JP2008283627A - Image scanner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To attain a low-profile form by reducing a size in height in an image scanner. <P>SOLUTION: The image scanner 1 is equipped with a manuscript table 2 on which a manuscript is put, a light receiving device 4, an imaging lens 5, an image scanning mirror 6, adjusting mirrors 7, 8 of optical path length, an optical path bending mirror 9, and so forth. The image scanning mirror 6 travels in order to scan an image of a manuscript and reflects light from the manuscript. The adjusting mirrors 7, 8 of optical path length travels in order to stabilize an optical path from the image scanning mirror 6 to the light receiving device 4 to reflect light reflected from the manuscript by the image scanning mirror 6. The optical path bending mirror 9 reflects light reflected from the manuscript by mirror 8 of the optical path length adjusting. The imaging lens 5 receives light reflected from the manuscript by the optical path bending mirror 9 to provide an image of the manuscript on the light receiving device 4. The light receiving device 4 optically scans the image of the manuscript by receiving light from the manuscript via the imaging lens 5. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an image reading apparatus that reads an image drawn on a document.

  2. Description of the Related Art Conventionally, in an image reading apparatus such as a scanner or a copying machine, light from a document placed on a document table is reflected by a reflecting means and guided to an imaging lens. The image of the original is optically read by a light receiving device. In general, such an image reading apparatus houses a reflecting means, an imaging lens, and a light receiving device in a casing, and moves the reflecting means along the document table in the casing, thereby providing a document table. By reflecting light from different areas on the document placed on the document (that is, scanning an image of the document), an image of the entire document is read. Also, such an image reading apparatus generally has an imaging lens in order to keep the distance from the document to the imaging lens and the light receiving device constant when scanning the image of the document by moving the reflecting means. In addition, the light receiving device is moved integrally with the reflecting means (see, for example, Patent Document 1).

On the other hand, in an image reading apparatus that forms an image on a light receiving device via a reflecting means and an imaging lens, and reads the image by the light receiving device, the contrast is detected from the electrical signal detected by the light receiving device, and the reflecting means and Focusing is adjusted by driving the imaging lens (for example, see Patent Document 2), or by moving the imaging lens and the light receiving device integrally to form an image on the light receiving device. A device that adjusts the magnification is known (see, for example, Patent Document 3). Further, the first lens group having a negative refractive power and the second lens group having a positive refractive power are provided, and the focal length of the entire lens group is changed by changing the distance between the first lens group and the second lens group. An image reading zoom lens configured to do this is known (for example, see Patent Document 4).
JP-A-10-233896 Japanese Patent Laid-Open No. 10-336402 JP-A-9-233271 Japanese Patent Laid-Open No. 9-113804

  However, since the image reading apparatus described in Patent Document 1 is configured to move the imaging lens and the light receiving device integrally with the reflecting means, the movement range (that is, the arrangement location) of the imaging lens and the light receiving device. Is restricted by the enclosure. For this reason, the distance from the region on the document whose image is scanned by the reflecting means to the imaging lens and the light receiving device is set to be long in the moving direction of the reflecting means (also the moving direction of the imaging lens and the light receiving device). I can't. Therefore, in order to obtain an optical path length necessary for forming an image of a document on the light receiving device, it is necessary to return the light from the document by being reflected many times by the reflecting means and to guide it to the imaging lens. In other words, the optical path from the document to the imaging lens and the light receiving device needs to be folded many times and formed so as to overlap several times in the height direction of the image reading apparatus. As a result, the height dimension of the image reading apparatus is increased by the amount that the light from the document is folded back by the reflection means. Even if the contents disclosed in Patent Document 2 to Patent Document 4 described above are applied, the above problem cannot be solved.

  SUMMARY An advantage of some aspects of the invention is that it provides an image reading apparatus capable of reducing the height and reducing the thickness thereof.

  In order to achieve the above object, an invention according to claim 1 is placed on a document table on which a document is placed, a light receiving device that receives light and outputs a light reception output signal corresponding to a light reception level, and a document table. An image forming lens for forming an image of the original on the light receiving device, and receiving the light from the original placed on the platen by the light receiving device through the imaging lens In the image reading apparatus for optically reading the image, the image reading apparatus further includes reflecting means for reflecting the light from the document and guiding it to the imaging lens, and the reflecting means is movably supported along the document table for scanning the image of the document. The image scanning reflecting means for reflecting the light from the document in a direction parallel to the document table, and the optical path length from the image scanning reflecting means to the light receiving device are movably supported along the document table. Reflective hand for image scanning Those having an optical path length adjusting reflection means for folding back the light reflected on the document platen in a direction parallel from the original reflected by the.

  According to a second aspect of the present invention, in the image reading apparatus according to the first aspect, the image reading apparatus further includes a housing that houses the light receiving device, the imaging lens, and the reflecting means, and the light receiving device and the imaging lens are fixed to the casing. It is what.

  According to a third aspect of the present invention, in the image reading apparatus according to the second aspect, the light receiving device and the imaging lens are arranged at a position other than below the document table in the housing.

  According to a fourth aspect of the present invention, in the image reading apparatus according to the third aspect, the imaging lens changes the magnification of the image formed on the light receiving device by partial movement of the lens group constituting the imaging lens. It is a possible zoom lens.

  According to the first aspect of the present invention, when the image scanning reflecting means is moved to scan the image of the document, the optical path length adjusting reflecting means is moved to move the imaging lens and the light receiving device from the image scanning reflecting means. The optical path length from the image scanning reflecting means to the imaging lens and the light receiving device need not be moved in order to keep the optical path length constant. In addition, since it is not necessary to move the imaging lens and the light receiving device, the arrangement position of the imaging lens and the light receiving device is restricted by the configuration in which the imaging lens and the light receiving device are moved as in the conventional case. Absent. Accordingly, it is possible to set a long distance from the optical path length adjusting reflecting means to the imaging lens and the light receiving device in the moving direction of the optical path length adjusting reflecting means. As compared with the configuration in which the image is moved integrally, the optical path length necessary for forming an image of the document on the light receiving device can be obtained with a smaller number of reflections by the reflecting means. As a result, the height of the image reading device can be reduced by the amount of reflection by the reflecting means, and the image reading device can be made thinner.

  According to the second aspect of the present invention, since the light receiving device and the imaging lens are fixed to the casing, the light receiving device and the imaging lens are compared with the conventional configuration in which the light receiving device and the imaging lens move. Position accuracy is improved, and a high-quality image can be obtained.

  According to the invention of claim 3, since the light receiving device and the imaging lens are arranged at positions other than the lower side of the document table in the housing, a space that is not used for image scanning by the image scanning reflecting means, It can be effectively used as a space for arranging the light receiving device and the imaging lens, and can be further reduced in thickness.

  According to the fourth aspect of the present invention, an image reading apparatus having a function of optically enlarging and reducing a read image using a zoom lens can be reduced in thickness and a high-quality image can be obtained.

  Hereinafter, an image reading apparatus according to an embodiment of the present invention will be described with reference to the drawings. 1, 2A, 2B, and 2C show the configuration of the image reading apparatus according to the present embodiment. The image reading device 1 is a device that reads an image drawn on a document. Further, this image reading apparatus has a function of printing an image on printing paper.

  The image reading apparatus 1 includes a document table 2 on which a document is placed, a document pressing plate 3 for pressing the document, a light receiving device 4 for reading an image of the document, and a document image on the light receiving device 4. An imaging lens 5 for imaging, an image scanning mirror 6, optical path length adjusting mirrors 7, 8, and an optical path bending mirror 9, which are reflecting means for reflecting light from the document and guiding it to the imaging lens 5; And a light source 10 for irradiating the document with light.

  In addition, the image reading apparatus 1 includes a light receiving device 4, an imaging lens 5, an image scanning mirror 6, optical path length adjusting mirrors 7 and 8, an optical path bending mirror 9, and a housing 11 that houses a light source 10, and printing paper. Is loaded with a paper rest 12, a key operation unit 13 for instructing various operations of the image reading apparatus 1, and the like. The image scanning mirror 6 constitutes an image scanning reflecting means for scanning the image of the document. The optical path length from the image scanning mirror 6 to the light receiving device 4 is adjusted by the optical path length adjusting mirrors 7 and 8. Reflecting means for adjusting the optical path length to be adjusted is configured.

  The document table 2 is made of a transparent plate and is provided on the upper portion of the housing 11. The upper wall 11a of the casing 11 (that is, the upper part of the casing 11) is opened at the substantially center, and the document table 2 is provided at an opening portion of the upper wall 11a of the casing 11. The document is placed on the document table 2 with the surface on which the image is drawn facing downward. The document pressing plate 3 is rotatably provided on the upper surface of the housing 11. By opening the document pressing plate 3, the document can be placed on the document table 2, and by closing the document pressing plate 3. The document placed on the document table 2 can be pressed.

  The light receiving device 4, the imaging lens 5, the image scanning mirror 6, the optical path length adjusting mirrors 7 and 8, the optical path bending mirror 9, and the light source 10 are as shown in FIGS. 2 (a), 2 (b), and 2 (c). , Provided inside the housing 11. The light source 10 irradiates light on the document placed on the document table 2. The image scanning mirror 6, the optical path length adjusting mirrors 7 and 8, and the optical path bending mirror 9 reflect light from the document and guide it to the imaging lens 5. The imaging lens 5 receives light from the document through the image scanning mirror 6, optical path length adjusting mirrors 7 and 8, and optical path bending mirror 9, and forms an image of the document on the light receiving device 4. . That is, the image reading apparatus 1 transmits light from the document placed on the document table 2 via the image scanning mirror 6, the optical path length adjusting mirrors 7 and 8, the optical path bending mirror 9, and the imaging lens 5. By receiving light by the light receiving device 4, an image of the original is optically read. Details of the light receiving device 4, the imaging lens 5, the image scanning mirror 6, the optical path length adjusting mirrors 7 and 8, the optical path bending mirror 9, and the light source 10 will be described later.

  The paper rest 12 is provided on the back of the housing 11. Printing paper is loaded into the paper rest 12. The printing paper placed on the paper rest 12 is taken into the housing 11 by a paper transport unit (not shown), and after an image is printed by the image printing unit (not shown), the printing paper is placed outside the housing 11 from the paper discharge port 11b. To be discharged. The key operation unit 13 is provided on the upper surface of the upper wall 11 a of the housing 11 and is operated by the user to instruct various operations of the image reading apparatus 1.

  Next, referring to FIGS. 2A, 2B and 2C, the light receiving device 4, the imaging lens 5, the image scanning mirror 6, the optical path length adjusting mirrors 7 and 8, the optical path bending mirror 9, The configuration of the light source 10 will be described.

  The light receiving device 4 uses a CCD line sensor and has a large number of light receiving elements arranged in one direction. The light receiving device 4 receives light by a large number of light receiving elements arranged in one direction, reads an image in a line shape in the light receiving element arrangement direction (main scanning direction), and according to the light receiving level of each light receiving element. A light reception output signal (that corresponds to the read image) is output. The light receiving device 4 is disposed at a position below the upper wall 11a of the housing 11 (that is, a position other than the position below the document table 2) so that the light receiving surface faces downward, and the arrangement direction of the light receiving elements will be described later. It is fixed to the housing 11 so as to be substantially orthogonal to the moving direction of the image scanning mirror 6.

  The imaging lens 5 is a zoom lens having a variable focal length, and has a plurality of lenses. The imaging lens 5 can change the magnification of the image formed on the light receiving device 4 by changing the focal length by the partial movement of the lens group constituting the imaging lens 5. The imaging lens 5 is disposed at a position below the light receiving device 4 (that is, a position other than the position below the document table 2) and is fixed to the housing 11.

  The image scanning mirror 6 is a reflection mirror for scanning an image of a document placed on the document table 2. The image scanning mirror 6 is supported inside a housing 11 by a support 15 that is controlled to move. The support body 15 is slidably supported by the guide rail 16, and the guide rail 16 is orthogonal to the arrangement direction of the light receiving elements of the light receiving device 4 along the document table 2 and the upper wall 11 a of the housing 11. It extends to. That is, the image scanning mirror 6 is movably supported by the support 15 and the guide rail 16, and is orthogonal to the arrangement direction of the light receiving elements of the light receiving device 4 along the document table 2 and the upper wall 11 a of the housing 11. It is designed to reciprocate in the direction of

  The image scanning mirror 6 passes through a lower position of the document table 2 from a predetermined standby position (position shown in FIG. 2A) set on one end side of the guide rail 16 and the other end of the guide rail 16. It is configured to reciprocate within a range up to a movement end point position (position shown in FIG. 2C) set on the side. The standby position of the image scanning mirror 6 is set to a position below the upper wall 11a of the casing 11 on the side opposite to the position where the light receiving device 4 and the imaging lens 5 are arranged (that is, a position other than the position below the document table 2). ing.

  The image scanning mirror 6 reflects light from the document placed on the document table 2 in a direction parallel to the document table 2 and is orthogonal to the moving direction of the image scanning mirror 6. Is getting longer.

  The optical path length adjusting mirrors 7 and 8 are mirrors for adjusting the optical path length from the image scanning mirror 6 (from the document placed on the document table 2) to the light receiving device 4. The optical path length adjusting mirrors 7 and 8 are supported by a support body 17 that is controlled to move inside the housing 11. The support body 17 is slidably supported on the guide rail 18, and the guide rail 18 extends along the guide rail 16 in parallel. In other words, the optical path length adjusting mirrors 7 and 8 are supported by the support 17 and the guide rail 18 so as to be movable, and the arrangement of the light receiving elements of the light receiving device 4 along the document table 2 and the upper wall 11a of the casing 11. They are reciprocally moved together in a direction orthogonal to the direction (that is, the same direction as the moving direction of the image scanning mirror 6). The optical path length adjusting mirror 7 moves at the same height as the image scanning mirror 6.

  The optical path length adjusting mirrors 7 and 8 move from a predetermined standby position (position shown in FIG. 2A) set on one end side of the guide rail 18 to a movement end point position (FIG. 2C) below the document table 2. It is designed to reciprocate within the range up to the position shown in (). The standby positions of the optical path length adjusting mirrors 7 and 8 are below the upper wall 11a of the housing 11 on the opposite side of the arrangement positions of the light receiving device 4 and the imaging lens 5 as in the standby position of the image scanning mirror 6. It is set to a position (that is, a position other than the lower side of the document table 2). That is, the distances between the optical path length adjusting mirrors 7 and 8 and the light receiving device 4 and the imaging lens 5 are set as long as possible in the moving direction of the optical path length adjusting mirrors 7 and 8.

  The optical path length adjusting mirror 7 reflects light from the original reflected by the image scanning mirror 6 downward (in a direction perpendicular to the original table 2). The optical path length adjusting mirror 8 The light from the document reflected by the optical path length adjusting mirror 7 is reflected in the direction opposite to the traveling direction of the light from the document reflected by the image scanning mirror 6 (a direction parallel to the document table 2). ing. That is, the optical path length adjusting mirrors 7 and 8 are configured to return the light from the document reflected by the image scanning mirror 6 and reflect it in a direction parallel to the document table 2. Further, the optical path length adjusting mirrors 7 and 8 are elongated in the direction orthogonal to the moving direction of the optical path length adjusting mirrors 7 and 8.

  The optical path bending mirror 9 is a mirror for bending the optical path from the optical path length adjusting mirror 8 to the imaging lens 5. The optical path bending mirror 9 is fixed to the housing 11 inside the housing 11. The optical path bending mirror 9 is located at the same height as the optical path length adjusting mirror 8 and at a position below the imaging lens 5 (that is, a position other than the position below the document table 2).

  The optical path bending mirror 9 reflects light from the original reflected by the optical path length adjusting mirror 8 upward (in a direction perpendicular to the original table 2), and the optical path length adjusting mirror 7 , 8 in the direction perpendicular to the moving direction. The light from the document reflected by the optical path bending mirror 9 enters the imaging lens 5 and is received by the light receiving device 4 through the imaging lens 5.

  The light source 10 is supported by the support 15. Therefore, the light source 10 moves together with the image scanning mirror 6. The light source 10 is a cold cathode tube lamp and is controlled to be turned on and off, and emits light when turned on. Light emitted from the light source 10 is near the lower surface of the upper wall 11a of the housing 11 when the image scanning mirror 6 is positioned below the upper wall 11a of the housing 11 (the image scanning mirror 6 is the original table 2). Is located near the upper surface of the document table 2.

  With such a configuration, the light from the document placed on the document table 2 is reflected by the image scanning mirror 6, the optical path length adjusting mirrors 7 and 8, and the optical path bending mirror 9 to the imaging lens 5. Incident light is received by the light receiving device 4 through the imaging lens 5. Then, by moving the image scanning mirror 6, the light receiving device 4 can receive light from different regions on the document in the moving direction of the image scanning mirror 6. That is, by moving the image scanning mirror 6, the document surface can be scanned in the sub-scanning direction (a direction orthogonal to the arrangement direction of the light receiving elements (main scanning direction) of the light receiving device 4). Further, the optical path length from the image scanning mirror 6 to the light receiving device 4 is adjusted while the light receiving device 4 receives light from the same region on the document by moving the optical path length adjusting mirrors 7 and 8. Can do.

  FIG. 3 shows an electrical block configuration of the image reading apparatus 1. In addition to the above-described configuration, the image reading apparatus 1 includes a control unit 21 including a CPU, a ROM, and a RAM for controlling the operation of the image reading apparatus 1, a scan drive mechanism 22, an optical zoom mechanism 23, an image A processing unit 24, a memory 25, an external device connection unit 26, and the like are provided. Firmware and various data for controlling the operation of the image reading apparatus 1 are stored in the ROM of the control unit 21.

  The scan drive mechanism 22 includes a motor 15 and a gear that move the support 15 and the support 17, and is supported via the gear and the like by rotating the motor under the control of the control unit 21. The body 15 and the support 17 are moved, and the image scanning mirror 6 supported by the support 15 and the optical path length adjusting mirrors 7 and 8 supported by the support 17 are moved in the sub-scanning direction. . The scan driving mechanism 22 moves the optical path length adjusting mirrors 7 and 8 in conjunction with the movement of the image scanning mirror 6, and moves the optical path length adjusting mirrors 7 and 8 to move the image scanning mirror 6. The image scanning mirror 6 is moved in the same direction as the direction by a half movement amount.

  The optical zoom mechanism 23 has an actuator or the like that partially moves a lens group constituting the imaging lens 5. The optical zoom mechanism 23 drives the actuator under the control of the control unit 21, thereby moving the imaging lens 5. The lens group to be configured is partially moved to enlarge or reduce the image formed on the light receiving device 4.

  The image processing unit 24 generates image data corresponding to the image read by the light receiving device 4 based on the light reception output signal of the light receiving device 4 under the control of the control unit 21. The memory 25 stores image data (image data of an image read by the light receiving device 4) generated by the image processing unit 24 under the control of the control unit 21 and the like. The external device connection unit 26 transmits and receives various signals to and from an external device such as a personal computer under the control of the control unit 21.

  In response to the operation of the key operation unit 13, the control unit 21 performs a power-on operation of the image reading apparatus 1, a document image reading operation for reading an image from a document, setting an image reading magnification in the document image reading operation, Various operations of the image reading apparatus 1 such as a printing operation for printing are controlled.

  The document image reading operation is performed as follows under the control of the control unit 21. That is, when an image reading instruction is made by operating the key operation unit 13, the light source 10 is turned on, and the scan scanning mechanism 22 moves the image scanning mirror 6 and the optical path length adjusting mirrors 7 and 8 in the sub-scanning direction. Then, the light receiving device 4 reads an image in a line shape in the main scanning direction at a predetermined cycle.

  When the light source 10 is turned on, the light emitted from the light source 10 is irradiated onto the document placed on the document table 2, and the reflected light from the document is reflected by the image scanning mirror 6 and the optical path length adjusting mirrors 7, 8, Reflected by the optical path bending mirror 9 and incident on the imaging lens 5, an image of the original is imaged on the light receiving device 4 by the imaging lens 5.

  Further, the image scanning mirror 6 moves in the sub-scanning direction below the document table 2, so that light from different regions of the document placed on the document table 2 in the sub-scanning direction is caused by the image scanning mirror 6. The light is reflected and enters the imaging lens 5. As described above, the optical path length adjusting mirrors 7 and 8 are moved in the same direction as the moving direction of the image scanning mirror 6 in the same amount as the moving direction of the image scanning mirror 6 with a movement amount that is half of the moving amount of the image scanning mirror 6. It is supposed to move. Accordingly, while the image scanning mirror 6 moves in the sub scanning direction in the lower position of the document table 2, the optical path length from the image scanning mirror 6 to the light receiving device 4 is kept constant, and the original scanning direction in the sub scanning direction is maintained. Images of different areas are formed on the light receiving device 4.

  Then, by moving the image scanning mirror 6 in the sub-scanning direction and reading the image in a line shape in the main scanning direction by the light receiving device 4 at a predetermined cycle, images of different regions in the sub-scanning direction of the document are obtained. Are read in the main scanning direction, and an image of the entire original is read. In this way, the control unit 21 performs the document image reading operation.

  Further, the setting of the image reading magnification in the document image reading operation is performed as follows under the control of the control unit 21. That is, when an instruction to set the image reading magnification is made by operating the key operation unit 13, the lens group constituting the imaging lens 5 is partially moved by the optical zoom mechanism 23 so that the designated image reading magnification is obtained. Thus, the image reading magnification is set by enlarging or reducing the image formed on the light receiving device 4. By enlarging and reducing the image formed on the light receiving device 4, the enlarged and reduced image is read by the light receiving device 4. As a result, in the original image reading operation, the original image is read at the set image reading magnification.

  According to the image reading apparatus 1 having such a configuration, when the image scanning mirror 6 is moved to scan the image of the document, the optical path length adjusting mirrors 7 and 8 are moved to move the image scanning mirror 6 from the image scanning mirror 6. The optical path length to the imaging lens 5 and the light receiving device 4 is kept constant. For this reason, the arrangement | positioning location of the imaging lens 5 and the light-receiving device 4 does not receive the restrictions by being a structure which moves an imaging lens and a light-receiving device like the past.

  Accordingly, the distance from the optical path length adjusting mirrors 7 and 8 to the imaging lens 5 and the light receiving device 4 in the moving direction of the optical path length adjusting mirrors 7 and 8 can be set long. As compared with the configuration in which the light receiving device is moved integrally with the reflecting means, it is possible to obtain an optical path length necessary for forming an image of the document on the light receiving device 4 with a small number of reflections. As a result, the height dimension of the image reading apparatus 1 can be reduced by an amount corresponding to the small number of reflections, and the image reading apparatus 1 can be thinned.

  In addition, since the light receiving device 4 and the imaging lens 5 are fixed to the housing 11, the positions of the light receiving device 4 and the imaging lens 5 are compared with the conventional configuration in which the light receiving device and the imaging lens move. The accuracy is improved and a high-quality image can be obtained. Further, since the light receiving device 4 and the imaging lens 5 are arranged at positions other than the lower side of the document table 2 in the housing 11, a space not used for image scanning by the image scanning mirror 6 is used as the light receiving device 4. In addition, it can be effectively used as a space for disposing the imaging lens 5 and can be further reduced in thickness. In the image reading apparatus 1 having a function of optically enlarging and reducing a read image using the imaging lens 5 (zoom lens), it is possible to reduce the thickness and obtain a high-quality image. .

  In addition, this invention is not restricted to the structure of the said embodiment, A various deformation | transformation is possible. For example, light from the optical path adjustment mirror is reflected downward by the optical path bending mirror, the imaging lens is disposed below the optical path bending mirror, and the light receiving device is connected with the light receiving surface facing upward. You may arrange | position in the downward position of an image lens. The optical path bending mirror is not necessarily provided, and the imaging lens and the light receiving device may be arranged on the reflection optical path of the optical path adjustment mirror with the optical axis oriented sideways. The image scanning mirror and the optical path length adjusting mirror may be controlled to move by separate motors, or may be controlled to move by one same motor. In order to reduce the thickness of the image reading apparatus, it is desirable to arrange the image scanning mirror and the optical path length adjusting mirror close to the document table, and to shorten the distance between one of the optical path length adjusting mirrors and the other. It is desirable to do.

1 is a perspective view illustrating a schematic configuration of an image reading apparatus according to an embodiment of the present invention. (A) is a side sectional view when the image scanning mirror of the image reading apparatus is at the standby position, (b) is a side sectional view when the image scanning mirror is at a position below the document table, and (c) is a side sectional view. FIG. 4 is a side sectional view when the image scanning mirror is at a movement end point position. FIG. 3 is an electrical block configuration diagram of the image reading apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image reader 2 Document stand 3 Document holding plate 4 Light receiving device 5 Imaging lens 6 Image scanning mirror 7, 8 Optical path length adjustment mirror 9 Optical path bending mirror 10 Light source 11 Housing 11a Upper wall 11b Paper discharge port 12 Paper rest DESCRIPTION OF SYMBOLS 13 Key operation part 15 Support body 16 Guide rail 17 Support body 18 Guide rail 21 Control part 22 Scan drive mechanism 23 Optical zoom mechanism 24 Image processing part 25 Memory 26 External apparatus connection part

Claims (4)

A document table on which a document is placed, a light receiving device that receives light and outputs a light reception output signal corresponding to a light reception level, and forms an image of the document placed on the document table on the light receiving device In an image reading apparatus that optically reads an image of a document by receiving light from a document placed on the document table by the light receiving device through the imaging lens ,
A reflection means for reflecting light from the document and guiding it to the imaging lens;
The reflecting means is
Image scanning reflecting means that is movably supported along the document table for scanning an image of the document and reflects light from the document in a direction parallel to the document table;
In order to keep the optical path length from the image scanning reflecting means to the light receiving device constant, the light from the original reflected by the image scanning reflecting means is folded back by being supported movably along the original table. An optical path length adjusting reflecting means for reflecting in a direction parallel to the document table,
An image reading apparatus. A housing that houses the light receiving device, the imaging lens, and the reflecting means;
The light receiving device and the imaging lens are fixed to the housing,
The image reading apparatus according to claim 1. The light receiving device and the imaging lens are disposed at positions other than the lower side of the document table in the housing.
The image reading apparatus according to claim 2. The imaging lens is a zoom lens capable of changing a magnification of an image formed on the light receiving device by partial movement of a lens group constituting the imaging lens.
The image reading apparatus according to claim 3.

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