Claims
- 1. A method for printing an image; said method comprising:executing plural passes of a printhead over a printing medium, each pass forming a swath of marks on the medium; and between printing passes of the printhead, stepping the printing medium by a nonzero step distance that varies by at least ten pixels as between steps, but is always in a forward direction and less than three-quarters of a swath height; and wherein: pen masking is not used, except for masking necessary for swath alignment.
- 2. The method of claim 1, wherein:the step distance substantially alternates between two distinct values.
- 3. The method of claim 1, wherein:substantially no two swath edges coincide within one-twentieth of the height of the shallowest swath.
- 4. The method of claim 1, wherein:the step distance varies at substantially every step.
- 5. The method of claim 1, wherein:the step distance substantially rotates among plural distinct values.
- 6. The method of claim 5, wherein:the step distance substantially rotates among said plural distinct values in a predetermined sequence of said values.
- 7. Apparatus for printing an image on a printing medium; said apparatus comprising:a printhead; means for passing the printhead over such medium multiple times, each pass forming a swath of marks on such medium; and means for spacing edges of each swath away from edges of substantially each other swath by at least ten pixels, but always less than three-quarters of a swath height so that substantially no two swath edges coincide on such medium; and wherein: pen masking is not used, except for masking necessary for swath alignment.
- 8. The apparatus of claim 7, wherein:the spacing means further comprise means for modifying a spatial frequency of banding effects produced by the apparatus.
- 9. The apparatus of claim 7, wherein:the spacing means comprise means for spacing the edges of swaths from each other by a distance that is substantially random or randomized.
- 10. The apparatus of claim 7:further comprising an installed algorithm for accommodating print-medium-advance-axis error; and wherein: the spacing means comprise means for adapting the error-accommodating algorithm to space the swath edges away from each other.
- 11. The apparatus of claim 7, wherein:the spacing means comprise means for spacing the swath edges well away from each other, namely at least one-twentieth of the swath dimension in a direction of printing-medium advance.
CROSS REFERENCE TO RELATED APPLICATION(S)
This is a divisional of application Ser. No. 09/516,816 filed on Mar. 1, 2000, now U.S. Pat. No. 6,336,702 which is hereby incorporated by reference herein.
US Referenced Citations (2)
Number |
Name |
Date |
Kind |
6086181 |
Majette et al. |
Jul 2000 |
A |
6336702 |
Zapata et al. |
Jan 2002 |
B1 |