The Excillum NanoTube N3 is based on advanced electron optics and the latest tungsten-diamond transmission target technology. Automatic e-beam focusing and astigmatism correction ensures that the smallest possible, truly round spot is achieved every time, every day. The NanoTube N3 also has the unique feature of internally measuring and reporting the current spot size. In addition, advanced cooling and thermal design results in extreme stability over long exposures. This enables an unprecedented true resolution of 150 nm lines and spaces.