Patent US5594557A successfully refreshed from Google Patents.
US5594557A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Color printer calibration correcting for local printer non-linearities
Assignee: Xerox Corp
•
Filing: 1994-10-03
•
Granted: 1997-01-14
•
Expires: 2014-10-03
Abstract
Abstract A color printer calibration method for improving printer accuracy in regions of local non-linearity includes the steps of: a) starting with filled rectangular array of color mappings A 0 mapping printer signals to device independent color space signals; b) empirically deriving a set of color mappings P i in an area of interest; c) using a set of planes defined by the color mappings of A 0 , and the set of empirically derived color mappings P i , identifying a new set of planes such that each point defined by A 0 and each point defined by P i is located at the intersection of three planes, the intersection points of this expanded number of planes defining a set of points P i (expanded) that define a full rectangular array A 1 of mappings including mappings A 0 , mappings P i and mappings P i (expanded) ; d) storing the mapping A 1 for use in the creation of a new color space transformation LUT for use with the printer.
Inventors
- 👤 Robert J. Rolleston
- 👤 Martin S. Maltz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 12:19
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/46; H04N1/56; H04N1/60; H04N1/603; H04N1/6033
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
253 words
A method of improving calibration in a calibrated color printing system, the color printing system having a calibration derived from a filled rectangular array of color mappings defined by a first color mapping set A 0 , in which printer signals are mapped to colorimetric signals throughout the gamut of the color printing system, including the steps of: a) empirically generating a second color mapping set P i , mapping printer signals to colorimetric signals, said second color mapping set P i smaller than the first color mapping set A 0 and overlapping a portion of the printer gamut therewith; b) using said second color mapping set P i and a first set of planes corresponding to the first color mapping set A 0 , identifying an expanded set of planes in which each mapping in the first color mapping set A 0 and each mapping in said second color mapping set P i are defined by points located at an intersection of three planes, the intersecting points of the expanded number of planes defining a set of points P i (expanded) corresponding to a third color mapping set P i (expanded) ; c) generating a full rectangular array of color mappings defined by color mapping set A 1 , from the first color set mapping A 0 , said second color set mappings P i and said third color mapping set P i (expanded) ; d) generating a new calibration for said printing system derived from said color mappings A 1 .
Claim 2
Independent Claim
253 words
A method of improving calibration in a calibrated color printing system, the color printing system having a calibration derived from a filled rectangular array of color mappings defined by a first color mapping set A 0 , in which printer signals are mapped to colorimetric signals throughout the gamut of the color printing system, including the steps of: a) empirically generating a second color mapping set P i , mapping printer signals to colorimetric signals, said second color mapping set P i smaller than the first color mapping set A 0 and overlapping a portion of the printer gamut therewith; b) using said second color mapping set P i and a first set of planes corresponding to the first color mapping set A 0 , identifying an expanded set of planes in which each mapping in the first color mapping set A 0 and each mapping in said second color mapping set P i are defined by points located at an intersection of three planes, the intersecting points of the expanded number of planes defining a set of points P i (expanded) corresponding to a third color mapping set P i (expanded) ; c) generating a full rectangular array of color mappings defined by color mapping set A 1 , from the first color set mapping A 0 , said second color set mappings P i and said third color mapping set P i (expanded) ; d) generating a new calibration for said printing system derived from said color mappings A 1 .
Claim 3
Dependent Claim
51 words
The method as defined in claim 1, wherein said step of generating a full rectangular array of color mappings defined by color mapping set A 1 includes the substep of using any empirically derived mapping from color mapping sets A 0 or P i in place of a non-empirically derived mapping.
Claim 4
Dependent Claim
62 words
The method as defined in claim 1, wherein said step of generating a full rectangular array of color mappings defined by color mapping set A 1 includes the substep replacing any mappings in third color mapping set P i (expanded) that are near mappings of second color mapping set P i , with mappings which take into account the P i mappings.
Claim 5
Dependent Claim
260 words
A calibrated color printing system, the color printing system having a calibration stored in a calibration memory derived from a filled rectangular array of color mappings defined by a first color mapping set A 0 , in which printer signals are mapped to colorimetric signals throughout a gamut of the color printing system, including the steps of: a) means for empirically generating a second color mapping set P i , mapping printer signals to colorimetric signals, said second color mapping set P i smaller than the first color mapping set A 0 and overlapping a portion of the printer gamut therewith; b) means for using said second color mapping set P i and a first set of planes corresponding to the first color mapping set A 0 , identifying an expanded set of planes in which each mapping in the first color mapping set A 0 and each mapping in said second color mapping set P i are defined by points located at an intersection of three planes, the intersecting points of the expanded number of planes defining a set of points P i (expanded) corresponding to a third color mapping set P i (expanded) ; c) means for generating a full rectangular array of color mappings defined by color mapping set A 1 , from the first color set mapping A 0 , said second color set mappings P i and said third color mapping set P i (expanded) ; d) means for generating a new calibration for said printing system derived from said color mappings A 1 .
Claim 6
Dependent Claim
260 words
A calibrated color printing system, the color printing system having a calibration stored in a calibration memory derived from a filled rectangular array of color mappings defined by a first color mapping set A 0 , in which printer signals are mapped to colorimetric signals throughout a gamut of the color printing system, including the steps of: a) means for empirically generating a second color mapping set P i , mapping printer signals to colorimetric signals, said second color mapping set P i smaller than the first color mapping set A 0 and overlapping a portion of the printer gamut therewith; b) means for using said second color mapping set P i and a first set of planes corresponding to the first color mapping set A 0 , identifying an expanded set of planes in which each mapping in the first color mapping set A 0 and each mapping in said second color mapping set P i are defined by points located at an intersection of three planes, the intersecting points of the expanded number of planes defining a set of points P i (expanded) corresponding to a third color mapping set P i (expanded) ; c) means for generating a full rectangular array of color mappings defined by color mapping set A 1 , from the first color set mapping A 0 , said second color set mappings P i and said third color mapping set P i (expanded) ; d) means for generating a new calibration for said printing system derived from said color mappings A 1 .
Claim 7
Dependent Claim
50 words
The device as defined in claim 4, wherein said means for generating a full rectangular array of color mappings defined by color mapping set A 1 includes means for using any empirically derived mapping from color mapping sets A 0 or P i in place of a non-empirically derived mapping.
Claim 8
Dependent Claim
62 words
The device as defined in claim 4, wherein said means for generating a full rectangular array of color mappings defined by color mapping set A 1 includes means for replacing any mappings in third color mapping set P i (expanded) that are near mappings of second color mapping set P i , with mappings which take into account the P i mappings.
Claim 9
Independent Claim
353 words
A method of recalibrating a color printing system in a color space region of non-linearity, the color printing system having a first calibration stored in a calibration memory, said first calibration derived from a filled rectangular array of color mappings defined by a first color mapping set A 0 , in which printer signals are mapped to colorimetric response signals throughout a gamut of the color printing system, including the steps of: a) directing a correction set of printer signals to said printing system to print a set of color patches with colorants on a medium corresponding to a color space region of non-linearity; b) measuring colorimetric response of said printer in said color space region of non-linearity from said set of color patches and generating colorimetric response signals indicative thereof; c) generating a second color mapping set P i , mapping the correction set of printer signals to colorimetric response signals, said second color mapping set P i smaller than the first color mapping set A 0 and overlapping a portion of the printer gamut therewith; d) using said second color mapping set P i and a first set of planes corresponding to the first color mapping set A 0 , identifying an expanded set of planes in which each mapping in the first color mapping set A 0 and each mapping in said second color mapping set P i are defined by points located at an intersection of three planes, the intersecting points of the expanded number of planes defining a set of points P i (expanded) corresponding to a third color mapping set P i (expanded) ; e) generating a full rectangular array of color mappings defined by color mapping set A 1 , from the first color set mapping A 0 , said second color set mappings P i and said third color mapping set P i (expanded) ; f) applying an inverse interpolation process to said color mapping set A 1 to derive a new mapping of colorimetric response signals to printer signals, addressable by said colorimetric response signals, thereby generating a new calibration for said printing system.
Claim 10
Independent Claim
353 words
A method of recalibrating a color printing system in a color space region of non-linearity, the color printing system having a first calibration stored in a calibration memory, said first calibration derived from a filled rectangular array of color mappings defined by a first color mapping set A 0 , in which printer signals are mapped to colorimetric response signals throughout a gamut of the color printing system, including the steps of: a) directing a correction set of printer signals to said printing system to print a set of color patches with colorants on a medium corresponding to a color space region of non-linearity; b) measuring colorimetric response of said printer in said color space region of non-linearity from said set of color patches and generating colorimetric response signals indicative thereof; c) generating a second color mapping set P i , mapping the correction set of printer signals to colorimetric response signals, said second color mapping set P i smaller than the first color mapping set A 0 and overlapping a portion of the printer gamut therewith; d) using said second color mapping set P i and a first set of planes corresponding to the first color mapping set A 0 , identifying an expanded set of planes in which each mapping in the first color mapping set A 0 and each mapping in said second color mapping set P i are defined by points located at an intersection of three planes, the intersecting points of the expanded number of planes defining a set of points P i (expanded) corresponding to a third color mapping set P i (expanded) ; e) generating a full rectangular array of color mappings defined by color mapping set A 1 , from the first color set mapping A 0 , said second color set mappings P i and said third color mapping set P i (expanded) ; f) applying an inverse interpolation process to said color mapping set A 1 to derive a new mapping of colorimetric response signals to printer signals, addressable by said colorimetric response signals, thereby generating a new calibration for said printing system.
Claim 11
Dependent Claim
52 words
The method as defined in claim 7, wherein said step of generating a full rectangular array of color mappings defined by first color mapping set A 1 includes means for using any measured colorimetric response mapping from color mapping sets A 0 or P i in place of an interpolation derived mapping.
Claim 12
Dependent Claim
62 words
The method as defined in claim 7, wherein said step of generating a full rectangular array of color mappings defined by color mapping set A 1 includes means for replacing any mappings in third color mapping set P i (expanded) that are near mappings of second color mapping set P i , with mappings which take into account the P i mappings.
References Cited (Backward Citations)
US2790844A
Cited
US4275413A
Cited
US4500919A
Cited
US4992861A
Cited
US4941039A
Cited
US5311332A
Cited
US5296923A
Cited
US5428465A
Cited
US5305119A
Cited
US5390035A
Cited
US5323249A
Cited
US5377041A
Cited
US5416613A
Cited
US5471324A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-01-14 | 2000-07-15 | 2001-01-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-01-14 | 2004-07-15 | 2005-01-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-01-14 | 2008-07-15 | 2009-01-14 | $7700.00 | Window Closed / Lapsed |