fig1 the corresponding moir u00e9 pattern is also a grid which is magnified represented also with squares in dotted lines for facilitating the understanding the horizontal position of the magnified grid may be used for determining the horizontal position between the information carrier and the array of light spots while the vertical position of the magnified grid may be used for determining the vertical position between the information carrier and the array of light spots similarly as the tracking of light blobs b 1 and b 2 described previously in case of an angular misalignment between the information carrier and the array of light spots the moir u00e9 pattern is also rotated according to 2 fig1 illustrates the case with a misalignment u03b8 of 5 degrees it can be shown from 2 that the angular misalignment u03b8 may be derived from the following relation where t is the period of the global moir u00e9 pattern detected on the detection area 107 coming back to fig1 the system also comprises a processing unit 116 intended to perform calculations from the different moir u00e9 patterns detected and generated by the detector 106 and carried as signals via a data bus 117 the processing can be done by.