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There are three different methods to perform straightness measurements with the HPI-3D device: Angular, Wollaston and 3D.

  • Used angular method in base straightness measurements (like optical autocollimator);

  • Use the Wollaston method to determine “movement in space” measurements. For example, to characterise the movement of a machine table or working tool;

  • Used 3D method for rapid estimation of “movement in space”. Similarly to Wollaston method but the measurement is HPI-3d performs in the three axes at once.

The main parameters of those methods are described in the Lasertex Technical Data below.

Measurement Range Resolution Accuracy
Straightness measurement (with angular optics) 0 – 15 m 0.01 µm (for 100 mm base) ± 0.2 %
Straightness measurement (with Wollaston optics) 0.3 – 9 m
Vertical range up to ± 30 mm
0.01 µm ± 0.5 % x L µm
Straightness measurement (with 3D optics) 0 – 6 m 0.1 µm ± ( 10 + 10 * L ) µm