Method of printing with overlapped segements of printhead
View Patent ↗A method of printing with overlapped segments of a segmented printhead is provided in which at least one temperature sensor on the printhead measures temperatures of adjacent segments to determine an overlapped region of the adjacent segments, an overlap signal indicative of the determined overlapped region is output from the temperature sensor to a half toning circuit, and the half toning circuit adjusts, using the received overlap signal, a half toning firing pattern of a continuous tone image for coextensive nozzles of the adjacent segments within the determined overlapped region such that V A +V B is greater than V, where V A and V B are respective independent dither matrix values of the adjacent segments and V is a continuous tone value to be represented.
1. A method of printing with overlapped segments of a segmented printhead, the method comprising the steps of:
measuring, with at least one temperature sensor on the printhead, temperatures of adjacent segments to determine an overlapped region of the adjacent segments;
outputting, from the at least one temperature sensor to a half toning circuit, an overlap signal indicative of the determined overlapped region; and
adjusting, using the half toning circuit and received overlap signal, a half toning firing pattern of a continuous tone image for coextensive nozzles of the adjacent segments within the determined overlapped region such that V A +V B is greater than V, where V A and V B are respective independent dither matrix values of the adjacent segments and V is a continuous tone value to be represented.
2. A method as claimed in claim 1 wherein, in the adjusting step, the firing pattern is adjusted so that the coextensive nozzles of the adjacent segments never both fire at the same time.
3. A method as claimed in claim 1 , wherein, in the adjusting step, the firing pattern is adjusted so that the coextensive nozzles of the adjacent segments never both produce an output.
4. A method as claimed in claim 1 , further including the step of assigning an output dot to one coextensive nozzle stochastically according to a probability given by a current interpolation factor of an interpolation function used to create the half toning firing pattern.
5. A method as claimed in claim 1 wherein the half toning firing pattern is created using a dither matrix with an interpolation function.
6. A method as claimed in claim 5 wherein, in the adjusting step, the output from the dither matrix and an overlap signal derived from the determined overlapped region are summed.
7. A method as claimed in claim 6 wherein, in the adjusting step, the summed output and signal are compared to continuous tone data to determine half tone data for the coextensive nozzles of the adjacent segments.
8. A method as claimed in claim 6 wherein the summed output and signal are subtracted from the continuous tone data to determine the half tone data.
9. A method as claimed in claim 1 wherein, in the measuring step, the temperature of each segment is measured by a temperature sensor on each respective segment.