Making Eyeglasses That Let Wearers Change Focus on the Fly

[steven johnson]

Cool. No further need for bifocals or trifocals if you're willing to fork over $895.

The idea of a fluid lens whose focal plane can be mechanically adjusted goes back at least to an 1866 patent awarded D. A. Woodward, a Baltimore inventor. Since then there have been a variety of attempts to commercialize the technology, but none have met all the criteria for success. The lens must be thin, light, durable and easily adjustable. Several years ago Dr. Kurtin had his epiphany. A magnetically attached removable front lens would make for a compact and durable system.

Several international efforts are under way to adapt both fluid lenses and the Alvarez approach to the 1.3 billion people at the bottom of the economic pyramid that the World Health Organization estimates as having no access to eyeglasses. Both the Center for Vision in the Developing World in Oxford, England, and U-Specs in Amsterdam are working on glasses that can be distributed at a fraction of the price that glasses cost in the developed world.

The TruFocals eyeglasses, which sell for $895, are the first to become commercially available in the United States. The glasses consist of a lens that is comparable in thickness to that of commercial eyeglasses, but which has three components: a back glass, a fluid-filled inner membrane that is essentially a piece of plastic-wrap-like material stretched across a ring whose surface curvature can be altered mechanically, and an outer prescription lens attached with magnets to the eyeglass frame. To change the focus, the user moves the slider on the bridge.

In principle, that will make the technology accessible to many frames and fashions. The goal is a system that will automatically determine focus by using an accelerometer, a sensor that measures changes in motion, said Ronald Bloom, the company founder. It would need recharging every two or three days. The company has not given out details or pricing of its technology, but has said that it is in user trials.



http://www.nytimes.com/2009/08/04/science/04prof.html?ref=health

[Nictuku]

1. I want a pair!!

I hope it is a successful product and prices come down.

[Why Syzygy]

2. I would definitely be a prospect.

I have two pairs of bifocals; one for the computer and close up and another for driving and long distances. In the grocery store, I have to keep both of them handy; one to find the aisle and the other to look at what's on the shelves. 8*|