In a small meeting room at the edge of the show floor at the Consumer Electronics Show, a startup company is demonstrating a motion sensing interface technology that could offer a radical new way for interacting with games, PCs and televisions.

The technology, from Israeli startup PrimeSense, can be embedded in TVs, Blu-ray players and set-top boxes, allowing people to use hand gestures to scroll through cable TV menus from their living room couch, or stand in front of the TV and shuffle documents on the screen by moving their hands around in mid-air, much as Tom Cruise does in the sci-fi film "Minority Report."

The technology can also be used as an interface for PC games and game consoles. In that way resembles Microsoft's Project Natal, which allows users to stand in front of a large screen and use full-body gestures, such as a kick, punch or jump, to control an avatar on the screen. Microsoft said this week that it will launch Project Natal for Xbox 360 users later this year.

PrimeSense's system uses a sensor-camera that sits above the screen and projects a beam of light, at a wavelength close to infrared, to build a 3D map of the people and objects in a room. When a person activates the device by thrusting their palm out towards the screen, the system locks onto that person and puts them in control.

PrimeSense is a fabless chip company, which means it designs the 3D sensor chip that powers the technology, as well as software that gets embedded into devices. It says it has an agreement with a large manufacturer to produce its chips for the mass market, although it won't yet say who it is.

In fact, a big question mark over PrimeSense is that it won't disclose any of its customers publically yet, although companies in the PC and set-top box markets are likely to announce products this quarter that include its technology, according to Adi Berenson, PrimeSense's vice president for business development and marketing. The company is also in talks with TV makers, he said.

A prototype system is being shown behind closed doors to reporters and industry partners at CES this week. The technology sounds futuristic, but in fact variations on it have been in the works for years, and are also being developed by competitors including Canesta, Optrima, PMDTechnologies, and Mesa Imaging of Switzerland.

Most companies in the market are using a "time of flight" technology, which works by emitting an infrared pulse from a camera above the screen and measuring the time it takes to bounce back from objects in the room. This allows the systems to calculate the distance of each surface and create a virtual 3D model of the room. Any changes, like hand movements, are then translated onto the screen.

PrimeSense uses a variation of this. Instead of calculating the time for light to bounce off of objects, it encodes patterns in the light and builds a 3D image by examining the distortion created in those patterns by objects in the room, Berenson said.

The entire system, including the sensor chip and middleware, will cost manufacturers $20 to $30 to add to PCs or TVs when shipped in volume, Berenson said. Most high-end TVs will have enough computational power to run the software, and have USB 2.0 ports where the sensor device can be plugged in, he said.