JP4037888B2 - Line-shaped illumination device and image reading device using the same - Google Patents

Description

  BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a line illumination device used in an image reading apparatus such as an image scanner, a facsimile or a copying machine, and more particularly to a line illumination used in an image sensor unit that irradiates a reading surface of a document and reads reflected light. The present invention relates to an apparatus and an image reading apparatus using the same.

2. Description of the Related Art Conventionally, there are various types of image sensors used in image reading apparatuses such as image scanners, facsimiles, and copiers, such as reduction types and contact types. Among them, the contact image sensor (hereinafter abbreviated as CIS) includes an illumination device, a unity magnification optical device, a line sensor, and the like. Such CIS generally has a feature that the optical path length is shorter than that of an image sensor using a reduction optical system, and thus a device including this image sensor can be easily miniaturized. Thus CIS is because it is easily incorporated into the device, it has come to be often used in thin flatbed type image reading apparatus or the like in place of the reduction optical system. Such a line illuminating device used for CIS is required to illuminate a document surface with a required illuminance or higher so that reflected light from the document reaches the line sensor with sufficient intensity.

FIG. 4 is a cross-sectional view of a conventional contact image sensor, and shows a case where the number of the light guides 42 is one. This close contact type image sensor has a light source for irradiating an original, receives reflected light from the original 49 through a lens array 44 by a light receiving portion formed of a photoelectric conversion element (CCD), and converts it into an electric signal.

  In the figure, reference numeral 43 denotes a frame that supports the constituent members, and 44 denotes a lens array that forms an optical image of a document 49 on a line sensor 45. Reference numeral 45 denotes a line sensor arranged in a line having a plurality of light receiving portions that photoelectrically convert an optical image of the document 49 into an electric signal. Reference numeral 46 denotes a sensor substrate on which the line sensor 45 is mounted. Each of 41r, 41g, and 41b is a light source having an LED for illuminating the document 49, and is disposed on one end face of the light guide 42 that extends in the longitudinal direction. The light source unit 41 includes a light guide 42 designed to take in light emitted from the LEDs 41r, 41g, and 41b and to make the amount of illumination light substantially uniform over the length of one line of the line sensor 45. . Reference numeral 47 denotes a connector for connecting a sensor signal to an external device, and reference numeral 48 denotes a transparent glass document support table for supporting the document 49.

  The light emitted from the LED disposed on the end face of the light guide 42 is guided to the acrylic light guide 42 and is emitted to the outside from the emission surface (light emitting portion) while reflecting the inside in a complicated manner. The document 49 is illuminated. For the purpose of assisting reflection in the light guide body, titanium oxide powder or aluminum powder is disposed on the reflection part or the terminal part (opposite side of the light incident surface) of the light guide body 42 by means such as printing. preferable.

As these line-shaped illuminating devices, a line-shaped illuminating device in which a light emitting element is provided at one end (light incident portion) of an acrylic rod-shaped transparent body (light guide) is used. (For details, see Patent Document 1, Patent Document 2 and Patent Document 3)
The line-shaped illuminating devices described in these publications aim to reduce costs by arranging LEDs that are light-emitting elements only at one end of a rod-like transparent body (light guide). Furthermore, the shape of the light guide is devised so that uniform illuminance can be obtained along the longitudinal direction of the light guide, and from the light incident surface of the light guide on which light from the LED is incident toward the terminal portion. The illuminance is as uniform as possible.
Japanese Patent Registration Publication No. 2693098 JP-A-8-163320 Japanese Patent Laid-Open No. 10-241432

  However, the above conventional example has the following problems.

  First, FIG. 5A and FIG. 5B show an example of a cross-sectional shape of a conventional line illumination device described in Patent Document 3, and the problems will be described.

The arrow in the figure indicates the direction of the light beam. In FIG. 5A, a wedge-shaped groove 500 is provided between a light guide portion 501 in which light from a light incident surface enters in a substantially vertical direction of the drawing and a light exit portion 502 from which the light exits. . In this configuration, there is a relatively large amount of light 510 that returns from the light exit unit 502 to the light guide unit 501. Further, the light 511 traveling from the light guide unit 501 to the light output unit 502 is also emitted in a direction different from the predetermined direction. For this reason, these lights do not become effective illumination light. As a result, there is a problem that the illumination light quantity cannot be increased due to insufficient illumination light quantity.

In FIG. 5B, as indicated by 500 and 503, two cross sections are provided with a wedge-shaped groove . Similarly in these shapes, the reflected light 512 from the bottom surface 521 on the light guide unit 501 side enters the light output unit 502, and the light is emitted in a direction that does not contribute to illumination of the document. On the other hand, like the reflected light from the bottom surface 522 on the light exiting portion 502 side, the light returns from the light exiting portion 502 to the light guiding portion 501, and the light is not emitted and the illumination light amount of the document is reduced. was there.

  An object of the present invention is to solve such conventional problems.

  A feature of the present invention is that, in a contact image sensor unit, line illumination that increases the illuminance of illumination light emitted from a linear illumination device and makes the illuminance distribution along the longitudinal direction of the light guide more uniform. To provide an apparatus.

  Another feature of the present invention is to provide a line illuminating device that improves the rising characteristics of the illuminance of the illumination light and makes the effective reading length of the light guide longer.

In order to achieve the above object, a line illumination device according to one embodiment of the present invention has the following configuration. That is,
A light source;
A light guide unit that is made of a transparent medium and that enters the light from the light source from a light incident surface that is one end surface of the light guide unit extending in the longitudinal direction and guides the light along the longitudinal direction; In order to control the amount of light emitted from the light guide unit to the light output unit, and the light output unit having an output surface for emitting the light guided to the light guide unit in a line shape over the longitudinal direction, A light guide including first and second grooves disposed at opposing positions along the longitudinal direction of the light guide between the light guide and the light exit;
The cross section of the first groove is wedge-shaped, and the depth is changed to be deepest near the center in the longitudinal direction of the light guide part and shallow at both ends in the longitudinal direction of the light guide part. The first angle formed by the side wall surface of the light guide unit with respect to the bottom surface on the light guide unit side in the light guide body is such that the light output unit wall surface of the second groove is on the light output unit side bottom surface in the light guide body. It is larger than the 2nd angle made with respect to it.

Further, the light guide further entering-a first region depth of the second groove from the light plane along the longitudinal direction increases continuously, the light incident surface from the first region And a second region where the depth of the second groove is substantially constant until reaching the terminal portion on the opposite side of the first groove .

Furthermore, the light guide further includes a first region depth entering-from a light surface of the longitudinal direction along the second groove increases continuously, fill before following the first region and the second region is a deep Saga substantially constant said second grooves toward the end portion on the opposite side of the light plane, toward the end portion along the longitudinal direction subsequent to said second region And a third region in which the depth of the second groove continuously decreases.

  According to the present invention, not only the illuminance of the linear illumination device increases, but also the illuminance distribution becomes more uniform. In addition, since the illuminance distribution of the illumination light emitted in the vicinity of the light incident part of the light guide is uniform, the effective reading length of the light guide can be made longer, unnecessary space is reduced, and product mounting is also downsized. There are advantages you can do. In addition, even if the arrangement position of the LED with respect to the light guide is shifted, it is difficult to influence the illuminance distribution, so that the height position adjusting process in the LED mounting process can be made relatively simple.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The following embodiments do not limit the present invention according to the claims, and all combinations of features described in the present embodiments are essential to the solution means of the present invention. Not exclusively.

Light guide of the linear illumination device according to this embodiment is basically the same shape as the light guide body shown in FIG. 4, the traditional wedge shape between the light guide and the light exit portion is characterized in that cross-section in place of the grooves has a rectangular groove structure. As described above, this embodiment is characterized in that, in addition to the conventional line illumination device, a new structure for controlling the amount of emitted light is added in the vicinity of the light guide unit and / or in the vicinity of the light output unit.

[Embodiment 1]
An example of a line illumination device according to Embodiment 1 of the present invention is shown in FIG.

  FIG. 1A shows a cross-sectional view at a substantially central portion in the longitudinal direction of the light guide 100 of the line illumination device according to the first embodiment. The light guide 100 can be roughly divided into a light guide part 101 and a light exit part 102 along the longitudinal direction. An LED 120, which is a light source, is disposed in the vicinity of an end surface (hereinafter referred to as a light incident surface 110 (FIG. 1B)) on at least one side of the light guide 100. The light guide unit 101 receives light emitted from the LEDs 120 arranged near the outside of the light incident surface 110, transmits the light in the longitudinal direction of the light guide 100, and develops the light toward the light output unit 102. It has a function to do. The light exit unit 102 receives light from the light guide unit 101 and emits light in a predetermined direction from a light exit surface provided in a part of the light exit unit 102. As a result, the read target portion of the document is illuminated in a line.

In the light guide 100 shown in FIG. 1A, a groove 103 having a certain depth at the boundary between the light guide part 101 and the light output part 102 and having a rectangular cross section is formed, and further, at a position facing the groove 103. A groove 104 having a wedge-shaped cross section is provided. The groove 103 and the groove 104 serve as a light quantity adjusting valve, which is common to the conventional idea. However, in the first embodiment, the transmission of light between the light guide unit 101 and the light output unit 102 is more effectively controlled by making the cross-sectional shape of the groove 103 rectangular. Regarding the groove 104, the amount of light entering the light output unit 102 is controlled by changing the depth of the groove 104 according to the distance from the light source along the longitudinal direction of the light guide 100. Specifically, the depth of the groove 104 is deepest in the vicinity of the approximate center in the longitudinal direction of the light guide 100, and the depth is shallow at the light incident surface and the end portion. Also with respect to the groove 103, than the angle with respect to the bottom surface of the light guide portion 101 inside the light guide member 101, the angle is present What small kuna inside the light guide member 101 relative to the bottom surface of the light exit portion 102 side.

  FIG. 1B is a schematic perspective view showing the entire light guide 100.

The light guide 100 is formed of a transparent medium, the groove 103 toward the light incident surface 110 to the end portion is formed in the same shape, the groove 104 is rather shallow at both ends near the most deep Kunar so near the center Is formed.

FIG. 2 is a cross-sectional view of the light guide 100 for explaining the role of the groove 103.

In FIG. 2, compared with the conventional example shown in FIGS. 5A and 5B, the light exit surface side of the groove 103 has a wall surface having a vertical angle. Thus, the light 201 traveling directly from the light guide unit 101 to the light output unit 102 at a low angle is blocked, and the light 202 returning from the light output unit 102 to the light guide unit 101 is blocked. Thus, the first bottom surface 210 belonging to the light guide unit 101 and the second bottom surface 211 belonging to the light output unit 102 reduce the amount of light once entering the light output unit 102 back to the light guide unit 101. Since the light that enters the light output unit 102 from the light guide unit 101 is also used efficiently, the illuminance on the document can be increased compared to the conventional example.

  FIG. 3 is a diagram illustrating the illuminance distribution in the longitudinal direction of the lighting apparatus according to the present embodiment.

  In FIG. 3, the LED as the light source is arranged on the light incident surface side, that is, on the left side in FIG. 3, and the vertical axis indicates relative illumination at the illumination position of the document along the longitudinal direction of the light guide 100. It shows the amount of light. The horizontal axis represents the length from the light incident surface 110 (unit: mm).

  In FIG. 3, a line indicated by 300 indicates the illuminance characteristics in the lighting apparatus according to the present embodiment, and a line indicated by 301 indicates the illuminance characteristics by the conventional lighting apparatus having a cross section shown in FIG. 5B. . In the conventional illuminating device, the illuminance increases at a position of about 15 mm from the light incident surface 110, and then shows the maximum illuminance and gradually attenuates toward the end portion. This is presumably because a part of the light emitted from the light source (LED) directly enters the light exit part 102 in the vicinity of the light incident surface 110 and increases the amount of light near the light incident surface.

  On the other hand, in the illuminating device which concerns on Embodiment 1 of this invention, the tendency is relieved and it turns out that substantially uniform illumination intensity is obtained over the longitudinal direction of the light guide 100. FIG.

[Embodiment 2]
Here, when observing FIG. 3 which is the illuminance characteristic of the lighting apparatus according to Embodiment 1 in more detail, there is a region where the illuminance is low in the vicinity of about 15 mm from the light incident surface 110, and the same is also observed in the vicinity of about 10 mm from the end portion. It can be seen that there is a region where the illuminance falls more. This is considered to be because the direct light from the light source 120 enters almost the center of the light guide 100, so that the light diffuses in the vicinity of the light incident surface 110 and the light reaching the light exit portion 102 decreases.

  On the other hand, in the conventional lighting device, the peak of illuminance is obtained in the range of 20 to 50 mm from the light incident surface. This is considered to be caused by the addition of light that reaches the light exit unit 502 directly from the light source. On the other hand, since the illuminance is low near the light incident surface of the illuminating device, the original cannot be read near the light incident surface. Therefore, this part is a useless part of the lighting device. Similarly, there is also a portion where the illuminance is reduced in the range of several millimeters from the end portion at the end portion on the opposite side of the light incident surface. Therefore, it is required to shorten the length of the portion where the illuminance is lowered to reduce the useless portion.

  Such illuminance characteristics are slightly different for each color. Currently, many CISs use LEDs of three colors, red, green and blue. As shown in FIG. 4, these are arranged in the horizontal direction in the vicinity of the light incident surface of the light guide. For this reason, depending on the position where the LED is disposed, the LED farther from the light-emitting portion tends to deteriorate the illuminance rising characteristic. As a result, not only the illuminance uniformity in the vicinity of the light incident portion but also the chromaticity characteristics at the light exit portion have been degraded.

  In addition, since the portion where the illuminance decreases in this way is not used for reading the original, both ends of the CIS cannot be used and are wasted. Therefore, there has been a demand for the entire area to be an effective area while keeping the size of the lighting device small.

Therefore, in Embodiment 2, in order to improve the illumination intensity in the vicinity of the light incident portion, and shallow comb the depth of the groove 103 is very close to the light incident surface, it has been interrupted prior art, the direct light from the light source 120 A part of the light is taken into the light emitting unit 102 and used as illumination light. Thus, it is characterized in that a region with low illuminance near the light incident surface is reduced.

  FIG. 6 is a schematic perspective view of a light guide 100a according to Embodiment 2 of the present invention.

The light guide 100a is formed by molding an acrylic material into the shape shown in FIG. The light guide 100a has a long and narrow shape, and includes a light guide unit 101 that guides light from the light source 120 in the longitudinal direction and a light output unit 102 that emits illumination light that illuminates the document in a line shape. Is the same as in the first embodiment. Similar to the first embodiment, the groove 104 and the groove 103 shown in FIG. 6 are formed at positions where the light guide unit 101 and the light output unit 102 are separated.

The shape of the groove 103 along the longitudinal direction of the light guide 100a, the first region 601 gradually deep Kunar distance its depth to the vicinity of about 5.5mm from the light entrance surface 110, After that, it has the 2nd area | region 602 which is a shape which reaches a termination | terminus part with a fixed depth . This feature, in the region of up to about a distance of about 5.5mm from the light entrance surface 110, the depth and the depth of the groove 104 of the groove 103, the end portion from a state of substantially depth without (depth = 0) gradually deep comb toward and from the first region 601 into the second region 602, the depth of the groove 103, for example in that the constant depth according to the first above-described embodiment. As a result, more light, including direct light from the light source 120 and light from the bottom surface of the light guide unit 100 a, reaches the light output unit 102 from the light guide unit 101. In this way, a decrease in illuminance near the light incident surface 110 is compensated.

In the vicinity of the light incident surface 110, there is light that travels directly from the LED 120 to the light exit portion 102, and conventionally, this direct light has been blocked by forming a groove or the like so as not to be used as much as possible. On the other hand, in the second embodiment, on the contrary, by using the direct light from the light source 120, the illuminance in the vicinity of the light incident surface 110 was successfully increased.

In contrast, in the long distance portion of the light entrance surface 110, the depth comb depth of the groove 103, and regulates the amount of light by varying in accordance with the depth of the groove 104 in the distance. As a result, the amount of light reaching the light exiting portion 102 is adjusted to make the illuminance in the longitudinal direction of the light guide 100a uniform.

  The result that the illuminance in the vicinity of the light incident surface 110 is improved by the light guide body 100a of the second embodiment will be described with reference to FIG.

  FIG. 9 is a diagram showing the rising characteristics of illuminance in the vicinity of the light incident surface of the illumination devices according to Embodiments 1 and 2 of the present invention. In the figure, 900 indicates the result according to the first embodiment, and 901 indicates the result according to the second embodiment.

  In FIG. 9, the illuminance in the vicinity of the light incident surface is shown as a relative value, but in the second embodiment, the illuminance rises better when the distance from the light incident surface is about 4 mm than in the first embodiment. Recognize. As a result, the effective length of the light guide that can effectively irradiate the document is increased, and the length of the light guide corresponding to a document having a certain width can be relatively shortened. .

  Further, it has been found that the shape of the light guide body 100a of the second embodiment further has the following new effects.

  FIG. 10 is a diagram showing the illuminance distribution when the LED mounting positions are different in the lighting apparatus according to Embodiment 1 of the present invention.

  In the light guide 100 shown in Embodiment 1, when the arrangement position of the LED 120 arranged on the light incident surface 110 side is shifted in the vertical direction, the illuminance distribution characteristics are different in the longitudinal direction of the light guide 100. Yes. In particular, in the region close to the light incident surface 110, it has been found that the illuminance change is large even if the mounting position of the LED 120 is slightly different. Therefore, in the illuminating device of Embodiment 1, it is necessary to carefully adjust the mounting height position of the LED 120 in the manufacturing process, which is extremely complicated in the manufacturing process.

  FIG. 11 is a diagram showing the illuminance distribution when the LED mounting positions are different in the illumination device according to Embodiment 2 of the present invention.

  FIG. 11 shows the illuminance distribution characteristic in the longitudinal direction when the LED mounting position is changed. Thus, it can be seen that the illuminance distribution characteristics do not change much even if the LED mounting positions are different. Therefore, in the manufacturing process, the alignment of the LED is simplified, the variation in the illuminance distribution of the product is reduced, and the manufacturing process time can be shortened.

[Embodiment 3]
In the third embodiment, the depth of the groove 103 in the vicinity of the terminal portion in addition to the vicinity of the light incident surface 110 is changed stepwise. The details are shown in FIG.

  FIG. 7 is a schematic perspective view of the light guide 100b of the lighting apparatus according to Embodiment 3 of the present invention.

In the third embodiment, along the longitudinal direction of the light guide 100b, a first region 701 in which the groove 103 is gradually deepened from the light incident surface 110 as shown in FIG. in addition to the second realm 702 grooves 103 of a predetermined depth is formed, by the features of the third realm 703 gradually groove 103 about 6mm around from the end portion becomes shallow is provided is there. The shape of the groove 104 is the same as in the first and second embodiments.

  In addition, a reflection member made of aluminum or the like is disposed at the end portion of the light guide 100b to increase the reflection efficiency of light from the light source 120. By doing so, the light source is arranged at the end portion, and the tendency for the illuminance to decrease near the end portion is alleviated. Therefore, it is possible to reduce the portion where the illuminance decreases in the vicinity of the terminal portion. As a result, the effective length of the light guide that gives a relatively effective illuminance is increased, and the area that cannot be used due to the low illuminance can be shortened. As a result, the length of the illumination device that illuminates a document of a certain length can be shortened, and thus the width of the image reading device can be shortened accordingly.

  In the first and second embodiments described above, a reflecting member made of aluminum or the like may be disposed at the end of the light guide 100b.

[Embodiment 4]
For flatbed type image scanner is described using the illumination apparatus according to the first to the third embodiments.

FIG. 8 is a schematic perspective view of an image reading apparatus which is an application example of the image sensor according to the embodiment of the present invention. Here is an example of a flatbed type image reading apparatus using the contact type image sensor.

In FIG. 8, reference numeral 81 denotes a CIS provided with the lighting device of the present embodiment. 82 is a glass plate as a document support, 83 is a wire for operating the CIS, 84 is a drive motor for moving the wire 83 in the reading direction, and 85 is a document pressure plate.

  By driving the drive motor 84 and mechanically moving the wire 83, the CIS 81 can move in the reading direction (scanning direction) and read the image information of the document. The CIS is configured as a sensor unit in which an illuminating unit is integrated, and reflected light from an illuminated original is condensed on a photoelectric conversion element by a lens array (not shown) in the CIS, and is used as image information for each line. Is output. In this way, sheet-like image information can be read and output.

  In the image scanner equipped with the CIS unit according to the present embodiment, the length of the illumination device can be further shortened, so that the width of the image scanner can be shortened and the size of the image reading device can be further reduced. it can.

  As described above, according to the present embodiment, not only the illuminance of the line illumination device can be increased, but also the illuminance distribution becomes more uniform.

  In addition, since the illuminance distribution of the illumination light emitted in the vicinity of the light incident portion of the light guide becomes uniform, the effective reading length of the light guide can be made longer. As a result, unnecessary space is reduced and there is an advantage that the product can be miniaturized.

  Moreover, according to this Embodiment, since the influence with respect to illumination intensity distribution can be made small even if the arrangement position of LED with respect to a light guide has shifted | deviated, the attachment position adjustment in the attachment process of LED can be made comparatively simple.

  The present invention is not limited to the embodiment described above, and various changes and modifications can be made without departing from the spirit of the present invention. Therefore, the technical scope of the present invention should be specified by the following claims.

It is sectional drawing of the linear illuminating device which concerns on Embodiment 1 of this invention. It is a perspective view of the line-shaped illuminating device which concerns on Embodiment 1 of this invention. It is a figure which shows the optical effect at the time of using the linear illuminating device which concerns on Embodiment 1. FIG. It is a figure which shows the illumination intensity distribution of the longitudinal direction of the linear illuminating device by Embodiment 1 of this invention. It is a structure sectional view of the conventional contact type image sensor. It is sectional drawing of the conventional illuminating device with a wedge- shaped groove | channel . It is a figure which shows the motion of the light unpreferable of the conventional illuminating device which has a wedge- shaped groove | channel . It is a perspective view which shows the structure of the illuminating device which concerns on Embodiment 2 of this invention. It is a perspective view which shows the structure of the illuminating device which concerns on Embodiment 3 of this invention. It is a figure which shows an example of the flatbed type image reading apparatus using the illuminating device which concerns on embodiment of this invention. It is a figure which shows the rising characteristic of the illumination intensity in the light-incidence surface vicinity of the illuminating device which concerns on Embodiment 1, 2 of this invention. It is a figure which shows illuminance distribution when the attachment position of LED differs in the illuminating device which concerns on Embodiment 1 of this invention. It is a figure which shows illuminance distribution when the attachment position of LED differs in the illuminating device which concerns on Embodiment 2 of this invention.

Claims (6)

A light source;
A light guide unit that is made of a transparent medium and that enters the light from the light source from a light incident surface that is one end surface of the light guide unit extending in the longitudinal direction and guides the light along the longitudinal direction; In order to control the amount of light emitted from the light guide unit to the light output unit, and the light output unit having an output surface for emitting the light guided to the light guide unit in a line shape over the longitudinal direction, A light guide including first and second grooves disposed at opposing positions along the longitudinal direction of the light guide between the light guide and the light exit;
The cross section of the first groove is wedge-shaped, and the depth is changed to be deepest near the center in the longitudinal direction of the light guide part and shallow at both ends in the longitudinal direction of the light guide part. The first angle formed by the side wall surface of the light guide unit with respect to the bottom surface on the light guide unit side in the light guide body is such that the light output unit wall surface of the second groove is on the light output unit side bottom surface in the light guide body. A line illumination device characterized by being larger than a second angle made with respect to the line illumination device.   The light guide further includes a first region in which a depth of the second groove continuously increases along the longitudinal direction from the light incident surface, and an opposite of the light incident surface from the first region. The line-shaped illumination device according to claim 1, further comprising: a second region in which a depth of the second groove is substantially constant until reaching a terminal portion on the side. The light guide further includes a first region in which a depth of the second groove continuously increases along the longitudinal direction from the light incident surface, and the light incident surface following the first region. said second region depth of the second groove is substantially constant toward the end portion on the opposite side, up to the said terminal end along the longitudinal direction subsequent to said second region first The line illumination device according to claim 1, further comprising a third region in which the depth of the two grooves continuously decreases.   4. The light guide body according to claim 1, further comprising: a reflecting member that reflects light at a terminal portion opposite to the light incident surface. 5. Line lighting device.   5. The linear illumination device according to claim 1, wherein the light source is an LED, and the light source is disposed in proximity to the light incident surface. 6. A line illumination device according to any one of claims 1 to 5 ,
Line-shaped image forming means for irradiating the original with light emitted from the exit surface of the line-shaped illumination device and forming an image of reflected light reflected from the original;
A line sensor comprising a plurality of pixels for converting the reflected light into an electrical signal;
An image reading apparatus comprising:

Images