How It Works - Zoom Lenses

Posted on Wednesday, June 20 2007 @ 09:03:54 CEST by Thomas De Maesschalck
There are many different designs for zoom lenses, but they all have some basic principals in common. They consist of a number of differently shaped individual lenses or ‘elements’, some of which move relative to one another to alter the magnification of the image without altering the focus.

Check it out at Trustedreviews.