Editing Searchlight (section)

{{Short description|Intense focused beam lamp for improving visual detection}}
{{Other uses|Searchlight (disambiguation)}}

[[File:The Auxiliary Territorial Service in the United Kingdom 1939 - 1945 H36315.jpg|thumb|[[Auxiliary Territorial Service|ATS]] officers-in-training crew a 90 cm searchlight in Western Command, 1944]]

A '''searchlight''' (or '''spotlight''') is an apparatus that combines an extremely [[luminosity|bright]] source (traditionally a [[carbon arc lamp]]) with a mirrored [[parabolic reflector]] to project a powerful beam of [[light]] of approximately parallel rays in a particular direction. It is usually constructed so that it can be swiveled about. The most common element used in modern searchlights is [[Xenon|Xenon (Xe)]].<ref>{{cite journal |last=Rehmet |first=M. |year=1980 |title=Xenon lamps |journal=IEE Proceedings A - Physical Science, Measurement and Instrumentation, Management and Education, Reviews |volume=127 |issue=3 |pages=190–195 |doi=10.1049/ip-a-1.1980.0030 |issn=0143-702X}}</ref> However, [[Rare-earth elements]] such as [[lanthanum|lanthanum (La)]] and [[cerium|cerium (Ce)]] are used in [[phosphors]] to improve light quality in some specialized searchlights.<ref>{{cite web |url=https://www.stanfordmaterials.com/blog/lanthanide.html |title=What Are the Lanthanide Series? |last=Lowen |first=Eric |website=Stanford Advanced Materials |access-date=Sep 9, 2024}}</ref>