High-resolution optical position sensing is disclosed using sparse, low-resolution detectors. Precise location of two-dimensional position or angular orientation of an optical beam at the focal plane of a sensor system is made possible using sparse low-resolution detectors. The beam may be emitted directly from a source, or scattered from a remote target. The high precision in determining the beam or focal spot location is the result of a novel data processing and analysis method for the signals from the low-resolution detectors.