Image Reading Device And Correction Method For Image Reading Device

Patent metadata

Field	Value
Publication number	US-2016080583-A1
Application number	US-201414784891-A
Country	US
Kind code	A1
Filing date	Apr 15, 2014
Priority date	Apr 17, 2013
Publication date	Mar 17, 2016
Grant date	—

Abstract

An image forming apparatus 1 includes: a conveyance unit 40 that conveys a medium; a reading unit 50 that reads an image formed on the medium conveyed by the conveyance unit; a storage unit that stores data for specifying a color indicated by a reading result obtained from the reading unit 50 ; and a correction unit that corrects the data to match a color of the image and the color indicated by the reading result. The conveyance unit 40 conveys a color sample medium. Sa as a medium containing an image of a color region of a predetermined color, the reading unit 50 reads the image of the color region, and the correction unit corrects the data associated with the predetermined color in accordance with a reading result of the image of the color region obtained from the reading unit 50.

First claim

1 . An image reading device comprising: a conveyance unit that conveys a medium; a reading unit that reads an image formed on the medium conveyed by the conveyance unit; a storage unit that stores data for specifying a color indicated by a reading result obtained from the reading unit; and a correction unit that corrects the data to match a color of the image and the color indicated by the reading result,
wherein
the conveyance unit conveys a color sample medium as a medium containing an image of a color region of a predetermined color,
the reading unit reads the image of the color region, and
the correction unit corrects the data associated with the predetermined color in accordance with a reading result of the image of the color region obtained from the reading unit.

2 . The image reading device according to claim 1 , wherein
the color sample medium contains images of the color regions of a plurality of colors, and the correction unit corrects the data associated with the plurality of colors in accordance with reading results of the images of the color regions of the plurality of colors obtained from the reading unit.

3 . The image reading device according to claim 2 , further comprising a determination unit that determines reading timing for the respective images of the color regions of the plurality of colors contained in the color sample medium conveyed by the conveyance unit, wherein
the reading unit reads the respective images of the color regions of the plurality of colors in accordance with the reading timing determined by the determination unit.

4 . The image reading device according to claim 3 , wherein
the determination unit determines the reading timing in accordance with a conveyance amount of the color sample medium from a predetermined position on the upstream side of the reading unit in a conveyance direction of the medium conveyed by the conveyance unit.

5 . The image reading device according to claim 2 , wherein
the images of the color regions of the plurality of colors are formed on both surfaces of the color sample medium, and the conveyance unit includes a both-surface conveyance mechanism that conveys the medium such that the reading unit reads both the surfaces of the medium.

6 . The image reading device according to claim 1 , comprising a standby unit that puts the color sample medium on standby before the color sample medium is conveyed by the conveyance unit, wherein
the conveyance unit conveys the color sample medium from the standby unit.

7 . The image reading device according to claim 1 , comprising an evacuation unit that evacuates the color sample medium conveyed by the conveyance unit, wherein
the conveyance unit conveys the color sample medium read by the reading unit such that the color sample medium evacuates toward the evacuation unit.

8 . The image reading device according to claim 1 , wherein
the reading unit includes a predetermined number of three or more image pickup devices provided in a predetermined direction, and the storage unit stores reference data for each of a plurality of representative image pickup devices of a number smaller than the predetermined number of the predetermined number of image pickup devices, as representative image pickup devices selected from the predetermined number of image pickup devices, the reference data containing a plurality of reference values set individually as values selected within a range of a predetermined number of gradations from a minimum color value to a maximum color value and corresponding to a plurality of representative color values of a number smaller than the predetermined number of gradations, the correction unit includes
a first specification means that specifies an image pickup device corresponding to a correction target in the predetermined number of image pickup devices,
a second specification means that specifies a representative image pickup device corresponding to the image pickup device specified by the first specification means,
a third specification means that specifies a representative color value corresponding to a color value indicated by a reading result obtained from the image pickup device specified by the first specification means,
an acquisition means that acquires, from the storage unit, reference values corresponding to a combination of the representative image pickup device specified by the second specification means and the representative color value specified by the third specification means, and
a calculation means that calculates a correction value corresponding to a value indicated by the reading result obtained from the image pickup device specified by the first specification means in an interpolation process based on the reference values acquired by the acquisition means.

9 . The image reading device according to claim 8 , wherein
the second specification means specifies one representative image pickup device corresponding to the image pickup device specified by the first specification means when the image pickup device specified by the first specification means corresponds to any one of the plurality of representative image pickup devices, and specifies two representative image pickup devices close to the image pickup device specified by the first specification means when the image pickup device specified by the first specification means does not correspond to any one of the plurality of representative image pickup devices, and the third specification means specifies one representative color value corresponding to the color value indicated by a reading result obtained from the image pickup device specified by the first specification means when the color value indicated by this reading result corresponds to any one of the plurality of representative color values, and specifies two representative color values close to the color value indicated by the reading result obtained from the image pickup device specified by the first specification means when the color value indicated by this reading result does not correspond to any one of the representative color values.

10 . The image reading device according to claim 8 , wherein
the plurality of reference values are set based on values indicated by reading results obtained from the plurality of representative image pickup devices having read a color sample corresponding to the plurality of representative color values of the predetermined color.

11 . The image reading device according to claim 1 , wherein
the color sample medium has a thickness sufficient for preventing such a state that the other surface of the color sample medium is seen through one surface of the color sample read by the reading unit.

12 . A correction method for an image reading device which includes a conveyance unit that conveys a medium, a reading unit that reads an image formed on the medium conveyed by the conveyance unit, a storage unit that stores data for specifying a color indicated by a reading result obtained from the reading unit, and a correction unit that corrects the data to match a color of the image and the color indicated by the reading result,
the method characterized by comprising:
a step of allowing the conveyance unit to convey a color sample medium as a medium containing an image of a color region of a predetermined color,
a step of allowing the reading unit to read the image of the color region, and
a step of allowing the correction unit to correct the data associated with the predetermined color in accordance with a reading result of the image of the color region obtained from the reading unit.

13 . The image reading device according to claim 2 , com

Assignees

• Konica Minolta Inc

Inventors

• Mukaiyama Takashi

Classifications

• H04N1/4078

  using gradational references, e.g. grey-scale test pattern analysis · CPC title

• H04N1/00023 Primary

  Colour systems · CPC title

• H04N1/60

  Colour correction or control {(H04N1/54 takes precedence)} · CPC title

• H04N1/0032

  with a medium handling apparatus, e.g. a sheet sorter (handling thin or filamentary material, e.g. sheets B65H) · CPC title

• H04N1/00819

  Self-calibrating reading means · CPC title