The NPL Optical Dimensional Standard

NPL provides dimensional measurement facilities and standards for industries requiring accurate measurements using non-contact optical instrumentation. The achievement of measurement repeatability requires proper instrument alignment and measurement procedures to be followed. The use of an appropriate standard enables accuracy to be achieved and the performance of the equipment to be maintained satisfactorily. NPL’s capabilities include measurement of Opthalmic Lenses, Optical Flatness, Radius of Curvature and Sphericity and, the provision of standards for calibrating optical metrology systems, image analysers, vision inspection systems and Vision CMMs.

NPL’s range of calibration standards consists of chromium films on glass plates. They include two-dimensional Grid Plate position standards, a Reference Stage Graticule for use with image analysers in particle sizing, a range of Optical Linescales and Stage Micrometers and the multi-purpose NPL Optical Dimensional Standard, shown above.

• Angle measurement: Autocollimators, polygons, angle gauges and index tables
• Two-Dimensional Grid Plate Standards
• NPL Reference Stage Graticules
• Linescale Standards
• Linewidth Standards
• Optical Dimensional Standard
• Ophthalmic and Spherical Lenses
• Flatness, Radius and Sphericity