JPH11243468A - Image capturing device and protection material unclean unclean state decision method for the image capturing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily obtain a satisfactory image with an original S/N by recommending a user cleaning of a protective glass part, when white correction data exceeds a normal value at the time of white correction. SOLUTION: This device has a manuscript lighting means 101 for lighting the manuscript, a light collecting means 102 for collecting a reflected light from the manuscript, a light detection means 103 for detecting the collected light, a protection material 104 such as glass for protecting the manuscript lighting means 101 and the light collecting means 102, an accumulating means 108 for accumulating white correction data, on the basis of the white correction, a control means 106 that decides that a dirt or dust has stuck to the protective material 104, when the white correction data accumulated in the accumulating means 108 exceeds a normal value and control so as to perform warning, and a warning means 109 for notifying to the effect that dirt or dust has stuck to the protective material 104.

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 and a method for determining the contamination of a protective member in the image reading apparatus, and more particularly to a line image scanner or a facsimile or multifunction printer equipped with a line image scanner. More particularly, the present invention relates to an image reading apparatus suitable for such a case and a method for determining the contamination of a protective member in the image reading apparatus.

[0002]

2. Description of the Related Art Conventionally, the above line image scanner,
Alternatively, in an apparatus having an image reading function such as a facsimile or a multifunction printer equipped with a line image scanner, an image is read using a contact image sensor mounted in the apparatus. The contact image sensor mounted on this type of device is provided with a glass part for protecting the sensor, but conventionally, there is provided a means for detecting adhesion of dirt and dust on the glass part for protecting the contact image sensor. Had not been.
For this reason, white correction and image reading have been performed without detecting dirt or dust on the glass part for protecting the contact image sensor.

[0003]

However, the above-mentioned prior art has the following problems. That is, as described above, in the related art, when dust or dirt adheres to the glass part for protecting the contact image sensor, there is no means for detecting the dust or dirt. In some cases, black streaks and the like are generated due to the adhesion of dirt and the like, and an image in which an appropriate SN ratio cannot be obtained may be obtained. However, on the user side, there is a problem that it is almost impossible to cope with the problem in most cases because the cause of an image in which an appropriate S / N ratio such as the above-mentioned black streak cannot be obtained cannot be understood. .

[0004] The present invention has been made in view of the above-mentioned point, and more simply urges the user to clean the protective glass portion when the white correction data at the time of white correction exceeds a specified value. It is an object of the present invention to provide an image reading device capable of obtaining a good image with an original SN ratio and a method for determining the contamination of a protective member in the image reading device.

[0005]

In order to achieve the above object, according to the present invention, there is provided an original illuminating means for illuminating an original, a condensing means for condensing light reflected from the original, and a condensed light. An image reading device comprising: a light detecting unit for detecting the white light; and a protection member such as glass for protecting the original illuminating unit and the light condensing unit. Control means for determining that dirt, dust, or the like is attached to the protective member when the white correction data accumulated in the means exceeds a specified value, and performing an alarm, and dirt or dust on the protective member. And an alarm means for notifying the user that there is adhesion.

In order to achieve the above object, the invention according to claim 2 is characterized in that the prescribed value is a value obtained by adding a dark side variation of the light emission amount of the document illuminating means and a dark side variation of the light receiving amount of the light detecting means. Is the maximum value.

In order to achieve the above object, a third aspect of the present invention is characterized in that the white correction is performed by using a member such as a white sheet metal or a calibration sheet before reading an original or during calibration.

In order to achieve the above object, a fourth aspect of the present invention is characterized in that the alarm means notifies by a display that a dirt or dust adheres to the protection member and that the protection member is urged to be cleaned. And

In order to achieve the above object, a fifth aspect of the present invention is characterized in that the alarm means notifies by voice that the dirt or dust adheres to the protection member and that the protection member is urged to be cleaned. And

In order to achieve the above object, according to the invention of claim 6, it is possible to connect to a host device such as a computer, and to check the position of the protection member on the screen of the host device such as dirt or dust. It is characterized in that identification is possible.

In order to achieve the above object, the invention of claim 7 is characterized in that it can be applied to a line image scanner, a facsimile equipped with a line image scanner, a multifunction printer, and the like.

According to another aspect of the present invention, there is provided a document illuminating means for illuminating a document, a light collecting means for collecting light reflected from the document, and a light detecting means for detecting the collected light. And a protection member stain determination method in an image reading apparatus having a protection member such as glass for protecting the document illuminating means and the light condensing means, comprising: a storage step of storing white correction data based on white correction; When the white correction data accumulated in the step exceeds a prescribed value, it is determined that dirt or dust is attached to the protection member, and a control step is performed so that an alarm is issued. And an alarming step for notifying that there is an attachment or the like.

In order to achieve the above object, the invention according to claim 9 is characterized in that the prescribed value is a value obtained by adding a dark-side variation of a light emission amount of the document illuminating unit and a dark-side variation of a light receiving amount of the light detecting unit. Is the maximum value.

In order to achieve the above object, a tenth aspect of the present invention is characterized in that the white correction is performed using a member such as a white sheet metal or a calibration sheet before reading an original or during calibration.

In order to achieve the above object, the invention of claim 11 is characterized in that, in the warning step, a display is provided to notify a place where dirt or dust adheres to the protection member and a message prompting the cleaning of the protection member. And

In order to achieve the above object, a twelfth aspect of the present invention is characterized in that, in the warning step, a sound is issued to notify a place where dirt or dust adheres to the protection member and a prompt to clean the protection member. And

In order to achieve the above object, the invention according to the thirteenth aspect of the present invention is capable of specifying a portion where the protection member is attached to the protection member on a screen of a host device such as a computer to which an image reading device can be connected. There is a feature.

In order to achieve the above object, the invention of claim 14 is characterized in that it can be applied to a line image scanner, a facsimile equipped with a line image scanner, a multifunction printer, and the like.

[0019]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a functional block diagram showing a configuration of a main part of an image reading apparatus according to an embodiment of the present invention and corresponding to the claims. The image reading apparatus according to the embodiment of the present invention includes a document illuminating unit 101, a condensing unit 10
2. Image reading means 105 having light detection means 103 and protection member 104; control means 106;
7, storage means 108, and alarm means 109. In this case, the document illuminating unit 101 and the condensing unit 1 are used.
02, light detection means 103, protection member 104, control means 1
06, the storage means 108, and the alarm means 109 correspond to each component in the claims.

The function of each section will be described in detail. The image reading means 105 corresponds to the line image sensor 207 shown in FIG.
2. A process of reading an image from a document by the light detecting means 103 is performed. The document illuminating unit 101 corresponds to the LED array 213 in FIG. 2 and illuminates the document based on a light emission signal output from the control unit 106. The light collecting means 102
It corresponds to the lens array 215 of FIG. 2, and collects the reflected light when the light emitted from the document illuminating means 101 is reflected by the document. The light detecting means 103 corresponds to the phototransistor array 211 of FIG. 2 and detects the light collected by the light collecting means 102. The protection member 104 is a member that protects the document illumination unit 101 and the light collection unit 102,
For example, it is formed of glass or the like.

The control means 106 corresponds to the CPU 201 of FIG. 2 and accumulates in the accumulation means 108 based on white correction performed using a white sheet metal or a calibration sheet (described later) before reading an original or at the time of calibration. When the corrected white correction data exceeds the specified value, the protection member 1
It is determined that dirt, dust and the like are adhered to the control unit 04 and the alarm unit 109 is controlled to give an alarm to that effect. The document conveying means 107 includes the motor driving circuit 203 of FIG.
04, which corresponds to the document transport roller 205 and transports the document under the control of the control means 106. Storage means 10
Reference numeral 8 corresponds to the white correction data storage RAM 220 in FIG. 2, and stores white correction data under the control of the control unit 106. The alarm unit 109 notifies the user of a position where dirt or dust adheres to the protection member 104 and that the user is urged to clean the protection member 104 by, for example, display or sound based on the control of the control unit 106.

FIG. 2 is a block diagram showing an electrical configuration of the image reading apparatus according to the embodiment of the present invention. The image reading apparatus according to the embodiment of the present invention includes a CPU 201, a motor driving circuit 203, a motor 204, and a document conveying roller 20.
5, a gear or timing belt 206, a line image sensor 207, and a white correction data storage RAM 220. Further, the line image sensor 207
An SIC (Application Specified IC) 208, a shift register 209, a holding capacitor 210, a phototransistor array 211, an LED array 212, and a lens array 215 are provided. 2 in the figure
02 is a document to be read, 213 and 214 are light,
Reference numerals 216 to 219 and 221 indicate signal lines, and arrows indicate the direction in which the document is transported.

The structure of each of the above components will be described in detail.
Reference numeral 1 denotes a central processing unit that controls the above-described units, and executes processing as shown in flowcharts of FIGS. 5 and 6 described below based on a predetermined control program. The motor drive circuit 203 rotationally drives the motor 204 based on the motor drive signal 216 output from the CPU 201. The motor 204 transmits the rotation driving force to the document conveying roller 205 via a gear or a timing belt 206. Document transport roller 205 transports document 202 at a predetermined transport speed in the direction of the arrow in the figure. In this case, the document conveying path is configured so that the document 202 passes between the line image sensor 207 and the document conveying roller 205.

The white correction data storage RAM 220 stores data transferred from the CPU 201 during white correction. The line image sensor 207 includes the ASICs 208 to
An image is read from the document 202 by the lens array 215. The LED array 212 emits light 213 and is arranged so as to cover the width of the document 202. The lens array 215 collects the light 214 reflected by the document 202. Phototransistor array 211
Is a device for converting the light collected by the lens array 215 into electric charges, and is a photodetector having a number corresponding to each pixel. Note that the photodetector is not limited to the phototransistor array.

The holding capacitor 210 stores the charge converted from light by the phototransistor array 211. The shift register 209 includes the holding capacitor 21.
Image data is sequentially sent to the CPU 201 via the signal line 219 based on a voltage generated according to the amount of charge charged to zero. The ASIC 208 is an application specific IC including a timing generation circuit,
The timing for transferring the voltage of 0 to the shift register 109 is set.

The reading operation of the image reading apparatus having the above configuration will be described.
The LED array 212 covering the width of the document 202 emits light 213 according to the LED light emission signal 218 output from the CPU 201. Along with this, the light 214 reflected by the document 202 is condensed by the lens array 215 and enters the phototransistor array 211 (photodetector).
The incident light is converted from light into electric charges by the phototransistor array 211 and charged into the holding capacitor 210. A voltage is generated in accordance with the amount of electric charge charged in the holding capacitor 210, and the voltage is sequentially transmitted by the shift register 209 to the CPU 201 as image data via the signal line 219.

The timing of charging and discharging the charge from the phototransistor array 211 to the holding capacitor 210 and the timing of transferring the voltage of the holding capacitor 210 to the shift register 209 are determined by the signal line 2
17 is set by the ASIC 208 including the above-described timing generation circuit. The white correction data transferred from the line image sensor 207 to the CPU 201 during the white correction is
The data is stored in the white correction data storage RAM 220 via the signal line 221 by the CPU 201.

FIG. 3 is an explanatory view of a case where a white correction calibration sheet is used at the time of white correction in the image reading apparatus according to the embodiment of the present invention. FIG. FIG. 3B is an explanatory diagram showing dust and the like, FIG. 2B is an explanatory diagram showing the light and dark levels of the contact image sensor output, and FIG. 2 in the figure
08 denotes an ASIC, 212 denotes an LED array, 215 denotes a lens array, 221 denotes a calibration sheet for white correction, 223 denotes dirt / dust on a glass portion for protecting a contact image sensor, and an arrow denotes a document conveying direction.

FIG. 4 is a perspective view showing an example in which a white sheet metal for white correction is used at the time of white correction in the image reading apparatus according to the embodiment of the present invention. In the drawing, reference numeral 222 denotes a white metal sheet for white correction. Normally, in an image reading device using a contact image sensor, white correction is performed using a calibration sheet or sheet metal on a white background in order to correct variations in the LED light emission amount and the sensor light reception amount. At this time, if dirt, dust, or the like is attached to the glass part for protecting the contact image sensor, a graph as shown in FIG. 3 is obtained.
If there is dirt, dust, etc. that affects the image,
Since the output of the contact image sensor drops, a corresponding correction amount is required. That is, bit data that requires a correction amount equal to or greater than a certain specified value can be determined as dirt or dust adhering to the contact image sensor protecting glass.

Next, with reference to the flow charts of FIGS. 5 and 6, a process for judging the adhesion of dirt / dust on the glass portion for protecting the contact image sensor in the image reading apparatus according to the embodiment of the present invention having the above-described configuration will be described. I will explain while.

In accordance with the start of the white correction using the calibration sheet or the white sheet metal before the original reading or the calibration in the image reading apparatus (step S5).
01), output is started from the contact image sensor (line image sensor) 207 (step S50).
2). Subsequently, after the output data of the contact image sensor (line image sensor) 207 is subjected to A / D (analog / digital) conversion with, for example, about 8 bits (step S503), the white correction data is output via an arithmetic circuit such as the CPU 201. The white correction data is stored in the storage RAM 220 (step S504).

Thereafter, the CPU 201 compares the white correction data stored in the white correction data storage RAM 220 with a preset specified value (step S505). If the white correction data is equal to or less than the specified value, it is determined that there is no adhesion of dirt, dust, or the like on the glass part for protecting the contact image sensor (step S506). On the other hand, when the white correction data is equal to or more than the specified value (when there is bit data equal to or more than the specified value), it is determined that dirt, dust, or the like is attached to the contact image sensor protecting glass part (step S50).
7) The alarm means (see the alarm means 109 in FIG. 1) provided in the image reading apparatus displays or notifies by sound or the like that dirt or dust is attached to the glass part for protecting the contact image sensor. Then, the user is urged to clean the glass part for protecting the contact image sensor (step S508).

In the embodiment of the present invention, it is desirable that the above-mentioned specified value is the maximum value of the variation of the light emission amount on the dark side of the LED array 212 + the variation of the light reception amount of the phototransistor array 211 on the dark side. Further, since the output of the contact image sensor (line image sensor) 207 is sequentially output in the main scanning direction, the protection of the contact image sensor is performed on the application screen of a higher-level device (for example, a personal computer: PC) that controls the image reading device. It is also possible to specify the place where dirt, dust and the like adhere to the glass part for use.

In the embodiment of the present invention, a glass part for protecting a contact image sensor of an image reading device (a device having an image reading function such as a line image scanner, a facsimile equipped with a line image scanner, a multifunction printer, etc.). Alarm means 109 provided in the image reading device to notify that dirt, dust and the like are attached to
However, the present invention is not limited to this. For example, an alarm unit may be provided on a higher-level device (for example, a personal computer: PC) for controlling the image reading device to protect the contact image sensor of the image reading device. It is also possible to configure so as to warn that dirt, dust or the like is attached to the glass part.

As described above, according to the embodiment of the present invention, the image reading apparatus includes the document illuminating means 101 (LED array 212) for illuminating the document, and the condensing means for condensing the reflected light from the document. 102 (lens array 212), image reading means 105 (line image sensor 207) equipped with light detecting means 103 (phototransistor array 211) for detecting condensed light, and document illuminating means 101 and light collecting means 102 are protected. Protective member 104 such as glass
Storage means 1 for storing white correction data based on white correction
08 (white correction data storage RAM 220) and storage means 1
When the white correction data stored in the storage unit 08 exceeds a specified value, the control unit 106 (the CPU 20) that determines that dirt or dust is attached to the protection member 104 and performs an alarm.
1) and the alarm means 109 for notifying that dirt, dust, or the like is attached to the protection member 104, the following effects are obtained.

With the above arrangement, the white correction data of each bit of the output of the contact image sensor (line image sensor) obtained by the white correction performed before the original is read by the image reading device or at the time of calibration exceeds a predetermined value. In this case, the bit data is determined to be caused by dirt or dust attached to the glass part for protecting the contact image sensor, and the user is notified (pointed out) of the dirt part,
By urging the user to clean the contact image sensor protection glass part, an image in which an appropriate SN ratio such as a black streak cannot be obtained because the contact image sensor protection glass part is dirty or dusty as in the related art. Although the user cannot understand the cause and cannot cope with the problem, there is an effect that a good image can be easily obtained with the original SN ratio.

The present invention may be applied to a system composed of a plurality of devices or an apparatus composed of one device. A storage medium storing software program codes for realizing the functions of the above-described embodiments is supplied to a system or an apparatus, and a computer (or CPU or MPU) of the system or the apparatus executes the program code stored in the storage medium. Needless to say, this can also be achieved by executing the reading.

In this case, the program code itself read from the storage medium realizes the functions of the above-described embodiment, and the storage medium storing the program code constitutes the present invention.

As a storage medium for supplying the program code, for example, a floppy disk, hard disk, optical disk, magneto-optical disk, CD-ROM, CD
-R, a magnetic tape, a nonvolatile memory card, a ROM, or the like can be used.

When the computer executes the readout program code, not only the functions of the above-described embodiment are realized, but also the OS and the like running on the computer are actually executed based on the instructions of the program code. It goes without saying that a part or all of the above-described processing is performed, and the functions of the above-described embodiments are realized by the processing.

Further, after the program code read from the storage medium is written into a memory provided in a function expansion board inserted into the computer or a function expansion unit connected to the computer, based on the instruction of the program code, It goes without saying that the CPU included in the function expansion board or the function expansion unit performs part or all of the actual processing, and the processing realizes the functions of the above-described embodiments.

[0043]

As described above, according to the first aspect of the present invention, the document illuminating means for illuminating the document, the light condensing means for condensing light reflected from the document, and the condensing light are detected. What is claimed is: 1. An image reading apparatus comprising: a light detecting unit; and a protection member such as glass for protecting the original illuminating unit and the condensing unit, wherein the storage unit stores white correction data based on white correction; Control means for determining that dirt, dust, and the like are attached to the protection member when the white correction data exceeds a prescribed value, and performing a warning so that dirt, dust, and the like are attached to the protection member; Since there is an alarming means for notifying that the operation is being performed, the following effects can be obtained. The white correction data of each bit of the output of the image sensor including the document illuminating unit, the condensing unit, and the light detecting unit obtained by the white correction performed before the document is read by the image reading device or at the time of the calibration exceeds a predetermined value. In this case, the bit data is determined to be caused by dirt or dust attached to the protection member for protecting the original illuminating means and the light condensing means, and the dirt portion is notified (pointed out) to the user, and the protection member is protected. By urging the user to perform cleaning, as in the past, the protective member becomes dirty or dust adheres, resulting in an image in which an appropriate S / N ratio such as a black stripe cannot be obtained. There is an effect that a good image can be easily obtained at the original S / N ratio even if the image cannot be obtained.

According to the second aspect of the present invention, the specified value of the image reading device is a value obtained by adding a dark side variation of the light emission amount of the document illuminating unit and a dark side variation of the light receiving amount of the light detecting unit. Since this is the maximum value, the following effects are obtained. The white correction data of each bit of the output of the image sensor including the document illuminating unit, the condensing unit, and the light detecting unit obtained by the white correction performed before the reading of the document by the image reading device or during the calibration is a predetermined value, that is, When the maximum value of the sum of the dark-side variation of the light emission amount of the document illuminating unit and the dark-side variation of the light receiving amount of the light detecting unit exceeds the maximum value, the bit data protects the document illuminating unit and the condensing unit. By judging that the protection member is caused by dirt or dust attached to the protection member, the user is notified (pointed out) of the stained portion and urges the user to clean the protection member. An image that cannot be obtained with an appropriate S / N ratio, such as a black stripe, due to dirt or dust attached thereto. There is an effect that so obtained an image.

According to the third aspect of the present invention, the white correction of the image reading apparatus is performed using a member such as a white sheet metal or a calibration sheet before reading the original or at the time of calibration. Play. Before reading the document by the image reading device or at the time of calibration, an image sensor including a document illuminating unit, a condensing unit, and a light detecting unit obtained by white correction performed using a member such as the white sheet metal or the calibration sheet described above. If the white correction data of each bit of the output exceeds a certain specified value, it is determined that the bit data is caused by dirt or dust attached to the protection member that protects the original illuminating means and the condensing means. By notifying (pointing out) the stained portion to the user and prompting the user to clean the protection member, the protection member is stained or dust adheres to obtain an appropriate SN ratio such as a black streak as in the related art. An image that cannot be dealt with and cannot be dealt with by the user without knowing the cause has an effect that a good image can be easily obtained with the original SN ratio.

According to the fourth aspect of the present invention, the alarm means of the image reading device informs the user of the location of the protection member by attaching dirt, dust, or the like, and prompts the user to clean the protection member. It has the following effects. The user can confirm that dirt or dust is attached to the protection member, and can urge the user to start cleaning the protection member. If the member is dirty or dust adheres to it, an image cannot be obtained with an appropriate S / N ratio, such as a black stripe, and the user cannot understand the cause and cannot cope with the problem. There is an effect that a good image can be obtained.

According to the fifth aspect of the present invention, the alarm means of the image reading device informs by voice that the protection member is attached to the protection member with dirt or dust, and that the cleaning of the protection member is prompted. It has the following effects. The user can confirm that dirt or dust is attached to the protection member, and can urge the user to start cleaning the protection member. If the member is dirty or dust adheres to it, an image cannot be obtained with an appropriate S / N ratio, such as a black stripe, and the user cannot understand the cause and cannot cope with the problem. There is an effect that a good image can be obtained.

According to the sixth aspect of the present invention, the image reading device can be connected to a host device such as a computer. Since identification is possible, the following effects are obtained. The user can accurately specify the location of the protection member of the image reading device, such as dirt or dust, on the screen of the host device. An image, such as a black streak, for which an appropriate SN ratio cannot be obtained, and a user who cannot understand the cause and cannot cope with the problem, can easily obtain a good image with the original SN ratio. effective.

According to the seventh aspect of the present invention, since the image reading apparatus can be applied to a line image scanner, a facsimile equipped with a line image scanner, a multifunction printer, and the like, the following effects are obtained. In an apparatus having an image reading function, such as the line image scanner, the facsimile equipped with the line image scanner, and the multifunction printer, the white correction performed before the original is read or at the time of calibration is performed in the same manner as in the first aspect of the invention. When the white correction data of each bit of the output of the image sensor including the original illuminating unit, the condensing unit, and the light detecting unit exceeds a predetermined value, the bit data protects the original illuminating unit and the condensing unit. By judging that the protection member is caused by dirt or dust attached to the protection member, the user is notified (pointed out) of the stained portion and urges the user to clean the protection member. The image becomes dirty or dusty and cannot provide an appropriate S / N ratio, such as black streaks. Those that could not, there is an effect that it becomes possible to obtain more easily satisfactory image in the original SN ratio.

According to the eighth aspect of the present invention, the document illuminating means for illuminating the document, the light condensing means for condensing the reflected light from the document, the light detecting means for detecting the condensed light, A method for determining the contamination of a protection member in an image reading apparatus having a protection member such as a glass for protecting the light condensing means, comprising: a storage step of storing white correction data based on white correction; and a storage step of storing the white correction data based on the white correction. When the white correction data exceeds a specified value, a control step of determining that dirt or dust is attached to the protective member and performing control so as to issue an alarm, and that dirt or dust is attached to the protective member. Since there is a warning step for notifying that the user is present, the following effects are obtained. The white correction data of each bit of the output of the image sensor including the document illuminating unit, the condensing unit, and the light detecting unit obtained by the white correction performed before the document is read by the image reading device or at the time of the calibration exceeds a predetermined value. In this case, the bit data is determined to be caused by dirt or dust attached to the protection member for protecting the original illuminating means and the light condensing means, and the dirt portion is notified (pointed out) to the user, and the protection member is protected. By urging the user to perform cleaning, as in the conventional case, the protective member becomes dirty or dust adheres to the image, resulting in an image in which an appropriate S / N ratio cannot be obtained, such as black streaks. There is an effect that a good image can be easily obtained at the original S / N ratio even if the image cannot be obtained.

According to the ninth aspect of the present invention, the specified value of the method for determining the contamination of the protective member in the image reading device is the variation in the amount of light emitted from the document illuminating unit on the dark side and the variation in the amount of light received by the light detecting unit on the dark side. Since this is the maximum value of the sum of the above, the following effects can be obtained. The white correction data of each bit of the output of the image sensor including the document illuminating unit, the condensing unit, and the light detecting unit obtained by the white correction performed before the reading of the document by the image reading device or during the calibration is a predetermined value, that is, When the maximum value of the sum of the dark-side variation of the light emission amount of the document illuminating unit and the dark-side variation of the light receiving amount of the light detecting unit exceeds the maximum value, the bit data protects the document illuminating unit and the condensing unit. By judging that the protection member is caused by dirt or dust attached to the protection member, the user is notified (pointed out) of the stained portion and urges the user to clean the protection member. An image that cannot be obtained with an appropriate S / N ratio, such as a black stripe, due to dirt or dust attached thereto. There is an effect that so obtained an image.

According to the tenth aspect of the present invention, the white correction of the protective member contamination determining method in the image reading apparatus is performed using a member such as a white sheet metal or a calibration sheet before reading the original or at the time of calibration. The following effects are obtained. Before reading the document by the image reading device or at the time of calibration, an image sensor including a document illuminating unit, a condensing unit, and a light detecting unit obtained by white correction performed using a member such as the white sheet metal or the calibration sheet described above. If the white correction data of each bit of the output exceeds a certain specified value, it is determined that the bit data is caused by dirt or dust attached to the protection member that protects the original illuminating means and the condensing means. By notifying (pointing out) the stained portion to the user and prompting the user to clean the protection member, the protection member is stained or dust adheres to obtain an appropriate SN ratio such as a black streak as in the related art. An image that cannot be dealt with and cannot be dealt with by the user without knowing the cause has an effect that a good image can be easily obtained with the original SN ratio.

According to the eleventh aspect of the present invention, in the warning step of the method for judging the contamination of the protective member in the image reading apparatus, the location where the protective member is attached with dirt or dust and a message prompting the cleaning of the protective member are displayed. The following effects are provided for the notification. The user can confirm that dirt or dust is attached to the protection member, and can urge the user to start cleaning the protection member. If the member is dirty or dust adheres to it, an image cannot be obtained with an appropriate S / N ratio, such as a black stripe, and the user cannot understand the cause and cannot cope with the problem. There is an effect that a good image can be obtained.

According to the twelfth aspect of the present invention, in the warning step of the method for judging the contamination of the protective member in the image reading apparatus, the location where dirt or dust adheres to the protective member and the prompt to clean the protective member are voiced. The following effects are provided for the notification. The user can confirm that dirt or dust is attached to the protection member, and can urge the user to start cleaning the protection member. If the member is dirty or dust adheres to it, an image cannot be obtained with an appropriate S / N ratio, such as a black stripe, and the user cannot understand the cause and cannot cope with the problem. There is an effect that a good image can be obtained.

According to a thirteenth aspect of the present invention, a method for determining the contamination of a protective member in an image reading apparatus is provided. The method includes the steps of: adhering dirt and dust to the protective member on a screen of a host device such as a computer to which the image reading apparatus can be connected; Since the location can be specified, the following effects are obtained. The user can accurately specify the location of the protection member of the image reading device, such as dirt or dust, on the screen of the host device. An image, such as a black streak, for which an appropriate SN ratio cannot be obtained, and a user who cannot understand the cause and cannot cope with the problem, can easily obtain a good image with the original SN ratio. effective.

According to the fourteenth aspect of the present invention, the method for determining the contamination of a protective member in an image reading apparatus can be applied to a line image scanner, a facsimile equipped with a line image scanner, a multifunction printer, and the like. Effect. In an apparatus having an image reading function, such as the line image scanner, the facsimile equipped with the line image scanner, or the multifunction printer, the white image correction is performed by the white correction performed before the original reading or at the time of calibration in the same manner as in the above-mentioned invention. When the white correction data of each bit of the output of the image sensor including the original illuminating unit, the condensing unit, and the light detecting unit exceeds a predetermined value, the bit data protects the original illuminating unit and the condensing unit. By judging that the protection member is caused by dirt or dust attached to the protection member, the user is notified (pointed out) of the stained portion and urges the user to clean the protection member. The image becomes dirty or dusty and cannot provide an appropriate S / N ratio, such as black streaks. Those that could not, there is an effect that it becomes possible to obtain more easily satisfactory image in the original SN ratio.

[Brief description of the drawings]

FIG. 1 is a functional block diagram showing a configuration of a main part of an image reading apparatus according to an embodiment of the present invention and corresponding to the claims.

FIG. 2 is a block diagram showing an electrical configuration of the image reading device according to the embodiment of the present invention.

3A and 3B are explanatory diagrams illustrating an example of a case where a white correction calibration sheet is used at the time of white correction in the image reading device according to the embodiment of the present invention; FIG. FIG. 7B is an explanatory diagram showing dirt / dust and the like, FIG. 7B is an explanatory diagram showing a light / dark level of a contact image sensor output, and FIG. 7C is an explanatory diagram showing a relationship between a contact image sensor output value and a correction amount.

FIG. 4 is a perspective view showing an example in which a white metal sheet for white correction is used at the time of white correction in the image reading apparatus according to the embodiment of the present invention.

FIG. 5 is a flowchart showing a dirt / dust adhesion determining process for a contact image sensor protecting glass part in the image reading apparatus according to the embodiment of the present invention.

FIG. 6 is a flowchart showing a process of determining whether a glass portion for protecting a contact image sensor is dirty or dust adhered in the image reading device according to the embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 101 Document illumination means 102 Condensing means 103 Light detection means 104 Protective member 105 Image reading means 106 Control means 107 Document conveyance means 108 Storage means 109 Alarm means 201 CPU 203 Motor drive circuit 204 Motor 205 Document conveyance roller 207 Line image sensor 211 Photo Transistor array 212 LED array 215 Lens array 220 White correction data storage RAM 221 White correction calibration sheet 222 White correction white sheet metal 223 Dirt / dust

Claims (14)

[Claims] An original illuminating unit for illuminating the original, a condensing unit for condensing light reflected from the original, a light detecting unit for detecting the condensed light, and protecting the original illuminating unit and the condensing unit. An image reading device having a protection member such as glass to be processed, wherein the storage means stores white correction data based on white correction, and the protection is performed when the white correction data stored in the storage means exceeds a prescribed value. Control means for determining that dirt, dust and the like have adhered to the member and performing an alarm, and alarm means for notifying that dirt, dust and the like have adhered to the protective member, Image reading device. 2. The method according to claim 1, wherein the predetermined value is a maximum value obtained by adding a dark-side variation of the light emission amount of the document illuminating unit and a dark-side variation of a light receiving amount of the light detecting unit. 1. The image reading device according to 1. 3. The image reading apparatus according to claim 1, wherein the white correction is performed using a member such as a white sheet metal or a calibration sheet before reading the original or during calibration. 4. The apparatus according to claim 1, wherein the warning unit notifies the user of a location where dirt or dust adheres to the protection member and a message prompting the user to clean the protection member. Image reading device. 5. The alarm device according to claim 1, wherein the alarm unit notifies the user of a location where dirt or dust adheres to the protection member and a message prompting the user to clean the protection member by voice. Image reading device. 6. A connection to a host device such as a computer is possible, and a spot of the protection member, such as dirt or dust, can be specified on a screen of the host device. An image reading device according to any one of claims 1 to 5. 7. The image reading device according to claim 1, wherein the image reading device is applicable to a line image scanner, a facsimile equipped with the line image scanner, a multifunction printer, and the like. 8. An original illuminating means for illuminating an original, a condensing means for condensing reflected light from the original, a light detecting means for detecting the condensed light, and protecting the original illuminating means and the condensing means. A method for determining the contamination of a protective member in an image reading apparatus having a protective member such as glass to be performed, comprising: a storage step of storing white correction data based on white correction; and a white correction data stored in the storage step satisfying a specified value. A control step of determining that dirt, dust, and the like are attached to the protection member when it is exceeded, and performing a warning so as to perform an alarm; and an alarm step of notifying that dirt, dust, and the like are attached to the protection member. And a method for determining the contamination of the protective member in the image reading device. 9. The method according to claim 1, wherein the predetermined value is a maximum value obtained by adding a dark-side variation of a light emission amount of the document illuminating unit and a dark-side variation of a light receiving amount of the light detecting unit. 9. A method for judging protection member contamination in the image reading device according to 8. 10. The apparatus according to claim 8, wherein the white correction is performed using a member such as a white sheet metal or a calibration sheet before reading the original or during calibration.
Or a method for judging protection member dirt in the image reading device according to 9. 11. The method according to claim 8, wherein in the alarming step, a display is provided to inform the user of the location of the protection member to which dirt, dust, or the like is attached, and that the cleaning of the protection member is urged. And a method for determining the contamination of the protective member in the image reading apparatus. 12. The method according to claim 8, wherein in the alarming step, a notification is made by voice of a location where dirt or dust adheres to the protection member and a message prompting the user to clean the protection member. And a method for determining the contamination of the protective member in the image reading apparatus. 13. The protection member according to claim 8, wherein a position where dirt or dust adheres to the protection member can be specified on a screen of a host device such as a computer to which an image reading device can be connected. A method for determining contamination of a protective member in the image reading device according to any one of the above. 14. A protective member stain in the image reading apparatus according to claim 8, wherein the apparatus can be applied to a line image scanner, a facsimile equipped with the line image scanner, a multi-function printer, and the like. Judgment method.