JPH10243166A - Image reader, light guide member used for it and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance the quality of a read image by avoiding a disadvantage of an undesired large size from being caused to each section of the image reader such as employment of a thick cover glass plate for an image read face to the utmost so as to uniformize the illuminance of the image read face in a read line longitudinal direction in the case of using a light guide member that scatters a light from a light source into strips so as to read an image of a desired image read object. SOLUTION: An image reader is provided with a light source 3, a 1st light guide member 1 that scatters a light made incident from the light source 3 into the inside and emits the light from an entire length area of a 1st optical emission face 12 with a prescribed length, and a light receiving element 52 for reading an image, and a 2nd light guide member 2 made of a transparent member through which a light made incident onto the inside from the 1st light emission face 12 propagated through a prescribed path is emitted from nearly all areas of a 2nd light emission face 22 having a prescribed length, and the 2nd light emission face 22 is formed to be an image read face which is in contact with an image read object from which an image is read by the light receiving element 25.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image reading device such as a contact type image sensor, a light guide member used in the image reading device, and a manufacturing method for manufacturing the light guide member.

[0002]

2. Description of the Related Art Conventionally, as an example of an image reading apparatus, there is one disclosed in Japanese Patent Application Laid-Open No. 6-217084. As shown in FIG. 21 of the present application, the conventional image reading surface 90 is provided inside a case 4e to which a cover glass 91 forming an image reading surface 90 is attached.
And a light receiving element 52e for receiving the light focused by the lens 51e. Case 4 above
A linear light source device B for irradiating the image reading surface 90 with light is also accommodated inside e. The linear light source device B
As shown in FIG. 22 (a), a light guide member 1e made of a transparent member having a fixed length, and a light source 3e (point light source) arranged on one side in the longitudinal direction of the light guide member 1e. ). The light guide member 1e has one side surface 12e extending in the longitudinal direction as a light emitting surface, and one end surface 15e of a longitudinal end portion as a light incident portion facing the light source 3e. The light 3e is emitted and enters the light guide member 1e, and travels in the longitudinal direction, and exits from each part of the light exit surface 12e to the outside. The side surface 14e facing the light exit surface 12e is a light diffuse reflection surface.

According to the image reading device having the above-described structure, light can be emitted from substantially the entire length of the light exit surface 12e having a fixed length of the light guide member 1e. It is possible to irradiate light in a strip shape extending in the longitudinal direction of the reading line, and it is possible to read the image of the original G having a certain width line by line. In addition, since the linear light source device B emits light emitted from the point light source 3e in a longitudinal direction of the image reading surface 90, the number of the light sources 3e is reduced to a small number or a minimum number. For example, the necessity of arranging a large number of point light sources such as LEDs at regular intervals along the longitudinal direction of the image reading surface can be eliminated.

[0004]

However, the conventional image reading apparatus has the following problems to be solved.

First, in the above-described conventional image reading apparatus, the outer surface of a cover glass 91 is used as an image reading surface 90, and a platen roller 9 for transferring a document G, for example, is pressed against the cover glass 91. Therefore, the cover glass 91 needs to have sufficient strength against the roller pressure. Further, when the image reading device is configured as a so-called handy scanner, the cover glass 91 is directly exposed to the outside, so that various articles may come into contact with or collide with the surface. Therefore, when the image reading device is configured as a handy scanner, the cover glass 9
It is necessary to increase the strength of No. 1 in particular. Conventionally, in order to satisfy such requirements, the thickness of the cover glass 91 must be considerably increased.

However, since the cover glass 91 is only a member that plays the role of forming the image reading surface 90, even if the thickness of the cover glass 91 is increased,
That in itself does not create any new functions or added value. Increasing the thickness of the cover glass 91 only results in an increase in the size and weight of parts and an increase in manufacturing cost, and it is necessary to eliminate such disadvantages.

Second, in the above-described conventional image reading apparatus, in order to properly read the image of the original G line by line, it is required to make uniform the illuminance in the longitudinal direction of the reading line on the image reading surface 90. You. If there is a large variation in the illuminance in the longitudinal direction of the reading line, the read image obtained by using the light receiving element 52e has a shading difference that cannot be seen in the actual image of the original G. This is because, in the case of a document, the color tone of the read image is significantly different from the color tone of the actual document, and the quality of the read image deteriorates.

However, in the linear light source device B used in the above-mentioned conventional image reading device, the amount of light emitted from the entire length of the light exit surface 12e of the light guide member 1e is not uniform, and is not uniform. As shown in (b), the amount of light emitted from the light emitting surface 12e is maximum in the vicinity of the light source 3e and decreases as the distance from the light source 3e increases. Therefore, in the related art, it is difficult to make the illuminance in the longitudinal direction of the reading line of the image reading surface 90 uniform at various places by simply irradiating the image reading surface 90 with the linear light source device B. Was.

On the other hand, in the above-described conventional image reading apparatus, in order to make the illuminance uniform, the linear light source device B is required.
It is desired that the optical distance L from the light guide member 1 e to the image reading surface 90 be as large as possible by making the image reading surface 90 far away from the image reading surface 90. When the linear light source device B is brought close to the image reading surface 90, the variation in the amount of light emitted from the light guide member 1e appears on the image reading surface 90 as it is, whereas the linear light source device B
Is separated from the image reading surface 90, such a variation can be reduced to some extent.
However, conventionally, the light exit surface 1 of the light guide member 1e has
In order to increase the optical distance, it is necessary to provide a large space between the light guide member 1e and the image reading surface 90 because the light receiving member 2e is merely provided to face the image reading surface 90. And the size of the entire image reading apparatus, especially the size in the thickness direction, becomes very large. For this reason, in the related art, there is a certain limit in making the illuminance uniform in the longitudinal direction of the reading line on the image reading surface 90 by increasing the optical distance, and it is difficult to improve the quality of the read image. Had become.

The present invention has been conceived under such circumstances, and reads an image of a desired image reading object by using a light guide member that disperses light emitted from a light source in a band shape. In such a case, the illuminance of the image reading surface in the longitudinal direction of the reading line is minimized by minimizing a problem that each part of the image reading device becomes unnecessarily large, such as forming the image reading surface using a thick cover glass. It is an object of the present invention to improve the quality of a read image by making the image uniform.

[0011]

DISCLOSURE OF THE INVENTION In order to solve the above problems, the present invention employs the following technical means.

That is, according to a first aspect of the present invention, there is provided an image reading apparatus. The image reading apparatus includes a light source, a first light guide member for dispersing light incident inside from the light source in a band shape, and emitting the light from a substantially entire length of a first light emitting surface having a fixed length, and an image reading device. And a light receiving element, wherein the second light having a certain length is formed by advancing light incident from the first light emitting surface of the first light guide member to the inside through a predetermined path. A second member made of a transparent member capable of emitting light from substantially the entire length area of the emission surface;
A light guide member, and a second light guide member of the second light guide member.
The light emitting surface is characterized in that it is an image reading surface for bringing an image reading object, from which an image is read by the light receiving element, into opposing contact.

In the present invention, the second light guide member may be made of glass or synthetic resin. When the second light guide member is made of glass, the wear resistance of the image reading surface can be improved, and its transparency can be increased to improve the light transmission efficiency. On the other hand, when the second light guide member is made of a synthetic resin, the manufacture thereof is facilitated, the manufacturing cost can be reduced, and the weight can be reduced.

In the present invention, when the light source emits light, the light emitted from the light source is dispersed in a band shape by the first light guide member and is emitted from the first light exit surface of the first light guide member. Then, the light emitted from the first light emitting surface enters the inside of the second light guide member, travels along a predetermined path, and exits from the substantially entire region of the second light emitting surface having a fixed length. It will be. On the other hand, in the present invention, the second light emitting surface is an image reading surface.
If the object to be read is brought into contact with the light emitting surface, the object to be read can be illuminated in a strip shape, and the light reflected by the object to be read is received by the light receiving element to form the image. Can be read.

According to the present invention, the second light guide member having the second light guide member which exhibits the function of guiding the light emitted from the first light guide member through a predetermined path.
The light emitting surface is an image reading surface, and the second light guide member also serves as a conventionally used cover glass. Therefore, unlike the related art, there is no need to use a dedicated cover glass for forming the image reading surface, which is reasonable. Moreover, in the present invention, by using a transparent member having an appropriate thickness as the second light guide member, its strength can be sufficiently and easily increased, and the pressure of the platen roller and the contact with other articles can be reduced. The effect of being able to make it difficult to be easily damaged due to a collision or the like is obtained. The handy scanner type image reading device has a high possibility that various articles or other things come into contact with or collide with the image reading surface,
Since the strength of the image reading surface is more required, the present invention is more suitable when configured as such a handy scanner.

Further, as an important effect, in the present invention, the light emitted from the first light emitting surface of the first light guide member is not directly radiated to the image reading surface, but is emitted from the first light emitting surface. Since the light travels along the fixed path in the second light guide member, the optical distance from the first light exit surface of the first light guide member to the image reading surface is changed by the optical path of the second light guide member. It can be lengthened by minutes. If the optical distance is increased in this manner, light is emitted from the first light exit surface of the first light guide member without providing a very large space between the first light guide member and the image reading surface. Variations in the amount of light can be reduced before the light is guided to the image reading surface, and there is an advantage that the illuminance in the longitudinal direction of the reading line on the image reading surface can be made uniform.

In a preferred embodiment of the present invention, the second light guide member has a plurality of outer peripheral side surfaces extending in the longitudinal direction of the second light guide member, and the second light guide member has a plurality of outer peripheral side surfaces. The entirety or a part of one side surface is the second light emitting surface, and a part of the second side surface facing the first side surface in the thickness direction is desired from the second light emitting surface. An image light emission surface for irradiating the image reading target with light reflected inside the second light guide member to the outside of the second light guide member is provided, and the light receiving element includes: The light emitted from the image light emission surface is provided so as to be able to receive light.

According to such a configuration, when light is irradiated from the second light exit surface to the object to be read, which is disposed opposite to the second light exit surface of the second light guide member, the light is emitted. The light is reflected toward the inside of the second light guide member by the image reading object. Then, this light is thereafter emitted from the image light emission surface of the second side surface of the second light guide member to the outside of the second light guide member, and is received by the light receiving element.
Therefore, the image of the image reading object arranged opposite to the second light emitting surface can be appropriately read by the light receiving element.

In another preferred embodiment of the present invention,
In the second light guide member, a region other than the image light emission surface or a part of the second side surface causes light to enter the second light guide member from the first light guide member. A third side surface and a fourth side surface of the plurality of outer peripheral side surfaces, which are opposed to each other in the width direction of the second light guide member, enter the second light guide member from the light incident portion. The reflected light is an inclined light reflecting surface that is sequentially reflected so as to guide the light to the second light emitting surface.

According to such a configuration, the light emitted from the first light exit surface of the first light guide member enters the second light guide member from the light incident portion on the second side surface of the second light guide member. Then, the light is sequentially reflected by the third side surface and the fourth side surface of the second light guide member, and is guided to the second light emission surface. Therefore, the light emitted from the light source is
The light guide member and the second light guide member can be appropriately guided to a predetermined position of the second light guide member.

In another preferred embodiment of the present invention,
A case capable of accommodating the light source, the first light guide member, the second light guide member, and the light receiving element therein, and an outer surface of one side of the case and a second light emission of the second light guide member The surface is substantially flush.

According to such a configuration, each of the light source, the first light guide member, the second light guide member, and the light receiving element can be accommodated in one case, and the entire apparatus can be assembled compactly. Also, the second image reading surface
Since the light emitting surface and the outer surface of one side of the case are substantially flush with each other, when a document to be read, for example, is placed on the second light emitting surface, the document is placed on the case or the second guide. It is possible to make it difficult for the optical member to be caught by the optical member, and to improve the usability when reading an image.

In another preferred embodiment of the present invention,
A case in which the light source, the first light guide member, the second light guide member, and the light receiving element can be housed; and a case in which the first light guide member and the second light guide member are housed in the case. First
One or more fittings that can be fitted into a void formed outside the first light guide member and the second light guide member in the case so that the light guide member and the second light guide member are positioned and held. A fixing member.

According to such a configuration, not only can the predetermined components of the image reading apparatus be housed in the case to make the entire apparatus compact, but also, by arranging the fixing member at a predetermined position in the case, it is possible to reduce the size of the image reading apparatus. Since the positioning and fixing of the first light guide member and the second light guide member can be achieved, the work of assembling the first light guide member and the second light guide member to the case is facilitated. Needless to say, by positioning and fixing the first light guide member and the second light guide member, the relative positional relationship between the first light guide member and the light source and the second light guide member serving as an image reading surface can be obtained. Inadvertent misalignment of the position of the two light emission surfaces can be prevented, and a desired image reading operation can be accurately performed.

In another preferred embodiment of the present invention,
Of the outer peripheral side surface of the second light guide member, the first side surface on which the second light emitting surface is formed has a step surface in which a part of the first side surface is recessed from the second light emitting surface. A step portion is provided, and the fixing member is provided with a protruding piece portion that faces the step surface so as to prevent the second light guide member from being removed when the second light guide member is accommodated in the case. Have been.

According to such a configuration, when positioning and fixing the second light guide member using the fixing member, the projecting piece of the fixed member is provided on the first side surface of the second light guide member. When the second light guide member is brought into face-to-face contact with the stepped surface, the movement of the second light guide member in the thickness direction can be restricted, and the second light guide member can be prevented from coming off the case. Also, the step surface where the protruding piece portion is in face-to-face contact,
Since the portion is recessed from the second light emission surface, the outer surface of the protruding piece and the second light emission surface can be set to be substantially flush. Therefore, when a document or the like to be image-read is arranged facing the second light exit surface, it is possible to eliminate the possibility that the document may be caught on the protruding portion.

In another preferred embodiment of the present invention,
A light reflecting member is interposed between each of the outer surfaces of the first light guiding member and the second light guiding member and the fixing member.

According to such a configuration, it is possible to prevent the light passing through the first light guide member and the second light guide member from leaking to the outside of the light guide member by the light reflection member. it can. Therefore, the efficiency of light irradiation on the object to be read can be improved.

According to a second aspect of the present invention, there is provided a light guide member. The light guide member is a light guide member made of a transparent member having a plurality of planar outer peripheral side surfaces extending in a certain direction, and the plurality of outer peripheral side surfaces is a first member facing the thickness direction of the light guide member. There are a side surface and a second side surface, and a third side surface and a fourth side surface opposed to each other in the width direction of the light guide member, and the third side surface is inclined so as to be opposed to a partial region of the second side surface. It is characterized in that the fourth side surface is an inclined surface that is inclined so as to face a partial region of the first side surface.

In the present invention, when light is made to enter the inside of the light guide member from a predetermined partial area on the second side surface of the light guide member in the thickness direction, the light is made to face the second side surface. The light reaches the inclined third side surface, is reflected, and travels in the direction of the fourth side surface that faces the third side surface in the thickness direction. Then, the light is thereafter reflected by the fourth side surface, travels in the direction of a partial region of the first side surface facing the fourth side surface, and is emitted to the outside from the partial region of the first side surface. . Therefore, this light guide member can be appropriately used as the second light guide member of the image reading device provided by the first aspect of the present invention.

According to a third aspect of the present invention, there is provided a method of manufacturing a light guide member. The method of manufacturing this light guide member is as follows:
It is a manufacturing method of a light guide member for manufacturing a light guide member provided from the glass sheet provided by the second aspect of the present invention, wherein the light guide member has one of a third side surface and a fourth side surface. Using a first cutting blade having correspondingly shaped blades on both sides to sequentially cut a sheet glass wider than the light guide member at a predetermined pitch; and a third side and a fourth side of the light guide member. A step of further cutting a widthwise intermediate portion of the plate glass cut by the first cutting blade using a second cutting blade having a blade portion having a shape corresponding to the other cross-sectional shape of the side surface on both surfaces; And having the following.

In the present invention, when the sheet glass is first cut by the first cutting blade, both sides of the cut portion have the same cross-sectional shape as the third side surface (or the fourth side surface) of the light guide member. The sheet glass sequentially cut at a predetermined pitch by the first cutting blade has side surfaces at both ends in the width direction each serving as a third side surface (or a fourth side surface). Next, when the intermediate portion of the plate glass is cut by a second cutting blade and divided into two portions, both side portions of the cut portion have the same cross-sectional shape as the fourth side surface (or the third side surface) of the light guide member. , 2 above
Each of the divided plate glass cut pieces is a transparent member having one end in the width direction serving as the third side surface of the light guide member and the other end serving as the fourth side surface. The two surfaces facing the thickness direction of the cut piece of plate glass correspond to the first side surface and the second side surface of the light guide member. Therefore, according to the above manufacturing method, a large number of light guide members provided by the second aspect of the present invention can be efficiently manufactured from one sheet of glass by a simple operation process.

[0033]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be specifically described below with reference to the drawings.

FIG. 1 is a sectional view of an essential part showing an example of an image reading apparatus A according to the present invention. FIG. 2 shows X1 of FIG.
It is -X1 sectional drawing. FIG. 3 is a sectional view taken along line X2-X2 of FIG. FIG. 4 is a sectional view showing a state in which the image reading device A shown in FIG. 1 is assembled. FIG. 5 is an exploded perspective view of the image reading device A shown in FIG.

As shown in FIG. 5, the image reading device A includes a case 4, a circuit board 6, a large number of light receiving elements 52 mounted on the circuit board 6, and a set of three LEs.
D (3A to 3C), lens array 51, first light guide member 1, second light guide member 2, first light reflection plate 8A, second light reflection plate 8B, first fixing member 7A, second fixing member 7B. , And 1
Alternatively, it is provided with a plurality of attachments 69. In the image reading device A, as described later,
Part of the area of the second light guide member 2 is used as an image reading surface, and light emitted from the LED 3 is transmitted to the first light guide member 1.
Further, by traveling inside the second light guide member 2, the light reaches the image reading surface, and the reflected light is received by the light receiving element 52.

The case 4 is made of, for example, a synthetic resin, and is formed in an elongated box shape in which substantially the entire upper surface is opened and an opening is appropriately provided in the bottom. Each of the above-described components constituting the image reading apparatus A is accommodated in the case 4. In this case 4
When the image reading device A is configured as a handy scanner, the image reading device A can also function as a housing of the handy scanner for the user to hold by hand.

FIG. 6 is a front view of the first light guide member 1. FIG. 7 is a plan view of the first light guide member 1. FIG.
FIG. 7 is a sectional view taken along line X3-X3 of FIG. FIG.
It is 4-X4 sectional drawing.

The first light guide member 1 is made of, for example, PMMA
The first transparent member 10 obtained by molding an acrylic transparent resin such as that described above occupies the main part. The first light guide member 1 is an elongated bar having a certain dimension in the longitudinal direction, and has a first side surface 10A and a second side surface 10 extending in the longitudinal direction.
B, a third side surface 10C, a fourth side surface 10D, and end surfaces 10E and 10F at both ends in the longitudinal direction. The first side surface 10A and the second side surface 10B oppose each other in the vertical thickness direction, and preferably, the width of the first side surface 10A is smaller than the width of the second side surface 10B. The third above
The side surface 10C and the fourth side surface 10D face each other in the width direction of the first light guide member 1.

The first side surface 10A is, as described later,
The entire length region is a portion serving as the first light emitting surface 12, and is preferably a mirror-like plane. Similarly, the third side surface 10C and the fourth side surface 10D are also mirror-like planes. It should be noted that the mirror-like plane does not necessarily need to be a plane whose surface is actively polished. For example, when the first light guide member 1 is resin-molded using a mold, a relatively smooth surface obtained by the resin molding is also included in the mirror-like plane. If the surface of the transparent member is a mirror-like flat surface, it is possible to totally reflect all light rays incident on the surface at an angle larger than the critical angle for total reflection specified by the material of the transparent member, and Light rays incident at an angle smaller than the critical angle for total reflection can be transmitted.

At the center in the longitudinal direction of the first side surface 10A, there is provided a substantially V-shaped concave portion 11 as viewed from the front. The recess 11 forms two inclined surfaces 11a, 11a, and these two inclined surfaces 11a, 11a are also mirror-like. As shown in FIG. 10, each of the inclined surfaces 11 a causes light emitted from the LED 3 and incident on the inside of the first light guide member 1 to travel toward both ends in the longitudinal direction of the first light guide member 1. In this embodiment, it is a part that plays a role of reflecting, and in this embodiment, a surface that is a curved surface and that can totally reflect light emitted from the LED 3 as a point light source disposed at a predetermined position is connected in series. The surface is equal to

A concave portion 16 is formed in the center of the second side surface 10B in the longitudinal direction, and the portion where the concave portion 16 is formed is the first light incident portion 15. The recess 16 is
It is a size that allows the LED 3 to be placed inside,
The cross section has a substantially trapezoidal shape that becomes narrower as it goes to the back so as to facilitate insertion positioning of the ED 3. The recess 16 faces the center of the recess 11.

A plurality of concave portions 14 are provided at appropriate intervals in a region of the second side surface 10B other than the first light incident portion 15. The region between the plurality of concave portions 14 is a mirror-shaped flat portion 13. The plurality of concave portions 14 are portions that play a role of rapidly changing a traveling angle of light traveling inside the first light guide member 1 and emitting the light from the first side surface 10A, and have, for example, an arc-shaped cross section. It has a curved inclined surface 14a. The second side surface 10B is formed as an inclined surface that gradually reduces the thickness of the first light guide member 1 from the center in the longitudinal direction to both ends in the longitudinal direction. If the second side surface 10B is formed as such an inclined surface, light traveling from the central portion in the longitudinal direction of the first light guide member 1 to both ends in the longitudinal direction is transmitted to the inclined surface 1B.
4a can be efficiently incident, which is preferable. However, the present invention is not limited to this, and the second side surface 10B may be a surface substantially parallel to the first side surface 10A.

The third side surface 10C is provided with a plurality of holes 18 at appropriate intervals in the longitudinal direction.
The plurality of holes 18 are portions for fitting the protrusions 71 of the second fixing member 7B, as described later, and are used to attach the second fixing member 7B to the first light guide member 1. You. Each of the plurality of holes 18 preferably has a long hole shape that is long in the longitudinal direction of the first light guide member 1. With such a long hole shape, the plurality of holes 18
Even when the first light guide member 1 and the projection 71 of the second fixing member 7B are slightly displaced in the longitudinal direction, they can be fitted to each other.

The first light guide member 1 plays a role of dispersing the light emitted from the LED 3 into a band shape and then emitting the light from the entire length of the first side surface 10 A as the first light emitting surface 12. Specifically, as shown in FIG. 10, when the LED 3 emits light in a state where the LED 3 is arranged in the concave portion 16, the light is transmitted from the first light incident portion 15 into the first light guide member 1. It enters with an appropriate spread angle. Most of the light reaches the two inclined surfaces 11a, 11a facing the first light incident portion 15. However, since these inclined surfaces 11a, 11a are inclined with respect to the longitudinal direction of the first light guide member 1, these inclined surfaces 11a are removed from the LED 3.
The incident angle of light that directly reaches the first and the second transparent members 10a and 11a can be made larger than a predetermined total reflection critical angle specified by the material of the first transparent member 10. Therefore, the first light guide member 1
Most of the light incident inside is prevented from passing through the inclined surfaces 11a and 11a as it is and being emitted to the outside.

Since each of the inclined surfaces 11a has a predetermined convex curved surface, for example, as shown in FIG. 11, as compared with a case where the two inclined surfaces 11b, 11b of the recessed portion 11A are made flat. It is possible to further increase the angle of incidence when the light emitted from the LED 3 enters each inclined surface. Therefore, the first light exit surface 1 of the first light guide member 1
This is advantageous in preventing the light from being intensively emitted to the outside from the substantially central portion in the longitudinal direction of No. 2. In the configuration shown in FIG. 11, two inclined surfaces 11b, 11b and a first side surface 1 are provided.
0A intersect each other in a relatively sharp edge shape, and the first light guide member 1
Although light leaks easily to the outside of the first embodiment, the first
In the light guide member 1, such an inconvenience hardly occurs because the upper part of each inclined surface 11a has a smooth curved surface shape. However, in the present invention, as shown in FIG.
The first light guide member 1 may have a configuration in which a concave portion 11A having planar inclined surfaces 11b, 11b is formed.

In FIG. 10, most of the light that has entered the first light guide member 1 from the first light incident portion 15 is totally reflected by the inclined surfaces 11a, 11a, and the first light guide member 1 is eventually reflected. In the longitudinal direction. Then, the first side surface 10A, the second side surface 10B, the third side surface 10C, and the fourth
While repeating total reflection at various points on the side surface 10D, the first light guide member 1 reaches both ends in the longitudinal direction. Second side 1
When light is incident on 0B, the light is totally reflected in each plane portion 13. On the other hand, most of the light incident on the inclined surface 14a of the concave portion 14 is reflected in a form close to scattered reflection, and the course of the light is rapidly changed. And
The possibility of incidence on the first side face 10A at an incident angle smaller than the critical angle for total reflection is increased. For this reason, most of the light reflected by the inclined surface 14a and traveling in the direction of the first side surface 10A passes through the first side surface 10A and exits outside the first light guide member 1. Therefore, the first
Despite the provision of the light incident portion 15 at the central portion in the longitudinal direction of the first light guide member 1, light can be emitted almost uniformly from the entire length region of the first light exit surface 12 in the longitudinal direction. .

However, in the present invention, the second aspect 10
B instead of the means for providing the concave portion 14 in the second side 1
A means for forming a concave portion of another shape having an inclined surface such as a triangular cross section at 0B, a means for making the surface of the second side surface 10B a rough surface with minute unevenness, and a steep light path on the second side surface 10B. Means for providing a plurality of protrusions that can be changed at appropriate intervals, or means for applying a paint of white or another color that scatters and reflects light to the surface of the second side surface 10B may be employed. Even by such means, when light traveling inside the first light guide member 1 reaches the second side surface 10B, part of the light is reflected in the direction of the first side surface 10A, and the first side surface 10A At a small angle of incidence.

FIG. 12 is a partially sectional perspective view showing the second light guide member 2.

The second light guide member 2 comprises a second transparent member 2
0 occupies the main part and is formed, for example, by cutting a transparent plate glass. A method for manufacturing the second light guide member 2 from sheet glass will be described later. The second light guide member 2 has an overall length substantially equal to that of the first light guide member 1, and has a first side surface 20 extending in a certain direction.
A, a second side surface 20B, a third side surface 20C, and a fourth side surface 20D. The first side surface 20A and the second side surface 20B are opposed in the thickness direction of the second light guide member 2 and are substantially parallel. The first side surface 20A is provided with a step portion 29, and the first side surface 20A is divided into two step surfaces 27a and 27b. As will be described later, of the two step surfaces 27a and 27b, one of the step surfaces 27a on the higher step surface side is the second light emitting surface 25 in the present invention, and is also the image reading surface. On the other hand, the third side surface 20C and the fourth side surface 20D face each other in the width direction of the second light guide member 2.

As shown in FIGS. 2 and 3, the second light guide member 2 is disposed above the first light guide member 1, and a part of the second side surface 20B is partially covered with the first light guide member. The first light emitting surface 12 is provided so as to face the first light emitting surface 12. The first light emitting surface 1
The portion facing 2 is the second light incident portion 25. The third above
The side surface 20C is inclined so as to face the second light incident portion 25, and the light incident from the second light incident portion 25 to the inside of the second light guide member 2 is directed toward the fourth side surface 20D. It is a light reflecting surface that reflects light. The fourth side surface 20D is inclined so as to face the first side surface 20A, and
The light reflected from the side surface 20C is applied to the first side surface 20A.
This is a light reflecting surface that reflects light toward an area defined as the second light emitting surface 22. In the second side surface 20 </ b> B, a region below the second light emitting surface 22 reflects light emitted from the second light emitting surface 22 to a desired image reading target and reflected by the second light guide member 2. An image light emission surface 23 for emitting light downward and outward is provided.

Each outer surface of the second light guide member 2 is a mirror-like flat surface. Third side surface 20C and fourth side surface 20
If D is a mirror-like flat surface, light can be totally reflected by these surfaces, and light can efficiently travel in a predetermined course direction inside the second light guide member 2. is there.

The first light guide member 1 and the second light guide member 2
Is housed and arranged inside the case 4. The first light guide member 1 is arranged on one side of a space in which the lens array 51 and the light receiving element 52 are arranged, and the first light incident portion 15 has the LEDs 3 (3A to 3A) mounted on the circuit board 6.
It faces downward so as to face C). On the other hand, in the second light guide member 2, the second light incident portion 25 has the first light guide member 2.
The second light emitting surface 22 is disposed opposite to the light emitting surface 12.
Are substantially flush with the outer surface 4a of one side (upper surface) of the case 4. The image light emitting surface 23 is located immediately above the lens array 51 and the light receiving element 52.

FIGS. 13A and 13B show a developed state of the first light reflecting plate 8A. FIG. 13A is a plan view, and FIG.
It is X6-X6 sectional drawing of the same figure (a). FIG. 14 is a perspective view showing a state in which the first light reflecting plate 8A is assembled in a three-dimensional shape.

The first light reflecting plate 8A is for preventing the light passing through the inside of the first light guide member 1 and the second light guide member 2 from being unduly leaked. This first light reflection plate 8
A has a white surface so as to increase the light reflection efficiency. Further, the first light reflection plate 8A is provided in the above-described FIG.
And a thin synthetic resin sheet 80 cut into a predetermined shape as shown in FIG. The longitudinal dimension of the sheet member 80 is substantially the same as the longitudinal dimension of the first light guide member 1 and the second light guide member 2, and a plurality of bent portions for assembling the sheet member 80 three-dimensionally. Line N
Is provided. When it is difficult to bend the folding line N, for example, because the sheet body 80 is relatively hard, the bending work is improved, and the first light guide member 1 and the second light guide member are used. In order to improve the adhesion to the outer surface of No. 2, a part thereof is perforated line N (N
1) or a cut line N (N2).

The first light reflecting plate 8A is formed by bending the sheet member 80 along each of the plurality of bending lines N, as shown in FIG. The member 2 is formed in a shape capable of covering a predetermined outer surface. More specifically, the first light reflecting plate 8A is
The other side surface 10 of the first light guide member 1 except for the first light exit surface 12
Regions 80b corresponding to B, 10C, and 10D,
80c, 80d, and the second light guide member 2
And a region 80f corresponding to a portion of the second side surface 20B of the second light guide member 2 other than the second light incident portion 25 and the image light emitting surface 23. .

At a predetermined position of the first light reflection plate 8A, an opening 81, a through hole 82, and a plurality of other through holes 83 are provided. The opening 81 is formed by the first
This is for avoiding interference between the light reflection plate 8A and the LED 3. The through hole 82 is provided with a first fixing member 7A described later.
The light-shielding plate portion 72 is inserted therethrough. The plurality of through holes 83 are portions through which the protrusions 71 of the second fixing member 7B are inserted.

At both ends in the longitudinal direction of the first light reflecting plate 8A, side pieces 80a, 80a are provided. By folding the side pieces 80a, 80a, respectively, as shown in FIG. The end face 10F of the first light guide member 1 (10
E). The end face 10F of the first light guide member 1 is formed by the side pieces 80a, 80a.
If (10E) is covered, it is possible to surely reflect the light that has traveled to both longitudinal end portions of the first light guide member 1 and reached the end surface to the inside of the first light guide member 1, and light loss Can be reduced. The side pieces 80a, 80
a is fixed by being sandwiched between an end face 10F (10E) of the first light guide member 1 and an inner wall portion of the case 4 facing the end face 10F (10E).
E). When the first light guide member 1 is accommodated in the case 4, the second side surface 10B of the light guide member 1 and the upper surface portion 44 at the bottom of the case 4 are located in the region 80b of the first light reflection plate 8A. The fixing is achieved by being sandwiched in between.

In FIGS. 2 to 5, the second light reflecting plate 8B is formed by a white sheet member similar to the first light reflecting plate 8A. This is a member for preventing light from leaking by reflecting light transmitted through the side surface 20D. Therefore,
The shape and size are substantially the same as the fourth side surface 20D. The second light reflecting plate 8B is connected to the fourth side surface 20.
D and the inner wall surface of the case 4 facing the fourth side surface 20D, and is in close contact with the fourth side surface 20D. Thus, the second light reflecting plate 8B is
If it is sandwiched between the light guide member 2 and the case 4,
The inconvenience of adhering the second light reflection plate 8B to the case 4 using, for example, an adhesive or the like can be eliminated, and the assembling work can be facilitated. This is the same for the side piece 80a described above.

FIG. 15 shows the first fixing member 7A.
(A) is the front view, (b) is X7 of (a)
-It is X7 cross section. (C) is an X8-X8 sectional view of (a).

The first fixing member 7A is made of, for example, an acrylic synthetic resin such as PMMA of the same material as the first light guide member 1. However, the overall color is white with high light reflection efficiency. This first fixing member 7A
Is a fixed member main body 70A formed to have substantially the same overall length as the first light guide member 1 and the second light guide member 2, and a protruding piece provided in series along the upper edge of the fixed member main body 70A. 75,
Further, a plurality of light shielding plate portions 72 provided at a substantially central portion in the longitudinal direction of the fixing member main body 70A are provided.

The fixing member main body 70A includes a fourth side surface 10D of the first light guide member 1 and a third side surface 20C of the second light guide member 2.
Has one side surface 73A corresponding to the cross section. Therefore, by disposing the first fixing member 7A outside the first light guide member 1 and the second light guide member 2, as shown in FIGS. 2 and 3, the second light reflection plate 8A
Is pressed by the first fixing member 7A, and the fourth side surface 10D of the first light guide member 1 and the second light guide member 2 are pressed.
And the third side surface 20C. Also,
The protruding piece 75 is in face-to-face contact with the step surface 27b of the second light guide member 2. The thickness of the protrusion 75 is substantially the same as the step of the step 29, and the upper surface of the protrusion 75 and the second
The light emission 22 is set substantially flush.

The fixed member main body 70A comprises a first light guide member 1 and a second light guide member 2 covered by a first light reflection plate 8A.
Are formed in a shape and a size that can be fitted into the space S1 on one side of the first light reflection plate 8A that can be generated when the first light reflection plate 8A is accommodated in the case 4. Therefore, in a state where the first fixing member 7A is disposed at a predetermined position in the case 4, the first light guide member 1 and the second light guide member 2 are loosely formed on one side of the first light reflection plate 8A. Can be filled by the first fixing member 7A.

The plurality of light shielding plate portions 72 are provided in a stripe shape with an appropriate gap formed between them. The plurality of light shielding plate portions 72 are inserted through the through holes 82 of the first light reflection plate 8A. As is apparent from FIG. 1, a part of both ends of the plurality of light shielding plate portions 72 is
The first light guide member 1 and the second light guide member 2 are interposed between the first light guide member 1 and the second light guide member 2, so that the first light exit surface 12 and the second light incident portion 25 are prevented from coming into face-to-face contact with each other over a wide area. I have. That is, an air layer serving as the gap Sa is formed between the first light exit surface 12 and the second light entrance 25. Since the first light emitting surface 12 and the second light incident portion 25 are in close contact with each other, light traveling in the longitudinal direction in the first light guide member 1 is incident on the first light emitting surface 12. In addition, regardless of the incident angle, there is a possibility that the light may proceed into the second light guide member 2 as it is. However, if the air layer is formed as described above, The light incident at an angle larger than the predetermined critical angle for total reflection can be totally reflected to the inside of the first light guide member 1 by the first light emitting surface 12 without fail.

On the other hand, a part of the intermediate portion among the plurality of light shielding plate portions 72 faces the concave portion 11 of the first light guide member 1. The surface of the light-shielding plate 72 is in contact with the first light guide member 1.
When receiving the light emitted from the region of the concave portion 11, the white surface is scattered and reflected at a high reflectance.

FIG. 16 shows the second fixing member 7B,
FIG. 1A is a front view. FIG. 2B is a cross-sectional view taken along the line X9-X9 in FIG.

The second fixing member 7B is made of, for example, the same material as the first fixing member 7A, and has an overall color of white having high light reflection efficiency. The second fixing member 7B is provided on one side surface 73B of the fixing member main body 70B which is formed in a substantially plate shape having substantially the same overall length as the entire length in the longitudinal direction of the first light guide member 1 and the second light guide member 2. A plurality of projections 71 are provided at appropriate intervals in the longitudinal direction.

As shown in FIG. 3, the second fixing member 7B allows each of the projections 71 to be inserted into each of the through holes 83 of the first light reflecting plate 8A, and the distal end thereof to be inserted. The first light-guiding member 1 is attached to the first light-guiding member 1 by further fitting into the holes 18.
By attaching the second fixing member 7B, the first light reflecting plate 8
A predetermined region is a side surface portion 73B of the fixing member main body 70B.
And is in close contact with the third side surface 10 </ b> C of the first light guide member 1. The fixing member main body 70B is provided with a first light reflecting plate 8A that can be generated when the first light guiding member 1 and the second light guiding member 2 covered by the first light reflecting plate 8A are accommodated in the case 4. It is formed in a shape and a size that can be fitted into the gap S2 on the other side. Therefore, when the second fixing member 7B is arranged at a predetermined position in the case 4, the first light guide member 1 and the second light guide member 2
The gap (gap S2) that causes backlash in the second
It can be filled by the fixing member 7B.

In FIG. 2 to FIG. 5, the lens array 51 is for converging light reflected from an object to be read, which is disposed opposite to the second light exit surface 22 of the second light guide member 2. is there. The light receiving elements 52 receive the light converged by the lens array 51 and perform photoelectric conversion of the light. The light receiving elements 52 are provided in a large number so as to extend in the longitudinal direction of the circuit board 6.

As the LED 3 (3A to 3C),
A total of three types of chip-shaped LEDs that emit light of each color of R, G, and B (red, green, and blue) are used.
The three types of LEDs 3 are mounted on the surface of the circuit board 6 so as to be located in the concave portions 16 of the first light guide member 1. The arrangement is, for example, the above-mentioned three types of LEs.
D3 are in a line in the width direction of the first light guide member 1. The arrangement order of the LEDs 3 is such that the LEDs 3B that emit G light whose emission amount is substantially the least
Is set in the middle of the other LEDs 3A and 3C.

The circuit board 6 is made of, for example, glass epoxy resin or ceramics, and has on its surface a conductive wiring pattern (not shown) for mounting the large number of light receiving elements 52 and a set of LEDs 3. Is provided.
Further, a connector terminal 61 is attached to an appropriate position of the circuit board 6. By wiring and connecting an external control device (not shown) to the connector terminal 61, the light receiving element 52 and the LED 3 can be connected to the external control device by wiring. Of course, the case 4 has a space (not shown) in which the connector terminal 61 can be attached.
Are provided as appropriate.

As is apparent from FIG. 3, the circuit board 6 is fitted into a concave portion 46 provided at the bottom of the case 4 from below the case 4. Each of the two attachments 69 is for attaching the circuit board 6 to the case 4.
The circuit board 6 is prevented from dropping downward by externally fitting from below and being hooked by engagement projections 48 provided on the left and right outer surfaces of the case 4. Each of the attachments 69 is formed by, for example, pressing a thin metal plate, and exhibits appropriate elasticity.

In the image reading apparatus A having the above configuration, as shown in FIG. 4, the first light guide member 1, the second light guide member 2, the first light reflecting plate 8A, the first fixing member 7A, and the second
Each component of the fixing member 7B can be assembled substantially integrally. That is, after a predetermined outer surface area of the first light guide member 1 and the second light guide member 2 is covered with the second light reflection plate 8A, the protrusion 71 of the second fixing member 7B is moved to the first light reflection plate 7A.
Are inserted into the recesses 18 of the first light guide member 1 and the plurality of light shielding plate portions 72 of the first fixing member 7A are inserted through the through holes 82, so that each of the above members can be inserted. It can be assembled almost integrally.

Therefore, at the time of assembling and manufacturing the image reading device A, it is sufficient to integrally insert predetermined components of the light source device into the case 4 as described above. Become. In this case, as shown in FIG. 4 described above, chamfers 76 a and 76 b are provided in advance at the lower end of the first fixing member 7 </ b> A or at a predetermined area on the inner surface of the case 4, so that the components are moved into the case 4. Insertion work can be performed smoothly.

When the components of the light source device are inserted into the case 4, the first fixing member 7A and the second fixing member 7B fill predetermined gaps S1 and S2 in the case 4. The first light guide member 1 and the second
The positioning and fixing of the light guide member 2 can be achieved. Therefore, even if the components are not necessarily fixed by using an adhesive or the like, the components of the light source device can be accurately positioned and held in the case 4, and the components can be connected to the LED 3, the lens array 51, and the light receiving device. It is possible to arrange them at appropriate positions in relation to the element 52 and the like.

Next, the operation when an image reading operation is performed using the image reading apparatus A will be described.

First, the second light emitting surface 22 of the second light guide member 2
A document G as an example of an object to be read is arranged to face upward. Next, when any one of the three types of LEDs 3 emits light, as described with reference to FIG. 10 above, the light incident from the first light incident portion 15 into the first light guide member 1 at an appropriate spread angle. Is emitted from various parts of the first light emitting surface 12 while repeating total reflection and traveling toward both ends in the longitudinal direction of the first light guide member 1. And
The light emitted from the first light emitting surface 12 is then incident on the inside of the second light guide member 2 from the second light incident part 25,
The light is guided to the second light emitting surface 22 by being reflected by the third side surfaces 20C and 20D, and is irradiated on the document G in a belt shape. Then, the light is reflected by the original document G, travels inside the second light guide member 2 and moves to the image light exit surface 23.
And is received by the light receiving element 52 through the lens array 51.

Therefore, it is possible to appropriately read the image of the document G, even though the second light emitting surface 22 of the second light guide member 2 is used as the image reading surface. Since the second light exit surface 22 is exposed to the outside of the case 4, there is a possibility that an image reading object or other articles may come into contact with or collide with this portion.
If the thickness of the light guide member 2 is made relatively large, it is possible to keep the strength sufficiently to withstand such a situation.
Apart from the second light guide member 2, it is not necessary to use a thick cover glass. Further, since the second light emitting surface 22 is substantially flush with the outer surface 4a on one side of the case 4, when the original G is transported along these surfaces, the original G
Can be prevented from being easily caught on the outer surface of the case.

In the image reading apparatus A, the LE
When the light emitted from D3 travels inside the first light guide member 1, each side surface 10A to 10A to 10C of the first light guide member 1
When light is incident on D at an angle smaller than a predetermined total reflection critical angle, the light is transmitted to the outside of the first light guide member 1 as it is. However, the side surfaces 10 </ b> B to 10 </ b> B of the first light guide member 1 other than the first light emission surface 12.
10D and the end faces 10E and 10F are connected to the first light reflecting plate 8
Because of being covered by A, such transmission of light is properly prevented. Therefore, the first light guide member 1 efficiently guides light to the entire length region in the longitudinal direction.

Similarly, since a part of the outer surface of the second light guide member 2 is also covered by the first light reflecting plate 8A, most of the light incident on the inside of the second light guide member 2 is also removed. Unreasonable leakage to other parts in the case 4 is also suppressed. Therefore, the first light exit surface 1 of the first light guide member 1
Most of the light emitted from the light source 2 is efficiently guided to the second light emission surface 22, and the illuminance of the irradiation surface of the document G can be increased. Since the first fixing member 7A and the second fixing member 7B located outside the first light reflecting plate 7A are of a white color that does not easily transmit light, the first fixing member 8A and the second fixing member 7B may
Even if a situation where light is transmitted through A occurs, the light can be reflected by the first fixing member 7A and the second fixing member 7B into the first light guide member 1 and the second light guide member 2. It is possible to more thoroughly prevent light leakage.

On the other hand, the first light guide member 1 causes the light emitted from the LED 3 to travel in the longitudinal direction.
The amount of light emitted from the area of the concave portion 11 is smaller than that of the first light emitting surface 12.
Tend to be larger than the amount of light emitted from other regions. This is because the concave portion 11 is the region closest to the LED 3. However, most of the light emitted from the concave portion 11 is shielded and scattered and reflected by the light-shielding plate portion 72 located above the concave portion 11, so that a portion of the second light incident portion 25 facing the concave portion 11. Therefore, the amount of light incident on the second light guide member 2 from the second light guide member 2 can be reduced. Therefore, it is possible to suppress the light from being intensively incident on the specific portion of the second light incident portion 25, and to appropriately achieve the uniform light amount distribution in the longitudinal direction of the reading line on the image reading surface. Since a plurality of the light shielding plate portions 72 are provided at appropriate intervals, the uniformity of the light amount distribution can be set to an optimum state by changing the interval size and the number thereof.

In the image reading apparatus A, the second
The first light exit surface is provided to guide the light incident into the light guide member 2 to the second light exit surface 22 after being reflected by the third side surface 20C and the fourth side surface 20D located at a predetermined distance from each other. It is possible to make the optical distance from 12 to the image reading surface 28 correspondingly longer. If the optical distance is increased, the variation in the amount of light in the longitudinal direction of the first light emitting surface 12 can be reduced along the optical path. Therefore, even in such a case, it is possible to reduce the variation in the illuminance in the longitudinal direction of the reading line on the image reading surface.

FIGS. 17 to 20 are cross-sectional views of a main part of an example of a method of manufacturing the light guide member applied to manufacture the second light guide member 2. As shown in FIGS.

As shown in FIG. 17, this manufacturing method uses two parallel flat portions 95 as a raw material of the second light guide member 2.
A glass plate 95 having a constant thickness 95a and 95b is used.
The width dimension of the plate glass 95 is a dimension that allows a large number of second light guide members 2 to be obtained, and is considerably wider than one second light guide member 2. From the above-mentioned plate glass 95 to the second light guide member 2
In order to manufacture the plate glass 95, the plate glass 95 is first cut at a predetermined pitch interval using a first cutting blade 89A as shown in FIGS. This pitch interval is, for example, equal to the width of two second light guide members 2. The first cutting blade 89A is configured as, for example, a disk-shaped grindstone that can be driven and rotated, and has an inclined surface having the same cross-sectional shape as the third side surface 20C of the second light guide member 2 on both surfaces of its outer peripheral edge. The planar blades 88a, 88a are formed symmetrically to the left and right. Preferably, the blade 88
a, 88a are also provided with shoulders 87, 87 for forming the step surface 27b of the second light guide member 2.

According to the cutting operation using the first cutting blade 89A, each of the side surfaces 95c, 95c as the cut end surfaces on both sides of the cut portion is connected to the third side surface 20C of the second light guide member 2. Has the same cross-sectional shape. Further, the cutting member 9 of the sheet glass 95 obtained by the above-described cutting operation is used.
5A has side portions 95c, 95 having the same cross-sectional shape as the third side surface 20C of the second light guide member 2 at both ends in the width direction.
c is formed.

Next, after the cutting member 95A is obtained, as shown in FIG. 20, the cutting member 95A is turned upside down, and then the cutting member 95A is turned using a second cutting blade 89B. It is cut at the center in the width direction. The second cutting blade 89B is provided with the first cutting blade 89B.
Is configured as, for example, a disc-shaped grindstone, like the cutting blade 89A of
Blade portions 88b, 88b having the same cross-sectional shape as the fourth side surface 20D of the second light guide member 2 are formed symmetrically to the left and right. According to the cutting operation using the second cutting blade 89A, the cutting member 95A is divided into two cutting members 95B.
Each of the side portions 95d, 95d, which are cut end surfaces on both sides of the cut portion, has a cross-sectional shape similar to that of the fourth side surface 20D of the second light guide member 2. As a result, the cutting member 95B is moved to both side surfaces 9 in the width direction.
Each of 5c and 95d has the same cross-sectional shape as the third side surface 20C and the fourth side surface 20D of the second light guide member 2, and is a member in which the flat portions 95a and 95b face each other in the thickness direction.
The second light guide member 2 is manufactured. Of course,
A predetermined step surface 27b can be formed on this member by the cutting step of the first cutting blade 89A.

As described above, in the above manufacturing method, a large number of second light guide members 2 can be obtained simply by cutting the plate glass 95 using the two cutting blades 89A and 89B. Therefore, the manufacturing cost can be reduced.
Although the surface of the cut surface by the cutting blades 89A and 89B tends to be a rough surface having fine irregularities, as described above, the third side surface 20C, the fourth side surface 20D, and the fourth side surface 20D of the second light guide member 2 are provided. Even if the step surface 27b is a rough surface, there is no inconvenience, and the member manufactured by the above method can be used as it is as the second light guide member for the image reading device. If the cut surface is subjected to heat treatment or chemical treatment, the surface can be formed into a smooth surface. The member subjected to such treatment is used as a second light guide member for an image reading device. May be used.

The second light guide member used in the present invention may be manufactured by a manufacturing method other than the above-described manufacturing method. For example, the second light guide member may be formed in the same manner as the first light guide member. It may be made of a synthetic resin of a suitable material, and may be resin-molded. In addition, the first light guide member has a first light guide member.
The side surface may not be provided with the step portion 29 or the step surface 27a.

Further, the specific configuration of each part of the image reading apparatus according to the present invention is not limited to the above embodiment, but can be variously changed in design. In the above embodiment, a part of the first side surface 20A of the second light guide member 2 is used as the second light emission surface. However, the present invention is not limited to this. The entire surface area of the side surface may be the second light emission surface. In the invention of the present application, the first light guide member has a function of dispersing light incident from the light source to the inside in a strip shape and emitting the light from substantially the entire length region of the first light emission surface having a certain length. For example, the light guide member described in FIGS. 21 and 22 as the prior art of the present application may be used as the first light guide member. Further, when the image reading apparatus is adapted for reading a so-called monochrome image which does not correspond to reading a color image, it is not always necessary to use a light source combining a total of three colors of R, G and B, but a light source of a single color. Is fine. However, in this case, it is preferable to use a white light source.
The image reading device according to the present invention includes various types of a type in which a platen roller is pressed against a second light c surface of a second light guide member serving as an image reading surface, a handy scanner type in which the platen roller is not in contact, or other types. Can be configured as an image reading device.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part showing an example of an image reading apparatus according to the present invention.

FIG. 2 is a sectional view taken along line X1-X1 of FIG.

FIG. 3 is a sectional view taken along line X2-X2 of FIG.

FIG. 4 is a sectional view showing a state where the image reading apparatus shown in FIG. 1 is assembled.

FIG. 5 is an exploded perspective view of the image reading device shown in FIG.

FIG. 6 is a front view illustrating an example of a first light guide member.

FIG. 7 is a plan view illustrating an example of a first light guide member.

8 is a sectional view taken along line X3-X3 of FIG.

FIG. 9 is a sectional view taken along line X4-X4 of FIG. 6;

FIG. 10 is an explanatory diagram showing an operation of the first light guide member.

FIG. 11 is an explanatory view of a main part showing another example of the first light guide member.

FIG. 12 is a partially sectional perspective view showing an example of a second light guide member.

FIG. 13 shows an example of a deployed state of the first light reflecting plate,
(A) is a plan view, (b) is X6 of the same figure (a)
It is -X6 sectional view.

FIG. 14 is a perspective view showing a state where the first light reflecting plate shown in FIG. 13 is assembled in a three-dimensional manner.

15A and 15B show an example of a first fixing member, wherein FIG. 15A is a front view, FIG. 15B is a cross-sectional view taken along the line X7-X7 of FIG. 9) is a sectional view taken along line X8-X8.

16A and 16B show an example of a second fixing member, wherein FIG. 16A is a front view, and FIG. 16B is a sectional view taken along line X9-X9 of FIG.

FIG. 17 is a fragmentary cross-sectional view showing an example of the method for manufacturing the light guide member according to the present invention.

FIG. 18 is a fragmentary cross-sectional view showing an example of the method for manufacturing the light guide member according to the present invention.

FIG. 19 is a fragmentary cross-sectional view showing an example of the method for manufacturing the light guide member according to the present invention.

FIG. 20 is a fragmentary cross-sectional view showing an example of the method for manufacturing the light guide member according to the present invention.

FIG. 21 is an explanatory diagram illustrating an example of a conventional image reading apparatus.

22A is an explanatory diagram of a linear light source device used in the image reading device shown in FIG. 21; FIG.
FIG. 4 is an explanatory diagram showing a relationship between a relative position of the linear light source device and illuminance.

[Explanation of symbols]

 A image reading device 1 first light guide member 2 second light guide member 3 LED (light source) 4 case 4a outer surface (of the case) 6 circuit board 7A first fixing member 7B second fixing member 8A first light reflecting plate (light) 8B 2nd light reflector 10A 1st side (of 1st light guide member) 10B 2nd side (of 1st light guide member) 10C 3rd side (of 1st light guide member) 10D 4th side ( 1st light guide member) 12 1st light emission surface 15 1st light incidence part 20A 1st side surface (of 2nd light guide member) 20B 2nd side surface (of 2nd light guide member) 20C 3rd side surface (2nd) 20D Fourth side surface (of the second light guide member) 22 Second light exit surface 23 Image light exit surface 25 Second light incident portion 27b Step surface 29 Step portion 51 Lens array 52 Light receiving element 75 Projection piece (Of the first fixing member) 89A first cutting blade 89B 2 blades for cutting G manuscript (image reading object)

Claims (11)

[Claims] 1. A light source, a first light guide member for dispersing light incident inside from the light source into a band shape and emitting the light from a substantially entire length of a first light emission surface having a constant length, and an image reading member. A light receiving element, wherein a second light emission having a constant length by causing light incident from the first light emission surface of the first light guide member to travel through a predetermined path. An image reading unit that includes a second light guide member made of a transparent member that can emit light from substantially the entire length of the surface, and the second light emission surface of the second light guide member reads an image by the light receiving element. An image reading apparatus, wherein the image reading surface is an image reading surface for causing an object to face and contact. 2. The second light guide member has a plurality of outer peripheral side surfaces extending in a longitudinal direction of the second light guide member, and the whole or a part of the first side surface of the plurality of outer peripheral side surfaces. Region is the second light exit surface, and a partial region of the second side surface facing the first side surface in the thickness direction is:
An image light emission surface for emitting light, which is emitted from the second light emission surface to a desired object to be read and reflected inside the second light guide member, to the outside of the second light guide member. The image reading device according to claim 1, wherein the light receiving element is provided so as to be able to receive light emitted from the image light emission surface. 3. The light guide member according to claim 1, wherein the second light guide member has a region other than the image light exit surface or a part of the second side surface that transmits light from the first light guide member into the second light guide member. A third side surface and a fourth side surface of the plurality of outer peripheral side surfaces facing the width direction of the second light guide member are formed from the light incident portion. The image reading device according to claim 2, wherein the image reading device has an inclined light reflecting surface that sequentially reflects the light incident into the optical member so as to guide the light to the second light emitting surface. 4. The second light guide member is made of glass.
The image reading device according to claim 1. 5. The image reading device according to claim 1, wherein the second light guide member is made of a synthetic resin. 6. A light source, a first light guide member, a second light guide member, and a case capable of accommodating a light receiving element therein, and an outer surface of one side of the case and the second light guide member. 6. The second light exit surface of claim 1 is substantially flush with the second light exit surface.
The image reading device according to any one of the above. 7. A case capable of accommodating the light source, the first light guide member, the second light guide member, and the light receiving element, and the first light guide member and the second light guide member in the case. The first light guide member and the second light guide member are fitted into gaps formed outside of the first light guide member and the second light guide member in the case so that the first light guide member and the second light guide member are positioned and held when housed. The image reading device according to claim 1, further comprising one or more fixing members that can be combined. 8. A part of the outer peripheral side surface of the second light guide member, on which the second light emitting surface is formed, has a part of the first side surface more than the second light emitting surface. A step portion as a concave step surface is provided, and the fixing member,
The image reading device according to claim 7, further comprising a protruding portion that comes into contact with the step surface so as to prevent the second light guide member from being removed when the second light guide member is housed in the case. 9. The image according to claim 7, wherein a light reflecting member is interposed between the outer surface of each of the first light guiding member and the second light guiding member and the fixing member. Reader. 10. A light guide member comprising a transparent member having a plurality of planar outer peripheral side surfaces extending in a predetermined direction, wherein the plurality of outer peripheral side surfaces is a first side surface opposed to a thickness direction of the light guide member. And a second side surface, and a third side surface and a fourth side surface facing each other in the width direction of the light guide member. The third side surface is inclined so as to face a partial area of the second side surface. Wherein the fourth side surface is an inclined surface that is inclined so as to face a partial area of the first side surface. 11. A method for manufacturing a light guide member for manufacturing the light guide member according to claim 10 from sheet glass, wherein the light guide member has one of a third side surface and a fourth side surface. Using a first cutting blade having blades of corresponding shapes on both sides, sequentially cutting a sheet glass wider than the light guide member at a predetermined pitch; and a third side and a fourth side of the light guide member. A step of further cutting a widthwise intermediate portion of the plate glass cut by the first cutting blade using a second cutting blade having a blade portion having a shape corresponding to the other cross-sectional shape of the side surface on both surfaces; A method for manufacturing a light guide member, comprising: