The system can automatically recover wide-angle views of what people are looking at, including panoramic details to the left, right and even slightly behind them. It can also calculate where people are gazing - for instance, at a single smiling face in a crowd.
The detailed wide-angle information recovered by the new system is possible because the image reflected by the cornea is broader than that captured on the retina. The retinal field of view is considerably less than a hemisphere - 160 degrees horizontally and 130 degrees vertically. But the corneal image is roughly about a hemisphere or more, permitting objects to the side and behind the person to be seen so long as the person is not looking away from the camera at an extreme angle.
The crucial algorithm in the system automatically computes the relative position and orientation of the cornea in relation to the camera, using the elliptical shape of the limbus, or border, between the cornea and the white of the eye. "The shape of the limbus tells you where the eye is in the three-dimensional scene and which direction the eyeball is pointing," Dr. Nayar said. The wide-angle image can then be created from this information.
A new type of pump to help failing hearts will undergo clinical trials in autumn 2004 in the UK. The pump has a curious side effect: people implanted with the device have no pulse.
What makes the VentrAssist different is that it only has one moving part, a spinning impeller that drives a continuous stream of blood. That means the pulse is replaced by a gentle whirling noise that patients describe as similar to the sound of a washing machine. More importantly, the device prevents blood from stagnating, reducing the risk of clotting.
Six copper coils within the device's titanium walls generate magnetic fields that make the magnet-cored impeller blades spin. The blades push blood out to the body while forming a high-pressure, liquid cushion that levitates the impeller and holds it steady.
"There is no predicted lifespan for VentrAssist because there are no wearing parts," says co-inventor of the device and company founder John Woodard. "It could be a hundred years, we don't know."