US Patent 9519976 Calibrating stereoscopic cameras

A stereoscopic camera calibration target includes: first illumination points on a first surface; second illumination points on a second surface, the first and second surfaces being planar, parallel to each other, and spaced from each other; and circuitry that sets a strobe frequency of the first and second illumination points. A method includes: moving a calibration target in front of a stereoscopic camera, the calibration target comprising first points on a first surface and second points on a second surface, the first and second surfaces being planar, parallel to each other, and spaced from each other; capturing, using the stereoscopic camera, an image sequence of the calibration target, the image sequence comprising pairs of left and right images of at least some of the first and second points; determining a calibration value for the stereoscopic camera using the image sequence; and processing the image sequence using the calibration value.