1. A method for detection and quantification of mura defects in a pattern on a workpiece including: providing a sensor for a parameter to be analyzed, extending a field of the sensor to an extended sensor field by a mechanical movement of the sensor, wherein the extended sensor field crosses at least one dominating direction of mura defects at an angle, thereby providing a sequence of measurements with high internal precision between them, said sequence of measurements crossing the mura defects and extending into a reference area, wherein the mura defects are separated from noise and drift by their different geometrical behavior in the sequence of measurements.