PRINTER CALIBRATION METHOD AND APPARATUS THEREFOR

To calibrate a printer that prints a full-color image on a recording paper in a color frame sequential fashion, a gray pattern is printed by the printer onto a recording paper, to three color densities of the gray pattern. A recording energy correction amount for magenta is determined based on a difference between the measured magenta density and a set magenta density. Then density variations in yellow and cyan from their set values are estimated that would be resulted from the recording energy correction for magenta. Then recording energy correction amounts for yellow and cyan that reduce the estimated density variations are calculated. Thereafter, density variations in magenta and cyan that would be resulted from the recording energy correction for yellow are estimated, and recording energy correction amounts for magenta and cyan that reduce the estimated density variations are calculated. Also, density variations in magenta and yellow that would be resulted from the recording energy correction for cyan are estimated, and recording energy correction amounts for magenta and yellow that reduce the estimated density variations are calculated. The same procedures are repeated till estimated three color densities approximate the respective set values.