Measurement Principle:

The Nanofinger® sensor is driven by a special high speed electronics that reacts with a bandwidth of several KHz. The Nanofinger® sensor is moved towards a sample in closed loop with 1 nm increments until it reaches the desired signal value (e.g. at 75% amplitude). At this moment the position of the stage that moves this sensor is stored as coordinate data. The Nanofinger® sensor s removed again and then moved aside for the next approach, at any time in closed loop with 1 nm increments:

"Contact" in the upper pictures means: The pre-defined distance of a few Nanometers detected with the Nanofinger® sensor. The upper algorithms are independent from the size of the increments. A point to point distance of a few Nanometers allows ultra high resolution measurements. A point to point distance of hundreds of microns or even a millimeter allows fast overview measurements or the fast precise detection of coordinates. The smallest increment is 1 (one!) Nanometer.

Speed is nearly independent from stroke:

There are two ways to scan a sample:
1. A scan with highest resolution over the whole stroke => extremely big data field and several hours of measurement time. This is the method how a profilometer and an AFM must work: as soon as their tip is in contact with the sample it must keep contact until to the end of the scan. This can be extremely time consuming, and the measurement time is proportional to the scan range.
But the upper algorithm of the 3D-Nanofinger® offers a much more effective and faster method:

2. An area of interest is scanned with a low amount of data points to get the overview picture on the screen. This can be done e.g. within a few minutes per Linescan. In a second step smaller sub-areas of the sample can be addressed to start a new scan only within that area (in about the same time), instead of zooming into the data points by software. This method is much faster, because only the regions of interest are measured in high resolution.

Expanded to 3D:

Since all movement axes of the 3D-Nanofinger® are with 1 nm resolution equal in quality, it is easy to prepare a 3D image by making arrays of Linescans.

Or along an inner or outer Contour:

Since all movement axes of the 3D-Nanofinger® are equal in quality, this machine can also measure along a 3D-path, e.g. along an inner or outer contour. The algorithm is similar to the upper version of the Linescan.

It is easy to measure e.g. the inner diameters of small holes, down to 0.2 mm diameter. When arrays of these contour measurements are made it is possible to determine the orientation of an object by finding e.g. its central axis in 3D.