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Measuring device for ultraprecise spheres

PTB-News 2.2020
Especially interesting for

sphere manufacturers

dimensional metrology

Measuring setup with sensors on a fork-like structure, accommodated at the equator of the sphere.

Nearly perfect spheres are used in various branches of industry, such as optics or industrial metrology. Conventional procedures to measure form error are, however, much too slow and tedious for the industrial manufacturing of such spheres. A new measuring device developed by PTB is reliable and more economical than existing systems and provides fast results. This device consists of two collinear interferometers for length determination. These interferometers measure a sphere from two positions that are located exactly opposite each other. Rotating the sphere allows its diameter profile to be determined at the equator, and form errors in the lower nanometer range to be detected. (Technology Offer 447)


simple and affordable setup

intrinsic compensation of kinematic errors

fast measurement data acquisition

Contact person for questions about technology transfer

Andreas Barthel,
Phone: +49 531 592-8307,
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