JP2023066247A - Image reading device and image reading system - Google Patents

Abstract

To eliminate the influence of disturbance light that is incident on a document platen to efficiently cut out images of documents through crop processing.SOLUTION: When crop processing is executed with a document holding cover 39 of an image reading unit 15 opened, a control unit 21 of an image forming apparatus 10 causes a reading unit 32 of the image reading unit 15 to perform pre-scanning to detect disturbance light incident on a second platen glass 42 based on a read image read by the reading unit 32, determines whether an image of a document included in the read image can be specified and cut out based on the detected disturbance light, and when the image of the document cannot be specified and cut out, controls an illumination device 50 to reduce the quantity of light of the illumination device 50.SELECTED DRAWING: Figure 1

Description

The present invention relates to an image reading apparatus and an image reading system, and more particularly to a technique for controlling the amount of light of an illumination device when crop processing is performed to read an image of a document with the document holding cover of the image reading section opened.

As an example of an image reading device, in an image forming device such as a multifunction machine, when a plurality of small documents (cards, etc.) are placed on the platen, an image reading unit such as a scanner reads the range of the platen, and this reading is performed. Crop processing is performed to specify and cut out the image of each document from the scanned image in the range.

Also, when cropping, open the document holding cover, open the document table, place multiple documents on the document table, close the document holding cover, cover the document table with the document holding cover, and read the image of each document. If the image reading section repeats the operation of performing the above operations, the work efficiency will be low. can be read.

However, when the document holding cover is open, the light from the illumination device may become disturbance light and enter the document platen. I can't do it.

In Japanese Patent Application Laid-Open No. 2004-100000, the incident range of disturbance light on the document platen is determined based on the output of an image pickup device (CCD) that reads the image of each document placed on the document platen, and the incident light is detected from the area read by the image pickup device. By excluding the range, the original image is specified and cut out.

Further, in Patent Document 2, in the process of closing the document cover, the size of the document is determined based on the output of an image pickup device (CCD) that reads the image of the document placed on the document platen, and the image is reflected by the document cover. The opening/closing angle of the document cover at which the emitted light is incident as disturbance light is obtained in advance, and the size of the document is not determined based on the opening/closing angle while the document cover is being closed.

Further, in Japanese Patent Application Laid-Open No. 2002-100000, each document placed on a document platen is pre-scanned by an image reading device to determine the presence or absence of ambient light. A message prompting the user to move or turn off the lighting device is displayed on the display unit.

Further, in Japanese Patent Laid-Open No. 2004-100000, each document placed on a document platen is pre-scanned by an image reading device to determine the presence or absence of ambient light. A message prompting the user to move or to turn off the illumination device is displayed on the display unit, and the presence or absence of the disturbance light is continuously determined in real time with respect to the area of the platen where the disturbance light is incident.

Japanese Patent Application Laid-Open No. 2001-346009 JP 2009-111908 A JP 2019-29853 A JP 2019-29854 A

However, in Japanese Patent Application Laid-Open No. 2002-200011, the incident range of ambient light is excluded from the area read by the imaging device, and the image of the document is specified and cut out. read count increases.

In addition, in Patent Document 2, when the position of the image reading device or the position of the lighting device is changed, the opening and closing angle of the document cover at which the light reflected by the document cover enters as disturbance light also changes. It is necessary to redo acquisition of the opening/closing angle of the cover.

Further, in Patent Documents 3 and 4, the user must respond to a message prompting the user to move the image reading device or to turn off the lighting device, which prevents efficient processing.

SUMMARY OF THE INVENTION The present invention has been devised in view of the above circumstances, and is capable of suppressing the influence of disturbance light and efficiently cutting out an image of each document by cropping when the disturbance light is incident on the platen. The purpose is to

An image reading apparatus according to one aspect of the present invention includes a translucent platen on which a document is placed, and a platen that can be freely opened and closed with respect to the platen. and a document holding cover that covers the document placed on the document platen; and a control unit that controls the image reading unit and controls at least one illumination device provided around the image reading unit and separate from the image reading device. The control section has a crop processing function of causing the image reading section to perform reading, and specifying and cropping an image of the document on the document platen included in the read image read by the image reading section. When the cropping process is executed with the document holding cover open, pre-scanning is performed by the image reading section, and the document is incident on the document table based on the read image read by the image reading section. detecting ambient light that is generated, and based on the detected ambient light, it is determined whether or not it is possible to specify and cut out the image of the document contained in the read image, and the image of the document is determined. When it is not possible to specify and cut out, the lighting device is controlled to reduce or set the light amount of the lighting device to zero.

An image reading system according to one aspect of the present invention includes an image reading device and at least one illumination device provided around the image reading device, the image reading device having translucency, a document table on which a document is placed; a document holding cover which is provided to be openable and closable with respect to the document table and covers the document table and the document placed on the document table when closed; an image reading unit for irradiating a document placed on a document platen with light through the document platen to read an image of the document through the document platen; and a control unit for controlling, the control unit causes the image reading unit to perform reading, and specifies and cuts the image of the document on the document table included in the read image read by the image reading unit. When the cropping process is executed with the document holding cover open, pre-scanning is performed by the image reading unit, and the image read by the image reading unit is read. Disturbance light incident on the platen is detected based on the image, and whether or not it is possible to specify and cut out the image of the document contained in the read image based on the detected disturbance light. If it is not possible to specify and cut out the image of the document, the illumination device is controlled to reduce or set the light amount of the illumination device to zero.

According to the present invention, when ambient light is incident on the platen, the influence of the ambient light can be excluded, and the image of each document can be cut out efficiently by crop processing.

1 is a block diagram showing an image reading system, a configuration of an image forming apparatus, and a configuration of an illumination device in the image reading system according to the first embodiment of the present invention; FIG. 1 is a perspective view showing an appearance of an image forming apparatus; FIG. 1 is a perspective view showing an appearance of an image reading device provided in an image forming apparatus, showing a state in which a document conveying section of the image reading device is opened; FIG. 1 is a cross-sectional view showing an image reading device; FIG. FIG. 2 is a plan view showing an image reading unit and a second platen glass of the image reading device as viewed from above; 4 is a flow chart showing the flow of processing when crop processing is executed in the image forming system according to the first embodiment; FIG. 4 is a diagram showing an open/close selection screen displayed on the display unit of the image forming apparatus; FIG. 10 is a diagram showing a screen of the display unit of the image forming apparatus displaying a message notifying that pre-scanning will be performed; FIG. 10 is a diagram showing a screen of the display unit of the image forming apparatus displaying a message notifying that cropping can be performed while the document holding cover is open; FIG. 10 is a view showing a screen of the display unit of the image forming apparatus displaying a message notifying that the amount of light of the illumination device is to be reduced because the cropping process cannot be performed while the document holding cover is open; FIG. 10 is a diagram showing a screen of the display unit of the image forming apparatus displaying a message notifying that cropping processing cannot be executed while the document holding cover is open; FIG. 7 is a block diagram showing an image reading system according to a second embodiment of the present invention, and a configuration of an image forming apparatus and a configuration of an illumination device in the image reading system; 10 is a flow chart showing the flow of processing when crop processing is executed in the image forming system according to the second embodiment;

An image reading system according to an embodiment of the present invention will be described below with reference to the drawings.
<First embodiment>
FIG. 1 is a block diagram showing an image reading system according to a first embodiment of the present invention, and a configuration of an image forming apparatus and a configuration of an illumination device in the image reading system. The image reading system Sy of this embodiment includes an image forming apparatus 10, which is an embodiment of the image reading apparatus according to the present invention, and an illumination device 50. As shown in FIG.

In the image reading system Sy, the image forming apparatus 10 is, for example, an MFP (composite machine) having multiple functions such as a copy function, a printer function, and a scanner function. The image forming apparatus 10 includes a display unit 11, an operation unit 12, a touch panel 13, a short-range communication unit 14, an image reading unit 15, an image forming unit 16, an image memory 17, a storage unit 18, a control unit 19, and the like. there is These components are enabled to send and receive data or signals to and from each other through the bus.

The display unit 11 includes a liquid crystal display (LCD), an organic light emitting diode (OLED) display, or the like.

A touch panel 13 is superimposed on the screen of the display unit 11 . The touch panel 13 detects contact (touch) of a user's finger or the like on the touch panel 13 together with the contact position, and outputs a detection signal indicating the coordinates of the contact position to the control section 21 of the control unit 19, which will be described later.

The operation unit 12 includes hard keys such as a numeric keypad, an enter key, and a start key. Various operation instructions are input to the operation unit 12 by the operator according to the operation of each key.

The image reading unit 15 has an image sensor for optically reading an image of a document, and converts an analog output of the image sensor into a digital signal to generate image data representing the image of the document. In the image reading unit 15, an image of a document placed on a document platen (second platen glass 42 to be described later) is read by the image sensor, or one or more images set on the document tray are read. An ADF (automatic document feeder) is provided for pulling out and conveying originals one by one, and the image of the original being conveyed by the ADF is read by the imaging element.

The image forming unit 16 includes a photoreceptor drum, a charging device that uniformly charges the surface of the photoreceptor drum, an exposure device that exposes the surface of the photoreceptor drum to form an electrostatic latent image on the surface of the photoreceptor drum, and a photoreceptor. Equipped with a developing device that develops the electrostatic latent image on the surface of the drum into a toner image, and a transfer device that transfers the toner image (image) on the surface of the photosensitive drum to recording paper, etc., and records the image indicated by the above image data. print on paper.

The short-range communication unit 14 is, for example, a communication device having a communication function such as Bluetooth low energy or Bluetooth (Bluetooth Low Energy (BLE), Bluetooth: registered trademark). 50 for data communication.

The image memory 17 stores image data representing the image of the document read by the image reading section 15 .

The storage unit 18 is a large-capacity storage device such as an SSD (Solid State Drive) or HDD (Hard Disk Drive), and stores various application programs and various data.

The control unit 19 includes a processor, RAM (Random Access Memory), ROM (Read Only Memory), and the like. The processor is, for example, a CPU (Central Processing Unit), an ASIC (Application Specific Integrated Circuit), or an MPU (Micro Processing Unit). The control unit 19 functions as the control section 21 by executing the control program stored in the ROM or the storage section 18 by the processor.

The control unit 21 controls overall control of the image forming apparatus 10 . The control unit 19 is also connected to the display section 11, the operation section 12, the touch panel 13, the short-range communication section 14, the image reading section 15, the image forming section 16, the image memory 17, the storage section 18, and the like. The control unit 21 controls each component and transmits/receives signals or data to/from each component.

The control unit 21 serves as a processing unit that executes various processes required for image formation by the image forming apparatus 10 .

Further, the control unit 21 receives operation instructions input by the user based on detection signals output from the touch panel 13 or physical key operations of the operation unit 12 . For example, the control unit 21 receives a touch operation on a GUI (Graphical User Interface) displayed on the screen of the display unit 11 through the touch panel 13 .

Furthermore, the control unit 21 has a function of controlling the display operation of the display unit 11 and a function of controlling the communication operation of the near field communication unit 14 .

Next, in the image reading system Sy, the illumination device 50 includes a light source 51 , a power supply section 52 , a short-range communication section 54 and a control section 55 . These components are enabled to send and receive data or signals to and from each other through the bus.

The light source 51 is made up of, for example, an LED, and emits light upon being supplied with power from the power supply unit 52 to emit illumination light.

The short-range communication unit 54 is a communication device having a communication function such as Bluetooth Low Energy (BLE) or Bluetooth (registered trademark), and image formation is performed by short-range communication based on the communication function. It transmits and receives data to and from the device 10 .

The control unit 55 is, for example, a microcomputer, is connected to the power supply unit 52 and the short-range communication unit 54, and controls them.

Next, the image reading section 15 in the image forming apparatus 10 will be described. FIG. 2 is a perspective view showing the appearance of the image forming apparatus 10. As shown in FIG. 3 is a perspective view showing the appearance of the image reading section 15, showing a state in which the document conveying section 31 is opened. FIG. 4 is a sectional view showing the image reading section 15. As shown in FIG.

As shown in FIG. 2, the image forming apparatus 10 includes a main housing 20, an image reading unit 15 is mounted on the main housing 20, and a paper feeder that supplies recording paper to the front lower side of the main housing 20. A paper cassette 7 is provided. An image forming section 16 that forms a toner image on recording paper supplied from the paper feed cassette 7 is provided in the internal space above the paper feed cassette 7 in the main body housing 20 . The recording paper supplied from the paper feed cassette 7 and on which the image is formed by the image forming section 16 is discharged to the paper discharge tray 8 .

As shown in FIGS. 3 and 4, the image reading section 15 includes a document conveying section 31 and a reading section 32 . The document transport unit 31 includes a document tray 33, a paper feed roller 34, a registration roller 35, a plurality of transport rollers 36, a paper discharge roller 37, a document discharge tray 38, and the like. The reading unit 32 also includes a first platen glass 41, a second platen glass 42, a carriage 44, an optical system unit 45, a condenser lens 46, a CCD sensor 47, and the like. The second platen glass 42 is an example of a platen in the claims.

In the reading unit 32, the carriage 44 has a light source 44A for irradiating light onto the document and a mirror 44B for reflecting the light reflected by the document M. As shown in FIG.

The optical system unit 45 includes mirrors 45A and 45B. The mirror 45A receives the light reflected by the mirror 44B of the carriage 44 and changes the direction substantially vertically downward. The mirror 45B redirects the light reflected by the mirror 45A to a substantially horizontal direction and guides the light to the CCD sensor 47 through the condenser lens 46 .

The carriage 44 and optical system unit 45 are provided so as to be reciprocally movable along rails in the sub-scanning direction X perpendicular to the main scanning direction Y, and are driven by a known drive mechanism powered by a stepping motor (not shown). is moved in the sub-scanning direction X while maintaining the speed relationship of .

Two hinges 48 are spaced apart from one end of the top surface 32A of the reading unit 32. These hinges 48 support the document conveying unit 31 so that the document conveying unit 31 can be opened and closed by the user. operation is enabled. A document pressing cover 39 is provided on the lower surface of the document conveying section 31 . When the document conveying section 31 is closed, the document pressing cover 39 covers the first platen glass 41 and the second platen glass 42 . Therefore, the document holding cover 39 is provided so as to be openable and closable with respect to the second platen glass 42, and covers the second platen glass 42 when closed.

The image reading unit 15 also has a first mode for reading the image of the document M placed on the second platen glass 42 and a second mode for reading the image of the document M while the document M is conveyed by the document conveying unit 31 . Either of two modes can be switched. For example, a first sensor (not shown) that detects the document M placed on the second platen glass 42 and a second sensor (not shown) that detects the document M placed on the document tray 33 of the document transport section 31 . A sensor (not shown) is provided. When the document M is detected by the first sensor, the first mode is set, and when the document M is detected by the second sensor, the second mode is set.

For example, the user opens the document conveying section 31 and the document holding cover 39, places the document M on the second platen glass 42, closes the document conveying section 31, further operates the start key of the operation section 12, Assume that the control unit 21 has received a document reading instruction. When the document is detected by the first sensor, the control section 21 sets the first mode, and causes the reading section 32 to read the image of the document M on the second platen glass 42 according to the document reading instruction. In the reading unit 32, the carriage 44 and the optical system unit 45 are moved in the sub-scanning direction X while maintaining a predetermined speed relationship, and the light from the light source 44A of the carriage 44 is emitted through the second platen glass 42. The original document M is irradiated with light, and the light reflected by the original document M is reflected by the mirror 44B of the carriage 44 . Further, this light is reflected by the mirrors 45A and 45B of the optical system unit 45 and enters the CCD sensor 47 through the condenser lens 46. FIG. The CCD sensor 47 repeatedly reads the image of the document M in the main scanning direction Y (direction perpendicular to the sub-scanning direction X).

Further, the user places the document M on the document tray 33 of the document transport section 31 with the document transport section 31 closed, operates the start key of the operation section 12, and the control section 21 accepts the document reading instruction. shall be assumed. When the document M is detected by the second sensor, the control unit 21 sets the second mode, causes the document conveying unit 31 to convey the document M on the document tray 33 in accordance with the document reading instruction, and the reading unit 32 reads the document. Read the image of M. In the document transport section 31, the document M placed on the document tray 33 is pulled out by the feed roller 34, and the document M is moved in the sub-scanning direction through the upper surface of the first platen glass 41 by the registration roller 35 and each transport roller 36. Then, the document M is discharged to the document discharge tray 38 by the discharge roller 37 . In the reading section 32 , the carriage 44 and the optical system unit 45 are positioned at respective predetermined positions below the first platen glass 41 , and light from the light source 44 A of the carriage 44 is applied to the document M through the first platen glass 41 . Then, the light reflected by the document M is reflected by the mirrors 44B, 45A, and 45B and made incident on the CCD sensor 47 through the condensing lens 46, and the CCD sensor 47 repeatedly reads the image of the document M in the main scanning direction Y. Let

In both the first mode and the second mode, when the image of the document M is read by the reading section 32, the control section 21 temporarily stores image data representing the image of the document M in the image memory 17, and stores the image data. is stored in the storage unit 18, or the image of the document M indicated by the image data is formed on the recording paper P by the image forming unit 16. FIG.

Further, the image forming apparatus 10 of the present embodiment is provided with a crop processing function. This cropping process is a process of specifying and cropping one or more images of each document from the read image within the range read by the image reading unit 15 . In the image forming apparatus 10, the cropping process can be used regardless of whether the document conveying portion 31 and the document pressing cover 39 are opened or closed.

When the cropping process is performed with the document conveying portion 31 and the document holding cover 39 open, the user can omit opening and closing the document conveying portion 31 and the document holding cover 39, thereby improving work efficiency. In this case, the user opens the document transport section 31 and the document holding cover 39 to open the second platen glass 42, places a plurality of small documents (such as cards) on the second platen glass 42, and presses the start key. to operate. Based on this operation, the control unit 21 accepts the document reading instruction. In accordance with the document reading instruction, the control unit 21 sets the first mode while the document conveying unit 31 and the document holding cover 39 are kept open, and the reading unit 32 scans each document on the second platen glass 42 . to read the image of In the reading section 32, the carriage 44 and the optical system unit 45 are moved in the sub-scanning direction X while maintaining a predetermined speed relationship, and the light from the light source 44A of the carriage 44 is directed onto each document via the second platen glass 42. The light reflected by each document is reflected by the mirror 44B of the carriage 44 and the mirrors 45A and 45B of the optical system unit 45, and is incident on the CCD sensor 47 through the condenser lens 46. FIG. The CCD sensor 47 repeatedly reads in the main scanning direction Y over the range of the second platen glass 42, that is, the entire range in which the document can be read. The control unit 21 causes the image memory 17 to temporarily store the image data representing the read image of that range. The control unit 21 refers to the image data in the image memory 17 and acquires each pixel value indicating the brightness of each pixel in the read image. Based on the pixel values of pixels adjacent to each other, the control unit 21 detects the edges of the four sides of the image of each document, determines the size and position of the image of each document, and determines the size and position of each document included in the read image. Then, a known cropping process is performed to specify and cut out the image of each document, and image data representing the image of each document is obtained.

Here, when the illumination device 50 is installed around the image forming apparatus 10 (image reading section 15) as shown in FIG. When this is done, the light from the light source 51 of the illumination device 50 enters the second platen glass 42 and becomes disturbance light. For example, as shown in FIG. 5, disturbance light enters a specific region 61 of the second platen glass 42 . When the cropping process is executed in this state, the CCD sensor 47 of the reading unit 32 reads not only the image of each document on the second platen glass 42 but also the ambient light. The pixel value of each pixel fluctuates due to the influence of ambient light, and the four edges of the image of each document cannot be detected accurately, making it impossible to specify and cut out the image of each document included in the read image. There is a risk.

Therefore, in the present embodiment, the control unit 21 causes the reading unit 32 to perform pre-scanning when the cropping process is executed with the document conveying unit 31 and the document holding cover 39 open. Based on the read image read by the CCD sensor 47 of 32, it is determined whether or not it is possible to specify and cut out the image of each document included in the read image, that is, whether or not crop processing is possible. do. Then, the control unit 21 executes the cropping process when it is determined in the prior determination that the cropping process is possible. Further, when the control unit 21 determines that the crop processing is not possible, the control unit 21 controls the lighting device 50 to reduce the amount of light from the light source 51 of the lighting device 50, thereby reducing disturbance light incident on the second platen glass 42. Let The control unit 21 gradually reduces the amount of light from the light source 51 of the illumination device 50 until the disturbance light incident on the second platen glass 42 is sufficiently reduced to enable crop processing based on the read image.

Next, the flow of processing when executing crop processing in the image forming apparatus 10 will be described with reference to the flowchart shown in FIG. 6 and the like. FIG. 6 is a flow chart showing the flow of processing when crop processing is executed in the image forming system according to the first embodiment.

For example, when the user operates the GUI displayed on the display unit 11 to input an instruction to set the details of crop processing, the control unit 21 receives the instruction. In response to the instruction, the control unit 21 displays a selection screen on the display unit 11 for selecting whether or not to use the cropping function while the document conveying unit 31 and the document holding cover 39 are kept open. Display (S101). For example, the display unit 11 displays an open/close selection screen G1 as shown in FIG. This opening/closing selection screen G1 includes a message M1 prompting a user to select whether or not to use the cropping function with the document conveying section 31 and the document holding cover 39 kept open, an OK key K11, and an NG key K12. is displayed.

For example, when the user touches the NG key K12, the control unit 21 accepts an instruction to immediately execute the crop processing through the touch panel 13 based on the touch operation on the NG key K12 (S102 "NG"), and performs the crop processing. (S103).

In this case, for example, the user opens document transport section 31 and document holding cover 39, places a plurality of small documents (such as cards) on second platen glass 42, and closes document transport section 31 and document holding cover 39. Then, the NG key K12 is touch-operated. At this time, the control unit 21 executes the cropping process in accordance with the instruction to immediately execute the cropping process received in response to the touch operation. The control unit 21 causes the reading unit 32 to read the range of the second platen glass 42 , and causes the image memory 17 to temporarily store image data representing the read image of the read range. Further, the control unit 21 acquires the pixel values of the pixels forming the read image indicated by the image data in the image memory 17, and based on the pixel values of the pixels adjacent to each other, determines the image of each document in the read image. Four edges are detected to determine the size and position of each original image. Then, based on the determination result, the control unit 21 specifies the image of each document included in the read image, and executes crop processing for cropping the image of each document. The control unit 21 causes the storage unit 18 to store each image data representing the image of each document.

Therefore, when the control unit 21 receives a crop processing execution instruction from the user when the opening/closing selection screen G1 is displayed, the control unit 21 performs "crop processing based on a read image including disturbance light incident on the second platen glass 42". Crop processing is executed without performing "determining whether or not it is possible to Even if the user does not close the document conveying unit 31 and the document holding cover 39 and the reading unit 32 reads the range of the second platen glass 42 in that state, the control unit 21 does not read the read range. A process of specifying and extracting the image of each document from the image is executed. In this case, the image of each document cannot be specified from the read image, and a situation may occur in which the image of each document cannot be cut out.

Further, when the user touches the OK key K11 while the opening/closing selection screen G1 is displayed, the control unit 21 displays "Remove disturbance light incident on the second platen glass 42" based on the touch operation on the OK key K11. Judgment as to whether or not cropping processing based on the read image is possible" is accepted through the touch panel 13 ("OK" in S102). At this time, the control unit 21 causes the screen of the display unit 11 to display a message indicating that pre-scanning for making the determination is to be executed (S104). For example, the display unit 11 displays a message M2 as shown in FIG.

Upon seeing the message M2, the user opens the document conveying section 31 and the document holding cover 39 with respect to the second platen glass 42 on which each document is placed. The control unit 21 executes pre-scanning and causes the reading unit 32 to read the range of the second platen glass 42 (S105). In the reading unit 32, the carriage 44 and the optical system unit 45 are moved in the sub-scanning direction X while maintaining a predetermined speed relationship, and the light from the light source 44A of the carriage 44 is directed to the upper space via the second platen glass 42. , and the disturbance light incident on the second platen glass 42 is reflected by the mirror 44B of the carriage 44 and the mirrors 45A and 45B of the optical system unit 45, and is incident on the CCD sensor 47 through the condenser lens 46. . The CCD sensor 47 repeatedly reads the range of the second platen glass 42 in the main scanning direction Y. As shown in FIG. The control unit 21 causes the image memory 17 to store image data representing the read image within the range of the second platen glass 42 .

The control unit 21 acquires each pixel value indicating the brightness of each pixel in the read image indicated by the image data in the image memory 17, and sets the brightness to a preset brightness (predetermined brightness when ambient light is read). A region composed of each pixel having a pixel value equal to or higher than the brightness threshold indicating the value of the lightness is detected (S106). This area is the area on the second platen glass 42 where disturbance light is incident, and is a particularly bright area in the read image. That is, the controller 21 detects ambient light. For example, when the brightness of pixels is defined by 256 gradations, the brightness threshold is preset to about 150, and the brightness of each pixel in that area is 150 or more.

The control unit 21 counts the number of pixels forming the bright region in the read image, and determines whether or not the counted number of pixels is equal to or larger than a preset size threshold (S107). In other words, the control unit 21 determines the size of the bright area, and determines whether or not the determined size of the area is equal to or greater than a preset size. For example, the size threshold is set in advance to about 2% of the total number of pixels in the read image, that is, the number of pixels within the size of about 2% of the total area of the second platen glass 43 .

When the control unit 21 determines that the number of pixels forming the bright region is not equal to or larger than the size threshold value (S107 "No"), the region on the second platen glass 42 on which the disturbance light is incident is small. It is determined that crop processing is possible (S108). The control unit 21 causes the screen of the display unit 11 to display a message indicating that crop processing is possible (S109). For example, a message M3 as shown in FIG. 9 is displayed on the display unit 11 to notify the user that crop processing is possible.

At this time, the user sees the message M3, places a plurality of small documents (cards, etc.) on the second platen glass 42, and presses the start key while the document transport section 31 and the document holding cover 39 are open. to operate. The control unit 21 accepts an instruction to execute the cropping process through the touch panel 13 based on the operation of the start key. The control unit 21 executes the cropping process according to the instruction to execute the cropping process (S110). In this cropping process, the control section 21 causes the reading section 32 to read the image of each document on the second platen glass 42 . Then, the control unit 21 causes the image memory 17 to store the image data representing the read image of the range including each document on the second platen glass 42, and the brightness of each pixel in the read image represented by the image data in the image memory 17. Then, based on the pixel values of adjacent pixels, four edges of the image of each document are detected to determine the size and position of the image of each document. Furthermore, the control unit 21 specifies and cuts out the image of each document included in the read image. The control unit 21 causes the storage unit 18 to store each image data representing the image of each document.

On the other hand, when the control unit 21 determines that the number of pixels forming the bright area in the read image is equal to or larger than the size threshold (S107 "Yes"), the area on the second platen glass 42 where the ambient light is incident is Since it is wide, it is determined that crop processing is not possible (S111). At this time, the control unit 21 causes the screen of the display unit 11 to display a message indicating that the amount of light of the lighting device is to be reduced because the crop processing is not possible (S112). For example, a message M4 as shown in FIG. 10 is displayed on the screen of the display unit 11 to notify the user that the amount of light of the illumination device is to be reduced because the crop processing is not possible.

Then, the control unit 21 causes the short-range communication unit 14 to transmit a control signal instructing to reduce the amount of light to the illumination device 50 (S113). In the illumination device 50 , when the control signal is received by the short-range communication unit 54 , the control unit 55 controls the power supply unit 52 according to the instruction to reduce the light amount by the control signal to reduce the light amount of the light source 51 . For example, when the LED of the light source 51 is emitted by the power supply unit 52 by a PWM (Pulse Width Modulation) method, the control unit 55 controls the power supply unit 52 to shorten the light emission time of the LED and reduce the light intensity of the light source 51. reduce

Here, the control signal for instructing the reduction of the light amount transmitted by the control unit 21 sets the light amount of the light source 51 of the lighting device 50 to 3/4, 2/4, 1/4, or 0/4. It indicates that Every time the control unit 21 transmits the control signal, the light amount of the light source 51 of the lighting device 50 is sequentially reduced by 1/4, such as 3/4, 2/4, 1/4, and 0/4. The content indicated by the control signal is changed each time transmission is performed so that the amount of light from the light source 51 becomes 0 (the light source 51 is turned off) at the time of the second instruction. For the first time, the control unit 21 transmits a control signal for reducing the light amount of the light source 51 of the lighting device 50 to 3/4.

Thereafter, the control unit 21 determines whether or not the light intensity of the light source 51 of the illumination device 50 has become 0 (whether or not a control signal indicating the light intensity of the light source 51 to 0/4 has been transmitted) by the instruction to reduce the light intensity. (S114), if the light intensity of the light source 51 is not 0 (S114 "No"), return to S105, execute prescan again, cause the reading unit 32 to read the range of the second platen glass 42, Detecting an area composed of pixels having a pixel value equal to or higher than the brightness threshold in the read image within the range of the second platen glass 42 (S106), counting the number of each pixel constituting the bright area in the read image, It is determined whether or not the counted number of pixels is equal to or larger than the size threshold (S107).

When the control unit 21 determines that the number of pixels forming the bright region is not equal to or larger than the size threshold value (S107 "No"), the region on the second platen glass 42 on which the disturbance light is incident becomes narrow. , it is determined that crop processing is possible (S108). After that, crop processing is executed in the same manner as described above (S109, S110).

Further, when the control unit 21 determines that the number of pixels forming the bright area in the read image is still equal to or larger than the size threshold (S107 "Yes"), the disturbance light is incident on the second platen glass 42. Since the area is large, it is determined that crop processing is not possible (S111). In this case, the control unit 21 causes the screen of the display unit 11 to display again the message M4 indicating that the amount of light of the lighting device is to be reduced because the crop processing is not possible (S112). Then, the control unit 21 causes the short-range communication unit 14 to transmit a control signal indicating an instruction to further reduce the amount of light to the illumination device 50 (S113). When the control signal is received by the short-range communication unit 54 , the control unit 55 of the lighting device 50 controls the power supply unit 52 to further reduce the amount of light from the light source 51 .

Similarly, every time it is determined that the light quantity of the light source 51 of the illumination device 50 is not 0 due to the instruction to reduce the light quantity (S114 "No"), the process returns to S105 and repeats the processes of S105 to S113.

Here, when the control signal instructing the reduction of the light amount is transmitted for the fourth time, the control unit 21 determines that the light amount of the light source 51 of the lighting device 50 has become 0 (S114 "Yes"). ). In this case, the control unit 21 performs prescan again (S115), and detects an area composed of pixels having a pixel value equal to or higher than the brightness threshold in the read image within the range of the second platen glass 42 (S116). , it is determined whether or not the number of pixels forming the bright area in the read image is equal to or larger than the size threshold (S117).

If the number of pixels forming the bright area is not equal to or greater than the size threshold ("No" in S117), the control unit 21 determines that the cropping process is possible (S108), and the cropping process is possible. A message M3 to that effect is displayed on the screen of the display unit 11 (S109), and crop processing is executed (S110).

Further, when the control unit 21 determines that the number of pixels forming the bright area in the read image is equal to or larger than the size threshold (S117 "Yes"), even if the light amount of the light source 51 of the illumination device 50 is set to 0, It is determined that crop processing is not possible (S118). The control unit 21 displays a message indicating that the cropping process cannot be executed (it may be that the cropping process cannot be executed while the document holding cover 39 is open) on the screen of the display unit 11. is displayed (S119). After this, the process ends.

For example, the screen of the display unit 11 displays a message M5 as shown in FIG. As a result, the user is notified that the cropping process cannot be executed while the document holding cover 39 is open, and an illumination device other than the illumination device controlled by the image forming apparatus 10 is used. You are prompted to turn off the lights or close the curtains on the outside windows. For example, the user sees the message M5, turns off the other lighting device, or closes the curtain of the outside window, and restarts the process from S101.

As described above, in the first embodiment, pre-scanning is performed by the reading unit 32, and disturbance light incident on the second platen glass 42 is detected based on the read image read by the pre-scanning, so that crop processing can be performed. If it is determined that the cropping process is not possible, the amount of light from the light source 51 of the lighting device 50 is reduced. processing becomes possible.

In the first embodiment, each time it is determined that the cropping process is not possible, the amount of light from the light source 51 of the illumination device 50 is gradually reduced, and finally the light source 51 is turned off. When it is determined that crop processing is not possible for the first time, from the first time onwards, a control signal indicating the light intensity of the light source 51 to 0/4 (light intensity off) is transmitted to turn off the light source 51 immediately. can be That is, when the control unit 21 executes the first prescan and first determines that the crop processing is not possible, the control unit 21 transmits a control signal indicating that the light amount of the light source 51 of the lighting device 50 is off from the short-range communication unit 14 to the lighting device. Send to 50. When the control signal is received by the short-range communication unit 54 , the control unit 55 of the lighting device 50 stops the power supply unit 52 and turns off the light source 51 in response to this control signal. In this case, since it is not necessary to adjust the light amount of the light source 51, it is possible to use, as the light source 51, an illumination device such as an electric bulb or a fluorescent lamp that cannot adjust the light amount.

Further, when the control unit 21 determines that the cropping process is possible, the control unit 21 stores the light amount of the light source 51 of the lighting device 50 at this time in the storage unit 18, and determines that the cropping process is not possible at another opportunity. When it is determined, the amount of light previously determined to be capable of crop processing and stored is read from the storage unit 18, and a control signal indicating the amount of light is transmitted from the short-range communication unit 14 to the lighting device 50. may When the control signal is received by the short-range communication unit 54, the control unit 55 of the illumination device 50 controls the power supply unit 52 to adjust the light amount of the light source 51 to the light amount indicated by the control signal. As a result, it is possible to quickly adjust the amount of light from the light source 51 of the illumination device 50 to a level at which crop processing is possible. In addition, the amount of light from the light source 51 of the illumination device 50 fluctuates due to deterioration of the light source 51 over time. Therefore, the processing of S105 to S107 may be performed periodically, and the stored light intensity may be rewritten to the light intensity when it is determined that the crop processing is possible most recently.

In the first embodiment, it is determined that the crop processing is not possible when the number of pixels forming a bright area on which ambient light is incident in the read image is greater than or equal to the size threshold (S107 "Yes"). Each time (S111), pre-scanning is executed via S112 and S113 ("No" in S114, S105), but instead of this, the control unit 21 first determines that crop processing is not possible. Then, immediately after this determination, a state is set in which only the bright area in the read image is limited to the bright area, and only the bright area is continuously read by the reading unit 32, and the number of pixels constituting the bright area is set. The amount of light from the light source 51 of the illumination device 50 may be gradually reduced until it is determined that the size is no longer equal to or greater than the size threshold.

In this case, when the control unit 21 executes the first prescan and first determines that crop processing is not possible, the CCD sensor 47 of the reading unit 32 always reads only the bright area in the read image thereafter. The positions of the carriage 44 and the optical system unit 45 are adjusted and set, or the movement range of the carriage 44 and the optical system unit 45 in the sub-scanning direction X is limited and the carriage 44 and the optical system unit 45 are repeatedly moved back and forth. Then, in this state, the control unit 21 gradually reduces the light amount of the light source 51 of the lighting device 50 until it determines that the pixel value of each pixel in the bright area is less than the brightness threshold based on the output of the CCD sensor 47. . When the control unit 21 determines that the pixel value of each pixel in the bright area is less than the brightness threshold, it performs crop processing.
<Second embodiment>
Next, an image reading system according to the second embodiment will be described. As shown in FIG. 12, the image reading system Sy of the second embodiment differs from the image reading system Sy of the first embodiment in that a plurality of lighting devices 50 are provided. In the second embodiment, the image forming apparatus 10 controls multiple lighting devices 50 .

A plurality of lighting devices 50 are provided around the image forming apparatus 10 . When the document conveying section 31 of the image reading section 15 and the document pressing cover 39 are open, the light from the light source 51 of each lighting device 50 enters the second platen glass 42 and becomes disturbance light.

In the second embodiment as well, when receiving an instruction to execute crop processing, the control unit 21 first causes the reading unit 32 to perform pre-scanning, and based on the read image read by the CCD sensor 47 of the reading unit 32, performs a second scan. 2. Ambient light incident on the platen glass 42 is detected, and based on the detected ambient light, it is determined whether or not cropping is possible. Then, when the control unit 21 determines that the cropping process is possible, it executes the cropping process.

However, in the second embodiment, when the control unit 21 determines that crop processing is not possible, it selects the lighting device 50 closest to the image forming device 10 from among the plurality of lighting devices 50, and selects the lighting device 50. Control is performed to turn off the light source of the lighting device 50 .

Further, if it is not determined that cropping is possible after the light source of the selected lighting device 50 is turned off, it is determined that cropping is possible. From among the lighting devices 50, the lighting device 50 that is closest to the image forming device 10 next to the lighting device 50 that was recently turned off is sequentially selected, and the light source of the selected lighting device 50 is turned off sequentially. I do.

For example, the storage unit 18 of the image forming apparatus 10 stores an identifier table (not shown) in which the identifier IDs of the lighting apparatuses 50 are arranged in order with priority given to the lighting apparatus 50 closer to the image forming apparatus 10 . ing. The control unit 21 refers to the identifier table stored in the storage unit 18, sequentially reads out the identifier ID of each lighting device 50 from the one closest to the image forming device 10, and selects the lighting device 50 having the read identifier ID. Control is performed to sequentially select and turn off each lighting device 50 .

Next, processing when executing crop processing in the image forming system according to the second embodiment will be described. FIG. 13 is a flowchart showing the flow of processing when executing crop processing in the image forming system according to the second embodiment.

For example, when the user operates the GUI displayed on the display unit 11 to input an instruction to set the details of crop processing, the control unit 21 receives the instruction. In response to the instruction, the control unit 21 opens and closes the document feeder 31 and the document holding cover 39 as shown in FIG. The selection screen G1 is displayed on the display unit 11 (S201).

For example, when the user touches the NG key K12, the control unit 21 accepts a crop processing execution instruction through the touch panel 13 based on the touch operation on the NG key K12 (S202 "NG"), and executes the crop processing. (S203).

In this case, for example, the user opens document transport section 31 and document holding cover 39, places a plurality of small documents (such as cards) on second platen glass 42, and closes document transport section 31 and document holding cover 39. Then, the NG key K12 is touch-operated. At this time, the control unit 21 executes the cropping process in accordance with the cropping process execution instruction received in response to the touch operation.

Further, when the user touches the OK key K11 while the opening/closing selection screen G1 is displayed, the control unit 21 displays "Remove disturbance light incident on the second platen glass 42" based on the touch operation on the OK key K11. Judgment as to whether or not cropping processing based on the read image is possible" is accepted through the touch panel 13 ("OK" in S202). At this time, the control unit 21 causes the screen of the display unit 11 to display a message M2, for example, as shown in FIG.

Upon seeing the message M2, the user opens the document conveying section 31 and the document holding cover 39 with respect to the second platen glass 42 on which each document is placed. The control unit 21 executes pre-scanning and causes the reading unit 32 to read the range of the second platen glass 42 (S205). The control unit 21 causes the image memory 17 to store image data representing the read image within the range of the second platen glass 42 .

The control unit 21 acquires each pixel value indicating the brightness of each pixel in the read image indicated by the image data in the image memory 17, and obtains each pixel having a pixel value equal to or higher than a brightness threshold indicating brightness set in advance. The configured area is detected (S206).

The control unit 21 counts the number of pixels forming the bright region in the read image, and determines whether or not the counted number of pixels is equal to or greater than a preset size threshold (S207).

When the control unit 21 determines that the number of pixels forming the bright region is not equal to or greater than the size threshold value (S207 "No"), the region on the second platen glass 42 where the ambient light is incident is small. It is determined that crop processing is possible (S208). The control unit 21 displays, for example, a message M3 as shown in FIG. 9 on the screen of the display unit 11 indicating that the cropping process is possible (S209).

At this time, the user sees the message M3, places a plurality of small documents (cards, etc.) on the second platen glass 42, and presses the start key while the document transport section 31 and the document holding cover 39 are open. to operate. The control unit 21 accepts an instruction to execute the cropping process through the touch panel 13 based on the operation of the start key. The control unit 21 executes the cropping process according to the instruction to execute the cropping process (S210).

On the other hand, when the control unit 21 determines that the number of pixels forming the bright region in the read image is equal to or larger than the size threshold (“Yes” in S207), the region on the second platen glass 42 where the ambient light is incident is Since it is wide, it is determined that crop processing is not possible (S211). At this time, the control unit 21 causes the screen of the display unit 11 to display a message M4 indicating that one of the plurality of lighting devices 50 is to be turned off because crop processing is not possible (S212).

The control unit 21 refers to the identifier table stored in the storage unit 18, selects and reads the identifier ID of the lighting device 50 closest to the image forming device 10, and obtains an identifier indicating the selected lighting device 50. The control signal indicating the ID and turning off the light source is transmitted from the short-range communication unit 14 to the selected lighting device 50 (S213).

In each lighting device 50, when the control signal is received by the short-range communication unit 54, the control unit 55 determines whether or not the identifier ID indicated by the control signal matches the identifier ID of its own lighting device 50. If they do not match, turning off the light source indicated by the control signal is invalidated, and if they match, turning off the light source indicated by the control signal is enabled, and the power supply unit 52 is controlled to turn off the light source 51 . Thereby, the light source of the illumination device 50 closest to the image forming apparatus 10 is turned off.

After that, the control unit 21 determines whether or not the transmission of the identifier ID and the control signal indicating turning off of the light source has ended for all the identifier IDs of the lighting devices 50 in the identifier table (S214). If not ("No" in S214), the process returns to S205, pre-scanning is performed again, the range of the second platen glass 42 is read by the reading unit 32, and the brightness threshold in the read image of the range of the second platen glass 42 is determined. A region composed of pixels having pixel values equal to or larger than the size threshold is detected (S206), the number of pixels forming the bright region in the read image is counted, and the counted number of pixels is equal to or greater than the size threshold. It is determined again whether or not there is (S207).

Here, when the control unit 21 determines that the number of pixels forming the bright region is not equal to or larger than the size threshold (“No” in S207), the region on the second platen glass 42 where the ambient light is incident is Since it has become narrower, it is determined that crop processing is possible (S208). After that, crop processing is executed in the same manner as described above (S209, S210).

Further, when the control unit 21 determines that the number of pixels forming the bright area in the read image is equal to or larger than the size threshold (S207 "Yes"), the area on the second platen glass 42 where disturbance light is incident is wide, it is determined that crop processing is not possible (S211). In this case, the control unit 21 causes the screen of the display unit 11 to display again the message M4 indicating that the amount of light of the lighting device is to be reduced because the crop processing is not possible (S212). Then, the control unit 21 refers to the identifier table stored in the storage unit 18 to refer to the illumination device 50 that is the closest to the image forming apparatus 10 after the lighting device 50 that has been turned off. , the identifier ID of the lighting device 50 is selected and read, and the identifier ID indicating the selected lighting device 50 and the control signal indicating turning off of the light source are transmitted from the short-range communication unit 14 to the lighting device 50 (S213).

In each lighting device 50, similarly to the above, when the control signal is received by the short-range communication unit 54, the control unit 55 determines whether the identifier ID indicated by the control signal matches the identifier ID of its own lighting device 50. If they match, turning off the light source indicated by the control signal is validated, and the power supply unit 52 is controlled to turn off the light source 51 . As a result, the light source of the illumination device 50 that is the second closest to the image forming apparatus 10 is turned off.

Likewise, if the transmission of the identifier ID and the control signal indicating turning off of the light source has not been completed for all of the identifier IDs of the lighting devices 50 in the identifier table (S214 "No"), the process returns to S205. The process of S213 is repeated.

As a result, each time the determination that the cropping process is not possible is repeated, the lighting device 50 closer to the image forming apparatus 10 is sequentially selected from among the lighting devices 50, and the light source 51 of the selected lighting device 50 is selected. are turned off sequentially.

When transmission of the identifier ID and the control signal indicating turning off of the light source for all the identifier IDs of the lighting devices 50 in the identifier table is completed (S214 "Yes"), the control unit 21 executes prescan again (S215). . Then, the control unit 21 detects an area composed of pixels having a pixel value equal to or greater than the brightness threshold in the read image within the range of the second platen glass 42 (S216), and detects each pixel constituting the bright area in the read image. is greater than or equal to the size threshold (S217).

If the number of pixels forming the bright area is not equal to or greater than the size threshold ("No" in S217), the control unit 21 determines that cropping is possible (S208), and the cropping is possible. A message M3 to that effect is displayed on the screen of the display unit 11 (S209), and crop processing is executed (S210).

Further, when the control unit 21 determines that the number of pixels forming the bright area in the read image is equal to or larger than the size threshold (S217 "Yes"), even if the light sources 51 of all the lighting devices 50 are turned off, It is determined that crop processing is not possible (S218). The control unit 21 displays, for example, the message M5 indicating that the cropping process cannot be executed (it may be that the cropping process cannot be executed while the document holding cover 39 is open). 11 screen (S219). After this, the process ends.

After seeing the message M5, the user turns off a lighting device other than the lighting device controlled by the image forming apparatus 10, or closes the curtain of the outside window, and then executes the processing from S201. let it resume.

As described above, in the second embodiment, pre-scanning is performed by the reading unit 32, and disturbance light incident on the second platen glass 42 is detected based on the read image read by the pre-scanning, so that crop processing can be performed. If it is determined that crop processing is not possible, the light sources 51 of the lighting devices 50 are turned off in order from the one closer to the image forming apparatus 10, so that the user operates the lighting devices, for example. Crop processing can be performed without the work of .

In the second embodiment, the light source 51 of each lighting device 50 is simply selected and turned off. Therefore, as the light source 51, it is possible to apply a lighting device such as a light bulb or a fluorescent lamp that cannot adjust the amount of light. Become.

Further, when the control unit 21 determines that the crop processing is possible, the control unit 21 stores the identifier ID of each lighting device 50 whose light source 51 is turned off in the storage unit 18, and stores the identifier ID in the storage unit 18 at another time. When the cropping function is set again and pre-scanning is performed and it is determined that the cropping process is not possible, the identifier ID of each lighting device 50 when it was previously determined that the cropping process is possible is stored in the storage unit. 18 , and transmit the identifier ID of these lighting devices 50 and the control signal indicating turning off of the light source from the short-range communication unit 14 to all the lighting devices 50 . When the control signal is received by the short-range communication unit 54, the control units 55 of all the lighting devices 50 determine whether each identifier ID indicated by the control signal includes the identifier ID of its own lighting device 50. If it is not included, turning off the light source indicated by the control signal is invalidated, and if it is included, turning off the light source indicated by the control signal is enabled, and the power supply unit 52 is controlled to turn off the light source. 51 is turned off. This allows the light source 51 of each lighting device 50 to be selected and turned off immediately to enable cropping.

In the second embodiment, it is determined that the cropping process is not possible because the number of pixels forming a bright area on which ambient light is incident in the read image is greater than or equal to the size threshold ("Yes" in S207). Each time (S211), pre-scanning is executed via S212 and S213 ("No" in S214, S205), but instead of this, the control unit 21 first determines that crop processing is not possible. Immediately after this determination, a state is set such that only the bright area in the read image is continuously read by the reading unit 32, and the number of pixels forming the bright area is determined. The above-described control may be performed to turn off the light sources 51 of the lighting devices 50 in order from the one closest to the image forming device 10 until it is determined that the size is no longer equal to or larger than the size threshold.

In this case, when the control unit 21 executes the first prescan and first determines that the cropping process is not possible, the CCD sensor 47 of the reading unit 32 always reads only the bright area in the read image. , the positions of the carriage 44 and the optical system unit 45 are adjusted and set, or the range of movement of the carriage 44 and the optical system unit 45 in the sub-scanning direction X is limited, and the carriage 44 and the optical system unit 45 are repeatedly moved back and forth. until it is determined that the pixel value of each pixel in the area is less than the brightness threshold value based on the above control to turn off the light source 51 of each lighting device 50 in order.

In each of the above-described embodiments, an image forming apparatus is taken as an example, but the image reading system of the present invention can also be applied to an image reading apparatus such as a facsimile apparatus, or a system that combines a PC, a scanner, and the like. It is possible.

Also, the configuration and processing of each of the above embodiments described with reference to FIGS. 1 to 13 are merely examples of the present invention, and are not intended to limit the present invention to the configuration and processing.

10 Image forming apparatus 11 Display unit 12 Operation unit 13 Touch panel 14 Near field communication unit 15 Image reader 16 Image forming unit 17 Image memory 18 Storage unit 19 Control unit 21 Control unit 50 Lighting device 51 Light source 52 Power supply unit 54 Near field communication unit 55 control unit Sy image reading system

Claims (11)

An image reading device,
a translucent manuscript table on which a manuscript is placed;
a document holding cover that is openable and closable with respect to the document platen and covers the document platen and the document placed on the document platen when closed;
an image reading unit that irradiates a document placed on the document table with light through the document table and reads an image of the document through the document table;
a control unit that controls the image reading unit and controls at least one illumination device that is provided around the image reading unit and is separate from the image reading device;
The control unit has a crop processing function of causing the image reading unit to perform reading, and specifying and cropping an image of the document on the document platen included in the read image read by the image reading unit. and when the cropping process is executed with the document holding cover open, prescanning is performed by the image reading section, and the document is incident on the document table based on the read image read by the image reading section. detecting disturbance light from the source, determining whether or not it is possible to specify and cut out an image of the document contained in the read image based on the detected disturbance light, and specifying the image of the document; an image reading device that controls the illumination device to reduce or set the light amount of the illumination device to zero when it is not possible to extract the image by 2. The image reading apparatus according to claim 1, wherein the control unit executes the crop processing when determining that the image of the document can be specified and cropped. 3. When determining that it is impossible to specify and cut out the image of the document, the control unit controls and turns off the illumination device, and sets the light amount of the illumination device to 0. The image reading device according to . The control unit
controlling the lighting device to reduce the amount of light of the lighting device when it is determined that it is impossible to specify and cut out the image of the document;
causing the image reading unit to perform prescan again, detecting disturbance light incident on the document table based on the read image read by the image reading unit;
determining whether or not it is possible to specify and cut out the image of the document included in the read image based on the detected disturbance light, and determine whether the image of the document can be specified and cut out; 3. The image reading apparatus according to claim 1, further reducing the amount of light of said lighting device by controlling said lighting device when said determination is made. If the control unit determines that it is not possible to specify and cut out the image of the document, after controlling the lighting device to reduce the light amount of the lighting device, the image reading unit controls the reading Continuous reading is performed only on an area corresponding to the image portion detected as the disturbance light in the image, and the image of the document is specified based on the disturbance light detected from the read image obtained by the continuous reading. 3. The image reading apparatus according to claim 1, wherein the lighting device is controlled to reduce the amount of light of the lighting device until it is determined that the image can be cut out. When the control unit reduces the amount of light of the illumination device until it becomes possible to specify and crop the image of the document, the reduced amount of light is stored, and then the cropping process is performed again. 6. The image reading apparatus according to claim 5, wherein when executed, the light amount of said lighting device is set to said stored light amount. The control unit
controlling a plurality of said lighting devices;
The order of the illumination devices is obtained in advance, in which the illumination device located closer to the image reading unit is preferentially set, and based on the detected disturbance light, the image of the document included in the read image is determined. 2. When it is determined that the image cannot be specified and clipped, the lighting device closest to the image reading unit is selected from among the lighting devices, and the selected lighting device is turned off. 3. The image reading device according to claim 2. The control unit selects the lighting device closest to the image reading unit from among the lighting devices when it is determined that it is impossible to specify and cut out the image of the document based on the detected ambient light. Then, the selected illumination device is turned off, prescanning is performed again by the image reading unit, and disturbance light incident on the document table is detected based on the read image read by the image reading unit. and determining whether or not it is possible to specify and cut out the image of the document included in the read image based on the detected ambient light, and specify and clip the image of the document. 8. The image reading apparatus according to claim 7, wherein when it is determined that the lighting apparatus is not possible, the lighting apparatus next closest to the image reading unit is selected from among the lighting apparatuses, and the selected lighting apparatus is turned off. . If the control unit determines that it is impossible to specify and cut out the image of the document based on the detected disturbance light, after controlling the lighting device to reduce the light amount of the lighting device, The image reading unit continuously reads only the area corresponding to the image portion detected as the disturbance light in the read image, and based on the disturbance light detected from the read image obtained by the continuous reading. 8. The image reading apparatus according to claim 7, wherein said illumination devices are sequentially turned off from the one closer to said image reading unit until it is determined that it is possible to specify and cut out the image of said document. When the control unit turns off the lighting device until the image of the document can be specified and cropped, the lighting device that has been turned off is stored, and then the cropping process is executed again. 10. The image reader of claim 9, wherein the stored lighting device is turned off when the lighting device is turned off. an image reading device; and at least one lighting device provided around the image reading device,
The image reading device is
a translucent manuscript table on which a manuscript is placed;
a document holding cover that is openable and closable with respect to the document platen and covers the document platen and the document placed on the document platen when closed;
an image reading unit that irradiates a document placed on the document table with light through the document table and reads an image of the document through the document table;
a control unit that controls the image reading unit and the lighting device,
The control unit has a crop processing function of causing the image reading unit to perform reading, and specifying and cropping an image of the document on the document platen included in the read image read by the image reading unit. and when the cropping process is executed with the document holding cover open, prescanning is performed by the image reading section, and the document is incident on the document table based on the read image read by the image reading section. detecting disturbance light from the source, determining whether or not it is possible to specify and cut out an image of the document contained in the read image based on the detected disturbance light, and specifying the image of the document; 1. An image reading system for controlling the illumination device to reduce or set the light amount of the illumination device to zero when the image cannot be cut out by using the above method.

Images