JP2009094960A - Image reader - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image reader in which an EL element is used as a light source, and which has the light source capable of efficiently emitting light. <P>SOLUTION: The light source is constituted of a plurality of EL elements including organic EL elements 20a, 20b, and irradiates an original P with the light. A light receiving element 26 receives the light reflected on the original P. Each of the organic EL elements 20a, 20b includes a light emission layer which emits the light, and a transparent substrate having the shape larger than that of the light emission layer in plane view. The organic EL element 20b is arranged so that the light emitted by the organic EL element 20a passes a non-light emitted area formed by projecting the transparent substrate from the light emitting part in such a state that the organic EL element 20b is planarly viewed. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an image reading apparatus, and more particularly to an image reading apparatus that reads an image of a document by irradiating light on the document and receiving light reflected on the document.

  In an image reading apparatus, an image of an original is read by irradiating the original with light from a light source and receiving light reflected from the original with a light receiving element. As a light source in such an image reading apparatus, a fluorescent lamp is generally used. Fluorescent lamps have the advantage that light with sufficient intensity can be obtained, but also have the disadvantage that an inverter is required. Specifically, when the inverter is mounted on the slider of the image reading apparatus together with the fluorescent lamp, the weight of the slider increases, which causes a problem that a large load is applied to the motor for driving the slider.

  Therefore, in recent years, organic electroluminescence elements (hereinafter referred to as organic EL elements) have been developed, and it has been proposed to use the organic EL elements as a light source of an image reading device (for example, see Patent Document 1). . The organic EL element has advantages such as high luminous efficiency, uniform light emission, and low heat generation.

  In an image reading apparatus in which an organic EL element is used as a light source, in order to obtain light with sufficient intensity, for example, increasing the drive current of the organic EL element or increasing the area of the organic EL element Can be mentioned. However, when the drive current of the organic EL element is increased, there is a problem that the life of the organic EL element is shortened. Moreover, in an organic EL element, since it is necessary to form uniformly the organic material used as a light emitting layer, it is difficult to enlarge the area of an organic EL element.

  Therefore, it is conceivable to arrange a plurality of organic EL elements in parallel. Thereby, the area of the light source can be increased. However, when organic EL elements are juxtaposed, there is a problem that a region that does not contribute to light emission occurs. Hereinafter, description will be given with reference to the drawings. FIG. 10A is a cross-sectional structure diagram of the organic EL element 50, and FIG. 10B is a cross-sectional structure diagram of the organic EL elements 50 arranged in parallel.

  As shown in FIG. 10A, the organic EL element 50 includes a transparent substrate 52, a transparent electrode 54, a light emitting layer 56, a back electrode 58, and a sealing member 60. The transparent substrate 52 is a transparent substrate made of glass or resin. The transparent electrode 54 is formed on the transparent substrate 52, and is a transparent electrode made of, for example, ITO (Indium Tin Oxide). The light emitting layer 56 is a plastic (or ceramic) layer formed on the transparent electrode 54 and coated or mixed with a phosphor. The back electrode 58 is formed on the light emitting layer 56 and is, for example, an electrode made of metal.

  In the organic EL element 50 configured as described above, an AC voltage is applied between the transparent electrode 54 and the back electrode 58. Thereby, the light emitting layer 56 emits light, and light is emitted from the transparent substrate 52. In addition, since the structure and light emission principle of the organic EL element 50 are known, further description is abbreviate | omitted.

  By the way, since the light emitting layer 56 is made of an organic material, it has a problem that it easily deteriorates due to moisture in the air. Therefore, as shown in FIG. 10A, in the organic EL element 50, the surfaces of the transparent electrode 54, the light emitting layer 56, and the back electrode 58 are covered with a sealing member 60 made of resin or the like. This prevents the light emitting layer 56 from coming into contact with air.

However, the organic EL element 50 provided with the sealing member 60 has a problem in that a region that does not contribute to light emission occurs when juxtaposed. More specifically, as shown in FIG. 10A, the sealing member 60 covers the side surfaces of the transparent electrode 54, the light emitting layer 56, and the back electrode 58. Therefore, the transparent substrate 52 needs to be formed larger than the transparent electrode 54, the light emitting layer 56, and the back electrode 58 in a plan view. As a result, as shown in FIG. 10A, a frame portion A that does not contribute to light emission is formed in the organic EL element 50. When the organic EL elements 50 having such a frame portion A are juxtaposed, as shown in FIG. 10B, the transparent electrodes 54, the light emitting layers 56, and the back electrodes 58 of the organic EL elements 50 that are adjacent to each other. In the middle, the frame part A is located. As a result, a region that does not contribute to light emission occurs in a light source in which a plurality of organic EL elements 50 are juxtaposed.
JP 2000-115470 A

  SUMMARY OF THE INVENTION An object of the present invention is to provide an image reading apparatus using an EL element as a light source and having a light source that can emit light more efficiently.

  The present invention comprises a plurality of EL elements including a first EL element and a second EL element, and includes a light source that irradiates light on a document, and a light receiving element that receives light reflected from the document. Each of the first EL element and the second EL element includes a light emitting portion that emits light, and a transparent substrate having a shape larger than that of the light emitting portion in a plan view. Is arranged so that the light emitted from the second EL element passes through the non-light emitting portion where the transparent substrate protrudes from the light emitting portion in a state in which the first EL element is viewed in plan view. It is characterized by that.

  According to the present invention, the first EL element emits a non-light-emitting portion in which the transparent substrate protrudes from the light-emitting portion in a state where the first EL element is viewed in plan view. It is arranged so that the transmitted light can pass. As a result, in an image reading apparatus in which a plurality of EL elements are used as light sources, light is emitted also from the non-light emitting portion of the first EL element that does not contribute to light emission. As a result, it is possible to provide an image reading apparatus in which an EL element is used as a light source and provided with a light source that can emit light more efficiently.

  In the present invention, an angle formed by the transparent substrate of the first EL element and the transparent substrate of the second EL element may be smaller than 180 degrees.

  In the present invention, the light reflected from the document may pass through the non-light emitting portion of the first EL element and the non-light emitting portion of the second EL element and enter the light receiving element.

  In the present invention, the non-light emitting portion of the first EL element may overlap the transparent substrate of the second EL element in a plan view.

  In the present invention, the light emitting portion of the first EL element has two transparent electrodes and a light emitting layer disposed between the two transparent electrodes, and the first EL element includes: The second EL element may be placed on top of the second EL element.

  In the present invention, the EL element may further include a sealing portion that covers the light emitting portion.

(First embodiment)
The image reading apparatus 10a according to the first embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional structure diagram of an image reading apparatus 10a according to the first embodiment.

  The image reading device 10a is a device that reads an image of the document P by irradiating the document P with light and receiving light reflected from the document P. The image reading device body 12, the platen glass 14, and the slider 16. The image reading device 10a is a device that adopts a so-called contact image sensor method.

  The image reading device main body 12 is a housing of the image reading device 10a, and stores a slider 16 therein. Furthermore, the upper surface of the image reading apparatus main body 12 is opened, and a platen glass 14 is fitted in the opening. The platen glass 14 is made of transparent glass or resin, and the document P is placed on the upper surface thereof.

  The slider 16 moves in the direction of the arrow in FIG. 1, reads an image of the original P, and includes a slider body 18, organic EL elements 20 and 22, an equal magnification lens 24, and a light receiving element 26. The slider body 18 is a housing of the slider 16 and stores the organic EL elements 20 and 22, the equal magnification lens 24 and the light receiving element 26 therein. Furthermore, the upper surface of the slider body 18 is open.

  The organic EL elements 20 and 22 are elements that emit light when a voltage is applied, and function as a light source L that irradiates the original P with light. The organic EL element 22 is disposed on the organic EL element 20 so as to overlap. The configuration of the organic EL elements 20 and 22 will be described later.

  Light emitted from the organic EL elements 20 and 22 passes through the platen glass 14 and irradiates the original P. Further, the light emitted from the organic EL elements 20 and 22 is reflected by the original P and enters the equal magnification lens 24. The equal magnification lens 24 images the light reflected from the original P on the light receiving surface of the light receiving element 26 at equal magnification. The light receiving element 26 is configured by, for example, a CCD (Charge Coupled Devices) element, and is an element that generates an electrical signal corresponding to the intensity of incident light. In the present embodiment, the light receiving element 26 receives the light reflected by the document P and generates an electrical signal corresponding to the intensity of the light. With the configuration described above, the image reading device 10a reads an image of the document P.

  Next, the organic EL elements 20 and 22 will be described with reference to FIG. 2A is a cross-sectional structure diagram of the organic EL elements 20 and 22, and FIG. 2B is a view of the organic EL elements 20 and 22 viewed from the normal direction of these main surfaces (hereinafter, a plan view). FIG. 2C is a graph showing the intensity of light emitted from the organic EL elements 20 and 22. In FIG. 2C, the vertical axis indicates the light intensity, and the horizontal axis indicates the positions of the organic EL elements 20 and 22. Hereinafter, in FIG. 2A, the upward direction in the normal direction with respect to the main surfaces of the organic EL elements 20 and 22 is simply defined as the upward direction, and the downward direction in the normal direction with respect to the main surfaces of the organic EL elements 20 and 22 is defined as It is simply defined as downward.

  First, the organic EL element 20 will be described. The organic EL element 20 includes a transparent substrate 32, a transparent electrode 34, a light emitting layer 36, a back electrode 38 and a sealing member 39. The transparent substrate 32 is a transparent substrate made of glass or resin. The transparent electrode 34 is formed on the transparent substrate 32 and is a transparent electrode made of, for example, ITO (Indium Tin Oxide). The light emitting layer 36 is a plastic (or ceramic) layer formed on the transparent electrode 34 and coated or mixed with a phosphor. The back electrode 38 is formed on the light emitting layer 36 and is, for example, an electrode made of a metal that reflects light. As described above, the light emitting layer 36 is sandwiched between the transparent electrode 34 and the back electrode 38. The transparent electrode 34, the light emitting layer 36, and the back electrode 38 constitute the light emitting part B.

  Furthermore, in order to prevent the light emitting layer 36 from being deteriorated by moisture in the air, a sealing member 39 made of resin covers the transparent electrode 34, the light emitting layer 36 and the back electrode 38. This prevents the light emitting layer 36 from coming into contact with air.

  Here, since the transparent electrode 34, the light emitting layer 36, and the back electrode 38 are covered with the sealing member 39, as shown in FIG. It is formed larger than (the transparent electrode 34, the light emitting layer 36, and the back electrode 38). Thereby, the frame part C which protrudes from the light emission part B is formed. The frame portion C is a non-light emitting portion that does not contribute to the light emission of the organic EL element 20.

Next, the organic EL element 22 will be described. The organic EL element 22 includes a transparent substrate 42, a transparent electrode 44, a light emitting layer 46, a back electrode 48, and a sealing member 49. The transparent substrate 42 is a transparent substrate made of glass or resin. The transparent electrode 44 is formed on the transparent substrate 42 and is a transparent electrode made of, for example, ITO (Indium Tin Oxide). The light emitting layer 46 is a plastic (or ceramic) layer formed on the transparent electrode 44 and coated or mixed with phosphors. The back electrode 48 is formed on the light emitting layer 46 and is a transparent electrode made of, for example, IZO (In ₂ O ₃ —ZnO). As described above, the light emitting layer 46 is sandwiched between the transparent electrode 44 and the back electrode 48. The transparent electrode 44, the light emitting layer 46, and the back electrode 48 constitute a light emitting part B ′.

  Further, a sealing member 49 made of resin covers the transparent electrode 44, the light emitting layer 46, and the back electrode 48 in order to prevent the light emitting layer 46 from being deteriorated by moisture in the air. This prevents the light emitting layer 46 from coming into contact with air.

  Here, since the transparent electrode 44, the light emitting layer 46, and the back electrode 48 are covered with the sealing member 49, as shown in FIG. It is formed larger than '(the transparent electrode 44, the light emitting layer 46, and the back electrode 48). As a result, a frame portion C ′ protruding from the light emitting portion B ′ is formed. The frame portion C ′ does not contribute to the light emission of the organic EL element 22.

  The organic EL element 22 configured as described above is disposed so as to overlap the organic EL element 20. An alternating voltage is applied between the transparent electrode 34 and the back electrode 38, and an alternating voltage is applied between the transparent electrode 44 and the back electrode 48. Thereby, the light emitting layers 36 and 46 emit light, and light is emitted from the light emitting layers 36 and 46 in the vertical direction. Below, the path | route of the light radiate | emitted from the light emitting layers 36 and 46 is demonstrated.

  As shown in FIG. 2A, the light 11 emitted upward from the light emitting layer 36 passes through the organic EL element 22 and is emitted upward because the back electrode 48 is a transparent electrode. The light 12 emitted downward from the light emitting layer 36 is reflected by the back electrode 38 which is a metal electrode, passes through the organic EL elements 20 and 22, and is emitted upward.

  The light l3 emitted upward from the light emitting layer 46 is emitted upward from the organic EL element 22. Since the back electrode 48 is a transparent electrode, the light 14 emitted downward from the light emitting layer 46 is incident on the organic EL element 20 and reflected by the back electrode 38 that is a metal electrode. Passes and exits upward.

  As described above, among the light emitted from the light emitting layers 36 and 46, the light l1 and l3 emitted upward are emitted upward as they are, and the lights l2 and l4 emitted downward are metal electrodes. The light is reflected upward at the back electrode 38 and emitted upward. As a result, all the light emitted from the organic EL elements 20 and 22 is emitted upward. As a result, it is possible to irradiate the original P with more intense light in the image reading apparatus 10a. In the present embodiment, as shown in FIG. 2C, the light intensity of the organic EL elements 20 and 22 indicated by the dotted lines is overlapped, so that the light having the intensity indicated by the solid lines is emitted. , 22 from the light source L.

  Furthermore, in the image reading apparatus 10a, the organic EL element 20 and the organic EL element 22 are disposed so as to overlap each other. Therefore, the light emitted from the organic EL element 20 disposed on the lower side passes through the frame portion C ′ of the organic EL element 22 as shown in FIG. As a result, in the image reading apparatus 10a in which the plurality of organic EL elements 20 and 22 are used as the light source L, light is emitted from the frame portion C ′ that does not contribute to light emission. Thereby, in the image reading apparatus 10a, it can suppress that the useless area | region which does not contribute to light emission generate | occur | produces. The phrase “light passes through the frame portion C ′” means that light having a luminance of 80% or more of the front luminance of the organic EL element 20 is emitted from the frame portion C ′.

(Second Embodiment)
The image reading apparatus 10b according to the second embodiment of the present invention will be described below with reference to the drawings. FIG. 3 is a cross-sectional structure diagram of an image reading apparatus 10b according to the second embodiment. In the components of the image reading device 10b according to the present embodiment, the same reference numerals are assigned to the same components as those of the image reading device 10a according to the first embodiment.

  As shown in FIG. 3, the image reading apparatus 10 b is different from the image reading apparatus 10 a in that the organic EL elements 20 a and 20 b are arranged so as to be shifted. This difference will be described below with reference to FIG. 4A is a cross-sectional structure diagram of the organic EL elements 20a and 20b, and FIG. 4B is a diagram of the organic EL elements 20a and 20b viewed from the normal direction of these main surfaces. 4 (c) is a graph showing the intensity of light emitted from the organic EL elements 20a and 20b. In FIG.4 (c), a vertical axis | shaft has shown the intensity | strength of light and the horizontal axis has shown the position of organic EL element 20a, 20b.

  The organic EL elements 20a and 20b used in the image reading apparatus 10b are the same as the organic EL elements 20 used in the image reading apparatus 10a. Therefore, the description of the configuration of the organic EL elements 20a and 20b is omitted. In the present embodiment, a or b is added after the reference symbol in order to distinguish each organic EL element.

  The frame portion Cb overlaps the transparent substrate 32a of the organic EL element 20a in a plan view. Thereby, the light emitted from the organic EL element 20a passes through the frame portion Cb. As a result, in the image reading apparatus 10b in which the plurality of organic EL elements 20a and 20b are used as the light source L, light is emitted from the frame portion Cb that does not contribute to light emission. Thereby, in the image reading apparatus 10b, it can suppress that the useless area | region which does not contribute to light emission generate | occur | produces. Note that light passing through the frame portion Cb means that light having a luminance of 80% or more of the front luminance of the organic EL element 20a is emitted from the frame portion Cb.

  Further, in the image reading apparatus 10b, as shown in FIGS. 4A and 4B, the light emitting portions Ba and Bb are close to each other. Therefore, as shown in FIG. 4C, the intensity of light emitted from the vicinity of the region where the organic EL element 20a and the organic EL element 20b overlap (near the central portion of the light source L) is the intensity of light emitted from other regions. It becomes stronger than strength. As a result, in the image reading apparatus 10b, it is possible to irradiate the original P with concentrated light.

(First modification)
Hereinafter, an image reading apparatus 10c according to a first modification of the image reading apparatus 10b will be described with reference to FIGS. FIG. 5 is a cross-sectional structure diagram of an image reading apparatus 10c according to the first modification. In the components of the image reading device 10c, the same components as those of the image reading device 10b are denoted by the same reference numerals.

  The image reading device 10c is different from the image reading device 10b in the arrangement method of the organic EL elements 20a and 20b. Specifically, in the image reading apparatus 10c, as shown in FIG. 5, the organic EL elements 20a and 20b are formed by an angle formed between the organic EL element 20a and the organic EL element 20b (the transparent substrate 32a and the transparent substrate 32b are formed). (The angle) is smaller than 180 degrees. This difference will be described below with reference to FIG.

  6A is a cross-sectional structure diagram of the organic EL elements 20a and 20b, and FIG. 6B is a diagram of the organic EL elements 20a and 20b viewed from the normal direction of these main surfaces. 6 (c) is a graph showing the intensity of light emitted from the organic EL elements 20a and 20b. In FIG. 6C, the vertical axis indicates the light intensity, and the horizontal axis indicates the positions of the organic EL elements 20a and 20b.

  The organic EL elements 20a and 20b used in the image reading device 10c are the same as the organic EL elements 20a and 20b used in the image reading device 10b.

  The frame portion Cb overlaps the transparent substrate 32a of the organic EL element 20a in a plan view. Thereby, the light emitted from the organic EL element 20a passes through the frame portion Cb. As a result, in the image reading apparatus 10c in which the plurality of organic EL elements 20a and 20b are used as the light source L, light is emitted from the frame portion Cb that does not contribute to light emission. Thereby, in the image reading apparatus 10c, it can suppress that the useless area | region which does not contribute to light emission generate | occur | produces. Note that light passing through the frame portion Cb means that light having a luminance of 80% or more of the front luminance of the organic EL element 20a is emitted from the frame portion Cb.

  Further, the light emitted from the organic EL element 20a and the organic EL element 20b in the image reading apparatus 10c is more concentrated than the light emitted from the organic EL element 20a and the organic EL element 20b in the image reading apparatus 10b. Will come to irradiate. As a result, in the image reading apparatus 10c, it is possible to irradiate the original P with concentrated light. This will be described below.

  Light emitted from the organic EL elements 20a and 20b is emitted so as to spread upward. Therefore, when light is irradiated onto the original P by the light source L composed of the organic EL elements 20a and 20b, light that does not contribute to reading the image of the original P is generated. Therefore, in the image reading apparatus 10c, the organic EL elements 20a and 20b are arranged so that the angle formed by the transparent substrate 32a and the transparent substrate 32b is smaller than 180 degrees. Thereby, as shown in FIG.6 (c), the spreading | diffusion of the light radiate | emitted from the light source L which consists of organic EL element 20a, 20b is suppressed. As a result, according to the image reading device 10c, it is possible to suppress the generation of light that does not contribute to reading the image of the original P.

  Furthermore, since the organic EL elements 20a and 20b are disposed at an inclination, the light is concentrated at the center of the light source L composed of the organic EL elements 20a and 20b. As a result, as shown in FIGS. 4C and 6C, the intensity of the light emitted from the central portion of the light source L in the image reading device 10c is changed from the central portion of the light source L in the image reading device 10b. It becomes stronger than the intensity of the emitted light. As a result, the image reading apparatus 10c can concentrate on the original P and irradiate light with higher intensity.

(Second modification)
Hereinafter, an image reading device 10d according to a second modification of the image reading device 10b will be described with reference to FIG. FIG. 7 is a cross-sectional structure diagram of an image reading apparatus 10d according to a second modification. In the components of the image reading device 10d, the same components as those of the image reading device 10c are denoted by the same reference numerals.

  The image reading device 10d is different from the image reading device 10c in the position where the organic EL elements 20a and 20b are arranged. Specifically, in the image reading apparatus 10d, organic EL elements 20a and 20b are disposed between the platen glass 14 and the equal magnification lens 24. This difference will be described below with reference to FIG.

  As shown in FIG. 7, the platen glass 14, the organic EL elements 20a and 20b, and the equal-magnification lens 24 are arranged in a straight line in this order. Further, similarly to the organic EL elements 20a and 20b of the image reading device 10c, the organic EL elements 20a and 20b of the image reading device 10d are configured so that the angle formed by the transparent substrate 32a and the transparent substrate 32b is smaller than 180 degrees. Has been placed.

  By arranging the organic EL elements 20a and 20b as described above, the light emitted from the organic EL elements 20a and 20b is reflected on the original P, and the frame portions Ca and Cb of the organic EL elements 20a and 20b (FIG. 7). Will pass through (not shown). Further, the light that has passed through the frame portions Ca and Cb passes through the equal magnification lens 24 and enters the light receiving element 26.

  According to the image reading device 10d, the slider 16 can be made compact by arranging the platen glass 14, the organic EL elements 20a and 20b, and the equal magnification lens 24 so as to be arranged in a straight line. As a result, the image reading device 10d can be made compact.

(Other embodiments)
The image reading devices 10a to 10d according to the present invention are not limited to the above-described embodiment, and can be variously modified within the scope of the gist.

  In the image reading devices 10a to 10d, only two organic EL elements are used, but the number of organic EL elements is not limited to two as long as it is plural. FIG. 8A is a top view of the light source L composed of a plurality of organic EL elements 20, and FIG. 8B is a side view of the light source L. In FIG. 8B, each organic EL element 20 is shown by a straight line for the sake of simplicity.

  As shown in FIG. 8, each organic EL element 20 is arranged so as to be partially overlapped with the adjacent organic EL element 20. Further, as shown in FIG. 8B, the organic EL elements 20 located at both ends are arranged in a state where they are raised with respect to the other organic EL elements 20. By adjusting the rising angle of the organic EL elements 20 located at both ends, the intensity of the light condensed on the central portion of the light source L can be adjusted. By this adjustment, the illuminance distribution on the light receiving surface of the light receiving element can be made uniform, and the accuracy of the electrical signal output from the light receiving element can be improved. As a result, it is possible to suppress the occurrence of quantization error that occurs when the electrical signal is converted into a digital signal and corrected.

  Although the image reading devices 10a to 10d are contact image sensor type image reading devices, the image reading method is not limited to this. Examples of the image reading method include a mirror scan method and a unit scan method. Since the mirror scanning type image reading apparatus is generally well known, description thereof is omitted. A unit scan type image reading apparatus will be described below with reference to FIG. FIG. 9 is a cross-sectional structure diagram of a unit scan type image reading apparatus 10e.

  In the contact image sensor type image reading devices 10a to 10d, the light emitted from the light source L is incident on the light receiving element 26 without being reflected by the mirror. On the other hand, in the unit scan type image reading apparatus 10e, the light emitted from the light source L composed of the organic EL elements 20 and 22 is reflected by the mirrors 21a to 21e and enters the reduction lens 23. The reduction lens 23 condenses the incident light and forms an image on the light receiving surface of the light receiving element 26. The reason why the mirrors 21a to 21e are provided in the image reading device 10e will be described below.

  In the unit scan type image reading apparatus 10 e, the reduction lens 23 reduces the image of the original P and forms an image on the light receiving element 26. As described above, in order to reduce the image of the original P, the distance between the organic EL elements 20 and 22 and the reduction lens 23 shown in FIG. 9 is set so that the organic EL elements 20 and 22 shown in FIG. It needs to be longer than the distance. Therefore, in the image reading apparatus 10e, the distance between the organic EL elements 20 and 22 and the reduction lens 23 is ensured by bending the light path with the mirrors 21a to 21e.

  In the image reading apparatuses 10a to 10e, an organic EL element is used as the light source L. However, for example, an inorganic EL element may be used as the light source L.

  In the image reading apparatuses 10a to 10e, the organic EL elements having the same size are used, but organic EL elements having different sizes may be used.

1 is a cross-sectional structure diagram of an image reading apparatus according to a first embodiment. 2A is a cross-sectional structural view of the organic EL element, and FIG. 2B is a view of the organic EL element as viewed from the normal direction of these main surfaces (hereinafter referred to as a plan view). FIG. 2C is a graph showing the intensity of light emitted from the organic EL element. FIG. 3 is a cross-sectional structure diagram of an image reading apparatus according to the second embodiment. 4A is a cross-sectional structure diagram of the organic EL element, FIG. 4B is a diagram of the organic EL element viewed from the normal direction of these main surfaces, and FIG. It is the graph which showed the intensity | strength of the light which an organic EL element radiate | emits. FIG. 6 is a cross-sectional structure diagram of an image reading apparatus according to a first modification. 6A is a cross-sectional structure diagram of the organic EL element, FIG. 6B is a diagram of the organic EL element viewed from the normal direction of these main surfaces, and FIG. It is the graph which showed the intensity | strength of the light which an organic EL element radiate | emits. It is a cross-section figure of the image reading device which concerns on a 2nd modification. FIG. 8A is a top view of a light source composed of a plurality of organic EL elements, and FIG. 8B is a side view of the light source. 1 is a cross-sectional view of a unit scan type image reading apparatus. FIG. 10A is a cross-sectional structure diagram of an organic EL element, and FIG. 10B is a cross-sectional structure diagram of a plurality of juxtaposed organic EL elements.

Explanation of symbols

B, B ', Ba, Bb Light emitting part C, C', Ca, Cb Frame part P Original 10a, 10b, 10c, 10d, 10e Image reading device 20, 20a, 20b, 22 Organic EL element 26 Light receiving element 32, 32a , 32b, 42 Transparent substrate 34, 44 Transparent electrode 36, 46 Light emitting layer 38, 48 Rear electrode 39, 39a, 39b, 49 Sealing member

Claims (6)

A light source that includes a plurality of EL elements including a first EL element and a second EL element, and irradiates light on the document;
A light receiving element for receiving light reflected from the original;
With
The first EL element and the second EL element are respectively
A light emitting unit for emitting light;
In a state in plan view, a transparent substrate having a shape larger than the light emitting part,
Including
In the first EL element, the light emitted from the second EL element passes through a non-light-emitting portion formed by protruding the transparent substrate from the light-emitting portion in a state where the first EL element is viewed in plan view. To be arranged,
An image reading apparatus characterized by the above. An angle formed by the transparent substrate of the first EL element and the transparent substrate of the second EL element is smaller than 180 degrees;
The image reading apparatus according to claim 1. The light reflected from the original passes through the non-light emitting portion of the first EL element and the non-light emitting portion of the second EL element and enters the light receiving element;
The image reading apparatus according to claim 2. The non-light emitting portion of the first EL element overlaps the transparent substrate of the second EL element in a plan view;
The image reading apparatus according to claim 1, wherein: The light emitting portion of the first EL element is:
Two transparent electrodes,
A light emitting layer disposed between the two transparent electrodes;
Have
The first EL element is disposed over the second EL element;
The image reading apparatus according to claim 1. The EL element is
A sealing portion covering the light emitting portion,
Including further,
The image reading apparatus according to claim 1, wherein the image reading apparatus is an image reading apparatus.

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