October 20, 2011

Varifocal Camera

Security cameras utilize two basic lens types based on focusing parameters. These are called fixed lens cameras and varifocal cameras. Fixed lenses have a “fixed” or constant, unchangeable focal length while varifocal lenses have a focal length that can vary. A more familiar term used for electric powered varifocal lenses is a “Zoom” lens; we will concentrate on the varifocal type in the following article.