Image forming apparatus and image forming method

Patent metadata

Field	Value
Publication number	US-10493770-B2
Application number	US-201816135354-A
Country	US
Kind code	B2
Filing date	Sep 19, 2018
Priority date	Sep 18, 2014
Publication date	Dec 3, 2019
Grant date	Dec 3, 2019

Abstract

In an image forming apparatus (an ink jet printer 100 ), in a sub scanning direction, when an area in arrange of a nozzle at an end portion of a head ( 41 ) to a nozzle at a predetermined distance is set as a predetermined area, and a medium is transported in a certain amount by using the head ( 41 ), a scan portion, and a transport portion so as to form an image on medium sheet ( 10 ), the number of times of scanning for forming a dot array which is formed by using the nozzles included in the predetermined area is more than the number of times of the scanning for forming a dot array which does not use the nozzle in the predetermined area, and the number of times of the scanning for forming the dot array by using the nozzles included in the predetermined area is at least three times.

First claim

What is claimed is:

1. An image forming apparatus comprising:
a head including a plurality of nozzles which discharge a liquid with respect to a medium, the plurality of nozzles being configured with a first plurality of nozzles and a second plurality of nozzles;
a scan mechanism configured to relatively scan the head in a main scanning direction with respect to the medium;
a transport mechanism configured to relatively transport the medium in a sub scanning direction intersecting the main scanning direction with respect to the head;
a memory configured to store computer-readable instructions; and
a processor configured to execute the computer-readable instructions so as to:
alternately cause the scan mechanism to scan and the transport mechanism to transport so as to form an image on the medium by the discharged liquid; and
create image data corresponding to a first region on the medium formed by a first recording and a second region on the medium formed by a second recording when the processor is configured to maintain a movement amount of the transport mechanism as a constant value,

wherein the first region and the second region are alternately arranged on the medium in the sub scanning direction,
the first plurality of nozzles that are used in the first recording are sandwiched by the second plurality of nozzles that are used in the second recording, and
a first number of scan passes of the head in the first recording is larger than a second number of scan passes of the head in the second recording.

2. The image forming apparatus according to claim 1 ,
wherein a first length of the first region on the medium in the sub scanning direction is shorter than a second length of the second region on the medium in the sub scanning direction.

3. The image forming apparatus according to claim 1 ,
wherein a first length of the first region on the medium in the sub scanning direction is equal to a second length of the second region on the medium in the sub scanning direction.

4. The image forming apparatus according to claim 1 ,
wherein a first average nozzle use ratio of the first plurality of nozzles used in the first recording is smaller than a second average nozzle use ratio of the second plurality of nozzles used in the second recording.

Assignees

• Seiko Epson Corp

Inventors

• Hoshii Jun

Classifications

• B41J2/51

  serial printer type · CPC title

• B41J2/2132 Primary

  Print quality control characterised by dot disposition, e.g. for reducing white stripes or banding (methods for local corrections by dot omission, image edge enhancement, or multi-pass mask selection G06K15/102; colour conversion H04N1/40) · CPC title

• B41J2/04503

  aiming at compensating carriage speed · CPC title

• B41J2/135

  Nozzles · CPC title

• B41J2/5056

  using dot arrays providing selective dot disposition modes, e.g. different dot densities for high speed and high-quality printing, array line selections for multi-pass printing, or dot shifts for character inclination (B41J2/2132 takes precedence) · CPC title