Performance advances in interferometric optical profilers for imaging and testing

Abstract

Interferometric optical profilers deliver non-contact, fast, full-field measurements with vertical resolution down to a fraction of a nanometer. Over the last decade advancements to these instruments have allowed for the analysis of not only static but also dynamic objects, like cantilevers and other microelectromechanical system devices, moving or vibrating at up to 1 MHz frequencies. Special objectives and illumination allow for imaging and testing of objects enclosed in environmental or protective chambers or immersed in liquids—including biological samples. Advanced analysis of the interference signal allows for the measurement not just of the surface profile but also transparent coatings.