLED TV on the market but Sony has promised a 27-inch model within the next nine months and Samsung has been showing prototypes of 14- and 31-inch OLED TVs but has yet to announce commercialization plans.

Ever-shrinking LCD TVs

In the LCD TV market all of the focus has been on making thinner backlights to slim down the size of TVs. At the beginning of the year Sharp was making headlines with a set that was just 34mm thick and trumped that at IFA with its new XS1-series sets that measure 23mm at their thinnest point.

But due to a fate of scheduling the company had lost the thinnest-TV crown before it even unveiled the XS1 sets. A couple of hours earlier Sony presented its ZX-1 TV that is just 9.9mm thick.

The IDG News Service is a Network World affiliate.