JP2009135653A - Light source device and image reader with the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light source device provided with a planar light source such as an EL element, and in which use efficiency of light is high, and an image reader provided with the same. <P>SOLUTION: The light source device 26 is used for the image reader and irradiates an original with light. A transparent substrate 102 is composed of a first main surface 104, a second main surface 106, and side faces 108, 110, 112, 114. An emission part 100 is provided on the first main surface 104. A reflection member 116 is provided so that its reflection surface faces the emission part 100 on the second main surface 106. The light emitted from the emission part 100 to the inside of the transparent substrate 102 is emitted from the side face 110 where the reflection member 116 and the emission part 110 are not provided to the outside of the transparent substrate 102. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a light source device and an image reading device including the same, and more particularly to a light source device including a planar light source and an image reading device including the same.

  In an image reading apparatus, a fluorescent lamp is generally used as a light source for irradiating a document. Since such a fluorescent lamp is generally widely used, it has an advantage that it can be obtained at a low cost.

  However, since the fluorescent lamp has a circular cross-sectional area, there is a problem that the thickness thereof is increased. Furthermore, an inverter is required to turn on the fluorescent lamp. When these fluorescent lamps and inverters are built in the slider, the weight of the slider increases, and a large load is applied to the motor that drives the slider. As a result, there is a problem that the power consumption of the image reading apparatus increases.

  As a light source for solving such a problem, for example, a document reading device described in Patent Document 1 has been proposed. The document reading apparatus includes a light source including an organic EL (electroluminescence) element and an inorganic EL element. Since the organic EL element and the inorganic EL element are configured by forming a light emitting layer on a glass substrate, the thickness thereof is thinner than that of a fluorescent lamp. Further, since an inverter is unnecessary, there is no problem of an increase in the weight of the slider. That is, the problem of an increase in power consumption of the image reading apparatus does not occur.

  However, the document reading apparatus described in Patent Document 1 has a problem that the utilization efficiency of light emitted from the light source is poor. Hereinafter, it will be described in detail with reference to the drawings. FIG. 8 is a configuration diagram of the light source device of the document reading device described in Patent Document 1, and a graph showing the light intensity distribution in the light source device. In the graph of FIG. 8, the vertical axis indicates the light intensity, and the horizontal axis indicates the position in the sub-scanning direction. The position in the configuration diagram corresponds to the position in the graph.

  FIG. 8 shows light sources 500a and 500b, a platen glass 506, a mirror 508, and a document P. The light sources 500a and 500b include light emitting portions 502a and 502b and transparent substrates 504a and 504b, respectively.

  The light sources 500a and 500b are planar light sources made of an organic EL element or an inorganic EL element, and emit surface light. More specifically, the light emitting portions 502a and 502b provided on the lower surfaces of the transparent substrates 504a and 504b emit light, and light is emitted from the upper surfaces of the transparent substrates 504a and 504b. Light from the light sources 500 a and 500 b passes through the platen glass 506 and irradiates the original P. The light irradiated on the document P is reflected at the reading position A of the document P, travels downward in FIG. 8, and is reflected toward the CCD (not shown) by the mirror 508 and a mirror (not shown). The CCD reads this light and takes an image of the original P. The above operation is performed while the light sources 500a and 500b and the mirror 508 are translated in the sub-scanning direction. As a result, the reading position A scans the entire surface of the document P, and an image of the entire surface of the document P is acquired by the CCD.

  Here, the light sources 500a and 500b are planar light sources and emit surface light. Therefore, the light emitted from the light sources 500a and 500b has an intensity distribution that spreads in the sub-scanning direction centering on the light sources 500a and 500b, as indicated by the dotted lines in FIG. As a result, the intensity distribution of the combined light of the light irradiated by the light sources 500a and 500b has an intensity distribution that spreads in the sub-scanning direction with the reading position A as the center, as shown by the solid line in FIG.

However, the light used for reading the image of the original P is only the light that irradiates the reading position A of the original P. Specifically, the light incident on the CCD is light reflected at the reading position A of the original P among the light reflected on the original P. The width of the reading position A of the document P is about 10 pixels in the color image reading apparatus. Thus, since the reading position A of the document P has a very narrow width, most of the light emitted from the light sources 500a and 500b irradiates other than the reading position A of the document P. As a result, most of the light emitted from the light sources 500a and 500b is not used for reading the image of the document P, and the light use efficiency is lowered.
JP 2000-115470 A

  SUMMARY OF THE INVENTION An object of the present invention is to provide a light source device that includes a planar light source such as an EL element and has high light utilization efficiency, and an image reading device including the light source device.

  According to a first aspect of the present invention, there is provided a light source device that is used in an image reading apparatus and that irradiates light on a document, and is provided on a transparent substrate having a first main surface, a second main surface, and side surfaces, And a first reflecting member provided on the second main surface so that a reflecting surface faces the planar light source, from the planar light source into the transparent substrate. The emitted light is emitted outside the transparent substrate from a portion where the first reflection member and the planar light source are not provided.

  According to the first invention, since the first reflecting member is provided on the second main surface, the light to be emitted from the second main surface is provided with the first reflecting member and the planar light source. The light is emitted from the non-exposed portion to the outside of the transparent substrate. Therefore, the light emitted from the planar light source is concentrated from a portion where the first reflecting member and the planar light source are not provided and is emitted to the outside of the transparent substrate. That is, according to the first invention, the light intensity distribution can be concentrated by limiting the light emission surface. As a result, according to the first aspect of the invention, the light can be concentrated at the reading position of the document of the image reading apparatus, and the light use efficiency can be improved.

  In the first invention, the first reflecting member may cover the entire surface of the second main surface.

  In the first invention, at least a part of the side surface of the transparent substrate may further include a second reflecting member provided so that the reflecting surface faces the transparent substrate.

  In the first invention, the image reading apparatus includes a transparent plate for placing a document, and the transparent substrate is disposed substantially parallel to the transparent plate, and the first of the side surfaces is the first plate. The side surface on which the reflecting member 2 is not provided may be inclined with respect to the second main surface so as to face the transparent plate.

  1st invention WHEREIN: The side surface in which the said 2nd reflection member is not provided among the said side surfaces is inclined with respect to the said 2nd main surface so that it may face the said transparent plate, And a third reflecting member facing the vertical surface, and the light emitted from the vertical surface to the outside of the transparent substrate is the third reflecting member. The reflective member may be reflected toward the transparent plate.

  In the first invention, the distance between the first main surface and the second main surface may increase as the distance from the side surface on which the second reflecting member is not provided is increased.

  In the first invention, the transparent substrate has a rectangular shape when viewed in plan, and the side surface of the transparent substrate includes a first side surface and a second side surface extending in a longitudinal direction, The first reflecting member may be provided on the second main surface with a gap from the first side surface and the second side surface.

  In the first invention, the image reading device includes a transparent plate for placing a document, and the transparent substrate is disposed so as to be inclined with respect to the transparent plate, and the second main surface. And a fourth reflecting member that faces the transparent substrate, and the light that is emitted from the gap between the first reflecting member and the second side surface to the outside of the transparent substrate is transmitted to the transparent substrate by the fourth reflecting member. You may reflect to the board side.

  In the first invention, the width of the gap between the first side surface and the first reflecting member may be smaller than the width of the gap between the second side surface and the first reflecting member.

  The present invention can be applied not only to a light source device but also to an image reading device including the light source device. According to a second aspect of the present invention, in the image reading device, the light source device is provided.

  In the second invention, the light source device may move in parallel to the document.

  In the second aspect of the invention, the light source device may further include a conveying unit that conveys the document.

(First embodiment)
Embodiments of a light source device and an image reading apparatus including the light source device according to the first embodiment of the present invention will be described below with reference to the accompanying drawings.

(Overall configuration of image reading device)
FIG. 1 is a configuration diagram of a copying machine 1 including an image reading device 3 according to the first embodiment. The copying machine 1 includes a document conveying device 2 as a document conveying unit that conveys a document P so as to pass a reading position A, an image reading device 3 including a reading unit that optically reads an image of the document P, and And an image forming apparatus 4 that prints an image of the original P on a paper S. Then, the image reading device 3 is a platen set method for reading an image of the document P placed on the platen glass 46 and a sheet-through method for reading an image of the document P conveyed on the platen glass 44 by the document conveying device 2. Two types of image reading methods can be executed.

  Hereinafter, for simplification of description, “the conveyance direction of the document P on the platen glass 44” is referred to as “sub-scanning direction”, and “upstream side of the document P in the sub-scanning direction” is simply referred to as “upstream side”. The “downstream side of the document P in the sub-scanning direction” is simply referred to as “downstream side”. Further, a direction perpendicular to the paper surface of FIG. 1 is defined as a “main scanning direction”.

  First, the configuration of the document conveying device 2 will be described. The document feeder 2 includes a paper feed tray 6, a pickup roller 8, a separating roller 10, a paper feed roller 12, a registration roller pair 14, a pre-reading roller pair 16, a post-reading roller pair 18, a paper discharge roller pair 20, and a paper discharge tray. 22.

  A plurality of documents P are placed on the sheet feed tray 6. The pickup roller 8 picks up a part of a plurality of documents P. The separating roller 10 and the sheet feeding roller 12 separate and convey one by one when a plurality of documents P are picked up by the pickup roller 8. The registration roller pair 14 corrects the skew of the original P that has been conveyed one by one and conveys it to the pre-reading roller pair 16. The pre-reading roller pair 16 conveys the document P onto the platen glass 44. After reading, the roller pair 18 conveys the original P that has passed over the platen glass 44 to the paper discharge roller pair 20. The paper discharge roller pair 20 discharges the original P conveyed from the roller pair 18 after reading onto the paper discharge tray 22.

  Next, the configuration of the image reading device 3 will be described. The image reading device 3 is a device that irradiates the original P with light and reads the light reflected by the original P to obtain an image of the original P, and includes a first slider 26, a second slider 28, and an imaging lens 30. CCD 32 and platen glasses 44 and 46 are provided. The first slider 26 functions as a light source device that irradiates the document P with light, and includes light source units 36 a and 36 b and a first mirror 38. Therefore, hereinafter, the first slider 26 is referred to as a light source device 26. The second slider 28 includes a second mirror 40 and a third mirror 42.

  The platen glass 44 is a transparent plate through which the document P passes. A reading position A exists on the platen glass 44. When the image of the document P is read by the sheet-through method, the image of the document P is read when the document P passes through the reading position A.

  The platen glass 46 is a transparent plate on which the document P is placed. When the image of the document P is read by the platen setting method, the document P is placed on the platen glass 46 and the light source device 26 is scanned in the sub-scanning direction, so that the reading position A is on the document P. Are scanned, and the image of the original P is read.

  The light source parts 36a and 36b, the first mirror 38, the second mirror 40, the third mirror 42, the imaging lens 30 and the CCD 32 serve as reading means for optically reading the image of the document P. Specifically, the light source units 36 a and 36 b irradiate the original P with light. Details of the light source unit 36 will be described later. The first mirror 38, the second mirror 40, and the third mirror 42 serve to guide the light reflected from the document P to the imaging lens 30. Specifically, the first mirror 38 reflects the light reflected by the document P in the left direction in FIG. The second mirror 40 reflects the light reflected by the first mirror 38 downward in FIG. The third mirror 42 reflects the light reflected by the second mirror 40 in the right direction in FIG.

  The imaging lens 30 plays a role of imaging the light reflected by the first mirror 38, the second mirror 40 and the third mirror 42 onto the CCD 32. The CCD 32 has a light receiving area for three lines composed of R, G, and B (R: red, G: green, B: blue) extending in the main scanning direction, and reads the light reflected by the document P to read in the main scanning direction. 3 lines of R, G, and B extending in the direction can be taken.

  Here, when the image of the document P is read by the sheet-through method, the light source device 26 and the second slider 28 are positioned below the platen glass 44 and do not move as shown in FIG. On the other hand, when reading the image of the document P by the platen setting method, the light source device 26 and the second slider 28 move in parallel in the sub-scanning direction under the platen glass 46. The moving speed of the light source device 26 is twice the moving speed of the second slider 28. Thereby, even if the light source device 26 and the second slider 28 move, the optical distance from the document P to the CCD 32 is prevented from changing.

  Next, the configuration of the image forming apparatus 4 will be described. The image forming apparatus 4 is an electrophotographic color printer and is configured to synthesize images of four colors (C: cyan, M: magenta, Y: yellow, K: black) in a so-called tandem system. is there. The image forming apparatus 4 has a function of forming an image of the original P read by the image reading apparatus 3 on the paper S, and includes a printing unit 52, a paper feeding unit 54, a control unit 56, a fixing device 58, and a paper discharge tray 60. Prepare.

  The control unit 56 is constituted by a CPU, for example, and controls the operation of the entire copying machine 1. For example, the control unit 56 converts R, G, B image data generated by the CCD 32 of the image reading device 3 into Y, M, C, K image data.

  The paper supply unit 54 serves to supply the paper S one by one, and includes a paper tray 64 and a paper supply roller 66. The paper tray 64 is loaded with a plurality of sheets S in a state before printing. The paper feed roller 66 takes out the paper S placed on the paper tray 64 one by one.

  The printing unit 52 serves as an image printing unit that prints an image on the paper S supplied from the paper feeding unit 54, and includes an image forming station 68 (68Y, 68M, 68C, 68K) and a primary transfer roller 70 ( 70Y, 70M, 70C, 70K), transfer belt 72, drive roller 74, driven roller 76, secondary transfer roller 78, cleaning blade 80, and exposure device 82. The image forming station 68 (68Y, 68M, 68C, 68K) includes a photosensitive drum 84 (84Y, 84M, 84C, 84K), a charger 86 (86Y, 86M, 86C, 86K), and a developing device 88 (88Y, 88K). 88M, 88C, 88K) and cleaner 90 (90Y, 90M, 90C, 90K). Hereinafter, when referring to the individual image forming station 68, the primary transfer roller 70, the photosensitive drum 84, the charger 86, the developing device 88, and the cleaner 90, Y, M, C, and K are appended to the reference numerals. When the image forming station 68, the primary transfer roller 70, the photosensitive drum 84, the charger 86, the developing device 88, and the cleaner 90 are collectively referred to, Y, M, C, and K are denoted after the reference numerals. Indicate without attaching.

  The charger 86 charges the peripheral surface of the photosensitive drum 84. The exposure device 82 irradiates the photosensitive drum 84 with a beam based on the Y, M, C, and K image data converted by the control unit 56. Thereby, an electrostatic latent image is formed on the peripheral surface of the photosensitive drum 84. The developing roller of the developing device 88 forms a toner image on the peripheral surface of the photosensitive drum 84 by supplying toner to the photosensitive drum 84 on which the electrostatic latent image is formed.

  The primary transfer roller 70 transfers the toner image formed on the photosensitive drum 84 to a transfer belt 72 that is stretched between a driving roller 74 and a driven roller 76. The transfer belt 72 serves as an image carrier that carries the toner image transferred by the primary transfer roller 70.

  The drive roller 74 serves to drive the transfer belt 72 in the direction of the arrow in FIG. 1 by being rotated by a motor (not shown). The secondary transfer roller 78 serves as a transfer member that sandwiches the paper S together with the transfer belt 72 and the drive roller 74 in order to transfer the toner image onto the paper S. The toner image is conveyed to a nip portion N constituted by the drive roller 74 and the secondary transfer roller 78 by driving the transfer belt 72. A bias voltage is applied to the secondary transfer roller 78, and a toner image composed of toner particles having a negative charge is attracted to the secondary transfer roller 78 side by the bias voltage and fed. The image is transferred to the sheet S conveyed from the section 54. The cleaning blade 80 collects the toner remaining on the transfer belt 72 after the transfer of the toner image is completed. The cleaner 90 collects the toner remaining on the photosensitive drum 84.

  The fixing device 58 serves as a fixing unit that fixes the toner image on the paper S by performing heat treatment and pressure treatment on the paper S. A printed paper S is placed on the paper discharge tray 60.

(Configuration of light source device)
The configuration of the light source device 26 will be described below with reference to the drawings. FIG. 2 is a configuration diagram of the light source device 26 according to the first embodiment, and a graph showing the intensity distribution of the light that irradiates the document P. In the configuration diagram, a cross-sectional structure diagram in a plane perpendicular to the main scanning direction and a top view of the light source unit 36a are shown.

  As shown in FIG. 2, the light source device 26 includes light source units 36 a and 36 b and a first mirror 38. The light source unit 36a emits light toward the reading position A of the document P, and includes a light emitting unit 100a, a transparent substrate 102a, and reflecting members 116a, 118a, 120a, and 122a. The light source unit 36b emits light toward the reading position A of the document P, and the light emitting unit 100b, the transparent substrate 102b, and the reflecting members 116b, 118b, 120b, and 122b (the reflecting members 120b and 122b are not shown). Including. The light source unit 36a and the light source unit 36b are arranged to face each other with the reading position A interposed therebetween. Here, since the light source unit 36a and the light source unit 36b have the same configuration, the configuration of the light source unit 36 will be described by omitting a and b after the reference numerals. Further, although the light source device 26 can be located under either of the platen glasses 44 and 46, the following description will be made assuming that the light source device 26 is located under the platen glass 46.

  The light emitting unit 100 and the transparent substrate 102 are composed of organic EL elements. More specifically, the transparent substrate 102 is a glass substrate including a first main surface 104, a second main surface 106, and side surfaces 108, 110, 112, and 114, and extends in the main scanning direction in a plan view. It has a rectangular shape. The side surface 108 and the side surface 110 face each other and extend in the main scanning direction (longitudinal direction). The side surface 112 and the side surface 114 face each other and are located at both ends in the main scanning direction. The transparent substrate 102 is disposed substantially parallel to the platen glass 46.

  The light emitting unit 100 is formed by laminating a transparent substrate, a light emitting layer, and a back electrode on the first main surface 104 of the transparent substrate 102, and an electric current is passed between the transparent electrode and the back electrode to form a planar shape. It is a planar light source that emits light. When the light emitting unit 100 emits light, light is emitted into the transparent substrate 102. Since the structure of the light emitting unit 100 of the EL element is well known, further detailed description is omitted.

  The reflecting member 116 is provided on the second main surface 106 of the transparent substrate 102 so that the reflecting surface faces the light emitting unit 100. In FIG. 2, the reflecting member 116 covers the entire surface of the second main surface 106. Accordingly, light that is about to be emitted from the second main surface 106 to the outside of the transparent substrate 102 is reflected to the inside of the transparent substrate 102 by the reflecting member 116 without being emitted to the outside of the transparent substrate 102.

  The reflection member 118 is provided on the side surface 108 of the transparent substrate 102 so that the reflection surface faces the transparent substrate 102 side. In FIG. 2, the reflecting member 118 covers the entire side surface 108. Thereby, the light that is about to be emitted from the side surface 108 to the outside of the transparent substrate 102 is reflected by the reflecting member 118 into the transparent substrate 102 without being emitted to the outside of the transparent substrate 102.

  The reflecting member 120 is provided on the side surface 112 of the transparent substrate 102 so that the reflecting surface faces the transparent substrate 102 side. In FIG. 2, the reflecting member 120 covers the entire side surface 112. As a result, light that is about to be emitted from the side surface 112 to the outside of the transparent substrate 102 is reflected by the reflecting member 120 into the transparent substrate 102 without being emitted outside the transparent substrate 102.

  The reflecting member 122 is provided on the side surface 114 of the transparent substrate 102 so that the reflecting surface faces the transparent substrate 102 side. In FIG. 2, the reflecting member 122 covers the entire side surface 114. As a result, light that is about to be emitted from the side surface 114 to the outside of the transparent substrate 102 is reflected by the reflecting member 122 into the transparent substrate 102 without being emitted outside the transparent substrate 102.

  The reflecting members 116, 118, 120, and 122 are formed by evaporating aluminum on the transparent substrate 102, for example. In addition, the reflecting members 116, 118, 120, and 122 may be formed by sticking a seal having a mirror surface to the transparent substrate 102.

  The side member 110 is not provided with a reflecting member. That is, the reflecting members 116, 118, 120, and 122 are arranged so that the reflecting surface faces the transparent substrate 102 side at least at a part (side surfaces 108, 112, 114) of the side surfaces 108, 110, 112, 114 of the transparent substrate 102. Provided. Therefore, as shown by the arrows in FIG. 2, the light emitted from the light emitting unit 100 into the transparent substrate 102 is reflected by the reflecting members 116, 118, 120, 122, and the reflecting members 116, 118, 120, 122 and The light is emitted from the portion (side surface 110) where the light emitting unit 100 is not provided to the outside of the transparent substrate 102.

  Here, the transparent substrate 102 is disposed substantially parallel to the platen glass 46 as shown in FIG. Therefore, when the side surface 110 is provided perpendicular to the first main surface 104, the light travels in the normal direction with respect to the side surface 110. That is, the light travels in the sub-scanning direction and does not irradiate the reading position A of the original P. Therefore, in the light source unit 36, the side surface 110 is inclined with respect to the second main surface 106 so as to face the platen glass 46. As a result, the light is emitted obliquely upward in FIG. 2, and the reading position A of the original P is irradiated intensively.

  As described above, according to the light source device 26 and the image reading device 3 according to the present embodiment, the first main surface 104, the second main surface 106, and the side surfaces 108, 112, 114 of the light source unit 36 are reflective members 116. , 118, 120, 122. Therefore, the light emitted from the light emitting unit 100 of the light source unit 36 is reflected by the reflecting members 116, 118, 120, and 122 and is emitted from only the side surface 110 to the transparent substrate 102. That is, light to be emitted from the first main surface 104, the second main surface 106, and the side surfaces 108, 112, 114 is concentrated and emitted from the side surface 110. As a result, as shown in the graph of FIG. 2, light having a narrow intensity distribution in the sub-scanning direction irradiates the reading position A of the original P from the light source units 36a and 36b. As a result, the combined light of the light emitted from the light source units 36a and 36b shown in the graph of FIG. 2 has an intensity distribution concentrated at the reading position A of the document P as compared with the combined light shown in FIG. That is, the light emitted from the light source units 36a and 36b can be concentrated at the reading position A of the document P, and the light use efficiency can be improved.

  Further, since the side surface 110 is inclined with respect to the second main surface 106 so as to face the platen glass 46, the light emitted from the side surface 110 travels in an obliquely upward direction in FIG. As a result, even if the light source unit 36 is disposed substantially parallel to the platen glass 46 in order to reduce the thickness of the light source device 26, the light emitted from the light source unit 36 can be applied to the reading position A of the document P. It becomes possible. That is, by inclining the side surface 110, it is possible to achieve both reduction in thickness of the light source device 26 and improvement in light utilization efficiency.

  Further, since the two light source portions 36a and 36b are provided so that the side surface 110a and the side surface 110b face each other, the light intensity distribution at the reading position A of the document P is relative to the reading position A of the document P. It becomes symmetric. Therefore, when the document P is a book, the image reading device 3 can irradiate light evenly to the joints of the pages.

(Modification)
Below, the 1st modification of the light source device 26 which concerns on 1st Embodiment is demonstrated, referring drawings. FIG. 3 is a configuration diagram of the light source device 26-1 according to the first modification, and a graph showing the intensity distribution of the light that irradiates the document P. Below, since the light source part 36-1a and the light source part 36-1b have the same structure, a and b after a reference sign are abbreviate | omitted and the structure of the light source part 36-1 is demonstrated.

  The difference between the light source device 26 and the light source device 26-1 is that, in the light source device 26, the first main surface 104 and the second main surface 106 of the transparent substrate 102 are parallel to each other. −1 is that the first main surface 104-1 and the second main surface 106-2 of the transparent substrate 102-1 are not parallel. Therefore, this difference will be described.

  As shown in FIG. 3, in the light source unit 36-1, the distance between the first main surface 104-1 and the second main surface 106-1 increases as the distance from the side surface 110-1 approaches in the sub-scanning direction. It has become. As described above, by arranging the first main surface 104-1 and the second main surface 106-1, the light emitted from the light emitting unit 100-1 and the light reflected by the reflecting member 116-1 are as follows. As shown by the arrow in FIG. 3, it becomes easier to proceed toward the side surface 110-1. As a result, more light is emitted from the side surface 110-1, and the intensity of the light that irradiates the reading position A of the document P becomes stronger as shown in the graph of FIG.

  Since the other configuration of the light source unit 36-1 is the same as that of the light source unit 36, the description thereof is omitted.

  Next, a second modification of the light source device 26 according to the first embodiment will be described with reference to the drawings. FIG. 4 is a configuration diagram of the light source device 26-2 according to the second modification, and a graph showing the intensity distribution of the light that irradiates the document P. In the following, since the light source unit 36-2a and the light source unit 36-2b have the same configuration, the configuration of the light source unit 36-2 will be described by omitting a and b after the reference numerals.

  The difference between the light source device 26 and the light source device 26-2 is that light is emitted from the side surface 110 in the light source device 26, whereas in the light source device 26-2, the light is emitted from the second main surface 106-2. This is the point where light is emitted. Therefore, this difference will be described.

  As shown in FIG. 4, in the light source part 36-2, the reflection member 119-2 is provided so that the side surface 110-2 may be covered. This prevents light from being emitted from the side surface 110-2 to the outside of the transparent substrate 102-2. Instead, in the light source unit 36-2, the reflecting member 116-2 is not provided on a part of the second main surface 106-2. Light is emitted from the portion of the second main surface 106-2 where the reflecting member 116-2 is not provided to the outside of the transparent substrate 102-2.

  Also in the light source device 26-2 as described above, a part of the second main surface 106-2 and the light to be emitted from the side surfaces 108-2, 110-2, 112-2, 114-2 are The main surface 106-2 is concentrated and emitted from a portion where the reflecting member 116-2 is not provided. As a result, the light source unit 36-2 can improve the light use efficiency in the same manner as the light source unit 36 shown in FIG.

(Second Embodiment)
Hereinafter, a light source device and an image reading device according to a second embodiment of the present invention will be described with reference to the drawings. The configuration of the image reading apparatus according to the present embodiment is different from the configuration of the image reading apparatus 3 shown in FIG. 1 only in the configuration within the light source device 26. Therefore, the configuration of the light source device 26-3 according to the second embodiment will be described below with reference to the drawings. FIG. 5 is a configuration diagram of the light source device 26-3 according to the second embodiment and a graph showing the intensity distribution of the light that irradiates the document P.

  As illustrated in FIG. 5, the light source device 26-3 includes a light source unit 36-3, a first mirror 38, and a reflecting member 140. The first mirror 38 in FIG. 5 is the same as the first mirror 38 in FIG.

  The first difference between the light source device 26 shown in FIG. 2 and the light source device 26-3 shown in FIG. 5 is that, in the light source unit 36, the entire side surface 110 is inclined with respect to the second main surface 106. On the other hand, in the light source unit 36-3, the inclined surface 142-3 that is inclined with respect to the second main surface 106 so as to face the platen glass 46, and the vertical surface that is perpendicular to the first main surface 104. 144-3 is included in the side surface 110. Further, the second difference between the light source device 26 shown in FIG. 2 and the light source device 26-3 shown in FIG. 5 is that the light source device 26 shown in FIG. In the light source device 26-3 shown in FIG. 5, the light source unit 36-3 and the reflecting member 140 facing the vertical surface 144-3 are provided.

  Since the side surface 110 includes the inclined surface 142-3 and the vertical surface 144-3, light is emitted from the inclined surface 142-3 toward the reading position A of the document P, and from the vertical surface 144-3. Then, light is emitted toward the reflecting member 140. The reflecting member 140 reflects the light emitted from the vertical surface 144-3 toward the platen glass 46 side. Thereby, light is irradiated to the reading position A of the document P from the two directions of the light source unit 36-3 side and the reflecting member 140 side.

  According to the light source device 26-3 as described above, a part of the light emitted from the light source unit 36-3 directly irradiates the reading position A of the document P, and the remaining light emitted from the light source unit 36-3. Is reflected by the reflecting member 140 and irradiates the reading position A of the original P. Therefore, the light source device 26-3 can irradiate the reading position A of the document P from two directions by one light source unit 36-3.

(Modification)
Below, the 1st modification of the light source device 26-3 which concerns on 2nd Embodiment is demonstrated, referring drawings. FIG. 6 is a configuration diagram of the light source device 26-4 according to the first modification and a graph showing the intensity distribution of the light that irradiates the document P.

  The first difference between the light source device 26-3 and the light source unit 26-4 is that, in the light source device 26-3, the transparent substrate 102-3 and the platen glass 46 are parallel to each other, whereas the light source device 26. 4, the transparent substrate 102-4 is inclined with respect to the platen glass 46 so as to face the reading position A side of the document P.

  Further, the second difference is that in the light source device 26-3, the side surface 110-3 is not provided with a reflecting member, whereas in the light source device 26-4, the side surface 110-4 has a reflecting member 119-. There is a difference in that 4 is provided. Furthermore, in the light source device 26-4, as shown in FIG. 6, a reflection member 116-4 is provided on the second main surface 106-4 with a gap from the side surfaces 108-4 and 110-4. . Hereinafter, the gap between the side surface 108-4 and the reflecting member 116-4 in the second main surface 106-4 is referred to as a gap 146-4, and the side surface 110-4 and the reflecting member in the second main surface 106-4. The gap between 116-4 is referred to as a gap 148-4. The width L1 of the gap 146-4 in the sub-scanning direction and the width L2 of the gap 148-4 in the sub-scanning direction are equal as shown in FIG.

  As in the light source unit 36-4, the reflecting member 116-4 is provided in the second main surface 106-4 with the gaps 146-4 and 148-4 spaced from the side surfaces 108-4 and 110-4. As a result, light is emitted from the gaps 146-4 and 148-4. Here, the transparent substrate 102-4 is inclined with respect to the platen glass 46 so as to face the reading position A side of the document P. Therefore, the light emitted from the gap 146-4 directly irradiates the reading position A of the document P. On the other hand, the light emitted from the gap 148-4 travels toward the reflecting member 140 provided to face the second main surface 106-4. The reflecting member 140 reflects light toward the platen glass 46 side. As a result, the light is irradiated from the two directions of the light source unit 36-4 side and the reflection member 140 side with respect to the reading position A of the document P.

  According to the light source device 26-4 as described above, a part of the light emitted from the light source unit 36-4 directly irradiates the reading position A of the document P, and the remaining light emitted from the light source unit 36-4. Is reflected by the reflecting member 140 and irradiates the reading position A of the original P. Therefore, the light source device 26-4 can irradiate the reading position A of the document P from two directions by one light source unit 36-4.

  In FIG. 6, when there is no reflecting member 116-4, the light emitted from the center portion of the second main surface 106-4 does not irradiate the reading position A of the original P, and other than the original P. Irradiate the part. Therefore, the reflection member 116-4 is provided in the central portion of the second main surface 106-4, so that light that is about to be emitted from the central portion of the second main surface 106-4 is reflected in the reflection member 116-4. The light is reflected and emitted from the gap 146-4 or the gap 148-4. Thereby, the light which is going to be emitted from the central portion of the second main surface 106-4 is also irradiated to the reading position A of the document P, and the light use efficiency is improved in the light source unit 36-4.

  Next, a second modification of the light source device 26-3 according to the second embodiment will be described with reference to the drawings. FIG. 7 is a configuration diagram of the light source device 26-5 according to the second modification and a graph showing the intensity distribution of the light irradiating the document P.

  The difference between the light source device 26-4 shown in FIG. 6 and the light source device 26-5 shown in FIG. 7 is that the light source device 26-4 has a width L1 in the sub-scanning direction of the gap 146-4 and a sub-space of the gap 148-4. Although the width L2 in the scanning direction is equal, in the light source device 26-5, the width L1 of the gap 146-5 in the sub-scanning direction is smaller than the width L2 of the gap 148-5 in the sub-scanning direction.

  According to the light source device 26-5 as described above, the intensity of light that irradiates the reading position A of the document P from the light source unit 36-5 side and the intensity of light that irradiates the reading position A of the document P from the reflection member 140 side. Can be equal. This will be described below.

  In the light source device 26-4, as shown in the graph of FIG. 6, the intensity of light irradiated from the light source unit 36-4 side and the intensity of light irradiated from the reflecting member 140 side are different for the reasons described below. It was. As shown in FIG. 6, the transparent substrate 102-4 of the light source unit 36-4 is inclined with respect to the platen glass 46. Therefore, the distance from the gap 146-4 to the reading position A of the original P is shorter than the distance from the gap 148-4 to the reading position A of the original P. As a result, the light emitted from the gap 148-4 is attenuated more than the light emitted from the gap 146-4. That is, when the intensity of the light emitted from the gap 146-4 is equal to the intensity of the light emitted from the gap 148-4, the intensity of the light that irradiates the reading position A of the document P from the light source unit 36-4 side. However, the intensity of the light irradiating the reading position A of the original P from the reflecting member 140 side becomes stronger.

  Therefore, in the light source device 26-5, the width L1 of the gap 146-5 in the sub-scanning direction is made smaller than the width L2 of the gap 148-5 in the sub-scanning direction. Thereby, the intensity of the light emitted from the gap 148-5 becomes stronger than the intensity of the light emitted from the gap 146-5. The light emitted from the gap 148-5 is attenuated to a greater extent than the light emitted from the gap 146-5. Therefore, at the reading position A of the original P, the intensity of the light emitted from the light source unit 36-5 side and the reflecting member 140 side. The intensity of the light irradiated from is equal.

  The light emitting units 100-1 to 100-5 are organic EL elements, but the light emitting units 100-1 to 100-5 may be inorganic EL elements.

  Although the light source devices 26, 26-1, 26-2, 26-3, 26-4, and 26-5 are the first sliders for the sake of convenience, they do not necessarily have to be the first sliders. That is, the light source devices 26, 26-1, 26-2, 26-3, 26-4, and 26-5 include the light source units 36a, 36b, 36-1a, 36-1b, 36-2a, 36-2b, 36. What is necessary is just a component including -3, 36-4, 36-5 and the reflective member 140.

1 is a configuration diagram of a copying machine including an image reading apparatus according to a first embodiment. FIG. 2 is a configuration diagram of a light source device according to the first embodiment and a graph showing an intensity distribution of light that irradiates a document. It is the block diagram which showed the block diagram of the light source device which concerns on a 1st modification, and the intensity distribution of the light which irradiates a document. It is the block diagram which showed the block diagram of the light source device which concerns on a 2nd modification, and the intensity distribution of the light which irradiates a document. It is the block diagram which showed the block diagram of the light source device which concerns on 2nd Embodiment, and the intensity distribution of the light which irradiates a document. It is the block diagram which showed the block diagram of the light source device which concerns on a 1st modification, and the intensity distribution of the light which irradiates a document. It is the block diagram which showed the block diagram of the light source device which concerns on a 2nd modification, and the intensity distribution of the light which irradiates a document. 6 is a configuration diagram of a light source device of a document reading device described in Patent Document 1, and a graph showing light intensity distribution in the light source device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Copier 2 Original conveying apparatus 3 Image reading device 26, 26-1, 26-2, 26-3, 26-4, 26-5 Light source device 36a, 36b, 36-1a, 36-1b, 36-2a, 36-2b, 36-3, 36-4, 36-5 Light source part 44, 46 Platen glass 100a, 100b, 100-1a, 100-1b, 100-2a, 100-2b, 100-3, 100-4, 100-5 Light Emitting Units 102a, 102b, 102-1a, 102-1b, 102-2a, 102-2b, 102-3, 102-4, 102-5 Transparent Substrate 104a, 104b, 104-1a, 104-1b, 104-2a, 104-2b, 104-3, 104-4, 104-5 First main surface 106a, 106b, 106-1a, 106-1b, 106-2a, 106-2b, 06-3, 106-4, 106-5 Second main surface 108a, 108b, 108-1a, 108-1b, 108-2a, 108-2b, 108-3, 108-4, 108-5, 110a, 110b, 110-1a, 110-1b, 110-2a, 110-2b, 110-3, 110-4, 110-5, 112a, 112-4, 112-5, 114a, 114-4, 114-5 116a, 116b, 116-1a, 116-1b, 116-2a, 116-2b, 116-3, 116-4, 116-5, 118a, 118b, 118-1a, 118-1b, 118-2a, 118- 2b, 118-3, 118-4, 118-5, 119-2a, 119-2b, 119-4, 119-5, 120a, 120-4, 120-5, 122a, 122 4,122-5,140 reflecting member 142-3 inclined surface 144-3 vertical plane 146-4,146-5,148-4,148-5 clearance A reading position P document

Claims (12)

In a light source device that is used in an image reading device and irradiates light on a document
A transparent substrate comprising a first main surface, a second main surface and side surfaces;
A planar light source provided on the first main surface;
A first reflecting member provided on the second main surface so that a reflecting surface faces the planar light source;
With
The light emitted from the planar light source into the transparent substrate is emitted out of the transparent substrate from a portion where the first reflecting member and the planar light source are not provided;
A light source device characterized by the above. The first reflecting member covers the entire surface of the second main surface;
The light source device according to claim 1. In at least a part of the side surface of the transparent substrate, a second reflecting member provided so that the reflecting surface faces the transparent substrate side,
To provide further,
The light source device according to claim 2. The image reading device includes a transparent plate for placing a document,
The transparent substrate is disposed substantially parallel to the transparent plate,
Of the side surfaces, the side surface on which the second reflecting member is not provided is inclined with respect to the second main surface so as to face the transparent plate,
The light source device according to claim 3. Of the side surfaces, the side surface on which the second reflecting member is not provided is
An inclined surface inclined with respect to the second main surface so as to face the transparent plate;
A vertical plane perpendicular to the first main surface;
Including
A third reflecting member facing the vertical surface;
In addition,
The light emitted from the vertical surface to the outside of the transparent substrate is reflected by the third reflecting member toward the transparent plate;
The light source device according to claim 4. An interval between the first main surface and the second main surface is increased as approaching a side surface on which the second reflecting member is not provided;
The light source device according to any one of claims 3 to 5, wherein: The transparent substrate has a rectangular shape when viewed in plan,
The side surface of the transparent substrate includes a first side surface and a second side surface extending in the longitudinal direction,
The first reflecting member is provided on the second main surface with a gap from the first side surface and the second side surface,
The light source device according to claim 1. The image reading device includes a transparent plate for placing a document,
The transparent substrate is disposed to be inclined with respect to the transparent plate,
A fourth reflecting member facing the second main surface;
In addition,
Light emitted from the gap between the first reflecting member and the second side surface to the outside of the transparent substrate is reflected toward the transparent plate by the fourth reflecting member;
The light source device according to claim 7. The width of the gap between the first side surface and the first reflecting member is smaller than the width of the gap between the second side surface and the first reflecting member;
The light source device according to claim 8. The light source device according to any one of claims 1 to 9,
Preparing,
An image reading apparatus characterized by the above. The light source device is movable in parallel with the document;
The image reading apparatus according to claim 10. Conveying means for conveying the document on the light source device,
To provide further,
The image reading apparatus according to claim 10 or 11, wherein:

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