JPH11215302A - Image reader and resin package type light source - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the manufacturing cost of the image reader by simplifying a light source assembling structure to facilitate its assembling job when the reader is configured such that a light guide body emits a light from a light source to a linear area. SOLUTION: This resin package type light source 5 is used for a light source, where a light source main body is packaged by a packaging resin 52 forming a light transmission window 54 to a front part 52a and an electrode 53 is provided at the outside the packaging resin 52. The resin package type light source 5 is mounted on a printed circuit beard 3 so that the electrode 53 is in electrical continuity with a conduction wiring 30B provided for the printed circuit board 3 on which plural light-receiving elements 40 are mounted, and the light transmission window 54 is placed in an attitude facing a prescribed outer 10E of the light guide member 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image reading apparatus which is incorporated in a facsimile apparatus or various scanner apparatuses and is used for reading a document image.

[0002]

2. Description of the Related Art Conventionally, as this type of image reading apparatus, there is an image reading apparatus having a linear light source device B as shown in FIG. In this linear light source device B, light sources 91, 91 are opposed to end faces 90, 90 at both ends in the longitudinal direction of a light guide member 1e made of a transparent member having a fixed length. The light guide member 1e has a plurality of side surfaces extending in the longitudinal direction, and a second side surface 93 of the plurality of side surfaces facing the first side surface 92 in the thickness direction receives the received light. Is a light diffuse reflection surface that scatters and reflects light. Second
The other side surface except the side surface 93 has a smooth mirror surface.

In the linear light source device B, the light sources 91, 91
And emit the light from the end faces 90, 90 to the light guide member 1e.
When the light enters the inside, the light travels toward the center in the longitudinal direction while being totally reflected by the plurality of side surfaces extending in the longitudinal direction of the light guide member 1e. However, the light that has reached the second side surface 93 is scattered and reflected, and a part of the scattered and reflected light is emitted to the outside from substantially the entire length of the first side surface 92. That is, when light travels inside the light guide member 1e, when light enters the mirror-like side surface of the light guide member 1e at an angle larger than the critical angle for total reflection specified by the material of the light guide member 1e, The light is totally reflected, but when the incident angle of the light is smaller than the critical angle for total reflection, the light passes through the side surface of the light guide member 1e as it is. The scattered reflection of light by the second side surface 93 is such that light traveling inside the light guide member 1e is incident on the first side surface 92 at an incident angle smaller than the critical angle for total reflection, and The function of increasing the rate at which light is emitted to the outside is exhibited. By such an action, light is emitted from the substantially entire length region of the first side surface 92. Therefore, the first side surface 9
If the document 2 is opposed to the image reading area of the image reading apparatus, it is possible to irradiate light linearly on the surface of the document K arranged in that area. Further, in order to appropriately emit light from the substantially entire length region of the first side surface 92, it is necessary to cause light that has entered the light guide member 1e from the light sources 91, 91 to travel along the longitudinal direction of the light guide member 1e. The light guide member 1
If the light sources 91, 91 face the end faces 90, 90 of the longitudinal ends of e, the traveling direction of the light emitted from these light sources 91, 91 becomes the longitudinal direction of the light guide member 1e, which is convenient.

Conventionally, as means for providing a light source 91 beside the end face 90 of the light guide member 1e, for example, FIG.
The means as shown in FIG. That is, the means shown in the figure is composed of one or more LEDs mounted on the substrate 91b.
This means uses the lamp 91a as a light source.
The end surface 9 of the light guide member 1e with the ED lamp 91a turned sideways
In order to face the substrate 91, it is necessary to hold the substrate 91b in an upright state. On the other hand, the substrate 91b
Is simply a flat plate, and it is difficult to stand and hold it alone. Therefore, conventionally, the substrate 91b is supported by an appropriate portion of the housing of the image reading apparatus, or the substrate 91b is formed by using an appropriate member.
b was supported at the end of the light guide member 1e. Also, a plurality of wiring cords 91c electrically connected to the LED lamp 91a are soldered to the board 91b, and these wiring cords 91c are connected to a dedicated connector for connecting an external device, or a document image is connected. It was soldered to a circuit board (not shown) on which a light receiving element for reading was mounted.

[0005]

However, conventionally, when the substrate 91b is supported by the housing of the image reading apparatus, it is necessary to perform special processing on the housing. When the substrate 91b is supported by the light guide member 1e instead, a special component dedicated to the substrate 91b is required. Therefore, in any case, the substrate 91b
However, the structure for positioning and fixing is very complicated. Further, in any of the above cases, it is difficult to perform the mounting work of the board 91b by mechanical work,
Furthermore, it is difficult to solder a plurality of wiring cords 91c to a connector for connecting an external device or a circuit board on which a light-receiving element is mounted, and it is difficult to perform the work by assembling the light source by hand. did not become.
Therefore, conventionally, the workability of assembling the light source when manufacturing the image reading apparatus is poor, and the manufacturing cost of the image reading apparatus has been high.

The present invention has been devised in view of such circumstances, and when the light emitted from the light source is configured to be radiated to a linear region using a light guide member, An object of the present invention is to reduce the manufacturing cost of an image reading apparatus by simplifying an assembly structure of a light source and easily assembling the light source.

[0007]

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

[0008] According to a first aspect of the present invention, there is provided an image reading apparatus. The image reading device includes a plurality of light receiving elements that receive light reflected from the image reading target,
A circuit board on which the plurality of light receiving elements are arranged in a row; a light guide member having a plurality of side surfaces extending in the same direction as the row direction of the plurality of light receiving elements; A light source for projecting light on an outer surface portion having a width in the thickness direction, and light emitted from the light source and incident on the inside of the light guide member is in a longitudinal direction of the light guide member. An image reading device configured to emit to the outside of the light guide member from a fixed length region of a first side surface of the plurality of side surfaces of the light guide member while traveling, wherein the light source is: A light source main body is resin-packaged with a packaging resin forming a light-transmitting window on the front surface, and a resin package-type light source in which electrodes are provided outside the packaging resin. , Is mounted on the circuit board so as to be electrically connected to the conductive wiring portion provided on the circuit board, and the light-transmitting window portion is set in a posture facing the outer surface portion of the light guide member. Characterized.

The light source body may be one or a plurality of LED chips, and the resin package type light source may be a resin package type LED light source.
This resin package type light source may be configured to emit monochromatic light of white or other colors. Instead of this, the resin package type light sources are R, G, B
It is also possible to adopt a configuration that emits light of each color.

In the present invention, since the resin package type light source is mounted on the circuit board, unlike the prior art,
It is not necessary to perform special processing for positioning and fixing the light source on the housing of the image reading apparatus, or to separately prepare a reflector for supporting the light source on a light guide member or the like. In addition, since the resin package type light source is mounted so as to conduct to the conductive wiring portion provided on the circuit board, it is not necessary to connect a wiring cable for electric wiring to the resin package type light source. Further, since the circuit board on which the resin package type light source is mounted is a circuit board on which a light receiving element is mounted,
One circuit board is used for both the light receiving element and the light source to share parts, thereby also reducing the number of parts. As a result, according to the present invention, the structure for assembling the light source is significantly simpler than before. Further, a series of operations for mounting the resin package type light source on the circuit board can be performed by mechanical operations using, for example, a chip mounter. Therefore, the workability of assembling the light source can be improved, and the manufacturing cost of the image reading device can be reduced.

On the other hand, in the present invention, the resin package type light source is mounted on the circuit board on which the light receiving element is mounted, but the light transmitting window of the resin package type light source has a width in the vertical thickness direction of the light guide member. The light emitted from the resin package type light source can be appropriately projected on the outer surface of the light guide member, facing the outer surface. Therefore,
Light that has entered the light guide member from the outer surface portion can be emitted linearly from a fixed length region of the first side surface of the light guide member, and this light is transmitted to a linear image reading region. It is possible to irradiate appropriately.

As described above, according to the present invention, a resin package type light source is used as a light source, and the resin package type light source is received with its light-transmitting window facing the predetermined outer surface of the light guide member. It is based on a new technical concept of eliminating wiring cords and light source positioning and fixing means required for electrical connection of the light source by mounting on the element mounting board, and its utility value is enormous. .

In a preferred embodiment of the present invention, the electrode of the resin package type light source may be provided on a side surface of a packaging resin facing the circuit board.

According to such a configuration, when the resin package type light source is mounted on the circuit board, the electrodes of the resin package type light source can be directly opposed to the conductive wiring portions of the circuit board. The conductive connection with the unit can be reliably performed.

In another preferred embodiment of the present invention,
The electrode of the resin package type light source is provided on a back surface portion facing the front surface portion of the packaging resin, and is located near a side surface portion of the packaging resin facing the circuit board. Can be.

According to such a configuration, when the resin package type light source is mounted on the circuit board, the electrode provided on the back surface of the resin package type light source can be brought closer to the conductive wiring portion of the circuit board. Therefore, these electrodes and the conductive wiring portion can also be appropriately electrically connected by using, for example, solder.

In another preferred embodiment of the present invention,
A connector for external device connection is attached to the circuit board, and the connector has a conductive wiring portion that conducts to the plurality of light receiving elements and a conductive wiring portion that conducts to the electrode of the resin package type light source. Are connected together.

According to such a configuration, since the respective conductive wiring portions of the light receiving element and the resin package type light source are collectively connected to the common connector, the number of connectors can be minimized. Thus, the number of parts can be further reduced. Also, if you reduce the number of connectors,
The work of wiring and connecting the circuit board to the external device is also simplified and convenient.

In another preferred embodiment of the present invention,
The resin package type light source is provided so as to face an end face of one end in the longitudinal direction of the light guide member, and the light traveling from the one end to the end face of the other end in the longitudinal direction of the light guide member. May be provided with light reflecting means for reflecting the light toward the one end.

According to such a configuration, the number of the resin package type light sources can be minimized, and the manufacturing cost of the image reading apparatus can be further reduced. Further, when the light incident on the light guide member from the end face of the one end of the light guide member reaches the end face of the other end of the light guide member, the light is transmitted through the end face of the other end as it is to the outside. Leakage is also prevented, and light loss can be reduced.

In another preferred embodiment of the present invention,
The resin package type light source may be provided so as to be opposed to each end face of both ends in the longitudinal direction of the light guide member.

According to such a configuration, light can be made to enter the inside of the light guide member from a total of two end faces at both ends in the longitudinal direction of the light guide member. Therefore, only one end face of the light guide member is provided. Compared with the case where light is incident, the amount of light emitted from the first side surface can be easily increased.

In another preferred embodiment of the present invention,
The light guide member is disposed in the longitudinal direction such that an area of an end face of a longitudinal end portion where the resin package type light source is disposed to be opposed is larger than a cross-sectional area of a general portion of a longitudinal middle portion of the light guide member. The end may be configured to be thicker than the middle part in the longitudinal direction.

According to such a configuration, the light emitted from the resin package type light source can be made to efficiently enter the light guide member from the end face of the light guide member. That is, since the light emitted from the resin package type light source tends to travel radially with a certain spread angle, when the area of the end face of the light guide member is small, the amount of light applied to this end face decreases, Light incidence efficiency into the light guide member may be degraded. However, in the above configuration, the amount of light that passes through the end face and enters the light guide member can be increased by an amount corresponding to the increase in the area of the end face of the light guide member, thereby reducing light loss. be able to.

In another preferred embodiment of the present invention,
On the end face of the longitudinal end of the light guide member, a concave portion for housing and disposing the whole or a part of the resin package type light source is formed, and at the longitudinal end of the light guide member, A configuration in which a curved or planar inclined surface capable of reflecting light traveling from the resin package type light source in the lateral width direction or the vertical thickness direction of the light guide member toward the longitudinal middle portion of the light guide member is provided. It can be.

According to this configuration, the resin package type light source is accommodated in the concave portion formed on the end face of the light guide member, so that the light guide member is also provided around the resin package type light source. Is present. For this reason, even when light is emitted from the resin package type light source with a certain spread, much of the light can be made to enter the light guide member. Therefore, the efficiency of incidence from the light source into the light guide member can be increased. Also, of the light that has entered the light guide member, the light that has reached the inclined surface at the longitudinal end of the light guide member is reflected by the inclined surface toward the middle portion in the longitudinal direction of the light guide member. You can let it go. That is, when the light that has entered the inside of the light guide member reaches another side surface portion of the longitudinal end portion of the light guide member, the light may pass through the side surface portion and exit to the outside as it is. Can be reduced, and light can be prevented from being unnecessarily leaked outside from a region other than the first side surface of the light guide member. As a result, by appropriately propagating much of the light emitted from the light source into the light guide member, the amount of light emitted from the first side surface of the light guide member can be increased, and the illuminance of the image reading area can be increased. Can be.

According to a second aspect of the present invention, there is provided a resin package type light source. The resin package type light source includes a packaging resin in which one or a plurality of light source main bodies are resin-packaged, and an electrode that is electrically connected to the light source main body. The light source main body is provided on a front surface of the packaging resin. A resin package type light source provided with a light-transmitting window for irradiating light emitted from the outside to the outside, wherein the electrode has the package when the light-transmitting window is oriented in a substantially horizontal direction. It is provided on a side surface portion serving as a bottom surface of the sealing resin.

The resin-packaged light source provided by the second aspect of the present invention, when mounted on, for example, a horizontal substrate with the electrode provided on the side surface of the packaging resin facing downward, The light-transmitting window can be oriented substantially horizontally. Therefore, this resin package type light source can be suitably used as a light source for projecting light to the light guide member of the image reading device provided by the first aspect of the present invention.

The features and advantages of the present invention will become more apparent from the following description of embodiments.

[0030]

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 partially omitted sectional view showing an example of the image reading apparatus according to the present invention. FIG.
-It is a II sectional view. FIG. 3 is a sectional view taken along line III-III of FIG. FIG. 4 is an exploded perspective view of the image reading device shown in FIG.

The image reading apparatus A is configured as a contact type image sensor. As is clearly shown in FIG.
A circuit board 3; a plurality of sensor IC chips 4 mounted on the circuit board 3; a resin package type LED light source 5 (hereinafter abbreviated as “LED light source 5” in the present embodiment); a light guide member 1; Lens 6, first light reflecting member 7A, second
The light reflecting member 7B, the transparent plate 20, and one or more attachments 39 are provided. As described later, the sensor IC chip 4 has a plurality of light receiving elements 40 integrally formed.

The case 2 is made of, for example, a synthetic resin, and is formed in an elongated box shape having an opening at substantially the entire upper surface and an opening at the bottom as appropriate.
The main components of the image reading apparatus A described above are accommodated in the case 2. The transparent plate 20 serves as a document guide plate for arranging a document to be read in an opposed manner, and is made of, for example, glass or synthetic resin. The transparent plate 20 is attached to the case 2 so as to close the upper opening of the case 2, and a position immediately above the condenser lens 6 on the upper surface of the transparent plate 20 is an image reading area S. (See FIG. 2). The image reading area S is a linear area extending in the main scanning direction. For example, a platen roller 98 is disposed on the upper surface of the transparent plate 20, and the document K is transported in the sub-scanning direction by the platen roller 98.

FIG. 5 is a schematic perspective view, partially in section, showing the light guide member 1. FIG. 6 is a sectional view taken along line VI-VI of FIG.
FIG. 7 is an explanatory diagram illustrating the operation of the light guide member 1.

The light guide member 1 is provided for efficiently irradiating the light emitted from the LED light source 5 to the entire length of the linear image reading area S in the longitudinal direction. As best shown in FIG. 5, this light guide member 1 is, for example, PMMA
The transparent member 10 is obtained by molding an acrylic transparent resin such as the above, and the outer surface of each part is a mirror surface. If you make the surface of the transparent member a mirror surface,
In the case where light travels inside the transparent member, it is possible to totally reflect light rays incident on the surface of the transparent member at an angle larger than the total reflection critical angle 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 to the outside. The mirror surface is not necessarily required to be positively polished on the surface. For example, when a transparent member is resin-molded using a mold, it is a relatively smooth surface obtained by resin molding. Is also good.

The light guide member 1 can be divided into an auxiliary region Sb as one end in the longitudinal direction of the light guide member 1 and a main region Sa other than the auxiliary region Sb. The auxiliary area Sb
Converts the light emitted from the LED light source 5 into the main area Sa.
The main portion Sa is formed in an appropriate block shape, and the portion near the main region Sa does not cause a portion where the shape changes rapidly between the auxiliary region Sb and the main region Sa as much as possible. As described above, the shape gradually approaches the cross-sectional shape of the main region Sa. The auxiliary region Sb has an end face 10E having a width in the vertical thickness direction and the left and right width direction of the light guide member 1, and in the present embodiment, the end face 10E has a light incident surface that receives light from the LED light source 5. Has become.

The main area Sa has a uniform cross-sectional shape at various points in the longitudinal direction, and the first side face 10 extends in a certain direction.
A, second side 10B, third side 10C, fourth side 10
D, and an end face 10F at the other end in the longitudinal direction.
The first side face 10A and the second side face 10B face each other, and the third side face 10C and the fourth side face 10D face each other.

The first side surface 10A has a substantially full length region in the longitudinal direction serving as a light emitting surface for emitting light, and a central portion in the width direction bulges from a side edge in the width direction. Aspherical convex surface. The third side surface 10C
And the fourth side surface 10D, as well shown in FIG.
It is formed as a parabolic surface (quadratic surface) having the center axis C in the width direction between the third side surface 10C and the fourth side surface 10D as a common principal axis. The center line C is inclined with respect to the vertical direction. This is because the light emitted from the first side surface 10 is directly applied to the image reading area S as shown in FIG.

As shown in FIG. 7, the second side surface 10B is a surface passing through the common focal point O1 of the paraboloids of the third side surface 10C and the fourth side surface 10D or the vicinity thereof. Is formed. As shown in FIG. 6, a plurality of groove-shaped concave portions 14 are provided at appropriate intervals on the second side surface 10B. The region between the plurality of concave portions 14 is a mirror-like flat portion 13. The plurality of recesses 14 are portions that play a role of emitting light from the first side surface 10A by rapidly changing a traveling angle of light traveling in the light guide member 1, and have, for example, an arc-shaped cross section. . Other means for abruptly changing the traveling angle of light include means for providing a plurality of protrusions at appropriate intervals on the second side face 10B, and coating the second side face 10B with a material capable of scattering and reflecting light. Means to wear,
Means for forming the second side surface 10B into a rough surface with minute unevenness may be employed.

The light guide member 1 emits light that has entered the inside from the end face 10E from substantially the entire length of the first side face 10A. Specifically, as shown in FIG. 6, when light emitted laterally from the LED light source 5 at an appropriate spread angle enters the light guide member 1 from the end face 10E, the light travels into the main area Sa. I do. Then, the light repeatedly repeats total reflection at each of the first side surface 10A, the third side surface 10C, and the fourth side surface 10D, and at the plane portion 13 of the second side surface 10B, and the other end of the light guide member 1 in the longitudinal direction. To the end face 10F. When light is incident on the second side surface 10B, most of the light incident on each concave portion 14 is reflected in a form close to scattered reflection, and the course of the light is rapidly changed.
Therefore, most of the light reaching the second side surface 10B is
As shown in FIG. 7, the third side surface 10C and the fourth side surface 10C
D, and is totally reflected by the third side surface 10C and the fourth side surface 10D. However, since the third side surface 10C and the fourth side surface 10D are paraboloids, and the second side surface 10B is located near the focal point O1 of the paraboloid, the third side surface 10C and the fourth side surface 10D are parabolic. 4 sides 1
A large number of light rays reflected by the 0D travel toward the first side face 10A as a light ray bundle substantially parallel to the principal axis of the paraboloid, and go from various parts of the first side face 10A to the outside. Emit. At this time, the light beam is focused on the focal point O2 by the action of the convex surface of the first side surface 10A.

As shown in FIG. 2, the light guide member 1 is accommodated in the case 2 such that the first side face 10A faces the image reading area S. Therefore, the light emitted from the first side surface 10A does not disperse in various directions, efficiently irradiates the linear image reading area S, and irradiates the image reading area S with a substantially uniform position in the longitudinal direction. Is done.

The first light reflecting member 7A is a member that functions as a holder for the light guide member 1. More specifically, the first light reflecting member 7A has a groove 70 having a substantially V-shaped cross section with an open front surface, as best seen in FIGS. The member 1 is held by the first light reflecting member 7A by fitting the main area Sa into the groove 70. The light guide member 1 is disposed above the circuit board 3 by incorporating the first light reflection member 7A into the case 2. As the inner wall surface of the groove 70, the second side surface 1 of the light guide member 1 is used.
0B, the third side surface 10C, and the fourth side surface 10D, there are inner wall surfaces 70b, 70c, and 70d, respectively, which oppose each other.
It prevents leakage through B-10D to the outside. The first light reflecting member 7A is made of a white synthetic resin having a high light reflectance of about 97% or 98% on the surface thereof, for example.

Also, at one end in the longitudinal direction of the groove 70, a flat side face 70e facing the end face 10F of the light guide member 1 is provided, as is clearly shown in FIGS. . Therefore, when the light traveling inside the light guide member 1 reaches the end face 10F, the light is surely reflected by the side face part 70e, and the light is prevented from leaking to the outside from the end face 10F. You. The invention of the present application includes, as means for preventing light from leaking from the end face 10F of the light guide member 1 to the outside, the first type described above.
Instead of using the light reflecting member 7A, for example, a means of depositing a metal such as aluminum or chromium or other light reflecting material on the end face 10F may be adopted.

The second light reflecting member 7B includes the light guide member 1
And a member for preventing light from leaking out of the auxiliary region Sb. This second
The light reflecting member 7B of FIG.
As shown in FIG. 3 and well, it is externally fitted to the auxiliary area Sb and surrounds the outer surface of the auxiliary area Sb except for the end face 10E. The second light reflecting member 7B is also made of a white synthetic resin having a high light reflectance similarly to the first light reflecting member 7A.

The condenser lens 6 irradiates the image reading area S from the first side surface 10A of the light guide member 1 and focuses the light reflected by the original K on the transparent plate 20 onto a plurality of light receiving elements 40. It is intended to be. As the condensing lens 6, for example, a lens array in which a number of Selfoc lenses capable of converging an original image at an erect equal magnification is arranged in the main scanning direction is applied. Of course, a lens array in which convex lenses are arranged in series may be used instead.

The plurality of sensor IC chips 4 are formed by integrally forming a plurality of light receiving elements 40 on one surface of a semiconductor chip, and the light collected by the condenser lens 6 is received by the light receiving elements 40. To perform the photoelectric conversion,
It outputs an image signal of an output level corresponding to the amount of received light. The plurality of sensor IC chips 4 are
Are mounted in a row in the longitudinal direction.

FIG. 8 is a perspective view of the LED light source 5 as viewed from below. FIG. 9 is a sectional view of the LED light source 5. FIG. 10 is a schematic perspective view showing the internal structure of the LED light source 5. FIG. 11 is a cross-sectional view of a main part showing a structure of a mounting part of the LED light source 5.

The LED light source 5 is one in which three types of LED chips 50a to 50c respectively emitting R, G, and B light are packaged together in a resin, and is capable of reading a color image. More specifically, as shown in FIG.
Book first leads 51a and a total of three second leads 51b-
51d, and three types of LED chips 50a to 50d
50c is the first lead 51a formed relatively wide.
And is electrically connected to the first lead 51a. In addition, the above three types of LED chips 50a to 50a
c is connected to the second leads 51b to 51d via a wire W such as a gold wire. 4 leads 51a to 5 in total
Most parts of 1d are buried in the packaging resin 52, but some of them are exposed to the outside of the packaging resin 52 to be a total of four electrodes 53 for surface mounting. The electrodes of the first lead 51a are common electrodes, and the electrodes of the second leads 51b to 51d are individual electrodes. By supplying a drive voltage to these individual electrodes or connecting them to ground, three types of LED chips are provided. 50a-50
c can be individually driven for lighting.

The packaging resin 52 is formed in the shape of a rectangular parallelepiped, and the front surface 52a is provided with a concave light-transmitting window 54 so that the LED chip 50 is formed.
The light emitted from a to 50c passes through the light transmitting window 54 and is radiated to the outside. The light transmitting window 54 is filled with a transparent resin 55 such as an epoxy resin to protect the LED chips 50a to 50c and the like. As shown in FIG. 8, each of the four electrodes 53 can be disposed at the bottom surface of the packaging resin 52 when the light-transmitting window 54 is oriented substantially horizontally. Any one of the side portions 52
b.

The LED light source 5 is mounted on the surface (upper surface) of the circuit board 3 on which the plurality of light receiving elements 40 are mounted, as is clearly shown in FIG. More specifically, the LED light source 5 is mounted on the circuit board 3 in a state where the light-transmitting window portion 54 is oriented substantially in the horizontal direction and the side surface portion 52b is set to the bottom surface. The light window 54 is close to and opposed to the end face 10E so that light can be projected on the end face 10E of the light guide member 1. The plurality of electrodes 53 on the side surface portion 52b are opposed to the plurality of terminal portions 31 on the surface of the circuit board 3, and the plurality of electrodes 53 and the terminal portions 31 are joined to each other via a solder 89 to conduct electricity. ing.

FIG. 12 is an exploded perspective view of a main part of the image reading apparatus A.

As shown in the figure, the circuit board 3 has, on its surface, a first conductive wiring portion 30A conducting to the plurality of sensor IC chips 4, and a second conductive wiring portion conducting to the LED light source 5. 30B is formed by patterning with a copper foil or the like. The second conductive wiring portion 30B is an LED.
The plurality of terminal portions 31 for mounting the light source 5 are formed. A connector 32 for connecting an external device is attached to the circuit board 3.
The two types of conductive wiring portions 30A and 30B are collectively connected.

The circuit board 3 is mounted on the bottom of the case 2. The attachment 39 is for attaching and holding the circuit board 3 to the case 2. The attachment 39 is externally fitted to the case 2 from below, and the engagement protrusions 28 provided on the left and right side surfaces of the case 2 are provided. By being hooked on 28, the circuit board 3 is prevented from falling down. The attachment 39 is formed by, for example, pressing a thin metal plate.
It demonstrates moderate resilience.

Next, the operation of the image reading apparatus A will be described.

First, in the image reading apparatus A, since the LED light source 5 is directly mounted on the circuit board 3 on which a plurality of sensor IC chips 4 are mounted, the LED light source 5
A dedicated circuit board for mounting is not required, and L
A dedicated member for supporting the ED light source 5 is not required. Further, since the LED light source 5 is directly conducted to the terminal portion 31 of the circuit board 3, there is no need to use a wiring cord or the like to supply power to the LED light source 5, and the overall structure is very simple. Become.

The operation of mounting the LED light source 5 on the circuit board 3 is performed, for example, by applying cream solder on the terminal portion 31 of the circuit board 3 and then using a chip mounter to apply the LED light source 5 to the solder-coated portion. It can be carried out by putting it on the top, and then carrying the circuit board 3 into a reflow furnace and heating it. These series of surface mounting operations can be performed by a mechanical operation without requiring any manpower, and the workability can be made very good. As a result, the manufacturing cost of the image reading device A can be considerably reduced.

Further, the conductive wiring portions 30A and 30B of the sensor IC chip 4 and the LED light source 5 are connected to the common circuit board 3
The two types of conductive wiring portions 30
A and 30B can be created at the same time. Also,
One connector 32 is connected to two types of conductive wiring portions 30A and 30A.
B, the total number of connectors can be reduced, and the wiring connection for extracting the image signal from the sensor IC chip 4 and driving the LED light source 5 is the same as that of the one connector. 32 can be easily achieved simply by inserting a single connector socket or connector plug that forms a pair with this.

Of course, the image reading apparatus A can appropriately perform the reading operation of the original image. That is, as shown in FIG. 2, when the LED light source 5 is driven in a state where the document K is placed on the transparent plate 20, light emitted from any of the LED chips 50a to 50c is transmitted to the light guide member 1. The light enters the light guide member 1 from the end face 10E at one end in the longitudinal direction. Then, as described above, the light travels toward the other end portion in the longitudinal direction of the light guide member 1 while
The light is emitted from various portions of the side surface 10A substantially in the entire length region, and is efficiently linearly irradiated on the document surface in the image reading area S.
The light reflected by the document K is then focused by the condenser lens 6 and then received by the light receiving element 40 of the sensor IC chip 4 to obtain an image signal having a level corresponding to the amount of received light.

FIGS. 13 and 14 are schematic perspective views showing other examples of the resin package type light source. In addition,
In the drawings after FIG. 13, the same parts as those in the previous embodiment are denoted by the same reference numerals, and description thereof will be omitted.

The resin package type light source 5A shown in FIG.
Is a package in which only one LED chip 50d is resin-packaged with a packaging resin 52.
The first lead 51e on which the ED chip 50d is mounted and the L
A total of two electrodes 53 are formed by the second lead 51f connected to the ED chip 50d via the wire W. This resin package type light source 5A can emit white or another monochromatic light, and is suitable for use in reading a monochrome image. In addition, as the resin package type light source 5A, three types of light sources that emit light of respective colors of R, G, and B are prepared, and the three types of light sources 5A are combined to be used for reading a color image. it can.

The resin package type light source 5B shown in FIG.
Is a resin package of two LED chips 50e and 50f with a packaging resin 52, and a total of three electrodes 53 with three leads 51g to 51i.
Is formed. In this resin package type light source 5B,
By making the types of the two LED chips 50e and 50f different, for example, R and G, G and B, or B and R
Which emits two colors of light. Therefore, for example, by combining this resin package type light source 5B and one resin package type light source 5A that emits monochromatic light shown in FIG. 13, light of a total of three colors of R, G and B can be generated. , For reading color images.

As described above, the resin package type light source used in the present invention is a light source body (L
The specific number of ED chips) and the kind of emission color are not limited, and these are items that can be appropriately selected.

FIG. 15 is a sectional view showing another example of a resin package type light source used in the image reading apparatus according to the present invention. 16A and 16B are perspective views showing specific examples of the appearance. FIG. 17 is a cross-sectional view of a main part showing an example of a mounting structure of the resin package type light source shown in FIG.

A resin package type light source 5C shown in FIG.
Is provided with a plurality of electrodes 53a on a back surface 52c facing the front surface 52a of the packaging resin 52A in the thickness direction of the packaging resin 52A. The number of the electrodes 53a differs depending on the number of LED chips 50g to be resin-packaged, for example, as shown in FIGS. Each of the plurality of electrodes 53a has a side surface portion 52b at least a part of which forms a bottom surface when the light transmitting window portion 54 formed on the front surface portion 52a of the resin package type light source 5C is oriented substantially horizontally. So that the side portion 52 is located near
It is provided at a position closer to b.

As shown in FIG. 17, when the resin package type light source 5 C is mounted on the circuit board 3, when the light transmitting window 54 is set in a posture facing the end face 10 E of the light guide member 1, Although the electrode 53a cannot face the terminal portion 31 of the circuit board 3 directly, the electrode 53a can be made to approach an upright state on the side or above the terminal portion 31. Therefore, by mounting the solder 89 between the electrode 53a and the terminal portion 31 in a fillet-like manner, the resin package type light source 5C in which the conductive connection is achieved can be appropriately mounted. As described above, in the resin package type light source used in the image reading apparatus according to the present invention, the specific positions of the electrodes can be appropriately changed.

FIG. 18 is a cross-sectional view of an essential part showing another example of the combination structure of the light guide member and the resin package type light source constituting the image reading apparatus according to the present invention.

In the structure shown in the figure, the light guide member 1A is formed in a symmetrical shape, and the end faces 1 at both ends in the longitudinal direction are formed.
This is a structure in which light sources 5 and 5 are opposed to 0E and 10E, respectively. According to such a configuration, it is possible to cause light to enter the light guide member 1A from the two end surfaces 10E, 10E of the light guide member 1A, and then to emit the light from substantially the entire length region of the first side surface 10A. . Therefore, the amount of light incident on the light guide member 1A can be easily increased, and the amount of light irradiated on the image reading area can be increased.

In the above embodiment, the light guide members 1, 1A
Although the third side surface 10C and the fourth side surface 10D are formed as paraboloids, and the first side surface 10A is configured to exhibit the function of a convex lens, the present invention is not limited to this. In the present invention, for example, an elongated simple rectangular parallelepiped light guide member extending in a certain direction may be used as the light guide member. Even in the light guide member having such a configuration, the light is incident on the inside of the light guide member from the end face of the longitudinal direction end portion of the light guide member, so that the light is guided by the plurality of side surfaces extending in the longitudinal direction of the light guide member. While being reflected and traveling in the longitudinal direction of the light guide member, the light can be emitted to the outside from a fixed length region of the first side surface of the plurality of side surfaces.

However, as means for improving the efficiency of light incidence into the light guide member, it is preferable to configure, for example, as shown in FIG. That is, the configuration shown in the figure is such that the longitudinal end 19a of the light guide member 1B is
End face 10G formed to be thicker than the light source 5 and disposed opposite to each other.
Is larger than the cross-sectional area A2 of the general portion of the longitudinal middle portion 19b. As shown in FIG. 20, when the area A3 of the end face 10H at the longitudinal end of the light guide member 1C is set to a relatively small area similar to the intermediate part in the longitudinal direction,
Part of the light emitted from the light source 5 with a certain spread is not projected on the end face 10H, and there is a possibility that the amount of light supplied into the light guide member 1C may be reduced. However, with the configuration as shown in FIG. 19, as much as the area A1 of the end face 10G is formed, a large amount of light can be made to enter the light guide member 1B from the end face 10G.

As another means for increasing the efficiency of incidence of light into the light guide member, for example, a configuration as shown in FIG. 21 can be adopted. In the configuration shown in the figure, a concave portion 18 is formed in an end surface portion of a longitudinal end portion of the light guide member 1D, and the whole or a part of the light source 5 is accommodated and arranged in the concave portion 18. Also, at the longitudinal end of the light guide member 1D,
One or more curved or planar inclined surfaces 17 capable of reflecting light traveling from the light source 5 in the width direction or the vertical thickness direction of the light guide member 1D toward the longitudinal middle portion of the light guide member 1D are provided. ing. According to such a configuration, since the light source 5 is arranged in the recess 18, the light source 5
Even when light is emitted at a large spread angle, most of the light can enter the light guide member 1D. Further, the light enters the light guide member 1D and is inclined
The light that has reached 7 can be totally reflected toward the intermediate portion in the longitudinal direction of the light guide member 1D, and can be prevented from being unjustly emitted to the outside of the light guide member 1D.

In each of the above embodiments, the light source is opposed to the end face of the longitudinal end of the light guide member in any case, but the present invention is not limited to this. In the present invention, for example, as shown in FIG. 22, a tapered surface 16 having a width in the vertical thickness direction of the light guide member 1E is formed at the longitudinal end of the light guide member 1E separately from the end face 10E. The light source 5 may be opposed to the surface 16. Surface 16
A light-shielding layer 16a or a light-shielding member for preventing light transmission is provided as necessary on the side surface of the light-guiding member 1E that faces the light-guiding member 1E. Even with such a configuration, after light enters the light guide member 1E from the surface 16, the light can be advanced toward the intermediate portion in the longitudinal direction of the light guide member 1E. As described above, in the present invention, if light is incident on the light guide member from the surface as long as the surface has a width in the vertical thickness direction of the light guide member, the light is transmitted in the longitudinal direction of the light guide member. The light can be smoothly advanced, and the position of the outer surface where the light is incident can be variously changed.

In addition, the specific configuration of each part of the image reading apparatus and the resin package type light source according to the present invention can be variously changed in design. For example, in the above embodiment, the light emitted from the first side surface of the light guide member is directly irradiated to the image reading area. However, the present invention is not limited to this. The emitted light may be reflected by a reflection mirror or a light reflection sheet, or transmitted through another light guide member to irradiate the image reading area.
Further, the image reading apparatus according to the present invention can be configured as a contact-type image sensor used as a handy scanner, instead of being configured as a contact-type image sensor arranged to face the platen roller. A so-called flatbed type image sensor in which a circuit board on which a predetermined light source and a light receiving element are mounted and a case incorporating a light guide member are relatively movable in the sub-scanning direction with respect to a document placing plate for placing a document. It can also be configured as

[Brief description of the drawings]

FIG. 1 is a partially omitted cross-sectional view illustrating an example of an image reading apparatus according to the present invention.

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

FIG. 3 is a sectional view taken along the line III-III of FIG. 1;

FIG. 4 is an exploded perspective view of the image reading apparatus shown in FIG.

FIG. 5 is a schematic partial cross-sectional perspective view showing a light guide member used in the image reading apparatus shown in FIG.

FIG. 6 is a sectional view taken along line VI-VI of FIG.

FIG. 7 is an explanatory view showing an operation of the light guide member shown in FIG.

FIG. 8 is a perspective view of the LED light source used in the image reading apparatus shown in FIG. 1 as viewed from below.

FIG. 9 is a cross-sectional view of the LED light source shown in FIG.

FIG. 10 is a schematic perspective view showing the internal structure of the LED light source shown in FIG.

FIG. 11 is a cross-sectional view of a main part showing a structure of a mounting portion of the LED light source.

FIG. 12 is an exploded perspective view of a main part of the image reading apparatus shown in FIG.

FIG. 13 is a schematic perspective view showing another example of a resin package type light source.

FIG. 14 is a schematic perspective view showing another example of a resin package type light source.

FIG. 15 is a sectional view showing another example of a resin package type light source.

16 (a) and (b) are perspective views showing specific examples of the appearance of the resin package type light source shown in FIG.

17 is a cross-sectional view of a main part showing an example of a mounting structure of the resin package type light source shown in FIG.

FIG. 18 is a cross-sectional view of a main part showing another example of the combination structure of the light guide member and the resin package type light source that constitute the image reading device.

FIG. 19 is an explanatory view of a relevant part showing another example of the combination structure of the light guide member and the light source.

FIG. 20 is an explanatory view of a relevant part showing another example of the combination structure of the light guide member and the light source.

FIG. 21 is a main part explanatory view showing another example of the combination structure of the light guide member and the light source.

FIG. 22 is a main part explanatory view showing another example of the combination structure of the light guide member and the light source.

FIG. 23 is an explanatory diagram showing an example of a linear light source device used in a conventional image reading device.

24 is an exploded perspective view of a main part of the linear light source device shown in FIG.

[Explanation of symbols]

 1, 1A to 1E Light guide member 2 Case 3 Circuit board 4 Sensor IC chip 5 Resin package type LED light source 6 Condensing lens 7A First light reflection member 7B Second light reflection member 10A First side surface 10E, 10F End surface 30A , 30B conductive wiring part 40 light receiving element 50a to 50g LED chip 52 packaging resin 52a front part 52b side part 52c back part 53,53a electrode 54 light transmitting window part S image reading area A image reading device

Claims (10)

[Claims] A plurality of light receiving elements for receiving reflected light from an object to be read; a circuit board on which the plurality of light receiving elements are mounted in a row; A light guide member having a plurality of side surfaces extending in the direction, and a light source for projecting light on an outer surface portion having a width in the vertical thickness direction of the light guide member, and Light emitted and incident on the inside of the light guide member travels in the longitudinal direction of the light guide member from a fixed length region of a first side surface of the plurality of side surfaces of the light guide member. An image reading apparatus configured to emit light to the outside, wherein the light source has a light source body packaged in a resin package by a packaging resin forming a light-transmitting window portion in a front surface portion, and the packaging resin Electrodes are provided outside the The resin package type light source is mounted on the circuit board so that the electrode is electrically connected to a conductive wiring portion provided on the circuit board, and the light transmitting window portion is provided with the light guide. An image reading device, wherein the image reading device is set in a posture facing the outer surface portion of the optical member. 2. The method according to claim 1, wherein the light source body includes one or more LEDs.
The image reading device according to claim 1, wherein the image reading device is a chip, and the resin package type light source is a resin package type LED light source. 3. The image reading device according to claim 1, wherein the electrode of the resin package type light source is provided on a side surface of a packaging resin facing the circuit board. 4. An electrode of the resin package type light source is provided on a back surface portion of the packaging resin opposite to the front surface portion, and is located near a side surface portion of the packaging resin facing the circuit board. Claim 1 or 2
An image reading device according to claim 1. 5. A connector for connecting an external device is mounted on the circuit board, and the connector is connected to a conductive wiring portion which is connected to the plurality of light receiving elements and an electrode of the resin package type light source. The image reading device according to claim 1, wherein the plurality of conductive wiring portions are connected together. 6. The resin package type light source is provided so as to face an end face of one end in the longitudinal direction of the light guide member, and is provided between the one end and the other end in the longitudinal direction of the light guide member. The image reading device according to claim 1, further comprising a light reflecting unit configured to reflect light traveling to an end face toward the one end. 7. The image reading device according to claim 1, wherein the resin package type light source is provided to face each end face of both ends in the longitudinal direction of the light guide member. 8. The light guide member has an end surface area at a longitudinal end where the resin package type light source is opposed to the light guide member, and has an area larger than a cross-sectional area of a general portion at a longitudinal middle portion of the light guide member. 8. The image reading device according to claim 6, wherein said longitudinal end portion is formed thicker than said longitudinal middle portion. 9. A concave portion for accommodating the whole or a part of the resin package type light source is formed on an end face of a longitudinal end portion of the light guide member, and a longitudinal end of the light guide member is formed. The portion has a curved or planar inclined surface capable of reflecting light traveling from the resin package type light source in the lateral width direction or the vertical thickness direction of the light guide member toward the longitudinal middle portion of the light guide member. The image reading device according to claim 6, wherein the image reading device is provided. 10. A light emitting device comprising: a packaging resin in which one or a plurality of light source main bodies are resin-packaged; and an electrode which is electrically connected to the light source main body. A resin package type light source provided with a light-transmitting window for irradiating the light to the outside, wherein the electrode is formed of the packaging resin when the light-transmitting window is oriented in a substantially horizontal direction. A resin package type light source, which is provided on a side surface serving as a bottom surface of the light source.