JP2003260821A - Imaging apparatus, imaging system and imaging method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an imaging apparatus which can obtain good images as images after being attached by reducing a color difference of attached parts of a plurality of dividedly printed papers. <P>SOLUTION: When image data is sent from a host apparatus 2, the data is received via a communication interface 22 and analyzed by a PDL analysis part 23 to generate plotting data. When a dividing number is designated from the host apparatus 2, a plotting processor 24 divides the image to partial images of a page size whereby imaging is to be actually carried out. For two partial images to be formed in papers attached in a direction in which a density irregularity is present in each partial image, it is judged that either one of the images is to be subjected to a rotating process. The partial image judged to be subjected to the rotating process is rotated by 180°. Thereafter, image data is plot developed into a storage part 25 and sent via an engine control unit 26 to a printing engine 27, whereby the partial image is formed to each paper. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique used when an image is formed by dividing one image into a plurality of sheets in an image forming apparatus.

[0002]

2. Description of the Related Art Conventionally, as one of the functions of an image forming apparatus, there is a division printing function of dividing an image into a plurality of sheets and printing the divided images. In this division printing, an image larger than a sheet usable in the image forming apparatus is divided into sheet sizes to form an image. After that, the user sticks the sheets on which images have been formed to obtain a recorded product of a desired size. For example, it is used to create posters, banners, etc., and is sometimes called poster printing.

FIG. 14 is an illustration of an example of divided printing. In the case of forming an image including a character string of "newly opened" as shown in FIG. 14A, it cannot be formed on a commonly used sheet. In such a case, for example, as shown in FIG. 14B, a plurality of partial images (here, three partial images) are divided, and each partial image is formed on a sheet. Then, the papers on which the partial images are formed are appropriately laminated as shown in FIG. 14C, whereby the content of the original image can be reproduced.

On the other hand, one of the image forming methods in the image forming apparatus is an electrophotographic system. In an image forming apparatus using electrophotographic technology, a latent image is formed by irradiating light on a photoconductor based on the image, and the latent image is developed with toner. The image is formed by transferring and fixing the toner on the paper at the fixing unit. In the fixing unit, heat is applied to the paper and the toner to melt the toner and fix the toner on the paper.

As described above, in the electrophotographic image forming apparatus, heat is applied to fix the toner on the paper.
In the fixing unit, heat is released together with the paper by transporting the paper, and the temperature applied to the paper in the paper transport direction decreases. For this reason, it is known that fixing is not constant and the density generally decreases in the paper transport direction.

FIG. 15 is an illustration of an example of an image formed when division printing is performed in a conventional image forming apparatus. In FIG. 15, the shading is shown by the amount of hatching. As described above, in the image forming apparatus of the electrophotographic system, the density changes in the sheet conveying direction.
In the background of uniform density as shown in (A), the character "A" is displayed.
Even if the image is drawn, if an image is actually formed, the image shown in FIG.
As shown in (B), the density gradually decreases in the paper transport direction.

For example, as shown in FIG. 15 (C), the character "ai" is divided into two sheets by divided printing and printed, and when the sheets are pasted together, as shown in FIG. Steps of light and shade will occur. Even if the density change in one sheet is small and inconspicuous, there is a problem that when the high density part and the light density part are adjacent to each other by laminating, the color difference of the bonded part becomes conspicuous. Therefore, the image after being bonded was not good.

In order to solve this problem, it is conceivable to suppress the temperature drop in the fixing section by increasing the heat capacity of the fixing section in the image forming apparatus or increasing the heat source. However, the cost is high and the durability is also a problem.

[0009]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and reduces the color difference between the pasted portions of a plurality of sheets of divided printing, which is excellent as an image after pasting. An image forming apparatus capable of obtaining an image,
It is an object of the present invention to provide an image forming system and an image forming method.

[0010]

According to the present invention, when one image is divided into a plurality of sheets and formed, it is determined whether or not a rotation process is performed in consideration of the positions of pasting the sheets. Then
The partial image determined to be rotated is rotated by 180 degrees as compared with the other partial images, and each partial image is formed on a sheet.
For example, when density unevenness occurs in the paper transport direction and the densities of the leading and trailing edges of the paper are different, one of the two partial images formed on the two sheets of paper to be bonded is rotated by 180 degrees and formed. . As a result, when the sheets are pasted together, the leading edges or the trailing edges of the sheets are pasted together, and the areas with high density or the areas with light density are adjacent to each other, and the uneven density is not noticeable. Images can be obtained.

When images are formed on a plurality of sheets at once, the density changes depending on the order of image formation. In such a case, for each partial image, it is determined whether or not the rotation process is performed, and whether or not the image forming order is further changed, and the partial images are rotated and the image forming order is changed according to the determination result. It is good to configure. Further, for example, the sheets may be attached one-dimensionally in order, and in addition, they may be attached two-dimensionally. In such a case, the division mode may be determined from the size of the image and the size of the sheet, and whether or not to perform the rotation process may be determined according to the position of the sheet after the bonding. Of course, when there is no image in the portion where the sheets are stuck together, the image formation can be performed without performing the rotation process.

Further, according to the present invention, when one image is divided into a plurality of sheets and is formed, the partial image to be formed on each sheet is considered to be either vertically long or horizontally long in consideration of the bonding position of each sheet. The paper is selected, and each partial image is formed on the selected paper. At this time, the selection of the paper can be performed based on the direction in which the uneven density occurs. For example, if the dark and light unevenness is noticeable when the long sides of horizontally long sheets (short sides parallel to the paper conveyance direction) are stuck together, select vertically long sheets (long sides parallel to the paper conveyance direction). Then, an image is formed.
As a result, the same density change occurs between the adjacent sheets on the side where the sheets are pasted together, and uneven density in the pasted portion is less noticeable, and a good pasted image can be obtained.

Also in this case, the rotation processing is appropriately performed on the partial images according to the position of the sheets after being pasted together, which corresponds to, for example, two-dimensional pasting. be able to. Further, if there is no image in the portion where the sheets are stuck together, the rotation processing may not be performed.

[0014]

FIG. 1 is a system configuration diagram of an example of an image forming apparatus showing a first embodiment of the present invention, FIG.
FIG. 3 is a schematic configuration diagram of an example of an image forming apparatus. In the figure, 1 is an image forming apparatus, 2 is a host device, 11 is a toner unit, 12 is a drum unit, 13 is an intermediate transfer member,
14 is a fixing unit, 15 is paper, 21 is a printer controller, 22 is a communication interface, 23 is a PDL analysis section, 24 is a drawing processing section, 25 is a storage section, 26 is an engine control section, and 27 is a print engine. here,
The image forming apparatus 1 is connected to the host apparatus 2 and forms an image on a sheet according to the image data sent from the host apparatus 2.

The image forming apparatus 1 in this example is an apparatus for forming a color image. For example, as shown in FIG. 2, a toner unit 11, a drum unit 12, an intermediate transfer member 1 are provided.
3, the fixing unit 14 and the like. The toner unit 11 is provided with four color toners of cyan (C), magenta (M), yellow (Y), and black (K), and a latent image formed on the drum unit 12 is formed one by one. develop. Drum unit 12
Has a surface formed of a photoconductor, and a latent image is written by being irradiated with light corresponding to an image to be formed from a light source (not shown). The latent image is the toner unit 1
1 is developed. The toner image on the developed drum unit 12 is transferred to the intermediate transfer body 13. After the toner images of four colors have been transferred, the transferred toner images are transferred again onto the paper 15. The fixing unit 14 melts and fixes the toner image transferred onto the paper 15 by heating.

When forming an image in the image forming apparatus 1 having such a configuration, first, the toner unit 11 is rotated, and the cyan component latent image formed on the drum unit 12 is developed using cyan toner. . The cyan component toner image generated on the drum unit 12 is transferred to the intermediate transfer member 13. Similarly, a toner image of a magenta component is generated on the drum unit 12, and the intermediate transfer member 1
3 Transfer to above. Similarly, the yellow component and the black component are transferred to the intermediate transfer body 13. Thus, the intermediate transfer member 1
Images of 4 colors are combined in 3. After the images of four colors are generated on the intermediate transfer body 13, the paper 15 is conveyed, the image is transferred from the intermediate transfer body 13 to the paper 15, the fixing unit 14 performs a fixing process, and then the paper is discharged. At this time, the paper 15 is conveyed in the direction of the arrow in the figure. In the case of a printer that outputs in units of two pages, toner images for two pages are generated on the intermediate transfer body 12, two sheets are continuously conveyed at one time, and the toner images are transferred to the two sheets. Then, the fixing unit 13 performs a fixing process and then discharges the sheet.

Although a four-cycle type color image forming apparatus is shown in FIG. 2, the present invention is not limited to this and may be, for example, a two-cycle type or tandem type image forming apparatus, or an intermediate transfer member. A configuration not using 13 may be used. Further, the image forming apparatus is not limited to color and may be a monochrome image forming apparatus.

Next, the system configuration of the image forming apparatus will be described with reference to FIG. The image forming apparatus 1 has a printer controller 21 and a print engine 27. The print engine 27 has a configuration (not shown) for forming a latent image on the drum unit 12 in accordance with an image sent from the print controller 21, in addition to the configuration shown in FIG.

The printer controller 21 controls each unit in the image forming apparatus 1 including the print engine 27, receives image data sent from an external device such as the host device 2, and forms an image that can be formed by the print engine 27. Generate and output drawing. In this example, the printer controller 21, the communication interface 22, the PDL analysis unit 2
3, drawing processing unit 24, storage unit 25, engine control unit 26
And so on.

The communication interface 22 is the host device 2.
And the image data sent from the host device 2 is received. The PDL analysis unit 23 analyzes the image data received from the host device 2. Drawing processing unit 2
In accordance with the analysis result of the PDL analysis unit 23, the image data 4 is drawn by the print engine 27 and stored in the storage unit 25. At this time, in the case of a color image, images of four colors (yellow, magenta, cyan, black) are drawn for each page, and in the case of monochrome, only one color (black) is drawn. The engine control unit 26
The image drawn in the storage unit 25 is transferred to the print engine 27, and the image is formed on the paper.

Next, the operation of the printer controller 21, particularly an example of the operation during division printing will be described. Figure 3
6 is a flow chart showing a first example of an operation at the time of division printing in the first embodiment of the present invention. When the image data is transmitted from the host apparatus 2, the communication interface 22 of the image forming apparatus 1 receives the image data, and the PDL
The analysis unit 23 analyzes the image data and creates drawing data in S31. Here, when performing the divided printing, it is assumed that the image data forming an image larger than the size of the paper and the number of divisions at that time are specified from the host device 2.

In S32, it is determined whether or not the number of divisions is designated by the host device 2. If the number of divisions is not specified, normal image formation is performed and S36 is performed.
The drawing processing unit 24 performs the drawing process of the image data in FIG. Since the image data is drawn in the storage unit 25,
After the image data for at least one page or one color for one page is drawn, the engine control unit 26 reads the image data from the storage unit 25 and transfers the image data to the print engine 27 to form an image.

If the number of divisions is specified, S32
From S33, the page size (paper size) at which the image to be formed is actually formed in S33.
The process of dividing the image into partial images is performed. This division processing is performed here in the state of drawing data. When the partial image to be formed for each page (paper) can be divided, it is determined in S34 whether each partial image is rotated. At this time, the determination is made in consideration of the bonding position of the sheets after the image formation. For example, when uneven density occurs in the paper transport direction, or when the bonding position comes to the rear end of the paper transport direction, a density difference occurs at the bonding portion,
Color difference may be noticeable. Therefore, in such a case, of the partial images formed on the two sheets of paper to be bonded,
It is determined that one of them is a partial image to be rotated.

Then, the partial image which is determined to be rotated in S34 is rotated by 180 degrees as compared with the other partial images in S35. The process of S35 is skipped for the partial image which is determined not to be rotated. The image may need to be rotated 90 degrees or 270 degrees depending on the orientation of the paper used. In such a case, the partial image determined not to be rotated is 90 degrees or 270 degrees.
The rotation processing is performed by 180 degrees, and the partial image determined to be rotated is further rotated by 180 degrees and rotated by 270 degrees or 90 degrees. Thereafter, in S36, the image data drawing process and the subsequent image forming process are performed.

FIG. 4 is an explanatory diagram of a first specific example of the divided printing result according to the first embodiment of the present invention. Here, as shown in FIG. 4A, the case where a long image having the long side of the paper as the width is formed is shown. In addition, four sheets are used (divided into four), and the long sides of the respective sheets are bonded together. Further, it is assumed that the conveyance direction is the short side direction of the paper (the long side is before and after the conveyance direction), and uneven density occurs in the conveyance direction.

In such a case, the image shown in FIG. 4 (A) is divided into four parts, and four partial images are formed on the paper. At this time, when image formation is performed without performing rotation processing as in the conventional case, images are formed on four sheets of paper as shown in FIG. 4B, and when they are stuck together, as shown in FIG. The light and shade unevenness is noticeable in the pasted part. On the other hand, in the present invention, it is determined that the rotation processing is performed on the second and fourth images of the four divided images, and the rotation processing of 180 degrees is performed. As a result, an image is formed on the four sheets as shown in FIG. By inverting and pasting the top and bottom of the second and fourth sheets,
A long image as shown in (E) is obtained. Figure 4 (E)
As can be seen by referring to, there is no density difference in the bonded portion. For this reason, the uneven density that has occurred in the past in the pasted portion is less noticeable, and a good image can be obtained.

In this example, the second and fourth partial images are determined as the target of the rotation processing, but the present invention is not limited to this.
The first and third images may be determined as the target of the rotation processing. In this case as well, similarly, the unevenness of light and shade in the bonded portion becomes inconspicuous and a good image can be obtained.

FIG. 5 is an explanatory diagram of a second specific example of the division printing result according to the first embodiment of the present invention. Here, a case is shown in which an image as shown in FIG. 5 (A) is instructed to be divided into three vertically and horizontally as shown in FIG. 5 (B). In this specific example as well, the conveyance direction of the paper is assumed to be the short side direction of the paper (the long side is the front or rear of the conveyance direction or one of the arrows in the figure), and uneven density may occur in the conveyance direction. .

In such a case, the image shown in FIG. 5 (A) is divided into nine parts as shown in FIG. 5 (B), and nine partial images are formed on the paper. It is determined whether or not the rotation process is performed according to the position of the sheets after the matching. For example, a page group in contact with a side (short side) parallel to the transport direction is a page group in a row, and a page group in contact with a side (long side) perpendicular to the transport direction is a page group in a column. To do. Whether or not the page should be rotated 180 degrees with respect to the transport direction can be determined by whether or not the page belongs to the page group of the same row. For example, if the page group in the odd-numbered row is not rotated, the page group in the even-numbered row is determined to be the object of rotation. Specifically, it is determined that the rotation process is performed on the partial image included in the page group of the second row shown as “rotation” in FIG. 5C, and the partial image is rotated by 180 degrees as compared with other partial images. Perform processing. On the contrary, when the page group of the odd-numbered rows is to be rotated, it may be determined that the page group of the even-numbered rows is not rotated.

For example, in the case of forming partial images sequentially in the column direction, "a", "i", "u", and "a" shown in FIG.
Partial images are formed in the order of "Eh" and so on. At this time,
When it is determined that the rotation processing is performed on the partial images included in the page group of even rows, the rotation processing of 180 degrees is performed on the partial images including “i”, “o”, and “ku”. As a result, partial images are sequentially formed on the paper as shown in FIG. Second "I", 5
The second "O" and the eighth "Ku" are images rotated by 180 degrees.

An image as shown in FIG. 5A is obtained by pasting these nine sheets together. Similar to the first specific example, between the three images in the column direction, the image formed on the intermediate sheet is rotated by 180 degrees,
The appearance of light and shade unevenness in the pasted part is suppressed.
Further, in the row direction, since the density change similarly occurs between the two bonded sheets, it is difficult to visually recognize the density change. Therefore, a good bonded image can be obtained. On the contrary, in this example, it is preferable not to perform the rotation process on the images formed on the sheets to be laminated in the row direction.

In this example, the partial image included in the page group of even rows is determined as the target of the rotation processing, but the present invention is not limited to this, and the partial image included in the page group of odd rows is rotated as described above. May be determined as the target of.
In this case as well, similarly, the unevenness of light and shade in the bonded portion becomes inconspicuous and a good image can be obtained.

FIG. 6 is a flow chart showing a second example of the operation at the time of division printing in the first embodiment of the present invention. In this operation example, the image data received from the host device 2 is originally a small image, and an enlargement process is performed on the image data to divide an image larger than a sheet into a plurality of sheets to be formed.

When the image data is transmitted from the host apparatus 2, the communication interface 22 of the image forming apparatus 1 receives the image data, the PDL analysis unit 23 analyzes the image data, and drawing data is created in S41.
Here, when performing division printing, it is assumed that the enlargement ratio, the size after enlargement, and the like, and the number of divisions at that time are specified from the host device 2.

In S42, it is determined whether the number of divisions is designated by the host device 2. If the number of divisions is not specified, normal image formation is performed, and S47 is performed.
The drawing processing unit 24 performs the drawing process of the image data in FIG. The subsequent processing is the same as that of the above-mentioned first operation example.

If the number of divisions is specified, S42
From S43, the drawing data is enlarged in S43 so as to have the designated enlargement ratio or the enlarged size. Next, in S44, the drawing data after the enlargement processing is divided into partial images of a page size (paper size) on which an image is actually formed. After the partial images to be formed on each page (paper) can be divided, it is determined in S45 whether or not the rotation process is performed for each partial image. The determination method is the same as that of the first operation example described above.

Then, the partial image which is determined to be rotated in S45 is subjected to a rotation process of 180 degrees as compared with the other partial images in S46. The process of S46 is skipped for the partial image which is determined not to be rotated. The image may need to be rotated 90 degrees or 270 degrees depending on the orientation of the paper used. In such a case, the partial image determined not to be rotated is 90 degrees or 270 degrees.
The rotation processing is performed by 180 degrees, and the partial image determined to be rotated is further rotated by 180 degrees and rotated by 270 degrees or 90 degrees. Then, in S47, the image data drawing process and the subsequent image forming process are performed.

In this way, even if the image data received from the host device 2 is small, it is possible to provide a large image formed by bonding a plurality of sheets of paper with good image quality. In this second operation example, only the enlargement processing is added to the above-mentioned first operation example, and therefore the specific example is the same as the above-mentioned first operation example.

FIG. 7 is a flow chart showing a third example of the operation at the time of division printing in the first embodiment of the invention. In FIG. 7, the processing of S51 to S53 is the same processing as S31 to S33 in FIG.
Since the processing of 7 is the same processing as S34 to S36 in FIG. 3, duplicated description will be omitted.

In the third operation example, processing in the case where a partial image to be a blank page is included in the divided partial images is added to the above first operation example.
It is clear that no image is formed on a blank page and uneven density does not occur. Therefore, it is not necessary to determine whether or not to perform the rotation process for the blank page and the actual rotation process, and in the case of the blank page, these processes can be skipped.

Specifically, in the case of division printing, S53
In step S54, it is determined whether or not the page is a blank page for each partial image after performing a process of dividing each partial image of the page size (paper size) in which the image is actually formed. If it is determined that the page is a blank page, it is determined whether the rotation process in S55 is performed and S
The rotation process in 56 may be skipped and the drawing process in S57 may be performed as it is. In this case, since there is no image to be drawn, the paper is substantially discharged.
Of course, the blank page may not be processed after the drawing, and the user may be prompted to paste a blank page.

Although a blank page is determined here, if there is no image to be formed, for example, in the pasted portion or the pasted portion and its periphery (in other words, if it is a blank sheet portion), the same is done. There is no need to perform rotation processing. The images here are characters and figures,
In addition to objects such as photographs, the background is an image when coloring other than the paper color. For example, when the background color is white (color of paper) in the specific examples shown in FIGS. 4 and 5, the toner of any color is not used in the pasted portion, and uneven density does not occur. Therefore, in such a case, similarly to the blank page described above, the image forming process can be performed without performing the rotation process.

By not performing the rotation process when there is a blank page or when there is no image in the pasted portion as described above, it is possible to eliminate the time required for the rotation process and perform high-speed printing.

FIG. 8 is a flow chart showing a fourth example of the operation at the time of division printing in the first embodiment of the invention. In FIG. 8, the processing of S61 to S63 is the same processing as S31 to S33 in FIG. 3, and the processing of S67 is the same processing as S36 in FIG. 3, so redundant description will be omitted.

The fourth operation example is an operation example corresponding to the case where the print engine 27 forms an image in units of a plurality of sheets, and particularly in the case of two sheets in unit.
The case where images can be continuously formed on a single sheet is shown. For example, in an image forming apparatus compatible with A3 size, A
Images can be continuously formed on two sheets of four sizes. In such a case, the density change gradually occurs over the two sheets. That is, the leading edge of the first sheet is thick, the trailing edge of the first sheet and the leading edge of the second sheet are medium density, and the trailing edge of the second sheet is thin. Therefore, the two sheets on which images are continuously formed may be pasted as they are, and no color difference due to unevenness in light and shade occurs at the pasted portion. But,
Between the rear end portion of the second sheet and the front end portion of the third sheet, if they are adhered as they are, uneven density becomes noticeable and the image quality deteriorates.

When the image formation is performed in units of a plurality of sheets in this way, it may be determined whether or not the rotation process is performed for each unit. Also, in order to maintain the density continuity in the unit where the rotation processing is performed, in the united part of the paper in the unit,
It is necessary to change the order of forming the partial images. This will be apparent with reference to the specific examples described below.

In the fourth operation example shown in FIG. 8, after division processing is performed for each partial image of the page size (paper size) on which image formation is actually performed in S63 when performing division printing, at S64. It is determined whether or not to rotate the partial image in units of a plurality of sheets (here, two sheets). S
It is determined that the rotation processing is performed in 64 (2 in this case).
The partial image of (3) is subjected to a rotation process of 180 degrees with respect to the partial images of other units in S65, and then in S66, a process of changing the image forming order of the partial images in the unit is performed. To do. S64
For partial images in the unit determined not to be rotated in step S6, steps S65 and S66 are skipped. Then, in S67, the drawing process and the subsequent processes may be performed for each partial image.

In this way, even when divided printing is performed by the image forming apparatus equipped with the print engine 27 that forms images simultaneously on a plurality of sheets as a unit, it is possible to obtain a combined image with good image quality. You can

FIG. 9 is an explanatory diagram of a third specific example of the divided printing result according to the first embodiment of the present invention. Here, similar to FIG. 4, a case where a long image having the long side of the paper as the width is formed as shown in FIG. 9A is shown. In addition, four sheets are used (divided into four), and the long sides of the respective sheets are bonded together. Further, it is assumed that the conveyance direction is the short side direction of the paper (long side is before and after the conveyance direction), and image formation is performed simultaneously in units of two sheets. Then, it is assumed that shading unevenness occurs in the transport direction.

Here, it is determined that the odd-numbered units are the objects of the rotation processing. That is, it is determined that the first two partial images of the image shown in FIG. 9A divided into four by the broken line in the figure are the target of the rotation processing. Then, each of these partial images is rotated by 180 degrees. When the image formation is performed in this order, the image as shown in FIG. 9B is formed on each sheet. When it is pasted as it is, it becomes as shown in FIG. 9C.
Color differences due to uneven density occur between the second sheet and between the second and third sheets.

Therefore, as shown in FIG. 9D, the image forming order of the two rotated partial images is exchanged.
This makes it possible to obtain a good bonded image without causing a color difference due to unevenness in light and shade as shown in FIG. As described above, for a plurality of partial images in the unit determined to be rotated, the order of image formation is changed after the rotation processing of each partial image, so that a good sticking can be achieved without being affected by uneven density. A combined image can be obtained.

In this example, it is determined that the rotation processing is performed on the odd-numbered units, but the invention is not limited to this, and it may be determined that the rotation processing is performed on the even-numbered units.
In this case as well, similarly, by performing the rotation processing on each image in the unit and then changing the image forming order, the unevenness of light and shade in the bonded portion becomes inconspicuous, and a good image can be obtained.

Here, an example is shown in which a plurality of sheets are laminated one-dimensionally in the sheet conveying direction, but the present invention is not limited to this. For example, as shown in FIG. 5, the same applies to the case of dividing an image so that sheets are two-dimensionally stuck together. For each of a plurality of partial images for which image formation is performed simultaneously,
It suffices to determine whether or not the rotation processing is necessary. In the case where image formation is performed for each column as in the example shown in FIG. 5, there is a case where a partial image in the column alone does not reach the unit for performing image formation at the same time, such as a partial image of “U”. But
In such a case, it is advisable to carry out image formation while the number of units is not reached. When the image formation is performed simultaneously with the partial image in the next row, a color difference due to uneven density may occur in the bonding portion between the rows.

In the first to fourth operation examples described above, the division processing is performed for each partial image while the drawing data remains unchanged. However, if the memory capacity is loosely limited, the drawing processing is performed first. Alternatively, the image data after the drawing process may be subjected to division processing.

In the above description, it has been explained that light and shade unevenness occurs in the carrying direction, but the present invention is not limited to this, and light and shade unevenness may occur in the direction orthogonal to the carrying direction.
In such a case, the rotation process is not necessary for the paper stuck in the carrying direction, but the rotation process is necessary for the sticking in the direction orthogonal to the carrying direction. For example, in the example as shown in FIG. 5, the rotation process may be performed by determining that the rotation process is performed on the odd-numbered column or the even-numbered column in FIG. 5C.

Although the first embodiment has been described above, the direction in which the unevenness in light and shade occurs, whether or not images of a plurality of pages can be simultaneously formed, etc. depend on the configuration and characteristics of the image forming apparatus 1. Therefore, as in the first embodiment, it is determined whether or not the rotation processing is performed in the image forming apparatus 1, and the rotation processing is performed as necessary, so that the processing on the host apparatus 2 side can be performed. A part depending on the image forming apparatus 1 can be eliminated, and the specifications can be standardized and simplified.

FIG. 10 is a block diagram showing an example of an image forming system showing a second embodiment of the present invention. In the figure,
The same parts as those in FIG. 1 are designated by the same reference numerals and the duplicated description will be omitted. Reference numeral 71 is an application, 72 is an output control unit, and 73 is a communication interface. In the second embodiment, an example is shown in which various processes related to divided printing are performed on the host device 2 side.

The output controller 72 uses the application 71.
Image data sent from the image forming apparatus 1 directly or via the operating system is converted into image data suitable for forming an image in the image forming apparatus 1 and transmitted to the image forming apparatus 1 via the communication interface 73. The output control unit 72 performs processing for the division printing if the division printing is designated at the time of conversion of the image data. The process at the time of this divided printing is almost the same as the process before the drawing which is performed by the printer controller 21 in the above-described first embodiment. Specifically, it is possible to perform the processing before drawing in each operation example shown in FIGS. 3 and 6 to 8. At this time, the output control unit 72 can perform these processes in the PDL data state. Alternatively, the drawing data in the image forming apparatus 1 is also expanded,
Similar processing can be performed. Further, it is also possible to output the image data to the image forming apparatus 1 after expanding it in the output control unit 72. At what stage the processing for divided printing is performed may be decided at the time of design.

In the second embodiment, since the processing relating to the division printing is performed on the host apparatus 2 side, the image forming apparatus 1 forms the image sent from the host apparatus 2 on the paper as usual. Just enough. Therefore, even in the image forming apparatus that does not have the division printing function, there is an advantage that the division printing function can be supported on the host device 2 side.

FIG. 11 is a block diagram showing an example of the image forming system showing the third embodiment of the present invention. In the figure,
The same parts as those in FIG. 1 are designated by the same reference numerals and the duplicated description will be omitted. Reference numeral 81 is a paper supply unit. In the paper supply unit 81, at least papers of the same size are set in different directions. That is, it is assumed that sheets having a short side parallel to the transport direction (sheets having a long side) and sheets having a long side parallel to the transport direction (sheets having a long side) are set. In the above-described first embodiment, a horizontally long sheet is used as a specific example. In the third embodiment, a vertically long sheet is used in the same case, and the partial image itself is also rotated by 90 degrees.

After the division processing, the drawing processing section 24 selects the paper for each of the divided partial images in consideration of the position where the paper is pasted after the image formation. For example, when unevenness in light and shade occurs in the transport direction, a vertically long sheet is selected when the sheets are pasted on the long side. Also, when pasting on the short side of the paper, the paper in the landscape direction is selected. Then, the partial image is rotated according to the selected paper. Further, in the case of two-dimensionally adhering paper sheets, the position of adhering each paper sheet is taken into consideration, and determination is made as to whether or not the rotation processing is to be performed along with the selection of such paper sheets. For a partial image determined to be rotated, for example, a case where rotation of 180 degrees is sufficient depending on the orientation of the selected paper and a case where rotation of 90 degrees is required and rotation processing of 270 degrees (or 90 degrees in the opposite direction) is required. May be done.

Paper of the size and direction selected by the printer controller 21 is fed to the print engine 27 from the paper supply unit 81. Then, the image (partial image) sent from the printer controller 21 is formed on the fed paper.

FIG. 12 is a flow chart showing an example of the operation at the time of division printing in the third embodiment of the present invention. In FIG. 12, the processing of S91 to S93 is the same processing as S31 to S33 in FIG. 3, and the processing of S97 is the same processing as S36 in FIG. 3, so redundant description will be omitted. Here, the operation when the sheets are bonded one-dimensionally is shown. In addition, it is assumed that uneven density occurs in the paper transport direction.

After the division processing is performed in S93, S9 is executed.
In 4, the bonding direction is determined. When the sheets are pasted together on the short sides of the sheets, the horizontally long sheets are selected in S95 so that the short sides of the sheets are parallel to the transport direction. If the sheets are pasted on the long sides of the sheets, the vertically long sheets are selected in S96 so that the long sides of the sheets are parallel to the transport direction. After that, in any case, after the image data drawing process is performed in S97, the drawn image data is passed from the engine control unit 26 to the print engine 27. At this time, the information of the paper sheet selected in S95 or S96. The paper supply unit 81 is controlled based on the above, and the paper in the selected direction is fed. Then, in the print engine 27, an image (partial image) is formed on the fed paper.

FIG. 13 is an explanatory diagram of a specific example of the division print result in the third embodiment of the invention. Here, the case where an image as shown in FIG. 13A, that is, a long image having the long side of the paper as the width is formed is shown. In this case, the long sides of the respective sheets are stuck together. In addition, it is assumed that light and shade unevenness occurs in the transport direction.

In such a case, as shown in FIG. 13B, the vertically long sheet is selected to form each partial image.
Figure 1 is obtained by pasting the paper on which the image is formed.
It is possible to obtain a long bonded image as shown in FIG. In this case, since it is expected that the same density change will occur in each sheet in the pasted portion, the pasted portion becomes less noticeable. Therefore, a good bonded image can be obtained.

FIG. 13D shows the case of forming a long image having the short side of the sheet as the width. In such a case, as shown in FIG. 13 (E), a horizontally long sheet may be selected to form an image for each partial image, and the sheets may be attached at their short sides. In this way, FIG.
It is possible to obtain a bonded image as shown in (F). In this case as well, since the density change at the pasted portion is the same for each sheet, the color difference at the pasted portion is small, and a good pasted image can be obtained.

Although the case where the papers are bonded one-dimensionally has been described here, a case where the papers are bonded two-dimensionally as shown in FIG. 5 described above can be considered. Such a case can be realized by combining rotation processing.

The above-described operation example corresponds to the first operation example in the first embodiment, but also in the third embodiment, the second to second operations in the first embodiment are performed.
The fourth operation example and other modifications can be similarly implemented. Further, as in the above-described second embodiment, it is possible to configure the host device 2 side to also select the paper.

[0070]

As is apparent from the above description, according to the present invention, even when images are formed on a plurality of sheets by using the division printing function and the images are pasted together, the color difference between the pasted portions can be reduced. Therefore, there is an effect that an image forming result with good image quality can be obtained.

[Brief description of drawings]

FIG. 1 is a system configuration diagram of an example of an image forming apparatus according to a first embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of an example of an image forming apparatus according to the first embodiment of the present invention.

FIG. 3 is a flowchart showing a first example of an operation at the time of division printing in the first embodiment of the present invention.

FIG. 4 is an explanatory diagram of a first specific example of a divided print result according to the first embodiment of the present invention.

FIG. 5 is an explanatory diagram of a second specific example of a division printing result according to the first embodiment of this invention.

FIG. 6 is a flowchart showing a second example of an operation during divided printing according to the first embodiment of the present invention.

FIG. 7 is a flowchart showing a third example of an operation at the time of division printing in the first embodiment of the present invention.

FIG. 8 is a flowchart showing a fourth example of an operation at the time of division printing in the first embodiment of the present invention.

FIG. 9 is an explanatory diagram of a third specific example of a division printing result according to the first embodiment of this invention.

FIG. 10 is a configuration diagram showing an example of an image forming system showing a second embodiment of the present invention.

FIG. 11 is a configuration diagram showing an example of an image forming system showing a third embodiment of the present invention.

FIG. 12 is a flowchart showing an example of an operation during divided printing according to the third embodiment of the present invention.

FIG. 13 is an explanatory diagram of a specific example of a divided print result according to the third embodiment of the present invention.

FIG. 14 is an explanatory diagram of an example of divided printing.

FIG. 15 is an explanatory diagram of an example of an image formed when division printing is performed in a conventional image forming apparatus.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Image forming apparatus, 2 ... Host apparatus, 11 ... Toner unit, 12 ... Drum unit, 13 ... Intermediate transfer body, 14
... fixing unit, 15 ... paper, 21 ... printer controller, 22 ... communication interface, 23 ... PDL analysis section, 24 ... drawing processing section, 25 ... storage section, 26 ... engine control section, 27 ... print engine, 71 ... application, 72 ... Output control unit, 73 ... Communication interface,
81 ... Paper supply unit.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H04N 1/387 H04N 1/387 1/393 1/393 F term (reference) 2C187 AC07 AF03 BF08 DB10 DB33 5B021 AA01 KK02 LB03 LE04 5B057 CD04 CD05 5C076 AA21 AA24 AA36 BA06

Claims (30)

[Claims] 1. An image forming apparatus having a function of forming one image on a plurality of sheets by dividing the image into a plurality of sheets, and controlling means for drawing and outputting an image to be formed on each sheet from input image data, The image forming means forms an image output from the controlling means on a sheet, and the controlling means is
When dividing one image into a plurality of sheets for each partial image and forming it, it is determined whether or not to perform the rotation process in consideration of the bonding position of each sheet for the partial image to be formed on each sheet. An image forming apparatus, wherein a partial image determined to be rotated is rotated by 180 degrees compared to other partial images. 2. The control unit determines that one of two partial images formed on a sheet to be laminated in a direction in which uneven shading occurs is subjected to a rotation process. Image forming device. 3. The control means determines whether or not the rotation processing is performed on the partial images, and further determines whether or not to change the image forming order, and rotates the partial images and changes the image forming order according to the determination result. The image forming apparatus according to claim 1, which is performed. 4. The control means determines a division mode from the size of the image and the size of the paper, and determines whether to perform the rotation processing according to the position of the paper after the bonding. The image forming apparatus according to claim 1 or 3, characterized in that the image forming apparatus comprises: 5. An image forming apparatus having a function of forming one image by dividing it into a plurality of paper sheets, and a paper supply means capable of loading at least vertically and horizontally long paper sheets,
Control means for selecting the paper loaded in the paper supply means from the input image data and drawing and outputting an image to be formed on each paper, and an image output from the control means by the control means Image forming means for forming on each sheet, the control means divides one image into a plurality of sheets for each partial image, and forms each image for each partial image on each sheet. An image forming apparatus characterized in that a sheet is selected in consideration of a bonding position of the sheets. 6. The image forming apparatus according to claim 5, wherein the control unit selects the sheet based on a direction of occurrence of unevenness of light and shade. 7. The control means determines a division mode from the size of the image and the size of the paper, and determines whether to perform the rotation process for each partial image according to the position of the paper after the bonding. The image forming apparatus according to claim 5 or 6, wherein the partial image determined to be rotated is subjected to a rotation process of 180 degrees compared to other partial images. 8. The control unit determines that the rotation process is not performed when it is determined that an image does not exist in a portion where the sheets are stuck together. The image forming apparatus according to item 1. 9. The image forming apparatus according to claim 1, wherein the control unit divides an image larger than a sheet into a plurality of sheets to form the image. 10. The control unit according to claim 1, wherein the control unit divides an image enlarged to a size larger than a sheet into a plurality of sheets to form the image.
The image forming apparatus according to item. 11. An image forming system in which a host device and an image forming device for forming an image on a sheet according to image data sent from the host device are connected, the host device communicating with the image forming device. And output control means for transferring image data to the image forming apparatus via the communication means. The output control means divides one image into a plurality of sheets for each partial image. And has a function of causing the image forming apparatus to form
When using this function, it is determined whether or not the rotation processing is performed for the partial images to be formed on each sheet in consideration of the bonding position of each sheet, and other partial images are determined for the partial image determined to be rotated. An image forming system characterized by performing a rotation process of 180 degrees as compared with. 12. The output control means determines that one of two partial images to be formed on sheets to be pasted in a direction in which light and shade unevenness occurs in the image forming apparatus is rotated. The image forming system according to claim 11. 13. The output control means determines whether or not to perform a rotation process on the partial images and further to change the image formation order, and rotates the partial images and changes the image formation order according to the determination result. The image forming system according to claim 11, wherein 14. The output control means determines a division mode from the size of the image and the size of the paper, and determines whether to perform the rotation process according to the position of the paper after the bonding. The image forming system according to claim 11 or 13, characterized in that. 15. In an image forming system connected to a host device and an image forming device for forming an image on a sheet according to image data sent from the host device, the image forming device has at least a portrait orientation and a landscape orientation. An image can be formed by selectively using a sheet, and the host device specifies a sheet to be used via the communication unit and a communication unit that communicates with the image forming apparatus, together with the image data to form the image data. The image forming apparatus has an output control unit that transfers the image to the apparatus, and the output control unit has a function of dividing one image into a plurality of sheets for each partial image and forming the image in the image forming apparatus. An image forming system characterized in that, when used, a partial image to be formed on each sheet is designated in consideration of a position where the sheets are attached to each other. 16. The image forming system according to claim 15, wherein the output control unit designates the sheet based on a direction of occurrence of uneven density in the image forming apparatus. 17. The output control means determines a division mode from the size of the image and the size of the paper, and determines whether to perform the rotation process for each partial image according to the position of the paper after the bonding. The image forming system according to claim 15 or 16, wherein the partial image determined to be subjected to the rotation process is subjected to a rotation process of 180 degrees compared to other partial images. 18. The output control means, when it is determined that an image does not exist in a portion where the sheets are stuck together,
18. The image forming system according to claim 11, wherein it is determined that the rotation processing is not performed. 19. The image forming apparatus according to claim 11, wherein the output control unit divides an image larger than a sheet into a plurality of sheets and forms the image on the image forming apparatus.
The image forming system according to any one of 1. 20. The output control means divides an image enlarged to a size larger than a sheet into a plurality of sheets and causes the image forming apparatus to form the image.
The image forming system according to claim 18. 21. In an image forming method for forming one image by dividing it into a plurality of sheets, whether or not to perform a rotation process on partial images formed on each sheet in consideration of the position of pasting each sheet. The image forming method is characterized in that the partial image determined to be subjected to the rotation process is subjected to a rotation process of 180 degrees as compared with other partial images, and each partial image is formed on a sheet. 22. The determination as to whether or not to perform the rotation processing is performed by determining that one of the two partial images to be formed on the sheets to be laminated in the direction in which the shading unevenness occurs is subjected to the rotation processing. The image forming method according to claim 21. 23. With respect to the partial image, it is determined whether or not the rotation processing is performed, and whether or not the image forming order is further changed, and the partial image is rotated and the image forming order is changed according to the determination result. Claim 2
1. The image forming method described in 1. 24. The division mode is determined from the size of the image and the size of the paper, and it is determined whether or not the rotation process is performed according to the position of the paper after the bonding. 24. The image forming method according to claim 21 or 23. 25. In an image forming method for forming one image by dividing it into a plurality of paper sheets, the partial image to be formed on each paper sheet has either a portrait orientation or a landscape orientation in consideration of a position of adhering each paper sheet. An image forming method, which comprises selecting a sheet and forming each partial image on the selected sheet. 26. The image forming method according to claim 25, wherein when the paper is selected, it is performed based on a generation direction of uneven density. 27. Further, the division mode is determined from the size of the image and the size of the paper, and it is determined whether or not the rotation process is performed for each partial image according to the position of the paper after the bonding, and the rotation is performed. 27. The image forming method according to claim 25 or 26, wherein the partial image determined to be processed is rotated by 180 degrees as compared with other partial images. 28. When determining whether to perform rotation processing,
The image forming method according to any one of claims 21 to 27, wherein when the image does not exist in the portion where the sheets are stuck together, it is determined that the rotation process is not performed. 29. The image forming method according to claim 21, wherein the image is an image larger than a sheet to be used. 30. The image forming method according to claim 21, wherein the image is an image enlarged to a size larger than a sheet to be used.