Title: double-focusing mass spectrograph
Long Title: IUPAC Gold Book - double-focusing mass spectrograph
DOI: 10.1351/goldbook.D01844
Status: current

Definition
An instrument which uses both direction and velocity focusing, and therefore an ion beam initially diverging in direction and containing ions of different kinetic energies is separated into beams according to the quotient mass/charge, these beams being focused on to a photographic plate or film.

Related Term
- film: https://goldbook.iupac.org//terms/view/F02366

Source
- PAC, 1991, 63, 1541. 'Recommendations for nomenclature and symbolism for mass spectroscopy (including an appendix of terms used in vacuum technology). (Recommendations 1991)' on page 1545 (https://doi.org/10.1351/pac199163101541)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/D01844/html
- json: https://goldbook.iupac.org/terms/view/D01844/json
- xml: https://goldbook.iupac.org/terms/view/D01844/xml

Citation: Citation: 'double-focusing mass spectrograph' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.D01844
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Accessed: 2026-07-24T19:15:12+00:00