Components of a Nanopositioning System
Nanopositioning systems provide the opportunity to enable many advanced applications. Their use has spread from AFMs to optics and multiple new technologies. While selecting a system can be complex at times, there are three main components that work together to provide motion on the nanoscale. Each component will briefly be discussed and can be studied in greater detail via the available links.
Component 1 – Piezo Stage
The piezo or nanopositioning stage provides actual motion for the system. Piezo flexure stages come in many different shapes and sizes for a variety of applications. Several catalog products are available, however certain applications require an adaptation or entirely custom stage. Nanopositioning stages can be categorized by axis or function. Examples include single axis, XY, XYZ and tip/tilt.
Component 2 – Closed-Loop Controller or Open-Loop Driver
The controller or driver provides power to the piezo stage. In a closed-loop system the piezo stage also has a sensor which provides position data to the controller. The controller processes this information and makes changes on the fly to ensure commanded position. It is important to select a controller that has the corresponding amount of channels to match the stage. As an example, a single channel controller should be mated to a single axis piezo stage, while a three axis piezo stage would require a three channel controller.
Component 3 – Software and System Interface
Often times the nanopositioning system is a component of a larger device. It is important to integrate the system hardware so that everything works in harmony. There are multiple ways to communicate with nPoint electronics to drive the stage. The most common is through the -10V to 10V BNC analog input. The user can also integrate using multiple interfaces via USB, Digital I/O, PFM, Ethernet, High-Speed Parallel, or Digital Encoder. nPControl software is included with every nPoint controller. This provides control-loop tuning of PID parameters and notch filters, internal waveform generation, high-resolution recording, trajectory generation, and raster scanning. Controllers are also compatible with a variety of software packages including EPICS, ScanImage, Nikon Elements, LabView and MicroManager. nPoint also provides custom software and firmware development when a better fit for the application.
nPControl Software Window
When considering a nanopositioning system to enable an application, it is important to determine how each component will fit. There are a multitude of factors that go into every component, and each must be employed to provide the fast, accurate motion often associated with piezo stages.