Method and apparatus for multi-color printing using hybrid dot-line halftone composite screens

1. An apparatus for configuring image information for printing of an image having at least three different colors, comprising:

a first halftone screen generator for generating information representing a first color separation image of the image by generating first halftone cells at a first predetermined halftone screen angle wherein pixels within the first halftone cell are oriented in a line structure with increasing cell density from first halftone cell to first halftone cell being identified by stronger line structures;

a second halftone screen generator for generating information representing a second color separation image of the image by generating second halftone cells at a second predetermined halftone screen angle different from the first halftone screen angle and wherein pixels within the second halftone cell are represented in a line structure with increasing cell density from second halftone cell to second halftone cell being identified by stronger line structures, the line structures formed in the second halftone cells being at a different angle than the line structures formed in the first halftone cells; and

a third halftone screen generator for generating information representing a third color separation image of the image by generating third halftone cells in accordance with a line structure dot growth pattern for each of the first halftone screen and second halftone screen of two different screen angles wherein pixels within a third halftone cell are represented by dots with increasing cell density from third halftone cell to third halftone cell being identified by stronger dot structures, the dot structures of the third halftone cells image being ordered along a series of parallel third lines and the series of parallel third lines being generated by a composite first halftone screen and second halftone screen that are formed of the first and second halftone cells.

2. The apparatus of claim 1 and wherein the colors of the first and second color separation images are selected from the group consisting of magenta, cyan, blue and black and the first and second colors are different in color from each other and from the third color.

3. The apparatus of claim 2 and further including a fourth halftone screen generator for generating information representing a fourth color separation image of the image by generating fourth halftone cells at a fourth predetermined halftone screen angle.

4. The apparatus of claim 3 and further including a fifth halftone screen generator for generating information representing a fifth color separation of the image by generating fifth halftone cells at a fifth predetermined halftone screen angle.

5. The apparatus of claim 1 and further including a fourth halftone screen generator for generating information representing a fourth color separation image of the image by generating fourth halftone cells at a fourth predetermined halftone screen angle.

6. The apparatus of claim 5 and further including a fifth halftone screen generator for generating information representing a fifth color separation of the image by generating fifth halftone cells at a fifth predetermined halftone screen angle.

7. The apparatus of claim 6 and wherein the first and second color separation images comprise blue and black, respectively, the third color separation image is cyan, the fourth color separation image is yellow and the fifth color separation is magenta.

8. The apparatus of claim 7 , and wherein the line structures in the blue and black color separation images are perpendicular to each other.

9. An apparatus for configuring image information for printing of an image having at least three different colors, comprising:

a first halftone screen generator for generating information representing a first color separation image of the image by generating first halftone cells at a first predetermined halftone screen angle wherein pixels within the first halftone cell are oriented in a line structure with increasing cell density from first halftone cell to first halftone cell being identified by stronger line structures;

a second halftone screen generator for generating information representing a second color separation image of the image by generating second halftone cells at a second predetermined halftone screen angle different from the first halftone screen angle and wherein pixels within the second halftone cell are represented in a line structure with increasing cell density from second halftone cell to second halftone cell being identified by stronger line structures, the line structures formed in the second halftone cells being at a different angle than the line structures formed in the first halftone cells;

a third halftone screen generator for generating information representing a third color separation image of the image by generating third halftone cells at a third predetermined halftone screen an e wherein pixels within a third halftone cell are represented by dots with increasing cell density from third halftone cell to third halftone cell being identified by stronger dot structures, the dot structures of the third halftone cells image being ordered along a series of parallel third lines and the series of parallel third lines being at a different angle than that of the line structures formed in the first and second halftone cells; and

a fourth halftone screen generator for generating information representing a fourth color separation image of the image using a composite of halftone cell information from two different screen angles with processing of the fourth color separation image in accordance with a line structure dot growth pattern for each of the two different screen angles.

10. The apparatus of claim 6 and wherein the first and second color separation images comprise magenta and cyan, respectively, the third color separation image is black, the fourth color separation image is yellow and the fifth color separation image is blue.

11. The apparatus of claim 3 and wherein the first and second color separation images comprise magenta and cyan, respectively, the third color separation is black and The fourth color separation image is yellow.

12. The apparatus of claim 11 and wherein the yellow color separation image is formed of pixels within a halftone cell that are represented by dots with increasing cell density from halftone cell to halftone cell being identified by stronger dot structures grown in accordance with a dot structure dot growth pattern, the dot structures of the fourth halftone cells being ordered along a series of parallel fourth lines and the series of parallel fourth lines being at a different angle than that of the line structures formed in the first and second halftone cells.

13. The apparatus of claim 3 and wherein the series of parallel fourth lines are at a different angle than that of The series of parallel third lines.

14. The apparatus of claim 1 and wherein the line structures in the first and second halftone screens are perpendicular to each other.

15. A method for configuring image information for printing of an image having at least three different colors, comprising:

generating information representing a first color separation image of the image using a first halftone screen generator, by generating first halftone cells at a first predetermined halftone screen angle wherein pixels within the first halftone cell are oriented in a line structure with increasing cell density from first halftone cell to first halftone cell being identified by stronger line structures;

generating information representing a second color separation image of the image using a second halftone screen generator, by generating separation image of the image by generating second halftone cells at a second predetermined halftone screen angle different from the first halftone screen angle and wherein pixels within the second halftone cell are represented in a line structure with increasing cell density from second halftone cell to second halftone cell being identified by stronger line structures, the line structures formed in the second halftone cells being at a different angle than the line structures formed in the first halftone cells; and

generating information representing a third color separation image of the image using a third halftone screen generator, by generating third halftone cells in accordance with a line structure dot growth pattern for each of the first halftone screen and second halftone screen of two different screen angles wherein pixels within a third halftone cell are represented by dots in accordance with a dot structure growth pattern with increasing cell density from third halftone cell to third halftone cell being identified by stronger dot structures, the dot structures of the third halftone cells image being ordered along a series of parallel third lines and the series of parallel third lines being generated by a composite first halftone screen and second halftone screen that are formed of the first and second halftone cells.

16. The method of claim 15 and wherein the line structures in the first halftone cell and that in the second halftone cell are perpendicular to each other.

17. The method of claim 16 and wherein image information is configured for at least five colors including cyan, magenta, yellow, black and blue.

18. The method of claim 15 and wherein the line structures in the first halftone cell and in the second halftone cell are at an angle of between 53° and 64° to each other.

19. The apparatus of claim 1 and wherein the third halftone screen cell is ordered along two series of crossed parallel lines and the series of crossed parallel lines are at an orthogonal angle to the line structures formed in the first and second halftone cells.

20. The apparatus of claim 1 wherein the line structures formed by the halftone cells with the line structure dot growth pattern are at an angle of between 53° and 64° to each other.

21. The apparatus of claim 4 wherein the first and second color separation images comprise cyan and magenta, respectively; the third color separation image is blue; the fourth color separation image is black; and the fifth color separation is yellow.

22. The apparatus of claim 4 wherein:

the first, second, fourth, and fifth screen is formed with traditional color separation image comprise cyan, magenta, black, and yellow color of color screen of 15°, 75°, 45°, and 0° screen angles; and

the third screen is a composite screen for the fifth color.

23. The apparatus of claim 4 wherein the fifth color separation image is blue.

24. The apparatus of claim 1 and wherein the line structures formed by the halftone cells with the line structure dot growth pattern are at an angle of between 53° and 64° to each other.