JP2001352455A - Image reader and image-reading method, and original protective sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image reader and an image reading method that can accurately correct colors of image data read by an image read head, when reading an image of an original. SOLUTION: Since the image read head 4 moves to a position, at which the head 4 can scan thermosensitive discoloring ink applied on protection sheets with an original 5 in-between, a detection LED approaches a thermosensitive discoloring ink section and the thermosensitive discoloring ink discolors, depending on a temperature of the LED. The image read head 4 reads the color of the discolored thermosensitive discoloring ink, converts analog color data of the thermosensitive discoloring ink by each scanning into digital data, compares the digital data with a digital reference temperature which have been stored in advance in an image recorder main body 1, to calculate a correction value and adjusts a volume control adjusting an output of the analog image data of the original 5 by each scanning outputted from the image read head 4 according to the correction value, so as to correct the color of the image data of the original 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an image reading apparatus and method, and an original protection sheet.

[0002]

2. Description of the Related Art A conventional image recording apparatus on which an image reading head can be mounted includes a conveying roller for conveying a document in a conveying direction (sub-scanning direction), and a driving belt on a guide shaft in a direction perpendicular to the conveying direction (main direction). (Scanning direction).

An image recording head for recording data on recording paper is removably mounted on the carriage, and the image recording head is composed of any one of dot impact, thermal transfer, ink jet, and the like.

Further, in the present image recording apparatus, the image recording head can be replaced with an image reading head, and an image on a document can be read by the image reading head. The image reading head includes an LED for irradiating the document with light, and a sensor for receiving reflected light from the document and performing photoelectric conversion.

When an image reading head reads an image recorded on an original, the amount of irradiation light changes in accordance with the temperature of the LED. Therefore, if the temperature of the LED changes, the color of the image recorded on the original will change. Are the same, the amount of reflected light from the document changes, and the image reading head cannot perform accurate image reading. Therefore, the image reading head detects the temperature inside the main body by a thermistor installed on the carriage substrate or the main body substrate located on the back of the carriage, and corrects the color of the image data read by the image reading head based on the value. I was

[0006]

However, in the conventional image reading apparatus, since the installation position of the thermistor is far from the image reading head, the temperature of the LED itself cannot be measured, and the image reading head cannot read the image. The color correction of the image data was inaccurate.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an image reading apparatus and method capable of accurately correcting the color of image data read by an image reading head.

[0008]

In order to achieve the above object, an image reading apparatus according to claim 1 irradiates an original with light and photoelectrically converts reflected light from the original to form an image on the original. In the image reading apparatus provided with an image reading means for reading a color, the image reading means is configured to read a color of a thermosensitive color change paint that changes color according to a temperature, and the image reading apparatus reads the color by the image reading means. A color correction unit configured to correct a color of the image of the document read by the image reading unit based on information on a color of the thermosensitive color change paint.

According to a second aspect of the present invention, in the image reading apparatus of the first aspect, a recording unit for recording an image on recording paper, and one of the image reading unit and the recording unit is detachably mounted. It is characterized by comprising a mounting means, and a moving means for moving the mounting means along the recording paper or the document.

According to a third aspect of the present invention, in the image reading apparatus according to the first or second aspect, the thermosensitive color-changing paint is applied to a document protection sheet which protects the document and is conveyed together with the document. It is characterized by that.

According to a fourth aspect of the present invention, in the image reading apparatus according to the first or second aspect, the thermochromic paint is directly applied to the original.

According to a fifth aspect of the present invention, in the image reading apparatus of the first or second aspect, the thermosensitive color change paint is applied to a main body of the image reading apparatus.

According to a sixth aspect of the present invention, in the image reading apparatus according to any one of the first to fifth aspects, the image reading means reads an image of the document in a predetermined number of lines in the main scanning direction. Each time, the color of the thermosensitive color change paint is read.

According to a seventh aspect of the present invention, in the image reading apparatus according to any one of the first to sixth aspects, the color correction means converts the color information of the thermosensitive color change paint to a reference temperature. The color of the image of the document read by the image reading unit is corrected based on a correction value obtained by comparing the information with the corresponding color information.

According to a still further aspect of the present invention, there is provided an image reading method for reading an image of an original by irradiating the original with light and photoelectrically converting reflected light from the original. A paint color reading step of reading the color of the thermochromic paint, and a color correcting step of correcting the color of the read document image based on the read information on the color of the thermosensitive paint. I do.

According to a ninth aspect of the present invention, in the image reading method of the eighth aspect, the step of reading the paint color comprises the step of: detecting the color change of the thermosensitive element every time the image of the original is read in a predetermined number of lines in the main scanning direction. The color of the paint is read.

According to a tenth aspect of the present invention, in the image reading method of the eighth or ninth aspect, the color correction step compares the color information of the thermosensitive color change paint with the color information for a reference temperature. The color of the image of the read document is corrected based on the correction value obtained as described above.

According to a eleventh aspect of the present invention, there is provided an original document protection sheet which is supplied to the image reading apparatus according to the first or second aspect and protects the original. It is characterized in that it is applied in a range readable by the image reading means.

According to a twelfth aspect of the present invention, there is provided the document protection sheet according to the eleventh aspect, wherein the thermosensitive color change paint is applied outside a range of the document.

According to a thirteenth aspect of the present invention, there is provided the document protection sheet according to the eleventh or twelfth aspect, wherein the thermosensitive color-changing paint is applied to both sides in the main scanning direction outside the range of the document. I do.

According to a fourteenth aspect of the present invention, in the document protection sheet according to any one of the eleventh to thirteenth aspects, the thermosensitive color-changing paint is applied over a length of the document in the sub-scanning direction. It is characterized by being performed.

According to a fifteenth aspect of the present invention, there is provided a document protection sheet comprising a transparent sheet for covering the document and a sheet on which the document is placed.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an image reading apparatus according to an embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a perspective view showing a schematic configuration of an image reading apparatus according to an embodiment of the present invention.

In FIG. 1, the image reading apparatus according to the present embodiment is an image recording apparatus 1 on which an image reading head can be mounted.

The image recording apparatus 1 has a platen 7 for transporting the original 5 in a transport direction (sub-scanning direction) indicated by a dashed arrow in FIG. 1 and a direction parallel to the platen 7, that is, a direction perpendicular to the transport direction ( Guide shafts 8A and 8B arranged along the main scanning direction) and a carriage 2 (mounting means) movably mounted on the guide shafts 8A and 8B. The carriage 2 is fixed to a drive belt 10 (drive means) driven by a drive motor 9 (drive means), and is driven along the guide shafts 8A and 8B.
It moves by the driving force from zero.

An image recording head 3 is detachably mounted on the carriage 2, and image data can be recorded on the recording paper 6 held on a platen 7 by the image recording head 3. In the present image recording apparatus 1, the image recording head 3 is replaceable with the image reading head 4, and the image reading head 4 can read an image of the document 5 held on the platen 7.

FIG. 2 is a schematic diagram showing a schematic configuration of the image reading head 4 mounted on the image recording apparatus 1 of FIG.

In FIG. 2, the image reading head 4 has a substantially rectangular parallelepiped housing 11, and the housing 11 has an electric circuit board 12 inside thereof. The electric circuit board 12 receives the reflected light from the document 5 via the lens 17, the mirror 16 and the lens 18, and photoelectrically converts the LED 13 to irradiate the document 5 held on the platen 7 with light through the lens 15. And a main component such as an IC for performing circuit control, A / D conversion, and image processing, and electrical components such as a resistor, a capacitor, a coil, and an oscillator (not shown). It is installed. The image data processed by the IC is sent to a main unit (not shown) and further sent to a host computer (not shown).

FIG. 3 is a diagram showing the configuration of the document protection sheet according to the embodiment of the present invention.

The document protection sheet 20 includes a white sheet 22 on which the document 5 is placed, and a transparent sheet 21 that faces the sheet 22 and sandwiches the document 5 so as to cover the surface of the document 5 on which an image is recorded. Prepare.

The outer surface of the sheet 21 is coated with a thermosensitive color changing ink 23 that changes color according to the temperature. The thermosensitive color changing ink 23 is, for example, Thermopaint (trade name of NOF Engineering Co., Ltd.). The thermosensitive color changing ink 23 is applied to the sheet 2
1 in the horizontal direction of the original 5 in the direction (main scanning direction) orthogonal to the conveying direction (sub-scanning direction) of the original 5 indicated by the arrow L in the drawing, 5 is applied in the transport direction L, and is applied beyond the length of the original 5 in the transport direction from just before the reading start position of the original 5. When the document protection sheet 20 is supplied to the image recording apparatus 1 with the document 5 sandwiched therebetween, and the image of the document 5 is read by the image reading head 4, the LED 13 approaches the thermosensitive color changing ink 23. 23
Changes color according to the temperature of the LED 13.

Hereinafter, the operation of the image reading apparatus according to the first embodiment of the present invention will be described with reference to FIG.

FIG. 4 is a flowchart of a color correction process for image data executed by the image reading apparatus according to the embodiment of the present invention.

When the document protection sheet 20 sandwiching the document 5 is supplied to the image recording apparatus 1 and held by the platen 7, the image reading head 4 mounted on the carriage 2
Starts reading the image of the original 5 (step S1).
The image reading head 4 moves to the position where the thermosensitive color changing ink 23 applied on the sheet 21 is scanned.
D <b> 13 approaches the thermosensitive color changing ink 23, and the thermosensitive color changing ink 23 changes color according to the temperature of the LED 13. At this time,
The image reading head 4 reads the discolored color of the thermosensitive color changing ink 23 (step S2), and digitally converts the analog value of the color data of the thermosensitive color changing ink 23 for each scan by an IC provided on the electric circuit board 12. (Step S
3) A correction value is calculated by comparing the digital value stored in advance in the main body of the image recording apparatus 1 with the reference temperature value (step S4), and each scan output from the image reading head 4 is calculated according to the correction value. The color correction of the image data of the document 5 is performed by adjusting the volume for adjusting the output of the analog value of the image data of the document 5 for each document (step S).
5) (Color correction means).

According to the first embodiment, the LED 13
The temperature of the LED 13 itself can be measured by reading the color of the thermosensitive color changing ink 23 that changes color in accordance with the temperature of the original, and the color of the image data of the original 5 read by the image reading head 4 can be accurately corrected. Can be.

In the present embodiment, the thermosensitive color changing ink 2
Reference numeral 3 denotes a document 5 outside the range of the document 5 on the sheet 21.
May be applied on both sides in the main scanning direction. Thus, by reading the color of the thermosensitive color changing ink 23 at the start and the end of each scan, it is possible to cope with a variation in the temperature of the LED 13 during each scan, and the original read by the image reading head 4 is read. 5 can be accurately corrected.

Also, without using the original protection sheet 20, the thermosensitive color-changing ink 23 is directly applied on the platen 7 to the original 5
May be applied outside the range. As a result, the manuscript protection sheet 20 becomes unnecessary, so that the number of components can be reduced.
It is possible to keep costs low.

Further, the analog value of the image data of the document 5 output from the image reading head 4 for each scan may be converted into a digital value, and the converted digital value may be corrected according to the correction value. As a result, the color of the image data of the document 5 can be accurately corrected.

[0040]

As described above in detail, according to the image reading apparatus of the first aspect and the image reading method of the eighth aspect, when reading an image of a document, the image reading means is controlled according to the temperature of the image reading means. By reading the color of the discolored thermochromic paint, the color of the image data read by the image reading means can be accurately corrected.

According to the image reading apparatus of the second aspect,
Since the recording means and the image reading means can be exchanged and mounted on the mounting means, using the same image reading apparatus,
It is possible to read an image of a document and record an image on a recording sheet.

According to the image reading apparatus of the third aspect,
Since the thermosensitive color change paint is applied on the sheet, it is possible to read the image of the document without soiling the peripheral portion.

According to the image reading apparatus of the fourth or fifth aspect, since a document protection sheet is not required, the number of components can be reduced, and the cost can be reduced.

According to the image reading apparatus of the sixth aspect and the image reading method of the ninth aspect, the image reading means comprises:
Since the image reading means reads the color of the thermosensitive color change paint every time the image of the document is read in the predetermined number of lines in the main scanning direction, it is possible to precisely cope with the temperature variation of the image reading means, and to improve the accuracy of the correction value. It is possible to improve.

According to the image reading apparatus of the present invention, the information on the color of the thermosensitive color-change paint read by the image reading means is compared with the information on the value of the reference temperature. For the calculation, it is possible to further improve the accuracy of the correction value.

According to the thirteenth aspect of the present invention, the color of the thermosensitive color change paint at the start and end of each scan is read, so that it is possible to cope with the temperature variation of the image reading means during each scan. Is possible, and the accuracy of the correction value can be improved.

According to the document protecting sheet of the present invention, since the change in temperature of the image reading means during reading of the image of the document can be read in detail, it is possible to cope with the temperature variation of the image reading means during reading of the image of the document. Becomes possible,
It is possible to further improve the accuracy of the correction value.

According to the document protecting sheet of the present invention, since the document is sandwiched between the transparent sheet and the white sheet of the document protecting sheet, the image of the document can be read without soiling the document.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a schematic configuration of an image reading apparatus according to an embodiment of the present invention.

FIG. 2 is a schematic diagram showing a schematic configuration of an image reading head 4 mounted on the image recording apparatus 1 of FIG.

FIG. 3 is a diagram illustrating a configuration of a document protection sheet according to the embodiment of the present invention.

FIG. 4 is a flowchart of color correction processing of image data executed by the image reading device according to the embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Image recording apparatus 2 Carriage (mounting means) 3 Image recording head 4 Image reading head 5 Original 6 Recording paper 7 Platen 8A, 8B Guide shaft 9 Drive motor (drive means) 10 Drive belt (drive means) 11 Housing 12 Electric circuit Substrate 13 LED 14 Sensor 15, 17, 18 Lens 16 Mirror 20 Original Protective Sheet 21, 22 Sheet 23 Temperature-sensitive discoloration ink (temperature-sensitive discoloration paint)

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H04N 1/04 H04N 1/04 D 5C079 1/60 1/40 D F term (Reference) 2G020 AA08 DA05 DA65 DA65 5B057 AA11 BA02 CA01 CA12 CB01 CB16 CC01 CE17 5C062 AB17 AB36 AC21 5C072 AA01 BA12 BA19 NA02 QA16 QA20 UA18 XA01 5C077 LL19 MM27 MP08 PP37 PP71 PP77 SS01 SS02 TT02 5C079 JA01 JA21 JA27 LA02 NA29 NA03 NA21

Claims (15)

[Claims] 1. An image reading apparatus, comprising: an image reading device that irradiates a document with light and photoelectrically converts reflected light from the document to read an image of the document. The image reading device is configured to read the color of the thermosensitive color changing paint that changes color, and the image reading device reads the original read by the image reading device based on information on the color of the thermosensitive color changing paint read by the image reading device. An image reading apparatus comprising a color correction unit for correcting the color of the image. 2. A recording means for recording an image on recording paper, a mounting means for removably mounting one of the image reading means and the recording means, and moving the mounting means along the recording paper or the original. 2. The image reading apparatus according to claim 1, further comprising a moving unit that moves the image. 3. The image reading apparatus according to claim 1, wherein the thermosensitive color-changing paint is applied to a document protection sheet that protects the document and is conveyed together with the document. 4. The image reading apparatus according to claim 1, wherein the thermosensitive color change paint is applied directly to the document. 5. The image forming apparatus according to claim 1, wherein the thermosensitive color change paint is applied to a main body of the image reading device.
An image reading device according to claim 1. 6. The image reading device according to claim 1, wherein the image reading unit reads the color of the thermosensitive color change paint every time the image of the document is read by a predetermined number of lines in the main scanning direction. An image reading device according to the item. 7. A document read by said image reading means based on a correction value obtained by comparing color information of said thermosensitive color-changing paint with color information corresponding to a reference temperature. The image reading apparatus according to claim 1, wherein the color of the image is corrected. 8. An image reading method for reading an image of an original by irradiating the original with light and photoelectrically converting reflected light from the original, wherein the color of a thermosensitive color change paint that changes color in accordance with temperature is read. An image reading method, comprising: a color reading step; and a color correction step of correcting a color of the read document image based on the read color information of the thermosensitive color change paint. 9. The image reading apparatus according to claim 8, wherein in the step of reading the paint color, the color of the thermosensitive color change paint is read each time the image of the document is read by a predetermined number of lines in the main scanning direction. Method. 10. The color correcting step includes: correcting a color of the read document image based on a correction value obtained by comparing color information of the thermochromic paint with color information for a reference temperature. 10. The correction according to claim 8, wherein the correction is performed.
The image reading method described in the above. 11. A document protecting sheet which is supplied to the image reading apparatus according to claim 1 and protects the document, wherein the thermosensitive color-changing paint which changes color in accordance with temperature is readable by the image reading means. A document protection sheet, which is applied to an area. 12. The document protection sheet according to claim 11, wherein the thermochromic paint is applied outside the range of the document. 13. The document protection sheet according to claim 11, wherein the thermosensitive color change paint is applied to both sides of the document in the main scanning direction outside the range. 14. The document protection sheet according to claim 11, wherein the thermosensitive color changing paint is applied over a length of the document in the sub-scanning direction. 15. The document protection sheet according to claim 11, comprising a sheet on which the document is placed, and a transparent sheet covering the previously described document.