Super Spherotronic® HR

SuperSpherotronic® HR is an automatic three-ball contacting spherometer designed to meet the highest test plate calibration requirements.

SuperSpherotronic® HR can measure the radius of curvature to an accuracy of 0.01%.

Key Features

  • The mainframe components locating the probe are made of massive stainless steel, hardened and fine ground on machine tools to the highest achievable accuracy.
  • Concentricity of mainframe components to the probe is less than 1 micron (0.00004”).
  • The spherometer rings  are one of the key components of the Super-Spherotronic® HR including an incredible amount of work to eliminate any possible error source.
  • Each ring is delivered with a calibration certificate. The measuring accuracy is directly traceable to NIST standards.
  • The supporting balls are also concentrically positioned with an extreme accuracy of less than 1 micron (0.00004“), ensuring excellent repeatability.
  • To avoid any thermal and mechanical deformation, the supporting balls are made of tungsten carbide (an extremely hard metal), while the probe center is an ultra precise ruby ball.

This completely eliminates any errors introduced by metallic probe centers used in
other spherometers.


  • Calibration of master test plates
  • Concave/convex optical parts
  • Ground or polished optical parts
  • Spheres and balls