Claims
- 1. A method for calibrating a printer comprising:determining at least one variable print setting to be used on a printer, and using said determined print setting to generate a print setting dependent calibration target having a plurality of printed color samples thereon, said variable print setting being selected from the group including: (a) a selected halftone dot, (b) a selected moiré-creating choice of operation, (c) a selected halftone screen, (d) a selected resolution, and (e) a selected halftone screen frequency; printing said calibration target; measuring each printed color sample in said calibration sheet; and using said measurements to generate a color calibration table for use by said printer in converting device independent colors to device dependent colors.
- 2. The method as defined in claim 1, wherein said selected moiré-creating choice of operation includes a selected dot-overlap function.
- 3. The method as defined in claim 1, wherein a characteristic of said selected halftone dot is used to determine output print color instability.
- 4. The method as defined in claim 3, wherein said halftone characteristic is described as a dispersity value.
- 5. The method as describe in claim 1, wherein said group of variable print settings includes a selected moiré-creating choice of operation in the form of a gray component replacement and under color removal (GCR/UCR) scheme.
- 6. A method for generating a calibration target for calibrating a color printing system, comprising:determining at least one variable print setting to be used on a printer; using said determined print setting to generate a print setting dependent calibration target having a plurality of printed color samples thereon, said variable print setting being selected from the group including: (a) a selected halftone dot, (b) a selected moiré-creating choice of operation, (c) a selected halftone screen, (d) a selected resolution, and (e) a selected halftone screen frequency.
- 7. The method as describe in claim 6, wherein said group of variable print settings includes a moiré-creating choice of operation in the form of a gray component replacement and under color removal (GCR/UCR) scheme.
- 8. The method as defined in claim 6, wherein said selected moiré-creating choice of operation includes a selected dot-overlap function.
- 9. The method as defined in claim 6, wherein a characteristic of said halftone dot is used to determine output print color instability.
- 10. The method as defined in claim 9, wherein said halftone characteristic is described as a dispersity value.
- 11. A method for calibrating a printer comprising:determining at least one variable print setting to be used on a printer, and using said determined print setting to generate a print setting dependent calibration target having a plurality of printed color samples thereon; printing said calibration target; measuring said generated calibration target so as to provide a measured printer response; comparing said measured printer response to a printer model for said printer, and identifying at least one area of non-conformance; generating a second calibration target, dynamically generated to test printer response in the area of non-conformance; secondarily measuring each printed color sample in said second calibration target for providing a respective secondary measured printer response; and using at least one of said measured printer response and secondary measured printer response to generate a color calibration table for use by said printer in converting device independent colors to device dependent colors.
- 12. The method as defined in claim 11, wherein the step of generating a second calibration target further comprises the step of generating an increased number of color samples in one or more regions of printer operational parameters.
- 13. The method as defined in claim 11, wherein the step of generating a second calibration target further comprises the step of generating a reduced number of color samples in one or more smooth color space regions.
- 14. The method as defined in claim 11, further comprising the step of offering an option to use the current calibration or to fine-tune the calibration.
- 15. The method as defined in claim 11, wherein a selected area of non-conformance is determined according to a change in a gradient in a color space of the calibration function as compared to an expected performance.
- 16. The method as defined in claim 11, wherein a selected area of non-conformance is determined according to a change in curvature of the calibration function.
- 17. The method as defined in claim 11, wherein a selected area of non-conformance is determined according to the presence of at least two identical color patches resulting in different measured responses.
CROSS REFERENCE
Cross-reference is made to concurrently filed patent application Ser. No. 09/340,884 by T. Balasubramanian, R. Eschbach and P. Roetling.
US Referenced Citations (14)
Non-Patent Literature Citations (1)
Entry |
Po-Chieh Hung, “Colorimetric Calibration for Scanners and Media”, SPIE, vol. 1448, Camera and Input Scanner System (1991). |