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Herriott cell with enhanced sensitivity

PTBnews 3.2018
Especially interesting for

chemical analyses (environmental analysis; industrial safety engineering)

spectral broadband measurement procedures (FTIR spectroscopy)

Beispielhafter Strahlenverlauf: oben mit vier Reflexionen pro Spiegel, darunter in der neuen Herriott-Zelle mit dreifach erhöhter Anzahl an Reflektionen (12 Reflexionspunkte pro Spiegel)

Tiny amounts of certain gases can have considerable effects on human health, the environment and industrial processes. It is now possible to detect such gas quantities with enhanced sensitivity resolution by means of a Herriott cell developed at PTB. Plane mirrors inside the cell make it more effective, allowing the optical path length to be increased by more than one order of magnitude at an equal volume of the cell, which also improves the detection limit. For instance, with a mirror radius of 7 cm and a distance of 1 m between the mirrors, it is possible to achieve an effective optical path length of more than a kilometer (instead of 100 m until recently). (Technology Offer 397)


increases the optical path of the laser/light beam

considerably improves the detection limit

can be used for broader spectral ranges

in contrast to techniques such as mass spectrometry, the sample material is not influenced (non-invasive method)

Contact person for questions about technology transfer

Andreas Barthel,
Phone: (0531) 592-8307,
Opens window for sending emailandreas.barthel(at)ptb.de,
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