75µm

Signal/Noise ratio, S/N = 20 (GK = 1,0)


Important!

This is an R type sensor registration, where the sensor constant has been selected to GK = 1,0.
The smallest detectable crack depth with a good signal/noise ratio, S/N, on a smooth surface, is approximately obtained by the following calculation:
DJspr = GK/50.
DJspr = 1,0/50 = 0,021 = 20µm (approx.).
Within limits, the crack signal S, is proportional to the crack depth.
For 0,075 mm deep crack, like in this case, with a S/N = 20, you will  obtain with a S/N = 5, a detectable crack depth DJspr = 5/20 x 0,075 = 0,01875 = 19µm (approx.).
Please note that this is on a fine, smooth surface!