Resolution enhancement methods in optical microscopy for dimensional optical metrology

In this paper, we discuss several enhancement approaches to increase the resolution and sensitivity of optical microscopy as a tool for dimensional nanometrology. Firstly, we discuss a newly developed through-focus microscopy technique providing additional phase information from the afocal images to increase the nanoscale sensitivity of classical microscopy. We also explore different routes to label-free or semiconductor compatible labelling super-resolution microscopy suitable for a broad range of technical applications. We present initial results from, a new wide-field super-resolution imaging technique enabled by Raman scattering. In addition, we discuss super-resolution imaging using NV centres in nano-diamonds as labels and their application in future reference standards.