Surface metrology

Single-shot surface qualification

When integrated in a reflection setup, the Phasics SID4 wavefront sensors can perform surface characterization. Kaleo software outputs the 3D surface map and the radius of curvature of convex or concave surfaces, such as lenses, mirrors, or molds. All surface quality parameters defined by the ISO 10110 standard such as surface irregularities, roughness, and waviness are calculated from this measurement. Surface profiles can also be extracted in any direction and results can be compared to the theoretical surface.

• ▽ Flat and slow surface measurement setup

  

  In order to perform surface measurement, the beam is expanded to be adjusted to the size of the area of interest. The surface under test is imaged onto the SID4 wavefront sensor. First, a reference measurement is performed with a reference flat and the test sample  is aligned and measured. The measured wavefront is twice the topography of the test surface.

• ▽ Concave surface measurement setup

  

  For concave surface measurement, a condenser is added to the optical setup in order to illuminate the surface under test with the right numerical aperture.                                                                                     

• ▽ Convex surface measurement setup

  

  The same approach with a condenser is used to qualify convex surfaces.