Traceable multiple sensor system for measuring curved surface profiles with high accuracy and high lateral resolution

Abstract

A new scanning system is presented for the high-accuracy form measurement of flat and slightly curved surface profiles. The system employs a small measuring head with multiple distance sensors that is scanned along the surface. Additionally, an autocollimator is utilized to account for angular scanning stage errors. For this setup, suitable design of experiment allows scanning stage errors as well as systematic distance sensor offset errors to be eliminated. As a consequence, high-accuracy form measurements of flat and slightly curved surfaces with high resolution can be achieved. A demonstrator setup has been realized and tested. The results confirm the high potential of this method.