Patent attributes
A laser spot tracker comprising a quadrant detector. A portion of a spot of laser light reflected from an object being illuminated (OBI) may be defocused to occupy a significant portion such as one-third of the field of view, while another portion remains focused, therefore allowing for quick calculation of the spot centroid. With such a “composite spot”, multiple target (OBI) positions may simultaneously be defined in elevation and azimuth with respect to null by analyzing the energy in each quadrant. The X and Y angle information (off null) for multiple targets (OBIs), and their codes may be displayed. For a large, defocused spot, two segmented multi-element detectors may be used, one in front of and the other behind the focal plane to reduce the effects of hot spots in a spot of laser light collected from an object being illuminated.
