JP3073029B2 - Image reading method and apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image reading apparatus, such as an image reader or a facsimile, for performing shading correction of image data obtained by reading a document based on reference data obtained by reading an image reference section. Related to the device.

[0002]

2. Description of the Related Art In an image reading apparatus such as an image reader or a facsimile, a document is irradiated with light and the reflected light is converted into an electric signal by a photoelectric conversion element.

In this image reading apparatus, it is necessary to perform shading correction on an image signal in response to a change in the amount of light of a light source.

The shading correction is performed by reading an image reference portion such as a white board and inputting reference data, then reading an image of a document and inputting image data, and correcting the image data based on the reference data. .

In Japanese Patent Application Laid-Open No. 63-78666, a reference white plate is provided at a standby position, a reference black level is detected with the light source turned off, and then the light source is turned on to stabilize the light amount of the light source. After waiting for a certain time, the reference white level is detected, and then the image of the document set on the document setting surface is read.

[0006]

An image reading apparatus in which a standby position and a white plate are different from each other, that is, a standby position is provided at one end of a document setting surface and a white plate is provided at the other end. When applied to an image reading device, the reading unit moves from the standby position to the white plate, detects the black level, and then turns on the light source for a predetermined time to stabilize the light amount, and then detects the white level. Therefore, it takes a long time from when the reading unit starts moving from the standby position to when the reading unit starts reading the image.

According to the present invention, even when the image reading is started after the reading unit is moved from the first position, which is the standby position, to the second position provided with the image reference unit, the image reading is started early. It aims at obtaining a reading device.

[0008]

[Means for Solving the Problems] (1) The reading section is the first
When moving from the position to the second position, the light source is turned on to a predetermined position, then turned off and moved to the second position,
With the light source turned off, the photoelectric conversion element reads the image reference section, and then turns on the light source, and after a predetermined time, causes the photoelectric conversion element to read the image reference section.
When moving from the position to the first position, the photoelectric conversion element reads the image of the document while the light source is turned on.

(2) When the reading unit moves from the first position to the second position, after the light source is turned on to a predetermined position,
After turning off the light and moving it to the second position and turning on the light source for a predetermined time, the photoelectric conversion element reads the image reference portion,
After that, the light source is turned off, and after a predetermined time, the photoelectric conversion element reads the image reference unit. When the reading unit moves from the second position to the first position, the light source is turned on for a predetermined time, and then the photoelectric conversion element is read. Scan the original image.

(3) When the reading unit moves from the first position to the second position, the light source is turned on from a predetermined position,
After the light source is turned off for a predetermined time at the position, the photoelectric conversion element reads the image reference portion with the light source turned off, and then the light source is turned on and the photoelectric conversion element reads the image reference portion after a predetermined time. And the reading unit moves from the second position to the first position.
When moving to the position, the photoelectric conversion element reads the image of the document while the light source is turned on.

(4) When the reading unit moves from the first position to the second position, the light source is turned on from a predetermined position,
In the state where the light source is turned on at the position, the photoelectric conversion element reads the image reference portion, and then the light source is turned off, and after a predetermined time, the photoelectric conversion element reads the image reference portion. When moving to the first position, the light source is turned on for a predetermined time, and then the photoelectric conversion element is caused to read the image of the document.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. <Configuration> FIGS. 1 and 2 show an image reading apparatus 10 according to this embodiment.
1, the image reading apparatus 101 is connected to a personal computer or a word processor by a cable (not shown), is placed on a document, reads an image of the document, and transfers the image to a personal computer or the like. The outer shape is covered by a lower cover (lower casing) 102 and an upper cover (upper casing) 103.

The lower cover 102 is provided with a reading window 104 formed of a translucent member such as glass or an acrylic plate. A reading window 104 is provided on the upper cover 103.
Viewing window 105 for checking the reading area of the document under
And a grip (handle) 106 for gripping when the image reading apparatus 101 is moved or carried. The viewing window 105 is formed of the same light-transmitting member as the reading window 104. Image reading device 10 having such a shape
A reading unit 107 that reads an image while moving between the reading window 104 and the viewing window 105 along the reading window 104 is provided in the unit 1.

As shown in FIG. 3, a reading unit 107 includes a light source 108 such as a fluorescent lamp and mirrors 109, 110, 111,
112, lens 113, photoelectric conversion element such as CCD
Image sensor 114 and the image sensor 1
A circuit board 144 to which the light-receiving device 14 is attached is provided, and is covered with a cover so that external light does not enter. Note that the mirrors 110 and 111 are replaced with the lens 113 and the image sensor 11.
4, the position of the lens 113 can be adjusted from the hole 115 provided above the reading unit 107.

An indicator 116 is formed inside the reading window 104 by silk printing or the like as shown in FIG. The index portion 116 includes a portion 116A indicating a reading start position in the sub-scanning direction, a portion 116B indicating a reading range in the main scanning direction, and a portion 11 indicating a reading end position.
6C is formed in a U-shape. Note that the index portion 116C at the reading end position does not enter the reading range but protrudes out of the reading range. In the reading window 104, a white reference surface 117 for performing shading correction is formed by silk printing or pasting a white seal. On both left and right sides of the reading unit 107, as shown in FIG. One support member 118 is mounted on the guide rail 120 via a sliding sheet member. A guide rod 121 is provided on the other support member 119.
Are slidably inserted.

A wire 123 is connected to the connecting portion 122 by the spring 12.
4 are connected. The wire 123 is wound around a pair of pulleys 125 and 126. The one pulley 125 is driven by a pulse motor 131 via gears 127, 128, 129, and 130. That is, the pulley 125 is rotated by the forward / reverse rotation of the pulse motor 131, and the reading unit 107 reciprocates between the standby position and the reading start position via the wire 123 wound around the pulley 125. . The pulley 126 is attached at an angle. Wire 12
3 is a pulley 125, 12 by a tension pulley 132.
It is supported between six. Further, the reading unit 107 is provided with a protruding piece 133, and further provided with a sensor 134 for detecting that the reading unit 107 has moved to the reading standby position when the end of the protruding piece 133 contacts.

The grip 106 is provided with a finger recess 143 into which a finger enters the viewing window 105 side. A housing 146 is provided inside the grip 106, and the first and second housings 146 are provided.
The circuit boards (control boards) 135, 136 of the support member 137,
A third circuit board 139 which is supported and accommodated by 138 and accommodates a power supply circuit and the like is provided therebelow. The circuit boards 135 and 136 control the reading unit 107 and the pulse motor 131 and exchange signals with a personal computer or the like. The first circuit board 135 and the second circuit board 136 are connected to the connector 1
40 and 141 form a predetermined space and are separated from each other. When the reading unit 107 is at the standby position, the first and second circuit boards 135 and 136
7 is provided. The reading unit 107 and the first circuit board 135 are electrically connected by a flat cable 142 bent into a plurality of pieces as shown in FIG.

<Operation> The operation of the apparatus thus constructed will be described with reference to FIG. First, when the power of the image reading apparatus 101 is turned on by turning on the power of the personal computer and turning on the RS-232C, the reading unit 107 turns on the first position, for example, the sensor 134 by driving the pulse motor 131. Third
At the same time as moving to the standby position P1 in the figure, the light source 108 is turned on in step S1 in FIG.

A predetermined time after the light source 108 is turned on
If reading is not started (for example, three minutes), the light source 10
8 turns off automatically to save power. That is, step S
It is determined in step 2 whether reading has been started, and if so, it is determined in step S3 whether or not the light source 108 has been turned off. If the light source 108 is not turned off, step S4
It is determined whether a predetermined time, for example, three minutes, has elapsed since the lighting, and if it has elapsed, the light source 108 is turned off in step S5.

While the light source 108 is on, the original 6
To read the image above, the grip 106
And place it on the original to be scanned. Then, the reading window 104 is read from the viewing window 105.
, The image reading device 101 is moved so that the image to be read enters the index unit 116. When the reading area is confirmed, a reading start key or a switch provided on a personal computer (not shown) is operated. If it is determined in step S2 that the reading has been started, it is checked in step S6 whether the light source 108 is on. If not, the light source 108 is turned on in step S7. Then, in step S8, the reading unit 107 is moved to a second position, for example, the white reference reading position P2 by the rotation of the pulse motor 131. The light source 108 is turned off during the movement.

In this type of image reading apparatus 101, the same level of photoelectric conversion output can be obtained for each pixel in the main scanning direction even if the original density is the same, due to variations in the brightness of the light source 108 in the main scanning direction. Often not. Therefore, a variation in the photoelectric conversion output in the main scanning direction, that is, a white reference image having a white density is read in order to correct shading, and a variation in the photoelectric conversion output in the main scanning direction is detected in advance. The process of correcting the photoelectric conversion output actually read is performed based on the data of the variation that has been set. However, in the image reading apparatus of this embodiment, the white reference image is provided not inside the reading window 104 but outside the reading window 104. . Therefore, when starting reading,
First, the reading unit 107 is moved to the white reference reading position P2 to read the white reference surface 117, the white reference surface 117 is read at this position P2, and the photoelectric conversion output is sent to the outside. In this case, the black level is read with the light source 108 turned off, then the light source is turned on and the white level is read after 4 to 5 seconds have elapsed.

That is, the reading unit 107 is connected to the white reference surface 117.
In a state where the light source is turned off at a position facing the above, sampling of the reference black is performed in step S9. Then, the light source 108 is turned on in step S10, and it is checked in step S11 whether the light source 108 is turned on for a predetermined time or more.
Performs sampling of the reference white.

Next, in step S13, the reading unit 107
Is moved to the reading start position P3 by the reverse rotation of the pulse motor 131, and is moved from this position P3 toward the reading end position P4 at a predetermined speed. That is, reading of the document image in the sub-scanning direction is started. At this time, while moving one line in the sub-scanning direction, the reading unit 107 forms an image of the reflected light reflected from the surface of the document on the image sensor 114 one pixel at a time in the main scanning direction. As an image signal.

At step S14, it is determined whether the reading is completed. When the pulse motor 131 reaches a predetermined number of pulses after the reverse rotation of the pulse motor 131, the light source 108 of the reading unit 107
Reaches the reading end position P4, the reading ends, and the light source 108 is turned off in step S15. When the reading unit 107 further moves and the end of the protruding piece 133 provided on the reading unit 107 abuts on the sensor 134,
The sensor 134 is turned on, and the ON signal is input to a control unit (not shown) as a signal indicating that the reading unit 107 has reached the standby position P1. Therefore, the control unit stops the pulse motor 131, and waits for the next document reading operation in this state.

<Effects of Embodiment> (1) Reading Unit 107
From the standby position P1 (first position) to the white reference reading position P
2 (second position), since the light source 108 is turned on halfway and then turned off, the light source 108 is turned on until the reading unit 107 moves from the standby position P1 to the white reference reading position P2. Warm-up can be performed to some extent. Then, the reading unit 107 is moved to the white reference surface 117 with the light source 108 turned off, and the image sensor 1 is turned on with the light source 108 turned off.
14 was made to read the white reference surface 117,
The light source 10 of the reading unit 107 moved to the white reference surface 117
Reference numeral 8 indicates that the afterglow due to the previous warm-up is reduced, and the reference black can be sampled without waiting for the afterglow to be reduced after the reading unit 107 moves to the white reference surface 117. Thereafter, the light source 108 is turned on, and after a predetermined time, the image sensor 114 causes the white reference surface 11 to be displayed.
7, since the light source 108 warms up first, the time from turning on the light source 108 to reading the white reference surface 117 can be reduced. Therefore, even if the reading unit 107 moves from the standby position P1 to the white reference plane 117 through the reading window 104 and starts reading a document, the image reading apparatus 101 having a short time until the start of reading can be obtained. .

(2) Since the standby position P1 of the reading unit 107 is provided on the grip 106 side, the reading unit 107 normally operates at the standby position P before the reading unit 107 starts moving.
Because it is on one side, it is easy to balance and hold.

(3) Since the reading end position of the reading unit 107 is provided on the grip 106 side, when the image reading apparatus 101 is carried after the reading is completed, the reading unit 106 is located close to the grip 106. The grip 10 is on the viewing window 105 side of 103
Even if it protrudes greatly from 6, the downward load is grip 1
It is applied to the side near 06, so that the burden on the arm can be reduced and it is easy to hold.

[Modifications] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and for example, the following modifications are possible. (1) In the above embodiment, an image reading apparatus having a reading window and a viewing window has been described. However, an original is set on an original setting surface formed of glass or the like, and this original is held down by an openable and closable original holder. The present invention is also applicable to an image reading apparatus that reads an image of a document on a document setting surface by a reading unit that reciprocates below the surface.

(2) When reading is completed, the reading unit 10
Even if 7 returns to the standby position, the light source 108 may be turned on to stand by.

(3) When the reading unit 107 moves from the standby position P1 to the white reference reading position P2, the light source 108 is turned on to a predetermined position, then turned off and the white reference surface 117 is turned off.
After the light source 108 is turned on for a predetermined time, the image sensor 114 reads the white reference surface 117, and then the light source 108 is turned off, and after a predetermined time, the image sensor 114 reads the white reference surface 117 to read. When the unit 107 moves from the white reference reading position P2 to the standby position P1, the image sensor 114 may read an image of a document after the light source 108 is turned on for a predetermined time. When the reading unit 107 moves from the standby position P1 to the white reference reading position P2, the light source 108 may be turned on at the standby position P1, or may be turned on after moving the reading unit 107 by a predetermined amount. Also, the light source 108
May flash.

(4) When the reading unit 107 moves from the standby position P1 to the white reference reading position P2, the light source 108 is turned on from a predetermined position, and the light source 108 is turned off at the white reference reading position P2 for a predetermined time. When the image sensor 114 is turned off, the image sensor 114 reads the white reference plane 117, and then the light source 108 is turned on, and after a predetermined time, the image sensor 114 reads the white reference plane 117.
When the reading unit 107 moves from the white reference reading position P2 to the standby position P1, the image sensor 114 may read an image of a document while the light source 108 is turned on. When the reading unit 107 moves from the standby position P1 to the white reference reading position P2, the light source 108 may be turned on at the standby position P1, or may be turned on after the reading unit 107 has moved a predetermined amount.

(5) When the reading unit 107 moves from the standby position P1 to the white reference reading position P2, the light source 108 is turned on from a predetermined position, and the image sensor 114 is turned on at the white reference reading position P2. Then, the white reference plane 117 is read, and then the light source 108 is turned off.
7, when the reading unit 107 moves from the white reference reading position P2 to the standby position P1, the light source 108 may be turned on for a predetermined time, and then the image sensor 114 may read the image of the document.

[0031]

In summary, the present invention has the following advantages. (1) When the reading unit moves from the first position to the second position, the light source is turned on after turning on the light source to the predetermined position, so that the reading unit moves from the first position to the second position. The light source is warmed up to the predetermined position, and the light source can be warmed up to some extent. Then, the reading unit is moved to the second position with the light source turned off, and the photoelectric conversion element reads the image reference unit with the light source turned off. The light source has less afterglow due to the warm-up, and can sample the reference black without waiting for the afterglow to decrease after the reading unit moves to the image reference unit. After that, the light source was turned on, and after a predetermined time, the photoelectric conversion element was made to read the image reference portion.Because the light source warmed up first, the light source was turned on and then the image reference portion was read. Time can be shortened. Therefore,
Even if the reading unit moves from the first position to the image reference unit and starts reading the document, it is possible to obtain an image reading device having a short time until the start of reading.

(2) When the reading unit moves from the first position to the second position, the light source is turned on to a predetermined position to warm the light source to a certain extent, then turned off and moved to the second position. Therefore, after the light source is turned on for a predetermined time at the second position, when the photoelectric conversion element reads the image reference portion, the second
The time required for turning on the light source again at the position and reading the image reference portion can be shortened. After that, the light source is turned off, and after a predetermined time, the photoelectric conversion element reads the image reference unit. When the reading unit moves from the second position to the first position, the light source is turned on for a predetermined time, and then the photoelectric conversion element is read. Since the image of the document is read, the light source is turned on at least twice before starting to read the image of the document, and after the photoelectric conversion element reads the image reference plane with the light source turned off, The time during which the light source is turned on until the reading of the document is started can be shortened.

(3) When the reading unit moves from the first position to the second position, the light source is turned on from the predetermined position. Therefore, while the reading unit moves from the predetermined position to the second position, the light source is turned on. It can be warmed and the light source can be warmed up to some extent. Then, after the light source is turned off at the second position for a predetermined time to eliminate the afterglow, the photoelectric conversion element reads the image reference portion in a state where the light source is turned off. The conversion element reads the image reference section, and when the reading section moves from the second position to the first position, the photoelectric conversion element reads the image of the document while the light source is turned on. The light source is turned on at least once before the light is turned on and the image reference portion is read, and the waiting time until the light source is turned on and the image reference portion is read can be shortened.

(4) When the reading unit moves from the first position to the second position, the light source is turned on from a predetermined position,
In the state where the light source is turned on at the position of, the photoelectric conversion element is caused to read the image reference section, so that the reading section
The light source is turned on before reaching the position, and the image reference portion can be read at the second position with a short waiting time. After that, the light source is turned off, and after a predetermined time, the photoelectric conversion element reads the image reference section.
When moving from the position to the first position, the light source is turned on for a predetermined time and then the photoelectric conversion element is caused to read the image of the document. Therefore, at least one light source is required before the reading of the image of the document is started. After the light source is turned on and the photoelectric conversion element reads the image reference surface in a state where the light source is turned off, the time during which the light source is turned on until reading of a document is started can be shortened.

[Brief description of the drawings]

FIG. 1 is a view showing one embodiment of the present invention, and is a perspective view seen from obliquely above.

FIG. 2 is a perspective view seen from obliquely below.

FIG. 3 is a sectional view taken along line AA of FIG. 1 showing an internal structure.

FIG. 4 is a sectional view taken along line BB of FIG. 3 showing an internal structure.

FIG. 5 is a sectional view taken along the line CC of FIG. 4 showing the internal structure.

FIG. 6 is a diagram showing a structure of a reading window.

FIG. 7 is a flowchart illustrating an operation.

[Explanation of symbols]

 101 image reading device 104 reading window 105 viewing window 106 grip 107 reading unit 108 light source 114 image sensor 117 white reference surface

Claims (11)

(57) [Claims] 1. A reading unit having a light source for irradiating a document with light and a photoelectric conversion element for reading an image of the document illuminated by the light source moves at least between a first position and a second position. Arbitrarily, based on the reference data obtained by reading the image reference unit provided at the second position by the photoelectric conversion element, the reading unit may set the first position and the second position based on the reference data.
In the image reading method in which the photoelectric conversion element performs shading correction on the image data obtained by reading the image of the original when moving between the first position and the second position,
When moving from the position to the second position, the light source is turned on to a predetermined position, then turned off and moved to the second position, and the light source is turned off. Causing the photoelectric conversion element to read the image reference portion after a predetermined period of time after the image reference portion is read and the light source is turned on, and when the reading portion moves from the second position to the first position. And an image reading method in which the photoelectric conversion element reads an image of a document while the light source is turned on. 2. A reading unit having a light source for irradiating a document with light and a photoelectric conversion element for reading an image of the document illuminated by the light source moves at least between a first position and a second position. Arbitrarily, based on the reference data obtained by reading the image reference unit provided at the second position by the photoelectric conversion element, the reading unit may set the first position and the second position based on the reference data.
In the image reading method in which the photoelectric conversion element performs shading correction on the image data obtained by reading the image of the original when moving between the first position and the second position,
When moving from the position to the second position, the light source is turned on to a predetermined position, then turned off and moved to the second position, and the light source is turned on for a predetermined time. After that, the light source is turned off, and after a predetermined time, the photoelectric conversion element is made to read the image reference portion.
An image reading method for causing the photoelectric conversion element to read an image of a document after the light source is turned on for a predetermined time when moving from the position to the first position. 3. A reading unit having a light source for irradiating light on a document and a photoelectric conversion element for reading an image of the document illuminated by the light source moves between at least a first position and a second position. Arbitrarily, based on the reference data obtained by reading the image reference unit provided at the second position by the photoelectric conversion element, the reading unit may set the first position and the second position based on the reference data.
In the image reading method in which the photoelectric conversion element performs shading correction on the image data obtained by reading the image of the original when moving between the first position and the second position,
When moving from the position to the second position, the light source is turned on from a predetermined position, the light source is turned off at the second position for a predetermined time, and then the photoelectric conversion element is turned off with the light source turned off. After that, the light source is turned on, and after a predetermined time, the photoelectric conversion element is made to read the image reference portion.
An image reading method for causing the photoelectric conversion element to read an image of a document while the light source is turned on when moving from the position to the first position. 4. A reading unit having a light source for irradiating light on a document and a photoelectric conversion element for reading an image of the document illuminated by the light source moves between at least a first position and a second position. Arbitrarily, based on the reference data obtained by reading the image reference unit provided at the second position by the photoelectric conversion element, the reading unit may set the first position and the second position based on the reference data.
In the image reading method in which the photoelectric conversion element performs shading correction on the image data obtained by reading the image of the original when moving between the first position and the second position,
When moving from the position to the second position, the light source is turned on from a predetermined position, and the photoelectric conversion element reads the image reference unit in a state where the light source is turned on at the second position. Turning off the light source, causing the photoelectric conversion element to read the image reference unit after a predetermined time after turning on the light source, and turning on the light source for a predetermined time when the reading unit moves from the second position to the first position. An image reading method for causing the photoelectric conversion element to read an image of a document after the reading. 5. A casing having a reading window facing the document, a light source for irradiating the document with light, and a photoelectric conversion element for reading an image of the document illuminated by the light source. A reading unit that reads an image, and a drive mechanism that reciprocates the reading unit at least between a first position and a second position along the reading window, wherein the first position and the second When the reading unit moves between the first position and the second position based on reference data obtained by reading the image reference unit provided between the first and second positions by the photoelectric conversion element, In an image reading device in which a conversion element performs shading correction on image data obtained by reading an image of a document, the image reference unit is provided at the second position, and the reading unit is configured to read the first image. When moving from the position to the second position, the light source is turned on to a predetermined position, then turned off, and the light source is turned on a predetermined time after the reading unit moves to the second position, A light source control device that continuously turns on the light source when the reading unit moves from the second position to the first position; and a photoelectric conversion device in a state where the light source is turned off at the second position. Causing the device to read the image reference portion, and then causing the photoelectric conversion device to read the image reference portion after the light source is turned on for a predetermined time, and moving the reading portion from the second position to the first position. A reading control device for causing the photoelectric conversion element to read an image of a document when reading. 6. A casing having a reading window facing the document, a light source for irradiating the document with light, and a photoelectric conversion element for reading an image of the document illuminated with the light from the light source. A reading unit that reads an image, and a drive mechanism that reciprocates the reading unit at least between a first position and a second position along the reading window, wherein the first position and the second When the reading unit moves between the first position and the second position based on reference data obtained by reading the image reference unit provided between the first and second positions by the photoelectric conversion element, In an image reading device in which a conversion element performs shading correction on image data obtained by reading an image of a document, the image reference unit is provided at the second position, and the reading unit is configured to read the first image. When moving from the position to the second position, the light source is turned on to a predetermined position, then turned off, and when the reading unit moves to the second position, the light source is turned on for a predetermined time. A light source is turned off for a predetermined time, and then, when the reading unit moves from the second position to the first position, a light source control device for turning on the light source, and the light source is turned on at the second position. In a state where the photoelectric conversion element reads the image reference section, and in a state where the light source is turned off at the second position, the photoelectric conversion element reads the image reference section. An image reading device comprising: a reading control device that causes the photoelectric conversion element to read an image of a document after the light source is turned on for a predetermined time when moving from the second position to the first position. 7. A casing having a reading window facing the document, a light source for irradiating the document with light, and a photoelectric conversion element for reading an image of the document illuminated by the light source. A reading unit that reads an image, and a drive mechanism that reciprocates the reading unit at least between a first position and a second position along the reading window, wherein the first position and the second When the reading unit moves between the first position and the second position based on reference data obtained by reading the image reference unit provided between the first and second positions by the photoelectric conversion element, In an image reading device in which a conversion element performs shading correction on image data obtained by reading an image of a document, the image reference unit is provided at the second position, and the reading unit is configured to read the first image. When moving from the position to the second position, the light source is turned on from a predetermined position, the light source is turned off at the second position for a predetermined time, and then the light source is turned on. A light source control device for continuously turning on the light source when moving from the position to the first position; and reading the image reference portion by the photoelectric conversion element in a state where the light source is turned off at the second position. Let
In the lighting state after the light source has been turned off for a predetermined time, the photoelectric conversion element reads the image reference unit, and when the reading unit moves from the second position to the first position, the photoelectric conversion element An image reading device comprising: a reading control device that reads an image of a document. 8. A casing having a reading window facing the document, a light source for irradiating the document with light, and a photoelectric conversion element for reading an image of the document illuminated by the light source. A reading unit that reads an image, and a drive mechanism that reciprocates the reading unit at least between a first position and a second position along the reading window, wherein the first position and the second When the reading unit moves between the first position and the second position based on reference data obtained by reading the image reference unit provided between the first and second positions by the photoelectric conversion element, In an image reading device in which a conversion element performs shading correction on image data obtained by reading an image of a document, the image reference unit is provided at the second position, and the reading unit is configured to read the first image. When moving from the position to the second position, the light source is turned on from a predetermined position, the light source is further turned on for a predetermined time at the second position, and then the light source is turned off. When moving from the position to the first position, a light source control device that turns on the light source, and the photoelectric conversion element reads the image reference unit while the light source is turned on in the image reference unit, Thereafter, the photoelectric conversion element reads the image reference unit in a state where the light source is turned off, and when the reading unit moves from the second position to the first position, the light source is turned on for a predetermined time. A reading control device for causing the photoelectric conversion element to read the image of the document after the reading. 9. The image reading apparatus according to claim 5, wherein said reading window is provided at a bottom portion of said casing, and has a viewing window at the top of said casing through which said reading window allows a user to view a document. apparatus. 10. The image reading apparatus according to claim 5, wherein the reading window is formed on an upper portion of the casing, and a document is placed on the reading window. 11. The image reading device according to claim 9, wherein the casing has a grip on the first position side.