Metrology

We adhere to measuring specifications listed in ISO 10110 and MIL-specs when conducting tests and measurements on our products. We have a wide range of equipment that allows us to measure any form of optical product; be it spherical or a-spherical.

Our general specifications are:

• Form accuracies up to λ/10
• Surface roughness better than 2 nm, depending on the material
• Tolerances in focal length within 0.1%

Metrology equipment:

In our laboratory we have the following equipments at our disposal:

Co-ordinate microscopes

These microscopes have an accuracy of less than 2 microns.

Focimeter and dioptre meter

For verification of our contact lenses we use our focimeter and dioptre meter to confirm the correct mounting, as well as the power of the lens.

Wyko-400 IOL interferometer

The Wyko 400 system is a high-performance digital phase-shifting interferometer.

The testing capabilities of the Wyko 400 are useful for measuring optical-quality surfaces in a precise, non-contact evaluation. The wide variety of parts that can be tested includes mirrors, lenses, flats, spheres, disks, windows, prisms, corner cubes and complete optical assemblies.

The 400 system provides detailed quantitative wavefront information with minimum involvement by the operator. Measurements are based on many tens of thousands of data points rather than on the few hundred that are available with static fringe-following techniques.

Digital phase-shifting

The interferometer takes wavefront data by combining the light reflecting off the product with the light reflecting off a reference surface. When the two beams collide, the light waves interfere to produce a pattern of dark and light bands called fringes.

Talysurf PGI 840

Measures lens profiles and roughness. We use our Talysurf to check the surface of aspherical and toric mirrors, lenses and other non spherical optical components.

Important terms and definitions:

Pv/Rt = Peak-to-valley of the OPD data

Ra = Arithmetic average roughness height over the entire 3D surface

Rq/Rms = Rms average roughness height over the entire 3D surface