It is a problem that vexed Edwin Land, the inventor and founder of Polaroid: How can the sometimes dangerously blinding glare of headlights from an oncoming automobile be eliminated?
Land devised an elegant solution in which drivers wore glasses that polarized light one way while the light from headlights was polarized the other way."It blocked the glare of the headlight, but the problem was it also blocked all the rest of the light, so you couldn't see," said Sadeg M. Faris, an inventor in Hawthorne, N.Y., who holds dozens of patents related to super-con-ducting electronics and other areas. Faris said he had found a better solution, for which he has received a patent.
His invention uses a liquid-crystal screen hinged to the visor on the driver's side, a small video camera hanging just below the rearview mirror and an infrared sensor at the back of the camera that is aimed at the driver.
The video camera, trained on the road and aided by the infrared sensor, which informs it of the position of the driver's eyes, would electronically tell the liquid crystal to act as a filter by darkening individual pixels - minuscule dots of color - at the point where the headlights hit the windshield, according to Faris.
"This is a very dynamic situation," Faris said. "As the car moves and your head moves, the pixels adjust accordingly."
Faris said that his company, Reveo Inc., had not assembled a prototype but that he thought such a product would retail for about $400.
"It may sound complicated, but the ingredients are pretty simple," he said. He received patent 5,305,012.
- Teresa Riordan