JP2001053934A - Image reader - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform shading correction without feeling trouble in both reference level corrections of black and white. SOLUTION: In this image reader, a casing 1 is made circular and the reading part of the casing 1 is provided with a lid 12. On the inner surface of the lid 12, a white reference plate 14 and a back reference plate 15 are attached on the surface to which a fiber array plate(FAP) 4 and a document D contacted. The lid 12 can be rotated in the arrow direction along the casing 1, a power source switch is linked and the emission of irradiating light from a light source 5 is controlled by opening/closing the lid 12. Therefore, each time a power source is turned on, correcting processing can be executed. When the lid 12 is opened, reference values are respectively lead in the order of black reference plate 15 and white reference plate 14 and in a state of exposing a roller 6 and the FAP 4, the document D can be read.

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, and more particularly to an image reading apparatus having a pen-like housing.

[0002]

2. Description of the Related Art Conventionally, in an image reading apparatus such as an image scanner, white correction and black correction of an input signal are indispensable. The signal read by the image sensor fluctuates due to a temporal change or a temperature change of the image sensor itself or a light source that irradiates the document to be read. Therefore, when there is a large change, it is necessary to correct the black level and the white level before the reading operation starts.

As the simplest method, there is known a method of preparing a white reference plate or a black reference plate, reading these reference plates, and performing shading correction of an input signal using the read values as reference values. I have. However, according to this method, not only is it necessary to prepare a white reference plate and a black reference plate, but the user is also forced to perform an operation of correcting them, so that the user has an extra need. There is a problem that the addition of the process requires a very troublesome operation, which may impair the merchantability.

As a conventional example for solving such a problem, a lid of an image scanner or the like or a case corresponding to the lid is provided, and a white surface or a white reference plate is provided on the inner surface of the lid or the case. There is known a device that irradiates predetermined light to perform shading correction using a value obtained by reading the reflected light as a reference signal.

[0005] For example, FIG.
FIG. 1 is a cross-sectional view illustrating a schematic configuration of a “hand scanner” disclosed in Japanese Patent Application Laid-Open No. 5-085154.

[0007] In FIG. 7, the hand scanner of the conventional example 1 has a housing 110 provided with a protective cover 130 for protecting the image reading sensor unit 120. When the photoelectric conversion element 123 of the image reading sensor unit 120 is operated in this state, the photoelectric conversion element 123
The value obtained by reading the reflected light from the white surface 140 disposed inside the protective cover 130 and irradiated by the rod lens array 122 with the rod lens array 122 is used as a white reference signal. At this time, the image processing unit 150 stores the white reference signal and performs shading correction on the image signal obtained by the photoelectric conversion element 123 at the time of reading the document based on the stored white reference signal.

FIG. 8 shows a conventional example 2 as disclosed in
BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a cross-sectional view illustrating a schematic configuration of a “shading correction method for a hand-held optical reader” disclosed in Japanese Patent Application Laid-Open No. 05-2689.

The image reading apparatus of the second prior art shown in FIG. 8 includes a reading unit body 210, a case 220, a blank sheet 230 for shading correction, and an image sensor 24.
0 and a signal processing circuit 250.

A white sheet 230 for shading correction is provided inside the case 220, specifically at the bottom of the case 220, and a white surface serving as a white reference value for shading correction is automatically set every time the reading unit body 210 is mounted. It is a configuration that can be read.

[0010]

However, in an image reading apparatus, white level correction and black level correction are important problems. In order to cope with a change in the characteristics of the image sensor, the signal level must be corrected each time a change occurs. Normally, white and black papers and boards that serve as white and black standards are prepared,
By reading this, a reference value for correction is obtained.
However, this operation is not only troublesome for the user, but also causes a problem that correction cannot be performed if the reference plate is lost. On the other hand, only the countermeasures shown in the conventional example cause problems as described later.

A first problem is that, in the above-described conventional example, the reading surface is fixed by mounting a white reference plate in a lid or a case. In the configuration in which only the reference plate is provided, only one fixed surface can be read, so that only one of the reference values can be obtained. Therefore,
Although some image sensor elements require correction using the other reference value (for black level correction in the conventional example), shading correction is performed because only one of the reference plates is provided. There is a problem that can not be performed.

As a second problem, in each of the conventional examples, the case and the lid are detached and used, so that it is troublesome for the user to remove and use these for bothersome correction. However, since a member serving as a white reference is provided inside the lid or the case, there is a problem that if the lid and the case are lost, the correction process cannot be performed.

As a third problem, in the above conventional example, when a reading operation by an image sensor is performed,
After the lid or the case is removed and used, the correction is automatically started at the same time when the lid or the case is mounted again, so that the correction is performed for the next use after the use. Therefore, there is a problem that the reference value cannot be read immediately before use, although it is preferable that the correction be made immediately before use in order to eliminate the influence of the temperature change and the change over time.

The above-mentioned problems can be summarized as follows: "a detachable lid or case is used";"there is only one fixing method"; It is caused by three reasons.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and it is an object of the present invention to provide an image reading apparatus capable of performing shading correction without causing a user to feel troublesome in performing both black and white reference level corrections. It is intended to provide a device.

[0016]

According to a first aspect of the present invention, there is provided an image reading apparatus comprising a housing having a predetermined shape, wherein the reference is a reference for shading correction inside the housing. A plate is provided.

According to a second aspect of the present invention, in the first aspect, the reference plate is one or both of a white reference plate serving as a white reference and a black reference plate serving as a black reference. Features.

The third aspect of the present invention is the first or second aspect.
In the invention described, the housing has an image sensor element provided with a window in the photosensitive element section, a fiber array plate adhered to the photosensitive element section, a light source, a roller, an encoder, and a circuit board. The reference plate is arranged so as to be in contact with the fiber array plate.

According to a fourth aspect of the present invention, in the third aspect of the present invention, the image reading device is provided with a lid which protects the roller and the contact surface of the fiber array plate with the object to be read when not in use. A reference plate is provided on the inner surface of the lid, and the reference plate comes into contact with the fiber array plate by moving the lid along the housing.

According to a fifth aspect of the present invention, in the fourth aspect of the present invention, an elastic body (spring) is provided between the lid and the reference plate, and when the lid is opened and closed, the reference plate is connected to the fiber array plate. When the contact is made, the reference plate is pressed against the fiber array plate by an elastic body (spring).

The invention according to claim 6 is the invention according to claim 4 or 5.
In the invention described in the above, the power of the power
A power switch for switching N / OFF is provided.

According to a seventh aspect of the present invention, in the third aspect of the present invention, the image reading device is provided with a case so as to protect the contact surface of the fiber array plate with the object to be read and the roller when not in use. A reference plate is provided on the inner surface of the case, and the reference plate comes into contact with the fiber array plate by moving the case along the housing.

According to an eighth aspect of the present invention, in the seventh aspect, an elastic body (spring) is provided between the case and the housing, and the image forming apparatus reads an object to be read by opening and closing the case. It is characterized in that the case is configured to be lifted by an elastic body (spring) when possible.

The invention according to claim 9 is the invention according to claim 7 or 8.
In the invention described in the above, a power switch is provided for switching the power on / off in accordance with the opening / closing operation of the case.

According to a tenth aspect of the present invention, in the third aspect of the present invention, in the image reading apparatus, a reference plate is provided on an inner surface of the housing, and a reading stage comprising a light source, an image sensor element, and a fiber array plate is used as a reference. It is characterized by being rotatable so as to be in contact with the plate.

According to the eleventh aspect, in the tenth aspect, the power supply is turned on in response to the movement of the reading stage.
A power switch for switching between ON and OFF is provided.

According to a twelfth aspect of the present invention, there is provided the third aspect of the present invention.
The invention according to any one of the first to eighth aspects, characterized in that the reference plate is configured to maintain a state in which the reference plate is in close contact with the fiber array plate for about several milliseconds.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of an image reading apparatus according to the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 to FIG. 6 show an embodiment of an image reading apparatus according to the present invention.

FIG. 1 is a perspective view showing a schematic configuration of an image reading apparatus according to an embodiment of the present invention. 1, an image reading apparatus according to an embodiment of the present invention includes a housing 1, a circuit board 2, an image sensor element 3, an FAP (fiber array plate) 4,
The housing 1 includes a light source 5, a roller 6, and an encoder 7.
And an external device.

As long as the housing 1 is formed in a pen shape, the built-in image sensor element 3, FAP4, light source 5, and roller 6 are arranged irrespective of a circle, a polygon, or any combination. Various aspects can be realized by changing the position of the image.

The circuit board 2 controls the driving of the image sensor element 3, amplifies the reflected light from the object read by the image sensor element 3 with an operational amplifier or the like, and converts the amplified signal into a digital signal. It is configured by a circuit that performs such processing as

The image sensor element 3 is a one-dimensional image sensor element comprising a drive circuit formed on a glass substrate and a photosensitive element array provided with a window.

In the present embodiment, the image sensor element 3 relates to a one-dimensional image sensor element. For example, a two-dimensional image sensor in which a plurality of rows of image sensor arrays are integrated in the image sensor element Etc. can be equally applied.

More specifically, in the case of a color image sensor, the light source is white and the image sensor array is R
In the case of reading colors in three colors (red), B (blue), and G (green), it is also possible to use an image sensor element in which three one-dimensional image sensor arrays are arranged.

The FAP (fiber array plate) 4
A plurality of optical fibers are bundled, and light emitted from a light source 5 passes through a window of a photosensitive element portion of the image sensor element 3, passes through the FAP 4, enters a document, and further reflects light from the document. Again passes through the FAP 4 and enters the photosensitive element portion of the image sensor element 3.

The light source 5 is usually constituted by a light-emitting element such as an LED, and is provided with a power switch O provided so as to interlock with opening and closing operations of a cover and a case provided on the housing 1.
In response to the N / OFF switching, emission control of light for irradiating the original is performed.

The roller 6 is provided for stabilizing the running performance of the image reading device when scanning a document.

The encoder 7 detects the current scanning position of the document from the rotation speed of the roller 6 described above.

The cable 8 is used when the signal read by the image sensor element 3 is amplified and digitized by the circuit board 2 and the processed signal is transmitted to an external device. .

FIG. 2 is a sectional view of the image reading apparatus according to the embodiment of the present invention shown in FIG. 1 taken along a line AB. In the cross section between A and B of the image reading device, an image sensor element 3 and
The FAP 4, the light source 5, and the roller 6 are arranged at the positions shown.

The light emitted from the light source 5 passes through the window of the photosensitive element portion of the image sensor element 3, passes through the FAP 4, and irradiates the original, and the reflected light from the original passes through the FAP 4 again and returns to the image sensor. The light enters the photosensitive element portion of the element 3.

The advantage of the above configuration is that the physical distance between the image sensor element 3 and the light source 5 can be made very small, and the light source 5 is arranged directly above the image sensor element 3. The point that can be. By applying such a configuration to a reading device such as a scanner, the size of the apparatus can be reduced.

FIG. 3 shows the FAP according to the embodiment of the present invention.
FIG. 8 is a diagram showing details of (fiber array plate),
FIG. 2 is a perspective view showing a part of a one-dimensional sensor array having a resolution of book / mm.

In FIG. 3, a glass substrate 30 has a fiber 3 covered with a light absorbing layer 32 through a transparent adhesive layer 31.
3 are adhered to a FAP (fiber array plate) 4 in which an array 3 is bundled.

Each of the opaque common electrode 36, the photosensitive layer 37, and the transparent individual electrode 38 has a hole for guiding light (illumination light 35) emitted from a light source (not shown) and transmitted through the LED array 31. A light hole 39 is formed.

The light transmitted through the LED array 31 passes through the light guide hole 39 as illumination light 35, and enters the document D through the fiber 33 whose side surface is covered with the light absorbing layer 32.
The reflected light from the document D returns through the fiber 33 again as the signal light 40 and reaches the photosensitive element portion of the image sensor element 3.

As described above, since the side surface of the fiber 33 is covered with the light absorbing layer 32, one fiber 33
Irrespective of whether the incident light is the illumination light 35 or the signal light 40, there is no other leakage. Therefore, even when the FAP (fiber array plate) 4 is used, it is possible to prevent the resolution from deteriorating.

FIG. 4 is a sectional view showing a first embodiment of the image reading apparatus according to the embodiment of the present invention. When not used in FIG. 4A, the casing 1 is formed of a circular shape.
The cover 12 is provided in a portion corresponding to the reading portion of the original. A white reference plate 14 and a black reference plate 15, which characterize the present invention, are attached to the inner surface of the lid 12 on the surface where the FAP 4 and the document D are in contact.

The lid 12 is configured to be rotatable along the housing 1 in the direction of the arrow. A power switch (not shown) is interlocked with the lid 12. When the lid 12 starts to be opened at the time of use, the power switch is turned on, the emission of light from the light source 5 is started, and the power is turned on by closing the lid 12. The switch is turned off, and the emission of irradiation light from the light source 5 is stopped. By performing such control, a correction process can be performed each time the power is turned on.

As shown in FIG. 4B, when the lid 12 is rotated in the direction of the arrow, first, the black reference plate 15
The black reference signal is obtained by reading the black reference plate 15 once at a position where the black reference signal is brought into close contact. The operation of temporarily stopping at the position where the lid 12 is in close contact with the FAP 4 is sufficient if the rotation mechanism of the lid 12 is configured to perform an operation such that a shallow latch is engaged. This is because the reading time for one line is on the order of several milliseconds.

As shown in FIG. 4C, the lid 1
2 in the direction of the arrow, the white reference plate 14
The white reference signal is acquired by reading the white reference plate 14 once and stopping at a position where the white reference signal is closely attached to the image. The operation of temporarily stopping at a position in close contact with the FAP 4 is configured to perform an operation such that a shallow latch is applied to the rotation mechanism of the lid 12 as described above. This is because the reading time for one line is on the order of several milliseconds.

A spring 16 is provided on each of the white reference plate 14 and the black reference plate 15, and each reference plate is pressed against an FAP (fiber array plate) 4 when performing a reading operation for correction. It is configured so that it can be closely attached.

As shown in FIG. 4D, the white reference signal and the black reference signal are read, respectively, and the cover 12 is further rotated in the direction of the arrow so that the roller 6 and the FAP (fiber array plate) 4 are exposed. And the document D can be read.

FIG. 5 is a sectional view showing a second embodiment of the image reading apparatus according to the present invention. When not used in FIG. 5A, the housing 1 is formed of a square,
And a case 17 that wraps around the housing 1. A white reference plate 14 and a black reference plate 15, which are features of the present invention, are attached to the inner surface of the case 17 on the surface where the FAP 4 and the document D are in contact.

The case 17 is slidable along the housing 1 in the direction of the arrow. A power switch (not shown) is interlocked with the case 17, and the power switch is turned on by opening the case 17 at the time of use, and emission of light from the light source 5 is started.
When the switch 7 is closed, the power switch is turned off, and the emission of the irradiation light from the light source 5 is stopped. By performing such control, a correction process can be performed each time the power is turned on.

As shown in FIG. 5B, the case 17
Is slid in the direction of the arrow, first, the white reference plate 14 temporarily stops at a position where the white reference plate 14 is in close contact with the FAP 4, and the white reference plate 14 is read to obtain a white reference signal. The operation of temporarily stopping at a position in close contact with the FAP 4 is configured to perform an operation such that a shallow latch is applied to the slide mechanism of the case 17 as in the first embodiment described above.

As shown in FIG. 5C, when the case 17 is further slid, the black reference plate 15 temporarily stops at a position where the black reference plate 15 is in close contact with the FAP 4, and the black reference plate 15 is read to obtain a black reference signal. . The operation of temporarily stopping at a position in close contact with the FAP 4 is the same as that described above.

As shown in FIG. 5D, the white reference signal and the black reference signal are read, and the case 17 slides in the direction of the arrow to expose the roller 6 and the FAP (fiber array plate) 4. The document D is ready to be read.

At this time, the case 17 is lifted up by the spring 16 provided between the case 1 and the case 1 so that the roller 6 and the FAP 4 can come into contact with the document D.

FIG. 6 is a sectional view showing a third embodiment of the image reading apparatus according to the present invention. When not used in FIG. 6A, a white reference plate 14 and a black reference plate 15, which are features of the present invention, are provided on the inner surface of the housing 1, and reading is performed by the light source 5, the image sensor element 3, and the FAP 4. The mechanism itself is configured to be movable inside the housing 1.

A major difference from the first and second embodiments described above is that there is no need to provide a lid or a case.
White reference plate 14 and black reference plate 1 provided inside housing 1
5, the light source 5, the image sensor element 3, and the operation of reading the document D
The correction is performed by a reading mechanism including the FAP4 and the FAP4.

As shown in FIG. 6B, in the reading mechanism including the light source 5, the image sensor element 3, and the FAP 4, first, the white reference plate 14 provided on the inner surface of the housing 1 comes into close contact with the FAP 4. Once stopped at the position, the white reference plate 14 is read to obtain a white reference signal. For the operation of temporarily stopping at the position where the rotation mechanism comes into close contact with the FAP 4, it is sufficient to configure the rotation mechanism to perform an operation such that a shallow latch is engaged.

As shown in FIG. 6C, when the reading mechanism including the light source 5, the image sensor element 3, and the FAP 4 is further rotated, the black reference plate 15 temporarily stops at the position where the black reference plate 15 comes into close contact with the FAP 4, and the black reference plate 15 stops. By reading the reference plate 15, a black reference signal is obtained. The operation of temporarily stopping at a position in close contact with the FAP 4 is the same as that described above.

As shown in FIG. 6D, when the white reference signal and the black reference signal are read, respectively, the reading mechanism including the light source 5, the image sensor element 3, and the FAP 4 rotates to rotate the FAP (fiber array). The original D can be read with the plate 4 exposed.

The above-described embodiment is a preferred embodiment of the present invention, and various modifications can be made without departing from the spirit of the present invention. For example,
In the embodiment of the present invention, the configuration including both the white reference plate and the black reference plate is shown, but when the white reference value is unnecessary, or when the black reference value is unnecessary, any one of them is used. It is also possible to provide a reference plate.

[0066]

As is apparent from the above description, according to the image reading apparatus of the present invention, immediately before starting the reading operation, and furthermore, the user feels troublesome that the correction is being performed. Black-and-white shading correction can be performed without any problem. Therefore, by performing the black and white shading correction immediately before the reading operation, the correction accuracy can be improved, and since there is no need to provide a lid or a case in which a black and white reference plate is provided inside as in the related art, The troublesomeness of the user can be further reduced.

According to the image reading apparatus of the present invention, the signal for correction is read by the white reference plate and the black reference plate during the operation of opening the lid. This means that the correction immediately before use can be performed without the user's awareness.

Further, unlike the conventional detachable type, the lid is attached to the housing, so that there is no danger of loss, and the loss of black and white shading due to loss can be prevented.

[Brief description of the drawings]

FIG. 1 is an external view illustrating a basic configuration of an image reading apparatus according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view when the image reading apparatus of FIG. 1 is cut between AB.

FIG. 3 is a perspective view illustrating a basic configuration of an image sensor element according to the embodiment of the present invention.

FIG. 4 is a sectional view illustrating a schematic configuration of an image reading apparatus according to a first embodiment of the present invention.

FIG. 5 is a sectional view showing a schematic configuration of an image reading apparatus according to a second embodiment of the present invention.

FIG. 6 is a sectional view showing a schematic configuration of an image reading apparatus according to a third embodiment of the present invention.

FIG. 7 is a plan view showing a schematic configuration of Conventional Example 1.

FIG. 8 is a cross-sectional view illustrating a schematic configuration of a second conventional example.

[Explanation of symbols]

 Reference Signs List 1 housing 2 circuit board 3 image sensor element 4 FAP (fiber array plate) 5 light source 6 roller 7 encoder 8 cable

Claims (12)

[Claims] 1. An image reading apparatus comprising a casing having a predetermined shape, wherein a reference plate serving as a reference for shading correction is provided inside the casing. 2. The image reading apparatus according to claim 1, wherein the reference plate is one or both of a white reference plate serving as a white reference and a black reference plate serving as a black reference. 3. The image forming apparatus according to claim 1, wherein the housing includes: an image sensor element having a window provided in the photosensitive element unit; a fiber array plate adhered to the photosensitive element unit; a light source; a roller; an encoder; 3. The image reading device according to claim 1, wherein the reference plate is disposed so as to be in contact with the fiber array plate. 4. 4. The image reading device according to claim 1, further comprising: a cover that protects the contact surface of the fiber array plate with the object to be read and the roller when not in use, wherein the reference plate is provided on an inner surface of the cover. The image reading apparatus according to claim 3, wherein the reference plate is configured to contact the fiber array plate by moving the lid along the housing. 5. An elastic body (spring) is provided between the lid and the reference plate. When the reference plate comes into contact with the fiber array plate by opening and closing the lid, the elastic body (spring) is provided. The image reading apparatus according to claim 4, wherein the reference plate is pressed against the fiber array plate by a spring. 6. A power supply is turned on according to an opening / closing operation of the lid.
6. The image reading apparatus according to claim 4, further comprising a power switch for switching between ON and OFF. 7. The image reading device, wherein a case is provided so as to protect a contact surface of the fiber array plate with an object to be read and the roller when not in use, and the reference plate is provided on an inner surface of the case, The image reading apparatus according to claim 3, wherein the reference plate is configured to contact the fiber array plate by moving the case along the housing. 8. An elastic body (spring) is provided between the case and the housing, and the elastic body (spring) is provided when the image forming apparatus can read an object to be read by opening and closing the case. The image reading device according to claim 4, wherein the case is configured to be lifted by a spring. 9. A power supply according to an open / close operation of the case.
9. The image reading apparatus according to claim 7, further comprising a power switch for switching between N and OFF. 10. The image reading apparatus, wherein the reference plate is provided on an inner surface of the housing, and a reading unit including the light source, the image sensor element, and the fiber array plate is rotated so as to contact the reference plate. The image reading device according to claim 3, wherein the image reading device is configured to be capable of being used. 11. The image reading apparatus according to claim 10, further comprising a power switch for turning on / off a power supply according to movement of the reading stage. 12. The image according to claim 3, wherein the reference plate is configured to maintain a state in which the reference plate is in close contact with the fiber array plate for about several milliseconds. Reader.