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NPL and UKRI investment for innovation in time resilience, dissemination and application.
Funding of up to £4.7 million available through joint initiative, call for applications now open.

Dimensional measurements

Opthalmic lens calibration service

Enabling accurate production of contact and spectacle lenses

Opthalmic lens

Calibrations are performed for both weak reference lenses as used with eye protection equipment, and stronger reference lenses used for eyesight correction.

Others types of lenses used within instruments and optical systems can also be calibrated, giving both back vertex and effective focal lengths at different monochromatic wavelengths.

Features of our measurements include:

Opthalmic lens

  • Support to the ophthalmic industry
  • Calibration of spherical test lenses up to ± 25 dioptres
  • Traceability to the national unit of length
  • Best measurement capability of 0.002 dioptres
  • Radius, sphericity and flatness measurements of front and back test surfaces
  • Verification of ‘nominal back vertex power’ to meet EN ISO 9342‑1&2:2005 Optics and optical instruments
  • Power measurements of cylindrical and prismatic lenses
  • Supply of calibrated test lenses
  • Non-bespoke lens calibrations
  • 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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Work with us

Our research and measurement solutions support innovation and product development. We work with companies to deliver business advantage and commercial success.
Contact our Customer Services team on +44 20 8943 7070