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Measuring free-form surfaces

PTB-News 2.2022
Especially interesting for

manufacturers of autocollimators

the optical industry

A novel procedure for determining surface topographies includes an interferometer as its core element.

While the interferometer’s tilt is measured by means of the autocollimating telescope (ACT), the interferometer determines the topography.

This interferometer’s tilt is detected while it is moved in a special guideway for measuring the surface under test. A large number of measurements performed using this procedure allows the topography of the surface to be determined – in particular of free-form surfaces that exhibit a strong curvature. A mirror element consisting of several partial mirrors considerably enhances the angular measuring range of the tilt for free-form surfaces without decreasing the accuracy of interferometric measurements. (Technology Offer 509)


capable of measuring free-form surfaces

considerably enhanced measuring range

compatible with conventional autocollimators

Contact person for questions about technology transfer

Andreas Barthel, Phone: +49 531 592-8307, Opens local program for sending emailandreas.barthel(at)ptb.de, Opens internal link in current windowwww.technologietransfer.ptb.de/en