An analytic method of constructing high fidelity clustered halftone dots is presented.A phase addressable cell space is created which provides numerically precise 2D edge position information. Exposures are produced with variable intensity modulation to phase shift process direction dot edges, and fine granularity timing is used to adjust fast scan direction edges. This allows symmetrically thresholded halftone dots instead of sequentially thresholded dots. Advantages of this technique are more binary halftone gray levels, reduced labor content, spline based tone correction, device independence, and arbitrary screen angle and frequency. An equation which provides the desired shape and tone response over the intensity range is developed and analyzed. Shape information is extracted which is independent of the target printer characteristics. Highly accurate tone information is obtained by integrating the continuous shape function. A printer-dependent, gray enabled modulator drive function is utilized, and step wedge prints are mae with a nominal tone reproduction curve (TRC). Data from densitometer measurements are converted to spline format, and used to correct the nominal TRC with high relative accuracy. Resulting contourless tone corrected prints show very good linearity and shape definition over the entire intensity range.
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