Fresnel lenses are great as reading aids, magnifiers or for use in DIY projection projects. These lenses are great for reading fine print in books, magazines, menus, maps, telephone directories, etc. Makes a great gift for those who need a visual aid. They can also be used for light duty solar such as heating water and solar furnace projects and more.
NOTE: These are the very high quality kinds, which are thick, yet flexible Fresnel lenses. Therefore if you hold a sheet by one end, the other end won't slumps/bend over on its own, as is the case with the cheap flimsy kinds.