Device for the quantitative assessment of the alignment ot two machine parts, tools or similar

Device comprises a light source (2) emitting light beam (25), first (110) and second (120) two-dimensional opto- electronic sensors. The two sensors can be aligned so that light incident of the opto-electronic surface of the first sensor is partially reflected on to the second sensor. A computer or electronics process the sensor output signals to determine their relative position and the relative position of housing (100) to the incident light beam.