Toshiba's filter will limit the viewing angle on flat-panel displays.

Martyn Williams, IDG News Service

Toshiba has developed a technology that allows users of devices with LCDs to adjust the viewing angle so that its harder for people to view the screen from an angle.

A grid of small, black squares will appear over the displayed image on screens fitted with the technology when viewed from the side, says Midori Suzuki, a spokesperson for Toshiba in Tokyo.

The technology works by controlling the alignment of the pixels and requires a filter to be fitted on top of the display screen and a display controller with support for the function. The addition of this electronic controller means users can vary the viewing angle depending on their needs or switch the function off, she says.

Toshiba hopes to begin mass production of display panels featuring the technology in the first half of 2004.

The company has not decided the exact price, but said the technology will add approximately $140 to the price of a 15-inch LCD screen.

Unexpected Angle?

To anyone that has followed the development of LCD technology the new displays may come as a bit of a surprise.

LCD panel makers have collectively pumped millions of dollars into developing displays that can be seen from a wide range of vantage points and many of the latest panels boast viewing angles of up to 170 degrees in both the horizontal and vertical planes.

While wide viewing angles are desirable in applications where more than one person may be viewing the display, such as a television set, in other applications the ability of bystanders to see what is on the screen may be undesirable, says Suzuki.

Such applications include bank automated teller machines, as well as notebook computer and cellular telephone screens where privacy is important in applications such as e-mail, she says.