Image reading device and image forming apparatus

Abstract

To provide an image reading device that can efficiently read a document that exceeds a readable area without adding a separate member.SOLUTION: An image reading device 100 comprises a reading unit 20 and a control unit 30. The control unit 30 executes first processing, second processing, and third processing. In the first processing, the control unit 30 controls the reading unit 20 so that the reading unit 20 reads an image formed on a document M in a first direction D1 to obtain a first read image G1. In the second processing, the control unit 30 controls the reading unit 20 so that the reading unit 20 reads the image formed on the document M in a second direction D2 to obtain a second read image G2a. The second direction D2 is a direction opposite to the first direction D1.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an image reading device and an image forming device. [Background technology]

[0002] The A4 scanner described in Patent Document 1 includes a transport roller member. The A4 scanner described in Patent Document 1 can scan A3 paper by transporting the document using the transport roller member. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-273314 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the A4 scanner described in Patent Document 1 reads documents that exceed the readable area by adding a separate member such as a transport roller member in order to scan A3 paper.

[0005] The present invention has been made in consideration of the above-mentioned problems, and its purpose is to provide an image reading device and an image forming device that can efficiently read documents that exceed the readable area without adding any additional components. [Means for solving the problem]

[0006] An image reading device according to the present invention includes a reading unit and a control unit. The reading unit reads an image formed on a document and acquires a read image. The control unit controls the reading unit. The control unit executes a first process, a second process, and a third process. In the first process, the control unit controls the reading unit to read a portion of the document and acquire a first read image. In the second process, the control unit controls the reading unit to read at least a remaining portion of the document and acquire a second read image. In the third process, a document image is generated based on the first read image and the second read image. The document image represents the entire image formed on the document. In the first process, the control unit controls the reading unit to read the image formed on the document in a first direction and acquire the first read image. In the second process, the control unit controls the reading unit to read the image formed on the document in a second direction and acquire the second read image. The second direction is opposite to the first direction.

[0007] An image forming apparatus according to the present invention includes the image reading apparatus described above and an image forming section, which forms an image based on the document image. [Effects of the Invention]

[0008] According to the present invention, it is possible to efficiently read an original that exceeds the readable area without adding any additional components. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a schematic diagram illustrating an image reading device according to an embodiment of the present invention. [Figure 2] 1 is a schematic perspective view showing an image reading device according to an embodiment of the present invention; [Figure 3] 10(a) and 10(b) are diagrams showing the relationship between a document and a readable area. [Figure 4] 10(a) and 10(b) are diagrams showing the relationship between a document and a readable area. [Figure 5] 1(a) and 1(b) are diagrams showing a display unit. [Figure 6] FIG. [Figure 7] 10(a) and 10(b) are diagrams showing a state in which an original is placed on an original table. [Figure 8] 10A is a diagram showing a first read image, FIG. 10B is a diagram showing a second read image, and FIG. 10C is a diagram showing a reversed second read image. [Figure 9] FIG. 2 is a diagram showing an original image. [Figure 10] 10(a) to 10(c) are diagrams showing images of the overlapping portion. [Figure 11] 3 is a flowchart illustrating an image reading method of the image reading apparatus according to the embodiment of the present invention. [Figure 12] 10 is a flowchart showing a third process of the image reading device according to the embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts are designated by the same reference characters and description thereof will not be repeated.

[0011] An embodiment of an image forming apparatus 300 including an image reading device 100 according to the present invention will be described with reference to Figures 1 and 2. Figure 1 is a schematic diagram showing the image reading device 100 according to the embodiment of the present invention. Figure 2 is a schematic perspective view showing the image reading device 100 according to the embodiment of the present invention.

[0012] 1, the image forming apparatus 300 includes an image reading device 100, an image forming unit 50, a paper feed cassette 130, a conveying unit 140, and a discharge unit 170. The image forming apparatus 300 is, for example, an electrophotographic monochrome multifunction peripheral.

[0013] The image reading device 100 includes a reading unit 20, a control unit 30, a storage unit 40, a document table 12, and an operation unit 120. The image reading device 100 is an A4 size scanner.

[0014] The reading unit 20 reads an image formed on a document and acquires a read image. Specifically, the reading unit 20 reads an image formed on a document placed on the document table 12 and acquires a read image.

[0015] The reading unit 20 includes a light source 21, an optical system 26, and an imaging unit 27. The reading unit 20 is provided below the platen 12. The optical system 26 has a plurality of reflecting mirrors (reflecting mirror 24a, reflecting mirror 24b, and reflecting mirror 24c) and a lens 25. The light source 21 and the reflecting mirror 24a are attached to a first carriage 23a. The first carriage 23a is provided with a slit 22. The reflecting mirrors 24b and 24c are attached to a second carriage 23b.

[0016] Light emitted from light source 21 passes through optical system 26 and reaches imaging unit 27. The process by which light emitted from light source 21 reaches imaging unit 27 will be described below. Light source 21, which extends in main scanning direction DS2, illuminates platen 12 from below. Light emitted from light source 21 is reflected by the original, passes through slit 22, and reaches reflective mirror 24a. The light that reaches reflective mirror 24a is reflected by reflective mirror 24a, is guided by reflective mirrors 24b and 24c, passes through lens 25, and reaches imaging unit 27.

[0017] When the reading unit 20 reads an original, the first carriage 23a moves in the sub-scanning direction DS1 together with the emitting light source 21. More specifically, when the reading unit 20 reads an original, the first carriage 23a moves in the first direction D1 together with the emitting light source 21. The second carriage 23b moves so that the optical path length from the light source 21 to the imaging unit 27 remains constant. The reading unit 20 has a readable area AR in which an image formed on an original can be read.

[0018] The imaging unit 27 is, for example, a CCD (Charge Coupled Device). The imaging unit 27 generates an analog electrical signal from light that reaches the imaging unit 27. Then, an A / D conversion unit (not shown) converts the analog electrical signal into a digital electrical signal. The digital electrical signal is then input to the control unit 30.

[0019] The control unit 30 is a hardware circuit configured by a processor such as a CPU (Central Processing Unit), an ASIC (Application Specific Integrated Circuit), etc. The control unit 30 controls the operation of each unit of the image forming apparatus 300 by the processor reading and executing a control program stored in the storage unit 40. The control unit 30 controls, for example, the reading unit 20 and the storage unit 40.

[0020] The storage unit 40 is configured with a hard disk drive (HDD), a random access memory (RAM), and a read-only memory (ROM). The storage unit 40 may also include an external memory. The external memory is a removable medium. Examples of the external memory that the storage unit 40 includes include a universal serial bus (USB) memory and a secure digital (SD) card. The storage unit 40 stores various data and control programs for controlling the operation of each unit of the image forming apparatus 300. The control programs are executed by the control unit 30.

[0021] The image forming section 50 forms an image on a recording medium P based on an original image.

[0022] The operation unit 120 is used to allow a user to operate the image forming apparatus 300. More specifically, the operation unit 120 accepts an operation to set the size of a document. The operation unit 120 has a display unit 122 and operation buttons 124. The display unit 122 is, for example, a touch panel. An input screen for allowing a user to operate the image forming apparatus 300 is displayed on the display unit 122. The operation buttons 124 are, for example, hardware buttons.

[0023] The paper feed cassette 130 contains a recording medium P for printing. When printing, the recording medium P in the paper feed cassette 130 is transported by the transport unit 140 so as to pass through the image forming unit 50 and be discharged from the discharge unit 170.

[0024] Image reading device 100 is an A4 size scanner. In Fig. 2, home position HP indicates the position where reading unit 20 starts reading an image. Home position HP corresponds to one end of platen 12 in the sub-scanning direction. In Fig. 2, end position EP indicates the position where reading unit 20 ends reading an image. End position EP corresponds to the other end of platen 12 in the sub-scanning direction.

[0025] In the image reading device 100, when an image formed on an A4-sized document is read, the reading unit 20 reads the image formed on the document in the first direction D1. More specifically, the first carriage 23a moves in the first direction D1 together with the emitting light source 21 from the home position HP to the end position EP, thereby reading the image formed on the document. Reading of the image formed on the document ends when the image formed on the document up to the end position EP is completed. When reading of the image formed on the document up to the end position EP is completed, the first carriage 23a returns from the end position EP to the home position HP. When the first carriage 23a returns from the end position EP to the home position HP, it does not read the image formed on the document. In this specification, the process of reading the entire image formed on the document without reading the image formed on the document only in the first direction D1 may be referred to as "normal processing."

[0026] On the other hand, in the image reading device 100, when the length of the document in the first direction D1 is longer than the length of the document table 12 in the first direction D1, the image reading device 100 reads a portion of the document by reading the image in the first direction D1, and then reads the remaining portion of the document by reading the image in the second direction D2. The second direction D2 is the direction opposite to the first direction D1.

[0027] Specifically, when the length of the document in the first direction D1 is longer than the length of the document table 12 in the first direction D1, the control unit 30 executes a first process, a second process, and a third process. In the first process, the control unit 30 controls the reading unit 20 to read a portion of the document and acquire a first read image. In the first process, the control unit 30 controls the reading unit 20 to read an image formed on the document in the first direction D1 and acquire the first read image. In the second process, the control unit 30 controls the reading unit 20 to read at least a portion of the remaining document and acquire a second read image. In the second process, the control unit 30 controls the reading unit 20 to read an image formed on the document in the second direction D2 and acquire the second read image. In the third process, the control unit 30 generates a document image based on the first read image and the second read image. More specifically, in the third process, the control unit 30 generates an original image by combining the first read image and the second read image. The original image indicates the entire image formed on the original.

[0028] In this way, when the length of the document in the first direction D1 is longer than the length of the document table 12 in the first direction D1, the control unit 30 executes a first process for reading the image formed on the document in the first direction D1, as well as a second process for reading the image formed on the document in the second direction D2. Therefore, when the first carriage 23a returns from the end position EP to the home position HP, the remaining part of the image on the document can be read in the second process. As a result, a document beyond the readable area can be efficiently read without adding any additional components. In this specification, the process in which the control unit 30 executes the first process, the second process, and the third process to read the entire image formed on the document is sometimes referred to as a "combining process."

[0029] The relationship between the original document M and the readable area AR will be described with reference to Figures 3(a) to 4(b). Figures 3(a) to 4(b) are diagrams showing the relationship between the original document M and the readable area AR. In Figures 3(a) to 4(b), the readable area AR and the document table 12 are indicated by dashed lines. In Figures 3(a) to 4(b), the readable area AR is indicated by dot hatching.

[0030] In FIGS. 3(a) to 4(b), length dAR1 indicates the length of the readable area AR along the sub-scanning direction DS1. In FIGS. 3(a) to 4(b), length dAR2 indicates the length of the readable area AR along the main scanning direction DS2. In FIGS. 3(a) to 4(b), length dAR1 indicates the length of the readable area AR along the sub-scanning direction DS1. In other words, length dAR1 indicates the length of the readable area AR along the first direction D1. Length dAR1 is an example of a "first read length." In FIGS. 3(a) to 4(b), length dAR2 indicates the length of the readable area AR along the main scanning direction DS2. In FIGS. 3(a) to 4(b), length dM1 indicates the length of the original M along the sub-scanning direction DS1. In other words, length dM1 indicates the length of the original M along the first direction D1. Length dM1 is an example of a "first original length." 3(a) to 4(b), a length dM2 indicates the length of the original M along the main scanning direction DS2.

[0031] In this embodiment, the readable area AR is equal to the size of the platen 12. The length dAR1 is, for example, 297 mm. The length dAR2 is 215.9 mm. Note that the readable area AR may be smaller than the size of the platen 12.

[0032] The example shown in FIG. 3(a) shows an example in which an A4-sized document M1 is placed on the document table 12 as the document M. In the example shown in FIG. 3(a), the length dM1 is 297 mm. The length dM2 is 210 mm. Therefore, as shown in FIG. 3(a), the length dM1 is equal to the length dAR1. That is, in this embodiment, the length dAR1 is equal to the length of the long side of an A4-sized document (length dM1). Furthermore, the length dM2 is shorter than the length dAR1. Therefore, the document M1 falls within the readable area AR. If the document M falls within the readable area AR, the control unit 30 performs normal processing.

[0033] The example shown in FIG. 3(b) shows an example in which a legal-size document M2 is placed as the document M on the document table 12. In the example shown in FIG. 3(b), the length dM1 is 355.6 mm. The length dM2 is 215.9 mm. Therefore, as shown in FIG. 3(b), the length dM1 is longer than the length dAR1. Furthermore, the length dM2 is equal to the length dAR1. Therefore, the document M2 does not fit within the readable area AR. If the document M does not fit within the readable area AR, the control unit 30 performs a combining process.

[0034] The example shown in FIG. 4(a) shows an example in which a folio-sized document M3 is placed on the document table 12 as the document M. In the example shown in FIG. 4(a), the length dM1 is 330 mm. The length dM2 is 215.9 mm. Therefore, as shown in FIG. 4(a), the length dM1 is longer than the length dAR1. Furthermore, the length dM2 is equal to the length dAR1. Therefore, the document M3 does not fit within the readable area AR. If the document M does not fit within the readable area AR, the control unit 30 performs a combining process.

[0035] The example shown in FIG. 4(b) shows an example in which a custom-sized document M4 is placed on the document table 12 as the document M. In the example shown in FIG. 4(b), the length dM1 is 508 mm. The length dM2 is 107 mm. Therefore, as shown in FIG. 4(b), the length dM1 is longer than the length dAR1. Furthermore, the length dM2 is shorter than the length dAR1. Therefore, the document M4 does not fit within the readable area AR. If the document M does not fit within the readable area AR, the control unit 30 performs a combining process.

[0036] The setting screen for the size of the document to be read will be described with reference to Figures 5(a) to 6. Figures 5(a) to 6 are diagrams showing the display unit 122.

[0037] FIG. 5(a) shows a setting screen 210. More specifically, the setting screen 210 shows a menu selection screen. The setting screen 210 includes two menu selection buttons 212 and an end button 214. More specifically, the setting screen 210 includes a menu selection button 212a and a menu selection button 212b. "Custom Original Size" is assigned to the menu selection button 212a. "Default Original Size (Platen)" is assigned to the menu selection button 212b.

[0038] When the user touches menu selection button 212, a setting screen is displayed for setting the item assigned to menu selection button 212. For example, when the user touches menu selection button 212a, a setting screen for setting a custom size is displayed, as shown in Fig. 5(b). When the user touches menu selection button 212b, a setting screen for setting a default document scanning size is displayed.

[0039] The user can exit the setting screen 210 by touching the exit button 214. In other words, the setting screen 210 can be closed.

[0040] 5(b) shows the setting screen 220. The setting screen 220 includes an X-direction length setting section 222, a Y-direction length setting section 224, a cancel button 226, and a confirm button 228.

[0041] The X-direction length setting section 222 includes a minus button 222a, a plus button 222b, and an X-direction length display section 222c. The X-direction length of the document M to be set is displayed in the X-direction length display section 222c. The user can decrease the value displayed in the X-direction length display section 222c by touching the minus button 222a. On the other hand, the user can increase the value displayed in the X-direction length display section 222c by touching the plus button 222b. In this embodiment, the X-direction length of the document M can be changed within a range of 50 mm to 704 mm.

[0042] The Y-direction length setting section 224 includes a minus button 224a, a plus button 224b, and a Y-direction length display section 224c. The Y-direction length of the document M to be set is displayed in the Y-direction length display section 224c. The user can decrease the value displayed in the Y-direction length display section 224c by touching the minus button 224a. On the other hand, the user can increase the value displayed in the Y-direction length display section 224c by touching the plus button 224b. In this embodiment, the Y-direction length of the document M can be changed within a range of 50 mm to 704 mm.

[0043] The cancel button 226 is a button for canceling the values ​​set in the X-direction length setting section 222 and the Y-direction length setting section 224. When the user touches the cancel button 226, the values ​​set in the X-direction length setting section 222 and the Y-direction length setting section 224 are not reflected in the set size of the document to be read, and the screen returns to the setting screen 210 shown in FIG.

[0044] The Confirm button 228 is a button for confirming the values ​​set in the X-direction length setting section 222 and the Y-direction length setting section 224. When the user touches the Confirm button 228, the values ​​set in the X-direction length setting section 222 and the Y-direction length setting section 224 are reflected in the set size of the document to be read, and the screen returns to the setting screen 210 shown in FIG.

[0045] FIG. 6 shows a setting screen 230. The setting screen 230 includes five document size selection buttons 232 and an end button 234. In more detail, the setting screen 230 includes document size selection button 232a, document size selection button 232b, document size selection button 232c, document size selection button 232d, and document size selection button 232e. "A4" is assigned to the document size selection button 232a. "Letter" is assigned to the document size selection button 232b. "Legal" is assigned to the document size selection button 232c. "Folio" is assigned to the document size selection button 232d. "Custom" is assigned to the document size selection button 232e.

[0046] When the user touches document size selection button 232, the document size is set to the item assigned to document size selection button 232. For example, when the user touches document size selection button 232a, "A4" is set as the document size. When the user touches document size selection button 232b, "Letter" is set as the document size. When the user touches document size selection button 232c, "Legal" is set as the document size. When the user touches document size selection button 232d, "Folio" is set as the document size. When the user touches document size selection button 232e, "Custom" is set as the document size.

[0047] With reference to Figs. 7(a) to 9, a method for reading original M when original M does not fit within the range of readable area AR will be described. In particular, a method for reading original M when the length of original M in the first direction D1 is longer than the length of readable area AR in the first direction D1 will be described. In other words, a combining process will be described. In the example shown in Figs. 7(a) to 9, the size of original M5 is "Legal".

[0048] Fig. 7(a) is a diagram showing a state in which an original M5 is placed on the platen 12. Fig. 7(b) is a diagram showing a state in which an original M5 is placed on the platen 12. Fig. 8(a) is a diagram showing a first read image G1. Fig. 8(b) is a diagram showing a second read image G2a. Fig. 8(c) is a diagram showing a reversed second read image G2b. Fig. 9 is a diagram showing an original image G3.

[0049] 7(a), the document M5 does not fit within the readable area AR. In other words, the length dM1 of the document M along the first direction D1 is longer than the length dAR1 of the readable area AR along the first direction D1. In this case, the control unit 30 performs a combining process.

[0050] First, the control unit 30 acquires the length dM1 (first original length) along the first direction D1 of the original M. For example, the control unit 30 acquires the length dM1 (first original length) based on the size of the original M set by the operation unit 120.

[0051] As shown in FIG. 7(a), the user places the original M5 so that the left side of the original M5 overlaps the left side of the platen 12. When the user presses the scan execution button on the operation unit 120, the control unit 30 executes a first process. More specifically, the control unit 30 controls the reading unit 20 to read the image formed on the original M5 in the first direction D1 and acquire a first read image G1 (see FIG. 8(a)). In the first process, the first carriage 23a (see FIG. 1) moves in the first direction D1 from the home position HP to the end position EP, thereby causing the reading unit 20 to read a portion of the original M5.

[0052] As shown in FIG. 8(a), the first read image G1 includes a plurality of first read band images G1B. Here, the first read image G1 includes 28 first read band images G1B. The first read band image G1B1 indicates the first first read band image G1B, and the first read band image G1B28 indicates the 28th first read band image G1B. A band is a unit made up of a plurality of lines. In other words, the first read band image G1B indicates an image made up of a plurality of lines.

[0053] After acquiring the first scanned image G1, the first carriage 23a (see FIG. 1) stops at the end position EP. Then, the user places the original M5 so that the right side of the original M5 overlaps the right side of the platen 12. At this time, the control unit 30 displays, for example, an operation screen on the display unit 122 of the operation unit 120, requesting that the original M5 be moved and rescanned.

[0054] When the user places the original M5 so that its right side overlaps the right side of the platen 12 and requests rescanning via the operation screen, the control unit 30 executes the second process. Specifically, the control unit 30 controls the reading unit 20 to read the image formed on the remaining portion of the original M5 in the second direction D2 and acquire a second read image G2a (see FIG. 8(b)). More specifically, in the second process, the first carriage 23a (see FIG. 1) reads the image of the original M5 over a second read length d2 in the second direction D2 from the end position EP. The second read length d2 indicates the length along the first direction D1 when the reading unit 20 reads the image formed on the original M5 in the second direction D2.

[0055] The control unit 30 determines the second reading length d2 based on the length dAR1 (first reading length) and the length dM1 (first original length). Here, the length dAR1 (first reading length) is 297 mm, and the length dM1 (first original length) is 355.6 mm. Therefore, the second reading length d2 needs to be 355.6 mm - 297 mm = 58.6 mm or more. In this embodiment, the control unit 30 determines the second reading length d2 in band units.

[0056] The control unit 30 controls the reading unit 20 so that the first read image G1 and the second read image G2a have an overlapping portion where they overlap on at least one line. In this embodiment, the control unit 30 controls the reading unit 20 so that the first read image G1 and the second read image G2a have an overlapping portion where they overlap on multiple lines. More specifically, the control unit 30 controls the reading unit 20 so that the fourth second read band image G2B4 of the second read image G2a overlaps with the 28th first read band image G1B28 of the first read image G1. The first read band image G1B28 and the second read band image G2B4 correspond to an example of an "overlapping portion."

[0057] Then, as shown in FIG. 8(c), the control unit 30 inverts the second scanned image G2a by 180 degrees to generate an inverted second scanned image G2b.

[0058] Then, as shown in FIG. 9, the control unit 30 combines the first scanned image G1 and the inverted second scanned image G2b to generate an original image G3.

[0059] The first read image G1 and the second read image G2 are formed by a plurality of pixels arranged along a sub-scanning direction DS1 (first scanning direction) corresponding to the first direction D1 of the original M and a main scanning direction DS2 (second scanning direction) perpendicular to the sub-scanning direction DS1 (first scanning direction).

[0060] The image reading device 100 of the present invention will be further described with reference to Figure 10. Figures 10(a) to 10(c) are diagrams showing images of overlapping portions.

[0061] The control unit 30 determines whether the overlapping portions match. The control unit 30 determines whether the overlapping portions match. If the control unit 30 determines that the overlapping portions match, it executes a third process.

[0062] 10(a), the first read band image G1B28 and the second read band image G2B4 match. In this case, the control unit 30 executes the third process.

[0063] 10(b), the second scanned band image G2B4 is tilted relative to the first scanned band image G1B28. In this case, the control unit 30 does not execute the third process. In this case, for example, a message requesting a rescan may be displayed on the display unit 122 of the operation unit 120.

[0064] 10(b), the second read band image G2B4 is shifted to the right relative to the first read band image G1B28. In this case, the control unit 30 shifts the second read band image G2B4 to the left, and if the second read band image G2B4 matches the first read band image G1B28 as a result of shifting the second read band image G2B4 to the left, the control unit 30 executes the third process.

[0065] An image reading method of the image reading device 100 according to the embodiment of the present invention will be described with reference to Fig. 11. Fig. 11 is a flowchart showing the image reading method of the image reading device 100 according to the embodiment of the present invention. The image of the original M is read by executing the processes of steps S102 to S112 shown in Fig. 11.

[0066] Step S102: The control unit 30 acquires the length of the first original document. The process proceeds to step S104.

[0067] Step S104: The control unit 30 determines whether the first original length is longer than the first read length. If the control unit 30 determines that the first original length is not longer than the first read length (Step S104: No), the process proceeds to Step S114. If the control unit 30 determines that the first original length is longer than the first read length (Step S104: Yes), the process proceeds to Step S106.

[0068] Step S106: The control unit 30 executes a first process. Specifically, the control unit 30 controls the reading unit 20 to read the image formed on the document M in the first direction D1 and obtain a first read image G1. The process proceeds to step S108.

[0069] Step S108: The control unit 30 determines a second reading length based on the first reading length and the first original length. The first reading length indicates the length of the readable area AR along the first direction D1. The first original length indicates the length of the original along the first direction D1. The second reading length indicates the length along the first direction D1 when the reading unit 20 reads the image formed on the original M in the second direction D2 in the second process. The process proceeds to step S110.

[0070] Step S110: The control unit 30 executes a second process. Specifically, the control unit 30 controls the reading unit 20 to read the image formed on the document M in the second direction D2 and acquire a second read image G2a. The process proceeds to step S112.

[0071] Step S112: The control unit 30 executes a third process. Specifically, the control unit 30 generates an original image G3 representing the entire image formed on the original M based on the first read image G1 and the second read image G2a. The process then ends.

[0072] The third process will be described in detail with reference to Fig. 12. Fig. 12 is a flowchart showing the third process of the image reading device 100 according to an embodiment of the present invention. By executing the processes of steps S202 to S218 shown in Fig. 12, a document image G3 is generated.

[0073] Step S202: The control unit 30 calculates the degree of coincidence of the overlapping portion, and the process proceeds to step S204.

[0074] Step S204: The control unit 30 determines whether the overlapping portions match. If the control unit 30 determines that the overlapping portions match (Step S204: Yes), the process proceeds to Step S218. If the control unit 30 determines that the overlapping portions do not match (Step S204: No), the process proceeds to Step S206.

[0075] Step S206: The control unit 30 shifts the overlapping portion to one side in the main scanning direction DS2 (second scanning direction). Specifically, the control unit 30 shifts the overlapping portion to one side in the main scanning direction DS2 (second scanning direction) by an amount equivalent to 3% of the length of the overlapping portion along the main scanning direction DS2 (second scanning direction). The process proceeds to step S208.

[0076] Step S208: The control unit 30 calculates the degree of coincidence of the overlapping portion, and the process proceeds to step S210.

[0077] Step S210: The control unit 30 determines whether the overlapping portions match. If the control unit 30 determines that the overlapping portions match (Step S210: Yes), the process proceeds to Step S218. If the control unit 30 determines that the overlapping portions do not match (Step S210: No), the process proceeds to Step S212.

[0078] Step S212: The control unit 30 shifts the overlapping portion to the other side in the main scanning direction DS2 (second scanning direction). Specifically, the control unit 30 shifts the overlapping portion to the other side in the main scanning direction DS2 (second scanning direction) by an amount equivalent to 3% of the length of the overlapping portion along the main scanning direction DS2 (second scanning direction). The process proceeds to step S214.

[0079] Step S214: The control unit 30 determines whether the overlapping portions match. If the control unit 30 determines that the overlapping portions match (Step S214: Yes), the process proceeds to Step S218. If the control unit 30 determines that the overlapping portions do not match (Step S214: No), the process proceeds to Step S216.

[0080] Step S216: The control unit 30 displays a message to the effect that a rescan will be performed on the display unit 122 of the operation unit 120. The process then ends.

[0081] Step S218: The control unit 30 generates a document image G3, and the process ends.

[0082] As described above with reference to FIGS. 1 to 12, the control unit 30 executes a first process, a second process, and a third process. In the first process, the control unit 30 controls the reading unit 20 to read an image formed on the original M in the first direction D1 and acquire a first read image G1. In the second process, the control unit 30 controls the reading unit 20 to read an image formed on the original M in the second direction D2 and acquire a second read image G2. The second direction D2 is the opposite direction to the first direction D1. Therefore, when the first carriage 23a returns from the end position EP to the home position HP, the second process can read a remaining portion of the image of the original. As a result, an original beyond the readable area AR can be efficiently read without adding any additional components.

[0083] The control unit 30 also determines the second reading length d2 based on the first reading length (length dAR1) and the first original length (length dM1). The first reading length (length dAR1) indicates the length of the readable area AR along the first direction D1. The first original length (length dM1) indicates the length of the original M along the first direction D1, and the second reading length d2 indicates the length along the first direction D1 when the reading unit 20 reads an image formed on the original in the second direction D2 in the second process. Therefore, the image reading time (scanning time) can be minimized.

[0084] Furthermore, the control unit 30 acquires the first document length (length dM1) based on the size of the document M set by the operation unit 120. Therefore, the second reading length d2 can be determined in accordance with the size of the document M. As a result, the image reading time (scanning time) can be minimized.

[0085] Furthermore, the control unit 30 controls the reading unit 20 so that the first read image G1 and the second read image G2a have an overlapping portion where at least one line overlaps each other. Therefore, by comparing the overlapping portion between the first read image G1 and the second read image G2a, the first read image G1 and the second read image G2a can be appropriately combined.

[0086] Furthermore, the control unit 30 controls the reading unit 20 so that the first read image G1 and the second read image G2 have overlapping portions where multiple lines overlap each other. Therefore, by comparing the overlapping portions of the first read image G1 and the second read image G2a, the first read image G1 and the second read image G2a can be more appropriately combined.

[0087] Furthermore, the control unit 30 determines whether the overlapping portions match. If the control unit 30 determines that the overlapping portions match, it executes the third process. Therefore, when the reading unit 20 reads the original M in the second direction D2 (second process), if the original M is placed misaligned, the original image is not generated. Therefore, it is possible to suppress errors in generating the original image.

[0088] The embodiments of the present invention have been described above with reference to the drawings (FIGS. 1 to 12). However, the present invention is not limited to the above-described embodiments and can be embodied in various forms without departing from the spirit of the present invention. The drawings mainly show each component in a schematic manner for ease of understanding, and the thickness, length, number, etc. of each component shown in the drawings may differ from the actual components due to the convenience of creating the drawings. Furthermore, the materials, shapes, dimensions, etc. of each component shown in the above-described embodiments are merely examples and are not particularly limited, and various modifications are possible within a range that does not substantially depart from the effects of the present invention. [Industrial Applicability]

[0089] The present invention can be used in the fields of image reading devices and image forming devices. [Explanation of symbols]

[0090] 20 Reading unit 30 Control Unit 50 Image forming unit 100 Image reader 120 Operation section AR readable area D1 1st direction D2 2nd direction G1 First scanned image G2a Second scanned image G3 original image M, M1, M2, M3, M4, M5 manuscript

Claims

1. a reading unit that reads an image formed on a document and acquires the read image; a control unit that controls the reading unit; Equipped with The control unit a first process of controlling the reading unit to read a portion of the document and obtain a first read image; a second process of controlling the reading unit to read at least a portion of the remaining document and obtain a second read image; a third process of generating an original image showing the entire image formed on the original based on the first read image and the second read image; Run In the first process, the control unit controls the reading unit to read an image formed on the document in a first direction and acquire the first read image; In the second process, the control unit controls the reading unit to read an image formed on the document in a second direction and acquire the second read image; The second direction is opposite to the first direction.

2. the reading unit has a readable area in which an image formed on the document can be read, The control unit Obtain the length of the first manuscript; determining a second reading length based on the first reading length and the first document length; the first read length indicates the length of the readable area along the first direction, the first document length indicates a length of the document along the first direction, The image reading device according to claim 1 , wherein the second reading length indicates a length along the first direction when the reading unit reads the image formed on the document in the second direction in the second process.

3. an operation unit for receiving an operation for setting the size of the document; The image reading device according to claim 2 , wherein the control unit acquires the first document length based on the size of the document set by the operation unit.

4. 3. The image reading device according to claim 1, wherein the control unit controls the reading unit so that the first read image and the second read image have an overlapping portion where at least one line overlaps each other.

5. The image reading device according to claim 4 , wherein the control unit controls the reading unit so that the first read image and the second read image have the overlapping portion where a plurality of lines overlap.

6. The control unit determining whether the overlapping portions match; The image reading device according to claim 5 , wherein the third process is executed when it is determined that the overlapping portions match.

7. the first read image and the second read image are formed by a plurality of pixels arranged along a first scanning direction corresponding to the first direction of the document and a second scanning direction perpendicular to the first scanning direction, When the control unit determines that the overlapping portions do not match, The image reading device according to claim 6 , wherein the overlapping portion of the first read image or the overlapping portion of the second read image is shifted to one side in the second scanning direction or the other side in the second scanning direction.

8. The image reading device according to claim 1 or 2; an image forming unit that forms an image based on the original image; An image forming apparatus comprising:

Images