Geiger counter
instrument used for measuring ionizing radiation
A Geiger counter (, GY-gər; also known as a Geiger–Müller counter or G-M counter) is an electronic instrument for detecting and measuring ionizing radiation with the use of a Geiger–Müller tube. It is widely used in applications such as radiation dosimetry, radiological protection, experimental physics and the nuclear industry.
It detects ionizing radiation such as alpha particles, beta particles, and gamma rays using the ionization effect produced in a Geiger–Müller tube, which gives its name to the instrument.
In wide and prominent use as a hand-held radiation survey instrument, the Geiger counter is perhaps one of the world's best-known radiation detection instruments. As such, the phrase Geiger counter is often used generically to refer to any form of dosimeter (or, radiation-measuring device), but scientifically, a Geiger counter is only one specific type of dosimeter.
The original detection principle was realized in 1908 at the University of Manchester, but it was not until the development of the Geiger–Müller tube in 1928 that the Geiger counter could be produced as a practical instrument. Since then, it has been very popular due to its robust sensing element and relatively low cost. However, there are limitations in measuring high radiation rates and the energy of incident radiation.
The Geiger counter is one of the first examples of data sonification.
Principle of operation
A Geiger counter consists of a Geiger–Müller tube (the sensing element which detects the radiation) and the processing electronics, which display the result.
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Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated Aug 11, 2026. The linked authority identifier is Q48171. The Library of Congress control number is sh85053668. None of the 2 selected statements returned an explicit reference. The first chronological checks are 1908 and 1928.
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This entry incorporates text from “Geiger counter” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.