Automated image appearance control method
View Patent ↗An input image capture device, capable of sampling the color density and gloss of the fused printed image (thus not requiring the printing of density patches on a separate calibration page), may compare the printed image's color density and gloss to a predicted value. Then, appearance control may be achieved by changing fuser parameters (such as fuser nip width, fuser roller temperature and the like) and other electrophotographic element control parameters (such as exposure, off-set development voltage, charger voltage and the like) to maintain a desirable constant appearance (density, gloss, etc.) of images consistently in print engine usage (within a print run and between print runs), even if different media substrates are used on the same print job. Therefore, no waste calibration sheet is needed, and a print job operator may receive more timely feedback relating to the current printing job stream.
1. A method for controlling an appearance of a printed image on a media substrate comprising:
measuring at least one of an actual color density and an actual gloss of at least a first measured portion and a second measured portion, respectively, of the printed image;
comparing at least one of the actual color density and the actual gloss with a predetermined value of color density and a predetermined value of gloss, respectively; and
adjusting the appearance as necessary to bring at least one of the actual color density and the actual gloss closer to the predetermined color density and the predetermined gloss, respectively,
wherein the first measured portion and the second measured portion are the same portion of the printed image, and
wherein the first measured portion and the second measured portion comprise a multiple strip width along a width of the printed page.
2. A method for controlling an appearance of a printed image on a media substrate comprising:
measuring at least one of an actual color density and an actual gloss of at least a first measured portion and a second measured portion, respectively, of the printed image;
comparing at least one of the actual color density and the actual gloss with a predetermined value of color density and a predetermined value of gloss, respectively;
adjusting the appearance as necessary to bring at least one of the actual color density and the actual gloss closer to the predetermined color density and the predetermined gloss, respectively; and
measuring a pre-fused color toner transmission density to determine information about toner lay-down prior to the printed image being fused.
3. A method for controlling an appearance of a printed image on a media substrate comprising:
calculating a predicted gloss and a predicted color density of at least a predicted portion of the printed image, the calculation based on a digital bit map of the printed image and the media substrate;
measuring an actual color density and an actual gloss of at least a measured portion of the printed image;
comparing the actual color density with the predicted color density;
comparing the actual gloss with the predicted gloss; and
adjusting the appearance as necessary to bring at least one of the actual color density and the actual gloss closer to the predicted color density and the predicted gloss, respectively.
4. The method according to claim 3 , further comprising:
adjusting the gloss by changing at least one of a fuser nip width and a fuser roller temperature; and
adjusting the color density by changing at least one of a toner lay-down amount, an exposure, an off-set voltage and a charger voltage.
5. The method according to claim 3 , further comprising measuring a pre-fused color toner patch transmission density to determine information about toner lay-down prior to the printed image being fused.
6. The method according to claim 3 , wherein the measured portion and the predicted portion are the same portion of the printed image.
7. The method according to claim 6 , wherein the measured portion and the predicted portion is a strip width of the printed image.
8. A method for controlling an appearance of a printed image on a media substrate comprising:
calculating a predicted gloss and a predicted color density of at least a predicted portion of the printed image, the calculation based on a digital bit map of the printed image and the media substrate;
measuring a pre-fused color toner patch transmission density to determine information about toner lay-down prior to the printed image being fused;
measuring an actual color density and an actual gloss of at least a measured portion of the printed image;
comparing the actual color density with the predicted color density;
comparing the actual gloss with the predicted gloss;
adjusting the actual gloss as necessary by changing at least one of a fuser nip width and a fuser roller temperature; and
adjusting the actual color density as necessary by changing at least one of a toner lay-down amount, an exposure, an off-set voltage and a charger voltage.
9. A method for monitoring printed image quality during a print run without requiring the printing of a calibration sheet comprising:
calculating a predicted gloss and a predicted color density of at least a strip width of the printed image, the calculation based on a digital bit map of the printed image and the media substrate;
measuring an actual gloss and an actual color density of at least the strip width of the printed image;
comparing the actual color density with the predicted color density;
comparing the actual gloss with the predicted gloss; and
adjusting the appearance as necessary to bring at least one of the actual color density and the actual gloss closer to the predetermined color density and the predetermined gloss, respectively.
10. The method according to claim 9 , further comprising:
adjusting the gloss by changing at least one of a fuser nip width and a fuser roller temperature; and
adjusting the color density by changing at least one of a toner lay-down amount, an exposure, an off-set voltage and a charger voltage.
11. The method according to claim 10 , further comprising measuring a pre-fused color toner patch transmission density to determine information about toner lay-down prior to the printed image being fused.
12. The method according to claim 11 , wherein the measured portion and the predicted portion are the same portion of the printed image.
13. The method according to claim 12 , wherein the measured portion and the predicted portion is a strip width of the printed image.
14. The method according to claim 9 , wherein the gloss meter and the color densitometer are integrally formed in a single unit.
15. A device for controlling an appearance of a printed image on a media substrate comprising:
a control unit allowing user input of a predicted gloss and a predicted color density of at least a predicted portion of the printed image, the predicted gloss and predicted color density being based on a digital bit map of the printed image and the media substrate;
a color densitometer for measuring an actual color density of at least a first measured portion of the printed image;
a gloss meter for measuring an actual gloss of at least a second measured portion of the printed image; and
wherein said control unit compares the actual color density with the predicted color density, compares the actual gloss with the predicted gloss, and adjusts the appearance as necessary to bring at least one of the actual color density and the actual gloss closer to the predicted color density and the predicted gloss, respectively.
16. The device according to claim 15 , wherein the first measured portion of the printed page is the same as the second measured portion of the printed page.
17. The device according to claim 15 , wherein:
said control unit adjusts the gloss by changing at least one of a fuser nip width and a fuser roller temperature; and
said control unit adjusts the color density by changing at least one of a toner lay-down amount, an exposure, an off-set voltage and a charger voltage.
18. The device according to claim 15 , further comprising a transmission densitometer for measuring a pre-fused toner transmission density to determine information about toner lay-down prior to the printed image being fused.
19. The device according to claim 15 , wherein said gloss meter and said color densitometer are integrally formed in a single unit.
20. A computer readable media for controlling an appearance of a printed image on a media substrate comprising:
a code segment for measuring an actual color density of at least a first measured portion of the printed image;
a code segment for measuring an actual gloss of at least a second measured portion of the printed image;
a code segment for comparing the actual color density with a predetermined value of color density;
a code segment for comparing the actual gloss with a predetermined value of gloss;
a code segment for adjusting the appearance as necessary to bring at least one of the actual color density and the actual gloss closer to the predetermined color density and the predetermined gloss, respectively; and
a code segment for determining the predetermined color density and the predetermined gloss by calculating a predicted gloss and a predicted color density of at least a predicted portion of the printed image, the calculation based on a digital bit map of the printed image and the media substrate.
21. The computer readable media according to claim 20 , further comprising a code segment for measuring a pre-fused color toner transmission density with a transmission densitometer to determine information about toner lay-down prior to the printed image being fused.