By Terry Kovarik
The on-going removal of historic Fresnel lenses from all Great Lakes Lighthouses, like those in Kewaunee and Algoma, is an effort to save the lenses from deterioration. Fresnel lens technology originated in the early 19th century and many of the original Great Lakes lighthouse lenses date back to the later part of that century. U.S. Coast Guard Environmental Engineer Wayne Kean says while Fresnel lenses were built solid they can break down and have become harder to maintain.
Kean says with the development of LED technology newer lighthouse beacons can send out brighter light over similar distances to Fresnel lights.