JP2008236597A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus capable of normally executing automatic adjustment. <P>SOLUTION: The image forming apparatus 1 includes an original reading section 42, an automatic adjusting section 44b and a touch panel 5b. The original reading section 42 acquires adjusting image data for adjusting the reading characteristics of an image consisting of a plurality of pixels. The automatic adjusting section 44b automatically adjusts the reading characteristics of the image on the basis of the adjusting image data. The touch panel 5b displays results as to whether the automatic adjusting section has normally executed automatic adjustment, for each block unit including at least one pixel of the adjusting image data, and accepts selection of pixels for validating or invalidating each of a plurality of pixels of the adjusting image data. If some block pixels are selected as invalid, the automatic adjusting section 44b re-executes automatic adjustment while using the pixels of the other blocks except the pixels of the blocks selected as invalid. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an image forming apparatus.

  An image forming apparatus such as a copying machine, a multifunction peripheral, or a facsimile reads an image described in a document to acquire image data, and an image forming unit that forms an image on a sheet based on the read image data. Is provided.

In such an image forming apparatus, individual differences occur in image reading characteristics in the document reading unit, such as color balance and focus. For example, as shown in Patent Document 1, during maintenance by a serviceman after manufacturing or installation, So-called automatic adjustment for adjusting image reading characteristics is performed for each device. In the automatic adjustment, an adjustment document having images of each color such as RGB is first read, and then input γ adjustment, matrix adjustment, and the like are performed based on the image data of the adjustment document.
JP 2000-324352 A

  However, in the above-described automatic adjustment method, for example, when an operator mistakenly sets a document other than the adjustment document on the image forming apparatus and the image forming apparatus erroneously reads the other document, Even when the document is dirty or scratched, the image forming apparatus performs automatic adjustment based on the read document, and thus automatic adjustment may not be performed normally. In such a case, image color misalignment or the like occurs.

  SUMMARY An advantage of some aspects of the invention is that it provides an image forming apparatus that can perform automatic adjustment normally.

  An image forming apparatus according to a first aspect includes an image data acquisition unit, an automatic adjustment unit, a display unit, and a pixel selection receiving unit. The image data acquisition unit acquires adjustment image data for adjusting the reading characteristics of an image composed of a plurality of pixels. The automatic adjustment unit automatically adjusts the image reading characteristics based on the adjustment image data. The display unit displays the result of whether or not the automatic adjustment by the automatic adjustment unit is normally performed for each reading unit including at least one pixel of the adjustment image data. The pixel selection receiving unit can receive, for each reading unit, selection of a pixel for validating or invalidating each of the plurality of pixels of the adjustment image data. When there is a pixel selected as invalid among the plurality of pixels of the adjustment image data, the automatic adjustment unit performs the automatic adjustment again using the remaining pixels excluding the pixel selected as invalid.

  According to this image forming apparatus, the display unit displays a result indicating whether or not the automatic adjustment has been normally performed for each reading unit including at least one pixel. A selection can be made to invalidate pixels that have not been performed. Then, the image forming apparatus performs automatic adjustment using valid pixels excluding those selected as invalid. As a result, the image forming apparatus performs the subsequent image forming operation using the adjustment value when automatic adjustment is performed using a document for automatic adjustment with dirt or scratches. Color misregistration can be prevented. Further, according to this image forming apparatus, it is possible to prevent a case where an adjustment value by automatic adjustment is used when an automatic adjustment is mistakenly performed for another document different from the document for automatic adjustment. Even when a plurality of originals are required as in the case of automatic adjustment of the back side of the user, the operator can know whether or not the plurality of originals are set in the correct order.

  An image forming apparatus according to a second aspect is the image forming apparatus according to the first aspect, wherein the pixel selection receiving unit can further receive a pixel selection before the automatic adjustment unit performs automatic adjustment. Then, when there is a pixel selected as invalid before the automatic adjustment, the automatic adjustment unit performs automatic adjustment using the remaining pixels excluding the pixel selected as invalid.

  According to this image forming apparatus, if the operator knows that the adjustment document is dirty or scratched before automatic adjustment, the operator invalidates the dirty or scratched pixel before automatic adjustment is performed. Selection can be made. Thereby, the accuracy of automatic adjustment is further improved.

  According to the image forming apparatus of the present invention, since automatic adjustment is normally performed, it is possible to prevent image color misregistration and the like from occurring.

(1) Configuration of Image Forming Apparatus FIG. 1 is an external view of an image forming apparatus 1 according to the present embodiment. This image forming apparatus 1 is a model of a multi-function machine having functions as a copying machine, a printer, a facsimile machine, and a scanner, and has an automatic adjustment mode for automatically adjusting the reading characteristics of an image composed of a plurality of pixels. Have.

  The image forming apparatus 1 in FIG. 1 includes an ADF (Automatic Document Feeder) 3, a main body 4, an operation panel 5, a paper feed cassette 6, and a discharge tray 7.

  The ADF 3 is mounted on the main body 4 so as to be openable and closable with respect to the document placing table 2, and has a document placing tray 3a and a document pressing portion 3b as shown in FIG. A plurality of documents to be copied are placed on the document placement tray 3a, and the plurality of documents placed on the document placement tray 3a are placed on the contact glass 2a of the document placement table 2 one by one. Be transported. The document pressing portion 3 b is for pressing a document placed on the platen glass 2 b of the document placing table 2. Here, as shown in FIG. 2, the platen glass 2b is provided in a portion of the main body 4 facing the ADF 3.

  As shown in FIG. 3, the main body unit 4 includes a communication unit 41, a document reading unit 42 (corresponding to an image data acquisition unit), an image forming unit 43, and a control unit 44.

  The communication unit 41 is for communicating with another terminal such as a PC, and can transmit and receive image data and the like.

  The document reading unit 42 is for reading a document on the contact glass 2a and the platen glass 2b in the document placing table 2, and includes a CCD and an optical system as shown in FIG. Examples of the type of document read in the present embodiment include a document serving as a basis for copying and an adjustment document D used during automatic adjustment. FIG. 4 is a schematic diagram illustrating an example of an adjustment document D used when automatic adjustment is performed. The adjustment document D is, for example, an A-size document, and includes adjustment images G1 to G7 for each color as shown in FIG. The adjustment originals G1 to G7 are arranged so as to extend in a direction intersecting with the conveyance direction (arrow direction in FIG. 4) of the adjustment original D, respectively. Further, the adjustment images G1, G2, and G3 are respectively set to red (R), green (G), and blue (B) in the three primary colors (R, G, and B). The adjustment images G4, G5, and G6 are respectively set to cyan (C), magenta (M), and yellow (Y) in the complementary colors (C, M, and Y). The adjustment image G7 is color-set to a gray with a predetermined gradation. Such an adjustment document D is conveyed by the ADF 3 in the direction of the arrow in FIG. 4 and read by the document reading unit 42. Hereinafter, the image data acquired by the original reading unit 42 reading the adjustment original D is referred to as “adjustment image data”, and in particular, the image data corresponding to each of the adjustment images G1 to G7 is referred to as “RGB pixel data”.

  The image forming unit 43 is for forming an image based on image data acquired from the document reading unit 42 or the communication unit 41, and includes a photosensitive drum, a developing device, and the like.

  The control unit 44 includes a microcomputer including a CPU, a RAM, and the like, and is connected to the operation panel 5, the communication unit 41, the document reading unit 42, the image forming unit 43, and the like as shown in FIG. The control unit 44 performs image forming processing, operation control of each connected input / output unit, and the like. The controller 44 will be described in detail in “(2) Configuration of controller”.

  As shown in FIG. 1, the operation panel 5 is provided on the front side of the document placing table 2 in the main body 4, and as shown in FIGS. 1 and 3, the operation keys 5 a and the touch panel 5 b (display unit and pixel selection). Equivalent to the reception part). The operation keys 5a include a start key for instructing the start of printing, a setting key for various settings, a numeric keypad, and the like. The touch panel 5b is composed of a liquid crystal display. For example, when the automatic adjustment setting screen (FIG. 5) or automatic adjustment is not normally performed, the pixel in the adjustment image data is selected as valid or invalid. A possible selection screen (FIG. 6) is displayed. When the selection screen of FIG. 6 is displayed on the touch panel 5b, the operator can select invalid pixels for each reading unit so that pixels with dirt or scratches are not used during automatic setting. .

  Here, the reading unit is a unit arbitrarily set so that the operator can easily select a pixel when selecting the pixel, and includes at least one pixel. For example, in FIG. 6, the portions of the adjustment images G1 to G7 in the adjustment document D are represented by being divided into seven blocks. In each block, if all the adjustment images G1 to G7 are composed of 448 pixels, for example, each block includes 64 pixels. In such a case, the operator can select an invalid block from the seven blocks divided every 64 pixels. Hereinafter, in order to simplify the description, the pixel reading unit is described as “block”.

  The paper feed cassette 6 can store paper and is provided in three stages below the main body 4 as shown in FIG.

  The discharge tray 7 is provided on the side surface of the main body unit 4 so as to protrude sideways, and the sheets after the image forming operation is performed by the image forming unit 43 inside the main body unit 4 are stacked.

(2) Configuration of Control Unit The control unit 44 according to the present embodiment performs automatic adjustment when the automatic adjustment mode is selected from the operation panel 5, for example. In order to perform such an operation, the control unit 44 functions as a mode control unit 44a, an automatic adjustment unit 44b, and an operation panel control unit 44c, as shown in FIG.

  The mode control unit 44 a controls the mode in which the image forming apparatus 1 operates based on various settings made via the operation panel 5. For example, when the copy function is designated from the operation panel 5, the mode control unit 44 a outputs an operation instruction in the copy mode to each connected function unit and each function unit in the control unit 44. When the automatic adjustment mode is designated, the mode control unit 44 a outputs an operation instruction in the automatic adjustment mode to each connected function unit and each function unit in the control unit 44.

  The automatic adjustment unit 44b performs automatic adjustment. Specifically, when the automatic adjustment unit 44b obtains an operation instruction in the automatic adjustment mode from the mode control unit 44a, the automatic adjustment unit 44b determines whether or not the pixels of the adjustment document D can be used for automatic adjustment. Adjust the reading characteristics. Here, examples of a method for adjusting the image reading characteristics include input γ adjustment and matrix adjustment. When the screen of FIG. 6 is displayed on the touch panel 5b of the operation panel 5 and an invalid pixel block is selected from the plurality of pixels in the adjustment image data by the operator, The automatic adjustment unit 44b performs automatic adjustment using the remaining pixels excluding the pixels of the selected block.

  The operation panel control unit 44 c controls the operation panel 5. For example, when the automatic adjustment mode is selected via the operation panel 5, the operation panel control unit 44c generates screen information of the automatic adjustment setting screen in FIG. 5 and outputs the screen information to the touch panel 5b. In addition, because there are pixels that cannot be used for automatic adjustment, when an error occurs in automatic adjustment, the operation panel control unit 44c, as shown in FIG. The screen information that can be displayed separately from the block is generated and output to the touch panel 5b.

(3) Operation FIG. 7 is a flowchart for explaining an operation flow of the image forming apparatus 1 according to the present embodiment.

  Step S1: When the automatic adjustment mode is designated via the operation panel 5, the operation panel control unit 44c controls the screen of FIG. 5 to be displayed on the touch panel 5b. As a result, the automatic adjustment setting screen shown in FIG. 5 is displayed on the touch panel 5b. Here, it is assumed that after the adjustment document D is placed on the document placing table 2 and the input γ adjustment or matrix adjustment is selected from the screen of FIG. 5, the start of automatic adjustment is instructed.

  Step S2: The document reading unit 42 reads the adjustment document D placed on the document table 2 and acquires adjustment image data for adjusting the image reading characteristics.

  Steps S3-7: The automatic adjustment unit 44b of the control unit 44 calculates the average value of the gradations indicated by the RGB pixel data in the adjustment image data (S3). Thereby, the average value of the gradation regarding the adjustment images G1 to G7 of the respective colors is obtained. Next, the automatic adjustment unit 44b calculates a ratio of RGB pixel data indicating a gradation that is a predetermined value or more away from the average value obtained in step S3 for each of the adjustment images G1 to G7 for each color (S4). It is determined whether or not it is 20% or more (S5). If the ratio is not 20% or more in step S5 (NO in S5), the automatic adjustment unit 44b determines that the gradation of the red (R) RGB pixel data corresponding to the color of the adjustment image G1, for example, is three primary colors ( It is determined whether or not it is smaller than the gradation of each RGB pixel data of green (G) and blue (B), which are other colors of R, G, B) (S6). The automatic adjustment unit 44b performs the operations in steps S4 to S7 for all seven colors (S7). That is, in step S6, for the three primary colors (R, G, B), green (G) and blue (B), each gradation of red (R) and blue (B) is a green (G) gradation. If it is a gradation of blue (B), it is determined whether it is smaller than each gradation of red (R) and green (G).

  The adjustment images G4 to G6 indicate cyan (C), magenta (M), and yellow (Y) colors corresponding to the complementary colors of the three primary colors (R, G, B). ) Of the adjustment image G4, it is compared whether or not the red (R) gradation in the adjustment image G4 is larger than the gradations of green (G) and blue (B). In this case, when the gradation of red (R) in the adjustment image G4 is larger than the gradations of green (G) and blue (B), the automatic adjustment unit 44b determines that automatic adjustment is not normally performed. To do.

  Note that since the color of the adjustment image G7 is gray, the gradations of the RGB pixel data corresponding to each of the three primary colors (R, G, B) are equal to each other. Accordingly, the automatic adjustment unit 44b determines that the automatic adjustment is not normally performed when the gradation difference of the RGB pixel data corresponding to each of the three primary colors (R, G, B) is, for example, 30 gradations or more. To do.

  Step S8: After the operation of Steps S4 to S7 is completed for all the adjustment images G1 to G7 in Step S7, the automatic adjustment unit 44b is set in Step S1 for all the pixels in the adjustment image data. Perform input γ adjustment or matrix adjustment.

  Step S9: When the ratio obtained in Step S4 is 20% or more (YES in S5), for example, in the adjustment image G1, the gradation of red (R) is the gradation of green (G) and blue (B) Is smaller (NO in S6), the automatic adjustment unit 44b determines that the automatic adjustment has not been performed normally. Then, the operation panel control unit 44c divides the adjustment images G1 to G7 in the adjustment document D into a plurality of blocks according to the total number of pixels, and then blocks that have not been automatically adjusted and blocks that have been normally performed. Are displayed on the touch panel 5b in a distinguishable and selectable manner. Thereby, the screen shown in FIG. 6 is displayed on the touch panel 5b.

  Steps S10 to 11: When a block to be invalidated in automatic adjustment is selected via the touch panel 5b (YES in S10), the automatic adjustment unit 44b selects the selected block among all the pixels in the adjustment document D. Input γ adjustment or matrix adjustment is performed using pixels of the remaining blocks except for (S11). In step S10, if the operator does not select a block to be invalidated in automatic adjustment (NO in S10), the image forming apparatus 1 ends the series of operations without performing automatic adjustment again. .

(4) Effect According to the image forming apparatus 1, the touch panel 5b of the operation panel 5 displays a result indicating whether or not the automatic adjustment has been normally performed in units of blocks including at least one pixel. For example, the operator can select to invalidate pixels for which automatic adjustment has not been normally performed. Then, the image forming apparatus 1 performs automatic adjustment using pixels of a valid block excluding pixels of a block selected as invalid. As a result, the image forming apparatus 1 performs the subsequent image forming operation using the adjustment value when the automatic adjustment is performed using the adjustment document with dirt or scratches. It is possible to prevent the deviation from occurring. Further, according to the image forming apparatus 1, it is possible to prevent a case where an adjustment value by automatic adjustment when an automatic adjustment is mistakenly performed on another document different from the adjustment document, and the DP's Even when a plurality of adjustment originals are required as in the case of automatic adjustment of the back side, the operator can know whether or not the plurality of adjustment originals are set in the correct order.

<Other embodiments>
(A) In the above embodiment, as shown in FIG. 7, the case where the selection screen of FIG. 6 is displayed on the touch panel 5 b only after the automatic adjustment has been described. However, the selection screen of FIG. May be displayed. The main operation flow of the image forming apparatus 1 in this case is shown in FIG. The operation of the image forming apparatus will be briefly described below with reference to FIG. Note that the image forming apparatus according to this embodiment has the same configuration as that of the image forming apparatus 1 according to the above-described embodiment. .

  Step S101: When the automatic adjustment mode is designated via the operation panel 5, the automatic adjustment setting screen shown in FIG. 5 is displayed on the touch panel 5b. Here, it is assumed that after the adjustment document D is placed on the document placement table 2 and the input γ adjustment or matrix adjustment is designated by the operator from the screen of FIG. 5, the start of automatic adjustment is instructed.

  Step S102: The document reading section 42 reads the adjustment document D placed on the document table 2 and acquires adjustment image data for adjusting the image reading characteristics.

  Step S103: When the document reading unit 42 acquires the adjustment image data, the operation panel control unit 44c of the control unit 44 divides the adjustment images G1 to G7 in the adjustment document D into a plurality of blocks according to the total number of pixels, Each of these blocks is displayed on the touch panel 5b so that it can be selected. Thereby, the operator can select to invalidate a block including a part that is known in advance as being dirty or scratched, for example.

  Steps S104 to S105: When a block to be invalidated in automatic adjustment is selected (YES in S104), the automatic adjustment unit 44b selects the selected block among the adjustment images G1 to G7 in the adjustment document D. Automatic adjustment is performed for the pixels of the remaining blocks (S105). The detailed contents of the automatic adjustment in step S105 correspond to steps S3 to S8 in FIG.

  Step S106: If a block to be invalidated is not selected in Step S104 (NO in S104), the automatic adjustment unit 44b performs automatic adjustment for all pixels (S106). Note that the detailed contents of the automatic adjustment in step S106 correspond to steps S3 to S8 in FIG.

  Steps S107 to 108: For example, when the automatic adjustment unit 44b determines that the automatic adjustment has not been normally performed (YES in Step S107), such as YES in Step S5 in FIG. The unit 44c displays the adjustment images G1 to G7 on the adjustment document D on the touch panel 5b so that the blocks in which the automatic adjustment is not normally performed and the blocks in which the automatic adjustment is normally performed can be distinguished and selected (S108). Thereby, the screen shown in FIG. 6 is displayed on the touch panel 5b. If the automatic adjustment is normally performed in step S107, the image forming apparatus 1 ends the series of operations.

  Steps S109 to 110: When a block to be invalidated in the automatic adjustment is selected from the screen in step S108 (YES in S109), the automatic adjustment unit 44b reads the adjustment images G1 to G7 in the adjustment document D. Among them, input γ adjustment or matrix adjustment is performed using the pixels of the remaining blocks excluding the selected block (S110). If no invalid block is selected in step S109 (NO in S109), the image forming apparatus 1 ends the series of operations without performing automatic adjustment again.

  According to such an image forming apparatus 1, when the operator knows that the adjustment document D is dirty or scratched before automatic adjustment, the operator automatically adjusts the block including the dirty or scratched pixel. A selection can be made to disable before the is done. Thereby, the accuracy of automatic adjustment is further improved.

  (B) In the above embodiment, the case where the operator selects a block via the touch panel 5b of the operation panel 5 has been described. However, the block selecting operation may be performed via the operation key 5a.

  The image forming apparatus according to the present invention can be applied to an apparatus including a document reading unit that reads a document, such as a copying machine or a scanner.

1 is an external view of an image forming apparatus according to an embodiment. 1 is a longitudinal sectional view showing in detail an ADF, a document placing table, and a document reading unit of an image forming apparatus according to an embodiment. 1 is a block diagram schematically showing a configuration of an image forming apparatus according to an embodiment. FIG. 3 is a schematic diagram illustrating an example of an adjustment document used when automatic adjustment is performed. The example of a screen displayed on the touch panel which concerns on this embodiment. The example of a screen displayed on the touch panel which concerns on this embodiment. FIG. 3 is a flowchart showing an operation flow of the image forming apparatus according to the embodiment. FIG. 10 is a flowchart showing a flow of operations of an image forming apparatus according to another embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 5 Operation panel 5a Operation key 5b Touch panel 42 Original reading part 43 Image forming part 44 Control part 44a Mode control part 44b Automatic adjustment part 44c Operation panel control part

Claims (2)

An image data acquisition unit for acquiring image data for adjustment for adjusting the reading characteristics of an image composed of a plurality of pixels;
An automatic adjustment unit for automatically adjusting the reading characteristics of the image based on the adjustment image data;
A display unit that displays a result of whether or not automatic adjustment by the automatic adjustment unit has been normally performed for each reading unit including at least one pixel of the image data for adjustment;
A pixel selection receiving unit capable of receiving, for each reading unit, selection of the pixels for enabling or disabling each of the plurality of pixels of the adjustment image data;
With
The automatic adjustment unit performs the automatic adjustment using the remaining pixels other than the pixels selected as invalid when the pixels selected as invalid are among the plurality of pixels of the adjustment image data. Do again,
Image forming apparatus. The pixel selection receiving unit can further receive the selection of the pixel before the automatic adjustment unit performs the automatic adjustment,
The automatic adjustment unit performs the automatic adjustment using the remaining pixels excluding the pixels selected as invalid when there is the pixel selected as invalid before the automatic adjustment.
The image forming apparatus according to claim 1.

Images