JPH10190956A - Linear light source device, light transmission member used therefor, and image reader provided with linear light source employing the light transmission member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To emit a light to a linear region properly, while avoiding to the utmost an extended size of a linear light source device in the lengthwise direction. SOLUTION: A plurality of outer circumferential side faces 10A-10D extended in the lengthwise direction of a transparent member 10 are formed to an outer face of the transparent member 10 with a prescribed length, a light-transmitting member to be a light emission face that emits a light made incident onto the transparent member 10 in the lengthwise direction with respect to the outside of the transparent member 10, is used for the 1st side face 10A and a light incidence section 15 to make a light incident onto the transparent member 10 is provided to an end in the lengthwise direction of any one of outer circumferential side faces of the transparent member 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a linear light source device which can be suitably used as a document illumination for reading a document such as a so-called contact type image sensor, a light guide member used in the linear light source device, and a light guide for the same. The present invention relates to an image reading apparatus including a linear light source using a member.

[0002]

2. Description of the Related Art Conventionally, as an example of a linear light source device, there is one disclosed in, for example, JP-A-6-217084. As shown in FIG. 33 of the present application, the linear light source device described in the publication discloses a light guide member 1e made of a transparent member having a rectangular parallelepiped shape having a fixed length, and the end face at one longitudinal end portion of the light guide member 1e.
As e, a light source 9e is arranged to face the light incident portion 15e. The light guide member 1e has one side surface extending in the longitudinal direction as a light exit surface 12e.
Light scattering surface 1
4e.

In the linear light source device having the above structure, the light incident portion 1
The light that has entered the inside of the light guide member 1e from the light guide member 5e is diffusely reflected on the light diffuse reflection surface 14e, so that the diffusely reflected light can be emitted to the outside of the light guide member 1e from the light exit surface 12e. For this reason, the light exit surface 12e
Is approximately equal to the width of document D,
Light can be applied to the entire length region of the document D in the width direction.
According to such means, for example, as shown in FIG. 34, the number of light sources 9 is greatly reduced as compared with a means in which a large number of light sources 9 are provided at predetermined pitch intervals along the width direction of the document D, Production costs can be reduced.

[0004]

However, the conventional linear light source device has the following disadvantages.

That is, in the above-described conventional linear light source device, the end face of one end in the longitudinal direction of the light guide member 1e is a light incident portion 15e, and the light source 9e faces the light incident portion 15e. Must be provided in series. For this reason, the overall length dimension L of the linear light source device is increased by the amount that a space for disposing the light source 9e must be secured. Conventionally, as shown by the imaginary line in FIG. 33, a light source 9f may be additionally provided on the side of the other end in the longitudinal direction of the light guide member 1e. The overall length of the light source device is further increased.

On the other hand, in order to reduce the size of the image reading apparatus using the linear light source device, the size of the light guide member 1e in the longitudinal direction is more than the size of the light guide member 1e in the thickness direction or the width direction. It is strongly required to be smaller. For example, when manufacturing an image reading apparatus for an A4 width document, it is necessary that at least the entire length of the light guide member 1e be a large size substantially equal to the A4 width. This is because they tend to be bulky. However, as described above, conventionally, since the linear dimension of the linear light source device is large, such a demand cannot be sufficiently satisfied.

Conventionally, when a handy scanner is manufactured, a space area for disposing the light source 9e on the side of the light guide member 1e in the longitudinal direction becomes an area where an image cannot be read. , A relatively large dead space occurs. For this reason, when the conventional linear light source device is incorporated in a handy scanner and used, the handy scanner is inconvenient to use due to the large area where the image cannot be read by the handy scanner. As described above, conventionally, various inconveniences have been caused due to the large size of the entire linear light source device in the longitudinal direction.

The present invention has been devised in view of such circumstances, and irradiates a linear region with light while minimizing the lengthwise size of the linear light source device as much as possible. The task is to be able to perform the task appropriately.

[0009]

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

According to a first aspect of the present invention, there is provided a light guide member. In this light guide member, a plurality of outer peripheral side surfaces extending in the longitudinal direction of the transparent member are formed on an outer surface of a transparent member having a fixed length, and a first side surface of the plurality of outer peripheral side surfaces is formed inside the transparent member. A light guide member that is a light exit surface that emits light that travels in the longitudinal direction of the transparent member and emits the light to the outside of the transparent member. It is characterized in that it is provided at a longitudinal end of any outer peripheral side surface of the transparent member.

In the light guide member, the light incident portion may be provided at each of both longitudinal ends of the outer peripheral side surface.

[0012] In the light guide member provided by the first aspect of the present invention, the light incident on the transparent member from the light incident portion is totally reflected on the inner surfaces of the plurality of outer peripheral side surfaces of the transparent member while the transparent member is being reflected. , And the light can be sequentially emitted from the light emitting surface extending in the longitudinal direction of the transparent member to the outside of the transparent member. Therefore, this light guide member can function properly as a light guide member for a linear light source. The light incident portion is provided at a longitudinal end of an outer peripheral side surface extending in the longitudinal direction of the transparent member, and a light source that projects light into the transparent member is disposed on one side in a thickness direction or a width direction of the transparent member. What is necessary is just to arrange. As a result, unlike the conventional light guide member in which the light sources are arranged in series at the side of the longitudinal end, the total length in the longitudinal direction of the linear light source device including the light guide member and the light source is different. Can be appropriately prevented from becoming large, miniaturization of various devices such as a contact image sensor and a handy scanner configured using the linear light source device, and reduction of an area where an image cannot be read. A special effect is obtained in that it is possible to appropriately achieve the above.

[0013] In a preferred embodiment of the present invention, the transparent member has a longitudinal end formed with an inclined surface facing the light incident portion in the thickness direction or the width direction of the transparent member. It can be. In this case, the light incident portion is provided on the second side surface facing the first side surface in the thickness direction of the transparent member, and the inclined surface is provided continuously with a longitudinal end of the first side surface. And the inclined surface may be inclined so as to move away from the second side surface toward the center in the longitudinal direction of the transparent member. Further, instead of such a configuration, the light incident portion is provided on a third side surface of the transparent member connected to intersect with the first side surface, and the inclined surface is provided on the third side surface. The light guide member is connected to a longitudinal end of a fourth side surface facing the width direction of the light guide member, and the inclined surface extends toward the longitudinal center of the transparent member. It may be configured to be inclined away from the side surface. Further, the light incident portion is provided on the first side surface, and the inclined surface is provided continuously with a longitudinal end of a second side surface facing the first side surface in a thickness direction of the transparent member. And the inclined surface may be inclined so as to move away from the first side surface toward the center in the longitudinal direction of the transparent member.

According to such a configuration, the light incident from the light incident portion into the transparent member is reflected by the inclined surface,
The light can efficiently travel in the longitudinal direction of the transparent member. That is, when the outer surface such as the outer peripheral side surface of the transparent member is mirror-finished, when the incident angle of light on the outer surface is larger than the critical incident angle defined by the refractive index of the transparent member, all of the light rays are emitted. Is reflected. On the other hand, when the incident angle is smaller than the critical incident angle, the light beam is transmitted. The inclined surface is
When the light that has entered the transparent member from the light incident portion directly enters the inclined surface, the angle of incidence is increased, and this light is prevented from directly transmitting outside the transparent member. Further, the inclined surface also plays a role of reflecting the light and guiding the light in the longitudinal direction of the transparent member. Therefore, it is possible to suppress the light incident into the transparent member from being intensively emitted to the outside from a part of the region facing the light incident portion, to reduce the light emission loss, and to reduce the total length of the light emission surface. The amount of emitted light in the region can be made uniform.
As a result, for example, when the linear light source device provided with the light guide member is used as a light source of an image reading device, the illuminance over the entire length of the reading line on the document surface can be made uniform, and the reading caused by the variation in illuminance can be achieved. The effect is obtained that deterioration of image quality can be prevented.

In another preferred embodiment of the present invention,
The inclined surface may be a non-light-transmitting surface. The non-light-transmitting surface can be formed by depositing, plating, thermally transferring, or printing a glossy material on the inclined surface.

According to such a configuration, it is possible to more thoroughly prevent the light that has entered the transparent member from the light incident portion from being transmitted through the inclined surface and directly emitted to the outside. Therefore, the loss of light emission can be further reduced, and the amount of emitted light can be made more uniform over the entire length of the light emission surface.

In another preferred embodiment of the present invention,
An end face extending in the thickness direction and the width direction of the transparent member on one side of the light incident portion may be continuously provided at one end of the inclined surface.

According to this configuration, the light incident from the light incident portion into the transparent member can be efficiently reflected by the inclined surface and the end surface, and these portions are not formed as non-light-transmitting surfaces. Even in this case, it is possible to reduce the risk that light passes through these portions to the outside as it is. That is, when the entire area of the portion facing the light incident portion is formed as an inclined surface without providing the end surface at the longitudinal end portion of the transparent member, a region where the incident angle of light with respect to the inclined surface becomes smaller. There is a possibility that light will be transmitted to the outside from this part. However, by making this part an end face extending in the thickness direction and the width direction of the transparent member, the angle of incidence of light on this end face is increased, It is possible to reduce the amount of light that enters the transparent member from the portion and passes through the outside of the transparent member as it is. Therefore, it is preferable to reduce the loss of light emission and to make the amount of emitted light uniform over the entire length of the light emission surface.

In another preferred embodiment of the present invention,
The inclined surface may be configured as a convex curved surface.

According to this structure, the angle of incidence when the light incident from the light incident portion into the transparent member enters each part of the inclined surface is characteristic in that the inclined surface is a convex curved surface. Can be increased. Therefore, it is possible to reduce the ratio of the light incident on the inclined surface at an incident angle smaller than the critical incident angle, and to reduce the amount of light transmitted through the inclined surface and emitted to the outside of the transparent member. For this reason, it is preferable that the loss of light emission is reduced and the amount of emitted light is made uniform over the entire length of the light emission surface.

In another preferred embodiment of the present invention,
The first side surface may be configured to be a mirror-like flat surface.

According to such a configuration, of the light incident on the transparent member, the light incident on the first side surface at an angle larger than the predetermined critical reflection angle is totally reflected. Can be advanced in the longitudinal direction of the transparent member. On the other hand, light incident on the first side surface at an angle smaller than the predetermined critical reflection angle can be transmitted to the outside of the transparent member. Therefore, the first side surface can appropriately function as a light reflection surface that allows light incident on the transparent member to travel in the longitudinal direction of the transparent member and a light emission surface that emits light to the outside of the transparent member. .

In another preferred embodiment of the present invention,
The width of the first side surface may be smaller than the width of the second side surface facing the first side surface in the thickness direction of the transparent member.

According to such a configuration, light incident on the transparent member and reflected by the second side surface can be transmitted through the first side surface having a width smaller than that of the second side surface. , The density of light emitted from the first side surface can be increased, and the illuminance of the irradiated surface on the line can be increased.

In another preferred embodiment of the present invention,
A second side facing the first side surface in a thickness direction of the transparent member;
The side surface may have a plurality of concave portions, and the concave portions may have a curved or flat inclined surface facing obliquely to the light emitting surface. it can.

According to such a configuration, when the light incident on the transparent member is made to travel in the longitudinal direction of the transparent member, the light is reflected by the inclined surface of the concave portion, whereby the light of the light is reflected. By changing the traveling direction abruptly, the light can be incident on the first side surface at an angle smaller than a predetermined critical reflection angle, and can be transmitted through the first side surface. Therefore, light traveling in the longitudinal direction of the transparent member can be efficiently emitted to the outside via the first side surface.

In another preferred embodiment of the present invention,
A second side facing the first side surface in a thickness direction of the transparent member;
The substantially entire area of the side surface or the selected partial area may be configured as a light diffuse reflection area for performing diffuse reflection of light. The light diffuse reflection region is a region where a paint that performs light scattering reflection is applied to the second side surface, a region where a tape piece that performs light scattering reflection is adhered, or a region where the surface of the second side surface is an uneven rough surface. May be adopted.

According to such a configuration, the light traveling in the longitudinal direction of the transparent member reaches the light diffuse reflection area on the second side surface,
Due to the irregular reflection, a part of this light can be made incident on the first side surface at an angle smaller than a predetermined critical reflection angle, and can be transmitted through the first side surface. Therefore, even with such a configuration, light traveling in the longitudinal direction of the transparent member can be efficiently emitted to the outside from the first side surface.

In another preferred embodiment of the present invention,
A second side facing the first side surface in a thickness direction of the transparent member;
The side surface may be configured to be inclined or curved so that a distance between the side surface and the first side surface decreases as the distance from the light incident portion increases.

According to such a configuration, the amount of light emitted from the first side surface can be made more uniform. That is, the amount of light traveling in the longitudinal direction of the transparent member tends to gradually decrease as the distance from the light incident portion increases, but in the above configuration, the second side surface and the second Since it is inclined or curved so that the distance to one side is reduced, light can be efficiently incident on the second side even in a region far from the light incident part. The reflected light can be appropriately emitted from the first side surface. For this reason, in the first side surface, the amount of light emitted from a region far from the light incident portion is prevented from becoming extremely small as compared with the amount of light emitted from other regions, and the amount of emitted light is made uniform. I can do it.

According to the second aspect of the present invention, there is provided a light guide member having a configuration different from that of the light guide member provided by the first aspect of the present invention. In this light guide member, a plurality of outer peripheral side surfaces extending in the longitudinal direction of the transparent member are formed on an outer surface of a transparent member having a fixed length, and a first side surface of the plurality of outer peripheral side surfaces is formed inside the transparent member. A light guide member serving as a light exit surface that emits light that travels in the longitudinal direction of the transparent member and enters the outside of the transparent member, and an inclined surface is formed at a longitudinal end of the transparent member. In addition, the inclined surface is characterized in that the inclined surface is a light incident portion for allowing light to enter the transparent member.

[0032] In the light guide member, the inclined surface may be a longitudinal end of a second side facing the first side and a thickness direction of the transparent member, and a third side may be connected in a direction intersecting the first side. It is possible to adopt a configuration in which the side surface is connected to the longitudinal end portion or the longitudinal end portion of the first side surface.

In the light guide member provided by the second aspect of the present invention, light incident on the transparent member from an inclined surface formed at a longitudinal end of the transparent member is provided on a plurality of outer peripheral side surfaces of the transparent member. While being totally reflected on the inner surface of the transparent member, the light travels along the entire region in the longitudinal direction of the transparent member, and the light can be sequentially emitted from the light emission surface to the outside of the transparent member. Therefore, also in this light guide member, similarly to the light guide member provided by the first aspect of the present invention,
It can function properly as a light guide member for a linear light source. The inclined surface formed at the longitudinal end of the light guide member,
Because it is a light incident portion for allowing light to enter the transparent member, the light source that projects light into the light guide member is also disposed on one side in the thickness direction or width direction of the transparent member. Good. As a result, unlike the conventional transparent member in which the light sources are arranged in series on the side of the longitudinal end, the overall length of the linear light source device using the light guide member in the longitudinal direction is increased. Can be appropriately avoided, and an excellent effect such as downsizing of the image reading device configured by incorporating the linear light source device can be obtained.

According to a third aspect of the present invention, there is provided a linear light source device using the light guide member provided by the first or second aspect of the present invention. This linear light source device is characterized in that it includes any one of the above-described light guide members and a light source facing the light incident portion of the light guide member.

As the light source, an LED can be used, and more specifically, a combination of LEDs of three colors of R, G, and B, or a white LED can be used. In the light source, for example, an LED may be attached to a light incident portion of the light guide member using an adhesive or the like, or an LED mounted on a substrate may be adjacent to the light incident portion of the transparent member. .

According to a fourth aspect of the present invention, there is provided an image reading apparatus using the linear light source device provided by the third aspect of the present invention. This image reading apparatus irradiates light from a light source device onto a document arranged opposite to the document reading surface, and reflects reflected light from the document on a reading line set on the document reading surface in the reading line direction. An image reading device in which a plurality of light receiving elements receive light, wherein the linear light source device provided by the third aspect of the present invention is used as the light source device.

In the image reading apparatus, the linear light source device and the light receiving element are housed in a movable casing that can be gripped, and the whole can be configured as a handy scanner.

According to the linear light source device and the image reading apparatus provided by the third and fourth aspects of the present invention, the light guide provided by the first or second aspect of the present invention is provided. The same effect as obtained with the optical member can be expected.

[0039]

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 front view showing an example of a light guide member 1 according to the present invention and a linear light source device A using the same. FIG. 2 is a right side view of FIG. FIG. 3 is a cross-sectional view of FIG.
It is I-III sectional drawing. FIG. 4 is an enlarged front view of a main part of FIG. FIG. 5 shows the light guide member 1 and the linear light source device A.
It is explanatory drawing which shows the effect | action of.

The light guide member 1 of this embodiment is, for example, PM
A transparent member 10 obtained by molding an acrylic transparent resin such as MA occupies the main part. This transparent member 10
Is a long and narrow bar having a certain dimension in the longitudinal direction, as is well shown in FIG.
A first side surface 10A, a second side surface 10B,
It has a third side surface 10C, a fourth side surface 10D, end surfaces 10E and 10F at both ends in the longitudinal direction, and an inclined surface 2. The first side face 10A and the second side face 10B face each other in the vertical thickness direction of the transparent member 10, and the width of the first side face 10A is smaller than the width of the second side face 10B.
The third side surface 10C and the fourth side surface 10D are connected to the transparent member 1
0 in the width direction.

The first side surface 10A is preferably a mirror-like flat surface, and the first side surface is a light emitting surface 12 as described later. In the present embodiment, the third side surface 10C and the fourth side surface 10D are also mirror-like planes. However, the third side face 10C and the fourth side face 1
Regarding 0D, a non-light-transmitting surface may be used, for example, by vapor-depositing a metal on those surfaces.

The term "mirror surface" in the present invention does not necessarily mean that the surface is positively polished. For example, when the transparent member 10 is resin-molded using a mold, a relatively smooth surface obtained by the resin molding is also included in the mirror-like surface according to the present invention.
If the surface of the transparent member is a mirror surface, it is possible to reflect all light rays incident at an angle larger than the total reflection critical angle specified by the material of the transparent member with respect to this surface, Light rays incident at an angle smaller than the critical angle for total reflection can be transmitted.

A light incident part 15 is provided at one longitudinal end of the second side surface 10B. In the present embodiment, the light incident portion 15 is formed as a smooth surface that can face an LED lamp 3 described later.

The light incident portion 1 is provided on the second side surface 10B.
In a region excluding 5, a plurality of mirror-like plane portions 13;
The plurality of concave portions 14 are provided alternately at predetermined pitch intervals. Each of the plurality of concave portions 14 is formed, for example, in an arc-shaped cross section, and has a curved inclined surface 14a that is inclined (non-parallel) to the first side surface 10A. In addition, the second side surface 10 </ b> B is
5 is formed as an inclined surface that gradually reduces the thickness of the transparent member 10 as the distance from the transparent member 5 increases.

The inclined surface 2 is connected to one end of the first side surface 10A in the longitudinal direction so as to face the light incident portion 15, and the second surface is shifted toward the center of the transparent member 10 in the longitudinal direction. The inclined surface moves away from the side surface 10B.

The inclined surface 2 is a mirror-like flat surface, but its outer surface is a non-light-transmitting surface that does not transmit light. Similarly, the end surface 10F connected to the inclined surface 2 is also a non-light-transmitting surface. The inclined surface 2 and the end surface 10F
For example, as shown in FIG. 4, a glossy material such as Al, Cr, or Ag is vapor-deposited on the surfaces of the inclined surface 2 and the end surface 10F to form a non-light-transmitting surface. Means for forming the film 5 can be employed. Also,
Instead of such means, the inclined surface 2 and the end surface 10
Means for plating, thermally transferring, or printing a glossy material on F, or means for attaching a glossy member can be employed.

The end face 10E is formed on the inclined face 2 or the end face 1
Similarly to OF, for example, a glossy material is vapor-deposited on the surface to make the surface non-translucent. In this way, light does not pass through the end face 10E as it is,
Light emission loss can be reduced.

The linear light source device A includes a plurality of types of LEDs.
The lamp 3 (3 a to 3 c) is configured to be disposed to face the light incident portion 15 of the light guide member 1. As the plurality of LED lamps 3 (3a to 3c), R, G,
B (red, green, blue) are used, which are provided in a line in the width direction of the light guide member 1, as best seen in FIG.

Next, the operation of the light guide member 1 and the linear light source device A will be described.

In FIG. 2, a plurality of LED lamps 3 (3
a) to 3c), when any one of the LED lamps 3 emits light, as shown in FIG. 4 and FIG.
Light enters the transparent member 10 from the light incident portion 15 with an appropriate spread angle. Most of the light reaches the inclined surface 2 facing the light incident portion 15. However, this slope 2
Is a non-light-transmitting surface, the entire amount of light reaching the inclined surface 2 is reflected and travels in the longitudinal direction of the transparent member 10. Of course, such total reflection of light is caused by the end face 10F.
It is also done in. Therefore, much of the light that has entered the transparent member 10 is prevented from directly exiting the transparent member 10 from the inclined surface 2 and the end surface 10F. Further, the light incident on the transparent member 10 from the light incident portion 15 includes light that directly reaches the first side surface 10A,
In this case, the incident angle of light on the first side surface 10A can be an incident angle larger than a predetermined critical angle for total reflection.
Therefore, it is possible to prevent the light from being intensively emitted in a region of the first side surface 10A that is close to the light incident portion 15. Most of the light that directly reaches the first side surface 10A is totally reflected by the first side surface 10A,
Again, the light travels in the longitudinal direction of the transparent member 10.

As described above, after all, most of the light that has entered the transparent member 10 from the light incident portion 15 travels in the longitudinal direction of the transparent member 10, but this light is mainly transmitted to the first side surface 10 A and the second side surface 10 B. And the total reflection is repeated in
0 to the other end in the longitudinal direction. When light is incident on the second side surface 10B, the light is totally reflected on the flat portion 13. On the other hand, most of the light that has reached the inclined portion 14a of the concave portion 14 has a sudden change in the course of the light, and is incident on the first side surface 10A at an incident angle smaller than the critical angle for total reflection. Increase the possibility of light incidence. Therefore, the first side surface 10 is reflected by the inclined surface 14a.
Most of the light traveling in the direction A is transmitted through the first side surface 10A,
The light is emitted to the outside of the transparent member 10. Therefore, even though the light incident portion 15 is provided at the longitudinal end of the second side surface 10B, light can be emitted almost uniformly from the entire length region of the light emitting surface 12 in the longitudinal direction.

On the other hand, as described above, the light incident portion 15
, Specifically, light leakage is suppressed from the inclined surface 2 and the end surface 10F. As a result, light can be intensively emitted from the entire length region of the first side surface 10A so that there is no large variation in the amount of light.
Will function properly as a linear light source that can irradiate light uniformly to various portions of a desired linear region having a certain length. The first side surface 10A that emits light is narrower than the second side surface 10B, and emits light reflected by the second side surface 10B and incident on the first side surface 10A to the outside in a form condensed into a small width. Therefore, it is more convenient to increase the illuminance of a desired linear region.

In the linear light source device A, the LED lamp 3 is disposed so as to face the second side surface 10 B of the transparent member 10.
The LED lamp 3 does not protrude outside the end face 10F. Therefore, the overall length in the longitudinal direction of the linear light source device A is the same as the overall length of the transparent member 10, and it is possible to appropriately avoid a large bulk in the longitudinal direction.

FIG. 6 is a sectional view showing an example of an image reading apparatus B using the linear light source device A.

The image reading apparatus B is configured as a so-called contact type color image sensor. The image reading device B has an image reading surface 42 made of a transparent glass plate on the upper surface of a casing 41, and a platen 43
The image of the document D conveyed while being backed up by the scanner is read line by line.

A substrate 44 is mounted on the lower surface of the cable 41, and a plurality of image sensor chips 45 having a predetermined number of light receiving elements are mounted on the substrate 44 in a row. For example, a document with A4 width
In order to read at a reading density of mm, 1,728 light receiving elements are arranged at a pitch of 125 μm. For example, 96 light receiving elements are integrally formed in one image sensor chip 45. Therefore, in this case, a total of 18 image sensor chips 45 are arranged on the substrate.

The plurality of image sensor chips 45 are arranged vertically below the reading line L set on the image reading surface 42, and a lens is provided between the reading line L and the image sensor chip 45. Array 4
6 are arranged. The lens array 46 focuses the image on the reading line L on 1728 light receiving elements arranged on the plurality of image sensor chips 45 at the same magnification as the erect image.

Below the image reading surface 42 in the casing 41, the linear light source device A is disposed in a space beside the lens array 46. In this case, the center line L1 in the left-right width direction of the light guide member 1 is disposed with the reading line L on the image reading surface 42 as a target.

The light emitted from the first side surface 10A of the light guide member 1 efficiently irradiates the original D on the reading line L. In this case, the LEDs 3a to 3c of each color are sequentially switched and lit. The document D is sent in the sub-scanning direction at a predetermined pitch, and image data for each of R, G, and B colors of the document image for each line is sequentially read by the image sensor chip 45.

In the image reading apparatus B, R,
Regardless of whether the G or B LED lamp 3 is used, it is possible to irradiate the entire area of the reading line of the document D with an equal amount of light in various places. Therefore, it is possible to reduce a change in the color tone of the read image due to a variation in the illuminance of the read line, and to improve the quality of the read image. As described above, the linear light source device A
The LED lamp 3 is arranged on the side of the light guide member 1 in the thickness direction, that is, below the light guide member 1, and it is necessary to arrange the light source on the side of the longitudinal end of the light guide member 1. Since there is no need, there is no need to secure an extra space beside the longitudinal end of the linear light source device A, and the image reading device B can be downsized.

FIG. 7 is a perspective view showing another example of the image reading device Ba according to the present invention. FIG. 8 is a perspective view showing the state of use.

The image reading device Ba is configured as a handy scanner, and incorporates the linear light source device A and other necessary devices (not shown) in a movable movable casing 41A. It is composed of The basic configuration of the device incorporated inside the casing 41A is the same as that of the image reading device B described with reference to FIG. Therefore, the detailed description is omitted for convenience.

In the image reading device Ba of the handy scanner type, the light guide member 1 has L
Because there is no need to provide the ED lamp 3, the end face 41a of the casing 41A extends from the image reading surface 42A.
The dimension La of the image unreadable area up to the point can be made very small. Specifically, when the image reading device Ba is designed to support the A4 width, the dimension La can be reduced to 5 mm or less. Therefore, as shown in FIG. 8, for example, when reading an image of a predetermined page of the book m using the image reading device Ba, the image readable area F of the image reading device Ba is bound to the binding of the book m. It is possible to approach the portion m1, so that the whole or substantially the entirety of the desired image can be read appropriately.

FIG. 9 is a side view of a main part showing another example of the light guide member and the linear light source device according to the present invention. In the configuration shown in the figure, an LED lamp is not used as a light source.
3A is used. On the other hand, the transparent member 10
The second side surface 10B is provided with a concave portion 16 in which the LED 3A can be arranged, and this portion serves as a light incident portion 15A.

According to such a configuration, when positioning the light source with respect to the transparent member 10, the LED
Since it is sufficient to dispose the 3A, the positioning thereof is facilitated. As described above, in the present invention, a concave portion for disposing a desired light source may be formed in the transparent member, and the light source is not limited to the LED lamp.

FIGS. 10 to 12 are front views of a main part showing another example of the inclined surface formed on the transparent member constituting the light guide member according to the present invention.

In the configuration shown in FIG.
5 is formed in the entire length region extending between the second side surface 10B and the first side surface 10A. Further, a non-light-transmitting film or the like is not formed on the outer surface of the inclined surface 2A, and is a mirror-like plane similar to the first side surface 10A. According to such a configuration, the transparent member 10
Of the light incident on the inside, the light incident on the inclined surface 2A at a large incident angle is totally reflected and can travel in the longitudinal direction of the transparent member 10. On the other hand, light incident on the inclined surface 2A at a small incident angle can be transmitted to the outside of the transparent member 10 as it is. Therefore, in the above configuration, the inclined surface 2A can function as a light emitting surface. Thus, in the present invention, the inclined surface may be the light emitting surface.

In the configuration shown in FIG.
The inclined surface 2B is formed such that an end face 10F extending in the thickness direction and the width direction of the transparent member 10 from 0B is formed with a relatively large area. According to such a configuration, it is possible to cause light to enter the inclined surface 2B at a relatively large incident angle and perform total reflection thereof, and similarly, to the end face 10F, a relatively large angle is applied. Light can be made incident at an incident angle to perform total reflection. Therefore, if such a configuration is adopted, light can efficiently travel in the longitudinal direction of the transparent member 10 even when the outer surfaces of the inclined surface 2B and the end surface 10F are not formed as non-light-transmitting surfaces. Become.

In the configuration shown in FIG. 12, the inclined surface 2C
Is formed as a convex curved surface having an appropriate radius of curvature R. According to such a configuration, the transparent member 10 is moved from the light incident portion 15 by an amount corresponding to that the inclined surface 2C is curved in a convex shape.
It is possible to increase the angle of incidence when the light entering the inside enters each part of the inclined surface 2C. Therefore,
Even when the inclined surface 2C is not a non-light-transmitting surface, there is an advantage that the ratio of light incident on the transparent member 10 as it is transmitted through the inclined surface 2C and emitted to the outside can be reduced. Can be

FIGS. 13 to 15 are perspective views showing the positional relationship between the light exit surface, the light entrance portion, and the inclined surface of the light guide member according to the present invention. That is, the configuration shown in FIG.
A light incident portion 15 is provided on a second side surface 10B facing the first side surface 10A of the transparent member 10 serving as the light emitting surface 12 in the thickness direction, and the light guide member 1 described with reference to FIGS.
It is a configuration that matches. 14 and FIG.
In the configuration shown in FIG. 5, the light incident portion 15 is provided on another outer peripheral side surface of the transparent member 10.

Specifically, in the configuration shown in FIG. 14, a light incident portion 15 is provided at a longitudinal end of a third side surface 10C connected to a direction intersecting with the first side surface 10A of the transparent member 10. The inclined surface 2D is provided continuously to the longitudinal end of the fourth side surface 10D that faces the third side surface 10C and the transparent member 10 in the width direction. The inclined surface 2D is inclined so as to move away from the third side surface 10C toward the central portion in the longitudinal direction of the transparent member 10. Even in such a configuration, most of the light that has entered the transparent member 10 from the light incident part 15 can be totally reflected by the inclined surface 2D and can travel in the longitudinal direction of the transparent member 10. Then, during this progress, it is possible to emit a substantially uniform amount of light from various parts of the first side surface 10A to the outside of the transparent member 10.

In the configuration shown in FIG. 15, the transparent member 1
The light incident portion 15 is provided at the longitudinal end of the first side surface 10A of the first slim, and the inclined surface 2E is continuously provided at the longitudinal end of the second side surface 10B. The inclined surface 2 </ b> E
0, it is inclined so as to move away from the first side surface 10A as it goes toward the center in the longitudinal direction. Also in such a configuration, the light incident on the transparent member 10 from the light incident portion 15 is totally reflected by the inclined surface 2E, travels in the longitudinal direction of the transparent member 10, and goes from various parts of the first side surface 10A to the outside. It can be emitted.

As described above, in the present invention, the light incident portion may be provided on any of the plurality of outer peripheral side surfaces formed on the transparent member. Of course, in the present invention, the outer peripheral side surface of the transparent member is not limited to the above-described first, second, third, and fourth side surfaces having a total of four outer peripheral side surfaces. It may be a polygonal cross section having six side surfaces. Further, the specific cross-sectional shape of the transparent member may be a shape in which the first side surface 10A and the second side surface 10B are formed to have the same width, for example, as in a transparent member 10a shown in FIG. Also, like the transparent member 10b shown in FIG. 17, the third side surface 10C and the fourth side surface 10E are curved surfaces, and the first side surface 10A and the second side surface 10B are mutually separated in the width direction of the transparent member 10b. The shape may be deviated.

FIGS. 18 to 21 are main part front views showing other examples of the second side surface formed on the light guide member according to the present invention.

In the configuration shown in FIG. 18, the transparent member 1
A plurality of concave portions 14A having a triangular cross section are provided at predetermined intervals on the second side surface 10B. In the present invention, even when such a configuration is employed, light traveling in the longitudinal direction of the transparent member 10 is not reflected by the concave portion 14A.
When the light reaches the flat inclined surface 14b, the angle of travel of the light is changed abruptly so that the light enters the first side surface 10A at an incident angle smaller than the critical angle of total reflection of the first side surface 10A. Light can be emitted from the first side surface 10A.

In the structure shown in FIGS. 19 and 20, a plurality of light scattering regions 17 or 17A for scattering and reflecting light are formed at predetermined intervals on the second side surface 10B of the transparent member 10, and the plurality of light scattering regions 17 or 17A are formed at predetermined intervals. Light diffuse reflection area 17
Alternatively, a mirror-like flat surface portion 13 is provided between 17A. The light diffuse reflection region 17 shown in FIG. 19 is provided, for example, by applying a coating having light scattering reflection to the second side surface 10B, or by attaching a tape piece having light scattering reflection to the second side surface 10B. ing. Light diffuse reflection area 1
7 is preferably a white surface, but other colors may be used. On the other hand, the light diffuse reflection area 17 shown in FIG.
A is provided by forming the surface of the second side surface 10B as an uneven rough surface.

In the means shown in FIGS. 19 and 20, light that travels in the longitudinal direction of the transparent member 10 is scattered and reflected in the light diffuse reflection area 17 or 17A of the second side face 10B, so that part of the light is transmitted to the second side face 10B. The light can be incident on one side surface 10A at an incident angle smaller than the critical angle for total reflection. Therefore, even by such means, light traveling in the longitudinal direction of the transparent member 10 can be efficiently emitted from the first side surface 10A to the outside.

The irregular reflection regions 17, 17A and the concave portions 14, 14A described above may be provided on the second side face 10B at a constant pitch, but the present invention is not limited to this. For example, the irregular reflection areas 17, 17A and the concave portions 14, 14
The pitch interval of each of A may gradually decrease as the distance from the light incident portion increases, and the area ratio with respect to the flat portion 13 may gradually increase as the distance from the light incident portion 15 increases. In this way, relatively weak light is applied to the first side surface 1 in a region far from the light incident portion 15.
0A can be efficiently emitted to the outside of the transparent member 10, and the advantage that the amount of emitted light in the entire length region of the first side surface 10A in the longitudinal direction can be made more uniform can be obtained.

In the configuration shown in FIG. 21, the transparent member 1
Substantially the entire surface of the second side surface 10B is a light diffuse reflection region 17. In the invention of the present application, the first configuration is also provided by such a configuration.
It is possible to appropriately emit light from the side surface 10A.

FIGS. 22 to 25 are front views showing other examples of the light guide member and the linear light source device according to the present invention.

In the structure shown in FIG.
The second side surface 10B opposite to the first side surface 10A, which is the light emission surface 12 of the first side surface 10c, is a convex curved surface having an appropriate radius of curvature Ra.
And the second side surface 10B are formed so that the distance between them gradually decreases. According to the present invention, even with such a configuration, the amount of light incident on the second side surface 10B is increased in a region far away from the light incident portion 15, and the light reflected by the second side surface 10B is transmitted to the first side surface 10B. It is possible to efficiently emit the light from 10A to the outside. in this way,
In the present invention, the second distance increases as the distance from the light incident portion 15 increases.
It is preferable to incline the side surface 10B so as to approach the first side surface 10A, but the present invention is not limited to this. In the present invention, for example, as shown in FIG. 23, the first side surface 10A and the second side surface 10B of the transparent member 10d may be formed substantially in parallel.

The configuration shown in FIG. 24 is the same as that shown in FIGS.
Light guide member 1 and linear light source device A described in
The unit is configured to be continuous in the longitudinal direction by two units. That is, the light guide member 1A shown in FIG.
Are provided with light incident portions 15, 15 at both ends in the longitudinal direction of the second side surface 10B of the transparent member 10e, and provided with inclined surfaces 2, 2 at positions facing these light incident portions 15, 15. Have been. Further, the light incident portion 15,
LED lamps 3 and 3 are provided near each of the LED lamps 15.

According to such a configuration, the transparent member 10e
Even if the overall length in the longitudinal direction is very large,
Light enters the transparent member 10e from each of the two light incident portions 15 and 15 so that the transparent member 10
It is possible to emit a sufficient amount of light from the entire length of the first side surface 10A of e. In the case where the overall length of the transparent member is large, if only one light incident portion is provided,
In some cases, the amount of light incident on the transparent member may be insufficient, and a sufficient amount of light may not be emitted from both longitudinal ends of the first side surface. Can be eliminated.

In the configuration shown in FIG. 24 as well, it is preferable that the second side surface 10B is inclined so as to approach the first side surface 10A as the distance from the light incident portion 15 increases. In this case, for example, like the light guide member 1B shown in FIG. 25, the second side surface 10B of the transparent member 10f can be formed as a convex curved surface having an appropriate curvature radius Rb. However, the present invention is not limited to this. For example, as described in FIG. 23, the second side surface of the transparent member may be a surface substantially parallel to the first side surface.

FIG. 26 is a front view showing another example of the light guide member and the linear light source device according to the present invention.

The light guide member 1C shown in FIG.
The two inclined surfaces 6 and 7 are formed at one end in the longitudinal direction of g, and the ends in the longitudinal direction are formed in a sharp shape having a substantially mountain shape in a front view. The inclined surface 6 has one end connected to the second side surface 10B of the transparent member 10g, and the inclined surface 7 has one end connected to the first side surface 10A. The inclined surface 6 has a light incident portion 15B.
The LED lamp 3 is arranged to face the light incident portion 15B.

In the linear light source device using the light guide member 1C, the light incident on the transparent member 10g from the light incident portion 15B is transmitted to various portions such as the inclined surface 7, the first side surface 10A, and the second side surface 10B. , And the light can travel in the longitudinal direction of the transparent member 10g. In this way, light traveling in the longitudinal direction of the transparent member 10g can be emitted to the outside from various parts of the first side surface 10A. Therefore, even in the case where the light guide member 1C having the above configuration is used, it is possible to appropriately irradiate a desired line-shaped surface to be irradiated with light.
In the light guide member 1C, the LED
Since the lamps 3 are arranged to face each other, this LE
The overall length of the D lamp 3 does not increase outside the end of the transparent member 10g, and the dimension Lb of the LED lamp 3 protruding outside the longitudinal end of the transparent member 10g can be made extremely small. Therefore, even in the linear light source device using the light guide member 1C, the overall length dimension is not large and bulky.

In the light guide member 1C described above,
For example, by making the inclined surface 7 a non-light-transmitting surface, it is possible to completely prevent light from passing through the inclined surface 7 and to eliminate light leakage. As the means for making the inclined surface 7 a non-light-transmitting surface, the same means as the means for making the inclined surface 2 a non-light-transmitting surface described in FIG.

FIGS. 27 to 29 are main part front views showing another example of the inclined surface which is the light incident portion of the light guide member according to the present invention. In the configuration shown in FIG.
The inclined surface 6A, which is 5B, is formed over the entire area from the first side surface 10A to the second side surface 10B of the transparent member 10g. According to such a configuration, it is possible to increase a space for disposing the LED lamp 3 in a region near the longitudinal end of the transparent member 10g, and the LED lamp 3 is provided at the longitudinal end of the transparent member 10g. It is possible to further reduce the dimension that largely protrudes outward. However, the present invention is not limited to this. For example, as shown in FIG.
The inclined surface 6B may have a relatively small area so as to leave 0G.

In the configuration shown in FIG.
The inclined surface 6C of the transparent member 10g to be formed 5B is a curved surface which is concavely curved with an appropriate curvature radius Rc. Even with such a configuration, it is possible to increase the space for disposing the LED lamp 3 in the vicinity of the longitudinal end of the transparent member 10g, and the LED lamp 3
The size that protrudes outside the longitudinal end of g can be made smaller or not protrude.

FIGS. 30 to 32 are perspective views of a main part showing an example of the positional relationship between the light emitting part, the light incident part, and the light source of the light guide member according to the present invention.

The structure shown in FIG. 30 is similar to the light guide member 1C described with reference to FIG.
The configuration is such that the inclined surface 6 connected to the side surface 10B is a light incident portion 15B. On the other hand, the configuration shown in FIG. 31 is a configuration in which an inclined surface 6D connected to the third side surface 10C of the transparent member 10g is formed, and the inclined surface 6D is used as the light incident portion 15B. In addition, the configuration shown in FIG.
An inclined surface 6E connected to the side surface 10A is formed, and the inclined surface 6E is used as a light incident portion 15B. In the present invention, in any of the configurations shown in FIGS. 30 to 32, the light incident on the transparent member 10g from the light incident portion 15B travels in the longitudinal direction of the transparent member, and the first side surface 10A It is possible to emit light appropriately.
In the present invention, any of the above embodiments may be employed.

In addition, the specific configuration of each part of the light guide member, the linear light source device, and the image reading device according to the present invention is not limited to the above-described embodiments, and various design changes can be made. In order to support a so-called monochrome image reading application that does not support color image reading, R,
It is not necessary to use a light source combining a total of three colors of G and B, and a light source of a single color may be used. In this case, it is preferable to use a white light source. Further, the light guide member and the linear light source device according to the invention of the present application are not limited to being used as a linear light source of an image reading device, and are used for various applications such as indoor lighting, vehicle interior lighting, and decorative lighting. It is possible. In this case, the most suitable one is selected for the size of the transparent member and the type of the light source.

[Brief description of the drawings]

FIG. 1 is a front view showing an example of a light guide member according to the present invention and a linear light source device using the same.

FIG. 2 is a right side view of FIG.

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

FIG. 4 is an enlarged front view of a main part of FIG.

FIG. 5 is an explanatory view showing the operation of the light guide member and the linear light source device.

FIG. 6 is a cross-sectional view illustrating an example of an image reading device using the linear light source device.

FIG. 7 is a perspective view showing another example of the image reading apparatus according to the present invention.

FIG. 8 is a perspective view showing a use state of the image reading apparatus shown in FIG. 7;

FIG. 9 is a main part side view showing another example of the light guide member and the linear light source device according to the present invention.

FIG. 10 is a front view of a main part showing another example of the inclined surface formed on the transparent member constituting the light guide member according to the present invention.

FIG. 11 is a main part front view showing another example of the inclined surface formed on the transparent member constituting the light guide member according to the present invention.

FIG. 12 is a front view of a main part showing another example of the inclined surface formed on the transparent member constituting the light guide member according to the present invention.

FIG. 13 is a perspective view showing a positional relationship among a light exit surface, a light entrance portion, and an inclined surface of the light guide member according to the present invention.

FIG. 14 is a perspective view showing a relationship between a light exit surface, a light entrance portion, and an inclined surface of the light guide member according to the present invention.

FIG. 15 is a perspective view showing a relationship between a light exit surface, a light entrance portion, and an inclined surface of the light guide member according to the present invention.

FIG. 16 is a sectional view showing another example of the transparent member constituting the light guide member according to the present invention.

FIG. 17 is a sectional view showing another example of the transparent member constituting the light guide member according to the present invention.

FIG. 18 is a front view of a main part showing another example of the second side surface formed on the light guide member according to the present invention.

FIG. 19 is a main part front view showing another example of the second side surface formed on the light guide member according to the present invention.

FIG. 20 is a main part front view showing another example of the second side surface formed on the light guide member according to the present invention.

FIG. 21 is a main part front view showing another example of the second side surface formed on the light guide member according to the present invention.

FIG. 22 is a front view showing another example of the light guide member and the linear light source device according to the present invention.

FIG. 23 is a front view showing another example of the light guide member and the linear light source device according to the present invention.

FIG. 24 is a front view showing another example of the light guide member and the linear light source device according to the present invention.

FIG. 25 is a front view showing another example of the light guide member and the linear light source device according to the present invention.

FIG. 26 is a front view showing another example of the light guide member and the linear light source device according to the present invention.

FIG. 27 is a main part front view showing another example of the inclined surface on which the light incident portion of the light guide member according to the present invention is formed.

FIG. 28 is a main part front view showing another example of the inclined surface on which the light incident portion of the light guide member according to the present invention is formed.

FIG. 29 is a main part front view showing another example of the inclined surface on which the light incident portion of the light guide member according to the present invention is formed.

FIG. 30 is a main part perspective view showing an example of a positional relationship among a light emitting part, a light incident part, and a light source of the light guide member according to the present invention.

FIG. 31 is a perspective view of a main part showing an example of a positional relationship among a light emitting part, a light incident part, and a light source of the light guide member according to the present invention.

FIG. 32 is a perspective view of a main part showing an example of a positional relationship among a light emitting part, a light incident part, and a light source of the light guide member according to the present invention.

FIG. 33 is an explanatory view showing an example of a conventional linear light source device.

FIG. 34 is an explanatory view showing another example of a conventional linear light source device.

[Explanation of symbols]

 1, 1A-1C Light guide member 2, 2A-2E Inclined surface 3 LED lamp (light source) 6, 6A-6E Inclined surface 10, 10a-10g Transparent member 10A First side surface 10B Second side surface 10C Third side surface 10D Fourth Side surface 10E End surface 12 Light emitting surface 13 Flat portion 14, 14A Concave portion 14a, 14b Inclined surface 15, 15A, 15B Light incident portion 17, 17A Light diffuse reflection region 41, 41A Casing 42 Image reading surface L Reading line D Document A Linear Light source device B, Ba Image reading device

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI H04N 1/107 H04N 1/04 A

Claims (24)

[Claims] 1. A plurality of outer peripheral side surfaces extending in a longitudinal direction of the transparent member are formed on an outer surface of a transparent member having a predetermined length, and a first side surface of the plurality of outer peripheral side surfaces is formed in the transparent member. A light guide member that is a light exit surface that emits light that enters and travels in the longitudinal direction to the outside of the transparent member, wherein the light incident portion for causing light to enter the transparent member is A light guide member, which is provided at a longitudinal end of one of the outer peripheral side surfaces of the transparent member. 2. The light guide member according to claim 1, wherein the light incident portion is provided at each of both longitudinal end portions of the outer peripheral side surface. 3. An inclined surface facing the light incident portion in a thickness direction or a width direction of the transparent member is formed at a longitudinal end of the transparent member.
3. The light guide member according to claim 1. 4. The light incident portion is provided on a second side surface opposite to the first side surface in the thickness direction of the transparent member, and the inclined surface is provided at a longitudinal end of the first side surface. 4. The light guide member according to claim 3, wherein the light guide member is continuously provided, and the inclined surface is inclined away from the second side surface toward a central portion in the longitudinal direction of the transparent member. 5. 5. The light incident portion is provided on a third side surface of the transparent member connected to intersect with the first side surface, and the inclined surface is provided on the third side surface with respect to the third side surface. The inclined surface is connected to the longitudinal end of the fourth side surface facing the width direction of the optical member, and the inclined surface is separated from the third side surface toward the longitudinal central portion of the transparent member. The light guide member according to claim 3, wherein the light guide member is inclined. 6. The light incident portion is provided on the first side surface, and the inclined surface is provided at a longitudinal end of a second side surface opposed to the first side surface in a thickness direction of the transparent member. The light guide member according to claim 3, wherein the light guide member is continuously provided, and the inclined surface is inclined so as to move away from the first side surface toward a central portion in the longitudinal direction of the transparent member. 7. The inclined surface is a non-light-transmitting surface.
The light guide member according to claim 3. 8. The light guide member according to claim 7, wherein the non-light-transmitting surface is formed by depositing, plating, thermally transferring, or printing a glossy material on the inclined surface. 9. The transparent member according to claim 3, wherein an end face extending in the thickness direction and the width direction of the transparent member is provided on one side of the light incident portion at one end of the inclined surface. The light guide member according to any one of the preceding claims. 10. The light guide member according to claim 3, wherein the inclined surface is a convex curved surface. 11. The light guide member according to claim 1, wherein the first side surface is a mirror-like plane. 12. The device according to claim 1, wherein a width of the first side surface is smaller than a width of a second side surface facing the first side surface in a thickness direction of the transparent member. Light guide member. 13. A second side surface opposed to the first side surface in a thickness direction of the transparent member has a plurality of concave portions,
The light guide member according to any one of claims 1 to 12, wherein these concave portions have a curved or planar inclined surface facing the light emitting surface obliquely. 14. The light-diffused reflective area for diffusely reflecting light, wherein a substantially entire surface area or a selected partial area of the second side face opposed to the first side face and the thickness direction of the transparent member is formed. 13. The light guide member according to any one of 1 to 12. 15. The light diffuse reflection region is a region where a paint that performs light scattering reflection is applied to the second side surface, a region where a tape piece that performs light scattering reflection is adhered, or the surface of the second side surface has an uneven shape. The light guide member according to claim 14, wherein the light guide member is a region having a rough surface. 16. A second side surface opposite to the first side surface in a thickness direction of the transparent member is inclined or curved so that a distance between the first side surface and the first side surface decreases as the distance from the light incident portion increases. The light guide member according to claim 1, wherein: 17. An outer surface of a transparent member having a predetermined length,
A plurality of outer peripheral side surfaces extending in the longitudinal direction of the transparent member are formed, and a first side surface of the plurality of outer peripheral side surfaces emits light that enters the transparent member and travels in the longitudinal direction to the outside of the transparent member. A light guide member serving as a light exit surface for emitting light to the transparent member, wherein an inclined surface is formed at a longitudinal end of the transparent member, and the inclined surface allows light to enter the transparent member. A light guide member, which is a light incident portion for causing the light guide member to emit light. 18. The device according to claim 18, wherein the inclined surface is a longitudinal end of a second side surface facing the first side surface in a thickness direction of the transparent member,
The light guide member according to claim 17, wherein the light guide member is connected to a longitudinal end of a third side connected in a direction intersecting with the first side or a longitudinal end of the first side. 19. A linear light source device comprising: the light guide member according to claim 1; and a light source facing a light incident portion of the light guide member. . 20. The light source according to claim 1, wherein the light source is an LED.
10. The linear light source device according to 9. 21. The linear light source device according to claim 19, wherein the light source is a white LED. 22. The light source is a three-color LE of R, G, and B.
20. The linear light source device according to claim 19, wherein D is a combination. 23. Light from a light source device is radiated to a document placed opposite to the document reading surface, and reflected light from the document on a reading line set on the document reading surface is arranged in the reading line direction. An image reading device configured to allow a plurality of light receiving elements to receive light, wherein the linear light source device according to any one of claims 19 to 22 is used as the light source device.
Image reading device. 24. The linear light source device and the light receiving element,
3. A handy scanner which is housed in a movable casing that can be gripped and is entirely configured as a handy scanner.
4. The image reading device according to 3.