This paper describes a desktop, turnkey metrology system tailored for the measurement of the surface topography of small optical components such as contact and intraocular lenses and molds. The system incorporates a wavefront sensor that provides interferometric accuracy while being relatively insensitive to vibration. Highly accurate measurement of the radius of curvature (typically better than .02%, 2 micrometers on a 10 mm radius part) is obtained using a patented data reduction system. The system also measures toroidal and aspherical systems and can be readily adapted to the measurement of longer radius parts. The system is capable of measuring surface topography in less than 10 seconds after part placement and is usually operated by unskilled personnel. Full three-dimensional topography is reported including peak-to-valley and root-mean-square surface departure, and Zernike polynomials. This paper provides an overview of the optical configuration and software algorithms that enable the highly precise capability of the device.

Date Published: 28 November 2007
PDF: 7 pages
Proc. SPIE 6834, Optical Design and Testing III, 68340P (28 November 2007); doi: 10.1117/12.757720

Published in SPIE Proceedings Vol. 6834:
Optical Design and Testing III
Yongtian Wang; Theo T. Tschudi; Jannick P. Rolland; Kimio Tatsuno, Editor(s)