JP2000184128A - Picture reader, control method therefor and recording medium therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To generate an accurate correction by excluding the influence of light of a light source irradiating a document to read a white reference plate with respect to a picture reader which is provided with the white reference plate adjacently to a picture read area of read in the main scanning direction and reads the white reference plate at the time of reading the document and performs correction of the change of the quantity of light. SOLUTION: A light shielding plate 3 is set on the boundary between a picture read area 21 in the main scanning direction and a white reference plate 4 to exclude the influence of light of the light source irradiating a document 1, and the white reference plate 4 is read. The light shielding plate 3 is inclined in accordance with the angle of reading light, which is made incident on a condenser lens, to keep the influence of the light shielding plate 3 minimum. Further, set positions of the white reference plate 4 and the light plate 3 are approximated toward the document in accordance with the size of the document 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image reading apparatus in which a white reference plate is provided adjacent to an image reading area to be read in the main scanning direction, by eliminating the influence of reading light obtained from a document by an image reading section. An image reading device comprising a mechanism for grasping the amount of light for reading the white reference plate and for always positioning the white reference near the document,
A control method of an image reading apparatus for efficiently reading an image by covering the original and the white reference in a minimum reading area, and a computer-readable recording medium equipped with a control procedure in the image reading apparatus It is about.

[0002]

2. Description of the Related Art Here, the definitions of the following terms according to the present invention will be described to clarify the concept included therein.

[0003] The main scanning direction refers to a reading scanning direction in the main direction. Therefore, image data obtained by one main scan is linear one-dimensional image data, and forms one scanning line. For example, in the case of an image reading apparatus using a linear light source lamp, it can be said that one main scan is performed by one irradiation by the linear light source lamp. Also, it usually coincides with the width direction of the original to be read.

[0004] The sub-scanning direction is a scanning direction perpendicular to the main scanning direction, and linear one-dimensional image data obtained by scanning in the main scanning direction is obtained in the sub-scanning direction. The two-dimensional planar image data is accumulated by scanning. Also, it usually coincides with the length direction of the original to be read.

In an image reading apparatus that generates image data of a document to be read and transfers the image data to a host device, a white reference plate is provided adjacent to an image reading area to be read in the main scanning direction, so that one time operation is performed. It is a known technique to read the white reference plate together with the reading in the main scanning direction, read the change in the amount of light, and correct the image data obtained by reading the document.

In the case where a mechanism in which a white reference plate is arranged in the vicinity of a document reading area is employed, when reading the white reference plate, for example, if the end of the document to be read is black, In this case, there is a risk that the amount of light read from the white reference plate is affected by the black portion of the original document, and that the above-described correction operation causes a problem that the image data is disturbed.

Referring to FIG. 7, an image reading apparatus in which a white reference plate is installed adjacent to an image reading area according to the prior art will be described. That is, a white reference plate 54 is disposed on the glass plate 52 on which the document 1 is placed, and a buffer region 61a is provided between the image reading region 61 set in the main scanning direction and the white reference plate 54, so that the document surface Block the effects of

In order to provide the buffer area 61a, it is necessary to set the effective reading area of the image reading apparatus to be large, and it is unavoidable to enlarge the apparatus.

The area read by the image reading apparatus is always constant. For example, even when a document having a width smaller than the image reading area 61 is read, the image data to be transferred to the host apparatus is the same as the image data including the margin. The host device that has received the image data performs processing such as deleting unnecessary blank portions.

Referring to FIGS. 8 and 9, a flow of image reading by an image reading apparatus in which a white reference plate is installed adjacent to an image reading area according to a conventional technique will be described.

As shown in the block diagram showing the configuration of the image reading apparatus in FIG. 8, a processing program B54 controls an arithmetic control unit B50 built in the image reading apparatus B05.
The read output of reading the white reference plate is separated from the read output of the reading unit B55 to separate the adjustment unit B51.
, A correction value is calculated, and when the image processing unit B53 generates image data, correction is performed with the correction value.

The flow of image reading will be described with reference to the flowchart of FIG.

In step S51, the image reading device B0
Reference numeral 5 turns on the light source lamp, proceeds to step S52, starts reading in the main scanning direction, reads a document, and reads a white reference plate on the same reading scanning line.

In step S53, the adjustment unit B51 generates a correction value based on the light amount value obtained by reading the white reference plate, and generates image data based on the read output of the read scanning line in the image processing unit B53. .

If the subsequent reading output is to be performed in step S56, the process returns to step S52 to perform reading on the subsequent reading scanning line.

If reading in the sub-scanning direction has been completed in step S56, the flow advances to step S57 to transfer image data to the host device B02, and the flow ends.

[0017]

As described above, the image reading apparatus provided with the white reference plate adjacent to the image reading area read in the main scanning direction realized by the conventional technique has the following problems. is there.

When the white reference plate is arranged close to the original, for example, when the edge of the original is black, the read output value obtained by reading the white reference plate is affected by the color of the original. There is a risk that the output will deviate and the correction value will be disturbed.

In order to prevent the above-mentioned obstacle, a buffer area is provided between the area for reading the original and the white reference plate.
By this measure, the read output value obtained by reading the white reference plate is not disturbed, but the buffer area inevitably increases the size of the apparatus.

[0020]

In order to solve the above problems, the present invention employs the following means.

1) In an image reading apparatus in which a white reference plate is provided adjacent to an image reading region to be read in the main scanning direction, a light-shielding plate is provided between the region for reading a document to be read and the white reference plate. Provide.

By adopting this means, an effect is obtained that the output obtained by reading the white reference plate is shielded from the influence of the light source illuminating the original.

2) The position where the white reference plate and the light-shielding plate are arranged is moved in conjunction with a document setting unit for setting the mounting position according to the width of the document to be read.

By taking this means, the image reading apparatus has an effect of positioning the white reference plate and the light shielding plate near the document.

3) The image reading device detects the position of the document setting section when reading an image and sets the range of image data generation.

By taking this means, the image reading apparatus has an effect of providing the host device with image data excluding the image of the blank portion where the document does not exist.

4) A procedure for detecting the position of the original setting section and a procedure for setting an image reading area from the position of the original setting section when reading an image are stored in a computer-readable recording medium.

By taking this means, the image reading apparatus has an effect of providing a procedure for providing the host device with image data excluding an image in a blank portion where no document exists.

[0029]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention takes the following forms.

1) In an image reading apparatus in which a white reference plate is provided adjacent to an image reading area to be read in the main scanning direction, an image reading area for reading a document to be read and a white color adjacent to the image reading area A light-shielding plate is provided at the boundary with the reference plate.

By taking this form, the white reference plate has the effect of reading the output value without being affected by the light source light radiating the adjacent original.

2) The light-shielding plate is attached at an inclination angle equal to the angle at which the irradiation light reflected by the white reference plate is incident on the condenser lens.

By taking this form, the light-shielding plate has an effect of keeping the shadow that blocks the light emitted from the white reference plate and the original to a minimum.

3) The white reference plate is provided closer to the light source lamp than the original to be read.

By taking this form, the white reference plate has the effect of increasing the amount of light emitted by the light source lamp.

4) The white reference plate and the light-shielding plate are moved in conjunction with a document setting section for setting a position on which a document to be read is placed.

By taking this form, there is obtained an effect that the above-mentioned white reference plate is always positioned near the original to be read.

5) The white reference plate and the light-shielding plate, which move in conjunction with the document setting unit for setting the position on which the document to be read is set, are provided with the white reference plate and the light source lamp depending on their positions. To change the distance.

By taking this form, the white reference plate has an effect of selecting an irradiation distance according to the light emitting position of the light source lamp.

6) The inclination of the light-shielding plate, which moves in conjunction with the original setting unit for adjusting the position of the original to be read, is changed according to the position.

By taking this form, the light-shielding plate has an effect of always keeping the shadow that blocks the light emitted to the white reference plate and the original to a minimum.

7) In a control method for an image reading apparatus in which a white reference plate is provided adjacent to an image reading area to be read in the main scanning direction, a document setting unit for setting a position where a document to be read is placed. The reading length in the main scanning direction is detected based on the position where is set, and the read image data corresponding to the size of the document is generated and transferred to the host device.

By adopting this mode, the image reading apparatus has an effect of always providing the host device with image data from which blank portions other than the original have been deleted.

8) A procedure for detecting a reading length in the main scanning direction by a position for setting a document setting unit for setting a position where a document to be read is placed, and a procedure for detecting the reading length in the main scanning direction. And generating a read image data and transferring the read image data to the host device. The control program is stored in a computer-readable recording medium.

By taking this form, the image reading apparatus corrects the image data obtained by reading the original in accordance with the read value of the white reference plate, and deletes a blank portion from the image data to obtain the host apparatus. And a procedure for transferring the information to the server.

[0046]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A representative embodiment according to the present invention will be described with reference to FIGS. That is, FIGS. 1 to 4 are explanatory views of the principle for explaining the mechanism based on a representative embodiment according to the present invention, and FIG. 5 is a block diagram showing a configuration based on a representative embodiment of a control method according to the present invention. FIG. 6 is a flowchart based on the block diagram shown in FIG.

Referring to FIG. 1, a light-shielding plate according to one representative embodiment of the present invention will be described. The light-shielding plate 3 is provided on the glass plate 2 on which the original 1 is placed. The effective reading area 20 in the main scanning direction includes an image reading area 21 for actually reading the original 1, the installation width of the white reference plate 4, The buffer area provided in the image reading apparatus according to the conventional technique described above with reference to FIG.

Referring to FIG. 2, a light shielding plate applied to an image reading apparatus using a reduction optical system according to another representative embodiment of the present invention will be described. The light shielding plate 3a is provided with an inclination angle of θ. The inclination angle θ of the light shielding plate 3a is an angle at which the irradiation light reflected by the white reference plate 4 is incident on the condenser lens 5.

In the light incident on the condenser lens 5,
The shadow formed by the light shielding plate 3a having an inclination is only the thickness of the light shielding plate 3a, and the shadow of the light shielding plate 3a is minimized.

The setting of the position of the white reference plate will be described with reference to FIG. 3 according to another representative embodiment of the present invention.

A light source lamp having a straight pipe used as a light source for irradiating a document or the like in the image reading apparatus usually has a reduced light quantity at both ends. Therefore, when the white reference plate is illuminated by the end of the straight tube light source lamp, the correction value may be incorrect because the light is illuminated with a light amount smaller than the light amount illuminating the original.

As shown in FIG. 3, the original 1 is
In setting the distance da from the light source lamp 7 to the white reference plate 4 with respect to the distance db, the white reference plate 4 is moved closer to the light source lamp 7 in order to compensate for the insufficient light amount calculated in advance. I do. By this measure, the amount of light illuminating the white reference plate 4 can be set to be equal to the amount of light illuminating the original 1, and the setting accuracy of the correction value to be corrected according to the change in the amount of light of the entire light source lamp can be increased. it can.

Referring to FIG. 4, according to another representative embodiment of the present invention, the position of the white reference plate and the position of the light shielding plate which move in conjunction with the setting of the end position of the original to be read are set. explain.

The document setting unit 8 can also be used as a document guide of a document supply unit, for example, if the image reading device is a device of a type that transports the document 1a or 1b with an optical system fixed. Further, for example, if the image reading apparatus is a flat bed type apparatus that reads an image by moving the optical system while fixing the original, the image reading apparatus can be provided on the glass plate 2 on which the original 1a or 1b is placed.

The original setting section 8 is connected to the white reference plate 4a by a connecting section 9. The white reference plate 4a is movably locked in the main scanning direction along the reference plate guide 10, and the reference plate guide 10 is fixed to the glass plate 2 at an appropriate inclination angle in the main scanning direction. Therefore, the distance from the glass plate 2 is changed by moving the white reference plate 4a in the main scanning direction. This is because the distance between the light source lamp 7 set in parallel with the glass plate 2 and the white reference plate 4a is changed by moving the white reference plate 4a in the main scanning direction. Suggest that.

The white reference plate 4a includes a light-shielding plate 3b which is rotatably locked by an appropriate hinge mechanism. Further, when the white reference plate 4a moves along the reference plate guide 10, the tip of the light-shield plate 3b is fixed to the light-shield plate guide 11 which is fixed at a different inclination angle from the reference plate guide 10. Move along.

This suggests that a series of operations described below are performed in conjunction with the position setting of the document setting unit 8.

That is, if the position of the original setting unit 8 is moved in the main scanning direction in accordance with the end of the original 1a or 1b to set the position, the white reference plate connected to the original setting unit 8 can be obtained. 4a moves in the main scanning direction to set the position, and at the same time, the distance between the white reference plate 4a and the light source lamp 7 is changed and newly set. Further, the inclination angle of the light shielding plate 3b locked to the white reference plate 4a is changed and newly set.

FIG. 4A shows a state where a document 1a having a wide width in the main scanning direction is placed. The document setting unit 8 movably locked in the main scanning direction sets a position in the main scanning direction according to an end of the document 1a.

The position of the white reference plate 4a in the main scanning direction is set in accordance with the set position of the original setting unit 8, and at the same time, the distance between the white reference plate 4a and the light source lamp 7 is set as the distance da1. The white reference plate 4a is a light source lamp 7
It is fixed at a position close to. In addition, the above-mentioned white reference plate 4
The inclination angle formed by the light shielding plate 3b provided in a is also fixed as the angle θ1 in accordance with the angle of incidence on the condenser lens.

FIG. 4B shows a state in which a document 1b having a narrow width in the main scanning direction is placed. The document setting unit 8 movably locked in the main scanning direction sets a position in the main scanning direction according to an end of the document 1b.

The position of the white reference plate 4a in the main scanning direction is set in accordance with the set position of the document setting unit 8, and at the same time, the distance between the white reference plate 4a and the light source lamp 7 is set as the distance da2. The white reference plate 4a is a light source lamp 7
Fixed at a more distant position. In addition, the above-mentioned white reference plate 4
The angle of inclination formed by the light shielding plate 3b provided in a is also fixed as the angle θ2 in accordance with the angle of incidence on the condenser lens.

Further, by adding a mechanism for detecting the set position of the document setting unit 8 by an appropriate method, the image reading apparatus recognizes the end of the document 1a or 1b in the main scanning direction in advance, At the same time, since the position of the white reference plate 4a is recognized in advance, it is possible to efficiently calculate a correction value to be generated based on the output value obtained by reading the white reference plate 4a, and at the same time, from the read output, the original 1a or 1b and Parts other than the white reference plate 4a can be deleted.

Referring to FIGS. 5 and 6, according to another representative embodiment of the present invention, the positions of the white reference plate and the light shielding plate which move in conjunction with the setting of the end position of the original to be read. Is described below to generate image data.

FIG. 5 is a block diagram showing the configuration of the image reading device. The details of the mechanism shown in FIG. 5 are shown in FIG.

The operation control section B10 built in the image reading apparatus B01 has an area setting section B12, and the position detection section B1.
An image area to be extracted is set from the image output read by the reading unit B15 based on the position data of the document setting unit detected by the reference unit 6.

The adjustment unit B11 calculates a correction value based on the image output of the white reference plate read by the reading unit B15,
The above-described correction value is applied to the host device B0 based on the read output obtained by reading the document by the reading unit B15.
2 is generated.

The procedure executed by the arithmetic and control unit B10 is controlled by a processing program B14.

FIG. 6 shows a flowchart. The reference numerals used in the respective steps are based on FIG.

In step S01, the light source lamp is turned on.

In step S02, the original setting unit is moved in the main scanning direction, and its position is set in accordance with the end of the original to be read.

In step S03, the area setting section B12 sets a read output area to be extracted based on the position data obtained by detecting the position of the original setting section by the position detecting section B16.

In step S04, the reading unit B15 reads the original and the white reference plate. In step S05, the adjustment unit B11 calculates a correction value based on the read output obtained by reading the white reference plate. Step S06
To correct the read output of the portion where the document was read. At this time, the read output value of the portion other than the read area set in step S03 is deleted as a surplus portion.

In step S07, image data corresponding to the read scanning line is generated based on the corrected read output.

If it is determined in step S08 that the reading area of the document to be read remains and the scanning line is to be set continuously, the process returns to step S04 and the reading is repeated.

If the end of the document has been reached in step S08 and the reading area of the document to be read no longer remains, the flow advances to step S09 to transfer the image data to the host device, and terminate the reading operation.

[0077]

According to the present invention, the following effects can be expected.

1) In an image reading apparatus in which a white reference plate is provided adjacent to an image reading area to be read in the main scanning direction, an image reading area for reading a document to be read and a white color adjacent to the image reading area A light-shielding plate is provided at the boundary with the reference plate.

By taking this means, the white reference plate has the effect of reading the output value without being affected by the light of the light source irradiating the adjacent document and preparing the base for generating an appropriate correction value.

2) The light shielding plate is attached at an inclination angle equal to the angle at which the irradiation light reflected by the white reference plate is incident on the condenser lens.

By taking this measure, the above-mentioned light-shielding plate has an effect that the white light reference plate and the shadow that blocks the irradiation light illuminating the original document are kept to a minimum, and a base for generating an appropriate correction value is obtained.

3) The white reference plate is provided closer to the light source lamp than the original to be read.

By taking this measure, the above-mentioned white reference plate can increase the amount of light emitted from the light source lamp, and can be applied particularly to the irradiation of the white reference plate with the end of the light source lamp where the amount of light tends to be insufficient. As a result, the respective parts of the light source lamp can be effectively used.

4) The white reference plate and the light-shielding plate are moved in conjunction with a document setting section for setting a position on which a document to be read is placed.

By taking this measure, the white reference plate is always positioned near the original to be read, the irradiation conditions of the original and the white reference plate are set to be the same, and the read output value of the image is adjusted. The effect is obtained that the remainder can be deleted.

5) The white reference plate and the light shielding plate, which move in conjunction with the document setting unit for setting the position where the document to be read is placed, are different from the white reference plate and the light source lamp depending on their positions. To change the distance.

By taking this means, the white reference plate has an effect of selecting an irradiation distance in accordance with the light emitting position of the light source lamp.

6) The inclination of the light-shielding plate, which moves in conjunction with the original setting unit for adjusting the position of the original to be read, is changed according to the position.

By taking this measure, the light-shielding plate always keeps the shadow which blocks the light emitted from the white reference plate and the original at a minimum and always keeps the effective reading area of the white reference plate at the maximum. Get the effect.

7) In a control method for an image reading apparatus in which a white reference plate is provided adjacent to an image reading area to be read in the main scanning direction, a document setting section for setting a position on which a document to be read is placed. , The reading length in the main scanning direction is detected based on the position where is set, and the read image data corresponding to the size of the document is generated and transferred to the host device.

By adopting this means, the image reading apparatus always provides the host device with the image data in which the margins other than the original are deleted, so that the data transfer time can be set to the minimum.

8) A procedure for detecting a reading length in the main scanning direction by a position for setting a document setting section for setting a position where a document to be read is placed, and a method for detecting the reading length in the main scanning direction. And a control program for executing the procedure of generating the read image data and transferring the read image data to the host device, in a computer-readable recording medium.

By taking this means, the image reading apparatus corrects the image data obtained by reading the original in accordance with the read value of the white reference plate, and deletes a blank portion from the image data to obtain the host apparatus. And a procedure for transferring the information to the server.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating the principle according to a representative embodiment of the present invention.

FIG. 2 is a diagram illustrating the principle according to a representative embodiment of the present invention.

FIG. 3 is a diagram illustrating the principle according to a representative embodiment of the present invention.

FIG. 4 is a diagram illustrating the principle according to a representative embodiment of the present invention.

FIG. 5 is a block diagram according to a representative embodiment of the present invention.

FIG. 6 is a flowchart according to a representative embodiment of the present invention.

FIG. 7 is a diagram for explaining the principle based on a conventional technique.

FIG. 8 is a block diagram based on a conventional technique.

FIG. 9 is a flowchart based on a conventional technique.

[Explanation of symbols]

 1, 1a, 1b: original 2: glass plate 3: light shielding plate 4: white reference plate 5: condensing lens 6: light receiving element 7: light source lamp 8: original regulating portion 9: connecting portion 10: reference plate guide 11: light shielding Plate guide 20: Effective reading area 21: Image reading area

Claims (8)

[Claims] An image reading apparatus in which a white reference plate is installed adjacent to an image reading area to be read in a main scanning direction, wherein an image reading area (21) for reading a document (1) to be read and the image reading area An image reading apparatus, comprising: a light shielding plate (3) provided at a boundary with a white reference plate (4) adjacent to a reading area (21). 2. A light shielding plate (3a) having an inclination angle (θ) equal to an angle at which irradiation light reflected by the white reference plate (4) is incident on a condenser lens (5). The image reading device according to claim 1, further comprising: 3. The image reading apparatus according to claim 2, wherein the white reference plate is provided closer to the light source lamp than the original to be read. Item 2. The image reading device according to Item 1. 4. A white reference plate (4a) and a light shielding plate which move in conjunction with a document setting unit (8) for setting a position on which a document (1) to be read is placed. The image reading device according to claim 1, wherein (3b) is provided. 5. A white reference plate (4a), which moves in conjunction with a document setting unit (8) for setting a position on which a document (1) to be read is placed, in the image reading apparatus. The image reading device according to claim 4, wherein the light shielding plate (3b) has means for changing a distance between the white reference plate (4a) and the light source lamp (7) depending on a position thereof. 6. A white reference plate (4a), which moves in conjunction with a document setting unit (8) for setting a position on which a document (1) to be read is placed, in the image reading apparatus. The image reading device according to claim 4, wherein the light shielding plate (3b) has means for changing an inclination of the light shielding plate (3b) depending on a position thereof. 7. A control method for an image reading apparatus in which a white reference plate is provided adjacent to an image reading area to be read in a main scanning direction, wherein a position at which the original (1) to be read is placed is regulated. A reading length in the main scanning direction is detected based on a position at which the document setting unit (8) is set, and read image data corresponding to the size of the document (1) is generated and transferred to a host device. A method for controlling an image reading device. 8. A recording medium for storing a control program for an image reading apparatus in which a white reference plate is provided adjacent to an image reading area to be read in the main scanning direction, the position where an original to be read is set. A control program for executing a procedure of detecting a reading length in the main scanning direction according to a position at which a document setting unit is set, and a procedure of generating read image data corresponding to the size of the document and transferring the data to a host device. A computer readable recording medium, characterized by storing