Patent ID: 8493573

Claim:
A method for high-resolution optical position sensing using an optical system based on sparse, low-resolution detectors, said method comprising: introducing light onto an array of detectors, wherein said light is characterized as an input beam incident as a spot of Gaussian-shaped intensity on the array; a plurality of said detectors producing detector signals when said spot of Gaussian-shaped intensity on the array spreads beyond an individual detector element; receiving and digitizing said detector signals at a sampling rate having a sampling interval for digital signal processing, wherein said digitized detector signals are normalized; computing in a digital signal processor a functional computational model based on expected signals as a function of the spot's lateral x and y coordinates, and likewise normalizing said expected signals; computing in said digital signal processor differences between said digitized detector signals and said expected signals at each x and y coordinate location in a sensor plane for each detector; computing in said digital signal processor a residual error function from the sum of the squares of the differences for all detectors at any x and y coordinate location, and determining the minimum value of said residual error function; computing in said digital signal processor a location of the minimum value of said residual error function to derive a minimum least squares estimate of the input beam position in x and y coordinate values; converting in said digital signal processor the estimated input beam position coordinate to a two-dimensional angular coordinate in azimuth and elevation values; and outputting a location of a distant localized optical source of said input beam as either a digital readout or on a sensor display.