Centroid locating sensors having plural spatial filtering logic circuits connected to plural digitization comparators and methods for locating an illuminated spot on a detector

A centroid-locating sensor comprising:

• a plurality of photo-diode (PD) detector elements arranged in an array;
• a plurality of digitization comparators connected to the plurality of PD detector elements, the digitization comparators configured to receive output signals from the plurality of PD detector elements and generate a binary 1 output when the output from at least one of the PD detector elements exceeds a threshold set point and generate a binary 0 output when the output is below the threshold set point;
• and
• a plurality of spatial filtering logic circuits connected to the digitization comparators, the plurality of spatial filtering logic circuits configured to receive an output from the plurality of digitization comparators, wherein each of the plurality of spatial filtering logic circuits is configured to receive outputs from a plurality of the PD detector elements defining a group of PD detector elements, the plurality of spatial filtering logic circuits configured to reject noise for one of the PD detector elements of the group of PD detector elements having a binary 1 output based on the output of at least one other PD detector element of the group of PD detector elements.