WO2010070760A1 - Image sensor unit and image reading apparatus - Google Patents

Abstract

Provided is an image sensor unit having a sensor substrate (8) whereupon a plurality of photoelectric conversion elements (7) are formed, an illuminating device (2) for applying light to an original (16), and a lens array (6) which forms an image on the photoelectric conversion element (7) by reflection light from the original. On a single frame (5), which supports the sensor substrate (8), the illuminating device (2) and the lens array (6), a first aligning section (10) for holding the illuminating device (2), a second aligning section (12) for holding the lens array (6) and a third aligning section (14) for holding the sensor substrate (8) are formed. The assembly directions of the illuminating device (2), the lens array (6) and the sensor substrate (8) to the first aligning section (10), the second aligning section (12) and the third aligning section (14) are identical to each other.

Description

Image sensor unit and image reading apparatus

The present invention relates to an image sensor unit and an image reading apparatus. In particular, the present invention relates to an image sensor unit and an image reading apparatus in which components can be assembled from the same direction.

Conventionally, image sensor units used in image reading apparatuses such as image scanners, facsimiles, and copying machines are roughly classified into the following two types.

First, there is a flat bed type in which a document is fixed on a document support table in the image reading apparatus, and the image sensor unit moves and reads.

Second, there is a sheet feed type in which the image sensor unit is fixed to the image reading apparatus and the original paper on the original support table is moved to perform reading.

Hereinafter, the configuration of a conventional image sensor unit will be described. FIG. 6 is an example of an image reading apparatus, and is a perspective view showing an appearance of a flat bed type image scanner using an image sensor unit.

In FIG. 6, reference numeral 60 denotes an image sensor unit, which is a contact image sensor unit (CIS; Contact).
Known as Image Sensor). Reference numeral 61 is a drive motor, 62 is a wire, 63 is a transparent glass document support table, and 64 is a pressure plate.

In the image scanner shown in FIG. 6, the image sensor unit 60 is moved in the reading direction (sub-scanning direction) by driving the drive motor 61 and mechanically moving the wire 62.

FIG. 7 is a cross-sectional view in the sub-scanning direction of a conventional flat bed type image scanner. This figure shows a configuration in which one illumination device extending in the main scanning direction is used.

In FIG. 7, reference numeral 70 denotes a light source unit. The light source unit 70 includes an LED 70R that emits red light, an LED 70G that emits green light, and an LED 70B that emits blue light.

Reference numeral 71 denotes an illumination device, which includes a light guide 72 and a light guide cover 73. A light source unit 70 is disposed on the end surface of the lighting device 71 in the longitudinal direction.

74 is a rod lens array, and is configured by arranging a plurality of erecting equal-magnification imaging lens elements in the main scanning direction in the direction orthogonal to the paper surface. Reference numeral 75 denotes a line-shaped sensor array including a plurality of light receiving portions (photoelectric conversion elements) that perform photoelectric conversion, and 76 denotes a sensor substrate. The sensor array 75 is mounted on the sensor substrate 76 together with the light source unit 70.

77 is a frame for supporting the constituent members. The frame 77 is provided with a first positioning portion 77A that holds the illumination device 71, a second positioning portion 77B that holds the rod lens array 74, and a third positioning portion 77C that holds the sensor substrate 76.

78 is a connector for connecting the sensor substrate 76 and an external device. Reference numeral 79 denotes a manuscript. The document 79 is placed on a document support table 63 made of transparent glass.

FIG. 8 is a cross-sectional view in the sub-scanning direction of a conventional sheet feed type image scanner. This figure shows a configuration in which two illumination devices extending in the main scanning direction are used.

In FIG. 8, reference numeral 80 denotes an image sensor unit, and 81 denotes a lighting device. Reference numeral 82 denotes a document transport roller, which transports the document 79 by rotating while sandwiching the document 79. Note that components similar to those in FIG. 7 are denoted by the same reference numerals.

In the sheet feed type image scanner shown in FIG. 8, the conveyance path is set by nipping and conveying the document 79 between the document conveyance rollers 82, and the document side focal point of the rod lens array 74 is set at the approximate center. Yes.

In the conventional flat bed type and sheet feed type image scanners described with reference to FIGS. 6 to 8, the light emitted from the light source unit in the image sensor unit 60 or 80 is guided into the illumination device and reflected. Is repeated, the sheet goes toward the document 79 at an angle of approximately 45 degrees. This light is reflected by the document 79, and an optical image of the reflected light (read image) is formed on the sensor array 75 by the rod lens array 74. Then, this optical image is photoelectrically converted into an electric signal to read image information for each line.

By the way, the conventional image sensor unit described above has a configuration in which the lighting device and the rod lens array 74 are assembled from one of the frames 77 and the sensor substrate 76 is assembled from the other of the frames 77 when each component is assembled.

That is, with reference to FIG. 7, when the contact surface between the rod lens array 74 provided on the frame 77 and the second positioning portion 77B is used as a reference surface for assembly for determining the focal position, first, Then, the rod lens array 74 is inserted from the document surface side (upper surface side) (arrow A) and brought into contact with the contact surface (or adjusted to the optimum position therefrom) to fix the position.

Next, the illumination device 71 is inserted from the document surface side (upper surface side), and is brought into contact with the contact surface of the second positioning portion 77B to fix the position.

Then, the sensor substrate 76 on which the light source unit 70 and the sensor array 75 are mounted is inserted into the third positioning portion 77C from the opposite side (back side) of the document surface (arrow B). At this time, the sensor substrate 76 is brought into contact with the contact surface opposite to the contact surface of the first positioning portion 77A, and is fixed to the focal position of the rod lens array 74. In addition, assembling of the image scanner shown in FIG.

As described above, in the conventional image scanner, the components to be mounted on the frame are assembled from two directions (or more). In this case, there has been a problem that the assembling work is complicated, for example, it is necessary to adjust the focus of the rod lens array, the number of assembling jigs increases, and the number of man-hours also increases.

In addition, since the contact surface between each component member and the frame serves as a reference for assembly, if an assembly error occurs during assembly from two directions (or more), the error is inconsistent with each assembly direction. As a result, errors are accumulated and the assembly accuracy deteriorates.

In addition, the operator needs to assemble the light source unit, rod lens array, sensor board, etc. while turning the frame upside down on the workbench, so not only the workability is bad, but also dust etc. enter the image sensor unit. There was a fear.

In order to solve these problems, Patent Document 1 and Patent Document 2 propose an image sensor unit that can be assembled from only one direction (see FIGS. 9 and 10).

However, in the structure shown in Patent Document 1, as shown in FIG. 9, the assembly of the constituent members such as the rod lens array 91, the illumination device 92, and the sensor substrate 94 on which the sensor array 93 is mounted is from the same direction. Although it becomes possible, it is necessary to use two support members (frames) (the first support member 95 and the second support member 96), and there is a problem that the number of parts increases.

In addition, since the assembly reference (contact surface) between the rod lens array 91 and the sensor substrate 94 is in both directions with respect to the first support member 95, the assembly error accumulates when an assembly error occurs in the constituent members. There was a problem to do.

Also, in the structure shown in Patent Document 2, as shown in FIG. 10, the assembly of constituent members such as the rod lens array 101, the illumination device 102, and the sensor substrate 104 on which the sensor array 103 is mounted is the same direction. Is possible.

However, the structure of Patent Document 2 also requires two frames (molded frame 105 and metal frame 106) as in Patent Document 1, and those constituent members are held down and fixed by the metal frame 106 and the cover glass 107. Therefore, there is a problem that the number of parts increases.

Further, since the cover glass 107 simultaneously suppresses the constituent members such as the rod lens array 101, the illumination device 102, and the sensor substrate 104, the cover glass 107 also serves as a support member. There is a risk that assembly errors such as tilting of the members may occur.

The present invention has been made in view of such circumstances, and in assembling the image sensor unit, by assembling the constituent members from the same direction, the workability is improved and the assembly loss is reduced, and the contact direction of the constituent members is also improved. The purpose is to improve the assembly accuracy by setting the same direction.

Japanese Patent Laid-Open No. 06-22086 Japanese Patent Laid-Open No. 08-293963

An image sensor unit of the present invention includes a sensor substrate on which a plurality of photoelectric conversion elements are mounted, an illumination device that irradiates light on a document, and a lens array that forms an image of reflected light from the document on the photoelectric conversion element. An image sensor unit comprising: a frame for holding the sensor substrate, the illumination device, and the lens array; and a first positioning unit for holding the illumination device, and the lens array being held on the frame. Forming a second positioning portion and a third positioning portion for holding the sensor substrate, and each of the first positioning portion, the second positioning portion, and the third positioning portion in the same direction. It is characterized by opening.
In another image sensor unit of the present invention, the first positioning unit, the second positioning unit, and the third positioning unit are incorporated into the illumination device, the lens array, and the sensor substrate. It is characterized by having an opening.
According to another image sensor unit of the present invention, the first positioning unit, the second positioning unit, and the third positioning unit each relate to the illumination device, the lens array, and the sensor substrate. It is provided with the latching | locking part which stops.
In another image sensor unit of the present invention, the contact direction between the lens array and the second positioning portion is the same as the contact direction between the sensor substrate and the third positioning portion. It is characterized by that.
In another image sensor unit of the present invention, the illumination device includes a light guide that guides light from the light source to the document, and the light source is arranged in parallel with the light guide and mounted on the sensor substrate. It is characterized by that.
The image reading apparatus of the present invention includes a sensor substrate on which a plurality of photoelectric conversion elements are mounted, an illumination device that irradiates light on the original, and a lens array that forms an image of reflected light from the original on the photoelectric conversion element. An image reading apparatus including an image sensor unit including: a frame that holds the sensor substrate, the illumination device, and the lens array; and a first positioning unit that holds the illumination device on the frame And a second positioning part for holding the lens array and a third positioning part for holding the sensor substrate, and the first positioning part, the second positioning part, and the third positioning part. Each of the positioning portions is opened in the same direction.
In another image reading apparatus of the present invention, the first positioning unit, the second positioning unit, and the third positioning unit are incorporated into the illumination device, the lens array, and the sensor substrate. It is characterized by having an opening.
According to another image reading apparatus of the present invention, the first positioning unit, the second positioning unit, and the third positioning unit respectively relate to the illumination device, the lens array, and the sensor substrate. It is provided with the latching | locking part stopped.
In another image reading apparatus of the present invention, the contact direction between the lens array and the second positioning portion is the same as the contact direction between the sensor substrate and the third positioning portion. It is characterized by that.
According to another image reading apparatus of the present invention, the illumination device includes a light guide that guides light from a light source to the document, and the light source is arranged in parallel with the light guide and mounted on the sensor substrate. It is characterized by that.
According to the present invention having the above-described configuration, the assembly of the image sensor unit can be remarkably simplified and the troublesome focus adjustment work can be omitted. Accuracy can be improved.
In addition, since it is not necessary for the operator to assemble the frame while turning it upside down on the workbench, it is possible to reduce the intrusion of dust and the like into the image sensor unit, and to reduce the assembly loss.

FIG. 1 is a cross-sectional view of the image sensor unit according to the first embodiment of the present invention in the sub-scanning direction. FIG. 2A is a diagram illustrating an assembly process of the image sensor unit according to the first embodiment of the present invention. FIG. 2B is a diagram illustrating an assembly process of the image sensor unit according to the first embodiment of the present invention. FIG. 2C is a diagram illustrating an assembly process of the image sensor unit according to the first embodiment of the present invention. FIG. 2D is a diagram illustrating an assembly process of the image sensor unit according to the first embodiment of the present invention. FIG. 3A is a diagram for explaining assembly accuracy by a conventional image sensor unit. FIG. 3B is a diagram illustrating an effect of improving the assembly accuracy by the image sensor unit according to the first embodiment of the present invention. FIG. 4 is a cross-sectional view in the sub-scanning direction of an image sensor unit according to the second embodiment of the present invention. FIG. 5 is a cross-sectional view in the sub-scanning direction of an image sensor unit according to another embodiment of the present invention. FIG. 6 is a perspective view showing an appearance of a flat bed type image scanner using a conventional image sensor unit. FIG. 7 is a cross-sectional view in the sub-scanning direction of a conventional flatbed image scanner. FIG. 8 is a cross-sectional view in the sub-scanning direction of a conventional sheet feed type image scanner. FIG. 9 is a perspective view showing the image sensor unit described in Patent Document 1. As shown in FIG. FIG. 10 is a cross-sectional view of the image sensor unit described in Patent Document 2 in the sub-scanning direction.

Hereinafter, embodiments to which the present invention can be applied will be described with reference to the drawings.

<First Embodiment>
FIG. 1 is a cross-sectional view in the sub-scanning direction of a contact image sensor unit (CIS) according to a first embodiment of the present invention. Such an image sensor unit is provided in an image reading apparatus such as an image scanner, a facsimile, or a copying machine.

In FIG. 1, 1 is a light source unit as a light source. The light source unit 1 includes an LED 1R that emits red light, an LED 1G that emits green light, and an LED 1B that emits blue light.

2 is an illuminating device, which is designed to irradiate light from the light source unit 1 substantially uniformly over the length of a document reading section (described later, sensor array 7). The illumination device 2 includes a light guide 3 and a light guide cover 4.

5 is a frame as a support. Reference numeral 6 denotes a rod lens array as an imaging element. Reference numeral 7 denotes a sensor array as a photoelectric conversion element. Reference numeral 8 denotes a sensor substrate on which the sensor array 7 and the light source unit 1 are mounted. That is, the image sensor unit 9 has a configuration in which the illumination device 2, the rod lens array 6, and the sensor substrate 8 are attached to the frame 5.

In the image sensor unit 9 shown in FIG. 1, the illumination device 2, the rod lens array 6, and the sensor substrate 8 are attached to a single frame 5, respectively. Positioning portions each having a locking portion are formed on the frame 5, and the lighting device 2, the rod lens array 6, and the sensor substrate 8 are pressed and locked by the elasticity of the locking portions.

That is, 10 is a first positioning portion that holds the lighting device 2, and 11 is a first locking portion formed in the first positioning portion 10.

12 is a second positioning portion that holds the rod lens array 6 in the optical axis direction, and 13 is a second locking portion formed in the second positioning portion 12.

14 holds the sensor substrate 8, the light source unit 1 mounted on the sensor substrate 8 is arranged on the end surface in the longitudinal direction of the illumination device 2, and the sensor array 7 is arranged in a predetermined direction in the optical axis direction of the rod lens array 6. It is the 3rd positioning part distribute | arranged to a focus position. Reference numeral 15 denotes a third locking portion formed in the third positioning portion 14.

Here, in the present embodiment, the first to third locking portions 11, 13, 15 are formed so as to protrude moderately inward of the openings of the first to third positioning portions 10, 12, 14, respectively. , And can be deformed and restored in the direction opposite to the protruding direction. The protruding amounts of the first to third locking portions 11, 13, 15 are set to a necessary and sufficient level for locking the illumination device 2, the rod lens array 6, and the sensor substrate 8, and these components are further incorporated. In this case, it is set to be able to get over by pushing them in. The first to third locking portions 11, 13, and 15 are preferably formed intermittently in the main scanning direction.

Further, the contact surface 12A between the rod lens array 6 and the second positioning portion 12 provided on the frame 5 is a surface serving as a reference for assembly for determining the focal position. The first to third positioning portions 10, 12, and 14 are provided to be opened in the same direction. Then, the contact surfaces 10A, 12A, and 14A of the respective positioning portions serve as assembly references. That is, the first to third positioning portions 10, 12, and 14 are opened to incorporate the component members, and these openings are oriented in the same direction, from which the component members are incorporated. By doing in this way, the assembly direction X with respect to the flame | frame 5 of the illuminating device 2, the rod lens array 6, and the sensor board | substrate 8 becomes the same direction, and a contact direction also becomes the same direction. Although details will be described later, when the image sensor unit 9 is assembled, the sensor substrate 8 is attached after the rod lens array 6 and the illumination device 2 are inserted and attached.

16 is an original to be read, and 18 is a transparent glass original support. Reference numeral 17 denotes an external terminal. The image signal is assembled at the lower part of the sensor substrate 8 and sent to a control circuit (not shown) through the external terminal 17 that is electrically connected to form an image.

In the present embodiment, the illumination device 2 stored in the frame 5 is configured to extend in a direction orthogonal to the sub-scanning direction of the image sensor unit 9, that is, in the main scanning direction. The light source unit 1 mounted on the sensor substrate 8 is disposed opposite to one or both end faces of the lighting device 2, and light emitted from the light source unit 1 is guided into the light guide 3 of the lighting device 2. The document 16 is irradiated in a line and substantially uniformly with the amount of illumination over the longitudinal direction.

The light emitted from the illuminating device 2 irradiates the document 16 on the document support table 18 via the document support table 18, and the light (read image) reflected by the document 16 is collected by the rod lens array 6, and the sensor. An image is formed on the sensor array 7 mounted on the surface of the substrate 8. The sensor array 7 photoelectrically converts the received light into an electrical signal. The image signal is sent to a control circuit (not shown) through an external terminal 17 assembled at the bottom of the sensor substrate 8 to form an image.

Next, FIGS. 2A to 2D are views showing an assembly process of the image sensor unit 9 according to the first embodiment. Next, an assembly process of the image sensor unit 9 will be described with reference to FIGS. 2A to 2D. In these drawings, reference numeral 19 denotes a work table used for assembly.

FIG. 2A is a view showing a state where the frame 5 is installed on the work table 19 upside down from FIG. In this state, the first positioning unit 10 that holds the illumination device 2, the second positioning unit 12 that holds the rod lens array 6, and the third positioning that holds the sensor substrate 8 are provided on the frame 5. The part 14 is opened upward.

FIG. 2B shows that the lighting device 2 is brought into contact with the contact surface 10A of the first positioning unit 10 by being assembled from above, that is, pushed in so as to get over the locking unit 11, and is engaged by the locking unit 11. It is the figure which showed the state stopped. Here, the illumination device 2 is described as having a shape in which the light guide 3 is provided with the light guide 3. However, the illumination device 2 may be configured only by the light guide 3 without the light guide cover 4. .

FIG. 2C shows that the rod lens array 6 is brought into contact with the contact surface 12A of the second positioning portion 12 by being assembled from above, that is, pushed in so as to get over the locking portion 13, and the second locking portion 12 It is the figure which showed the state latched by the part 13. FIG. Here, the illumination device 2 is inserted first, but the effect is the same when the rod lens array 6 is first, and the order of insertion of the illumination device 2 and the rod lens array may be reversed.

FIG. 2D shows that the sensor substrate 8 is brought into contact with the contact surface 14A of the third positioning portion 14 by being assembled from above, that is, pushed over the locking portion 15, and the third locking portion. It is the figure which showed the state latched by 15. FIG. Here, first, the light source unit 1 is assembled from above into the gap with the end surface in the longitudinal direction of the illumination device 2 in the first positioning unit 10. Next, the sensor substrate 8 is similarly brought into contact with the positioning portion 14 by being assembled from above and locked by the locking portion 15. Thereafter, the light source unit 1 is soldered to the sensor substrate 8 from above.

Thereby, the sensor array 7 on the sensor substrate 8 is fixed at the focal position of the rod lens array 6. Thereafter, the external terminal 17 is soldered to the sensor substrate 8 from above, and the assembly operation is completed.

The light source unit 1 and the external terminal 17 may be soldered to the sensor substrate 8 in advance. Moreover, you may be the structure provided with the light source unit 1 at the both ends of the illuminating device 2. FIG.

Through the above steps, the components attached to the frame 5 can be assembled by being assembled from the same direction. Therefore, it is not necessary for the operator to set the frame 5 upside down on the work table 19, and the assembly of the image sensor unit 9 can be remarkably simplified. Specifically, when compared with the conventional case, the man-hour can be reduced to about 1/2 to 1/3, the assembly time can be shortened, the intrusion of dust etc. into the image sensor unit 9 can be reduced, and the assembly loss is also reduced. Can be reduced.

Further, by making the contact surfaces of the constituent members in the same direction, the contact surface 10A of the illuminating device 2 and the contact surface 14A of the sensor substrate 8 become the assembly reference for determining the focal position. When an assembly error occurs during the assembly, the error occurs in the same direction as the respective assembly directions. As a result, each assembly error does not accumulate and assembly accuracy can be improved (see FIGS. 3A and 3B).

3A and 3B will be used to describe the effect of improving the assembly accuracy by the structure according to the present invention. FIG. 3A shows a conventional structure, and FIG. 3B shows a structure according to the present invention. 3A and 3B, reference numeral 12A denotes a contact surface between the frame and the rod lens array 6, and reference numeral 14A denotes a contact surface between the frame and the sensor substrate 8. Here, it is assumed that an assembly error α occurs in the contact surface 12A and an assembly error β occurs in the contact surface 14A.

When the contact surface 12A with the rod lens array 6 and the contact surface 14A with the sensor substrate 8 are opposite to each other as in the conventional structure, the assembly error α generated on the contact surface 12A and the assembly error β generated on the contact surface 14A. Will be accumulated, resulting in an assembly error of “α + β”.

On the other hand, in the structure according to the present invention, since the contact surface 12A with the rod lens array 6 and the contact surface 14A with the sensor substrate 8 are in the same direction, the assembly error α generated on the contact surface 12A and the contact surface 14A. As a result, the assembly error β generated in the above is absorbed by each other, and the assembly error of “α−β” is suppressed.

Specifically, when compared with the conventional case, for example, when an assembly error of 0.05 mm occurs in each of the focal positions in the vertical direction (optical axis direction), 150 LPI (Line Per Inch) -MTF (Modulation) with respect to the focal position. Transfer
It is possible to provide the image sensor unit 9 having a small variation of about 5% in terms of (Function) value and about 10% in terms of 150 LPI-MTF value with respect to a deviation of 0.1 mm from the focal position.

<Second Embodiment>
Next, a second embodiment of the present invention will be described. FIG. 4 shows a contact image sensor unit (CIS; Contact) according to the second embodiment of the present invention.
It is sectional drawing in the subscanning direction of (Image Sensor). The same constituent elements as those in the first embodiment are denoted by the same reference numerals.

In the image sensor unit 9 'shown in FIG. 4, two illumination devices 2 are incorporated in order to increase the amount of illumination light. In general, this type of image sensor unit 9 'can reduce the reading time per line by increasing the amount of irradiation light, and thus can increase the number of readings per time, and is applied to a high-speed scanner or the like. .

In the image sensor unit 9 ′ according to the present embodiment, as in the first embodiment, the components attached to the frame 5 ′ can be assembled by being assembled from one direction. The contact direction of the structural member with respect to the frame 5 'is also the same direction. As a result, the same effects as those of the first embodiment can be obtained.

The first embodiment and the second embodiment of the present invention have been described above. In these embodiments, the structural member is structured to be locked by an elastic locking portion. However, as shown in FIG. 5, after the positioning of each structural member, a photo-curing type, a thermosetting type, a natural-curing type. It may be fixed by an adhesive 20 such as. Further, it may be fixed by heat caulking or high frequency fusion.

Moreover, in 1st Embodiment and 2nd Embodiment, although it is the structure provided with the light source unit 1 in the end surface of the one side of the longitudinal direction of the illuminating device 2, or both end surfaces, as the light source unit 1, for example, LED etc. May be arranged on the sensor substrate 8 in a straight line. In this case, the light source unit 1 is disposed to face along the longitudinal direction of the illumination device 2.

In the first embodiment and the second embodiment, the light source unit 1 and the sensor array 7 are connected to one substrate. However, even if the substrate is divided into a plurality of substrates, such as separate substrates. I do not care. In the case where the positioning portions are provided at this time, the effects of the present invention can be obtained by opening the positioning portions in the same direction and setting the assembling directions at the time of assembly to the same direction.

In the first embodiment and the second embodiment, the lighting device 2 includes the light guide 3 and the light guide cover 4. However, depending on the configuration of the image sensor unit 9, the light guide The cover 4 may be omitted.

The image sensor unit of the present invention is an effective technique as an image reading apparatus such as an image scanner, a facsimile machine, a copying machine, or the like. According to the configuration of the present invention, the assembly of the image sensor unit can be remarkably simplified, and the troublesome focus adjustment work can be omitted, so that the cost for the assembly can be greatly reduced and the assembly accuracy can be improved. In addition, since it is not necessary for the operator to assemble the frame while turning it upside down on the workbench, it is possible to reduce the intrusion of dust and the like into the image sensor unit, and to reduce the assembly loss.

Claims (10)

1. An image sensor unit comprising: a sensor substrate on which a plurality of photoelectric conversion elements are mounted; an illumination device that irradiates light on a document; and a lens array that forms an image of reflected light from the document on the photoelectric conversion element. ,
   A frame for holding the sensor substrate, the illumination device, and the lens array;
   Forming a first positioning unit for holding the illumination device, a second positioning unit for holding the lens array, and a third positioning unit for holding the sensor substrate on the frame;
   An image sensor unit, wherein the first positioning portion, the second positioning portion, and the third positioning portion are opened in the same direction.
2. The first positioning unit, the second positioning unit, and the third positioning unit are opened to incorporate the illumination device, the lens array, and the sensor substrate. The image sensor unit described.
3. The first positioning unit, the second positioning unit, and the third positioning unit each include a locking unit that locks the illumination device, the lens array, and the sensor substrate. The image sensor unit according to claim 1.
4. The contact direction between at least the lens array and the second positioning portion and the contact direction between the sensor substrate and the third positioning portion are at least the same direction. The image sensor unit according to any one of the above.
5. The illumination device includes a light guide that guides light from a light source to a document,
   The image sensor unit according to any one of claims 1 to 4, wherein the light source is mounted in parallel to the light guide and mounted on the sensor substrate.
6. An image including an image sensor unit including a sensor substrate on which a plurality of photoelectric conversion elements are mounted, an illumination device that irradiates light on the original, and a lens array that forms an image of reflected light from the original on the photoelectric conversion element A reading device,
   A frame for holding the sensor substrate, the illumination device, and the lens array;
   Forming a first positioning unit for holding the illumination device, a second positioning unit for holding the lens array, and a third positioning unit for holding the sensor substrate on the frame;
   An image reading apparatus, wherein the first positioning unit, the second positioning unit, and the third positioning unit are opened in the same direction.
7. The first positioning portion, the second positioning portion, and the third positioning portion are opened to incorporate the illumination device, the lens array, and the sensor substrate. The image reading apparatus described.
8. The first positioning unit, the second positioning unit, and the third positioning unit each include a locking unit that locks the illumination device, the lens array, and the sensor substrate. The image reading apparatus according to claim 6 or 7.
9. The contact direction between the lens array and the second positioning part and the contact direction surface between the sensor substrate and the third positioning part are at least the same direction. 9. The image reading apparatus according to any one of items 8.
10. The illumination device includes a light guide that guides light from a light source to a document,
    The image reading apparatus according to any one of claims 6 to 9, wherein the light source is provided side by side with the light guide and is mounted on the sensor substrate.

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