JP2000349955A - Serial color image sensor and image reader - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a serial color image sensor by which read speed is accelerated, banding is mitigated and the manufacture cost is reduced. SOLUTION: This color image sensor is provided with a semiconductor color sensor 9, that has a white light emitting diode 7 emitting a white light and a plurality of red light receiving sections, blue light receiving sections and green light receiving sections respectively, receives the white light emitted from the white light emitting diode 7 and reflected in a read face 23 by each light receiving section to simultaneously output a red read image signal, a blue read image signal and a green read image signal, and a rod lens array 19 that forms an image emitted from the while light emitting diode 7 and reflected in the read face 23 to each light receiving section of the semiconductor color sensor 9 as an erect and unmagnified image.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a serial type color image sensor for reading an image on a read original by moving relative to the original in a main scanning direction and a sub-scanning direction, and a serial color image sensor. The present invention relates to an image reading device provided with an image sensor.

[0002]

2. Description of the Related Art As shown in FIG. 15, a conventional serial type color image sensor has a wiring board 51, a light emitting diode array 52, a prism 53, a lens 54, and a mirror 5.
5, a lens 56, a wiring board 57, a semiconductor monochrome sensor 58, and flexible cables 59 and 60. Then, as shown in FIG. 16, the light emitting diode array 52 was provided with two green light emitting diodes 52G, two blue light emitting diodes 52B, and one red light emitting diode 52R.

In this conventional serial type color image sensor, red light emitting diodes 52 R, green light emitting diodes 52 G, and blue light emitting diodes 52 B of a light emitting diode array 52 are selectively turned on sequentially, and the light is read by a prism 53 to a reading surface 65. And the reflected light from the reading surface 65 is reduced by the lens
The path is changed, and the light is further reduced by the lens 56 and enters the light receiving surface of the semiconductor monochrome sensor 58. Accordingly, the semiconductor monochrome sensor 58 outputs a read image signal corresponding to the amount of received light to the outside via the wiring board 57, the flexible cable 60, and a connector (not shown). The driving signal of the light emitting diode array 52 is
It is supplied from outside through a connector, a flexible cable 60, a wiring board 57, and a flexible cable 59. The power and various control signals of the semiconductor monochrome sensor 58 are supplied from the outside via a connector, a flexible cable 60, and a wiring board 57.

However, in such a conventional serial type color image sensor, the reading speed is slow because the red light emitting diode 52R, the green light emitting diode 52G, and the blue light emitting diode 52B are sequentially turned on to perform reading. There were challenges. In addition, there is a problem that banding is likely to occur due to the temperature characteristics of the red light emitting diode 52R. Further, since the reduction optical system is employed, banding is likely to occur due to image distortion of the lenses 54 and 56, and high assembly accuracy is required to reduce this problem. was there. Also, since the structure is complicated and the number of parts is large,
There has been a problem that component costs and assembly costs are high.

[0005]

DISCLOSURE OF THE INVENTION The present invention has been devised in view of the above circumstances, and is a serial type color image sensor capable of increasing the reading speed, reducing banding, and reducing the manufacturing cost. Another object of the present invention is to provide an image reading apparatus.

In order to solve the above problems, the present invention provides:
The following technical measures have been taken:

According to a first aspect of the present invention, there is provided a serial type color image sensor for reading an image on a read original by moving relative to the original in both the main scanning direction and the sub-scanning direction. , One white light-emitting diode that emits white light, and a plurality of light-receiving parts for red, blue, and green, each being radiated from the white light-emitting diode and reflected by the read original. A semiconductor color sensor that simultaneously outputs a red read image signal, a blue read image signal, and a green read image signal by receiving the white light received by each light receiving section, A serial type color image sensor is provided, comprising: a lens for forming an image of the reflected white light at an equal magnification of each emissive part of the semiconductor color sensor.

According to a preferred embodiment, the semiconductor color sensor includes a red light receiving section, a blue light receiving section, and a green light receiving section which are spaced apart from each other by a predetermined distance in the sub-scanning direction. The light receiving units of the same color are arranged at a predetermined pitch in the main scanning direction.
Arranged in columns.

According to another preferred embodiment, the arrangement pitch in the sub-scanning direction of the red light receiving section, the blue light receiving section and the green light receiving section is such that the light receiving sections of the same color are arranged in the main scanning direction. It is twice the arrangement pitch.

According to another preferred embodiment, the lens is a rod lens array.

According to another preferred embodiment, the lens is two convex lens arrays arranged continuously in the optical axis direction.

According to another preferred embodiment, the white light emitting diode, the semiconductor color sensor, and the lens are incorporated in a frame, and the frame directs the white light emitted from the white light emitting diode toward the original to be read. The light guide hole for guiding is formed, and at least the wall of the frame forming the light guide hole is white.

According to another preferred embodiment, the frame is entirely white.

According to another preferred embodiment, the white light emitting diode and the semiconductor color sensor are mounted on the same wiring board.

According to another preferred embodiment, a clip-type connector is mounted on the wiring board, and the connector supplies power to the white light-emitting diode from outside the wiring board and includes a semiconductor collar. The read image signal of each color output from the sensor is supplied to the outside of the wiring board.

According to another preferred embodiment, the connecting device is a clip pin.

According to another preferred embodiment, the connector is a clip connector.

According to a second aspect of the present invention, there is provided an image reading apparatus having the serial type color image sensor according to claim 1, wherein the semiconductor color sensor includes a red light receiving section and a blue light receiving section. The light receiving sections for the same color are arranged in a row at a first predetermined pitch in the main scanning direction with the light receiving sections for green and the light receiving sections for green being mutually spaced at a predetermined interval in the sub-scanning direction. A sub-scanning direction driving unit for relatively reciprocating the serial type color image sensor at a second predetermined pitch in the sub-scanning direction, and completing one forward movement and one backward movement by the sub-scanning direction driving unit Every time, the read original and the serial type color image sensor
Main scanning direction driving means for relatively moving at predetermined pitches, and reading image signals of respective colors output from the semiconductor color sensor into a red reading image signal, a blue reading image signal and a green reading image signal of the same pixel on a reading original. Read image signal is 1
An image reading apparatus is provided, which is provided with image processing means for ignoring a read image signal of a line in which one or more of the three colors is not obtained in a combination in a set.

According to a preferred embodiment, the second predetermined pitch is equal to the first predetermined pitch, and the arrangement of the red light receiving section, the blue light receiving section and the green light receiving section in the sub-scanning direction. The pitch is twice the first predetermined pitch.

According to the present invention, a white light emitting diode having one white light emitting diode for emitting white light, a plurality of light receiving parts for red, a plurality of light receiving parts for blue and a plurality of light receiving parts for green is provided. And a semiconductor color sensor that simultaneously outputs a red read image signal, a blue read image signal, and a green read image signal by receiving white light radiated from the document and reflected by the read document by each light receiving unit. Therefore, the read image signal of red, the read image signal of blue, and the read image signal of green can be simultaneously obtained by the light emission of the white light emitting diode, and the reading speed can be increased. Further, since the white light emitting diode is used, it is possible to eliminate banding caused by the temperature characteristics of the red light emitting diode. Also,
Since the reduction optical system is not used, it is possible to favorably reduce the occurrence of banding due to image distortion of the lens without requiring high assembly accuracy. Also, since the structure is simple and the number of parts is small, the manufacturing cost can be reduced favorably.

Other features and advantages of the present invention will become more apparent from the detailed description given below with reference to the accompanying drawings.

[0022]

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 plan view of a serial type color image sensor according to the present invention, FIG. 2 is a front view thereof, FIG. 3 is a right side view thereof, FIG. 4 is a left side view thereof, and FIG. FIG. 6 is a bottom view, and FIG. FIG. 7 is a cross-sectional view taken along the line AA of FIG. 2, and a wiring board 3 is mounted on the lower surface of the frame 1 of the serial type color image sensor. A glass plate 5 is mounted on the upper surface of the frame 1. The wiring board 3 includes a white light emitting diode 7 as a light source for reading the read original, and a red light source corresponding to an image of the read original.
A semiconductor color sensor 9 for outputting green and blue read image signals is mounted, and a clip connector 11 is mounted.
Is installed.

The frame 1 has a light guide hole 13 extending from the upper surface of the wiring board 3 to the lower surface of the glass plate 5, and a through hole extending from the lower surface of the glass plate 5 to the upper surface of the wiring substrate 3 adjacent to the light guide hole 13. A hole 15 and bolt holes 17a and 17b for assembling each component of the frame 1 are formed. The light guide hole 13 has a vertical lower half and a slightly inclined upper half,
And it is slightly tapered. The upper half and the lower end of the through hole 15 are widened, and a rod lens array 19 is mounted on the upper half of the through hole 15. A frame 21 is attached to the lower end of the through hole 15. Frame 2
Numeral 1 covers the periphery of the semiconductor color sensor 9 together with the wiring board 3, and a slit 21 a is formed in the frame 21 to allow light reflected from the reading surface 23 of the read original to pass.

Each component of the frame 1 is made of a white resin, and the frame 21 is made of a black resin. As shown in FIGS. 1 and 2, the dimensions of the frame 1 in the present embodiment are 19 mm in length, 16 mm in width, and 17.2 in height.
mm. Examples of the white light emitting diode 7 include a GaN-based white light emitting diode having a phosphor layer,
A ZnSe-based white light emitting diode having no phosphor layer can be used.

FIG. 8 is a plan view of the wiring board 3, on which passive components 25 and 27 are mounted in addition to the white light emitting diode 7 and the semiconductor color sensor 9. The wiring board 3 is further provided with a plurality of terminals 29.

FIG. 9 is an enlarged plan view of the semiconductor color sensor 9. On the surface of the semiconductor color sensor 9, a red light receiving portion 31R, a green light receiving portion 31G, and a blue light receiving portion 31B are provided. Are formed in plurality. The light receiving units 31R, 31G, and 31B are arranged in a row at a predetermined pitch P along the main scanning direction, that is, the longitudinal direction of the semiconductor color sensor 9 for each color. And the light receiving unit 3
The interval between 1R and the light receiving portion 31G and the interval between the light receiving portion 31G and the light receiving portion 31B are 2P, which is twice the pitch P. Each of the light receiving sections 31R, 31G, and 31B has a structure in which the light receiving surface of the photodiode is covered with a color filter. The semiconductor color sensor 9 includes, in addition to the photodiode described above,
A field effect transistor for outputting electric charges accumulated in each photodiode, a shift register for sequentially turning on the field effect transistors, and the like are provided. In the present embodiment, the light receiving units 31R, 31G, 31B
Are provided, each of which corresponds to a reading density of 600 dpi.

Next, the operation will be described. The white light emitted from the white light emitting diode 7 is transmitted through the light guide hole 13 and the glass plate 5.
And is irradiated on the reading surface 23 of the read original. At this time, since the frame 1 is white, the white light from the white light emitting diode 7 hitting the wall surface of the frame 1 forming the light guide hole 13 is reflected almost well without being absorbed, and reaches the reading surface 23. . Therefore, the white light from the white light emitting diode 7 is guided to the reading surface 23 without any loss, and efficiently irradiates the reading surface 23 of the read document.

The white light reflected on the reading surface 23 of the read original passes through the glass plate 5 and is incident on the rod lens array 19, is condensed by the rod lens array 19, and is received by the light receiving sections 31R and 31G of the semiconductor color sensor 9. , 31B. At this time, the rod lens array 19 forms an image on the reading surface 23 of the read document on the surface of the semiconductor color sensor 9 at an erect equal magnification.

When white light is incident on the light receiving sections 31R, 31G, and 31B, the semiconductor color sensor 9 causes the red read image signal and the green read image signal corresponding to the amount of light incident on the light receiving sections 31R, 31G, and 31B. And the blue read image signal. Of course, the read image signals of each color are received by the light receiving units 31R, 31 arranged at the pitch P in the main scanning direction.
It is sequentially output for each pixel corresponding to G and 31B.

At this time, the read original is stationary. Then, the read original is fed by the pitch P in the sub-scanning direction, and the next line is read.

By repeating the above operation, a portion corresponding to the reading width of the serial type color image sensor in one page of the read document is read over all the lines.

Thereafter, the serial type color image sensor is moved in the main scanning direction by a distance corresponding to the reading width, and each line is read. At this time, the read original is sent in the reverse direction along the sub-scanning direction.

By repeating the above operation, the reading of one page of the read document is completed.

That is, as shown in FIG.
In the cycle of sec, the read image signal of each color corresponding to one line of the read width of the serial type color image sensor is output. The output of the read image signal of each color is performed in synchronization with a clock signal of a predetermined cycle.
A read image signal of each color corresponding to 304 pixels is output during the period of msec. Each time the serial type color image sensor moves in the main scanning direction, the drive voltage of the white light emitting diode 7 is adjusted and the charge accumulated in the photodiode of the semiconductor color sensor 9 is discharged for 2.5 msec.

By the way, when the read original is sent in the direction of arrow B in FIG.
When you start reading when it is received by the R, as shown in FIG. 11, in the reading in the first time t _1, and red read image signal of the first line, the green read image signal of the third line And the blue read image signal of the fifth line are output from the semiconductor color sensor 9. In reading at the next time t ₂ , the red color read image signal of the second line, the green color read image signal of the fourth line, and the blue color read image signal of the sixth line are output from the semiconductor color sensor 9. . In the reading at the next time t _3, a red read image signal of the third line, a green read image signal of the fifth line, and a blue read image signal of the seventh line are output from the semiconductor color sensor 9. . In the reading at the next time t _4, a red read image signal of the fourth line, a green read image signal of the sixth line, and a blue read image signal of the eighth line are output from the semiconductor color sensor 9. . Similarly, in the read image signals of the respective colors that are simultaneously read, the read image signal of red and the read image signal of green are shifted by two lines, and the read image signal of green and the read image signal of blue are shifted by two lines. It is out of alignment. This is because the light receiving unit 31R and the light receiving unit 31G are arranged with a shift of 2P in the sub-scanning direction, and the light receiving unit 31G and the light receiving unit 31B are arranged with a shift of 2P in the sub-scanning direction.

Also, by reversing the feeding direction of the read original,
When the document is fed in the direction opposite to the direction of arrow B in FIG. 9 and the reading is started when the image of the n-th line of the read document is received by the light receiving unit 31B, as shown in FIG. In reading at time t _n, a red read image signal of the (n−4) th line, a green read image signal of the (n−2) th line, and a blue read image signal of the nth line are output from the semiconductor color sensor 9. Is done. In reading at the next time t _{n + 1} , the red read image signal of the (n−5) th line, the green read image signal of the (n−3) th line, and the (n−1) th line
The read color image signal of the line and the semiconductor color sensor 9
Output from In the reading at the next time t _{n + 2} , the red read image signal of the (n−6) th line and the (n−4) th
The green color read image signal of the line and the blue color read image signal of the (n-2) th line are output from the semiconductor color sensor 9. In the reading at the next time t _{n + 3} , the red read image signal of the (n−7) th line, the green read image signal of the (n−5) th line, and the blue read image signal of the (n−3) th line are obtained. Output from the semiconductor color sensor 9. Similarly, in the read image signals of the respective colors that are simultaneously read, the read image signal of red and the read image signal of green are shifted by two lines, and the read image signal of green and the read image signal of blue are shifted by two lines. It is out of alignment. This is because the light receiving unit 31R and the light receiving unit 31G are arranged with a shift of 2P in the sub-scanning direction, and the light receiving unit 31G and the light receiving unit 31B are arranged with a shift of 2P in the sub-scanning direction. Also, the reason why the reading line advances from the nth line to the first line with the passage of time is that the read original is sent in the reverse direction.

Therefore, it is necessary to process the read image signals of the respective colors obtained at the same time and to rearrange the read image signals of the respective colors of red, green and blue into a set for each pixel. This process is executed using a buffer memory or the like after A / D conversion of the read image signal of each color from the semiconductor color sensor 9 by the image reading device. At this time, like the read image signals of the first to fourth lines in FIG. 11 and the read image signals of the nth to nth lines in FIG.
A read image signal of a line in which one or more of the blue colors cannot be obtained is discarded because the three colors cannot be combined. That is, it is necessary to determine the reading start position at the time of reciprocation along the sub-scanning direction in consideration of the discarded line. In FIG. 10, the read image signal of the discarded line is displayed as a dummy (Dummy).

As described above, since one white light emitting diode 7 is used as a light source, the manufacturing cost can be reduced by reducing the number of parts as compared with the case of using red, green and blue light emitting diodes. Can be. Moreover, there is no problem caused by the combination of the individual differences in the emission wavelength of the light emitting diodes of each color. Furthermore, banding due to the temperature characteristics of the red light emitting diode does not occur.

Further, since the semiconductor color sensor 9 which simultaneously outputs the red read image signal, the blue read image signal, and the green read image signal is used, the reading is made in comparison with the case where a monochrome color sensor is used. Speed can be increased.

Further, since the erecting equal-magnification type rod lens array 19 is used for the imaging optical system, banding can be reduced as compared with the case where a reduction optical system is employed. Moreover,
Easy assembly.

Further, since the read original is reciprocated in the sub-scanning direction to perform bidirectional reading, the reading speed can be increased as compared with the case where reading is performed in only one direction.

Further, since the white frame 1 is used, the white wall from which the light guide holes 13 are formed is white, so that the white light from the white light emitting diode 7 can be efficiently guided to the reading surface 23.

Further, since the white light emitting diode 7 and the semiconductor color sensor 9 are mounted on the same wiring board 3, the structure can be simplified and the assembly can be performed easily.

In the above embodiment, the rod lens array 19 is used as the lens of the imaging optical system.
As shown in FIG. 13, two convex lens arrays 35a and 35b may be used instead of the rod lens array 19. The convex lens array 35a and the convex lens array 35b are arranged such that their optical axes coincide with each other. In this case, since the expensive rod lens array 19 is not used, component costs can be reduced.

In the above-described embodiment, the clip connector 11 is mounted on the wiring board 3, but a clip pin 37 may be used instead of the clip connector 11, as shown in FIG. In this way, FPC and FF
C can be soldered, and the cost can be reduced.

In the above embodiment, the light receiving section 3
1R, 31G, 31B, the distance between the light receiving unit 3 of the same color
1R, the light receiving portion 31G, or the light receiving portion 31B is set to be twice as large as the pitch P.
This is because the manufacture of the semiconductor color sensor 9 is easier than doubled, and if the manufacture is possible, the light receiving sections 31R, 31R
The interval between G and 31B may be set to one time of the pitch P. Of course, the interval between the light receiving units 31R, 31G, and 31B may be set to three times or more the pitch P.

In the above embodiment, the frame 1 itself is made of a white material, but only the wall surface of the frame 1 where the light guide holes 13 are formed may be white.

In the above embodiment, the read original is reciprocated in the sub-scanning direction. However, the serial type color image sensor may be reciprocated in the sub-scanning direction. Good. Or,
The read document and the serial type color image sensor may be configured to reciprocate along the sub-scanning direction and in directions opposite to each other.

In the above embodiment, the serial type color image sensor is configured to move in the main scanning direction. However, the original may be configured to move in the main scanning direction. Alternatively, the read document and the serial type color image sensor may be configured to move in opposite directions along the main scanning direction.

In the above embodiment, the semiconductor color sensor 9 having a photodiode as the light receiving element is used, but a semiconductor color sensor having a photo transistor as the light receiving element may be used.

Further, the color image sensor and the image reading device of the present invention can be used not only for an image scanner but also for a digital copier, an ink jet printer or a word processor having a complex function.

[Brief description of the drawings]

FIG. 1 is a plan view of a serial type color image sensor according to the present invention.

FIG. 2 is a front view of the serial type color image sensor according to the present invention.

FIG. 3 is a right side view of the serial type color image sensor according to the present invention.

FIG. 4 is a left side view of the serial type color image sensor according to the present invention.

FIG. 5 is a bottom view of the serial type color image sensor according to the present invention.

FIG. 6 is a rear view of the serial type color image sensor according to the present invention.

FIG. 7 is a sectional view taken along line AA of FIG. 2;

FIG. 8 is an enlarged plan view of a wiring board.

FIG. 9 is a partially enlarged plan view of the semiconductor color sensor.

FIG. 10 is an explanatory diagram of operation timing of the semiconductor color sensor.

FIG. 11 is an explanatory diagram of lines that are simultaneously read by light receiving units of each color by a relative movement in a forward direction along a sub-scanning direction.

FIG. 12 is an explanatory diagram of lines that are simultaneously read by light receiving units of each color by relative movement in the reverse direction along the sub-scanning direction.

FIG. 13 is a sectional view of a serial type color image sensor according to another embodiment of the present invention.

FIG. 14 is a sectional view of a serial type color image sensor according to still another embodiment of the present invention.

FIG. 15 is a schematic configuration diagram of a conventional serial type color image sensor.

FIG. 16 is a plan view of a semiconductor sensor provided in a conventional serial type color image sensor.

[Explanation of symbols]

 Reference Signs List 1 frame 3 wiring board 5 glass plate 7 white light emitting diode 9 semiconductor color sensor 11 clip connector 13 light guide hole 15 through hole 17a, 17b bolt hole 19 rod lens array 21 frame 21a slit 23 reading surface 27 terminal 31R light receiving unit 31G light receiving Section 31B Light receiving section 35a, 35b Convex lens array 37 Clip pin

Claims (13)

[Claims] 1. A serial type color image sensor for reading an image on a read original by relatively moving in a main scanning direction and a sub-scanning direction with respect to the original to be read. A plurality of light receiving sections for red, a blue light receiving section, and a green light receiving section, each of which emits white light radiated from the white light emitting diode and reflected by the read original document. A semiconductor color sensor that simultaneously outputs a red read image signal, a blue read image signal, and a green read image signal by receiving light at a light receiving unit; and white light emitted from the white light emitting diode and reflected by the read document. A serial type color image sensor, comprising: a lens for forming an image at an equal magnification of an erect light on each of the light receiving portions of the semiconductor color sensor. 2. The semiconductor color sensor according to claim 1, wherein the light receiving section for red, the light receiving section for blue, and the light receiving section for green are separated from each other by a predetermined distance in a sub-scanning direction. 2. The serial type color image sensor according to claim 1, wherein the light receiving units are arranged in a line at a predetermined pitch in the main scanning direction. 3. The arrangement pitch of the red light receiving unit, the blue light receiving unit, and the green light receiving unit in the sub-scanning direction is two times the arrangement pitch of the light receiving units of the same color in the main scanning direction. 3. The serial type color image sensor according to claim 2, wherein the number is double. 4. The serial type color image sensor according to claim 1, wherein said lens is a rod lens array. 5. The lens according to claim 1, wherein the lenses are two convex lens arrays arranged continuously in an optical axis direction.
A serial type color image sensor according to any one of the above. 6. The white light-emitting diode, the semiconductor color sensor, and the lens are incorporated in a frame, and the frame guides white light emitted from the white light-emitting diode toward the read original. The serial color image sensor according to claim 1, wherein a light hole is formed, and at least a wall surface of the frame forming the light guide hole is white. 7. The serial type color image sensor according to claim 6, wherein said frame is entirely white. 8. The serial type color image sensor according to claim 1, wherein said white light emitting diode and said semiconductor color sensor are mounted on the same wiring board. 9. A clip type connector is mounted on the wiring board, and the connector supplies power to the white light emitting diode from outside the wiring board and outputs power from the semiconductor color sensor. 9. The serial type color image sensor according to claim 8, wherein the read image signals of the respective colors are supplied to the outside of the wiring board. 10. The connecting device is a clip pin.
A serial type color image sensor according to claim 9. 11. The serial type color image sensor according to claim 9, wherein the connection tool is a clip connector. 12. An image reading apparatus having the serial type color image sensor according to claim 1, wherein the semiconductor color sensor includes the red light receiving unit, the blue light receiving unit, and the green light receiving unit. And light receiving sections of the same color are arranged in a line at a first predetermined pitch in the main scanning direction, with the sections being spaced from each other by a predetermined distance in the sub-scanning direction. Sub-scanning direction driving means for relatively reciprocating the image sensor at a second predetermined pitch in the sub-scanning direction; and completing one forward movement and one return movement by the sub-scanning direction driving means. Main scanning direction driving means for relatively moving the read document and the serial type color image sensor at a third predetermined pitch in the main scanning direction at each time; and for each color output from the semiconductor color sensor. Preparative image signal, combined as a red read image signals and the blue of the read image signal and a green read image signal of the same pixel on the read document is set, any of the three colors 1
An image reading apparatus comprising: an image processing unit that ignores a read image signal of a line that cannot obtain more than a color. 13. The second predetermined pitch is equal to the first predetermined pitch, and the arrangement pitch of the red light receiving unit, the blue light receiving unit, and the green light receiving unit in the sub-scanning direction. Is twice as large as the first predetermined pitch.
3. The image reading device according to 2.