John Richard Wiegand discovered the Wiegand effect, a physical phenomenon in which a special wire, called a "Wiegand wire", can detect small magnetic fields.
The Wiegand interface is a de facto wiring standard which arose from the popularity of Wiegand effect card readers in the 1980s.
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The sensor in such a system is often a "Wiegand wire", based on the Wiegand effect, discovered by John R. Wiegand.