Article of the Day:
Fresnel Lens
A Fresnel lens is a thin optical lens that has the properties of much thicker and heavier lenses. It consists of concentric rings of segmental lenses that bend and magnify light rays, creating a single, concentrated beam of light. This design allows the lens to capture more oblique light from a light source than conventional lenses, making its beam visible across greater distances. The light from the first Fresnel lens, placed in a lighthouse in 1823, could be seen from how far away? More…: https://play.google.com/store/apps/details?id=com.tfd.mobile.TfdSearch
euzicasa 