The image processing tools used are working in the sub pixel range that means a measurement with an accuracy of up to 1/40 pixels can be carried out. There is a wide selection of evaluation tools available, here to count among other things:
- distance measurement of edges
- measurement of radii and circle sections
- determination of the roundness of a circle
- measuring the distances of objects to each other
- measurement of distances between circles and edges
- intersection calculations of various kinds
- calculation of distances using trigonometric functions
It is possible to convert all pixel readings in a defined unit (for example millimeters) by linear and nonlinear calibration functions.
The following images show filters which different edges with different measuring tools were made visible. It can be seen that even edges with a very low contrast can be detected by the image processing routines we use.