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Dimensional measurements

Radius of curvature and sphericity calibration service

Measurements that are directly traceable to national standards

Radius of Curvature

The departure of the surface under test from a best fitting spherical surface, presentable by graphical illustrations, provide a valuable assurance of the quality of a manufactured spherical surface, detecting both aspherical anomalies and astigmatism, and enabling accurate production of items such as isometric reference lenses.

Pre-booked calibrations can be carried out with a quick and reliable turnaround enabling customers to return to their high quality services without delay. Short notice bookings are also taken and normally dispatched quickly. Majority of calibrations are completed within 1 to 2 weeks.

Radius of Curvature

  • Measurement of radius gauges traceable to national standards
  • Certified range for radius of curvature (ROC) from 5 mm to 1000 mm
  • Best measurement capability of 0.002 mm ROC and 33 nm departure from sphericity
  • 3D plot of sphericity available
  • Measurements possible on most polished surfaces
  • Non-bespoke radius calibrations (i.e. some surfaces greater than 1000 mm)
  • Technical consultancy and training provided
  • UKAS (ISO 17025) accredited measurement service


Don’t see what you are looking for? Our diverse skill set enables us to provide bespoke solutions. Please contact us to discuss your requirements.

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Contact our Customer Services team on +44 20 8943 7070