JPH08214125A - Image reader and holder used for same - Google Patents

Abstract

PURPOSE: To obtain the image reader in which an image is read at an optimum exposure level even when a holder is in use. CONSTITUTION: When a holder 19 to read an image of a read object 2 via a transparent member 19a is in use, the use of the holder 19 is detected by reading a recognition pattern 15 arranged to the holder 19. When a recognition pattern 15 is detected, the effect of reading the image via the transparent member 19a is eliminated by using a reference density plate 16 arranged to the holder 19 to adjust the exposure.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image reading device and a holder used therefor.

[0002]

2. Description of the Related Art An image reading device is known as a device for reading image information of an object to be read, such as a photograph or a printed matter, and converting it into an electric signal.

FIG. 4 is a structural view showing the main part of this type of image reading apparatus. As shown in the figure, this image reading apparatus illuminates an object to be read 2 with an illuminating means 1 such as a fluorescent lamp, and an image of the object to be read 2 obtained by illuminating with this illuminating means 1 is a mirror 3, a lens 4, etc. An image is formed on the sensor 5 through the optical system of. This sensor 5 is a CCD
Since it is a set of image pickup elements, which is usually a one-dimensional line sensor, together with this sensor 5, the illumination means 1,
The image reading unit 6 configured by integrating the mirror 3 and the lens 4 moves in the direction perpendicular to the longitudinal direction of the sensor 5 (hereinafter referred to as the sub-scanning direction), and the image of the reading target 2 having a planar spread. It is configured to scan and read the whole. When the sensor is an area sensor in which the image pickup elements are arranged in a two-dimensional plane, it may not be necessary to scan.

The image formed on the sensor 5 is stored in a memory as electrical image information, or is supplied to a television monitor, a printer or the like after being subjected to a predetermined correction.

The reading object 2 is placed on a reading window 7 which is a flat surface formed of a transparent member such as glass so that the reading surface 2a faces the mirror 3 and an image can be formed on the sensor 5. Further, in order to secure a constant exposure level during image reading, a reference level is set so that the mirror 3 can face each other at the starting point position in the scanning direction to determine a reference level (usually a white level) that serves as a reference prior to image reading. A concentration plate 8 is provided. The reference density plate 8 is formed so as to have a uniform density, and the one formed in white is called a reference white plate.
This is normally used.

Thus, when the image is read by the image reading apparatus, the object 2 to be read is placed on the reading window 7 with its reading surface 2a facing down, and the image reading unit 6 is run in the sub-scanning direction. Thus, the images are sequentially captured by the sensor 5 and a predetermined electrical process is performed. The electrical processing at this time is performed by performing exposure adjustment so that the white level becomes constant with reference to the level (for example, white level) of the reference density plate 8 taken in prior to the reading of the reading target 2. .

[0007]

By the way, while the image area of the image reading device is constant, the size of the read object 2 is various. Therefore, in a state in which the reading target 2 is turned upside down (a state in which the reading surface 2a faces downward and the mirror 3 faces each other), for example, a specific portion such as a portion in which a specific person is photographed is read, for example, the reading window 7. It is not easy to occupy the desired position, such as locating it in the center of the.

A holder has been proposed as an auxiliary tool for occupying such a specific portion of the read object 2 at a desired position.

FIG. 5 is an explanatory view conceptually showing an example of this holder. As shown in the figure, the holder 9 includes a transparent member 9a such as glass and a hinge portion 9b for the transparent member 9a.
And a pressing plate 9c which rotates around the center of the pressing member 9c, and the reading target 2 is held between the transparent member 9a and the pressing plate 9c. At this time, the size of the holder 9 is predetermined so as to have a predetermined relationship with the reading window 7.

Thus, the position of the reading target 2 in the holder 9 is adjusted by placing the reading target 2 on the pressing plate 9c with the pressing plate 9c facing down and the transparent member 9a facing upward with the reading surface 2a facing upward. After that, the object 2 to be read is held by the holder 9, and in this state, the transparent member 9a, that is, the reading surface 2a is placed on the reading window 7 of the image reading device.

By using the holder 9, it is possible to easily occupy a specific portion of the reading object 2 at a desired position, but when the holder 9 is used, a new problem occurs. That is, in the image reading apparatus, as described above, the level is adjusted based on the image on the reference density plate 8 before image reading. This is done when the object 2 to be read is placed directly on the reading window 7. When the holder 9 is used, the object to be read 2 based on the thickness t of the transparent member 9a is adjusted so that the level is adjusted to the optimum level.
As the distance between the mirror 3 and the mirror 3 changes, the distance from the illumination unit 1 to the reading target 2 increases, and the transparent member 9
Since the light amount is reduced due to the transmittance of a, the exposure is insufficient and the optimum exposure level cannot be secured.

Further, the use of the holder 9 causes the following problems.

(1) Due to the thickness t of the transparent member 9a of the holder 9, the light distribution characteristic may change as the reading object 2 moves away from the illuminating means 1, and in this case, the illuminating means 1 The shading characteristic changes along the longitudinal direction.

(2) If the transparent member 9a has a light color, or if it has a color due to aging, the accuracy of the white balance correction based on the reference density plate 8 becomes poor.

(3) Due to the thickness of the transparent member 9a of the holder 9, when the distance from the optical system to the reading object 2 becomes long, only the image in the main scanning direction (direction perpendicular to the sub scanning direction) is reduced, Since the sub scanning direction, which is the moving direction of the image reading unit 6, does not change, the aspect ratio of the reproduced image changes,
It becomes a distortion of the reproduced image and becomes apparent.

In view of the above-mentioned conventional technique, the present invention can not only read an image at an optimum exposure level even when a holder is used, but can also eliminate all the above-mentioned problems when the holder is used. An object is to provide an image reading device and a holder used for the same.

[0017]

The invention for achieving the above object is characterized by having the following constitution. A reading object that holds a reading object having image information, such as a photograph or a printed matter, that is the object of image reading, and uses a holder that is mounted on the reading window of the image reading device through a transparent member and is illuminated by illumination means. The image of the reading surface of
Indicates that a holder is placed in an image reading apparatus that obtains image information as an electric signal by forming an image on a sensor through an optical system such as a reading window and a lens and performing predetermined electrical processing. In the holder detection mode, the exposure level must be increased by a certain amount.

The exposure level is increased by a certain amount by increasing the light amount of the illumination means by a certain amount.

The exposure level is increased by a certain amount by extending the exposure time of the sensor by a certain amount.

In the electrical processing, the exposure level is increased by a certain amount by increasing the amplification gain of the output signal of the sensor by a certain amount.

[0021] A reading object having image information to be read, such as a photograph or a printed matter, is held, and a holder mounted on the reading window of the image reading device through a transparent member is used and illuminated by an illuminating means. In the image reading device for obtaining the image information which is an electric signal by forming an image of the reading surface of the read object on the sensor through an optical system such as a reading window and a lens and performing a predetermined electrical process, In the holder detection mode, which indicates that the holder is placed, the exposure setting is performed using the reading target and the reference density plate arranged on the same plane where the reading target exists in the holder. thing.

A reading object such as a photograph or a printed matter having image information to be read is held and a holder mounted on a reading window of the image reading device through a transparent member is used and illuminated by an illuminating means. In the image reading device for obtaining the image information which is an electric signal by forming an image of the reading surface of the read object on the sensor through an optical system such as a reading window and a lens and performing a predetermined electrical process, In the holder detection mode indicating that the holder is placed, the shading correction is performed in the holder by using the reading target and the reference density plate arranged on the same plane where the reading target exists. thing.

A reading object having image information, such as a photograph or a printed matter, which holds image information to be read is held, and a holder mounted on a reading window of the image reading device through a transparent member is used and illuminated by an illuminating means. In the image reading device for obtaining the image information which is an electric signal by forming an image of the reading surface of the read object on the sensor through an optical system such as a reading window and a lens and performing a predetermined electrical process, In the holder detection mode indicating that the holder is placed, the white balance correction is performed using the reading target and the reference density plate arranged on the same plane where the reading target exists in the holder. What I did.

A reading object having image information to be read, such as a photograph or a printed matter, is held, and a holder mounted on a reading window of the image reading device through a transparent member is used and illuminated by an illuminating means. The image of the read surface of the read object is formed on a line sensor through an optical system such as a lens, and the image reading unit having the optical system and the line sensor is moved in one direction to read the image of the read object. In the image reading device configured to process the output signal of the line sensor and convert the image into an electrical image signal while reading the entire Sometimes
The magnification of the optical system is changed so that the aspect ratio of the image to be read by the line sensor matches.

The object to be read having image information, such as a photograph or a printed matter, is held, and a holder mounted on the reading window of the image reading device through a transparent member is used and illuminated by an illuminating means. The image of the read surface of the read object is formed on a line sensor through an optical system such as a lens, and the image reading unit having the optical system and the line sensor is moved in one direction to read the image of the read object. In the image reading apparatus configured to process the output signal of the line sensor to convert the image into an electrical image signal while reading the entire image, the holder detection mode indicating that the holder is placed is displayed. ,
The image reading pitch of the line sensor is changed in accordance with the movement of the image reading unit in one direction so that the images to be read by the line sensor have the same aspect ratio.

A transparent member which is a flat plate and a pressing member which is a flat plate are arranged so that an object to be read, such as a photograph or a printed matter, can be held between them, and the reference density plate is flush with the inner surface of the transparent member. Is installed.

A transparent member which is a flat plate and a pressing member which is a flat plate are arranged so that a reading object such as a photograph or a printed matter can be held between them, and the reference density plate is flush with the inner surface of the transparent member. And have identification means such as a bar code indicating that it is a holder.

[0028]

According to the present invention having the above structure, the presence of the holder is detected to adjust the exposure level, shading and white balance, and when the holder is present, that is, the image to be read is read through the transparent member of the holder. Adjust to the optimum exposure level and white balance corresponding to the case. For the change in the distance to the object to be read, the aspect ratio of the reproduced image is changed by changing the magnification of the optical system or the reading pitch of the image signal from the sensor accompanying the movement of the image reading unit. There is no such thing.

[0029]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 is a structural diagram showing a main part of an image reading apparatus according to an embodiment of the present invention together with a block diagram of its control system and a holder. The image reading apparatus of the present embodiment is different from the conventional image reading apparatus in that a means for detecting the holder 19 and an exposure level adjusting means when the use of the holder 19 is detected are added, but the image reading apparatus is different. The basic structure of the device is the same as that of the image reading device shown in FIG. Therefore, the same parts as those in FIG.

As shown in FIG. 1, the image signal converted into an electric signal by the sensor 5 is converted into a digital signal by the A / D converter 11 after its gain is controlled by the gain controller 10, and digitized. It is output as the image signal S ₀ .

The control unit 12 includes the gain controller 10 and the A / D converter 11 as well as the conventional dimming circuit 13.
And a predetermined control for the timing circuit 14, and based on the image signal S ₀ when the image of the reference density plate 8 is read, the gain controller 10 and the dimming circuit are controlled so that this becomes a predetermined level. Exposure adjustment is performed via 13 and the timing circuit 14. Further, when the control unit 12 according to the present embodiment reads the recognition pattern 15 that the holder 19 indicates that it is the holder 19, the image signal S ₀ based on the reference density plate 16 that is read next to the recognition pattern 15 is read. The gain controller 10, the dimming circuit 13, and the timing circuit 14 are controlled to adjust the exposure on the basis of the level.

At this time, the dimming circuit 13 controls the light quantity of the illuminating means 1. The timing circuit 14 controls the read timing of the charges accumulated in the sensor 5, that is, the exposure time.

The holder 19 is a transparent member 19a such as glass.
And a holding plate 19c which rotates around the hinge portion 19b with respect to the transparent member 19a, and the object 2 to be read is held between the transparent member 19a and the holding plate 19c. At this time, the size of the holder 19 is predetermined so as to have a predetermined relationship with the reading window 7.

The holder 19 according to this embodiment has a recognition pattern 15 and a reference density plate 16 for identifying the holder 19, as clearly shown in FIG. The recognition pattern 15 and the reference density plate 16 are rectangular members extending in the main scanning direction (the direction perpendicular to the sub-scanning direction) and are flush with the inner surface of the transparent member 19a so as to be adjacent to each other from the most starting point side in the sub-scanning direction in the same direction. It is arranged on the transparent member 19a above. That is, the reference density plate 16 is the transparent member 19a.
It is located on the same plane as the reading surface 2a of the reading object 2 held between the holding plates 19c. Also, this reference concentration plate 1
Similar to the reference density plate 8, 6 also has a uniform density throughout, and is normally a white plate.

According to the present embodiment, the holder 19 is read.
Hold the object to be picked up 2 and place it on the reading window 7, and in this state
When reading the image on the reading surface 2a of the reading target 2,
Image signal S of the recognition pattern 15₀By the processing of holder 19
Knowing that you are using a standard concentration plate 1 to read continuously
Image signal S of 6₀The same plane as the reading surface 2a
Know the reference level in. As a result, the control unit 12
Image signal S of the degree plate 16 ₀Based on the reference level based on
To adjust the exposure.

The detection of the use of the holder 19 is not limited to the recognition pattern 15 described above. A signal indicating that the holder is in the use mode may be supplied to the control unit 12 by some means. For example, as shown in FIG. 3A, a holder 20 is provided with a protrusion 20 a, and when the holder 20 is used, the protrusion 20 a penetrates a hole of the main body 17 of the image reading apparatus and is arranged in the main body 17. The switch 21 is operated, as shown in FIG. 3B, the tip of the protrusion 20a of the holder 20 is detected by the photocoupler 22, and as shown in FIG. 3C.
It is conceivable that the magnetism of the magnet 23 arranged in the holder 21 is detected by the magnetic sensor 24 arranged in the main body 17. Alternatively, it may be manually set that the holder is in the use mode.

In the above embodiment, the exposure adjustment is performed by using the reference density plate 16, but the present invention is not limited to this. When it is detected that the holder is in the use mode, the exposure level may be increased by a certain amount. The adjustment of the exposure level in this case may be any of the gain adjustment by the gain controller 10, the light amount adjustment by the dimming circuit 13, and the exposure time adjustment by the timing circuit 14.

Further, in the controller 12, the reference density plate 16
Image signal S₀Not only level adjustment but also standard density plate 1
Image signal S of 6₀Shading correction and h
It is also possible to correct the balance. Sanawa
Then, shading correction and white balance correction itself
Is the same as before, but the standard for both corrections
Image signal S₀Is different. Conventionally, all are standard density
Image signal S based on plate 8 ₀Was using.

Here, the shading correction means
Due to the characteristic that the amount of illumination light by the illuminating means 1 is the largest in the central portion in the main scanning direction and decreases toward both ends, the phenomenon that the reproduced image becomes darker toward the end portion in the main scanning direction occurs as it is. However, by adjusting the level of the image signal S ₀ , the influence of the characteristics of the illuminating means 1 as described above is canceled to obtain a reproduced image of uniform brightness.

Further, due to the thickness t of the transparent member 19a of the holder 19, if the distance from the optical system such as the lens 4 to the reading object 2 becomes long, only the image in the main scanning direction (sub scanning direction) is reduced. To solve the problem that the aspect ratio of the reproduced image changes, the magnification of the optical system or the read pitch of the image signal from the sensor 5 accompanying the movement of the image reading unit 6 in the sub-scanning direction is set to the thickness of the transparent member 19a. It may be configured so as to change in correspondence with the height t.

Specifically, when the presence of the holder 19 is detected, the control unit 12 moves the lens 4 in the optical axis direction or inserts another lens on the optical axis of the lens 4. Can be realized by doing
Can be realized by controlling the moving mechanism of the image reading unit 6 and adjusting the moving speed in the sub-scanning direction.

Further, the thickness t of the transparent member 19a may be measured by a sensor and the accuracy thereof may be supplied to the control unit 12. If the holder 19 is standardized, the thickness t may be set. It can also be configured to be preset.

[0044]

As described above in detail with reference to the embodiments, according to the image reading apparatus of the present invention, when the image to be read is read through the holder, the transparent member of the holder is present. Since the exposure level is adjusted in anticipation, the image to be read can be read at the optimum exposure level despite the presence of the transparent member.

Further, according to the holder of the present invention, the exposure can be adjusted by the reference density plate of the holder.
The image to be read can be read at the optimum exposure level.

Further, since the shading correction and the white balance correction are also based on the image signal of the reference density plate of the holder, more appropriate correction can be made in consideration of the use of the holder.

[Brief description of drawings]

FIG. 1 is a structural diagram showing a main part of an image reading apparatus according to an embodiment of the present invention, along with a block diagram of its control system and a holder.

FIG. 2 is a plan view showing a holder according to an embodiment of the present invention with a part thereof cut away.

FIG. 3 is an explanatory diagram illustrating a holder detection structure according to an embodiment of the present invention.

FIG. 4 is a structural diagram showing a main part of an image reading apparatus according to a conventional technique.

FIG. 5 is a perspective view showing a holder according to a conventional technique.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Illuminating means 2 Reading target 2a Reading surface 3 Mirror 4 Lens 5 Sensor 7 Reading window 8 Reference density plate 10 Gain controller 12 Control part 13 Light control circuit 14 Timing circuit 15 Recognition pattern 16 Reference density plate 19 Holder 19a Transparent member 19c Holding plate

Claims (11)

[Claims] 1. A holder for holding a reading object having image information, such as a photograph and a printed matter, which is an object of image reading, and a holder mounted on a reading window of an image reading device through a transparent member, and illuminating means. An image reading device which obtains image information which is an electric signal by forming an image of a reading surface of a reading object illuminated by the image on a sensor through an optical system such as a reading window and a lens and performing a predetermined electrical processing. In the image reading device, the exposure level is increased by a fixed amount in the holder detection mode indicating that the holder is mounted. 2. The image reading apparatus according to claim 1, wherein the exposure level is increased by a fixed amount by increasing the light amount of the illumination means by a fixed amount. 3. An image reading apparatus according to claim 1, wherein the exposure level is increased by a certain amount by extending the exposure time of the sensor by a certain amount. 4. The image reading apparatus according to claim 1, wherein the exposure level is increased by a fixed amount by increasing the amplification gain of the output signal of the sensor in the electrical processing. 5. A holder for holding a reading object having image information as an image reading object such as a photograph and a printed matter, and using a holder mounted on a reading window of the image reading device through a transparent member, and illuminating means. An image reading device which obtains image information which is an electric signal by forming an image of a reading surface of a reading object illuminated by the image on a sensor through an optical system such as a reading window and a lens and performing a predetermined electrical processing. In the holder detection mode, which indicates that the holder is mounted, the exposure setting is performed using the reading target and the reference density plate arranged on the same plane where the reading target exists in the holder. An image reading device characterized by being configured. 6. A holder for holding a reading object having image information, such as a photograph or a printed matter, which is an object of image reading, and using a holder mounted on a reading window of an image reading device through a transparent member, and illuminating means. An image reading device which obtains image information which is an electric signal by forming an image of a reading surface of a reading object illuminated by the image on a sensor through an optical system such as a reading window and a lens and performing a predetermined electrical processing. In the holder detection mode indicating that the holder is mounted, the shading correction is performed in the holder by using the reading target and the reference density plate arranged on the same plane where the reading target exists. An image reading device characterized by being configured. 7. A holder for holding a reading object having image information, such as a photograph and a printed matter, which is a target of image reading, and using a holder mounted on a reading window of an image reading device through a transparent member, and illuminating means. An image reading device which obtains image information which is an electric signal by forming an image of a reading surface of a reading object illuminated by the image on a sensor through an optical system such as a reading window and a lens and performing a predetermined electrical processing. In the holder detection mode indicating that the holder is placed, the white balance correction is performed using the reading target and the reference density plate arranged in the same plane where the reading target exists in the holder. An image reading device having the above-mentioned configuration. 8. A holder for holding a reading object having image information to be read, such as a photograph or a printed matter, and using a holder mounted on a reading window of an image reading device through a transparent member, and illuminating means. The image on the reading surface of the reading object illuminated by the image is formed on the line sensor through an optical system such as a lens, and the image reading unit having the optical system and the line sensor is moved in one direction to move the reading object. In the image reading device configured to process the output signal of the line sensor and convert the image into an electrical image signal while reading the entire image of the holder, holder detection indicating that the holder is mounted is detected. In the mode, the image is characterized in that the magnification of the optical system is changed so that the aspect ratio of the image to be read by the line sensor matches. Reader. 9. A holder for holding a reading object having image information as an image reading object such as a photograph or a printed matter, and using a holder mounted on a reading window of an image reading device through a transparent member, and illuminating means. The image of the reading surface of the reading object illuminated by the image is formed on the line sensor through an optical system such as a lens, and the image reading unit including the optical system and the line sensor is moved in one direction to move the reading object. In the image reading device configured to process the output signal of the line sensor and convert the image into an electrical image signal while reading the entire image of the holder, a holder detection mode indicating that the holder is placed. , The image read by the line sensor is moved in one direction so that the aspect ratios of the images to be read by the line sensor match. Image reading apparatus characterized by being configured to vary the pitch of the read. 10. A transparent member, which is a flat plate, and a pressing member, which is a flat plate, are configured so that a reading target such as a photograph or a printed matter can be held between them, and the reference surface is flush with the inner surface of the transparent member. A holder having a concentration plate. 11. A transparent member, which is a flat plate, and a holding member, which is a flat plate, are arranged so that an object to be read, such as a photograph or a printed matter, can be held between the two members, and the inner surface of the transparent member is used as a reference plane. A holder characterized in that it has a concentration plate and further has identification means such as a bar code indicating that it is a holder.