Granted Patent B2

US 7,426,033 · App. 11/748,277 · Granted Sep 16, 2008

Abstract

Claims (37)

1. A method for characterizing a color variation of a color output device, the method comprising:

printing a set of similar color patches using the color output device;

determining colorimetric values for each color patch;

calculating a standard deviation value for each of the colorimetric values;

calculating a numerical value that is a function of the standard deviation values and that represents a colorimetric deviation of the set;

characterizing the color variation of the color output device based on the calculated numerical value; and

outputting a signal representative of the characterized color variation.

2. The method of claim 1 , wherein the color output device is a color printer.

3. The method of claim 1 , wherein the color output device is a color copier.

4. The method of claim 1 , wherein the color output device is a color printing press.

5. The method of claim 1 , wherein the color patches comprise predetermined percentages of cyan, magenta, yellow and black colorants.

6. The method of claim 1 , wherein printing further comprises printing the set of similar color patches on an output page.

7. The method of claim 1 , wherein printing further comprises printing the set of similar color patches on a plurality of output pages.

8. The method of claim 1 , wherein the colorimetric values comprise L, a and b values.

9. The method of claim 1 , wherein the colorimetric values comprise X, Y and Z values.

10. The method of claim 1 , wherein determining further comprises measuring the color patches using a colorimeter.

11. The method of claim 1 , wherein determining further comprises measuring the color patches using a spectrophotometer.

12. The method of claim 1 , wherein determining further comprises measuring the color patches using a spectrocolorimeter.

13. The method of claim 1 , wherein the function comprises a sum of squares of the standard deviation values.

14. The method of claim 1 , wherein the function comprises a square root of a sum of squares of the standard deviation values.

15. A system for characterizing color variations in a color output device, the system comprising:

an image file comprising a set of similar color patches, the image file adapted to be printed on the color output device;

a means for determining colorimetric values for each printed color patch; and

a means for calculating a standard deviation value for each of the colorimetric values, and a numerical value that is a function of the standard deviation values and that represents a colorimetric characterization of color deviation of the set.

16. The system of claim 15 , wherein the color output device is a color printer.

17. The system of claim 15 , wherein the color output device is a color copier.

18. The system of claim 15 , wherein the color output device is a color printing press.

19. The system of claim 15 , wherein the color patches comprise predetermined percentages of cyan, magenta, yellow and black colorants.

20. The system of claim 15 , wherein the set of similar color patches are printed on an output page.

21. The system of claim 15 , wherein the set of similar color patches are printed on a plurality of output pages.

22. The system of claim 15 , wherein the colorimetric values comprise L, a and b values.

23. The system of claim 15 , wherein the colorimetric values comprise X, Y and Z values.

24. The system of claim 15 , wherein the measuring device comprises a colorimeter.

25. The system of claim 15 , wherein the measuring device comprises a spectrophotometer.

26. The system of claim 15 , wherein the measuring device comprises a spectrocolorimeter.

27. The system of claim 15 , wherein the function comprises a sum of squares of the standard deviation values.

28. The system of claim 15 , wherein the function comprises a square root of a sum of squares of the standard deviation values.

Assignments (9)