JP5655330B2 - Image reading apparatus and image forming apparatus having the same - Google Patents

Description

  The present invention includes an image reading device such as an image scanner for reading an image of an original (an image reading unit or a single image reading device mounted in an image forming apparatus such as a digital copying machine or a facsimile machine), and the image reading device. The present invention relates to an image forming apparatus.

As the image reading apparatus as described above, by detecting the thickness of the entire original, an area having a thickness different from the thickness of the original is specified on the entire surface of the original, and the area (specific area of the original) Is known that uses a technology that reads only the image (for example, reads only the image of the destination sticker attached to the envelope based on the thickness detection information of the entire document).
In such an image reading apparatus, when an original is automatically fed to a reading position (contact glass or the like) by an ADF (automatic document feeder) and an image of the original is read (during DF reading), a document transport path By detecting the thickness of the entire document using a transmissive or reflective sensor array disposed in the area, an image of a specific area, which is an area having a thickness different from the thickness of the document, is obtained on the entire surface of the document. Can be read.

  However, the thickness of the entire document cannot be detected when reading the image of the document set at the reading position by the pressure plate (when reading the pressure plate). That is, when the ADF is not provided, there is a problem that a function of reading only an image in a specific area of the document cannot be realized. In addition, when a thick book is used as a document, there is a problem that the above function cannot be realized in the first place for a document that cannot be transported by ADF.

Therefore, in order to solve the problem, it is conceivable to use the technique disclosed in Patent Document 1.
In Patent Document 1, the thickness of the entire original is detected from the light transmittance of the original obtained by irradiating the original with light for the purpose of preventing set-off at the time of reading the image of the original. A configuration for setting a reading condition that prevents a shift is disclosed.

However, even the one described in Patent Document 1 cannot solve the problem that it is impossible to read only an image in a specific area of a document.
The present invention has been made in view of the above points, and an object of the present invention is to detect only the image of a specific area of a document by detecting the thickness of the entire document even when reading a pressure plate. To do.

In order to achieve the above object, the present invention provides an image reading apparatus and an image forming apparatus including the same.
An image reading apparatus according to the present invention includes an image reading unit that scans an original set on the upper surface of a contact glass from the lower surface side of the contact glass to read an image, and a reading condition setting that sets a reading condition by the image reading unit. An image reading apparatus comprising: a document thickness detecting unit configured to scan a document set on the upper surface of the contact glass from a lower surface side of the contact glass and detect a thickness of the document; An area discriminating unit for discriminating an area having a thickness different from the thickness of the original document on the entire surface of the original document based on the thickness information indicating the thickness distribution of the entire original document to be detected; the setting means, comprising means for setting a condition of the reading for each region including a region of been the different thicknesses determined by the area determination means Than is.

Further, it may be as shown in any one of the following (1) to (5).
(1) The reading condition setting means sets only the thickest area as the reading area when there is an area with the different thickness as a result of the determination by the area determining means.
(2) Threshold value storage means for storing and holding threshold values for specifying the areas having different thicknesses is provided, and the reading condition setting means has the areas of different thicknesses as a result of determination by the area determination means. In this case, only a region having a thickness exceeding the threshold value is set as a reading region.

(3) Threshold value storage means for storing and holding threshold values for specifying the areas having different thicknesses is provided, and as a result of the determination by the area determination means, the reading condition setting means has areas of different thicknesses. In this case, the threshold value is added to the thickness of the region having the smallest thickness, and only the region having a thickness exceeding the added value is set as the reading region.
(4) Threshold storage means for storing and holding a threshold value for specifying the areas having different thicknesses and a limit value for representing the thickness range of the reading area is provided, and the reading condition setting means is configured to detect the area. As a result of the determination by the means, if there are areas with different thicknesses, a thickness area whose difference from the threshold is within the limit value is set as a reading area.

(5) Threshold storage means is provided for storing and holding a threshold value for specifying the areas having different thicknesses and a limit value for representing the thickness range of the reading area, and the reading condition setting means has the area discrimination. As a result of discrimination by means, if there are areas with different thicknesses, the threshold value is added to the thickness of the area with the smallest thickness, and the difference from the added value is within the limit value. The thickness area is set as the reading area.

In addition, as a reading mode by the image reading unit, a normal reading mode for reading an image of the entire surface of the original or a specific information reading mode for reading an image of an area having a different thickness is set by an instruction from the outside. Read mode setting means is provided, and when the normal read mode is set by the read mode setting means, the read condition setting means sets the read conditions for the entire surface of the original, and the read mode When the specific information reading mode is set by the setting unit, the reading condition may be set for each region including the regions having the different thicknesses determined by the region determining unit.

  An image forming apparatus according to the present invention includes the above-described image reading device, and performs image forming processing based on image data read by the image reading unit of the image reading device.

According to the present invention, the image reading apparatus or the image forming apparatus including the same scans a document set on the upper surface of the contact glass from the lower surface side of the contact glass, detects the thickness of the entire document, Based on the thickness information indicating the thickness distribution , an area having a thickness different from the thickness of the original is determined on the entire surface of the original, and a reading condition (for each area including the different thickness area) is determined. By setting (whether reading is necessary), it is possible to detect only the image of a specific area of the original (the area having the different thickness) by detecting the thickness of the entire original even when reading the pressure plate.

1 is a diagram illustrating a schematic configuration example of an image reading apparatus according to an embodiment of the present invention. FIG. 2 is a block diagram illustrating a system configuration example of the image reading apparatus illustrated in FIG. 1. It is explanatory drawing for demonstrating the method to specify the thickness part exceeding the reference value of a document as a reading area. It is another explanatory drawing for demonstrating the method similarly. It is a flowchart which shows an example of the reading process at the time of specific information reading mode setting by CPU17 of FIG. FIG. 4 is a diagram showing an example of the relationship between the thickness distribution of the entire document shown in FIG. 3C and a plurality of thickness levels determined from the distribution.

Hereinafter, embodiments for carrying out the present invention will be specifically described with reference to the drawings.
The following embodiments have the following characteristics when reading an image of a region having a thickness different from the thickness (thickness) of the original on the entire surface of the original. That is, the thickness of the entire document is detected by scanning the document set on the upper surface of the contact glass from the lower surface side of the contact glass, and the specific area (the entire surface of the document is detected from the distribution of the thickness of the entire document. The above is characterized in that a reading condition is set for each region including a region having a thickness different from the thickness of the document, and the image of the document is read according to the condition.
Therefore, the feature will be specifically described with reference to FIGS.

First, a basic configuration of an image reading apparatus and an original image reading operation according to an embodiment of the present invention will be described with reference to FIG.
FIG. 1 is a diagram showing a schematic configuration example of an image reading apparatus according to an embodiment of the present invention.
The image reading apparatus includes a contact glass 1 that is a transparent plate member on which a document P is set, and a pressure plate 2 that can be opened and closed with respect to the upper surface of the contact glass 1. Further, below the contact glass 1, a reflector (reflecting mirror) 3, 4, an exposure lamp (illumination lamp) 5, and an original thickness sensor array 6 each having a length in the main scanning direction which is the width direction thereof are respectively provided. I have. The reflection plates 3 and 4 and the exposure lamp 5 are optical systems and are mounted on a carriage. Instead of the pressure plate 2, it is possible to provide an ADF that also functions as a pressure plate.

  In such an image reading apparatus, when the reading operation is performed, after the pressure plate 2 is opened by the user and the document P is set on the contact glass 1, the document reading button on the operation unit 20 (see FIG. 2) described later is used. When the start of an image reading operation (hereinafter simply referred to as “reading operation”) of the document P is instructed by pressing, the document thickness sensor array (hereinafter simply referred to as “document thickness sensor”) 6, which is a reflective sensor array, is displayed. By moving the contact glass 1 in the sub-scanning direction, which is the longitudinal direction, and scanning the document P set (placed) on the upper surface of the contact glass 1 from the lower surface side of the contact glass 1 by the document thickness sensor 6. Then, the thickness of the entire document P is detected, and the thickness distribution is acquired.

  Thereafter, the lower surface (image surface) of the document set on the contact glass 1 is moved by the exposure lamp 5 while moving the exposure lamp 5 and the reflectors 3 and 4 in the sub-scanning direction at different speeds so that the optical path length does not change. By illuminating, the reflected light image from the image surface is sequentially sent to the later-described CCD 11 (see FIG. 2) via the reflectors 3 and 4, and the image of the original P is read.

  Here, the thickness detection of the entire document P using the document thickness sensor 6 can be performed by using a known technique (for example, see Patent Document 1). For example, all the light emitting portions of the document thickness sensor 6 moving in the sub-scanning direction are caused to emit light to sequentially irradiate the entire document, and the reflected light from the entire document P is sequentially received by all the light receiving portions of the document thickness sensor 6. By receiving light, the light transmittance at each position can be obtained from the ratio of the light emission amount and the light reception amount at each position of the entire document P, and the thickness of the entire document P can be detected from each light transmittance. .

Next, the system configuration of the image reading apparatus shown in FIG. 1 will be described with reference to FIG.
FIG. 2 is a block diagram illustrating a system configuration example of the image reading apparatus.
In this image reading apparatus, a CCD 11, an IPU (image processing unit) 12, an image storage device 13, a reading control unit 14, an original thickness sensor 6, a RAM 15, and a nonvolatile memory 16 are controlled by a CPU 17 through a bus 18.

The CPU 17 is a microcomputer incorporating a ROM in which a program is stored, and executes the program and controls a reading operation.
As a result, the reading control unit 14 drives the motor 19 and a driving mechanism (not shown) to move the document thickness sensor 6 in the sub-scanning direction, while driving the document thickness sensor 6. 6, by scanning the original P set on the upper surface of the contact glass 1, the thickness information of the original P is continuously captured and stored in the RAM 15.

  Further, the reading control unit 14 drives the motor 19 and a driving mechanism (not shown) to turn on the exposure lamp 5 while moving the exposure lamp 5 and the like, so that the document P set on the contact glass 1 is turned on. A reflected light image from the image plane is obtained by illuminating (scanning) the image plane. Since the reflected light is converted into an electronic signal (analog signal) by the CCD 11, an appropriate image processing is performed on the signal by the IPU 12, and then stored in the image storage device 13 as image data (digital signal). To do.

The image storage device 13 is a mass storage means such as an HDD (Hard Disk Device) for storing various data such as image data.
The nonvolatile memory 16 is a storage unit that stores and holds information such as a threshold value described later. The non-volatile memory 16 functions as a threshold storage unit.
The operation unit 20 includes an operation key and a display for inputting a setting value to be described later and a request for the reading control unit 14 and the like by a user operation.

  Here, the CCD 11, the IPU 12, the image storage device 13, the reading control unit 14, the RAM 15, the CPU 17, the motor 19, and the optical system described with reference to FIG. 1 constitute an image reading unit. Further, the reading control unit 14 and the CPU 17 function as reading condition setting means and reading mode setting means. Further, the document thickness sensor 6, the reading control unit 14, the CPU 17, and the motor 19 function as document thickness detecting means. The reading control unit 14 and the CPU 17 function as an area determination unit.

Next, the flow of processing related to the present invention by the image reading apparatus shown in FIG. 2 will be described with reference to FIGS.
3 and 4 are explanatory diagrams for explaining a method of specifying (recognizing) a thickness portion exceeding a reference value (threshold value) of a document as a reading region.

  FIG. 3A shows the positional relationship between the original P with a specific information sticker S such as an address sticker attached, the contact glass 1 on which the original P is set, and the original thickness sensor 6. It is shown from the upper surface side of the apparatus. FIG. 3B shows the positional relationship including the pressure plate 2 from the front side of the image forming apparatus. FIG. 3C shows the entire original P obtained by scanning the original P set on the upper surface of the contact glass 1 from the lower side of the contact glass 1 by moving the original thickness sensor 6 in the sub-scanning direction A. This shows the relationship between the thickness distribution and a specific area (area having a thickness different from that of the original on the entire surface of the original P) and a threshold value (reference value) VL2. In this figure, for the sake of convenience, it is shown in one dimension, but in reality, it takes a two-dimensional pressure distribution.

  4A shows a document P including a specific information sticker S in which the document thickness sensor 6 moves and scans in the sub-scanning direction A to detect the thickness, and FIG. 4B shows the thickness detection. 2 shows a state in which the thickness information (sensor data) indicating the thickness distribution (thickness distribution for each area) of the entire document acquired by the above is developed on the RAM 15 of FIG. 4A and 4B, the position of the information sticker S attached to the document P is different from that in FIGS. 3A and 3B for convenience of illustration.

  FIG. 5 is a flowchart showing an example of reading processing when the specific information reading mode is set by the CPU 17 of FIG. In this process, the CPU 17 in FIG. 2 measures the thickness distribution of the entire original P among the originals P including the specific information sticker S shown in FIG. 3 and FIG. This is a process of specifying only S as a reading area and reading only the image of the specific information sticker S, and is described in detail below.

2 sets the specific information reading mode according to the instruction from the operation unit 20, and then starts the reading operation according to the instruction to start the reading operation from the operation unit 20, and notifies the reading control unit 14 of the start of control. .
Upon receiving the notification, the reading control unit 14 first moves the document thickness sensor 6 in the sub-scanning direction A by driving the motor 19 or the like, for example, as shown in FIG. The original thickness sensor 6 scans the original P on the contact glass 1 to detect the thickness of the entire original P, and obtains the thickness distribution of the entire original P.

Thickness information indicating the thickness distribution of the entire document P (thickness distribution for each area) acquired as a result of the thickness detection of the entire document P is stored on the RAM 15 as shown in FIG. 4B, for example. Expand and hold.
Next, the process proceeds to step S102, and based on the thickness information held on the RAM 15, an area (specific area) having a thickness different from the thickness of the original is determined on the entire surface of the original P. That is, the thickness level is determined from the thickness information, and the thickness region is divided according to the level. For example, as shown in FIG. 6, the thickness region is separated by treating the portion included from the lower limit to the upper limit of the specific thickness value as an equivalent region having a thickness value rounded as an equivalent thickness level region. Realized.

FIG. 6 is a diagram showing an example of the relationship between the thickness distribution of the entire document and a plurality of thickness levels (“VL0”, “VL1”, “VL2” in this example) determined from the distribution. In FIG. 6, for the sake of convenience, it is shown in one dimension, but in reality, it takes a two-dimensional pressure distribution.
The reading control unit 14 divides the thickness area, and then proceeds to step S103, and among the divided thickness areas, the specific area shown in FIG. 3B (thickest area in this example). The specific information sticker S that is an area that exceeds the reference value VL2 for specifying is set (specified) as a reading area. In step S102, an area having the maximum thickness level (thickest area) can be cut out, and the maximum area can be set as a reading area in step S103.

  The reading control unit 14 finally proceeds to step S104, controls the motor 19 to move the exposure lamp 5 and the like, and turns on the exposure lamp 5 so that the lower surface of the document P set on the contact glass 1 is turned on. By illuminating, the reflected light image from the lower surface is read by the CCD 11 and stored in the image storage device 13 as image data, and the reading operation is completed. At this time, the IPU 12 sets the reading condition such that the image data of the reading area (reading target range) set previously is cut from the image data of the entire surface of the read document P, thereby setting the reading area. Only the image data of the power image area portion can be read. It is also possible to set other reading conditions such as reading resolution for the reading area, and to read only the image data of the image area portion to be set as the reading area under the reading condition. The read image image data can be printed (image formation) as a visible image on a printing medium such as paper by transmitting it to an external image forming apparatus such as a printer (not shown).

  Here, as the reference value, for example, a preset value (threshold value) or a preset value (threshold value) is added to the value of the lowest level (thickness of the region having the smallest thickness). Is given as a value. In the latter case, it is preferable to add a threshold value to the thickness of the region with the smallest thickness and set only the region having a thickness exceeding the added value as the reading region. The above threshold value is input from the outside, for example, from the user through the operation unit 20 as a UI (user interface), or is given as a fixed value, and is stored and held in the nonvolatile memory 16. The reading conditions are also input from the outside and stored in the nonvolatile memory 16.

  Note that the limit value for representing the thickness range of the reading area is also input through the operation unit 20 or given as a fixed value, and can be stored and held in the nonvolatile memory 16. In this case, it is possible to set a thickness region in which a difference with respect to the threshold value is within the limit value as a reading region. Alternatively, the threshold value can be added to the thickness of the region with the smallest thickness, and a region having a thickness within a limit value with respect to the value after the addition can be set as the reading region.

Further, in the example of the processing described with reference to FIG. 5, a document with one specific information sticker is used, but if a document with a plurality of specific information stickers is used, each piece of specific information is used. All the stickers can be set as a reading area.
Further, if a plurality of specific information stickers having different thicknesses are attached to the document, the specific information sticker corresponding to the area exceeding the reference value (or the area having the maximum thickness level) is set as the reading area. You can also. In this case, the reading condition can be set for each region having the same thickness.

As described above, the image reading apparatus of this embodiment moves the document thickness sensor in the sub-scanning direction which is the longitudinal direction of the contact glass 1, and the document set on the upper surface of the contact glass is moved to the document thickness sensor. By scanning from the lower surface side of the contact glass, the thickness of the entire document is detected, and the thickness on the entire surface of the document is different from the thickness of the document based on the thickness information indicating the thickness distribution. By determining the reading area (reading necessity) for each area including the areas having different thicknesses , the thickness of the entire original is detected even when reading the pressure plate. It is possible to read only the image in the area (specific area of the document).

  In the image reading apparatus of this embodiment, as a reading mode, in addition to the specific information reading mode for reading an image of an area having a different thickness, a normal reading mode for reading an image on the entire surface of the document is externally set. It can be set by instructions. When the normal reading mode is set, the reading condition is set for the entire surface of the document.

  The embodiment in which the present invention is applied to the image reading apparatus has been described above. However, the present invention is not limited to this, and the present invention is also applied to various image forming apparatuses such as a digital copying machine, a facsimile machine, and a printer equipped with the image reading apparatus. Is possible. Accordingly, the image forming apparatus main body can print the image data from the image reading apparatus on the print medium as a visible image.

  As is apparent from the above description, according to the present invention, it is possible to detect only the image of a specific area of the document by detecting the thickness of the entire document even when reading the pressure plate. Therefore, it is possible to provide an easy-to-use image reading apparatus and an image forming apparatus including the image reading apparatus.

1: Contact glass 2: Pressure plate 3, 4: Reflecting plate 5: Exposure lamp 6: Document thickness sensor 11: CCD 12: IPU 13: Image storage device 14: Reading control unit 15: RAM 16: Non-volatile memory 17: CPU
18: Bus 19: Motor 20: Operation unit

Japanese Patent Laid-Open No. 04-334163

Claims (8)

An image reading apparatus having an image reading unit that reads an image by scanning a document set on the upper surface of the contact glass from the lower side of the contact glass, and a reading condition setting unit that sets a reading condition by the image reading unit There,
Document thickness detection means for detecting the thickness of the entire document by scanning the document set on the upper surface of the contact glass from the lower surface side of the contact glass;
Area discriminating means for discriminating an area having a thickness different from the thickness of the original on the entire surface of the original based on thickness information indicating the thickness distribution of the entire original detected by the original thickness detecting means. And
The image reading apparatus, wherein the reading condition setting unit includes a unit that sets the reading condition for each region including the regions having different thicknesses determined by the region determining unit.   2. The image according to claim 1, wherein the reading condition setting unit sets only the thickest region as a reading region when there is a region having the different thickness as a result of the determination by the region determining unit. Reader. The image reading apparatus according to claim 1,
Providing a threshold value storage means for storing and holding a threshold value for specifying the regions of different thicknesses;
The reading condition setting unit sets, as a reading region, only a region having a thickness exceeding the threshold when there is a region having a different thickness as a result of the determination by the region determining unit. Reader. The image reading apparatus according to claim 1,
Providing a threshold value storage means for storing and holding a threshold value for specifying the regions of different thicknesses;
The reading condition setting means adds the threshold value to the thickness of the area having the smallest thickness when the areas having different thicknesses as a result of the discrimination by the area discriminating means, and exceeds the value after the addition. An image reading apparatus characterized in that only a region having a predetermined thickness is set as a reading region. The image reading apparatus according to claim 1,
A threshold value storage means for storing and holding a threshold value for specifying the regions having different thicknesses and a limit value for representing the thickness range of the reading region;
The reading condition setting means sets, as a reading area, a thickness area in which a difference with respect to the threshold value is within the limit value when there is an area having the different thickness as a result of the determination by the area determining means. An image reading apparatus. The image reading apparatus according to claim 1,
A threshold value storage means for storing and holding a threshold value for specifying the regions having different thicknesses and a limit value for representing the thickness range of the reading region;
The reading condition setting means adds the threshold value to the thickness of the area having the smallest thickness when there is an area having the different thickness as a result of the discrimination by the area discriminating means. An image reading apparatus characterized in that an area having a thickness within which the difference is within the limit value is set as a reading area. The image reading apparatus according to any one of claims 1 to 6,
A reading mode in which a normal reading mode for reading an image of the entire surface of the original or a specific information reading mode for reading an image of an area having a different thickness is set by an instruction from the outside as a reading mode by the image reading unit Setting means,
When the normal reading mode is set by the reading mode setting unit, the reading condition setting unit sets the reading condition for the entire surface of the original, and the reading mode setting unit reads the specific information. When the mode is set, the reading condition is set for each of the areas including the different thickness areas determined by the area determining means.   An image forming apparatus comprising: the image reading apparatus according to claim 1, wherein image forming processing is performed based on image data read by the image reading unit of the image reading apparatus. .

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