System and method for halftone printing in a three-dimensional object printer

Patent metadata

Field	Value
Publication number	US-9286554-B1
Application number	US-201514676439-A
Country	US
Kind code	B1
Filing date	Apr 1, 2015
Priority date	Apr 1, 2015
Publication date	Mar 15, 2016
Grant date	Mar 15, 2016

Abstract

A method of forming halftone printed images in a three-dimensional printer includes generating halftone coverage data for a region of an image receiving surface including at least one color marking agent and a color neutral marking agent. The method further includes generating halftone image data with reference to the halftone coverage data and operating a plurality of ejectors to form a printed halftone image having a uniform thickness. A first pixel location receives a first color marking agent and at least a second pixel location receives the color neutral marking agent.

First claim

What is claimed:

1. A method of operating a three-dimensional object printer comprising:
receiving with a controller contone image data;
generating with the controller relative halftone coverage data corresponding to proportions of each marking agent in a plurality of marking agents that form a halftone pattern on an image receiving surface that corresponds to the contone image data, the plurality of marking agents including at least a first color marking agent and a color neutral marking agent;
generating with the controller halftone image data corresponding to each pixel location in a plurality of pixel locations on a region of the image receiving surface with reference to the relative halftone coverage data; and
operating with the controller a plurality of ejectors in a print zone of the printer to eject one marking agent in the plurality of marking agents onto each pixel location in the plurality of pixel locations in the region of the image receiving surface with reference to the halftone image data to form a printed halftone image having a uniform thickness in the region of the image receiving surface, at least a first pixel location receiving the first color marking agent and at least a second pixel location receiving the color neutral marking agent.

2. The method of claim 1 , the generation of the halftone image data further comprising:
generating with the controller the relative halftone coverage data including a first proportion corresponding to an amount of the first color marking agent color to produce the halftone pattern corresponding to the contone image data;
generating with the controller the relative halftone coverage data including a second proportion corresponding to an amount of the color neutral marking agent with reference to a proportion of the plurality of pixel locations in the region of the image receiving surface that does not correspond to any color marking agent in the plurality of marking agents; and
generate randomized halftone image data with reference to the first proportion and the second proportion to cover each pixel location in the plurality of pixel locations with one of the plurality of marking agents.

3. The method of claim 2 , the generation of the randomized halftone image data further comprising:
generating with the controller a random number in a predetermined range; and
generating with the controller the first pixel location in the halftone image data corresponding to the first marking agent in response to the random number corresponding to the first proportion within the predetermined range.

4. The method of claim 1 , the generation of the relative halftone coverage data and operation of the plurality of ejectors further comprising:
generating with the controller the relative halftone coverage data corresponding to proportions of a plurality of marking agents including a plurality of color marking agents and the color neutral marking agent to form the halftone pattern corresponding to the contone image data; and
operating with the controller the plurality of ejectors to eject one marking agent in the plurality of marking agents onto each pixel location in the plurality of pixel locations in the region of the image receiving surface with reference to the halftone image data to form the printed halftone image having the uniform thickness in the region of the image receiving surface, at least a third pixel location in the plurality of pixel locations receiving a second color marking agent in the plurality of color marking agents.

5. The method of claim 4 , the generation of the randomized halftone image data further comprising:
assign with the controller a portion of a predetermined numeric range to each color marking agent in the plurality of color marking agents with reference to a size of each proportion in the plurality of proportions for the plurality of color marking agents;
assigning with the controller another portion of the predetermined numeric range to the color neutral marking agent corresponding to a portion of the predetermined numeric range that is not assigned to any of the plurality of color marking agents;
generating with the controller a random value within the predetermined numeric range;
identifying with the controller one of the plurality of color marking agents or the color neutral marking agent in response to the random value being within a corresponding portion of the predetermined numeric range assigned to the identified marking agent; and
generating with the controller the halftone image data with the identified marking agent in one pixel location in the plurality of pixel locations.

6. The method of claim 1 , the operation of the plurality of ejectors further comprising:
operating with the controller the plurality of ejectors to form the halftone printed image on a surface of a support member in the three-dimensional object printer; and
operating with the controller another plurality of ejectors to form a layer of a build material over the halftone printed image.

7. The method of claim 1 , the operation of the plurality of ejectors further comprising:
operating with the controller the plurality of ejectors to form the halftone printed image on a surface of a three-dimensional printed object positioned in the print zone.

8. A three-dimensional object printer comprising:
a plurality of ejectors configured to eject drops of at least a first color marking agent and a color neutral marking agent onto an image receiving surface in a print zone;
a memory configured to store contone image data; and
a controller operatively connected to the plurality of ejectors and the memory, the controller being configured to:
receive the contone image data from the memory;
generate relative halftone coverage data corresponding to proportions of each marking agent in the plurality of marking agents that form a halftone pattern on the image receiving surface that corresponds to the contone image data;
generate halftone image data corresponding to each pixel location in a plurality of pixel locations on a region of the image receiving surface with reference to the relative halftone coverage data; and
operate the plurality of ejectors to eject one marking agent in the plurality of marking agents onto each pixel location in the plurality of pixel locations in the region of the image receiving surface with reference to the halftone image data to form a printed halftone image having a uniform thickness in the region of the image receiving surface, at least a first pixel location receiving the first color marking agent and at least a second pixel location receiving the color neutral marking agent.

9. The printer of claim 8 , the controller being further configured to:
generate the relative halftone coverage data including a first proportion corresponding to an amount of the first color marking agent color to produce the halftone pattern corresponding to the contone image data;
generate the relative halftone coverage data including a second proportion corresponding to an amount of the color neutral marking agent with reference to a proportion of the plurality of pixel locations in the region of the image receiving surface that does not correspond to any color marking agent in the plurality of marking agents; and
generate randomized halftone image data with reference to the first proportion and the second proportion to cover each pixel location in the plurality of pixel locations with one of the plurality of marking agents.

10. The printer of claim 9 , the controller being further configured to:
generate a random number in a predetermined range; and
generate the first pixel location in the halftone image data corresponding to the first marki

Assignees

• Xerox Corp

Inventors

• Maltz Martin S
• Triplett Roger L

Classifications

• B33Y10/00

  Processes of additive manufacturing · CPC title

• B33Y50/02

  for controlling or regulating additive manufacturing processes · CPC title

• G06K15/1881 Primary

  Halftoning (halftoning of still images in general H04N1/405, H04N1/52) · CPC title

• H04N1/52 Primary

  Circuits or arrangements for halftone screening · CPC title

• B33Y50/00

  Data acquisition or data processing for additive manufacturing · CPC title