Understand Noise At The Sub-nanometer Scale

Every positioner has some level of uncertainty in its position, some slight amount of movement that contributes noise to a measurement. The question is whether that uncertainty—also known as position noise—is tolerable for a given device and a given application. Most manufacturers of nanopositioning systems specify their noise, but for a customer to make an informed decision, they must have some understanding of what that noise specification means. That cannot be expressed in a single value, but should be shown as a spectrum that plots noise over frequency and separates the noise from different axes. Armed with such information, users can be sure they're getting a low noise,high-precision system that meets their needs.