One maxim about investing in the tech sector is that popular products this year may be obsolete next year. Recognizing the trends in technology can provide investors with enormous gains, especially if they can identify the new technology well before the market gets wind of it.A case in point: flat-panel display technology that outperforms liquid-crystal display (LCD) and plasma. The new technology is called organic light emitting diodes (OLEDs) and it's currently being tested by Samsung and Toshiba. While still in early development, OLED technology is impressive, with the screens coming in thinner than anything currently on the market and requiring much less energy to operate. No one knows for sure just how expensive these televisions are going to be when they are mass-marketed down the road, or even how far we are from seeing these OLED televisions show up in stores. But if the market for OLED television turns out to be even half of the flat-panel display market's $50 billion in sales in 2005, it could be quite profitable for early market entrants. To get in early on the OLED trend, we ran a screen for publicly traded companies involved in the design of OLEDs and came up with two low-dollar names that speculative investors should keep an eye on: Cambridge Display ( OLED) and Universal Display ( PANL). We aren't taking action for the Stocks Under $10 model portfolio because we already own two stocks with exposure to the television industry, and we want to remain diversified. Based in the U.K., Cambridge is the smaller of the two companies, with only a $150 million market capitalization and shares recently trading at $6.53. But its OLED screens, based on polymer OLEDs, or P-OLED's, are already making an impressive showing based on recently announced joint ventures. The company recently signed a joint venture with Japanese industrial giant Sumitomo to form a company to develop its OLED materials into commercial display and lighting applications in Japan. And the company has a deal with IBM (IBM:Nasdaq) to market IBM's flat-panel display backplanes that are used in larger LCD displays already.