JPH10243213A - Image reader - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image reader for book original by which the deceleration of reading speed is prevented, without requiring much time for image- processing by performing image distortion correction and image density correction at the binding part of book original. SOLUTION: This reader has original platens 1 and 1 for placing a book original BO at a prescribed position, holding means for holding the image plane of book original BO, which is spread to both sides, placed at the prescribed position on the original platens 1 and 1 on a reading plane 273 of the almost the same plane, image reading means (lens 106 and CCD 101 or the like) arranged at a prescribed distance with respect to the reading plane 273, book original form recognizing means for recognizing the binding part form of book original BO spread to both the sides in the state of holding the image plane of book original BO, which is spread to both the sides, placed at the prescribed position on the original platens 1 and 1 through the holding means, and image- processing part for correcting the image distortion of binding part BOa from the binding part form of book original BO, recognized by the book original form recognizing means.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an image reading apparatus, and more particularly to an image reading apparatus for reading an image of a book document.

[0002]

2. Description of the Related Art As an image reading apparatus, for example, a technique described in Japanese Patent Application Laid-Open No. 5-161003 has been proposed. This technology includes a document table on which a document is placed, document reading means arranged at a predetermined distance from the document table for reading a document placed on the document table, Boundary detecting means for detecting a boundary between the document and the platen based on the output of the means, and detecting means for detecting the output of the document reading means at a point at a predetermined distance from the boundary in the document based on the boundary detecting means; Correction means for correcting the output of the document reading means based on the output of the detection means.

[0003]

However, in the above technique, the boundary detecting means detects the boundary between the document and the platen and corrects the image information according to the result. There is no restriction, and the surface of the manuscript can be any shape. Then, "almost all of the read image information is corrected", and the image processing takes a long time, resulting in a problem that the reading speed is reduced.

In addition, there is a problem that a large amount of memory is required to handle a large amount of image data, which leads to an increase in cost and an increase in size of a mechanical device.

[0005] Further, even if the original document has a tilt (skew), the inclination is determined by the height (reading surface shape) of the original document.
However, there is a problem that the image is erroneously recognized as the boundary position due to the above, and the correct image cannot be reproduced.

Further, since the image processing is performed after the reading of the original document is completed, there is a problem that it takes extra time.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and an object of the present invention is to provide a method for calculating an image by calculating an error from a specified reading surface position. Provided is an image reading apparatus that specifies a reading range to be processed, corrects image information (image distortion of a binding portion of a book original) based on data calculated by the above error calculation, and enables correct image reproduction. It is in.

An object of the present invention is to specify a reading range to be corrected for light amount by calculating an error from a specified reading surface position, and based on the data calculated by the error calculation. Another object of the present invention is to provide an image reading apparatus that corrects the image density and enables correct image reproduction.

The object of the invention described in claims 6 and 12 is as follows.
It is another object of the present invention to provide an image reading apparatus that performs reading processing of a book document image and image processing in real time to increase the reading speed.

[0010] The object of the invention described in claims 4 and 10 is as follows.
In addition to the above objects, the present invention calculates the amount of skew (skew amount) of a placed original by calculating an error from a specified reading surface position, and removes error data due to the skew. An object of the present invention is to provide an image reading apparatus that specifies a reading range to be processed, corrects image information based on data calculated by a calculation in which error data due to the skew is removed, and enables correct image reproduction.

[0011]

According to the present invention, there is provided an image reading apparatus comprising: a book mounting table for mounting a book at a predetermined position; and a spread placed at the predetermined position on the book mounting table. Holding means for holding the image surface of the book original on a reading surface that is substantially flush with the reading surface, and a reading surface for reading the image surface of the spread original placed at a predetermined position on the book mounting table. The image reading means arranged at a distance of, and the holding means holds the image side of the two-page spread original placed at a predetermined position on the original placement table on the reading surface, and binds the two-page spread original. A book original shape recognizing unit for recognizing a part shape; and an image distortion processing unit for correcting image distortion of a binding unit from a binding part shape of the book original recognized by the book original shape recognizing unit. .

Further, an image reading apparatus according to the present invention comprises:
A book original placing table for placing a book original at a predetermined position, holding means for holding an image surface of a two-page spread original placed at a predetermined position on the book original placing table with a reading surface of substantially the same plane, In order to read the image surface of a double-page spread original placed at a predetermined position on the original document mounting table, image reading means arranged at a predetermined distance from the reading surface, and holding means for reading the original document. A book original shape recognizing means for recognizing a binding portion shape of a spread book original while holding an image surface of the spread original placed at a predetermined position on the table on a reading surface, and a book original shape recognizing means Image density processing means for correcting the image density of the binding portion from the binding portion shape of the book document recognized by the above.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the former image reading apparatus described above, the book original mounting table automatically turns over the pages of the book original and reads the image of the book original. JP-A-6-2531
09 has the same structure as described in Means for Solving the Problems in the Detailed Description of the Invention (No.
(Structures of the inventions described in claims 1 to 9) described in line 31 of the left column of page 5 to line 28 of the column 5 left column 7 are preferable. More specifically, FIG. 2 of Japanese Unexamined Patent Publication No. 6-253109,
2 and FIG. 23, that is, a document table divided into two parts capable of placing portions corresponding to left and right pages of a document at predetermined positions, respectively. It is preferable that the left and right original tables can be independently moved in the vertical direction in accordance with the increase and decrease of the left and right pages, and the original table can form the reading surface.

Using an image sensor comprising a photoelectric conversion element such as a CCD (charge-coupled device) described later, an original reference position for positioning the original by contacting one of the upper and lower edges of the original with the CCD sensor is previously set to the CCD sensor. From the convenience that it is easy to set, it is preferable to arrange a document reference position for positioning by applying one of the upper and lower ends of the original to the original at a predetermined position on the original table. . Here, the end of the book includes the upper or lower end of the book and the upper or lower end of the book. As the original reference position, an original set line is used for setting the original document by touching or aligning the upper or lower edge of the original, but is not limited thereto. For example, a scale or the like that can expand and contract in the thickness direction of the book original may be used.

In the image reading apparatus provided with the automatic page turning reading system as described above, the holding means may be used together with the original plate serving as the book original placing table to constitute the reading surface. Various configurations such as those described in Means for Solving the Problems in the Detailed Description of the Invention in Japanese Patent Application Laid-Open No. 6-253109 (line 31 to 5 in the left column on page 4 of the same publication) It is preferable that the present invention has the configuration according to claims 1 to 9 described on page 28, left column 7, line 28.

The configuration examples of the original document mounting table and the holding means are not limited to those described above, but may be of a system in which the pages of the original document are manually turned and a contact glass is pressed against the face of the two-page spread original. In an image reading apparatus of a manual page turning reading system for reading an image of a document, for example, a configuration similar to that described in Means for Solving the Problems in the Detailed Description of the Invention of Japanese Patent Application Laid-Open No. 6-75308 is the same. It is desirable to have the configuration described in claims 1 to 8 described in line 41 of the right two columns on page 2 of the publication to line 39 of the left three columns of the page 3.

The image reading means comprises an image forming optical system provided with an image pickup element for reading an image of a two-page spread original placed at a predetermined position on the book original mounting table. The image pickup device may be of any configuration and function as described above, i.e., any device capable of providing a later-described function to book document shape recognition means for recognizing a binding portion shape of a spread book document, such as a video CCD as used in cameras
An area sensor or the like may be used. However, in the current state of the art of CCD manufacturing, the number of pixels of the CCD area sensor is at most 400,000 to 800,000, and the image quality is not so good and it is expensive. It is preferable to use a CCD line sensor even if a driving mechanism for moving the contact glass or the like of the image reading means is required, because the image quality is good and the image quality is low.

As an image forming optical system, a reduction optical system is employed. The reduction optical system includes a contact glass for forming a reading surface by abutting an image surface of the book document, a reflection mirror group for reflecting light reflected from the image of the book document, and a reflection mirror for reflecting the image from the reflection mirror group. This is a well-known optical system including an image forming lens for forming an image on a CCD line sensor as an image pickup device. The image reading apparatus is preferably provided with an illuminating means for illuminating the image surface of the book document, and a light source such as a fluorescent lamp is used as the illuminating means.

The original document shape recognizing means detects the CC of the original document end.
The number of pixels between the position of the image forming pixel on the D line sensor and the reference pixel position corresponding to the document reference position is counted, and the document surface distance from the document surface to the reading surface of the binding portion of the book document and the document surface It has the function of recognizing the binding part shape by measuring the inclination. The document shape recognizing unit may be considered as a part of the configuration of the image distortion processing unit from the viewpoint of the control configuration.

When one of the upper and lower edges of the original is aligned with or applied to the original reference position and positioned, depending on how the original is set, the end of the original may deviate from the original reference position and be skewed. May be done. In such a case, the skew amount of each of the left and right pages is obtained from the position of the image forming pixel on the CCD line sensor at the end of the original document, and the reference pixel position corresponding to the original document reference position obtained by subtracting these skew amounts is obtained. By counting the number of pixels between the image forming pixel position at the end of the original document and measuring the original surface distance from the original surface to the reading surface and the original surface inclination of the binding portion of the original document, the binding portion shape is obtained. It is desirable that the original document shape recognizing means be provided with a function of recognizing the document.

The image distortion processing means includes an image correction data storage means for storing the original surface distance data and the original surface inclination data measured by the original original shape recognizing means, and an original image distance data and an original surface inclination data. A correction value table storing means for storing a correction value table preset corresponding to each of them, and performing calculations based on document surface distance data and document surface inclination data and each correction value table, Image correction means for correcting the image distortion of the binding portion from the image correction data obtained by the image expansion process by image expansion processing, and comprising a functional configuration for correcting the image distortion of the binding portion of the book original by the image processing. I have. As the image distortion processing means, a microcomputer including an LSI or the like is used to give each of the above-described functions to each of the above-described control components.

In order to further increase the reading speed, the binding portion shape is recognized in real time by the binding shape recognition means during reading of the binding image, and the image distortion of the binding portion is corrected by the image distortion processing means. Is preferred.

On the other hand, for the former image reading device,
The features of the configuration of the latter image reading apparatus will be described below. The image density processing means corresponds to the image correction data storage means for storing the original surface distance data and the original surface inclination data recognized by the original original shape recognizing means, and the original surface distance data and the original surface inclination data, respectively. A reference table storing means for storing a reference table for density correction which has been set in advance, and calculating based on the document surface distance data, document surface tilt data and the reference table, thereby obtaining the density correction obtained. Image density correcting means for correcting the image density of the binding portion from the data; and a functional configuration for correcting the image density of the binding portion of the book. As the image density processing means, an LSI
Each of the above-described functions is given to each of the above-mentioned control components by using a microcomputer including the above.

In order to further increase the reading speed, the shape of the binding portion is recognized in real time by the book shape recognizing means during reading of the book image, and the image density of the binding portion is corrected by the image density processing means. Is preferred.

The image distortion correction and the image density correction method of the binding portion BOa in the book BO may be performed by image processing after measuring the shape of the book BO as another method different from the above method. Although there are various methods of image interpolation technically, the simplest method is to insert a neighboring pixel.

Further, the image reading apparatus according to the present invention comprises:
Not limited to the former or latter image reading device described above,
An image reading apparatus having both the components of the former and the latter image reading apparatuses described above, that is, an image reading apparatus having both image distortion processing means and image density processing means may be used.

Since the embodiment of the present invention is as described above, Japanese Patent Application Laid-Open No. 6-25 / 1995 provided with the book original mounting table and the holding means in the image reading apparatus of the present invention.
The present invention can be easily applied to the device described in JP-A-3109 or the device described in JP-A-6-75308.

[0028]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings. Throughout the embodiments and the like, configurations and the like having the same functions, shapes, and the like are denoted by the same reference numerals and description thereof is omitted. FIG. 11 shows an image reading apparatus to which the present invention is applied. In FIG. 11, reference BO indicates a book original. This image reading apparatus is an apparatus for reading an image of a book BO, and includes a document table unit 35 and a scanner unit 30 disposed on the document table unit 35 so as to be openable and closable. The scanner unit 30 mainly includes an image reading unit, a first carriage 121, a second carriage 122, and a belt carriage 123, as described later. The first carriage 121 and the belt carriage 123 are supported in a mechanically non-contact state as described later, and are configured to be driven at the same speed in the left and right direction in FIG. 11. For simplicity and convenience, the description will be made assuming that the scanning unit 100 is configured.

The platen unit 35 includes a pair of left and right platens 1, 1 serving as a book platen for placing the book BO at a predetermined position, and a platen at a predetermined position on the platen 1, 1. And a holding means for holding an image surface of the placed double-page spread original BO (hereinafter, sometimes referred to as an original surface) on a reading surface 273 of the same plane.

As described later with reference to FIG. 11, FIG. 12, and FIG.
The contact glass 104 provided on the first carriage 121 and the document pressing rollers 281 provided on the left and right sides of the belt carriage 123 of the scanning unit 100.
a, 281b and document holding sheets 282a, 282b
And a pair of document tables 1, which are divided and arranged left and right.
1, a link plate 10 and a link arm 11 for supporting the original tables 1 and 1 movably in the vertical direction, a torsion spring 13 for urging the original tables 1 and 1 upward, and an original table pressure fixing. It mainly comprises a switching device.

First, the configuration of the document table unit 35 will be described. 11 and 13 (hereinafter, may be abbreviated as each platen 1 or simply platen 1).
As shown in FIG. 15, it is formed of a resin plate having a thickness of 2 mm, and a material having a high coefficient of friction such as extremely thin rubber is adhered to the upper surface thereof. This high coefficient of friction material may be formed on the upper surface of the document table 1 by laminating, coating, spraying, or the like. As shown in FIG. 13, the document table 1 in this embodiment has a document placement surface (upper surface) of A4 size, and is disposed one each on the left and right of the center 2 of the apparatus main body. Have been. A slide plate 3 is fixed below each platen 1. Each slide plate 3 is formed of a sheet metal whose front, rear, and outer surfaces are bent downward.

The original placing surface (upper surface) of each original table 1 is painted black. As shown in FIG. 2 and the like, the front side of the original placing surface of each original platen 1 serves as an original reference position for setting the original BO at a predetermined position by aligning the lower ends of the spread originals BO. Original set line 1S
Is provided. The original set line 1S is the original B
In order to make O easy to set, it is a white linear line having a constant thickness of about 1 to 2 mm and is formed so that its display is not easily erased. The specifications of each platen 1
The maximum thickness of the applicable book manuscript BO is up to 100 mm, and the minimum size of the book manuscript BO is the B6 size.

The lower surface of the slide plate 3 is in contact with the upper surface of the upper and lower bases 5 having a low friction coefficient. The upper surface of the upper and lower bases 5 is formed with a rib of resin such as Teflon so that the upper and lower bases 5 can move relative to the slide plate 3 smoothly left and right. Also, the slide plate 3
And the upper and lower bases 5 are relatively fixed by a size stopper 27 described later. Angles 7a and 7b with long holes in the left-right direction are attached to the lower side of the upper and lower base 5 at four positions in the front-rear and left-right directions. Another angle 8 having a fixed rotation axis and another angle 9 having a long hole in the left-right direction are fixed to the base 6 of the document table unit. Here, a link plate 10 is rotatably supported by the angles 8 and 7b, and a link arm 11 is rotatably supported by the angles 9 and 7a.
With respect to 7b and 9, the link plate 10 and the link arm 11 can smoothly slide in the left-right direction, respectively. Further, as viewed from the entire surface of the document table unit 35, the arm plate 10 and the link arm 11, which are two in each of the front and rear sides, are rotatably supported by the studs 12 at the X-shaped intersections. Also, this stud 12
A torsion spring 13 is hung between the link plate 10 and the link arm 11 around the torsion center, and the torsion spring 13 exerts a force for constantly pushing the upper and lower bases 5 upward in FIG. The elevation of the upper and lower tables 5 due to the upward force is restricted by the document surface of the book document BO set on the document table unit 35 abutting on the scanning unit 100 whose vertical movement is regulated as described later. . As a result, the pressure applied to the scanner unit 30 is maintained substantially constant irrespective of the difference in the thickness of the book document.

The ends of the center 2 of the main body of the two upper and lower bases 5 are connected to each other by a back support plate 14. The back support plate 14 is made of an elastically deformable material such as rubber.
Spine is set. The back support plate 14 is constantly tensioned in the left-right direction by the action of a tension spring 17 described later. That is, the hooks 15 are provided on the upper and lower bases 5, and the hooks 15 and the link plates 1 are provided.
By connecting the 0 angle 16 with the tension spring 17, the pair of left and right upper and lower bases 5 is pulled in a direction away from each other. As a result, tension is always applied to the spine support plate 14, and the spine of the book BO is supported without slack.

On both sides of the base 6, side plates 1 made of sheet metal are provided.
8 is fixed, and a fixing pin 19 on which an open / close lock claw 32 described later of the scanner unit 30 is engaged is attached to each side plate 18.
Has been planted. A leaf spring 21 for pushing the scanner unit 30 upward when the scanner unit 30 is closed, and an open / close lock sensor 20 for detecting the closed state of the scanner unit 30 are attached to one side plate 18. I have.

Next, the size stopper 27 will be described. The size stopper 27 adjusts the interval between the left and right document tables 1 in accordance with the thickness of the book document to be placed, fixes the slide plate 3 (document table 1) and the upper and lower tables 5 relatively, and This is a device for moving the table 1 and the upper and lower tables 5 integrally with each other. 16 and 17 show schematic configuration diagrams of this apparatus. As shown in FIGS. 14 and 16, a pair of angles 22 are attached to the lower side of the upper and lower pedestals 5 at a predetermined interval. These angles 22 include FIG.
As shown in FIG. 6, the rod 23 is horizontally fixed. A sliding body 24 is mounted on the rod 23 so as to slide smoothly in the longitudinal direction of the rod 23 through its own through hole. A short axis 26 is implanted in the slide 24 so as to be orthogonal to the rod 23, and a stopper 25 is rotatably supported on the short axis 26. Here, the stopper 25 extends so that a locking hole 25a formed in one end thereof is loosely fitted to the rod 23, and the other end can be grasped by a finger.

The sliding body 24 is fixed at an arbitrary position on the rod 23 by the inclination of the stopper 25 with respect to the rod 23 and the engagement of the rod 23 with the locking hole 25a of the stopper 25. That is, the slide body 24 is normally tilted by the stopper 25 by the locking spring 28,
Although the rod 23 and the stopper 25 are integrated with each other, the rod 23 is fixed to the rod 23. In FIG. 17, the operator rotates the extended end of the stopper 25 with a finger in a direction against the elasticity of the locking spring 28. By doing so, the engagement between the rod 23 and the locking hole 25 a of the stopper 25 is released, and the rod 23 and the stopper 25 can move along the rod 23. The sliding body 24 is fixed to the slide plate 3 (not shown). Therefore, by fixing the sliding body 24 at a predetermined position of the rod 23 as described above, the slide plate 3 (the document table 1) and the upper and lower tables 5 are moved through the sliding body 24 and the rod 23. It can be fixed at an arbitrary position relatively.

Next, the opening / closing lock mechanism of the document table unit will be described. FIGS. 18 and 19 show schematic configuration diagrams of the opening / closing lock mechanism. As shown in FIGS. 18 and 19, the image reading apparatus of this embodiment has a configuration in which the scanner unit 30 is mounted on the document table unit 35. These units 30 and 35 are connected to each other by a hinge 36 provided on the rear side of the image reading device, and have a shell-type opening / closing structure in which the front side of the image reading device is opened. The opening / closing lock mechanism of the image reading apparatus is disposed at a front part of both units 30 and 35. As described above, the fixing pins 19 are implanted in the side plates 18. Also, as shown in FIG.
The scanner unit 30 has a shaft 31 rotatably supported across left and right side plates.
The open / close lock claws 32 fixed to both ends of the shaft 1 rotate in accordance with the rotation of the shaft 31. An opening / closing lever 33 is fixed near the center of the shaft 31, and by rotating the opening / closing lever 33, the document table unit 35 is moved via the shaft 31 to each of the side fixing pins 19. The opening / closing lock claw 32 is disengaged. A spring 34 is hung on the open / close lever 33, and the spring 34 urges the open / close lever 33 in a direction in which the open / close lock claw 32 is engaged (locked) with the fixing pin 19. As a result, when the scanner unit 30 is closed as shown in FIG. In this closed state, the opening / closing lever 33 is lifted against the urging force of the spring 34, whereby the shaft 31 is rotated, and the opening / closing lock claws 32 are detached from the fixing pin 19 of the document table unit 35, As shown in FIG. 19, the scanner unit 30 is opened upward with the hinge 36 as the center of rotation, and the upper portion of the document table unit 35 (document table 1) is opened.

Next, a description will be given of the platen pressure fixing switching device and the platen retracting device according to the present embodiment. As described above, the document table 1, which is configured to be vertically movable by the link plate 10 and the link arm 11, is constantly biased by the torsion spring 13. Thus, when the scanner unit 30 is closed with respect to the platen unit 35, the platen 1
Is constantly pressed upward so as to press the document surface of the book document BO spread and placed on the document table 1 against the lower portion of the scanner unit 30. The pressing force of the document surface of the book document BO is usually
When the scanning unit 100 is moved to a position outside the book original on the platen 1, the platen 1
In addition, the book document BO digs into the scanner unit 30, and the smooth movement of the scanning unit 100 is hindered. Therefore, with the platen 1 raised to an appropriate position, the platen 1 is fixed to prevent the platen 1 and the book BO from excessively biting into the scanner unit 30 due to the lifting behavior of the platen 1. There is a need to. The document table 1 is placed below the document table unit 35 so that the lower part of the scanning unit 100 does not contact the upper surface of the document table 1.
Need to be evacuated.

The platen pressing / fixing switching device and the platen retracting device are devices provided to achieve the above-mentioned object, and FIG. 11 and FIG. This is shown in FIGS.

As shown in FIG. 20, a control wire 40, which is one of the components of this mechanism, has a hook 4 at one end thereof.
1, another hook 42 is fixed to the other end, and a spherical stop ball 45 is fixed near a substantially central portion thereof. The hook 41 is fixed to an outer end portion of the link plate 10 (a side that moves up and down as the document table 1 is raised and lowered). The control wire 40 extending from the hook 41 changes its direction via pulleys 46 and 47 and is wound around a control pulley 48. Here, the control wire 40
As shown in FIG. 21 and FIG.
The guide ball 45 is guided by the groove 50 and fixed in the vicinity of the central portion thereof. This ensures that the movement of the control wire 40 is converted into a rotational movement of the control pulley 48. The control wire 40 wound around and extended from the control pulley 48 is constantly pulled by one end of a tension spring 43 hooked on a hook 42 at one end thereof. The other end of the tension spring 43 is hooked on a hook 44 fixed to the base 6 of the document table unit 35.

The control pulley 48 is, as shown in FIG.
It is supported by a shaft 54 via a one-way clutch 51. The shaft 54 has a slide bearing 52 supported by a pair of side plates 55, and both ends thereof are prevented from falling off by E-rings 53.
5 is rotatably supported. As a result, the control pulley 48 moves the shaft 54 toward the arrow a in FIG.
However, in the direction opposite to the arrow a, the one-way clutch 51 cannot rotate relative to the shaft 54.
And rotate together. Therefore, when the shaft 54 is fixed by a mechanism described later, the control pulley 48
Is a state in which it can be rotated only in the direction of arrow a in FIG.

Next, the lowering / fixing operation of the original table 1 by this original table pressure fixing switching device will be described.

20 to 22, the shaft 5
When the document table 4 is fixed and the document table 1 is pressed down by some external force, for example, the weight of the book BO or pressurization by a turned page, the document table 1 is fixed to the side. The end of the hook 41 of the control wire 40 is loosened. At the same time, the control pulley 48 is pulled by the tension spring 43 and the hook 41 of the control wire 40 is pulled.
The control wire 40 rotates in the direction of the arrow a while absorbing the looseness of the glue, and the hook 44 moves to the bridle while maintaining the initial tension of the control wire 40. At this time, since the control pulley 48 cannot rotate in the direction opposite to the arrow a due to the action of the one-way clutch 51, even if the lifting force of the document table 1 exceeds the pressing force on the document table 1, The control pulley 48 is not rotated in the direction opposite to the arrow a by the lifting force of the table 1, and the control pulley 48 is stopped while maintaining the position rotated in the direction of the arrow a. Further, along with the stop of the control pulley 48, the movement of the control wire 40 is also stopped, whereby the document table 1 is lowered to a position where it is pushed down by an external force and stopped.

Here, the shaft 54 is fixed by a platen elevating mechanism described below. That is, the gear 56 is fixed to the shaft 54 so as to rotate integrally with the shaft 54 as shown in FIG.
Further, as shown in FIG.
Is engaged with another gear 57 rotatably supported by a stud 59 fixed to the gear 57, and the rotation is transmitted to the gear 57. Further, the gear 57 is formed integrally with the worm wheel 58, and the worm wheel 58 is configured to mesh with a worm gear 60 fixed to an output shaft of a platen elevating motor 61. With this configuration, when the platen elevating motor 61 is stopped, the worm gear 60 is engaged with the worm wheel 58 so that the worm wheel 58
Cannot rotate, and the shaft 54 connected via the gear 56 meshing with the gear 57 integral with the worm wheel 58 is fixed.

Next, the retracting operation of the original table 1 below the original table unit 35 will be described. In FIGS. 11, 23 and 24, when the platen elevating motor 61 is driven so that the gear 56 rotates in the direction of the arrow b, the one-way clutch 51 causes the control pulley 48 and the shaft 54 to rotate integrally. The control pulley 48 rotates in the direction of arrow a in FIG.
Move to the creek. By the movement of the control wire 40, each of the left and right document tables 1 is lowered in FIG.
(In this embodiment, the document surface of the book document BO) is retracted to a position below the document table unit 35, which is separated from the scanning unit 100. This evacuation operation is executed when the power of the apparatus main body is turned on or when the apparatus does not perform scanning.

Next, an operation of pressing the document table 1 above the document table unit 35 will be described. Contrary to the above-described evacuation operation, the gear 5 in FIGS.
6 is rotated in the direction of arrow c so that the platen elevating motor 61
Is driven, the shaft 54 rotates in the direction opposite to the direction of the arrow a in FIG. Here, in the present embodiment, the force of the torsion spring 13 that pushes the document table 1 upward is set to be stronger than the force that pulls the control wire 40 downward. Therefore, in such a state that the control pulley 48 can freely rotate in the direction opposite to the direction of arrow a,
The control wire 40 moves the hook 41 sideways by the force of the torsion spring 13 that pushes the platen 1 upward. By the movement of the control wire 40, the left and right document tables 1 are raised in FIG. You. As described above, when the original table 1 on the left and right sides is raised, and the original table on each original table 1 is pressed against the scanning unit 100 and the motor 61 for the original table is continuously driven, the one-way clutch 51 performs control. The shaft 54 becomes freely rotatable with respect to the pulley 48, and the state of pressing the document surface against the scanning unit 100 is maintained. This pressurizing operation is executed only when the scanning unit 100 is on the document table 1 as described later.

As shown in FIG. 11, one set of the platen pressing / fixing switching device and the platen retracting device are provided for each of the pair of left and right platen plates 1. Each is controlled independently according to the position. That is, a pair of right and left platen elevating motors 61 serving as driving sources of the platen pressing / fixing switching device and the platen evacuation device are connected to respective platen elevating motor drivers (not shown) by a control board (not shown). ) Are controlled independently of each other.

FIG. 25 is a diagram showing the operation of retracting the document table 1 below in the above-described evacuation operation mode, and FIG. 26 is a timing chart thereof. Note that FIG. 25 and FIG.
31 and the like, the shape of the scanning unit 100 is schematically shown in an enlarged and exaggerated manner.

In this retreat operation mode, as shown in FIG. 26, prior to the start of the movement of the scanning unit 100, the right and left platen elevating motors 61 are reversed by a predetermined number of rotations, respectively, as shown in FIG. Then, the left and right original tables 1 are lowered. Thereafter, a scanner motor (not shown) that reciprocates the scanning unit 100 and a second carriage (not shown) described later in the left-right direction in the figure is driven to move the scanning unit 100 in a predetermined direction to perform scanning. .
If necessary, this scanning is repeated many times. At the end of the evacuation operation mode, the left and right platen elevating motors 61 are rotated forward a predetermined number of times, so that the left and right platen
To its original position.

Next, the pressing / fixing mode of the document table 1 will be described.

When the original BO is set on the image reading apparatus, the spine of the original BO is placed on the back support plate 14 as shown in FIG. 27, and the size stopper 27 shown in FIG. 16 is removed. The slide plate 3 is moved according to the thickness of the book BO. By the movement of the slide plate 3, the spine of the book BO is sandwiched between the inner ends of the left and right platens 1. In this state, the respective slide plates 3 are fixed by the size stoppers 27, and then the book BO is The reading start page is opened, the left and right lower ends of the spread book BO are aligned with the document set lines 1S (see FIG. 2), and the spread book BO is placed and set on the left and right platens 1 to set the scanner unit 30. close. Thereby, as shown in FIG.
The opening / closing lock claw 32 is engaged with the fixing pin 19, and is locked with the scanner unit 30 closed with respect to the document table unit 35. At this time, the opening / closing lock sensor 20 detects that the scanner unit 30 is closed.

By the way, at the end of the operation of the image reading apparatus, the scanning unit 100 returns to the center home position (the center point of the set book BO) shown in FIG. Therefore, also when the book BO is set on the image reading apparatus, the scanning unit 100 is located at the center home position. As a result, the book BO is set with reference to the center of the image reading apparatus, and when the scanner unit 30 is closed,
A book of any size can be reliably pressed, and the setting of the book can be improved. Also, by setting the book original as the center reference in this manner, the control timing (reading start; reading end timing, page turning start timing, etc.) when turning the read page of the book original on the platen 1 is relatively controlled. Easy to take. further,
By setting the book original as the center reference in this manner, the edge of the book original can be easily detected.

In this embodiment, a document set line 1S (see FIG. 2) which is a document reference position on the document table 1 is configured such that the front side of the apparatus main body is used as an abutment reference.
The document setting operation on the document table 1 is facilitated.

Further, the scanning unit 10 according to the present embodiment is
At the start of the zero operation, the center HP sensor 190 confirms again that the scanning unit 100 is at the center home position.

When a start signal is sent from an operation display control unit (not shown), the scanning unit 100
It moves leftward from the center home position and stops at the end home position detected by the end HP sensor 191.

FIGS. 27 to 31 show transition diagrams of the scanning unit 100 in the pressing / fixing mode of the document table 1, and FIG. 32 shows a timing chart thereof.

As shown in FIG. 27, the scanning unit 100
Is an operation start point of the page turning operation for reading the original BO and an operation end point thereof. Further, at this end home position, the scanning unit 100 does not rest on the document table 1.
In the pressing / fixing mode of the document table 1, first, the scanner motor of the scanning unit 100 is rotated forward to move the scanning unit 100 rightward in FIG. Next, when the right document pressing roller 281a of the scanning unit 100 is applied to the left end of the book BO (point A in FIG. 28), the left document table elevating motor 61 is rotated forward, and the left document table 1 is rotated. To a pressurized state. As a result, the original B
O is pressed against the scanning unit 100 to perform optimal image reading. Then, as shown in FIG.
Shortly before the scanning unit 100 reaches the book document center point, the right document pressing roller 281a is applied to the left end of the right document table 1 (point B in FIG. 32). At this time, the right platen elevating motor 61 is rotated forward to put the right platen 1 in a pressurized state. Next, the scanning unit 100
Starts reading the right-hand page of the book BO after passing through the book center point. Thereafter, the left document pressing roller 281b is applied to the right end of the left document table 1 (C in FIG. 32).
point). At this time, the left platen elevating motor 61 is stopped, and the left platen 1 is fixed. As a result, the book document BO is pressed and fixed by the document pressing sheet 282b without biting into the scanner unit 30,
The same height is maintained until the next scanning unit 100 passes.

FIG. 30 shows an operation state of the scanning unit 100 during reading or turning of the right page of the book. Scanning unit 100 after reading the right page of the book
31 is stopped in a state where the left document pressing roller 281b is over the right end of the right document table 1 (point D in FIG. 32), and then the scanner motor is reversed to move the scanning unit 100 leftward in FIG. Let it. As a result, the scanning unit 100 moves leftward while turning over the right page of the book BO, and slightly before reaching the book central point shown in FIG. 29, the left document pressing roller 281b moves the left document table 1 (C point). At this time, the left document table lifting / lowering motor 61 is rotated forward to put the left document table 1 in a pressurized state. Next, the scanning unit 100
Starts the operation of passing the turned right page over the left page of the book BO after passing through the book manuscript center point. Thereafter, the right document pressing roller 281a is applied to the left end of the right document table 1 (point B). At this time, the right platen elevating motor 61 is stopped, and the right platen 1 is fixed. As a result, the book BO can be pressed without touching the scanner unit 30.
a, and is kept at the same height until the next scanning unit 100 passes. Thereafter, the scanning unit 100 moves to the end home position shown in FIG. 27 and stops.

Next, the configuration of the scanner unit 30 in this embodiment will be described with reference to FIGS. 11, 12, and 36. As shown in FIGS. 11 and 12, the scanner unit 30 mainly includes an image reading unit, a first carriage 121, a second carriage 122, and a belt carriage 123. As shown in FIG. 11, an upper half of the apparatus main body of the image reading apparatus is a scanner unit 30. As described above, the scanning unit 100 including the first carriage 121 and the belt carriage 123 Unit 3
0 in the left and right direction in FIG.
O scanning is performed.

First, referring to FIGS. 33 to 35, the first
A drive transmission system of the carriage 121, the second carriage 122, and the belt carriage 123 will be described. The drive transmission system has two components. FIG. 33 is a diagram showing the driving and running of the belt carriage 123 viewed from the top of the apparatus main body.
A first drive transmission system for scanning, and a first carriage 1
21 and a second drive transmission system for driving and scanning the second carriage 122, respectively.

The first drive transmission system includes the scanner unit 30
In the drawing, a scanner motor 143 which is disposed on the near side of the right end and has a first drive pulley 144a on its output shaft.
In the main scanning direction S near the scanner motor 143.
And a second end at the front end of the apparatus body.
A wire pulley shaft 140 having a driving pulley 144b and a third driving pulley 144c, and a first driving pulley 144a.
And a second drive pulley 144b, and a first drive belt 145a extending in parallel with the wire pulley shaft 140 in the vicinity of the scanner motor 143, a large-diameter timing belt pulley 146a and a small-diameter The second drive belt stretched between a fourth drive pulley 144d, a belt pulley shaft 147 having a large-diameter timing belt pulley 146c at the other end, and a third drive pulley 144c and a fourth drive pulley 144d. 145b
And timing belt pulleys 146b and 146d pivotally disposed on the front and rear sides of the left end in the drawing of the scanner unit 30, between the timing belt pulleys 146a and 146b, and the timing belt. It is composed of timing belts 148 and 148 respectively stretched between a pulley 146c and a timing belt pulley 146d. The front side and the back side of the belt carriage 123 are fixed to timing belts 148, 148 via belt clamps 149, 149.

Since the first drive transmission system is configured as described above, the rotational driving force of the scanner motor 143 is the first drive transmission system.
The power is transmitted to the driving pulley 144a, the first driving belt 145a, the second driving pulley 144b, and the wire pulley shaft 140 in this order. The rotational driving force of the scanner motor 143 is further transmitted to the third driving pulley 144c, the second driving belt 145b, the fourth driving pulley 144d, and the belt pulley shaft 147 in this order, so that the belt carriage 123 It travels in the scanning direction F.

Next, the second drive transmission system will be described.
The second drive transmission system transmits the rotational driving force of the scanner motor 143 transmitted to the wire pulley shaft 140 to the first carriage 121 and the second carriage 122 by two drive wires on one side and a plurality of wire pulleys described later. It is. The detailed wiring state of the driving wires is shown in FIGS. 34 and 35, and the detailed wiring state of the driving wires is omitted in FIG.

A stop ball 13 is provided at one end of the drive wire 134a.
A stop ball 134a2 is formed at the other end, and a wire stopper 136 is formed and fixed to the drive wire 134a between the stop ball 134a1 and the stop ball 134a2. On the other hand, a stop ball 134b1 is formed at one end of another drive wire 134b, and the other end is hooked and connected to a tension spring 155. A pair of two-groove pulleys 137, 137 for winding the drive wire 134a and the drive wire 134b in directions opposite to each other are formed on the front and rear side walls of the second carriage 122.
Is supported. A pair of wire pulleys 139, 139 are fixed to the near side and the far side of the wire pulley shaft 140, as shown only in the near side in FIGS. Each wire pulley 139 has a thread-wound cylindrical shape, while its outer end and inner end extend in the radial direction to form a flange, and the outer end flange is for locking a stop ball 134a1 of the drive wire 134a. A locking groove 139a is formed in the inner end flange, and a locking groove 139b for locking the stop ball 134b1 of the drive wire 134b is formed in the inner end flange.

The wire stopper 13 of the driving wire 134a is provided on the front and rear side walls of the first carriage 121.
6, a pair of flat wire holders 13 for fastening
5, 135 are formed to project outward. Timing belt pulleys 145a, 146b, 146c, 1
A pair of pulleys 138b and 138c and a pair of pulleys 138 that are independently supported on the scanner unit 30 in the vicinity of the inside of the four corners provided with the pair 46d are supported independently.
a, 138d are provided respectively.

The front and rear drive wires 134a, 134
Since the arrangement state of 4b is the same, only the near side will be described. As shown in FIGS. 34 and 35, one end of the drive wire 134a is connected to a stop ball 134a1 at one end thereof.
Is locked in the locking groove 139 a of the wire pulley 139, and is wound around the wire pulley 139. Drive wire 1
The other end of 34a is fastened to the first carriage 121 by engaging the wire stopper 136 of the drive wire 134a with the wire holder 135 of the first carriage 121 on the way to the two-groove pulley 137 via the pulley 138b. ing. The other end of the drive wire 134a is fixed by changing its direction with a two-groove pulley 137 and locking the stop ball 134a2 to the main body structure of the scanner unit 30 via a pulley 138c.

On the other hand, at one end of the other drive wire 134b, a stop ball 134b1 at one end is connected to the wire pulley 1b.
It is locked in 39 locking grooves 139b and is wound around the wire pulley 139. The other end of the drive wire 134b is turned by a two-groove pulley 137 via a pulley 138a, and the tension spring 15 is pulled via a pulley 138d.
5 and is fixed to the second carriage 122.

Since the second drive transmission system is configured as described above, the rotational driving force of the scanner motor 143 is transmitted along the second drive transmission system by rotating the wire pulley shaft 140, and The carriage 121 and the second carriage 122 travel and scan in the left and right directions in the figure.

Since the first drive transmission system and the second drive transmission system are configured as described above, the first carriage 121 travels and scans in the same direction at the same speed as the belt carriage 123, and further the second carriage 122 first
The carriage can travel and scan at half the speed of the carriage 121. Thus, the first carriage 121 and the second
The carriage 122 is substantially one drive wire (134
a, 134b) to drive the scanner motor 143, which is a drive unit, when the first carriage 121 and the second carriage 121
The drive wires 134a and 134b are routed so that the carriage 122 runs and scans at a speed of 2: 1. The conjugate length adjustment of the imaging optical system is substantially performed on one drive wire (134a and 134b). The scanning speed of the first carriage 121 is not affected even when the scanner motor 143 is rotationally driven. Therefore, even if a new driving unit is added, the image on the original surface of the original BO can be scanned at a precise speed, and the scanning is performed by substantially one driving wire (134a, 134b). ,
The mechanism is very simple.

Next, referring to FIGS. 11, 12, and 36, the image reading means, the first carriage 121, the second
The detailed configurations of the carriage 122 and the belt carriage 123 will be described. The first carriage 121 and the second carriage 122 have a part of the configuration and function of the image reading unit. The first carriage 121 includes an illuminating unit for illuminating the original surface of the two-page spread original BO. Has functions. The belt carriage 123 has the configuration and function of a page turning unit that automatically turns pages of a two-page spread original BO, and the configuration and function of a part of the holding unit. First carriage 121 and belt carriage 12
3 are mechanically supported in a non-contact state with each other via vibration preventing dampers 125, 125 disposed between the left and right upper and lower portions, so that the vibrations are not transmitted to each other. Has become.

The image reading means is arranged at a predetermined distance from the reading surface 273 in order to read the face of the double-page spread original BO placed at a predetermined position on the document table 1. FIG. 11 and FIG.
As shown in FIG. 6, C as an image sensor for reading an image of a two-page spread original BO placed at a predetermined position on the original platen 1
An imaging optical system having the CD sensor 101 is provided.

The CCD sensor 101 is attached and fixed to a predetermined position shown in FIGS. 11 and 36 of the main body structure of the scanner unit 30 via an immovable member (not shown).
The CCD sensor 101 is a semiconductor photoelectric conversion element, and in this embodiment, a line sensor is used. The CCD sensor 101 has a resolution of 400 DPI and a number of pixels of 5000.

The image forming optical system includes a first carriage 121
A contact glass 104 disposed at the lower part of the inside;
The figure of the 1st mirror 108 arrange | positioned above the contact glass 104 in the carriage 121, the 2nd mirror 110 and the 3rd mirror 111 arrange | positioned in the 2nd carriage 122, and the figure of the main body structure of the scanner unit 30. 1
36 and a lens 1 attached to a predetermined position shown in FIG.
06 and the CCD sensor 101 described above.

As shown in detail in FIG. 12, the first carriage 121 is disposed so as to be fitted between the original pressing roller 281a and the turning belt driving roller 223 of the belt carriage 123. First carriage 1
Reference numeral 21 denotes the above-mentioned contact glass 104 and a pair of left and right fluorescent lamps 105, 105 serving as light sources as illumination means.
(Hereinafter, simply referred to as a fluorescent lamp 105), the first mirror 108 described above, and a dustproof glass 124. The inside of the first carriage 121 has a substantially sealed structure to prevent intrusion of dust and the like.
The contact glass 104, the first mirror 108, and the fluorescent lamp 105 are disposed in the main scanning direction orthogonal to the sub-scanning direction F so as to extend at least longer than the largest readable original BO. I have.

The fluorescent lamp 105 is a contact glass 104
, And are disposed on the left and right ends of the book reading section, respectively. These fluorescent lamps 105 pass through the contact glass 104 from above the right and left sides of the original B.
O is exposed to eliminate unevenness in density due to left and right pages when reading the image of the book BO and shading of the binding portion BOa of the book BO. As the fluorescent lamp driving system, there are various systems as proposed by the present applicant in Japanese Patent Application Laid-Open No. Hei 6-253109, but in the fluorescent lamp driving system of the present embodiment, the image reading and scanning of the original BO is performed. An exposure method is employed in which the set exposure light value is kept constant from the start.

The contact glass 104 is provided at the lowermost reading slit position in the first carriage 121, and the lower surface position of the contact glass 104 is as shown in FIG.
As shown in the figure, a horizontal plane formed by connecting the lowermost point of the left original pressing roller 281b and the lowermost point of the turning-belt driving roller 223 in advance in consideration of a margin for lifting the original surface of the original BO. It is set above the surface 273) by a slight gap α. The value of this gap α is 2α
Is set to be equal to or less than the depth of focus of the imaging optical system, and is determined according to the reduction ratio of the optical system.

As shown in FIG. 40, the contact glass 104 has a side portion supported by a glass holder 269. Further, a glass chamfered portion 271 is provided at the lower end of the contact glass 104, and a holder chamfered portion 270 is provided at an outer lower end of the glass holder 269. At this time,
The position of the side corner portion 272 of the glass chamfered portion 271 is configured to be located above the lower surface of the glass holder 269 by a slight height β, and the side of the contact glass 104 during the operation of the scanning unit 100. The end of the page of the book manuscript is prevented from being caught on the cover.

The second carriage 122 is formed in a housing shape that is long in the main scanning direction. Second carriage 12
Reference numeral 2 denotes a second mirror 110 for further reflecting the image of the document surface of the book BO reflected by the first mirror 108 of the first carriage 121 through upper and lower openings of the housing and guiding the image to the lens 106. The third mirror 111 is supported at a predetermined position in the figure.

The image of the original surface of the original BO which is opened and placed and set and fixed on the original table 1 with its original surface facing upward is illuminated by each fluorescent lamp 105, and the above-mentioned second drive transmission system The second carriage 122 is scanned at half the speed of the first carriage 121 by the operation described above, so that the light is reflected by the first mirror 108 in FIGS. 3 reflected by the mirror 111 and finally transmitted through the lens 106,
A / A which is reduced and imaged on the D sensor 101 and is not shown
It can be obtained as a digital image signal via a D converter. The details of the image processing reduced and formed on the CCD sensor 101 will be described later.

Next, the detailed structure of the belt carriage 123 will be described. In FIG. 12, the belt carriage 123
Document holding rollers 281a and 281b
On the outside thereof, a sheet take-up roller 280 is provided.
a and 280b are each rotatably supported by the shaft.
The left and right independent document holding sheets 282a and 282b are wound around the center ends of the sheet pressing rollers 280a and 280b, respectively. The outside ends of the document holding sheets 282a and 282b are , Are fixed to side plates of the scanner unit 30, respectively. These document holding sheets 282a and 282b are formed of sheet-like members in which a rubber-based resin is melted from both sides into a cloth (cloth) woven with tetron yarn. It has a structure in which the attraction force due to charging hardly acts.

The sheet take-up rollers 280a, 280a
As shown in FIG. 37, one of the winding rollers 80b has a double structure, and the winding roller shafts 251a and 251
b, cylindrical sheet take-up rollers 280a, 280b
The mainspring springs 252a and 252b are mounted between the mainsprings. Thereby, the take-up roller shaft 251
By rotating the document holding sheets a and 251b further than the state where the document holding sheets 282a and 282b are stretched, a certain amount of tension can be applied to the document holding sheets 282a and 282b by the action of the mainsprings 252a and 252b.

Further, as shown in FIG. 38, sheet winding gears 232a and 232b are fixed to the outer ends of the winding roller shafts 251a and 251b, and these sheet winding gears 232a and 232b are The right and left ends are fixed to the side plate of the scanner unit 30 and mesh with a drive rack 231 having teeth over substantially the entire length via idle gears 233a and 233b. Accordingly, when the scanning unit 100 travels in FIG. 38, the sheet winding gears 232a and 232b rotate together with the idle gears 233a and 233b,
Each document pressing sheet 282 is passed through each of the take-up roller shafts 251a and 251b, each of the mainspring springs 252a and 252b, and each of the sheet take-up rollers 280a and 280b.
a and 282b are pulled out and taken up, and the tension of the left and right sheet take-up rollers 280a and 280b is always maintained substantially constant. At this time, each document pressing sheet 28 wound around each of the sheet take-up rollers 280a and 280b generated by the position of the scanning unit 100 due to the thickening of each of the sheet take-up rollers 280a and 280b due to the thickness of each of the document press sheets 282a and 282b.
The outer peripheral difference between 2a and 282b is different from that of each spring 252a,
252b.

As described above, the contact glass 104 for reading the original in the present embodiment is located upstream of the scanning unit 100 in the scanning direction, and the turning belt 208 for turning the pages of the original is located in the scanning unit 1.
00 are arranged on the downstream side in the scanning direction. By arranging in this way, the run-up section for the reading scan of the scanning unit 100 can be lengthened,
The scanning can be stabilized. Further, in this embodiment, the page turning mechanism is arranged on the lower side in the same unit, and the reduction optical system is arranged on the upper side, thereby realizing the miniaturization of the apparatus.

Further, with this configuration, the scanning unit 100 receives the book original (details will be described later) pressed by the left original pressing roller 281b and the turning belt drive roller 223, and receives these originals. Since the document surface (reading surface 273) positioned between the rollers can be read, an optimal image can be obtained.

Further, the turning belt 208 is stretched over a turning belt driving roller 223 and a turning roller 224, and an upper portion of the turning belt 208 and a portion slightly away from the turning belt driving roller 224 is provided outside.
The charging roller 225 is disposed in contact with the charging roller 225. The charging roller 225 can charge the surface of the turning belt 208 by a charging device, as described in an operation described later with reference to FIG. The turning belt 208 and the turning roller 224 are configured to be displaceable and switchable between a broken line position and a solid line position shown in FIG. 12 by a solenoid (not shown).

Further, as shown in FIG. 38, a turning belt driving gear 234 is fixed to the end of the driving shaft of the turning belt driving roller 223. The turning belt driving gear 234 is connected via an idle gear 235. , And the drive rack 232. Thus, when the scanning unit 100 travels, the turning belt driving gear 234 rotates along with the idle gear 235 along the drive rack 232, and the turning of the turning belt driving roller 223 turns the scanning unit 100 at the same speed as the moving speed of the scanning unit 100. The belt 208 rotates.

The turning belt 208 in this embodiment is
The material is made of PET, PC, PVC, etc., and its surface layer is a high-resistance film with a surface resistance of 10 ¹⁴ Ω or more, and its back layer is a double-layer resin film with a low-resistance film with a surface resistance of 10 ⁸ Ω or less. It is configured.

The turning-belt driving roller 223 is formed of a grounded metal roller coated with a conductive rubber on the surface thereof, and realizes reliable belt driving and grounding. The charging roller 225 is formed of a metal roller. As shown in FIG.
A high voltage of ± 2 kV is applied at a predetermined timing from the changeover switch 253a and the AC power supply 253 constituting the charging device.

In FIG. 41, while the scanning unit 100 is running and the turning belt 208 is driven, the changeover switch 253a is turned on at the timing described later, and a high voltage of ± 2 kV is applied to the charging roller 225 from the AC power supply 253. An alternating electric field is generated on the surface of the turning belt 208, and the action of the alternating electric field causes the uppermost page 2 of the book BO to come into contact with the surface of the turning belt 208.
An attracting force for attracting 54 is generated.

Next, the page turning operation of the scanner unit 30 will be described with reference to FIGS.
In each of the drawings used to explain the operation, the first carriage 12
1 and the scanning unit 100, the entire left and right widths in the scanner unit 30 are shown in a reduced manner. In addition, the second carriage 122 and the like are omitted to simplify the drawing.

FIG. 41 is a view for explaining the operation of the page turning section of the scanning unit 100 in this embodiment. In the figure, the scanning unit 100 is run and the turning belt 20 is turned on.
When the changeover switch 253a is turned on in accordance with the timing described later while driving the driving roller 8 and a high voltage of ± 2 kV is applied to the charging roller 225 from the AC power supply 253, an alternating electric field is generated on the surface of the turning belt 208, and the alternating electric field is generated. Due to the action of the electric field, an attraction force is generated on the surface of the turning belt 208 to attract the uppermost page 254 of the book BO in contact.

When the image reading operation of the book BO is started, as shown in FIG.
The second carriage 122 (not shown), the first carriage 121, and the belt carriage 123 (scanning unit 100) at the home position at the left end of FIG.
Start running rightward at. When the original reading position of the contact glass 104 of the scanning unit 100 is on the left page of the book BO, as shown in FIG. 42, the imaging optical system starts an image reading operation of the book BO. The manuscript surface of the book manuscript BO is read from the left page to the right page. At this time, when reading the document surface of the binding portion of the book BO, characteristic image distortion and image density correction processing of the present invention are performed, and details thereof will be described later.

The reading start position of the scanning unit 100 here varies depending on the size of the book BO. In this way, when the imaging optical system of the scanner unit 30 finishes reading to the right end of the book BO,
As shown in FIG. 43, the scanning direction of the original of the scanning unit 100 is reversed, and as shown in FIG.

When starting to turn the pages of the book BO, the turning belt 208 and the page feed roller 25 to be described later are used.
0 is located at the position shown by the broken line in FIG. 41, and prior to this page turning operation, the charged pattern portion formed on the surface of the page turning belt 208 has the uppermost page 25 of the book BO.
Overlap 4 Then, as shown in FIG. 44, when the leading end of the uppermost page 254 exceeds the lower center of the turning belt 208, the turning belt 208 and the page feed roller 250 are connected to the solenoid (not shown). Is moved to the position shown by the solid line in FIG. As a result, the book original BO is formed by the attraction force of the charge pattern formed on the surface of the turning belt 208 due to the uneven electric field.
Is attracted onto the surface of the turning belt 208, and the end of the top page 254 is lifted together with the turning belt 208. The attraction force due to the uneven electric field has a characteristic that pages other than the top page 254 are not attracted.

Here, the turning belt 2 in this embodiment is used.
As shown in FIG. 48, the timing of the charging to 08 is set so that the charging of the turning belt 208 is started together with the return operation of the scanning unit 100 which returns at the same time as the completion of reading the document surface of the book BO. Because
The operation of the scanning unit 100 is efficient without waste. However, as shown in FIG. 48, the distance L1 from the original reading position of the scanning unit 100 to the lowermost point of the turning belt driving roller 223 is determined by the charging roller 225 by the turning belt 2.
08 and the belt drive roller 22
3 is larger than the distance L2 to the lowest point (L1 ≧ L2)
In this case, it may be set so that after the scanning unit 100 starts the return operation, charging of the turning belt 208 is started later.

As described above, the uppermost page 25 of the book BO
After turning up the scanning unit 4, the scanning unit 10 remains in this state.
0 is moved toward its end home position as shown in FIG.
45, a pair of upper and lower page guides 22 disposed on the right side of the scanning unit 100 are reliably transported by being sandwiched between the turning roller 224 and the page feed roller 250, as shown in FIG.
7, 228 (see FIG. 12), the leading end of the scanning unit 100 is sent to the right outside. At this time, the page guide 227 on the upper side of the scanning unit 100
Page turn sensor 214 mounted on top (see FIG. 12)
Detects the original page sent to the right outside of the scanning unit 100, and determines that the original page has been normally turned.

As is apparent from the above description, in this embodiment, the original page turned up by the page turning operation of the scanning unit 100 is held in a natural posture without being rounded or bent. There is no need to arrange the turned-up original pages in the scanning unit 100 without damaging the turned-up original pages, and the scanning unit 100 can be downsized.

Next, as shown in FIG.
When the top page 254 is turned up to the binding portion of the book original, the turning belt 208 and the page feed roller 250 are returned to the original positions (broken line positions in FIG. 41). In this state, when the scanning unit 100 is further moved toward the end home position, as shown in FIG. 47, the turned-up original page is pulled by the binding section of the book original and a pair of page guides is provided. While returning between 227 and 228, the original BO is discharged from the scanning unit 100 so as to be superimposed on the left page.

When the turned-up original pages are all superimposed on the left page of the book original BO, the scanning unit 100 finishes one original reading / page turning operation for a two-page spread original. Here, this book manuscript BO
As described above, when repeatedly performing the document reading / page turning operation on the document, or repeatedly performing only one of the document reading and the page turning operation,
The turning direction of the scanning unit 100 is reversed at the same time when the turned-up original pages are all superimposed on the left page of the book original BO, and the reciprocating operation of the scanning unit 100 is performed in the shortest course with respect to the original surface of the book original. repeat.

Next, the first carriage 1 in this embodiment is described.
21, second carriage 122, belt carriage 123
The structure of the carriage supporting means for respectively supporting the components will be described. The first carriage supporting means and the belt carriage supporting means substantially regulate the respective positions of the first carriage 121 and the carriage 123 in the vertical direction above each document table 1, and are mounted on each document table 1. The first carriage 1 is slidably movable with respect to the document surface of the book
21, which has a configuration function of supporting the belt carriage 123. Specifically, FIGS. 78 and 79 of JP-A-6-253109 previously proposed by the present applicant.
Are the same as the configurations of the scanning rail and the holding roller in the support structure and support mechanism of the scanning unit 200 shown in FIG.

The first carriage 121 and the belt carriage 123 are composed of two parallel scanning rails (not shown) fixed to a pair of scanning side plates (not shown) disposed on the near side and the far side of the scanner unit 30, respectively. (Not shown), the positioning roller and the press roller supported on the front and rear side walls of each of the first carriage 121 and the belt carriage 123 are rotatably provided, so that the reading surface 273 and the reading roller 273 can be rotated. It is configured to be movable in parallel in the sub-scanning direction. The pressing roller presses the horizontal portion of each of the scanning rails from above by a contracting force of a pressing spring (not shown). The first carriage 121 and the belt carriage 123 are given a disposition toward the upper side of the scanner unit 30 by the pressing of the holding rollers against the horizontal portion of each of the scanning rails. The first carriage 121 and the belt carriage 123 are independently positioned with respect to the scanner unit 30 by the respective positioning rollers contacting the lower surface of the horizontal portion of the rail.

The second carriage 122 is provided with the first carriage 122.
The carriage is configured to be movable in the sub-scanning direction in parallel with the reading surface 273 by a supporting structure and a supporting mechanism substantially similar to those of the carriage supporting means and the second carriage supporting means.

FIGS. 49 to 52 show page feed rollers 25.
0 shows the configuration and operation.

FIG. 49 and FIG.
As shown in FIG.
A plurality of rollers are fixed to a portion corresponding to a width of 8 at a predetermined interval. This page feed roller 2
Reference numeral 50 is formed of a soft resin such as polyurethane foam or a material such as rubber.

On the other hand, the width of the turning roller 224 is formed to be larger than the width of the turning belt 208, as shown in FIG.
As shown in (2), both ends of the turning roller 224 extend outside the turning belt 208. Drive rollers 249 each having a diameter slightly smaller than the diameter of the page feed roller 250 are fixed to the shaft 248 so as to correspond to the extending portions at both ends of the turning roller 224. The drive roller 249 is provided with a page feed roller 250.
It is formed of a material such as rubber having higher hardness.

When the page feed roller 250 is retracted to the position shown by the broken line in FIG. 41, the tip fits into the concave portion of the lower page guide 228 formed in a comb shape (when viewed from the side). (Overlapping each other).
When the turning belt 208 is raised to the position shown by the solid line in FIG. 41, the page feed roller 250 also moves to the position shown by the solid line in FIG. In contact with each other, a part of the peripheral surface of the page feed roller 250 moves to a position where it is slightly pressed by the turning belt 208.

As a result, the page feed roller 250 is
As shown in FIG. 0, the page feed roller 250 is provided with a conveying force for the original page turned up by the turning belt 208 by being deformed by the diameter difference from the driving roller 249. Further, the rotational force on the page feed roller 250 is given by transmitting the rotational force of the turning roller 224 via the driving roller 249 abutting on the same. At this time, the driving roller 249 rotates at the same peripheral speed as the contacting turning roller 224, but the page feed roller 250 rotates at a higher peripheral speed by an amount larger than the diameter of the driving roller 249. As a result, “the linear velocity of the page feed roller ≧ the linear velocity of the turning belt” is satisfied, and
A reliable page conveying force for the turned-up original page is obtained.

On the other hand, as shown in FIG. 47, when the turned original page is discharged from the belt carriage 123, the page feed roller 250 and the turning belt 208 are used.
Are retracted to the positions indicated by the broken lines in FIG.

The page feed roller 25 configured as described above
The operation of 0 is controlled by the toggle joint device shown in FIGS. 51 and 52. As shown in FIGS. 51 and 52, a shaft 248 which is the center of rotation of the page feed roller 250 is a toggle lever 2 formed in a bell crank shape.
74 is rotatably supported at one end. The toggle lever 274 moves the fulcrum 27 with respect to the scanning unit 100.
5 is rotatably supported. Scanning unit 1
A tension spring 279 is stretched between the fixing pin 276 and the shaft 248 implanted in the shaft 00, whereby a straight line passing through the fixing pin 276 and the fulcrum 275 is set to a neutral line 278. A mechanism is configured.

In this toggle mechanism, as shown in FIG. 51, the page feed roller 250 is retracted from the turning belt 208 to the position shown by the broken line in FIG. 41, and the turning roller 224 is shown by the solid line in FIG. When the ascent is started toward the position shown in FIG.
Engages with the other end of the toggle lever 274 and further rises while rotating the toggle lever 274. At this time, the rotation of the toggle lever 274 causes the shaft 2
Until 48 exceeds the neutral line 278, the contracting force of the spring 279 attempts to return the page feed roller 250 to its original position. , And acts so as to bring the page feed roller 250 into contact with the turning roller 224. As a result, as shown in FIG.
When the spring 27 has been lifted to the position shown by the solid line in FIG.
Due to the contraction force of No. 9, each drive roller 249 comes into contact with each end extending portion of the turning roller 224 and moves to a position where a part of the peripheral surface of the page feed roller 250 is slightly pressed by the turning belt 208. .

On the other hand, as shown in FIG. 47, when the turned-up original page is discharged from the scanning unit 100,
Due to the operation of retracting the turning roller 224 to the position shown by the broken line in FIG. 41, the turning roller 224 descends from the position shown in FIG. 52 while pressing the drive roller 249.
As a result, when the shaft 248 crosses the neutral line 278, the contracting force of the spring 279 acts in a direction to retract the page feed roller 250 to the position shown by the broken line in FIG. The turning roller 224 is returned to the original position.

As described above, the page feed roller 250 in the present embodiment moves from the retracted position in the direction in which it comes into contact with the turn belt 208 in conjunction with the upward drive of the turn belt 208. Can be configured inexpensively and compactly. The movement of the page feed roller 250 is started with a certain time lag (in the latter half of the rise of the turning belt 208) after the turning belt 208 starts to move up.
Even if the end of the original page turned up by the rise of the sheet 8 protrudes from the turning belt 208, the end of the original page is securely sandwiched between the turning belt 208 and the page feed roller 250. As a result, the margin of the page turning operation of the scanning unit 100 is improved.

Next, with reference to FIGS. 1 to 5, a description will be given of a method of correcting image distortion at a binding portion of a book document. In this image reading apparatus, as schematically shown in FIGS. 1 and 3, a reduction optical system is used as the imaging optical system shown in FIG. 11 and the like, and 1 to n pixels (the number of pixels is Using the CCD sensor 101 which is a line sensor having n = 5000), the image of the book BO is scanned by scanning the document surface of the book BO in the horizontal direction.

When reading the image on the original surface of the original BO, first, as shown in FIG. 2A, a display is performed to place and set the original BO at a predetermined position on each original table 1. The spread book BO is placed and set on each platen 1 with the lower ends of the spread book BO aligned with the outer parting line of the document set line 1S as the document reference position. In this embodiment, the CCD sensor 101
Are set in advance in the original document shape recognizing means of the image processing unit described later, corresponding to the outer parting line position in the original set line 1S.

The original reference position is not limited to the above-described original set line 1S.
Of course, it may be the inner parting line in S. In short, the parting line may be formed so that it can be set in advance in the original document shape recognizing means of the image processing unit described later.

As shown in FIG. 2 (b), the right and left pages of the two-page spread original BO placed at a predetermined position on each original table 1 are flush with each other by the action of the above-mentioned holding means. The original book BO is held so as to form a reading surface 273 serving as a reading surface 273, and the left and right pages are pressed against the contact glass 104 (not shown) to read an image. By doing so, as described above, the binding portion B
An image on the document surface that is read in close contact with the contact glass 104 (not shown) other than Oa can be read without image distortion.

However, since the image on the document surface of the binding portion BOa is farther than the position of the normal reading surface 273 which is read without image distortion, the image in the main scanning direction S
, And the document surface is inclined in the sub-scanning direction F by tilting. Here, as shown in FIG. 3, the relationship between the document surface depth h, which is the document surface distance from the document surface of the binding portion BOa to the reading surface 273, and the amount of contraction c in the main scanning direction S is the same as in the present embodiment. When the conjugate length L of the imaging optical system, the image height G, and the reduction ratio m, h = cL / ((Gc) (1 + m)) (1).

In the equation (1), the conjugate length L and the contraction rate m are constants as characteristic values of the imaging optical system in this embodiment, and the original surface depth h, the image height G, and the contraction amount c are: Will be related to each other.

Also, as shown in FIGS. 1, 2 and 4, the lower end of the two-page spread original BO is aligned with the original set line 1S, and the original set line 1S
A pixel a set as a reference pixel position of the CCD sensor 101 corresponding to the pixel b and a pixel b projected at the lower end of the book BO
By counting the number d of pixels between the two, the contraction amount c can be obtained by the equation c = pd / m (2) with the code p as the pixel pitch.

Based on the relationship between the contraction amount c of the document boundary obtained by the expression (2) and the above expression (1), the depth h of the document surface from the document surface of the binding portion BOa to the reading surface 273 is measured. Can be.

The contraction of the image in the sub-scanning direction F is shown in FIG.
As shown in FIG.
Based on the original surface depth h up to 73, the original length: Δi ² = ΔX ² + Δh ² (3) from the amount of change Δh in the original depth for each reading interval ΔX in the sub-scanning direction F. Thus, the contraction of the image can be restored (see FIGS. 4 and 5).

As described above, according to the present embodiment, the original surfaces of the left and right pages of the two-page spread original BO placed at a predetermined position on the original platen 1 by the holding means form the reading surface 273. By holding the two-page spread original BO and pressing the original surfaces of the left and right pages against the contact glass 104, the original surfaces of the left and right pages, which are the subjects, and the lens 1
06 and the CCD sensor 101 can be set accurately. Since the positional relationship between the document surfaces of the left and right pages and the lens 106 and the CCD sensor 101 is accurately set, the document surface depth h of the binding portion BOa can be accurately measured from the reference surface of the reading surface 273. it can.

Next, the image density correction of the binding portion BOa of the book BO will be described with reference to FIG. Book BO
Of the regular reading surface 2 as described above.
As the position becomes farther than the position 73, the illuminance of the original surface decreases due to the inclination of the original surface, and the output of the CCD sensor 101 decreases. Further, since the shape of the binding portion varies widely depending on the book original such as the binding method and the thickness of the book, the illuminance change of the document surface is also various and the image density is changed. In this embodiment, since the document depth h of the binding portion BOa is accurately measured by the above method, the image density correction is performed as follows based on the data of the document surface depth h.

That is, when performing image density correction, a density correction coefficient K, which will be described later, is multiplied by the output of the CCD sensor 101 to correct the density of the binding portion BOa of the book BO. The density correction coefficient K is set as a reference table for density correction by experiment or the like in advance corresponding to the document surface depth data and the document surface inclination data in FIG.
Using the correction coefficient α obtained from the document surface depth table 1 and the correction coefficient β obtained from the document surface inclination table 2 shown in FIG. The original surface inclination θ at this time is θ = tan based on the original surface depth h.
^-1 ΔX / Δh (5)

From the document surface depth table 1 shown in FIG. 6A, as the document surface depth h increases, the correction coefficient α becomes smaller than 1, and the document surface inclination table 2 shown in FIG. It can be seen that the correction coefficient β is inversely smaller than 1 as the original surface inclination θ approaches 90 ° and becomes larger, in other words, as the original surface inclination θ becomes steeper. Therefore, the correction coefficient α decreases as the document surface depth h increases, and the correction coefficient β decreases as the document surface inclination θ becomes steeper. Under these conditions, the product (αβ) of the correction coefficients α and β is It can be seen that the density correction coefficient K becomes even smaller than 1, and finally the density correction coefficient K becomes larger than at least 1. This is due to the fact that the fluorescent lamp driving method of the present embodiment for the reading surface 273 of the book BO employs the method of keeping the illuminance constant as described above, and the binding section BOa of the book BO has a deeper document surface. It is easily understood that the empirical rule that the illuminance of the document surface becomes darker as the document surface becomes steeper, indeed.

As described above, according to this embodiment, when performing the image density correction, the two factors of the document surface depth h and the document surface inclination θ are separated, and the respective correction coefficients α and β are selected. Therefore, it is possible to perform accurate density correction for variously different binding portion shapes.

To supplement the image density correction, when shading correction is performed, the gain value is adjusted by one to adjust the variation between the pixels of the CCD sensor 101 and the output level of the CCD sensor 101 when reading the reference white plate. Decide. With the gain value fixed, the entire image of the book BO having a constant illuminance on the document surface is read, and the gain value is changed for each scanning line from the shape of the binding portion BOa of the book BO to change the image of the book BO. Should be read.

Next, with reference to FIGS. 7 and 8, an image processing system and an image processing flow for performing image processing related to image distortion and density correction of the binding portion BOa of the book BO will be described. The control configuration shown in the figure performs image processing related to image distortion and density correction of the binding portion BOa of the book document BO, and also performs processing of normal image data output from the CCD sensor 101 as an image sensor. However, in order to clarify the features of the present invention, the former will be mainly described in detail.

In FIG. 7, reference numeral 170 denotes an image processing unit in the present invention, and reference numeral 173 denotes book original shape recognizing means. The image processing unit 170 has a control function as an image distortion processing unit that corrects image distortion of the binding portion BOa in the book document BO by image processing and a control configuration described later.

The image processing section 170 holds the original book BO, which is placed at the predetermined position on each of the original tables 1 by the holding means, on the reading surface 273 while the original book BO is being opened. Document shape recognizing means 173 for recognizing and measuring the binding portion shape of the document, and document face depth data and document face tilt data which are document face distance data recognized and measured by the book document shape recognizing means 173 are stored. Memory 175 as an image correction data storage means for performing the correction, and a document surface depth table 1 which is a numerical value table for correction preset corresponding to the document surface depth data and the document surface tilt data, respectively. And document surface tilt table 2
And a correction table memory 177 as a correction numerical value table storage means for storing the document surface depth data, the document surface inclination data, the document surface depth table, and the document surface inclination table. It mainly comprises an image correcting means 180 for correcting the image distortion of the binding portion BOa in the book BO from the obtained image correction data by image expansion processing.

The original document shape recognizing means 173 is based on a digital image signal input from the CCD sensor 101 via an A / D converter (not shown) as described with reference to FIGS. The position of the image forming pixel b on the CCD sensor 101 at the lower end of the book BO and the document set line 1S
The number of pixels d between the pixel a set in advance as a reference pixel position corresponding to the pixel number a is counted, and the document surface depth h from the document surface of the binding portion BOa to the reading surface 273 and the document surface inclination θ are measured. By doing so, it has a function of recognizing the shape of the binding portion BOa.

The image processing section 170 has a control function and a control structure as the above-described image distortion processing means, and further includes a binding section BOa based on the shape of the binding section BOa recognized and measured by the book original shape recognition section 173. It also has a control function and a configuration as image density processing means for correcting the image density of the BOa.

By the way, the image processing section 170 as the image density processing means is provided with the above-mentioned original document shape recognition means 173.
And an image correction memory 175 described above, and a density correction set from a document surface depth table 1 and a document surface tilt table 2 corresponding to document surface depth data and document surface inclination data, respectively. And a correction table memory 177 as a reference table storage means for storing a reference table, and a calculation based on the original surface depth data, the original surface inclination data, and the reference table. And an image correcting means 180 as an image density correcting means for correcting the image density of the binding portion BOa from the illuminance correction data.

The image processing section 170 includes a CPU (Central Processing Unit), an I / O (input / output) port (not shown), and an RO
It comprises a microcomputer having an M (read only storage device), a RAM (read / write storage device), and the like, which are connected by a signal bus (not shown). The image correction means 180 has a configuration corresponding to the CPU, the image correction memory 175 has a configuration corresponding to the RAM, and the correction table memory 177 has a configuration corresponding to the ROM. The image correction unit 180 transmits and receives a command signal and the various data signals described above between the image correction memory 175 and the correction table memory 177, and executes necessary control and the above-described calculations. Further, the image correcting means 180
Are respectively connected to a buffer memory 183 and a frame memory 185 as external storage devices, and transmit and receive a command signal and corrected image data, which will be described later, between the buffer memory 183 and the frame memory 185. Control. Image correction memory 17
Reference numeral 5 stores original surface depth data, original surface inclination data, illuminance correction data, and original end position data as needed. The correction table memory 177 stores data such as a document surface depth table 1, a document surface tilt table 2, a reference table, and the like.
A program for performing an image processing operation flow described later is stored in advance.

The buffer memory 183 is composed of a RAM, and has a function of temporarily storing the corrected image data subjected to the image density correction processing and the image expansion processing by the image processing section 170. The buffer memory 183 has a storage capacity for storing image data for several tens of main scanning lines read by the CCD sensor 101 in this embodiment, for example. The frame memory 185 is formed of a DRAM, and cuts unnecessary image data of the document table 1 and the like other than the original document BO, or the frame memory 185.
5 has a function of outputting the final corrected image data in which unnecessary image data has been cut in the previous stage to an image forming apparatus such as an electrophotographic copying machine or a computer as needed. In this embodiment, the frame memory 185 has a storage capacity for storing at least one page of image data of the document size A3.

Next, the image processing operation flow of the binding portion BOa in the book BO will be described with reference to FIG. First, when a reading start key (not shown) is pressed, the scanning unit 100 and the second carriage 122 travel and scan in the sub-scanning direction F, and the CCD sensor 101 starts imaging from the facing end of the book BO. An analog image signal of the book BO output from the CCD sensor 101 is converted into a digital image signal by an A / D converter (not shown), and the book document shape recognizing unit 173 of the image processing unit 170 is converted.
Is input to Then, the shape of the binding portion BOa in the book BO is measured and recognized by the book document shape recognition means 173. That is, the CCD sensor 101 is activated,
At the time of one scanning line imaging, the original set line 1 of the original platen 1
The number of pixels d between the position of the pixel a at the reference pixel position of the CCD sensor 101 corresponding to S and the position of the image forming pixel b at which the lower end of the book BO is projected is counted, and the document of the binding portion BOa is counted. The surface depth h is measured. The document surface inclination θ is obtained by comparing with the document surface depth h one scanning line before. The shape measurement of the binding portion BOa by measuring the document surface depth h and the document surface inclination θ of the binding portion BOa performed by the book document shape recognizing means 173 is performed in real time every time one scan line is imaged. Will be

Next, the image correcting means 180 generates an image from the document surface depth data, the document surface tilt data and the illuminance correction data obtained as described above based on the document surface depth h and the document surface inclination θ. Density correction data and image expansion processing data in the main and sub scanning directions are created. Then, the image correction means 1
At 80, after performing the density correction processing using the image density correction data and the image expansion processing data in the main and sub scanning directions, the image expansion processing is performed, and the corrected image data is written to the buffer memory 183.

At this time, as the image expansion processing in the sub-scanning direction F, a method of adding the image data of the previous line a plurality of times or a method of generating image data interpolated from the image data of the previous line and the current image data. And any other method may be used. Further, in order to expand the image in the sub-scanning direction F, to read the image at a constant speed and store the image data in the frame memory 185 at a constant speed, it is necessary to write the corrected data to the buffer memory 183 once. . After storing the corrected image data in the frame memory 185, the image is read out based on the document end position data of the lower end of the book BO, and is output to an image forming apparatus, a computer, or the like.

According to the above-described embodiment, with the above-described configuration and operation, a reading range to be subjected to image processing is specified by calculating an error from a specified position of the reading surface 273, and the image data calculated by the above-described error calculation is determined. It is possible to provide an image reading device that corrects image information based on the original and enables correct image reproduction. In addition, a reading range to be corrected for the light amount is specified by calculating an error from the position of the specified reading surface 273, and the image density is corrected based on the image data calculated by the above-described error calculation, so that correct image reproduction can be performed. The image reading device described above can be provided. Further, by performing the reading process of the image of the book BO and the image density correction and the image decompression process in real time for each scanning line, there is an advantage that the reading speed can be increased and the entire reading time can be reduced.

Next, a modification of the above embodiment will be described.

This modified example is different from the above-described embodiment in that the lower ends of the left and right pages of the two-page spread original BO are placed and set on each original table 1 with the lower ends of the right and left pages aligned with the original set lines 1S. As shown in FIG. 10, the only difference is that a control configuration that enables more accurate image density correction and image expansion processing in consideration of the skew when a skew occurs.

As shown in FIG. 9 and FIG. 10, when placing and setting on each original table 1 with the lower ends of the left and right pages of the two-page spread original BO aligned with the original set lines 1S, respectively.
The lower ends of the left and right pages of the spread original BO intended to be securely set are slightly displaced from the original set line 1S, or the right and left pages become "C" due to the spread of the original BO. There is a case where the BO is placed and set in a state of being skewed diagonally. When the document surface depth is measured from the contour projected on the CCD sensor 101 for the book BO placed and set in such a skew state as described above, it is the document reference position. When the amount of shrinkage is measured based on the difference between the image height fixed to the original set line 1S and the boundary of the outline, even when the original surface of the original BO is in close contact with the reading surface 273 (not shown), the above ( Equation (1) indicates that there is a document surface depth. Also, the error of the actual depth of the binding portion BOa becomes large, and the magnification differs when the image is expanded.

As described above, when measuring the document surface depth of the binding portion BOa of the book document BO, the reference image height is set for each scanning line, and the distance from the set image height to the document contour is determined. The amount of shrinkage must be measured. At this time, the method of setting the reference image height serving as a reference is such that the original document BO in the area where the original surface of the original BO is in close contact with the reading surface
(In this modified example, specifically, the position of the contour of the lower end of the book BO). Further, since the contour shape of this region is a straight line, the reference image height of the binding portion correction region is set by extending the straight line. Furthermore, by setting the straight line that becomes the reference image height independently for the left and right pages,
Even when the original BO is skewed, for example, when the original BO is set in a “C” shape due to the widening of the original BO, an accurate document surface depth can be measured. In this modification, as described above, the maximum thickness of the
mm, the center of each platen 1 is 100 mm
A skew detection area for detecting the reference image height (skew amount) of the left and right pages on the outer side. In addition, the minimum size book manuscript B
Since O is a B6 plate, 12 mm from the center of each platen 1
A skew detection area for detecting the reference image height (skew amount) of the left and right pages within 8 mm.

As described above, the reference pixel a of the CCD sensor 101 corresponding to the reference image height set for each scanning line
And the number d of pixels between the pixel b on which the lower end of the book BO is projected and the contraction amount c is obtained in the same manner as in the above embodiment using the equation (2) of the above embodiment. be able to. Then, from the relationship between the contraction amount c of the document boundary obtained by the formula (2) and the above formula (1), it is possible to measure the document surface depth h from the document surface of the binding portion BOa to the reading surface 273. it can. Also, the shrinkage of the image in the sub-scanning direction F
The above equation (3), which is a relational expression representing a change amount Δh of the document depth for each reading interval ΔX in the sub-scanning direction F based on the document surface depth h from the document surface of the binding portion BOa to the reading surface 273. , The contraction of the image can be restored.

As described above, according to the present modification, the document surfaces of the left and right pages of the two-page spread original BO placed at a predetermined position on the original platen 1 by the holding means form the reading surface 273. By holding the two-page spread original BO and pressing the original surfaces of the left and right pages against the contact glass 104, the original surfaces of the left and right pages, which are subjects, and the lens 1
06 and the CCD sensor 101 can be set accurately. When measuring the document surface depth, a reference image height is set for each scanning line, and the amount of shrinkage is measured as the distance from the set image height to the document contour. The document surface depth h of the binding portion BOa can be accurately measured from the reference surface, and the image can be accurately extended.

As for the image density correction of the binding portion BOa of the book BO, since the document depth h of the binding portion BOa is accurately measured by the above method, the data of the document surface depth h is used. Image density correction can be performed in the same manner as in the first embodiment.

Description will be made focusing on a point that the control configuration shown in FIG. 7 has a functional configuration different from that of the above embodiment. Book Original Shape Recognition Means 1 of Image Processing Unit 170 in Modification Example
Reference numeral 73 denotes a book based on a digital image signal input from the CCD sensor 101 via an A / D converter (not shown) to the book document shape recognition means 173 of the image processing unit 170 in the above embodiment. CCD at the bottom of document BO
The skew amount of each of the left and right pages is obtained from the position of the image forming pixel on the sensor 101, and a pixel a as a reference pixel position corresponding to the original set line 1S obtained by subtracting these skew amounts and a CCD sensor at the lower end of the book BO. The number d of pixels between the image forming pixel 101 and the image forming pixel 101 is counted, and the document surface depth h from the document surface of the binding portion BOa to the reading surface 273 and the document surface inclination θ are measured. The difference is that it has a function of recognizing the shape of the BOa.

Next, an image processing operation flow according to this modification will be described with reference to FIG. First, when a reading start key (not shown) is pressed, the scanning unit 100 and the second carriage 122 travel and scan in the sub-scanning direction F.
An image is started from the spread edge of the book BO by the CD sensor 101, and an analog image signal of the book BO output from the CCD sensor 101 is converted into a digital image signal by an A / D converter (not shown). , Image processing unit 170
Of the original document shape recognition means 173. Then, the shape of the binding portion BOa in the book BO is measured and recognized by the book document shape recognition means 173.

At this time, the number of pixels between the position of the reference pixel a of the CCD sensor 101 corresponding to the reference image height set for each scanning line and the position of the imaging pixel b on which the lower end of the book BO is projected By counting d, the document surface depth h of the binding portion BOa is measured. The original surface inclination θ is obtained by comparing with the original surface depth h one scanning line before. The shape measurement of the binding portion BOa by measuring the document surface depth h and the document surface inclination θ of the binding portion BOa performed by the book document shape recognizing means 173 is performed in real time every time one scan line is imaged. Will be

Next, the image correcting means 180 generates an image from the original surface depth data, the original surface inclination data, and the illuminance correction data obtained as described above based on the original surface depth h and the original surface inclination θ. Density correction data and image expansion processing data in the main and sub scanning directions are created. Then, the image correction means 1
At 80, after performing the density correction processing using the image density correction data and the image expansion processing data in the main and sub scanning directions, the image expansion processing is performed, and the corrected image data is written to the buffer memory 183.

At this time, the image expansion processing in the sub-scanning direction F can be performed by adding the image data of the previous line a plurality of times or by interpolating the image data of the previous line and the current image data, as in the above embodiment. For example, there is a method of creating the image data, and any method may be used. Further, in order to expand the image in the sub-scanning direction F, to read the image at a constant speed and store the image data in the frame memory 185 at a constant speed, it is necessary to write the corrected data to the buffer memory 183 once. . After storing the corrected image data in the frame memory 185, the image is read out based on the document end position data of the lower end of the book BO, and is output to an image forming apparatus, a computer, or the like.

According to the above modification, the inclination (skew amount) of the placed book original BO is calculated by calculating the error from the specified reading surface position 273 by the above configuration and operation, and the skew is calculated. After removing the error data caused by the skew, the reading range to be subjected to the image processing is specified, and the image information is corrected based on the image data calculated by the calculation in which the error data due to the skew is removed, thereby enabling a correct image reproduction. An image reading device can be provided. Further, by performing the reading process of the image of the book BO and the image density correction and the image decompression process in real time for each scanning line, there is an advantage that the reading speed can be increased and the entire reading time can be reduced.

As described above, the present invention has been described with respect to the specific embodiments and examples of the present invention. However, the configuration of the present invention is limited to the above-described embodiments, examples and modifications. Instead, these may be appropriately combined and configured. Within the scope of the present invention, it is possible to configure various embodiments and examples of the invention according to the necessity, purpose, application, and the like. It will be clear to those skilled in the art.

[0155]

As described above, according to the present invention, it is possible to solve the above-mentioned conventional problems and to improve the image reading speed of a book original, and to improve the image reading and image processing as a whole. The time can be shortened, the memory amount can be reduced as much as possible, and the cost and the size of the mechanical device can be reduced.

The effects of each claim are as follows. According to the first to third and fifth aspects of the invention,
Image reading that specifies the reading range to be subjected to image processing by error calculation from a specified reading surface position, corrects image distortion based on the image data calculated by the error calculation, and enables correct image reproduction An apparatus can be provided.

According to the seventh to ninth and eleventh aspects of the present invention, a reading range to be corrected in light amount is specified by calculating an error from a specified reading surface position, and the image data calculated by the error calculation is also used. Thus, it is possible to provide an image reading device that corrects the image density and reproduces the image correctly.

According to the sixth and twelfth aspects of the present invention,
In addition to the effects of the above inventions, it is possible to provide an image reading apparatus that can perform a reading process of an image of a book document and an image process in real time to increase a reading speed.

According to the fourth and tenth aspects of the present invention,
In addition to the effects of the above inventions, the amount of skew (skew amount) of a placed book original is calculated by calculating an error from a specified reading surface position, and error data due to the skew is removed. Provided is an image reading apparatus that specifies a reading range to be processed, corrects image distortion and image density based on image data calculated by a calculation in which error data due to the skew is removed, and enables correct image reproduction. be able to.

[Brief description of the drawings]

FIG. 1 is a schematic side view illustrating a principle of measuring a document surface depth of a binding portion of a book document.

FIG. 2A is a plan view of a main part showing a state in which a double-page spread original is placed and set on an original platen, and FIG.
FIG. 2 is a longitudinal sectional view of FIG.

FIG. 3 is a schematic side view in which main parts for supplementing the principle of FIG. 1 are enlarged.

FIG. 4 is a plan view of a main part showing a state in which a document surface at a lower end portion of a binding portion of a two-page spread document is contracted in the main scanning direction.

FIG. 5 is a front view of a main part showing a document surface depth, a document surface length, and a document surface inclination of a binding portion of a two-page spread document;

FIG. 6A is an example of a document surface depth table used for image density correction of a binding portion of a two-page spread document;
FIG. 3B is a diagram illustrating an example of a document surface tilt table used for the image density correction.

FIG. 7 is a control block diagram illustrating an image processing system of the image reading apparatus.

FIG. 8 is a flowchart illustrating a schematic image processing flow of the image reading apparatus.

FIG. 9 is a diagram showing a state in which a two-page spread original is placed and set on a platen in a state where a skew has occurred, and is a plan view of a main portion illustrating the setting of a skew detection area.

FIG. 10 is an enlarged plan view of a main part of FIG. 9;

FIG. 11 is a cross-sectional view illustrating an overall configuration of an image reading apparatus to which the present invention has been applied.

FIG. 12 is a cross-sectional view illustrating a configuration of a scanning unit in the image reading device.

FIG. 13 is a schematic side view of a document table unit in the image reading apparatus.

FIG. 14 is a schematic plan view of a document table in the image reading apparatus.

FIG. 15 is a schematic plan view of a document table unit in the image reading apparatus.

FIG. 16 is a schematic perspective view of a size stopper that positions the left and right document tables in the document table unit according to the size of a book document.

FIG. 17 is a schematic plan view of the size stopper.

FIG. 18 is a schematic perspective view of a unit opening / closing lock mechanism for opening and closing a scanner unit with respect to a document table unit of the image reading apparatus.

FIG. 19 is a side view of the unit opening / closing lock mechanism.

FIG. 20 is a perspective view of a platen pressure fixing switching device in the platen unit.

FIG. 21 is a schematic sectional view of the platen pressure fixing switching device.

FIG. 22 is a perspective view of one component of the document table pressing / fixing switching device.

FIG. 23 is a schematic perspective view of a drive section of the platen pressure fixing switching device.

FIG. 24 is a schematic plan view of the platen pressure fixing switching device.

FIG. 25 is a schematic side view of the image reading apparatus at the time of a downward retract operation of a document table.

FIG. 26 is a timing chart at the time of a retracting operation of the original table under the image reading apparatus.

FIG. 27 is a transition diagram at the home position of the scanning unit in the pressing / fixing operation mode of the document table.

FIG. 28 is a transition diagram at an image reading start position of the scanning unit in the pressing / fixing operation mode of the document table.

FIG. 29 is a transition diagram at the book document center point of the scanning unit in the pressing and fixing operation mode of the document table.

FIG. 30 is a transition diagram when the scanning unit is reading an image on the right page of the book or turning up the right page in the pressing / fixing operation mode of the document table.

FIG. 31 is a transition diagram at the image reading completion position or the page turning start position of the scanning unit in the pressing / fixing operation mode of the document table.

FIG. 32 is an operation timing chart of the scanner motor and the right and left platen elevating motors in the pressing and fixing operation mode of the platen.

FIG. 33 is a schematic plan view showing a drive transmission system of a first carriage, a second carriage, and a belt carriage.

FIG. 34 is a schematic perspective view showing a second drive transmission system for driving a first carriage and a second carriage.

FIG. 35 is a perspective view showing a state in which drive wires are routed in a second drive transmission system.

FIG. 37 is a schematic sectional view showing a structure of a sheet winding roller of a belt carriage in the scanning unit.

FIG. 38 is a schematic side view showing a driving mechanism of a sheet winding roller and a turning roller of a belt carriage in the scanning unit.

FIG. 39 is a schematic sectional view showing a positional relationship between a document pressing roller of an image reading unit and a contact glass in the scanning unit.

FIG. 40 is a schematic sectional view showing a positional relationship between a contact glass and a glass holder of an image reading unit of a first carriage in the scanning unit.

FIG. 41 is a schematic sectional view of a main part showing a page turning operation of a belt carriage in the scanning unit.

FIG. 42 is a transition diagram at a left page image reading position in a page turning operation mode of the belt carriage in the scanning unit.

FIG. 43 is a transition diagram at a right page image reading completion position in a page turning operation mode of the belt carriage in the scanning unit.

FIG. 44 is a transition diagram at a right page turning start position in a page turning operation mode of the belt carriage in the scanning unit.

FIG. 45 is a transition diagram in the middle of turning the right page in the page turning operation mode of the belt carriage in the scanning unit.

FIG. 46 is a transition diagram at a right page turning end position in a page turning operation mode of the belt carriage in the scanning unit.

FIG. 47 is a transition diagram in the middle of discharging the right page in the page turning operation mode of the belt carriage in the scanning unit.

FIG. 48 is an explanatory diagram of an image reading portion and a timing of charging the turning belt at a position where the right page image reading is completed by the scanning unit in a page turning operation mode of the belt carriage in the scanning unit.

FIG. 49 is a schematic perspective view for explaining a positional relationship between a turning belt of a belt carriage and a page feed roller in the scanning unit.

FIG. 50 is a schematic side view showing a contact state of a page feed roller with a turning belt of a belt carriage in the scanning unit.

FIG. 51 is a schematic side view showing a state in which the page feed roller is retracted from the turn belt by a toggle joint device that drives the page feed roller in conjunction with the operation of the turn belt of the belt carriage in the scanning unit. .

FIG. 52 is a schematic side view showing a state where the page feed roller is brought into contact with the turning belt by the toggle joint device.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 Document table as document table 1S Document set line as document reference position 5 Upper and lower table 6 Base 7a, 7b, 8, 9, 16 Angle 10 Link plate 11 Link arm 12 Stud 13 Torsion spring 14 Back support plate 17 Tension spring REFERENCE SIGNS LIST 30 scanner unit 35 platen unit 40 control wire 41, 42, 44 hook 43 tension spring 45 stop ball 46, 47 pulley 48 control pulley 49 stop hole 50 groove 51 one-way clutch 52 sliding bearing 56, 57 gear 58 worm wheel 60 worm gear 61 Platen lifting motor 101 CCD sensor (CCD line sensor) as an image sensor constituting image reading means 100 Scanning unit 104 Contact glass constituting holding means 105 Fluorescent lamp 106 Image reading means Lens 108 constituting the image optical system 108 First mirror constituting the image forming optical system of the image reading means 110 Second mirror 111 constituting the image forming optical system of the image reading means 111 Second constituting the image forming optical system of the image reading means 3 mirror 121 First carriage 122 constituting a scanning unit 122 Second carriage 123 Belt carriage constituting a scanning unit 143 Scanner motor 170 Image processing unit as image distortion processing means and image density correction means 173 Book original shape recognition means 175 Image correction Correction memory 177 as correction data table storage means 180 Image correction means 208 also serving as image density correction means Turnover belt 273 Reading surface 281a, 281b Document holding roller constituting holding means 28 a, 282b Document holding sheet constituting the holding means BO Book original BOa Binding section of book original F Sub-scanning direction K Density correction coefficient S Main scanning direction h Document surface depth as document surface distance c Document at binding section of book original Amount of contraction of image on main surface in main scanning direction θ Original surface inclination

[Procedure amendment]

[Submission date] April 30, 1997

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Brief description of drawings

[Correction method] Change

[Correction contents]

[Brief description of the drawings]

FIG. 1 is a schematic side view illustrating a principle of measuring a document surface depth of a binding portion of a book document.

FIG. 2A is a plan view of a main part showing a state in which a double-page spread original is placed and set on an original platen, and FIG.
FIG. 2 is a longitudinal sectional view of FIG.

FIG. 3 is a schematic side view in which main parts for supplementing the principle of FIG. 1 are enlarged.

FIG. 4 is a plan view of a main part showing a state in which a document surface at a lower end portion of a binding portion of a two-page spread document is contracted in the main scanning direction.

FIG. 5 is a front view of a main part showing a document surface depth, a document surface length, and a document surface inclination of a binding portion of a two-page spread document;

FIG. 6A is an example of a document surface depth table used for image density correction of a binding portion of a two-page spread document;
FIG. 3B is a diagram illustrating an example of a document surface tilt table used for the image density correction.

FIG. 7 is a control block diagram illustrating an image processing system of the image reading apparatus.

FIG. 8 is a flowchart illustrating a schematic image processing flow of the image reading apparatus.

FIG. 9 is a diagram showing a state in which a two-page spread original is placed and set on a platen in a state where a skew has occurred, and is a plan view of a main portion illustrating the setting of a skew detection area.

FIG. 10 is an enlarged plan view of a main part of FIG. 9;

FIG. 11 is a cross-sectional view illustrating an overall configuration of an image reading apparatus to which the present invention has been applied.

FIG. 12 is a cross-sectional view illustrating a configuration of a scanning unit in the image reading device.

FIG. 13 is a schematic side view of a document table unit in the image reading apparatus.

FIG. 14 is a schematic plan view of a document table in the image reading apparatus.

FIG. 15 is a schematic plan view of a document table unit in the image reading apparatus.

FIG. 16 is a schematic perspective view of a size stopper that positions the left and right document tables in the document table unit according to the size of a book document.

FIG. 17 is a schematic plan view of the size stopper.

FIG. 18 is a schematic perspective view of a unit opening / closing lock mechanism for opening and closing a scanner unit with respect to a document table unit of the image reading apparatus.

FIG. 19 is a side view of the unit opening / closing lock mechanism.

FIG. 20 is a perspective view of a platen pressure fixing switching device in the platen unit.

FIG. 21 is a schematic sectional view of the platen pressure fixing switching device.

FIG. 22 is a perspective view of one component of the document table pressing / fixing switching device.

FIG. 23 is a schematic perspective view of a drive section of the platen pressure fixing switching device.

FIG. 24 is a schematic plan view of the platen pressure fixing switching device.

FIG. 25 is a schematic side view of the image reading apparatus at the time of a downward retract operation of a document table.

FIG. 26 is a timing chart at the time of a retracting operation of the original table under the image reading apparatus.

FIG. 27 is a transition diagram at the home position of the scanning unit in the pressing / fixing operation mode of the document table.

FIG. 28 is a transition diagram at an image reading start position of the scanning unit in the pressing / fixing operation mode of the document table.

FIG. 29 is a transition diagram at the book document center point of the scanning unit in the pressing and fixing operation mode of the document table.

FIG. 30 is a transition diagram when the scanning unit is reading an image on the right page of the book or turning up the right page in the pressing / fixing operation mode of the document table.

FIG. 31 is a transition diagram at the image reading completion position or the page turning start position of the scanning unit in the pressing / fixing operation mode of the document table.

FIG. 32 is an operation timing chart of the scanner motor and the right and left platen elevating motors in the pressing and fixing operation mode of the platen.

FIG. 33 is a schematic plan view showing a drive transmission system of a first carriage, a second carriage, and a belt carriage.

FIG. 34 is a schematic perspective view showing a second drive transmission system for driving a first carriage and a second carriage.

FIG. 35 is a perspective view showing a state in which drive wires are routed in a second drive transmission system.

FIG. 36 is a schematic side view illustrating operations of a first carriage, a second carriage, and a belt carriage.

FIG. 37 is a schematic sectional view showing a structure of a sheet winding roller of a belt carriage in the scanning unit.

FIG. 38 is a schematic side view showing a driving mechanism of a sheet winding roller and a turning roller of a belt carriage in the scanning unit.

FIG. 39 is a schematic sectional view showing a positional relationship between a document pressing roller of an image reading unit and a contact glass in the scanning unit.

FIG. 40 is a schematic sectional view showing a positional relationship between a contact glass and a glass holder of an image reading unit of a first carriage in the scanning unit.

FIG. 41 is a schematic sectional view of a main part showing a page turning operation of a belt carriage in the scanning unit.

FIG. 42 is a transition diagram at a left page image reading position in a page turning operation mode of the belt carriage in the scanning unit.

FIG. 43 is a transition diagram at a right page image reading completion position in a page turning operation mode of the belt carriage in the scanning unit.

FIG. 44 is a transition diagram at a right page turning start position in a page turning operation mode of the belt carriage in the scanning unit.

FIG. 45 is a transition diagram in the middle of turning the right page in the page turning operation mode of the belt carriage in the scanning unit.

FIG. 46 is a transition diagram at a right page turning end position in a page turning operation mode of the belt carriage in the scanning unit.

FIG. 47 is a transition diagram in the middle of discharging the right page in the page turning operation mode of the belt carriage in the scanning unit.

FIG. 48 is an explanatory diagram of an image reading portion and a timing of charging the turning belt at a position where the right page image reading is completed by the scanning unit in a page turning operation mode of the belt carriage in the scanning unit.

FIG. 49 is a schematic perspective view for explaining a positional relationship between a turning belt of a belt carriage and a page feed roller in the scanning unit.

FIG. 50 is a schematic side view showing a contact state of a page feed roller with a turning belt of a belt carriage in the scanning unit.

FIG. 51 is a schematic side view showing a state in which the page feed roller is retracted from the turn belt by a toggle joint device that drives the page feed roller in conjunction with the operation of the turn belt of the belt carriage in the scanning unit. .

FIG. 52 is a schematic side view showing a state where the page feed roller is brought into contact with the turning belt by the toggle joint device.

[Description of Signs] 1 Document table as document table 1S Document set line as document reference position 5 Upper and lower tables 6 Base 7a, 7b, 8, 9, 16 Angle 10 Link plate 11 Link arm 12 Stud 13 Torsion spring 14 Back Support plate 17 Tension spring 30 Scanner unit 35 Document table unit 40 Control wire 41, 42, 44 Hook 43 Tension spring 45 Stop ball 46, 47 Pulley 48 Control pulley 49 Stop hole 50 Groove 51 One-way clutch 52 Sliding bearing 56, 57 Gear 58 Worm wheel 60 Worm gear 61 Original table elevating motor 101 CCD sensor (CCD line sensor) as an image pickup device constituting image reading means 100 Scanning unit 104 Contact glass constituting holding means 105 Fluorescent lamp 106 Image Lens 108 constituting the image forming optical system of the reading means 108 First mirror 110 constituting the image forming optical system of the image reading means 110 Second mirror 111 constituting the image forming optical system of the image reading means 111 Image forming optical system of the image reading means 121 The first carriage 122 which constitutes the scanning unit 122 The second carriage 123 The belt carriage which constitutes the scanning unit 143 The scanner motor 170 The image processing unit as the image distortion processing means and the image density correction means 173 The original document shape recognition Means 175 Image correction memory as image correction data storage means 177 Correction table memory as correction numerical value table storage means 180 Image correction means also serving as image density correction means 208 Turnover belt 273 Reading surface 281a, 281b Construct holding means Manuscript Document holding sheet BO constituting the holding means BO Book manuscript BOa Book manuscript binding section F Sub-scanning direction K Density correction coefficient S Main scanning direction h Document surface depth as document plane distance c Book binding part of book manuscript Amount of shrinkage of image in main scanning direction on original surface θ Original surface inclination

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI G06T 3/00 G06F 15/62 380 H04N 1/04 106 15/66 360 1/10 H04N 1/10 1/107

Claims (12)

[Claims] 1. A book mounting table for mounting a book at a predetermined position, and a reading surface having substantially the same plane as an image surface of the double-page spread document placed at the predetermined position on the book mounting table. Holding means for holding the image, and an image arranged at a predetermined distance from the reading surface in order to read the image surface of the double-page spread original placed at the predetermined position on the book original mounting table. Reading means for recognizing the binding portion shape of the spread original while holding the image surface of the spread original placed at the predetermined position on the book original mounting table by the holding means on the reading surface; Image reading means for correcting the image distortion of the binding portion from the binding portion shape recognized by the book document shape recognizing means. apparatus. 2. The image reading apparatus according to claim 1, wherein said image reading means includes an image pickup device for reading an image of a two-page spread original placed at said predetermined position on said book placement table. An image reading device comprising an image optical system. 3. The image reading apparatus according to claim 2, wherein the predetermined position on the book mounting table is a document reference position for positioning by contacting one of upper and lower ends of the book. The image pickup device comprises a CCD line sensor, and the book document shape recognizing means is provided at the end of the book document.
The number of pixels between the position of the image forming pixel on the D-line sensor and the reference pixel position corresponding to the document reference position is counted, and the document surface distance from the document surface of the binding portion to the reading surface and the document surface are counted. An image reading apparatus characterized by recognizing the binding portion shape by measuring the inclination. 4. The image reading apparatus according to claim 2, wherein the predetermined position on the book mounting table is a document reference position which is positioned by contacting one of upper and lower ends of the book. The image pickup device comprises a CCD line sensor, and the book document shape recognizing means is provided at the end of the book document.
The skew amount of each of the left and right pages is obtained from the position of the image forming pixel on the D line sensor. An image reading device for recognizing the binding portion shape by counting the number of pixels between the two and measuring the document surface distance from the document surface of the binding portion to the reading surface and the document surface inclination. . 5. An image reading apparatus according to claim 3, wherein said image distortion processing means comprises an image correction means for storing original surface distance data and original surface inclination data measured by said original original shape recognizing means. Data storage means, correction value table storage means for storing a correction value table preset corresponding to the document surface distance data and the document surface tilt data, respectively, the document surface distance data and Image correction means for performing a calculation based on the document surface inclination data and each of the correction numerical tables, and correcting the image distortion of the binding portion by image expansion processing from the obtained image correction data. An image reading apparatus, wherein the image distortion of the binding section is corrected by image processing. 6. The image reading device according to claim 1, wherein the binding section shape is recognized in real time by the book document shape recognizing unit while the book document image is being read. An image reading apparatus for correcting image distortion of a part. 7. A book mounting table for mounting a book at a predetermined position, and a reading surface having substantially the same plane as an image surface of a double-page spread original placed at the predetermined position on the book mounting table. Holding means for holding the image, and an image arranged at a predetermined distance from the reading surface in order to read the image surface of the double-page spread original placed at the predetermined position on the book original mounting table. Reading means for recognizing the binding portion shape of the spread original while holding the image surface of the spread original placed at the predetermined position on the book original mounting table by the holding means on the reading surface; Image reading means for correcting the image density of the binding section from the binding section shape recognized by the book document shape recognizing section. apparatus. 8. An image reading apparatus according to claim 7, wherein said image reading means includes an image pickup device for reading an image of a two-page spread original placed at said predetermined position on said book placement table. An image reading device comprising an image optical system. 9. The image reading device according to claim 8, wherein the predetermined position on the book mounting table is a document reference position for positioning by contacting one of the upper and lower ends of the book. The image pickup device comprises a CCD line sensor, and the book document shape recognizing means is provided at the end of the book document.
The number of pixels between the position of the image forming pixel on the D-line sensor and the reference pixel position corresponding to the document reference position is counted, and the document surface distance from the document surface of the binding portion to the reading surface and the document surface are counted. An image reading apparatus characterized by recognizing the binding portion shape by measuring the inclination. 10. The image reading apparatus according to claim 8, wherein the predetermined position on the book mounting table is a document reference position for positioning by contacting one of upper and lower ends of the book. The image pickup device comprises a CCD line sensor, and the book document shape recognizing means is provided at the end of the book document.
The skew amount of each of the left and right pages is obtained from the position of the image forming pixel on the D line sensor. An image reading device for recognizing the binding portion shape by counting the number of pixels between the two and measuring the document surface distance from the document surface of the binding portion to the reading surface and the document surface inclination. . 11. An image reading apparatus according to claim 9, wherein said image density processing means includes an image correcting means for storing the document surface distance data and the document surface inclination data recognized by said book document shape recognizing means. Data storage means, reference table storage means for storing a reference table for density correction preset corresponding to the document surface distance data and the document surface tilt data, respectively, the document surface distance data and Image density correction means for performing a calculation based on the document surface tilt data and the reference table, and correcting the image density of the binding portion from the density correction data obtained by the calculation; An image reading device for correcting a density. 12. The image reading apparatus according to claim 7, wherein the binding section shape is recognized in real time by the book original shape recognizing means during reading of the book original image. An image reading apparatus for correcting the image density of a unit.