Primary Calibration Equipment

What is Primary Calibration?

Equipment which sets the world’s length measurement standards in laboratories undertaking Primary and Legal Metrology work. Here we tell you about how our products relate to "legal metrology".

Gauge Block Interferometer

The GBI300 sets the standard throughout the World in Gage Block Measurement by Interferometry. Over 25 Primary Calibration Laboratories in Europe, North and South America and Asia rely on NPL-Brown & Sharpe Gage Block Interferometers for their Primary Calibration of Gage Blocks.

Length Bar Interferometer

The LBI1.5 was designed by the UK NPL to meet the requirement for calibrating longer type Length Standards at a Primary level and with the best possible Measurement Uncertainty. Long Series Gage Blocks and Length Bars in lengths up to 1.5 meters (60") can be accommodated.

Spectrum Lasers

Spectrum is a range of Frequency Stabilized Lasers offering the user the choice of different laser wavelengths. Users of specialised Interferometry will find Spectrum lasers provide the variety and flexibility they need. Spectrum Lasers are a key element in the Primary level of Calibration afforded by the NPL-B&S Gage Block and Length Bar Interferometers.

GBI Upgrades

In the 1990s the NPL-Tesa Automatic Gauge Block Interferometer (AGI) was the instrument that set much of the World’s measurement standards. Now B&S has introduced the GBI300, an improved version of the GBI resulting from recent developments at NPL. If you have one of the 20 or more NPL-Tesa AGI100 or AGI300 GBI’s you can now get an upgrade to the full GBI300 specification.


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Hexagon Manufacturing Intelligence
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