Intel is showing off a prototype laptop this week that has four screens, increasing the display area so that multiple applications can be viewed simultaneously.

The laptop has a primary LCD screen in the usual position and three small OLED (organic light-emitting diode) touch screens just above the keyboard. Code-named Tangent Bay, the system is being shown at the Intel Developer Forum in San Francisco.

The prototype on display here isn't particularly stylish-looking, but the extra screens might add some convenience. In a demonstration, they were used to display a music playlist, a photo album and a calculator, which could all be operated via the touch screens while running a different application on the main screen.

Tangent Bay pushes the limits on the number of screens available on laptops. Companies including Lenovo have released two-screen laptops, with an auxiliary display that slides out behind the main LCD screen.

Intel is showing the prototype in the hope that systems builders will pick up the design and offer a commercial product. The division of Intel that builds these prototypes earlier came up with the small mobile Internet devices, or MIDs, which were offered by some companies.

Intel Marketing Manager Renuka Awasthi, offering another example of how a four-screen system might be useful, said a person scouring the Web for a vacation deal could launch a calculator, weather site and chat session on the other screens.

"There's no limitation to the applications you can run on the auxiliary screens," according to Awasthi. "People value additional display real estate."

Certain tasks lend themselves to the small screens, such as writing Twitter messages or updating a Facebook page. Users can drag and drop applications between the screens to change what's displayed.

Intel came up with the design after a study showed that some laptop users have 20 to 30 applications running at once, making it difficult to sort through them and find information.

Some people also like using widgets, small programs that sit on the desktop to display information, but other applications can obscure the widgets if they are all on the same screen, Awasthi said.

The four-screen laptop used a standard-voltage Intel Core 2 CPU and integrated Intel graphics, though Intel representatives declined to provide further hardware details.