GRAPHICAL ToF PHASE UNWRAPPING

A computing system, comprising:

• a logic machine;
• and
• a storage machine holding instructions executable by the logic machine to
• generate a plurality of phase order sets from a reference phase vector in K-dimensional space, the reference phase vector describing an evolution of phase with distance for K frequencies of amplitude modulated light,
• based on the plurality of phase order sets, generate a corresponding plurality of parallel lines in K-dimensional space, each parallel line having a point corresponding to a phase order set and a slope parallel to the reference phase vector,
• project the plurality of parallel lines onto a lower dimensional plane in the K-dimensional space, thereby forming a matrix of points from intersections of the parallel lines with the lower dimensional plane,
• plot independent terms through the matrix of points,
• generate a look-up table that identifies a phase order set based on two or more of the independent terms, and
• store the matrix of points and the look-up table for use in phase unwrapping.

A method of performing phase unwrapping using a predetermined matrix of points and a look-up table, the method comprising:

• making K phase measurements each at a different modulation frequency of the K modulation frequencies to form a set of noisy phase measurements;
• determining a set of independent terms of the predetermined matrix of points based on the set of noisy phase measurements in a K-dimensional phase space, the predetermined matrix of points comprising points in a lower dimensional plane in the K-dimensional phase space, each point in the predetermined matrix of points representing a corresponding predetermined noisy phase order set with known noise;
• locating a corresponding set of noiseless phase orders by using the set of independent terms to reference the look-up table;
• determining a distance value for the pixel based upon the corresponding set of noiseless phase orders;
• and
• outputting the distance value for the pixel.