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?
Hans Christian Andersen
Back in the day
Signed by Canada, Mexico, and the US, NAFTA created the world's largest free-trade area. The agreement immediately lifted tariffs on the majority of goods produced by the signatory nations, and it called for the gradual elimination of most of the remaining barriers to cross-border investment and to the movement of goods and services among the three countries. Critics claim that NAFTA has led to job loss in the US due to the prevalence of maquiladoras, which are what?
Born on a day like today
Stieglitz was the first art photographer in the US. More than any other American, he compelled the recognition of photography as a fine art. After editing a series of photography magazines, he established the famous gallery "291" in New York City. The gallery soon broadened its scope from fine-art photography and introduced to the US works by members of the modern French art movement, including Cézanne and Picasso. It also exhibited the works of what American artist whom Stieglitz later married?