Image forming apparatus, image forming method and image reading apparatus

1. An image forming apparatus comprising:

an image reading section that includes a paper table on which paper is to be positioned and that reads an image on paper positioned on the paper table to generate image data; and

an image forming section that forms an image on paper based on image data,

wherein the image forming section has a dimension correction mode in which a dimension correction image used to correct dimensions of an image is formed on paper, the dimension correction image including a plurality of marks at positions separated from each other on the paper,

wherein the image forming section includes

a computation unit that performs computation by using dimension correction image data to generate dimension correction data used to correct dimensions of an image, the dimension correction image data being obtained by the image reading section by reading, from paper on which the dimension correction image has been formed and which is positioned on the paper table, the dimension correction image, and

a memory that stores the dimension correction data generated by the computation unit,

wherein the image forming section corrects image data in accordance with the dimension correction data stored in the memory and forms an image based on the corrected image data, and

wherein the computation unit has a first computation mode in which first dimension correction data is generated on the basis of distances between the plurality of marks in data of a dimension correction image represented by the dimension correction image data and a second computation mode in which second dimension correction data is generated on the basis of distances between individual edges of paper and the corresponding marks in data of a dimension correction image represented by the dimension correction image data, the first dimension correction data being one kind of the dimension correction data, the second dimension correction data being one kind of the dimension correction data, and

wherein the image forming section corrects the image data by using the first dimension correction data in a first image formation mode and using the second dimension correction data in a second image formation mode.

2. The image forming apparatus according to claim 1 ,

wherein the memory includes a first memory and a second memory, and

wherein the computation unit generate both the first dimension correction data and the second dimension correction data, and stores the first dimension correction data in the first memory and stores the second dimension correction data in the second memory.

3. The image forming apparatus according to claim 2 , further comprising

an operation section that accepts an operation for switching between the first memory and the second memory,

wherein the image forming section corrects image data by using dimension correction data stored in a memory selected from among the first memory and the second memory as a result of the operation accepted by the operation section.

4. The image forming apparatus according to claim 2 , further comprising

an operation section that accepts an operation for switching between the first memory and the second memory,

wherein the image forming section corrects image data by using dimension correction data stored in a memory selected from among the first memory and the second memory as a result of the operation accepted by the operation section.

5. The image forming apparatus according to claim 1 , further comprising

an operation section that accepts an operation for switching between the first computation mode and the second computation mode,

wherein the computation unit generates the first dimension correction data or the second dimension correction data according to a computation mode selected from among the first computation mode and the second computation mode as a result of the operation accepted by the operation section.

6. The image forming apparatus according to claim 1 , wherein the image forming section corrects the image data by using the first dimension correction data if the image formation mode is a cutting planned mode in which the paper is cut after the image is formed on the paper.

7. The image forming apparatus according to claim 1 , wherein the image forming section corrects the image data by using the second dimension correction data if the image formation mode is a mode of forming images on both sides of the paper.

8. The image forming apparatus according to claim 1 , wherein the image forming section corrects the image data by using the first dimension correction data for a certain period if the image reading section is calibrated.

9. An image forming method comprising:

reading an image on paper positioned on a paper table to generate image data; and

forming on paper an image based on image data,

wherein in the forming, a dimension correction image used to correct dimensions of an image is formed on paper in a dimension correction mode, the dimension correction image including a plurality of marks at positions separated from each other on the paper,

wherein the forming includes

performing computation by using dimension correction image data to generate dimension correction data used to correct dimensions of an image, the dimension correction image data being obtained by reading, from paper on which the dimension correction image has been formed and which is positioned on the paper table, the dimension correction image, and

storing the generated dimension correction data in a memory,

wherein in the forming, image data is corrected in accordance with the dimension correction data stored in the memory and an image based on the corrected image data is formed, and

wherein in the performing computation, first dimension correction data is generated in a first computation mode on the basis of distances between the plurality of marks in data of a dimension correction image represented by thedimension correction image data and second dimension correction data is generated in a second computation mode on the basis o distances between individual edges of paper and the corresponding marks in data of a dimension correction image represented by the dimension correction image data, the first dimension correction data being one kind of the dimension correction data, the second dimension correction data being one kind of the dimension correction data,

wherein the forming an image on paper based on the image data corrects the image data by using one of the first dimension correction data and the second dimension correction data in accordance with an image formation mode, and

wherein the forming an image on paper based on the image data corrects the image data by using the first dimension correction data if the image formation mode is a cutting planned mode in which the paper is cut after the image is formed on the paper, and the image forming section corrects the image data by using the second dimension correction data if the image formation mode is a mode of forming images on both sides of the paper.

10. An image reading apparatus comprising:

an image reading section that includes a paper table on which paper is to be positioned and that reads an image on paper positioned on the paper table to generate image data;

an image forming section that forms an image on paper based on image data; and

a computation unit that performs computation by using dimension correction image data to generate dimension correction data used to correct dimensions of an image, the dimension correction image data being obtained by the image reading section by reading, from paper on which a dimension correction image has been formed and which is positioned on the paper table, the dimension correction image, the dimension correction image including a plurality of marks at positions separated from each other on the paper,

wherein the computation unit has a first computation mode in which first dimension correction data is generated on the basis of distances between the plurality of marks in data of a dimension correction image represented by the dimension correction image data and a second computation mode in which second dimension correction data is generated on the basis of distances between individual edges of paper and the corresponding marks in data of a dimension correction image represented by the dimension correction image data, the first dimension correction data being one kind of the dimension correction data, the second dimension correction data being one kind of the dimension correction data,

wherein the image forming section corrects the image data by using one of the first dimension correction data and the second dimension correction data in accordance with an image formation mode, and

wherein the image forming section corrects the image data by using the first dimension correction data if the image formation mode is a cutting planned mode in which the paper is cut after the image is formed on the paper, and the image forming section corrects the image data by using the second dimension correction data if the image formation mode is a mode of forming images on both sides of the paper.