JPH1169104A - Image reader - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a thin profile of the reader by effectively utilizing a dead space in the reader and mounting an image processing section to the space with respect to the image reader reading image data from an original. SOLUTION: The image reader 1 is provided with a scanning means 22 that is moved nearly in a horizontal direction to scan an original, an image read means 24 that receives a reflected light from the original by the scanning to conduct photoelectric conversion, and an image processing means 10 that processes an electric signal obtained by the photoelectric conversion and is placed so that an upper end 12a at the outside of a moving range of the scanning means 22 is placed higher than a lowermost end 22c of the scanning means 22 and lower than an optical path 13 of a reflected light made incident onto the image read means 24.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an image reading apparatus for reading an image drawn on a document from a sheet-like document as image data.

[0002]

2. Description of the Related Art Conventionally, as an image reading apparatus, for example, as used in a copying machine or a scanner, a document placed on a platen glass or the like is scanned so that image data is read from the document. What is read is known. As an example of such an image reading apparatus, for example, as shown in FIG.
A second carriage 22, a lens 23, and a CCD (Charge)
Some devices include a sensor 24 and an image processing unit 25.

[0005] Here, each unit constituting the image reading apparatus 20 will be described. The first carriage 21 scans the reading surface of a document placed on the platen glass P by moving in a substantially horizontal direction, and a lamp 21 that irradiates the document on the platen glass P.
a and a mirror 21b for changing the direction of the optical axis of the reflected light obtained by the irradiation.

The second carriage 22 includes a first carriage 2
In order for the reflected light whose optical axis direction has been changed by the first mirror 21b to be incident on the CCD sensor 24, two mirrors 22a and 22b that further change the optical axis direction of the reflected light are mounted, and the original is mounted. In order to keep the optical path length between the first carriage 2 and the CCD sensor 24 constant, the first carriage 2
The moving area of the first carriage 21 is moved in a substantially horizontal direction at a speed of 1/2 of the first carriage 21.

[0005] The lens 23 is connected to the second carriage 22 and the CC.
It is provided between the D sensor 24 and below the first carriage 21, and focuses the reflected light from the second carriage 22 on the CCD sensor 24. C
The CD sensor 24 is provided below the first carriage 21 similarly to the lens 23, receives the reflected light condensed by the lens 23, and performs photoelectric conversion based on the reflected light. .

[0006] The image processing unit 25 includes a second carriage 22,
It is located below the lens 23 and the CCD sensor 24, and performs processing necessary for an electric signal obtained by photoelectric conversion by the CCD sensor 24. That is, the image processing unit 25 has a function as an amplifier that processes an electric signal from the CCD sensor 24, an A / D converter, a shading correction circuit, or a gap correction circuit.

In the image reading apparatus 20 having such a configuration,
When a document is placed on the platen glass P, the first carriage 21 moves in a substantially horizontal direction, and scans the document on the platen glass P. When the first carriage 21 scans the original, the reflected light from the original obtained by the irradiation of the lamp 21a of the first carriage 21 is reflected by the mirror 21b of the first carriage 21 and the mirror 22 of the second carriage 22.
After the optical axis direction is changed by a and 22b, the lens 2
The light is incident on the CCD sensor 24 via 3. And C
The electric signal obtained by the photoelectric conversion in the CD sensor 24 is processed by the image processing unit 25. In this manner, the image reading device 20 reads an image drawn on a document on the platen glass P as image data.

[0008]

By the way, in recent years, with the spread of what is called a desktop type, there has been a demand for a thinner image reading apparatus suitable for use on a desk or the like.

However, the image reading device 20 described above
In the embodiment, the image processing unit 25 is disposed below the scanning system including the first carriage 21 and the second carriage 22 and the imaging system including the lens 23 and the CCD sensor 24. Therefore, a space for the scanning system and the imaging system and a space for the image processing unit 25 are required. That is, the image reading device 20
Since the scanning system, the imaging system, and the image processing unit 25 are hierarchically arranged, even if there is a space or the like that is not effectively used in the apparatus, at least the scanning system in the height direction is used. Therefore, a space for the imaging system and the image processing unit 25 is required, and as a result, it is difficult to reduce the thickness to a certain degree or more.

[0010] In addition to the above-described image reading apparatus 20, an image processing section is mounted on the upper part of the apparatus (Japanese Patent Laid-Open No. Hei.
Japanese Patent Application Laid-Open No. 260866) and an image processing unit mounted on the bottom of the apparatus casing (see Japanese Patent Application Laid-Open No. 63-43164).
Since the imaging system and the image processing units are arranged hierarchically as in the above-described case, it is difficult to reduce the thickness to a certain degree or more. In addition, in these image reading apparatuses, there is a possibility that the integrity may be impaired depending on the mounting position of the image processing unit.

In order to reduce the thickness of the mirror, for example, as shown in FIG.
It is conceivable to provide a C-chamfer 26 at the ends of the b, 22a, 22b to reduce the space in the height direction for the scanning system. For this purpose, the mirrors 21b, 22a, 22b are used.
It is necessary to perform C-chamfering on the end of the device, which results in an increase in the cost of the apparatus.

Accordingly, the present invention provides an image reading device capable of realizing a thinner device without increasing the cost of the device by mounting an image processing unit by effectively utilizing an empty space in the device. It is intended to provide a device.

[0013]

According to the present invention, there is provided an image reading apparatus devised to achieve the above-mentioned object, comprising: a scanning means for scanning a document by moving in a substantially horizontal direction; Image reading means for performing photoelectric conversion by receiving reflected light from a document obtained by scanning, and electrical components required for processing an electrical signal obtained by photoelectric conversion in the image reading means, The upper end of a portion corresponding to the outside of the moving range of the scanning unit is disposed above the lowermost end of the scanning unit and below the optical path of reflected light incident on the image reading unit. Image processing means.

According to the image reading apparatus having the above structure, the upper end of the image processing means is located outside the moving range of the scanning means.
It is located above the lowermost end of the scanning means and below the optical path of the reflected light entering the image reading means. Therefore, in this image reading apparatus, the space required for the scanning means and the image reading means and the space required for the image processing means are moved from the lowermost end of the scanning means to the image reading means in the height direction. It overlaps only up to the optical path of the incident reflected light, and the size in the height direction is smaller than when these are arranged hierarchically.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an image reading apparatus according to the present invention will be described with reference to the drawings. FIG. 1 is a side sectional view illustrating a schematic configuration of an image reading apparatus 1 according to the present embodiment.
Here, the same components as those of the above-described conventional one (see FIG. 5) are given the same reference numerals, and description thereof will be omitted.

As shown in FIG. 1, an image reading apparatus 1 according to this embodiment includes a first carriage 21 and a second carriage 2.
2, a lens 23, a CCD sensor 24, and an image processing unit 10.

Of these constructions, the second carriage 22 moves the half-moving area of the first carriage 21 in a substantially horizontal direction at half the speed of the first carriage 21 in the same manner as the conventional one. Therefore, even if the first carriage 21 scans the original on the platen glass P, the second carriage 22 and the lens 23 hold the second carriage.
An unscanned area outside the moving range of the carriage 22 will occur. The CCD sensor 24 may be, for example, a MOS (Metal Oxide Sequential) as long as the CCD sensor 24 receives reflected light from a document placed on the platen glass P and performs photoelectric conversion.
It may be a (conductor) type linear sensor.

Incidentally, in the image reading apparatus 1, unlike the conventional one, the image processing section 10 is formed as described below. The image processing unit 10 is provided below the second carriage 22, the lens 23, and the CCD sensor 24. However, the image processing unit 10
It is assumed that a part of is located in the unscanned area of the second carriage 22, and the other part is located within the moving range of the second carriage 22.

The image processing unit 10 includes, for example, an amplifier,
Printed circuit board 1 having a function as an A / D converter, a shading correction circuit, or a gap correction circuit
1 and a shield cover 12 made of a thin metal plate or the like and covering the upper surface of the printed circuit board 11,
The printed circuit board 11 performs necessary processing on the electric signal from the CCD sensor 24. Therefore, the printed circuit board 11 and the CCD sensor 2
4 is connected by a cable (not shown).
Note that the image processing unit 10 may have an electric component such as a cooling fan in addition to the printed circuit board 11.

In such an image processing unit 10, the upper end (upper surface) 12 a of the portion of the shield cover 12 located in the unscanned area of the second carriage 22 is higher than the lowermost end 22 c of the second carriage 22. And lens 2
3 and optical path 13 of reflected light incident on CCD sensor 24
It is formed so that it may be located below. That is,
The shield cover 12 is formed in a stepped shape having different heights at an upper end portion 12a located in an unscanned area of the second carriage 22 and an upper surface 12b of a portion located within a movement range of the second carriage 22. ing. The upper surface 12
b is located below the lowermost end 22c of the second carriage 22.

As shown in FIG. 2, the printed circuit board 11 covered by the shield cover 12 includes an electronic component (semiconductor device or the like) 11a for processing an electric signal from the CCD sensor 24 and an upper surface of the printed circuit board 11. It is mounted so as to protrude to the side, that is, above the image processing unit 10. However, in a normal circuit board, electronic components are mounted on the entire surface of the board as shown in FIG. 2B. However, in the printed circuit board 11, as shown in FIG. The components, particularly the electronic components 11a having a large protrusion amount, are mounted in a state of being offset so as to be located in the unscanned area of the second carriage 22. As a result, on the printed circuit board 11, the amount of protrusion of the electronic component in a portion within the movement range of the second carriage 22 is reduced.

By arranging the image processing section 10 having the printed circuit board 11 and the shield cover 12 below the second carriage 22, the lens 23, and the CCD sensor 24, the image reading apparatus 1 In the unscanned area of the second carriage 22, the upper end 12a of the image processing unit 10 is located above the lowermost end 22c of the scanning system including the first carriage 21 and the second carriage 22, and the lens 23 and the CCD It is located below the optical path 13 of the reflected light incident on the imaging system composed of the sensor 24. That is, in the image reading device 1, in the height direction, the space required for the scanning system and the imaging system and the space required for the image processing unit 10 are formed from the lowermost end 22c of the scanning system. It overlaps only up to the optical path 13 of the reflected light entering the image system.

Therefore, in the image reading apparatus 1, the height of the scanning system and the image forming system and the height of the image processing unit 10 are increased by an amount corresponding to the overlap of the respective spaces as compared with the case where the image processing unit 10 is arranged in a hierarchical manner. The size in the direction can be reduced. That is, in the unscanned area of the second carriage 22, the empty space between the lowermost end 22c of the scanning system and the optical path 13 of the reflected light to the imaging system is effectively used, so that the apparatus can be easily made thinner. It can be realized. Moreover, since the apparatus can be made thinner without performing the C-chamfering process on the ends of the mirrors 21b, 22a, 22b used in the scanning system, the cost does not increase due to the thinner apparatus.

The shield cover 1 of the image processing unit 10
2, a C chamfer 22 provided on the unscanned area side of the lowermost end 22c of the second carriage 22, as shown in FIG.
d, a shield cover 12 formed in a step shape
May have a shape that matches the C-chamfered portion 22d. In this case, the capacity of the convex portion formed by the upper end portion 12a and the step portion 12c of the shield cover 12 can be further increased, so that the space in the image reading device 1 can be more effectively used. Thus, it is possible to further reduce the thickness of the device.

In the image reading apparatus 1, the image processing section 10 has a printed circuit board 11, and the printed circuit board 11 processes an electric signal from the CCD sensor 24. That is, in the image reading device 1, the printed circuit board 11 necessary for processing the electric signal from the CCD sensor 24 is mounted in the image reading device 1. Therefore, in the image reading apparatus 1, the complexity of the cable processing can be suppressed as much as possible, and the integrity may be impaired as in the case where the image processing unit is mounted on the top of the apparatus or the bottom of the apparatus casing. Absent.

In addition, the printed circuit board 11 of the image reading apparatus 1 has an electronic component 11 having a large projection amount on the board.
a is mounted on a portion of the second carriage 22 corresponding to the unscanned area. Therefore, in this image reading device 1,
The lowermost end 22 of the scanning system in the unscanned area of the second carriage 22
A space, such as between the optical path 13 and the optical path 13 of the reflected light to the image forming system, is allocated to the electronic components 11 on the printed circuit board 11.
It can be effectively used as space for a. Further, the height of the printed circuit board 11 in a portion corresponding to the moving range of the second carriage 22 can be reduced. As a result, in the image reading apparatus 1, it is possible to more reliably reduce the thickness of the apparatus by effectively utilizing the space in the apparatus.

In the image reading apparatus 1, the printed circuit board 11 is covered by the shield cover 12. Furthermore, with the thinning of the device due to the effective use of empty space, the printed circuit board 11 and the CCD sensor
The cable length between them is also shorter. Therefore, in the image reading apparatus 1, for example, the first carriage 2
Even if a noise source such as an electromagnetic wave is generated when the first and second carriages 22 move, it is possible to minimize the influence of the noise source on the printed circuit board 11, and to reduce the thickness of the device. In addition, the quality of image data read from a document can be stabilized.

By the way, in this image reading apparatus 1,
A lens 23 is provided between the second carriage 22 and the CCD sensor 24, and the lens 23
The reflected light from the carriage 22 is focused on the CCD sensor 24. In other words, on the optical path 13 of the reflected light incident on the CCD sensor 24, as shown in FIG.
It has a fan shape spreading toward the carriage 22. Therefore, the space outside the optical path width 13a of the reflected light and below the lower end of the first carriage 21 is:
Even if it is above the optical path 13 of the reflected light incident on the CCD sensor 24, it means that it is an empty space.

For this reason, in the image reading apparatus 1, the shield cover 12 may be formed in the following shape. That is, the upper surface 12b of the shield cover 12 is positioned below the lowermost end 22c of the second carriage 22 in a portion located within the movement range of the second carriage 22. In the unscanned area of the second carriage 22 and inside the optical path width 13a of the reflected light incident on the CCD sensor 24, the upper end 12a of the shield cover 12
But above the lowermost end 22c of the second carriage 22,
In addition, it is positioned below the optical path 13 of the reflected light. Further, the optical path width 13a of the reflected light incident on the CCD sensor 24 in the unscanned area of the second carriage 22
On the outer side, the upper surface 12c of the shield cover 12
The first carriage 21 is located above the optical path 13 of the reflected light and below the lower end of the first carriage 21.

If the electronic components 11a on the printed circuit board 11 are arranged in accordance with the shape of the shield cover 12, the outer side of the optical path width 13a of the reflected light and
The empty space below the lower end of the first carriage 21 is
It can be used as a space for the electronic component 11a on the printed circuit board 11. Therefore, in this case, it is possible to further effectively use the empty space, and it is possible to further reduce the thickness of the device.

In the above-described embodiment, the case where the empty space in the unscanned area of the second carriage 22 is used as the space for the electronic component 11a on the printed circuit board 11 has been described. Even when the space is used as a space for electrical components such as a cooling fan of the processing unit 10, the empty space is used as a space for the image processing unit 10, and the space is effectively used in the apparatus. Can be reduced in thickness.

In the above-described embodiment, the case where the image processing unit 10 is covered by the shield cover 12 has been described, but the present invention is not limited to this. For example, even if the shield cover 12 is not provided, the upper end of the image processing unit 10 is positioned at the lowermost end 22c of the scanning system.
The above-described effect can be obtained by setting the position above the optical path 13 and below the optical path 13 of the reflected light.

[0033]

As described above, according to the image reading apparatus of the present invention, the upper end of the image processing means is located above the lowermost end of the scanning means outside the moving range of the scanning means, and
It is located below the optical path of the reflected light to the image reading means. In other words, in this image reading apparatus, by effectively utilizing an empty space outside the moving range of the scanning means as a space for the image processing means, the thickness of the apparatus can be easily reduced. In addition, there is no possibility that the maintainability is impaired or the cost is increased.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing a schematic configuration of an example of an embodiment of an image reading apparatus according to the present invention.

FIG. 2 is a diagram showing an outline of a printed circuit board;
(A) is a plan view and a side view showing an example of a printed circuit board mounted on the image reading apparatus according to the present invention, (b)
FIG. 1 is a plan view and a side view showing a general printed circuit board.

FIG. 3 is an explanatory diagram illustrating a main part of a shield cover that covers a printed circuit board.

FIG. 4 is a plan view illustrating an optical path width of reflected light incident on an imaging system.

FIG. 5 is a side sectional view showing a schematic configuration of an example of a conventional image reading apparatus.

FIG. 6 is an explanatory diagram of a C chamfer provided at a mirror end;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Image reading apparatus, 10 ... Image processing part, 11 ... Printed circuit board, 11a ... Electronic components, 12 ... Shield cover,
12a: Upper end, 13: Optical path of reflected light, 13a: Optical path width of reflected light, 21: First carriage, 22: Second carriage, 22c: Lowermost end, 23: Lens, 24: CCD sensor

Claims (4)

[Claims] A scanning unit that scans the original by moving in a substantially horizontal direction; an image reading unit that performs a photoelectric conversion by receiving reflected light from the original obtained by scanning by the scanning unit; It has electrical components necessary for processing the electrical signal obtained by the photoelectric conversion in the reading means, and the upper end of a portion corresponding to outside the moving range of the scanning means is higher than the lowermost end of the scanning means. And an image processing means disposed below the optical path of the reflected light incident on the image reading means. 2. An image reading apparatus according to claim 1, wherein said image processing means has a printed circuit board for processing said electric signal. 3. The printed circuit board according to claim 1, wherein a mounting component protruding from an upper surface of the printed circuit board is arranged in a portion corresponding to a position outside a moving range of the scanning unit. 2. The image reading device according to 2. 4. When a condensing means for condensing reflected light from a document to the image reading means is provided between the scanning means and the image reading means, the image processing means comprises:
The upper end of a portion corresponding to the outer side of the optical path width of the reflected light incident on the image reading means is disposed above the optical path of the reflected light incident on the image reading means. The image reading device according to claim 1, 2, or 3, wherein: