System and method for image analysis pointing-error correction

An optical interrogation system having scan beam pointing-error correction, comprising:

• an illuminator that emits an optical scan beam at normal incidence towards a biosensor;
• a receiver that collects the optical beams at normal incidence from the biosensor and then outputs a signal which corresponds to the collected optical beam;
• and
• a processor to process the output signals from the receiver to determine and correct the optical beam x-pointing-error, y-pointing-error, or both x- and y-pointing-error, wherein beam pointing error is corrected by numerically eliminating selected optical beam scan lines received from the biosensor, and the optical beam scan lines are numerically selected for eliminating by disregarding a beam scan line if the scan line does not include a selected region of the biosensor.