Zoom lens in camera phones|
The digital zooms now used in camera phones only enlarge part of a picture without enhancing its quality, giving sometimes disappointing results. Other than its size, the greatest advantage of the lens invented by the two Université Laval researchers is that it allows for the movement of the focal point - as with a real camera - thus increasing the clarity, detail, and overall quality of an enlarged picture. Such a technology could help boost a market that seems to be losing its snap.
How is the opto-electrical zoom lens made?
According to a recent market study by one of the major camera makers, a significant number of camera phone owners find their devices less than satisfying, mentioning among other problems the poor picture quality. The new lens is made by adding a small quantity of photosensitive material to a liquid crystal cell. When the material is exposed to laser light, it forms a network of stable polymers varying in density according to the intensity of exposure. "The network is like a spiderweb, with its center denser than its periphery," explains Galstian. "When we apply a weak electrical current to it, the crystals in the center realign differently from those in the periphery and thus take on the shape and behavior of a lens."
Focal point from 60 centimeters to infinity
The curve of the lens - its focal point - can be modified by changing the intensity and frequency of the electrical current. The researchers have thus been able to modify the lens' focal distance from 1.6 to 8 meters in a few milliseconds by increasing the voltage from 1.5 to 4.5 volts. "The reaction is very fast and doesn’t involve any mobile parts or mechanical movements." The focal point of the lens can go from 60 centimeters to infinity.
In theory, the lens sounds like the best thing to have
Fred Greenslade, a sports and wildlife photographer in Portage la Prairie, Man., is intrigued by the invention: "I'll believe it when I see it but it sounds great. I guess I'd have a few questions. Is it going to work? How fast will it be? What's the quality going to be? "But it sounds, in theory, like the best thing to have."