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US 8,911,055 B2Granted
Dot position measurement method and dot position measurement apparatus
AssigneeFUJIFILM Corporation
InventorYoshirou Yamazaki
Life of this patent
Estimating the term…
Abstract
A dot position measurement method and a dot position measurement apparatus provide a plurality of common line blocks and averaging measurement values of positions of lines in each common line blocks when correcting the measurement positions in each line block by taking a common line block (reference line block) as a reference position, and it is possible to reduce effects of random positional variation in a main scanning direction of an image reading apparatus.
Claims10
A dot position measurement method, comprising:
- a line pattern forming step of forming a measurement line pattern including a plurality of lines of rows of dots corresponding to a plurality of recording elements arranged in a first direction of a recording head respectively, on a recording medium, while causing relative movement between the recording head and the recording medium in a second direction perpendicular to the first direction, the measurement line pattern including a plurality of line blocks respectively including a group of the lines recorded by the recording elements spaced at a prescribed interval in the first direction, and a plurality of common line blocks respectively including the lines recorded by the recording elements which are same as the recording elements recording the lines included in the plurality of line blocks respectively;
- a reading step of reading an image of the measurement line pattern formed on the recording medium in the line pattern forming step, by an image reading apparatus;
- a line position measurement step of measuring positions of the lines included in the plurality of line blocks and the plurality of common line blocks, from the image of the measurement line pattern read by the image reading apparatus;
- an averaging step of determining average values with respect to the recording elements, each of the average values being an average value of measurement values of positions of the lines recorded by a same one of the recording elements and included in a same one of the plurality of common line blocks;
- and
- a line position correction step of correcting the measurement values of the positions of the lines according to the average values.
3 more elements
A dot position measurement apparatus comprising:
- an image reading apparatus reading an image of a measurement line pattern including a plurality of lines of rows of dots which are formed on a recording medium by an image forming apparatus and which corresponds to respective recording elements of a recording head arranged in a first direction while relative movement between the recording head and the recording medium is caused in a second direction perpendicular to the first direction, the measurement line pattern including a plurality of line blocks respectively including a group of the lines recorded by the recording elements spaced at a prescribed interval in the first direction, and a plurality of common line blocks respectively including the lines recorded by the recording elements which are same as the recording elements recording the lines included in the plurality of line blocks respectively;
- a line position measurement device which measures positions of the lines included in the plurality of line blocks and the plurality of common line blocks, from the image of the measurement line pattern read by the image reading apparatus;
- an averaging device which determines average values with respect to the recording elements, each of the average values being an average value of measurement values of positions of the lines recorded by a same one of the recording elements and included in a same one of the plurality of common line blocks;
- and
- a line position correction device which corrects the measurement values of the positions of the lines according to the average values.
2 more elements
Dependencies are inferred from the claim text.