JP2008072305A - Image reader and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To allow a position of an imaging element to be restored to a proper relative position relation to a lens correspondingly to a structure for fixing members, which is deformed so as to change the relative position relation between the lens and the imaging element by heating of the imaging element or a temperature environment for use. <P>SOLUTION: Even if thermal deformation (thermal expansion) occurs due to a high temperature of an environment for use and the relative position of an imaging element 2 to a lens unit 1 is changed, focus positions of the imaging element 2 and the lens unit 1 are aligned with each other with such constitution that an imaging element fixing member 3 is deformed as much as the change. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a lens unit and an image pickup device, an image pickup apparatus provided with a fixing structure thereof, and an image forming apparatus on which the image pickup apparatus is mounted, and particularly relates to a technique for dealing with environmental temperature changes.

  An image pickup apparatus in a conventional image forming apparatus has a configuration in which reflected light of a target image such as a document is formed by a lens unit, and the formed reflected light is converted into an electric signal by an image pickup device to obtain image information. In general, in response to the recent demand for high reading accuracy, many proposals have been made and implemented regarding technologies that can make each optical element highly accurate and respond to changes in the usage environment. Has been.

  For example, as described in Patent Document 1, a lens position adjustment member is attached to the lens unit so that the imaging position can be maintained on the optical sensor surface even when the temperature of the usage environment changes, and the usage temperature A configuration for adjusting the position of the lens unit according to the environment has been proposed.

Further, Patent Document 2 discloses that K1 is the linear expansion coefficient K1 of a lens barrel and the linear expansion coefficient K2 of a reference member that defines the relative positional relationship between the lens barrel and an image reading member such as a CCD. There is described a configuration in which the position of the image reading member is changed by following the change of the focal position of the lens due to the change of the environmental temperature by making it larger (or smaller) than K2.
JP 2001-84352 A Japanese Patent Laid-Open No. 9-49957

  However, in the conventional technology, in the configuration described in Patent Document 1, since the light source, the mirror, the lens unit, and the optical sensor are housed in one housing, a large heat source called a light source is provided in addition to the photoelectric conversion element. Have. When the position adjustment member is attached to the lens unit, the lens unit is also close to the light source, and thus is affected by heat generated by the light source. In the scanner, the light source is normally turned off except when reading a document, and the light source is turned on only at the time of reading. For this reason, the amount of heat generated by the light source differs between when the document is scanned intermittently and when a plurality of documents are scanned continuously, which also affects the amount of extension of the lens position adjustment member. However, there is a problem that the position of the lens unit cannot be adjusted.

  Further, in Patent Document 2, as a factor that changes the focal length of a lens depending on temperature, a lens barrel that defines the relative position of each lens constituting the lens unit is thermally expanded, whereby the relative position of each lens is changed. There is a description that it is for change. However, the change in the focal length of the lens is not only due to the thermal expansion of the lens barrel, but also the change in the refractive index of each lens and the change in the shape of each curved surface of each lens due to a temperature change. However, the invention described in Patent Document 2 cannot cope with such factors.

  The present invention solves the above-described conventional problems, and corresponds to a member fixing structure that is deformed so as to change the relative position of the lens and the image sensor depending on the heat generation and operating temperature environment of the image sensor. It is an object of the present invention to provide an imaging apparatus capable of returning the position of the image to an appropriate relative positional relationship, and an image forming apparatus equipped with the imaging apparatus.

  In order to achieve the object, an invention according to claim 1 is a lens unit that forms reflected light of an image of interest, an imaging device that converts the reflected light thus formed into an electrical signal, and In an imaging apparatus including a fixing structure and a structure having a fixing structure of the imaging element, the structure is provided via an imaging element fixing member that corrects the fixing position of the imaging element according to a temperature change. With this configuration, the position of the image sensor with respect to the lens unit that changes depending on the environmental temperature can be returned to an appropriate relative positional relationship. For example, if the focal length of the lens of the lens unit hardly changes depending on the operating temperature environment, but the structure thermally expands due to an increase in the environmental temperature and extends the relative distance between the lens and the image sensor, the image sensor is fixed. Since the member is thermally deformed by the increase in the environmental temperature and deforms in a direction to bring the image sensor closer to the lens, the relative position between the lens and the image sensor is maintained.

  According to a second aspect of the present invention, in the imaging apparatus according to the first aspect, the imaging element fixing member is made of two or more kinds of materials having different linear expansion coefficients. Even if the imaging position of the lens changes due to the change, the position of the image sensor can be adjusted to the imaging position. The moving direction of the image sensor may be either, and correction in the depth direction is performed as a part thereof. As a result, it is possible to cope with correction in the vertical registration direction and the horizontal registration direction.

  According to a third aspect of the present invention, in the imaging device according to the first or second aspect, the imaging element fixing member and the structure are joined at two or more junction points or junctions arranged in the main scanning direction with respect to the imaging element. With this configuration, even if the imaging position of the lens changes due to changes in the operating temperature environment, the position of the image sensor can be adjusted to the imaging position. Do not thicken.

  According to a fourth aspect of the present invention, there is provided the imaging device according to the first or second aspect, wherein the imaging element fixing member and the structure are joined at two or more junction points or junctions arranged in the sub-scanning direction with respect to the imaging element. In this configuration, the deformation force of the image sensor fixing member can be prevented from affecting the main scanning direction of the image sensor.

  According to a fifth aspect of the present invention, in the imaging apparatus according to any one of the first to fourth aspects, the imaging element and the imaging element fixing member are joined in the vicinity of the center of the imaging element. Thus, it is difficult to transmit the force for deforming the image sensor fixing member to the image sensor, and deformation of the image sensor can be prevented.

  According to a sixth aspect of the present invention, in the imaging apparatus according to any one of the first to fourth aspects, the imaging element and the imaging element fixing member are joined in the vicinity of both ends of the imaging element. Therefore, it is possible to prevent the deformation force of the image sensor fixing member from being transmitted to the image sensor, to prevent the image sensor from being deformed, and to adjust the relative position between the image sensor and the lens unit with high accuracy.

  According to a seventh aspect of the present invention, in the imaging apparatus according to any one of the first to fourth aspects, the imaging element and the imaging element fixing member are bonded to each other with a rigidity after curing lower than that of the imaging element and the imaging element fixing member. It is characterized by being joined by an agent or an adhesive material, and this configuration makes it difficult to transmit the deformation force of the image sensor fixing member to the image sensor and prevents the image sensor from being deformed.

  According to an eighth aspect of the present invention, in the imaging device according to any one of the first to fourth aspects, the imaging element fixing member is made of a different material depending on a distance from the center of the imaging element. With this configuration, the amount of deformation of the image sensor fixing member at the part joined to the image sensor can be reduced, whereby the deformation force transmitted to the image sensor can be reduced, and further, transmission to the image sensor fixing member can be reduced. The position of the image sensor can be adjusted in consideration of the thermal time lag.

  According to a ninth aspect of the present invention, in the imaging apparatus according to any one of the first to fourth aspects, the surface area of the imaging element fixing member is asymmetric with respect to the center of the imaging element. By making the heat generation amount of the image sensor asymmetrical, it becomes possible to correct the change in the position of the image sensor due to heat transfer from the image sensor so as to be symmetric.

  According to a tenth aspect of the present invention, in the image reading unit that reads an image from a reading target and an image forming apparatus that receives information from the image reading unit and forms an image on a recording medium, the image reading unit is the first image reading unit. The image pickup apparatus described in any one of 1 to 9 is mounted, and this configuration realizes an image forming apparatus in which good image reading is stably performed and high-quality image formation is performed. .

  According to the imaging apparatus according to the present invention, the position of the imaging element with respect to the lens unit that changes depending on the environmental temperature can be returned to an appropriate relative positional relationship. For example, if the focal length of the lens of the lens unit hardly changes depending on the environmental temperature, but the structure thermally expands due to the increase of the environmental temperature and extends the relative distance between the lens and the imaging element, the imaging element fixing member However, since the thermal deformation is caused by the increase of the environmental temperature and the imaging element is deformed in a direction to approach the lens, the relative position between the lens and the imaging element is maintained. More specifically, no measures are taken against changes in the focal length due to changes in the relative position of each lens or changes in refractive index, and the relative positional relationship of the image sensor can be changed with respect to the changed focus position. It becomes possible.

  According to the image forming apparatus according to the present invention, since the image pickup apparatus according to the present invention is mounted as the image reading unit, it is possible to stably read a good image corresponding to a change in environmental temperature. An image forming apparatus that performs high-quality image formation is realized.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a perspective view showing a main part for explaining Embodiment 1 of an image pickup apparatus according to the present invention. 1 includes a condensing lens inside, and forms reflected light of a target image. The lens unit 2 is an image sensor such as a CCD that converts the reflected light imaged into an electrical signal, 3 is a plate-shaped image sensor fixing member that holds the back surface of the image sensor 2 on the plane side, and 4 is an image sensor. A substrate 5 that electrically connects the terminals of the image sensor 2 via the element fixing member 3 and is mounted with an imaging control system / driving system circuit, etc., has a plate shape and is attached to a bent portion 5a at one end. The base unit of the structure that holds and fixes the lens unit 1, the image sensor fixing member 3, the substrate 4, and the like.

  The state shown in FIG. 1 is a normal temperature state, and in use, the image pickup device 2 generates heat, and the heat is transmitted to the base body 5 and the lens unit 1 through the image pickup device fixing member 3, and after a certain period of time, The temperature is in an equilibrium state (this is the high temperature state).

  In the high temperature state, the focal position of the lens unit 1 is displaced by a change in the relative position of each lens ball in the lens unit 1 or a change in the refractive index of each lens ball. Here, this displacement amount is assumed to be δL. Further, the base body 5 also undergoes thermal deformation (thermal expansion) in a high temperature state, and the relative position between the lens unit 1 and the image sensor 2 is displaced. The amount of displacement at this time is assumed to be δK.

  In the case of δL = δK, there is no problem because the imaging device 2 matches the focal position of the lens unit 1. However, in the case of δL> δK, the focal position of the lens unit 1 is displaced to a position shifted by (δL−δK) in the direction away from the lens unit 1 from the position of the image sensor 2, and δL <δK. In this case, the focal position of the lens unit 1 is displaced to a position shifted by (δK−δL) in the direction approaching the lens unit 1 from the position of the image sensor 2.

  In the first embodiment, when δL> δK or when δL <δK, the image sensor fixing member 3 is deformed by the amount of deviation, and the focus position of the image sensor 2 and the lens unit 1 is matched to fix the image sensor. The member 3 is adapted to correct the fixed position of the image sensor 2 according to the temperature change.

  FIG. 2 is a perspective view showing a main part for explaining Embodiment 2 of the imaging apparatus according to the present invention. In the following description, members corresponding to those already described are denoted by the same reference numerals, and detailed description thereof is omitted.

Embodiment 2 is an embodiment differs from the first image sensor fixing member 7, and the member 7a of the linear expansion coefficient Z _1, is formed by a member 7b of the linear expansion coefficient Z _2, one surface of the image sensor fixing member 7 A member 7 a having a linear expansion coefficient Z ₁ is held and fixed on the horizontal extension portion 5 b of the base member 5, and the imaging element is placed on the member 7 b having a linear expansion coefficient Z ₂ , which is the other surface of the imaging element fixing member 7. This is a configuration in which one side surface of 2 is held and fixed.

  If the base body 5 is a sheet metal part and there is a bent portion or a narrowed portion in a part of the base body 5, the base body 5 is deformed in the vertical direction (Y direction in FIG. 2) during thermal deformation, and the lens unit 1 may be displaced in the Y direction. In the structure shown in FIG. 2, it is displaced downward.

Therefore, in Embodiment 2, the image sensor fixing member 7, and the member 7a of the linear expansion coefficient _{Z 1,} is formed by a member 7b of the linear expansion coefficient _{Z 2,} by setting the relation of Z 2> _{Z 1,} When the operating temperature environment increases, the image sensor 2 is lifted in the Y direction so that the vertical resist is corrected.

  FIG. 3 is a perspective view showing an imaging element fixing member for explaining Embodiment 3 of the imaging apparatus according to the present invention.

Has Embodiment 3 Embodiment 1 differs, image sensor fixing member 8, and the member 8a of the linear expansion coefficient Z _1, the linear expansion coefficient is formed by two layers of the member 8b of Z _2, image sensor fixing member 8, the member 8 a having a linear expansion coefficient Z ₁ that is one surface of the image sensor 8 is joined to the back side of the image sensor 2 to hold and fix the image sensor 2.

In the configuration of the third embodiment, when the linear expansion coefficient satisfies the relationship of Z ₁ > Z ₂ , the imaging element 2 is deformed so as to warp away from the lens unit 1. As a result, the position of the image sensor 2 is displaced in a direction away from the lens unit 1. When the relationship of Z ₁ <Z ₂ is established, the image sensor 2 is deformed so as to warp in a direction approaching the lens unit 1. As a result, the position of the image sensor 2 is displaced in a direction approaching the lens unit 1. The positional deviation between the focal position of the lens unit 1 and the image sensor 2 is adjusted according to the direction of the displacement.

  Note that the imaging element fixing member 8 may be a member in which layers having different linear expansion coefficients are tightly bonded. For example, it may be configured by screwing an aluminum sheet metal and a steel plate.

  FIG. 4 is a perspective view showing a main part for explaining Embodiment 4 of the imaging apparatus according to the present invention.

  When the image sensor fixing member 8 is arranged in the main scanning direction (X direction) with respect to the image sensor 2 as in the third embodiment shown in FIG. 3, the deformed force of the image sensor fixing member 8 is applied to the image sensor 2, There is a possibility that the image pickup device 2 is deformed similar to the image pickup device fixing member 8. When the image sensor 2 is deformed (warped) in this way, a phenomenon in which the blur condition differs between the center and both ends of the image sensor 2 appears. For example, the center of the image sensor 2 is in focus, but both ends are out of focus.

  Correspondingly, in the fourth embodiment, the image sensor fixing member 9 is arranged orthogonally (90 degrees) to the main scanning direction (X direction) of the image sensor 2, and therefore the image sensor fixing member 9. The deformation in the main scanning direction of the image pickup device 2 does not occur due to the force when the is deformed.

  In the fourth embodiment, the sub base body 10 is provided above the base body 5 so as to cover the image sensor 2, the image sensor 2 is arranged between the base body 5 and the sub base body 10, and the image sensor fixing member 9 is provided. The image pickup device 2 is held and fixed by the image pickup device fixing member 9 so as to sandwich the base body 5 and the sub base body 10.

  In the embodiment, the imaging element 2 and the imaging element fixing member 9 are joined using an adhesive or an adhesive material. As the adhesive, it is conceivable to use an ultraviolet curable adhesive, a thermosetting adhesive, or the like.

  As a joint structure in the present embodiment, the joint portion between the image sensor fixing members 3, 7, 8, 9 and the base body 5 is composed of two or more joint points arranged in the main scanning direction with respect to the image sensor 2 or By joining at the joining surface, even if the imaging position of the lens changes due to changes in the operating temperature environment, the position of the imaging device 2 can be adjusted to the imaging position, and the thickness of the entire apparatus can be reduced. Do not thicken. Further, by joining the joint portions with the image sensor fixing members 3, 7, 8, 9 at two or more joint points or joint surfaces arranged in the sub-scanning direction with respect to the image sensor 2, the image sensor The force at the time of deformation of the fixing members 3, 7, 8, 9 can be prevented from affecting the main scanning direction of the image sensor 2.

  As shown in FIG. 5, when the image sensor 2 is joined only near the center (joint portion 11), the image sensor fixing member 8 is compared to the case where the entire back side of the image sensor is joined to the image sensor fixing member. Therefore, it is difficult to apply the force at the time of deformation to the image pickup device 2, so that the image pickup device 2 can be prevented from warping like an image pickup device fixing member 8.

  In FIG. 5, the thickness of the joint portion 11 is shown to be thick for ease of explanation. However, when an adhesive or the like is used, the thickness is actually thin.

  Further, as shown in FIG. 6, if the image pickup device 2 and the image pickup device fixing member 8 are joined in the vicinity of both ends of the image pickup device 2 (joined portions 12, 12), the image pickup device fixing member 8 is deformed. This makes it difficult to transmit the force to the image sensor 2, prevents deformation of the image sensor 2, and allows the relative position between the image sensor 2 and the lens unit 1 to be adjusted with high accuracy.

  In FIG. 6, the thickness of the joint portion 12 is shown thick for ease of explanation as described above. However, when an adhesive or the like is used, the thickness is actually thin. However, it is desirable that the imaging element fixing member 8 and the imaging element 2 have such a thickness that the imaging element fixing member 8 and the imaging element 2 do not come into contact with each other due to the warp of the imaging element fixing member 8 assumed in the use temperature environment.

  Note that the image pickup device 2 and the image pickup device fixing members 3, 7, 8, and 9 are made of an adhesive or an adhesive material whose rigidity after curing is lower than that of the image pickup device 2 and the image pickup device fixing members 3, 7, 8, and 9. By joining together, it is difficult to transmit the deformation force of the image sensor fixing members 3, 7, 8, 9 to the image sensor 2, and deformation of the image sensor 2 can be prevented.

  FIG. 7 is a perspective view showing an imaging element fixing member for explaining Embodiment 5 of the imaging apparatus according to the present invention.

  In the fifth embodiment, the imaging element fixing member 13 is joined to the outer surface of the first imaging element fixing member 13a with the second imaging element fixing member 13b and the pair of third imaging element fixing members 13c. And each image pick-up element fixing member 13a-13c is comprised with a different material according to the distance from the center part of the image pick-up element 2. FIG.

Specifically, the linear expansion coefficient Z ₁ of the first image sensor fixing member 13a joined to the back surface of the image pickup device 2, it is arranged in the center of the imaging device 2 outside the first image sensor fixing member 13a that the linear expansion coefficient Z ₂ of the second image sensor fixing member 13b, and the relationship between the linear expansion coefficient Z3 of the third image sensor fixing member 13c which is connected to both side ends of the second image sensor fixing member 13b , Z ₁ ≈Z ₂ > Z ₃ .

  With such a configuration, when the use environment temperature rises, the second imaging element fixing member 13b is less deformed near the second imaging element fixing member 13b, so that almost no force is applied to the imaging element 2, and the third imaging element fixing member 13c. The vicinity is deformed, and thereby the position of the image sensor 2 is displaced. Therefore, the amount of deformation of the image sensor fixing member 13b at the portion joined to the image sensor 2 is reduced, whereby the deformation force transmitted to the image sensor 2 can be reduced, and further the transmission to the image sensor fixing member. The position of the image sensor can be adjusted in consideration of the thermal time lag.

  As the image sensor fixing members 13a to 13c, for example, a bimetal can be used. Bimetal is made by adding manganese, chromium, copper, etc. to an alloy of iron and nickel to produce two types of metal plates having different coefficients of thermal expansion and bonding them by cold rolling.

  FIG. 8 is a perspective view showing an imaging element fixing member for explaining the sixth embodiment of the imaging apparatus according to the present invention. In the sixth embodiment, the surface area of the imaging element fixing member 14 is set with respect to the center of the imaging element 2. Thus, the amount of heat generated by the image sensor 2 is asymmetric, so that the change in the position of the image sensor 2 due to heat transfer from the image sensor 2 can be corrected to be symmetric. . The imaging element fixing member 14 has the same configuration as that of the third embodiment shown in FIG. 3 and is formed of two layers of members 14a and 14b having different linear expansion coefficients.

  In the sixth embodiment, as shown in FIG. 8, a plurality of slits 15 are formed on the left side of the image sensor fixing member 14, and the left surface of the image sensor fixing member 14 has a larger surface area than the right side. I have to. By doing in this way, when the left side of the image sensor 2 has a larger calorific value than the right side, more heat is radiated from the left side of the image sensor fixing member 14 having a large surface area.

  Also, since the slit 15 is included, the rigidity of the image sensor 2 is inferior to that on the right side, so that the left side of the image sensor fixing member 14 has a larger amount of deformation due to changes in the operating temperature environment. The amount of displacement on the left side of the element 2 increases.

  Similar effects can also be obtained by making the linear expansion coefficients of the imaging element fixing members 13a to 13c in Embodiment 5 shown in FIG.

  FIG. 9 is a schematic configuration diagram of an embodiment of an image forming apparatus equipped with an imaging apparatus according to the present invention.

  The image forming apparatus shown in FIG. 9 includes an optical reading unit 21 for reading a document, an image forming unit 22 for forming an image, an automatic document feeder (ADF) 23, and a document discharge tray for stacking documents D sent from the ADF 23. 24, a paper feed unit 29 including paper feed cassettes 25 to 28 for storing various paper P as recording media, and a paper discharge tray 30 for stacking the paper P after image formation are provided.

  Then, when the document D is set on the document table 31 of the ADF 23 and an operation on an operation unit (not shown), for example, a pressing operation of the print key is performed, the uppermost document D is sent out in the direction of the arrow B1 by the rotation of the pickup roller 32. The image of the original D conveyed on the contact glass 34 of the optical reading unit 21 by the transfer of the original conveying belt 33 is optically transmitted by the optical reading unit 21 installed between the image forming unit 22 and the contact glass 34. Can be read.

  The optical reading unit 21 includes a light source 36 that illuminates the document D on the contact glass 34, an optical system 37 that includes a lens unit that forms an image of the document, and an image sensor 38 that includes a CCD that collects the document image. The image reading apparatus includes the imaging apparatus according to the embodiment of the present invention described above, and the scanning body 39 including a mirror that deflects the light beam from the light source 36 to the imaging element 38.

  After the image reading by the optical reading unit 21 is completed, the document D is transported in the direction of arrow B2 by the rotation of the document transport belt 33 and discharged onto the document discharge tray 24. Thus, the originals D are fed one by one onto the contact glass 34 and the original image is read by the optical reading unit 21.

  On the other hand, the image forming unit 22 is provided with a photoconductor 40 as an image carrier. The photoconductor 40 is driven to rotate clockwise in FIG. 9 and the surface thereof is charged to a predetermined potential by a charger 41. The Further, the optical writing unit 42 emits laser light L that is light-modulated in accordance with the image information read by the optical reading unit 21, and the surface of the photoreceptor 40 charged by the laser light L is applied to the surface. Exposure is performed to form an electrostatic latent image on the surface of the photoreceptor 40.

  The electrostatic latent image is developed with toner by the developing unit 43, and the toner image on the surface of the photoreceptor 40 is transferred to the paper P conveyed to the nip between the photoreceptor 40 and the transfer device 44. Residual toner and the like are removed from the surface of the photoreceptor 40 after the transfer of the toner image by a cleaning device 45.

  In the conveyance path of the sheet P, the sheet P selected from any of the plurality of sheet feeding cassettes 25 to 28 arranged in the lower part of the image forming unit 42 is fed in the direction of the arrow B3, as described above. The toner image formed on the surface of the photoreceptor 40 is transferred to the paper P. Next, the sheet P is passed through the fixing device 46 in the image forming unit 2 in the direction indicated by the arrow B4, and the toner image transferred to the surface of the sheet P is fixed by heating and pressing. The paper P that has undergone the fixing process in the fixing device 46 is discharged and stacked by the discharge roller pair 47 in the direction of the paper discharge tray 30 indicated by the arrow B5.

  In the image forming apparatus, by adopting the configuration of the imaging apparatus according to the embodiment of the present invention in the optical writing unit 42 that is an image reading unit including the optical system 37 including the lens unit and the imaging element 38, Good image reading is stably performed, and high-quality image formation is possible.

  The present invention is applied to an apparatus in which a lens unit and an image sensor are held and fixed, and particularly applied to an image reading unit in an image forming apparatus such as a copying machine, a facsimile machine, and a printer, or an imaging unit of a digital camera. It is valid.

The perspective view which shows the principal part for demonstrating Embodiment 1 of the imaging device which concerns on this invention The perspective view which shows the principal part for describing Embodiment 2 of the imaging device which concerns on this invention The perspective view which shows the image pick-up element fixing member for describing Embodiment 3 of the imaging device which concerns on this invention The perspective view which shows the principal part for describing Embodiment 4 of the imaging device which concerns on this invention The perspective view which shows the example of joining structure of the image pick-up element and image pick-up element fixing member in this embodiment The perspective view which shows the other joining structure example of the image pick-up element and image pick-up element fixing member in this embodiment The perspective view which shows the image pick-up element fixing member for describing Embodiment 5 of the imaging device which concerns on this invention The perspective view which shows the image pick-up element fixing member for describing Embodiment 6 of the imaging device which concerns on this invention 1 is a schematic configuration diagram of an embodiment of an image forming apparatus equipped with an imaging apparatus according to the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Lens unit 2 Image sensor 3, 7, 8, 9, 13, 14 Image sensor fixing member 4 Board | substrate 5 Base body (structure)
DESCRIPTION OF SYMBOLS 10 Sub base body 11,12 Joint part 15 Slit 21 Optical reading unit 22 Image formation part

Claims (10)

A lens unit that forms reflected light of a target image; an image pickup device that converts the formed reflected light into an electrical signal; and a structure having a fixing structure of the lens unit and a fixing structure of the image pickup device. In the imaging device
An image pickup apparatus, wherein the image pickup device is provided in the structure via an image pickup device fixing member that corrects a fixed position of the image pickup device according to a temperature change.   The imaging apparatus according to claim 1, wherein the imaging element fixing member is made of two or more kinds of materials having different linear expansion coefficients.   The said image pick-up element fixing member and the said structure are joined to the said image pick-up element by two or more joining points or joint surfaces arrange | positioned in the main scanning direction. Imaging device.   The said image pick-up element fixing member and the said structure are joined to the said image pick-up element by the joint point or joint surface of two or more places arrange | positioned with respect to the subscanning direction. Imaging device.   The image pickup apparatus according to claim 1, wherein the image pickup element and the image pickup element fixing member are joined in the vicinity of a center portion of the image pickup element.   The imaging apparatus according to claim 1, wherein the imaging element and the imaging element fixing member are joined in the vicinity of both ends of the imaging element.   The image pickup device and the image pickup device fixing member are bonded to each other by an adhesive or an adhesive material whose rigidity after curing is lower than that of the image pickup device and the image pickup device fixing member. The imaging device according to item.   The imaging apparatus according to claim 1, wherein the imaging element fixing member is made of a different material depending on a distance from a center portion of the imaging element.   The imaging apparatus according to claim 1, wherein a surface area of the imaging element fixing member is asymmetric with respect to a center of the imaging element.   An image reading unit that reads an image from a reading target and an image forming apparatus that receives information from the image reading unit and forms an image on a recording medium, wherein the image reading unit is described in any one of claims 1 to 9. An image forming apparatus having the image pickup apparatus mounted thereon.

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