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Far and Extreme Ultraviolet Detector Calibrations


Transfer standard photodiodes may be purchased with a calibration in the range from 5 nm to 254 nm. Other detectors supplied by the customer may be calibrated if they are suitable for use as transfer standards in this spectral region.


The Ultraviolet Radiation Group maintains the scale of detector responsivity in the far and extreme ultraviolet spectral regions. This scale is realized by calibration of working standard photodiodes against a primary standard detector, either a cryogenic radiometer or ionization chamber, depending on the wavelength. These working standard photodiodes are kept as the basis for disseminating the scale to the scientific community.

Transfer standard photodiodes are calibrated by comparison to the working standard detectors at one of two facilities at NIST. In the far ultraviolet (FUV) region - sometimes called the deep ultraviolet region (DUV) - from 50 nm to 254 nm, calibrations are performed at the FUV Calibration Facility. In the extreme ultraviolet (EUV) from 5 nm to 50 nm, calibrations are performed at the EUV Detector Radiometry Beamline (BL-9) at SURF III.

Once calibrated, transfer standards are sent to the customer for use in their laboratory as standard detectors. In this way, the detector responsivity scale maintained at NIST is available to calibrate detectors used in scientific research and development in other laboratories. Customers include researchers at universities, companies, and government laboratories around the world. NIST-calibrated transfer standard detectors are used in many fields of research including solar monitoring, lithography, plasma diagnostics, astronomy, and water disinfection.

Additional Technical Details:

To obtain a transfer standard photodiode, please contact the NIST staff identified on this page (see the Staff and Contact sections). Generally, orders can be accepted by purchase order or credit card. Note that it is NIST policy that orders placed from outside the United States be prepaid by credit card, bank wire transfer, check, or other means. Customs duties are the responsibility of the customer.

Information on the detectors and current fees is available on the
VUV Detector Calibrations web pages.

Mounting detectors on beamline 9.

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Related Programs and Projects:

Far and Extreme Ultraviolet Radiometric Scale Realization
SOHO/SEM Calibration
SDO/EVE/ESP Calibration

Associated Products:


General Information:
301-975-3992 Telephone

100 Bureau Drive, MS 8411
Gaithersburg, MD 20899-8411