US 10,207,495 B2Granted

Image forming apparatus, method for calculating actual distance of deviation, and computer program product storing same

AssigneeRicoh Company, Ltd.

InventorsKohta Aoyagi, Suguru Yokozawa, Masaya Kawarada, Nobuyuki Satoh

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Abstract

An image forming apparatus includes a conveyor to convey a recording medium; an image forming device including a recording head to form a test pattern including a first mark and a pair of second marks; an imaging device; and a processor. The processor includes a pattern forming unit to cause the image forming device to form one of the first and second marks and form the other after the conveyor conveys the recording medium by a predetermined conveyance amount, a position detector to detect positions of the first and second marks in the captured image, a ratio calculator to calculate a ratio between a distance between the second marks and deviation of the first mark in the captured image, and a distance calculator to calculate an actual distance of the deviation based on a theoretical distance between the second marks and the ratio.

Claims14

Dependent claims

An image forming apparatus comprising:

a conveyor to convey a recording medium;
an image forming device including at least one recording head to form, on the recording medium, a test pattern including at least one mark set including a first mark and a pair of second marks, the at least one recording head including a plurality of nozzles to discharge ink;
an imaging device to obtain a captured image of the test pattern;
and
at least one processor including:
a pattern forming unit configured to cause the image forming device to form one of the first mark and the pair of second marks on the recording medium and cause the image forming device to form the other of the first mark and the pair of second marks after the conveyor conveys the recording medium by a predetermined conveyance amount;
a position detector configured to detect a position of the first mark and a position of the pair of second marks in the captured image;
a ratio calculator configured to calculate a ratio between a distance between the pair of second marks in the captured image and an amount of deviation of the first mark in the captured image;
and
a distance calculator configured to calculate an actual distance of the deviation of the first mark based on a theoretical distance between the pair of second marks and the ratio.

7 more elements

Dependencies are inferred from the claim text.

Facts

Application: 15/808,813Filed 9 Nov 2017
Priority: JP 2016-22725222 Nov 2016
Published: US 2018/0141329 A124 May 2018
Granted: 19 Feb 2019
Term ends: Not estimatedThe source records don’t support an estimate.

Classification9 codes

B41J 2/04505
Control methods or devices therefor, e.g. driver circuits, control circuits: aiming at correcting alignment
B41J 2/04586
Control methods or devices therefor, e.g. driver circuits, control circuits: controlling heads of a type not covered by groups B41J2/04575 -…
B41J 2/2135
Print quality control characterised by dot disposition, e.g. for reducing white stripes or banding: alignment of dots
B41J 11/46
Controlling printing material conveyance for accurate alignment of the printing material with the printhead; Print registering: by marks or…