page_title: Lighthouse
section_title: Laser light
hierarchical_section_title: Lighthouse / Technology / Laser light
caption_attribution_description: English: Lighthouse at Point Danger, Coolangatta, Queensland — a memorial to Lieutenant James Cook of HM Bark Endeavour who named the Point and described the area during the voyage of 1770. Nederlands: Vuurtoren bij Point Danger.
context_page_description: A lighthouse is a tower, building, or another type of structure designed to emit light from a system of lamps and lenses and to serve as a navigational aid for maritime pilots at sea or on inland waterways.
  Lighthouses mark dangerous coastlines, hazardous shoals, reefs, rocks, and safe entries to harbors; they also assist in aerial navigation. Once widely used, the number of operational lighthouses has declined due to the expense of maintenance and has become uneconomical since the advent of cheaper and often much more effective electronic navigational systems.
context_section_description: Experimental installations of laser lights, either at high power to provide a "line of light" in the sky or, utilising low power, aimed towards mariners have identified problems of increased complexity in installation and maintenance, and high power requirements. The first practical installation, in 1971 at Point Danger lighthouse, Queensland, was replaced by a conventional light after four years because the beam was too narrow to be seen easily.
caption: Point Danger lighthouse, Queensland, 1971
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