Editing Metal detector (section)

=== Technology development ===

====Gerhard Fischer====

[[Gerhard Fischer (inventor)|Gerhard Fischer]] developed a portable metal detector in 1925. His model was first marketed commercially in 1931; he was responsible for the first large-scale hand-held metal detector development.

Gerhard Fisher studied [[electronics]] at the [[TU Dresden|University of Dresden]] before emigrating to the United States. When working as a research engineer in [[Los Angeles]], he came up with the concept of a portable metal detector while working with [[Aircraft Radio Corporation|aircraft radio]] detection finders. Fisher shared the concept with [[Albert Einstein]], who foresaw the widespread use of hand-held metal detectors.

Fisher, the founder of Fisher Research Laboratory, was contracted by the [[Federal Telegraph Company|Federal Telegraph]] Company and Western Air Express to establish airborne direction finding equipment in the late 1920s. He received some of the first patents in the area of radio-based airborne direction finding. He came across some unusual errors in the course of his work; once he figured out what was wrong, he had the foresight to apply the solution to a totally unrelated area, metal and mineral detection."

Fisher received the patent for the first portable electronic metal detector in 1925. In 1931, he marketed his first Fisher device to the general public, and he established a famous Fisher Labs company that started to manufacture and develop hand-held metal detectors and sell it commercially.<ref>{{Cite web|title=The History of the Metal Detector {{!}} MetalDetector.com|url=https://www.metaldetector.com/learn/metal-detector-history/history-of-the-metal-detector|access-date=10 May 2021|website=www.metaldetector.com}}</ref>

====Charles Garrett====

Despite the fact that Fisher was the first to receive a patent for an electronic metal detector, he was only one of many who improved and mastered the device. Charles Garrett, the founder of Garrett Metal Detectors, was another key figure in the creation of today's metal detectors.

Garrett, an [[Electrical engineering|electrical engineer]] by profession, began metal detecting as a pastime in the early 1960s. He tried a number of machines on the market but couldn't find one that could do what he needed. As a result, he started developing his own metal detector. He was able to develop a system that removed oscillator drift, as well as many special search coils that he patented, both of which effectively revolutionized metal detector design at the time.

==== To present day ====

In the 1960s, the first industrial metal detectors were produced, and they were widely used for mineral prospecting and other [[industry (manufacturing)|industrial]] purposes. De-mining (the detection of [[Land mine|landmines]]), the detection of [[weapon]]s such as [[Knife|knives]] and [[gun]]s (particularly in [[airport security]]), [[Geophysics|geophysical]] prospecting, [[archaeology]], and [[treasure hunting]] are just some of the applications.

Metal detectors are also used to detect foreign bodies in food, as well as steel reinforcement bars in concrete and pipes. The building industry uses them to find wires buried in walls or floors.