JP2006244888A - Electro-optical device, its manufacturing method, image printer and image reader - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electro-optical device capable of making the area of a substrate small, and which can be manufactured simply and accurately. <P>SOLUTION: The electro-optical device is provided with an electro-optical panel 10, wherein a plurality of EL elements 16 in which light emission characteristics change with provided electrical energy are arranged, an IC element 18 electrically connected with the electro-optical panel 10 and having a circuit drive or controlling the EL element 16 inside, and a FPC20 mounting the IC element 18 and provided with wiring electrically connected with a circuit in the IC element 18. The IC element 18 has a plurality of first terminal pads 30, connected with the wiring on the FPC20 and a plurality of second terminal pads 32 connected with the wiring on the electro-optical panel 10. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an electro-optical device having an electro-optical panel in which light-emitting elements or light valve elements are arranged, a manufacturing method thereof, an image printing apparatus, and an image reading apparatus.

  A light-emitting element or a light valve element, that is, an electro-optical panel in which electro-optical elements are arranged is widely used as an image display device. Such an electro-optical panel is also used as a light emitting device for writing an electrostatic latent image on an image carrier (for example, a photosensitive drum) of an electrophotographic image printing apparatus. Each of these electro-optical panels is connected to other circuits for driving or controlling the electro-optical element in various ways as follows.

  FIG. 1 is a side view of a conventional electro-optical device. As shown in FIG. 1, the electro-optical device includes an electro-optical panel having a main substrate 12 and a sealing body 14. This electro-optical panel is an electroluminescent (hereinafter abbreviated as “EL”) panel, and has a large number of EL elements 16 formed on the main substrate 12. The sealing body 14 is attached on the main substrate 12 and protects the EL element 16 from the outside air in cooperation with the main substrate 12.

  An integrated circuit (IC) element 18 is mounted on the main substrate 12 of the electro-optical panel by a COG (chip on glass) method. The IC element 18 has a circuit for driving or controlling the EL element 16 therein. For example, one IC element 18 is a scanning line driving circuit, and the other one IC element 18 is a data line driving circuit. A flexible printed circuit board (FPC) 20 is mounted on the main board 12. Although not shown, a power line connected to an external power supply circuit and a signal line connected to an external signal supply circuit are formed on the upper surface or the lower surface of the FPC 20. Electric power is supplied to the IC element 18 through a power line on the FPC 20, and a signal is supplied through a signal line on the FPC 20.

  However, in the COG method of FIG. 1, a region for mounting the IC element 18 is required in addition to the region for connecting the FPC 20 to the edge of the main substrate 12. In addition, on the edge of the main substrate 12, wiring regions connected to the IC element 18 are necessary on both sides of the IC element 18. For this reason, it is difficult to reduce the size of the electro-optical panel. Further, since the area of the expensive main substrate cannot be reduced, the manufacturing cost of the electro-optical panel is high. An apparatus similar to the electro-optical apparatus in FIG. 1 is disclosed in, for example, Patent Document 1 and Patent Document 2.

  FIG. 2 is a side view of another conventional electro-optical device. In this electro-optical device, the IC element 18 is mounted on the FPC 20 by the COF (chip on film) method, not the main substrate 12 of the electro-optical panel. In FIG. 2, reference numeral 22 denotes a COF assembly in which the IC element 18 is mounted on the FPC 20.

  FIG. 3 is a bottom view of the FPC 20 of FIG. The FPC 20 includes a primary wiring 24 that connects the IC element 18 on the FPC 20 to an external device, and a secondary wiring that is attached to the main board 12 and connects the IC element 18 to a number of EL elements 16 on the main board 12. 26 is formed. The primary wiring 24 includes a power supply line connected to an external power supply circuit and a signal line connected to an external signal supply circuit. The secondary wiring 26 includes a scanning line or a data line.

JP 2000-58255 A JP 2001-130048 A

  In the COF method of FIGS. 2 and 3, since the IC element 18 is not mounted on the main board 12, the width W of the main board 12 can be reduced. However, in either the COG method or the COF method, the pitch P between the secondary wirings 26 may be inevitably increased at the connection portion between the FPC 20 and the main substrate 12 as shown in FIG. As a method for easily connecting the FPC 20 and the main substrate 12, there is a method of bonding with an anisotropic conductive adhesive, but when using an anisotropic conductive adhesive, it is necessary to heat the binder. For this reason, the FPC 20 is also heated. For example, first, the FPC 20 is heated, and the anisotropic conductive adhesive is heated from the FPC 20 by heat conduction. Since the FPC 20 is formed of a material having a high coefficient of thermal expansion, such as a polyimide film, the pitch P between the secondary wirings 26 on the FPC is easily stretched by heat. Therefore, if the pitch P is reduced, the FPC 20 and the main board 12 are reduced. It becomes difficult to accurately connect the wiring on the FPC 20 to the wiring on the main board 12 when connecting the two.

  The pitch P between the secondary wirings 26 is required to be at least about 50 μm according to the bonding operation using a normal anisotropic conductive adhesive. Therefore, although the width W of the main board 12 can be reduced, the depth L of the main board 12 may have to be increased.

  Therefore, the present invention can reduce the area of the substrate and can easily manufacture an accurate electro-optical device, a manufacturing method for efficiently manufacturing the electro-optical device, and an image using the electro-optical device. A printing apparatus and an image reading apparatus are provided.

  The electro-optical device according to the present invention is electrically connected to an electro-optical panel in which a plurality of electro-optical elements whose light emission characteristics or light transmission characteristics are changed by applied electric energy, and the electro-optical panel, An integrated circuit element having a circuit for driving or controlling the electro-optic element therein, and a flexible circuit in which the integrated circuit element is mounted and wiring electrically connected to a circuit inside the integrated circuit element is provided. A printed circuit board. The integrated circuit element includes a plurality of first terminal pads connected to wirings on the flexible printed circuit board and a plurality of second terminal pads connected to wirings on the electro-optical panel.

  Here, the “electro-optical element” means an element whose optical characteristics (light emission characteristics or light transmission characteristics) are changed by given electrical energy. As an element whose optical characteristics are changed by electric energy, a light emitting element (for example, an electroluminescent light emitting element or a plasma display element) that converts electric energy into optical energy and a light transmittance by electric energy. There are light valve pixels that change (eg, liquid crystal pixels, electrophoretic display pixels). An “electro-optical panel” is a panel provided with an array of electro-optical elements. The electro-optical panel may be an image display panel or a light emitting panel. For example, an exposure apparatus for writing an electrostatic latent image on an image carrier (for example, a photosensitive drum) of an electrophotographic image printing apparatus may be used.

  According to the present invention, the integrated circuit element is connected to the flexible printed circuit board through its own first terminal pad, and is connected to the electro-optical panel through its own second terminal pad. Therefore, an area to which the second terminal pad of the integrated circuit element is electrically connected is necessary at the edge of the electro-optical panel. However, the first terminal pad of the integrated circuit element and the wiring connected thereto are arranged. The area to be bonded and the area to which the flexible printed circuit board is bonded are not required in the electro-optical panel. Accordingly, the width W of the electro-optical panel can be reduced as compared with the conventional technique of FIG.

  In addition, since the integrated circuit element provided with the second terminal pads connected to the wiring on the electro-optical panel has a smaller coefficient of thermal expansion than the flexible printed circuit board, the pitch between the second terminal pads of the integrated circuit elements. Is difficult to stretch even in the process of heating the anisotropic conductive adhesive. Therefore, even when the pitch between the second terminal pads is reduced, it is a conventional technique to accurately connect the second terminal pads to the wiring on the electro-optical panel when connecting the integrated circuit element and the electro-optical panel. It is easy compared. Accordingly, the depth L of the electro-optical panel can be reduced as compared with the conventional technique.

  The method of manufacturing the electro-optical device according to the present invention includes the step of arranging the integrated circuit element on the flexible printed circuit board so that the first terminal pad of the integrated circuit element is placed on the wiring on the flexible printed circuit board. And disposing the integrated circuit element on the electro-optical panel so that the second terminal pad of the integrated circuit element is placed on the wiring on the electro-optical panel. In this method, the step of disposing the integrated circuit element on the flexible printed circuit board and the electro-optical panel can be performed at an extremely close time, so that the electro-optical device can be efficiently manufactured.

  More preferably, in the step of disposing the integrated circuit element on the flexible printed circuit board, an anisotropic conductive adhesive is interposed between the first terminal pad of the integrated circuit element and the wiring on the flexible printed circuit board. In the step of disposing the integrated circuit element on the electro-optical panel, an anisotropic conductive adhesive is interposed between the second terminal pad of the integrated circuit element and the wiring on the electro-optical panel, With these anisotropic conductive adhesives, the first terminal pad and the wiring on the flexible printed circuit board, and the second terminal pad and the wiring on the electro-optical panel are bonded simultaneously. Thereby, it is possible to adhere | attach the required location with an anisotropic conductive adhesive simultaneously.

  The image printing apparatus according to the present invention irradiates a charged surface of the image carrier with the image carrier, a charger for charging the image carrier, and light emitted from the electro-optical panel. An electro-optical device of the present invention for forming an image, a developing unit for forming a visible image on the image carrier by attaching toner to the latent image, and transferring the visible image from the image carrier to another object A transfer device. By using the electro-optical device of the present invention, this image printing device can also be reduced in size.

  An image reading apparatus according to the present invention includes the electro-optical device according to the present invention and a light-receiving device that converts light emitted from the electro-optical panel and reflected by a reading target into an electric signal. By using the electro-optical device of the present invention, this image reading device can also be reduced in size.

  Hereinafter, various embodiments according to the present invention will be described with reference to the accompanying drawings. In the drawings, the ratio of dimensions of each part is appropriately changed from the actual one.

<First Embodiment>
FIG. 4 is a side view illustrating the outline of the electro-optical device according to the first embodiment of the invention. As shown in FIG. 4, the electro-optical device includes an electro-optical panel 10 having a main substrate 12 and a sealing body 14. This electro-optical panel 10 is an EL panel for image display, and has a large number of EL elements 16 formed on a main substrate 12. Here, the EL element 16 may be an organic EL element or an inorganic EL element. The sealing body 14 is adhered to the main substrate 12 with an adhesive, and protects the EL element 16 from the outside air in cooperation with the main substrate 12.

  A COF assembly 22 is mounted on the edge of the main substrate 12 of the electro-optical panel 10. The COF assembly 22 includes an FPC 20 and an IC element 18 mounted thereon. The IC element 18 has a circuit for driving or controlling the EL element 16 therein. For example, one IC element 18 is a scanning line driving circuit, and the other one IC element 18 is a data line driving circuit. The FPC 20 is formed of, for example, a polyimide film and is not shown in FIG. 4, but a power line connected to an external power circuit and a signal line connected to an external signal supply circuit are formed on the upper surface of the FPC 20. . Electric power is supplied to the IC element 18 through a power line on the FPC 20, and a signal is supplied through a signal line on the FPC 20.

  In the COF assembly 22, the IC element 18 is attached to the edge of the FPC 20. FIG. 5 is an enlarged view of the portion A of FIG. The part B in FIG. 4 has the same configuration although the direction is reversed.

  FIG. 6 is a bottom view of the FPC 20. As shown in FIG. 6, the FPC 20 is formed with a primary wiring 44 for connecting the IC element 18 on the FPC 20 to an external device. On the other hand, on the main substrate 12 of the electro-optical panel 10, secondary wirings 46 that are connected to the IC elements 18 and drive a number of EL elements 16 on the main substrate 12 are formed. The primary wiring 44 includes a power supply line connected to an external power supply circuit and a signal line connected to an external signal supply circuit. The secondary wiring 46 includes a scanning line or a data line.

  As shown in FIGS. 5 and 6, the IC element 18 is provided with a plurality of terminal pads 30 and 32 protruding downward from the lower surface thereof. Of the terminal pads 30 and 32, the first terminal pad 30 is connected to the primary wiring 44 on the FPC 20, and the second connection wiring 46 is connected to the secondary wiring 46 on the main substrate 12 of the electro-optical panel 10. 2 terminal pads 32. The second terminal pad 32 extends longer than the first terminal pad 30 and is passed through a through-hole 34 formed at the edge of the FPC 20. However, the second terminal pads 32 are electrically connected to the main board 12 and are not electrically connected to the FPC 20.

  The end faces of the terminal pads 30 and 32 are bonded to the FPC 20 or the main board 12 with an anisotropic conductive adhesive 38. The anisotropic conductive adhesive 38 may be an anisotropic conductive film (ACF) or an anisotropic conductive paste (ACP). When the anisotropic conductive paste is used, the anisotropic conductive paste has a high fluidity before curing. Therefore, the FPC 20 and the main substrate 12 have fluidity at the portion where the terminal pads 30 and 32 are joined. In order to keep a certain anisotropic conductive paste, it is preferable to form a bank in advance.

  As another form, if an electrical connection at a required position can be obtained, the end surfaces of the terminal pads 30 and 32 are placed on the wiring of the FPC 20 and the main board 12 without using the anisotropic conductive adhesive 38. You can just place it on the required position.

  Next, a method for manufacturing the electro-optical device will be described. First, as shown in FIG. 7, an IC element 18 having terminal pads 30 and 32 is prepared. Further, an FPC 20 having a power supply line and a signal line (primary wiring 44 in FIG. 6) and having a through hole 34 is prepared.

  Next, as shown in FIG. 8, the second terminal pad 32 is passed through the through hole 34 of the FPC 20, and the first terminal pad 30 is placed on the power line and the signal line on the FPC 20 to be electrically connected. The IC element 18 is placed on the FPC 20 to form the COF assembly 22. Further, as shown in FIG. 5, the second terminal pads 32 are placed on the data lines and scanning lines (secondary wiring 46 in FIG. 6) on the main substrate 12 of the electro-optical panel 10 so as to be electrically connected. The IC element 18 is disposed on the main substrate 12. In this method, the step of placing the IC element 18 on the FPC 20 and the electro-optical panel 10 can be performed at an extremely close time, and therefore the electro-optical device 10 can be efficiently manufactured.

  When the anisotropic conductive adhesive 38 is used to mechanically fix the terminal pads 30 and 32 at predetermined positions, in the step of disposing the IC element 18 on the FPC 20 (FIG. 8), the first step of the IC element 18 is performed. An anisotropic conductive adhesive 38 is interposed between one terminal pad 30 and the primary wiring on the FPC 20. Further, in the step of disposing the IC element 18 on the main substrate 12 of the electro-optical panel 10 (FIG. 5), anisotropy is provided between the second terminal pad 32 of the IC element 18 and the secondary wiring on the main substrate 12. A conductive adhesive 38 is interposed.

  The anisotropic conductive adhesive 38 is heated and pressed to be pressed or cured at a predetermined position. The FPC 20 and the main substrate 12 of the electro-optical panel 10 are pressed against the IC element 18 at different times, and the first terminal pad 30 of the IC element 18 and the FPC 20 are pressed by the anisotropic conductive adhesive 38; The crimping of the second terminal pad 32 of the IC element 18 and the main substrate 12 by the anisotropic conductive adhesive 38 may be performed at another time. However, the FPC 20 and the main substrate 12 of the electro-optical panel 10 are pressed against the IC element 18 at the same time, and the first terminal pad 30 of the IC element 18 and the FPC 20 are bonded by the anisotropic conductive adhesive 38, and the IC It is preferable to simultaneously press the second terminal pad 32 of the element 18 and the main substrate 12 with the anisotropic conductive adhesive 38. As a result, it is possible to simultaneously bond the necessary portions with the anisotropic conductive adhesive 38.

  According to this embodiment, the IC element 18 is connected to the FPC 20 via its own first terminal pad 30 and connected to the main substrate 12 of the electro-optical panel 10 via its own second terminal pad 32. Is done. Therefore, an area to which the second terminal pad 32 of the IC element 18 is electrically connected is necessary at the edge of the main substrate 12 of the electro-optical panel 10, but the first terminal pad 30 of the IC element 18 and the like A region for arranging the wiring connected thereto and a region for bonding the FPC 20 are not required in the electro-optical panel 10. Therefore, the width W of the electro-optical panel 10 can be reduced as compared with the conventional technique of FIG.

  Further, since the IC element 18 provided with the second terminal pads 32 connected to the wiring on the electro-optical panel 10 has a smaller coefficient of thermal expansion than the FPC 20, the second terminal pads 32 of the IC element 18 are not connected to each other. The pitch is difficult to stretch even in the process of heating the anisotropic conductive adhesive 38. Therefore, even when the pitch between the second terminal pads 38 is reduced, the second terminal pad 32 is accurately connected to the wiring on the electro-optical panel 10 when the IC element 18 and the electro-optical panel 10 are connected. Is easier than the prior art. Therefore, the depth L of the electro-optical panel 10 can also be reduced as compared with the conventional technique.

<Second Embodiment>
FIG. 9 is a side view showing an outline of an electro-optical device according to the second embodiment of the invention. In the drawings relating to the second embodiment, the same reference numerals are used to indicate the same components as those in the first embodiment, and detailed description thereof will not be given.

  The difference between the second embodiment and the first embodiment is the arrangement of the terminal pads 30 and 32 in the IC element 18. Specifically, in the second embodiment, since the first terminal pad 30 is provided only on one end side of the IC element 18, the first terminal pad 30 is easily connected to the FPC 20. Since the longer second terminal pad 32 is provided only on the other end side of the IC element 18, it can be easily connected to the main substrate 12 of the electro-optical panel 10. Therefore, the through hole 34 is not formed in the FPC 20.

  Next, a method for manufacturing the electro-optical device will be described. First, as shown in FIG. 10, an IC element 18 having terminal pads 30 and 32 is prepared. Further, the FPC 20 provided with the power supply line and the signal line (the primary wiring 44 in FIG. 6) is prepared.

  Next, as shown in FIG. 11, the IC element 18 is disposed on the FPC 20 so that the first terminal pad 30 is placed on the power line and the signal line on the FPC 20 to be electrically connected, thereby forming the COF assembly 22. To do. Further, as shown in FIG. 9, the second terminal pads 32 are placed on the data lines and the scanning lines (secondary wiring in FIG. 6) on the main substrate 12 of the electro-optical panel 10 so as to be electrically connected. The IC element 18 is disposed on the main substrate 12. However, the step of connecting the IC element 18 to the main substrate 12 may be performed before the step of connecting the IC element 18 to the FPC 20. In any of these methods, the step of placing the IC element 18 on the FPC 20 and the electro-optical panel 10 can be performed at a very close time, and thus the electro-optical device 10 can be efficiently manufactured. It is.

  When the anisotropic conductive adhesive 38 is used to mechanically fix the terminal pads 30 and 32 at predetermined positions, in the step of disposing the IC element 18 on the FPC 20 (FIG. 10), the first step of the IC element 18 is performed. An anisotropic conductive adhesive 38 is interposed between one terminal pad 30 and the primary wiring on the FPC 20. Further, in the step of disposing the IC element 18 on the main substrate 12 of the electro-optical panel 10 (FIG. 9), the anisotropy is provided between the second terminal pad 32 of the IC element 18 and the secondary wiring on the main substrate 12. A conductive adhesive 38 is interposed.

  The anisotropic conductive adhesive 38 is heated and pressed to be pressed or cured at a predetermined position. The FPC 20 and the main substrate 12 of the electro-optical panel 10 are pressed against the IC element 18 at different times, and the first terminal pad 30 of the IC element 18 and the FPC 20 are pressed by the anisotropic conductive adhesive 38; The crimping of the second terminal pad 32 of the IC element 18 and the main substrate 12 by the anisotropic conductive adhesive 38 may be performed at another time. However, the FPC 20 and the main substrate 12 of the electro-optical panel 10 are pressed against the IC element 18 at the same time, and the first terminal pad 30 of the IC element 18 and the FPC 20 are bonded by the anisotropic conductive adhesive 38, and the IC It is preferable to simultaneously press the second terminal pad 32 of the element 18 and the main substrate 12 with the anisotropic conductive adhesive 38. As a result, it is possible to simultaneously bond the necessary portions with the anisotropic conductive adhesive 38.

  The electro-optical device according to this embodiment can also achieve the same effect as that of the first embodiment.

<Modification>
As described above, the electro-optical device having the EL panel for image display as the electro-optical panel 10 has been described as the embodiment of the present invention. However, the above-described features can be applied to electro-optical devices having other electro-optical panels. Good. For example, the electro-optical panel of the electro-optical device according to the present invention may not be for image display, but may be an electro-optical panel for various exposures or an electro-optical panel for illumination. In addition, the electro-optical panel of the electro-optical device according to the invention is not limited to an EL panel, and may be a light-emitting panel (for example, a plasma light-emitting panel) in which other types of light-emitting elements are arranged, or depending on applied electric energy. It may be a light valve panel in which a large number of light valve pixels whose light transmittance changes are arranged, for example, a liquid crystal panel or an electrophoretic light valve panel.

  In the above-described embodiment, the IC element 18 includes a scanning line driving circuit and a data line driving circuit for driving the electro-optical element for image display, respectively, but other types of driving circuits for exposure or illumination are used. It may be built in. Further, the IC element 18 may incorporate another type of circuit that controls the electro-optical element. The number of IC elements 18 is not particularly limited.

<Image printing device>
The electro-optical panel of the electro-optical device according to the modification can be used as a line-type optical head for writing a latent image on an image carrier in an image printing apparatus using an electrophotographic system. Examples of the image printing apparatus include a printer, a printing part of a copying machine, and a printing part of a facsimile.

  FIG. 12 is a longitudinal sectional view showing an example of an image printing apparatus using the electro-optical panel of the electro-optical device according to the above modification as a line type optical head. This image printing apparatus is a tandem type full-color image printing apparatus using a belt intermediate transfer body system.

  In this image printing apparatus, four organic EL array exposure heads 10K, 10C, 10M, and 10Y having the same configuration are replaced with four photosensitive drums (image carriers) 110K, 110C, 110M, and 110Y having the same configuration. The exposure positions are respectively arranged. The organic EL array exposure heads 10K, 10C, 10M, and 10Y are electro-optical panels of the above-described electro-optical device.

  As shown in FIG. 12, this image printing apparatus is provided with a driving roller 121 and a driven roller 122, and an endless intermediate transfer belt 120 is wound around these rollers 121 and 122, as indicated by arrows. Thus, the periphery of the rollers 121 and 122 is rotated. Although not shown, tension applying means such as a tension roller that applies tension to the intermediate transfer belt 120 may be provided.

  Around the intermediate transfer belt 120, photosensitive drums 110K, 110C, 110M, and 110Y having photosensitive layers on four outer peripheral surfaces are arranged at predetermined intervals. The subscripts K, C, M, and Y mean that they are used to form black, cyan, magenta, and yellow visible images, respectively. The same applies to other members. The photosensitive drums 110K, 110C, 110M, and 110Y are rotationally driven in synchronization with the driving of the intermediate transfer belt 120.

  Around each photosensitive drum 110 (K, C, M, Y), a corona charger 111 (K, C, M, Y), an organic EL array exposure head 10 (K, C, M, Y), and Developers 114 (K, C, M, Y) are disposed. The corona charger 111 (K, C, M, Y) uniformly charges the outer peripheral surface of the corresponding photosensitive drum 110 (K, C, M, Y). The organic EL array exposure head 10 (K, C, M, Y) writes an electrostatic latent image on the charged outer peripheral surface of the photosensitive drum. In each organic EL array exposure head 10 (K, C, M, Y), the arrangement direction of the plurality of EL elements 16 is aligned with the bus (main scanning direction) of the photosensitive drum 110 (K, C, M, Y). Installed. The electrostatic latent image is written by irradiating the photosensitive drum with light by the plurality of EL elements 16 described above. The developing device 114 (K, C, M, Y) forms a visible image, that is, a visible image on the photosensitive drum by attaching toner as a developer to the electrostatic latent image.

  The black, cyan, magenta, and yellow developed images formed by the four-color single-color image forming station are sequentially transferred onto the intermediate transfer belt 120 to be superimposed on the intermediate transfer belt 120. As a result, a full-color visible image is obtained. Four primary transfer corotrons (transfer devices) 112 (K, C, M, Y) are arranged inside the intermediate transfer belt 120. The primary transfer corotron 112 (K, C, M, Y) is disposed in the vicinity of the photosensitive drum 110 (K, C, M, Y), and the photosensitive drum 110 (K, C, M, Y). The electrostatic image is electrostatically attracted from the toner image to transfer the visible image to the intermediate transfer belt 120 passing between the photosensitive drum and the primary transfer corotron.

  A sheet 102 as an object on which an image is to be finally formed is fed one by one from the sheet feeding cassette 101 by the pickup roller 103, and between the intermediate transfer belt 120 and the secondary transfer roller 126 in contact with the driving roller 121. Sent to the nip. The full-color visible image on the intermediate transfer belt 120 is secondarily transferred to one side of the sheet 102 by the secondary transfer roller 126 and fixed on the sheet 102 through the fixing roller pair 127 as a fixing unit. . Thereafter, the sheet 102 is discharged onto a paper discharge cassette formed in the upper part of the apparatus by a paper discharge roller pair 128.

  Since the image printing apparatus of FIG. 12 uses the electro-optical device of the above modification as writing means, the apparatus can be made smaller than when the laser scanning optical system is used. Further, as described above, the electro-optical device according to the modified example can be made smaller than the conventional one, so that the electro-optical device can be disposed at a position close to the photosensitive drums 110K, 110C, 110M, and 110Y, and the image printing apparatus is also more. It is possible to reduce the size.

Next, another modification of the image printing apparatus according to the present invention will be described.
FIG. 13 is a longitudinal sectional view of another image printing apparatus using the electro-optical panel of the electro-optical device according to the above modification as a line type optical head. This image printing apparatus is a rotary development type full-color image printing apparatus using a belt intermediate transfer body system. In the image printing apparatus shown in FIG. 13, a corona charger 168, a rotary developing unit 161, an organic EL array exposure head 167, and an intermediate transfer belt 169 are provided around a photosensitive drum (image carrier) 165. Yes.

  The corona charger 168 uniformly charges the outer peripheral surface of the photosensitive drum 165. The organic EL array exposure head 167 writes an electrostatic latent image on the charged outer peripheral surface of the photosensitive drum 165. The organic EL array exposure head 167 is the electro-optical device of the above-described modification, and is installed so that the arrangement direction of the plurality of EL elements 16 is along the bus line (main scanning direction) of the photosensitive drum 165. The electrostatic latent image is written by irradiating the photosensitive drum with light by the plurality of EL elements 16 described above.

  The developing unit 161 is a drum in which four developing units 163Y, 163C, 163M, and 163K are arranged at an angular interval of 90 °, and can rotate counterclockwise about the shaft 161a. The developing units 163Y, 163C, 163M, and 163K supply yellow, cyan, magenta, and black toners to the photosensitive drum 165, respectively, and attach the toner as a developer to the electrostatic latent image, thereby the photosensitive drum 165. A visible image, that is, a visible image is formed.

  The endless intermediate transfer belt 169 is wound around a driving roller 170a, a driven roller 170b, a primary transfer roller 166, and a tension roller, and is rotated around these rollers in a direction indicated by an arrow. The primary transfer roller 166 transfers the visible image to the intermediate transfer belt 169 that passes between the photosensitive drum and the primary transfer roller 166 by electrostatically attracting the visible image from the photosensitive drum 165.

  Specifically, in the first rotation of the photosensitive drum 165, an electrostatic latent image for a yellow (Y) image is written by the exposure head 167, and a developed image of the same color is formed by the developing unit 163Y. The image is transferred to the transfer belt 169. Further, in the next rotation, an electrostatic latent image for a cyan (C) image is written by the exposure head 167, and a developed image of the same color is formed by the developing device 163C. The intermediate transfer is performed so as to overlap the yellow developed image. Transferred to the belt 169. Then, during the four rotations of the photosensitive drum 9, the yellow, cyan, magenta, and black visible images are sequentially superimposed on the intermediate transfer belt 169. As a result, a full-color visible image is formed on the transfer belt 169. It is formed. When images are finally formed on both sides of a sheet as an object on which an image is to be formed, the same color images of the front and back surfaces are transferred to the intermediate transfer belt 169, and then the front and back surfaces are transferred to the intermediate transfer belt 169. A full-color visible image is obtained on the intermediate transfer belt 169 by transferring the visible image of the next color.

  The image printing apparatus is provided with a sheet conveyance path 174 through which a sheet is passed. The sheets are picked up one by one from the paper feed cassette 178 by the pick-up roller 179, advanced through the sheet transport path 174 by the transport roller, and between the intermediate transfer belt 169 and the secondary transfer roller 171 in contact with the drive roller 170a. Pass through the nip. The secondary transfer roller 171 transfers the developed image to one side of the sheet by electrostatically attracting a full-color developed image from the intermediate transfer belt 169 collectively. The secondary transfer roller 171 can be moved closer to and away from the intermediate transfer belt 169 by a clutch (not shown). The secondary transfer roller 171 is brought into contact with the intermediate transfer belt 169 when a full-color visible image is transferred onto the sheet, and is separated from the secondary transfer roller 171 while the visible image is superimposed on the intermediate transfer belt 169.

  The sheet on which the image has been transferred as described above is conveyed to the fixing device 172 and is passed between the heating roller 172a and the pressure roller 172b of the fixing device 172, whereby the visible image on the sheet is fixed. The sheet after the fixing process is drawn into the discharge roller pair 176 and proceeds in the direction of arrow F. In the case of double-sided printing, after most of the sheet passes through the paper discharge roller pair 176, the paper discharge roller pair 176 is rotated in the reverse direction and introduced into the double-sided printing conveyance path 175 as indicated by an arrow G. The Then, the visible image is transferred to the other surface of the sheet by the secondary transfer roller 171, the fixing process is performed again by the fixing device 172, and then the sheet is discharged by the discharge roller pair 176.

  Since the image printing apparatus of FIG. 13 uses the exposure head 167 (electro-optical panel of the electro-optical device of the above-described modification) having an organic EL array as writing means, than the case of using a laser scanning optical system, The size of the apparatus can be reduced. Further, as described above, since the electro-optical device can be made smaller than before, the electro-optical device can be arranged at a position close to the photosensitive drum 165, and the image printing apparatus can be further reduced in size.

  As described above, the image printing apparatus to which the electro-optical device of the above-described modification can be applied has been exemplified. However, the electro-optical device of the above-described modification can be applied to other electrophotographic image printing apparatuses, Such an image printing apparatus is within the scope of the present invention. For example, the electro-optical device of the above modification is applied to an image printing apparatus that transfers a visible image directly from a photosensitive drum to a sheet without using an intermediate transfer belt, and an image printing apparatus that forms a monochrome image. Is possible.

<Image reading device>
Further, the electro-optical device according to the above-described modification can be used as a line-type optical head for irradiating light to a reading target in the image reading device. Examples of the image reading apparatus include a scanner, a reading portion of a copying machine, a reading portion of a facsimile, a barcode reader, and a two-dimensional image code reader that reads a two-dimensional image code such as a QR code (registered trademark).

  FIG. 14 is a longitudinal sectional view showing an example of an image reading apparatus using the electro-optical device according to the above modification as a line type optical head. A flat platen glass 202 is provided on the upper part of the cabinet 201 of the image reading apparatus, and a document 203 is placed on the platen glass 202 with its image surface facing downward. A platen cover (not shown) presses the document 203 toward the platen glass 202.

Inside the cabinet 201, a high speed carriage 204 and a low speed carriage 205 are arranged so as to be movable in the horizontal direction. An organic EL array exposure head 206 that irradiates the original 203 and a reflecting mirror 207 are mounted on the high-speed carriage 204, and two reflecting mirrors 208 and 209 are mounted on the low-speed carriage 205. These organic EL array exposure head 206 and reflecting mirrors 207, 208, and 209 extend in the direction perpendicular to the paper surface (main scanning direction) in FIG. The organic EL array exposure head 206 is installed so that the arrangement direction of the plurality of EL elements 16 is along the main scanning direction.

  A document reader 210 is disposed at a fixed position inside the cabinet 201. The document reader 210 includes an imaging lens 212 and a line sensor (light receiving device) 213 composed of a large number of photosensitive pixels (charge coupled devices). The line sensor 213 extends in the direction perpendicular to the paper surface (main scanning direction) in FIG. 14, and is arranged so that the arrangement direction of the plurality of photosensitive pixels is along the main scanning direction.

  Light emitted from the organic EL array exposure head 206 passes through the platen glass 202 and is reflected by the lower surface of the document 203. Reflected light from the original 203 is transmitted through the platen glass 202, reflected by the reflecting mirrors 207 to 209, and then imaged by the line sensor 213 by the imaging lens 212. The high-speed carriage 204 moves in the horizontal direction so that the entire surface of the original 203 is irradiated by the organic EL array exposure head 206, and the low-speed carriage 205 moves at half the speed of the high-speed carriage 204 to The length of the reflected light path reaching 213 is kept constant.

  The image reading apparatus to which the electro-optical device according to the above-described modification can be applied has been described above. However, the electro-optical device according to the above-described modification can be applied to other image reading devices. Printing devices are within the scope of the present invention. For example, the light receiving device may move together with the electro-optical device as the illumination device, or both the light receiving device and the electro-optical device may be fixed and the original or the reading target may be moved and read.

It is a side view of a conventional electro-optical device. It is a side view of another conventional electro-optical device. FIG. 3 is a bottom view of the FPC of the electro-optical device in FIG. 2. 1 is a side view illustrating an outline of an electro-optical device according to a first embodiment of the invention. It is an enlarged view of the part A of FIG. FIG. 6 is a bottom view of the FPC of the electro-optical device in FIG. 5. FIG. 5 is a diagram illustrating a step of the method for manufacturing the electro-optical device according to the first embodiment of the invention. It is a figure which shows the next process of FIG. FIG. 5 is a side view illustrating an outline of an electro-optical device according to a second embodiment of the invention. It is a figure which shows 1 process of the manufacturing method of the electro-optical apparatus which concerns on the 2nd Embodiment of this invention. FIG. 11 is a diagram showing a step subsequent to FIG. 10. FIG. 10 is a longitudinal sectional view illustrating an example of an image printing apparatus using an electro-optical panel of a modified electro-optical device according to the present invention as a line-type optical head. FIG. 10 is a longitudinal sectional view showing another example of an image printing apparatus using an electro-optical panel of a modified electro-optical device of the present invention as a line-type optical head. FIG. 10 is a longitudinal sectional view illustrating an example of an image reading apparatus using an electro-optical device according to a modification of the present invention as a line-type optical head.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Electro-optical panel, 12 ... Main board | substrate, 14 ... Sealing body, 16 ... EL element (electroluminescent element, electro-optical element), 18 ... IC element (integrated circuit element), 20 ... FPC (flexible printed circuit board) , 22 ... COF (chip on film) assembly, 24 ... primary wiring, 26 ... secondary wiring, 30 ... first terminal pad, 32 ... second terminal pad, 34 ... through hole, 38 ... anisotropic conductive bonding Agent, 44 ... primary wiring, 46 ... secondary wiring.

Claims (5)

An electro-optical panel in which a plurality of electro-optical elements whose light emission characteristics or light transmission characteristics are changed by given electric energy are arranged;
An integrated circuit element that is electrically connected to the electro-optic panel and has a circuit that drives or controls the electro-optic element;
The integrated circuit element is mounted, and includes a flexible printed circuit board provided with wiring electrically connected to a circuit inside the integrated circuit element,
The integrated circuit element includes a plurality of first terminal pads connected to wiring on the flexible printed circuit board and a plurality of second terminal pads connected to wiring on the electro-optical panel. An electro-optical device. A method of manufacturing the electro-optical device according to claim 1,
Placing the integrated circuit element on the flexible printed circuit board so that the first terminal pad of the integrated circuit element is placed on the wiring on the flexible printed circuit board;
A step of arranging the integrated circuit element on the electro-optical panel so that the second terminal pad of the integrated circuit element is placed on the wiring on the electro-optical panel. Method. In the step of disposing the integrated circuit element on the flexible printed circuit board, an anisotropic conductive adhesive is interposed between the first terminal pad of the integrated circuit element and the wiring on the flexible printed circuit board,
In the step of disposing the integrated circuit element on the electro-optical panel, an anisotropic conductive adhesive is interposed between the second terminal pad of the integrated circuit element and the wiring on the electro-optical panel,
The first terminal pad and the wiring on the flexible printed circuit board, and the second terminal pad and the wiring on the electro-optical panel are bonded simultaneously with these anisotropic conductive adhesives. Item 3. A method for manufacturing the electro-optical device according to Item 2. An image carrier;
A charger for charging the image carrier;
2. The electro-optical device according to claim 1, wherein a latent image is formed by irradiating light emitted from the electro-optical panel onto a charged surface of the image carrier.
A developer that forms a visible image on the image carrier by attaching toner to the latent image;
An image printing apparatus comprising: a transfer unit that transfers the visible image from the image carrier to another object. The electro-optical device according to claim 1,
An image reading device comprising: a light receiving device that converts light emitted from the electro-optical panel and reflected by a reading target into an electric signal.

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