JPH08168002A - Facsimile equipment - Google Patents

Abstract

PURPOSE: To detect dirt on the surface of a sensor before transmission by detecting the dirt on a CIS image sensor from the digital signal of whole data at the time of original reading while referring to white reference data in a white reference memory. CONSTITUTION: A CIS image sensor 6 converts the gradation information of a read original to electric information and converts that electric information to a digital signal by using an A/D converting part 2. Then, a white reference memory 4 stores the white reference data, the white reference data are stored from the converting part 2 into the memory 4, and a white reference memory control part 3 reads the white reference data out of the memory 4. Besides, a deciding part 1 detects dirt on the sensor 6 while referring to the stored data in the memory 4. Further, an image signal is corrected by a white correcting part 7 while referring to the white reference data in the memory, and that output is threshold processed by an image processing part 8. By storing these binary image data into an image memory 13 or using these data, the output to a printing part 9 and a display 15 is controlled by an image memory control part 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a facsimile machine, and more particularly to a facsimile machine suitable for improving image quality.

[0002]

2. Description of the Related Art FIG. 4 shows a conventional example. The conventional example of FIG. 4 is a CIS for converting the grayscale information of a read document into electrical information.
The image sensor 21, an A / D converter 22 for converting electrical information (analog signal) from the CIS image sensor 21 into a digital signal, a white reference memory 24 storing white reference data, and an A / D converter. The white reference data from the white reference memory 2 is stored in the white reference memory 24 and
White reference memory control unit 23 for reading white reference data from No. 4
And referring to the white reference data in the white reference memory 24, A / D
White correction unit 2 that corrects the image signal from the conversion unit 22
7 and an image processing unit 2 for binarizing the output of the white correction unit 27.
8 and the image data from the image processing unit 28 are stored in the image memory 33.
An image memory control unit 30 for controlling the output of the image memory control unit 30 and a control unit 34 for controlling the output of the image memory control unit 30.

Next, the operation of the above conventional example will be described.

(1). White reference data creation process:

.. When a white reference original document without dirt is read by the CIS image sensor 21,
Outputs an analog electric signal corresponding to white data.

[0006] The A / D converter 22 converts the analog signal from the CIS image sensor 21 into a digital signal and outputs it to the white reference memory controller 23.

[0007]. The white reference memory control unit 23 creates white reference data from the signal from the A / D conversion unit 22 and stores it in the white reference memory 24.

(2). Document scanning process:

[0009] When the read document is read by the CIS image sensor 21, the CIS image sensor 21 outputs an analog electric signal corresponding to the light and shade of the document.

[0010]. The A / D converter 22 converts the analog signal from the CIS image sensor 21 into a digital signal and outputs the digital signal to the white corrector 27.

[0011]. The white correction unit 27 refers to the white reference data of the white reference memory 24, and corrects an error in the image signal from the A / D conversion unit 22 due to a characteristic variation of each bit of the CIS image sensor 21.

[0012] The image processing unit 28 binarizes the output of the white correction unit 27 and outputs it to the image memory control unit 30.

.. The image memory control unit 30 includes the image processing unit 2
The image data from 8 is stored in the image memory 33.

When there is a transmission instruction from the control unit 34, the image memory control unit 30 reads the image data from the image memory 33 and outputs it to the CODEC unit 32.

The CODEC section 32 is an image memory control section 3
The image data from 0 is encoded and output to the MODEM 31.

The MODEM 31 modulates the coded signal from the CODEC section 32 and transmits it to the other party via the telephone line.

On the other hand, when there is a copy instruction from the control unit 34, the image memory control unit 30 reads the image data from the image memory 33 and outputs it to the printing unit 29.

The printing unit 29 prints the image data from the image memory control unit 30.

[0019]

However, in the above-mentioned conventional example, since no consideration is given to dirt on the surface of the CIS image sensor, if dirt adheres to the surface of the CIS image sensor, only the dirty portion becomes dark. As a result, a black streak pattern is formed in the vertical direction of the recorded image, and the image has to be retransmitted, and there is an inconvenience that a low quality image is continuously transmitted unless there is a report from the other party.

[0020]

SUMMARY OF THE INVENTION An object of the present invention is to provide a facsimile apparatus which can improve the disadvantages of the conventional example and can detect the dirt on the surface of the CIS image sensor before transmission.

[0021]

Therefore, in the present invention, as a first means, a CIS image sensor for converting grayscale information of a read document into electric information, and electric information from the CIS image sensor are converted into digital signals. A / D
A conversion unit, a white reference memory that stores white reference data for density correction of a read document, and a white correction unit that corrects a digital signal output by the A / D conversion unit based on the white reference data. An image memory control unit for controlling the white-corrected digital signal to be transmitted to a telephone line via a modem. Further, the white correction unit refers to the white reference data of the white reference memory to read an original. The configuration is such that a determination unit for detecting dirt of the CIS image sensor from the digital signal of white data at the time and outputting an ARM signal is additionally provided.

As a second means, a CIS image sensor for converting the grayscale information of the read document into electric information, an A / D converter for converting the electric information from the CIS image sensor into a digital signal, and the read document White reference memory for storing white reference data and black reference data for density correction, and a white correction section for correcting the digital signal output from the A / D conversion section based on the white reference data and the black reference data. And an image memory control unit for controlling the white-corrected digital signal to be transmitted to a telephone line via a modem. The white correction unit refers to the white reference data and the black reference data in the white reference memory. A configuration is adopted in which a determination unit for detecting dirt of the CIS image sensor from the digital signal of white data at the time of reading an original and outputting an ARM signal is provided together. To have.

Further, in addition to the configuration of the first means or the second means, the image memory control unit controls the image memory control unit to output an alarm to the outside when the ARM signal is received, and outputs the alarm. It is preferable to install an alarm indicator. In addition, it is preferable that the image memory control unit is provided with a control unit that controls to output a cleaning message when the ARM signal is received and a character display device that displays the cleaning message.

Further, in addition to the configuration of the first means or the second means, when the ARM signal is received, the image memory control unit generates stain information based on the ARM signal and prints the stain information. It is preferable to provide a control unit for controlling output and a printing unit for printing out the stain information.

The present invention intends to achieve the above-mentioned object by these means.

[0026]

In operation, a clean white reference original is read by a clean CIS image sensor and white reference data is stored in the white reference memory.

Before reading the original, the white reference original is read again and compared with the white reference data stored in the white reference memory in the judging section. When the difference exceeds a predetermined value, the determination unit determines that the CIS image sensor is dirty and notifies the control unit.

When the control section receives the notification of the stain on the CIS image sensor, the control section displays a message prompting cleaning on the display and instructs the print section to print the stain information.

The user can know the dirty portion of the CIS image sensor by looking at the print result.

[0030]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

In the embodiment shown in FIG. 1, a CIS image sensor 6 for converting grayscale information of a read document into electrical information, and a CI
An A / D converter 2 for converting electrical information (analog signal) from the S image sensor 6 into a digital signal, a white reference memory 4 for storing white reference data, and a white reference from the A / D converter 2. A white reference memory control unit 3 for storing the data in the white reference memory 4 and reading the white reference data from the white reference memory 4, and a determination unit for detecting dirt on the CIS image sensor 6 by referring to the stored data in the white reference memory 4. 1 and
A white correction unit 7 for correcting the image signal from the A / D conversion unit 2 with reference to the white reference data in the white reference memory 4, and an image processing unit 8 for binarizing the output of the white correction unit 7. An image memory controller 10 for storing image data from the image processor 8 in the image memory 13 and controlling output such as printing.

Further, in the present embodiment, the printing unit 9 for printing the stain information of the CIS image sensor 6 and the stain signal from the judging unit 1 display a predetermined message on the display 15 and the stain information on the printing unit 9. And a control unit 14 for controlling the image memory control unit 10 so as to print. The display 15 includes a character display section and a voice display section, and outputs an alarm and displays a cleaning message.

Next, the first operation of this embodiment will be described.

(1). White reference data creation process:

.. The white reference document is read by the clean CIS image sensor 6.

The CIS image sensor 6 outputs an analog electric signal corresponding to the white data.

.. The A / D converter 2 converts the analog signal from the CIS image sensor 6 into a digital signal and outputs it to the white reference memory controller 3.

.. The white reference memory control unit 3 creates white reference data from the signal from the A / D conversion unit 2 and stores it in the white reference memory 4.

(2). Document scanning process:

.. When a white reference original document without dirt is read by the CIS image sensor 6, the CIS image sensor 6
Outputs an analog electrical signal corresponding to white data.

.. The A / D conversion unit 2 converts an analog signal from the CIS image sensor 6 into a digital signal and outputs the digital signal to the determination unit 1.

[0042] The determination unit 1 compares the white reference data S1 from the white reference memory 4 with the white data S2 from the A / D conversion unit 2.

That is, as shown in FIG. 2, the difference between the white reference data S1 from the white reference memory 4 and the white data S2 from the A / D converter 2 in the subtractor 1a of the determination unit 1 is 1 pixel. The difference S3 (S3 = S2-S1) is obtained for each output to the comparator 1b.

In the comparator 1b of the judging section 1, as shown in FIG. 2, it is determined whether or not the output S3 of the subtractor 1a is larger than the threshold value T1 preset in the threshold value input section 1c. A comparison is made.

When S3> T1, the white data S
Since 2 means smaller than the white reference data S1, the comparator 1b determines that dust or the like is attached to the CIS image sensor, and sends the ARM signal to the controller 14 as shown in FIG. Output.

[0046] The control unit 14 includes the comparator 1b of the determination unit 1.
When the ARM signal is received from, the display 15 displays a message prompting the cleaning of the CIS image sensor 6.

-1. The white correction unit 7 refers to the white reference data in the white reference memory 4 and corrects the error in the white data S2 from the A / D conversion unit 4 due to the characteristic variation for each bit of the CIS image sensor 6.

-2. The image processing unit 8 binarizes the output of the white correction unit 7 and outputs it to the image memory control unit 10.

-3. The image memory control unit 10 stores the white data from the image processing unit 8 in the image memory 13.

-4. The control unit 14 instructs the image memory control unit 10 to print the white data.

-5. The image memory control unit 10 reads white data from the image memory 13 and outputs it to the printing unit 9. That is, the dirty portion of the CIS image sensor 6 is printed in black.

.. The control unit 14 includes the comparator 1b of the determination unit 1.
If the ARM signal is not received from, the normal document reading process is performed.

-1. When the read original is read by the CIS image sensor 6, the CIS image sensor 6 outputs an analog electric signal corresponding to the light and shade of the original.

-2. The A / D converter 2 converts an analog signal from the CIS image sensor 6 into a digital signal and outputs the digital signal to the white corrector 7.

-3. The white correction unit 7 refers to the white reference data in the white reference memory 4 and corrects the error in the image signal from the A / D conversion unit 2 due to the characteristic variation of each bit of the CIS image sensor 6.

-4. The image processing unit 8 binarizes the output of the white correction unit 7 and outputs it to the image memory control unit 10.

-5. The image memory control unit 10 stores the image data from the image processing unit 8 in the image memory 13.

When there is a transmission instruction from the control unit 14, the image memory control unit 10 reads the image data from the image memory 13 and outputs it to the CODEC unit 12.

The CODEC unit 12 is the image memory control unit 1.
The image data from 0 is encoded and output to the MODEM 11.

The MODEM 11 modulates the coded signal from the CODEC section 12 and sends it to the other party via the telephone line.

On the other hand, when there is a copy instruction from the control unit 14, the image memory control unit 10 reads the image data from the image memory 13 and outputs it to the printing unit 9.

The printing unit 9 prints the image data from the image memory control unit 10.

Next, the second operation of this embodiment will be described.

(1). White reference data creation process:

.. The white reference document is read by the clean CIS image sensor 6.

The CIS image sensor 6 outputs an analog electric signal corresponding to this white data.

.. The A / D converter 2 converts the analog signal from the CIS image sensor 6 into a digital signal and outputs it to the white reference memory controller 3.

.. The white reference memory control unit 3 creates white reference data from the signal from the A / D conversion unit 2 and stores it in the white reference memory 4.

(2). Black reference data creation process:

.. The read original is read by the CIS image sensor 6 with the light source turned off.

The CIS image sensor 6 outputs an analog electric signal corresponding to the black reference data.

.. The A / D converter 2 converts the analog signal from the CIS image sensor 6 into a digital signal and outputs it to the white reference memory controller 3.

[0073] The white reference memory control unit 3 creates black reference data according to the signal from the A / D conversion unit 2 and stores it in the white reference memory 4.

(3). Document scanning process:

.. When a white reference original document without dirt is read by the CIS image sensor 6, the CIS image sensor 6
Outputs an analog electrical signal corresponding to white data.

.. The A / D conversion unit 2 converts an analog signal from the CIS image sensor 6 into a digital signal and outputs the digital signal to the determination unit 1.

.. The determination unit 1 checks the white data S2 from the A / D conversion unit 2 based on the white reference data and the black reference data from the white reference memory 4.

That is, as shown in FIG. 3, the white reference data from the white reference memory 4 is stored in the first bit shift unit 1d of the determination unit 1, and the black reference data from the white reference memory 4 is stored in the determination unit 1. It is input to the second bit shift unit 1e.

The first bit shift unit 1d and the second bit shift unit 1e shift rightward by one bit. That is, it is halved numerically.

The adder 1f includes a first bit shift unit 1d
Output S1A and the output S1B of the second bit shift unit 1e
And are added, and the addition result T2 (T2 = (white reference data + black reference data) / 2) is output to the comparator 1g. This T2
Is an intermediate value between the white reference value and the black reference value.

In the comparator 1g of the judging section 1, as shown in FIG. 3, T2 and the white data S2 from the A / D converting section 2 are compared pixel by pixel, and when S2 <T2, the ARM signal is output. Is output to the control unit 14.

.. The control unit 14 includes the comparator 1g of the determination unit 1.
When the ARM signal is received from, the display 15 displays a message prompting the cleaning of the CIS image sensor 6.

-1. The white correction unit 7 refers to the white reference data of the white reference memory 4 and corrects the error in the white data S2 from the A / D conversion unit 2 due to the characteristic variation of each bit of the CIS image sensor 6.

-2. The image processing unit 8 binarizes the output of the white correction unit 7 and outputs it to the image memory control unit 10.

-3. The image memory control unit 10 stores the white data from the image processing unit 8 in the image memory 13.

-4. The control unit 14 instructs the image memory control unit 10 to print this white data.

-5. The image memory control unit 10 reads white data from the image memory 13 and outputs it to the printing unit 9. That is, the dirty portion of the CIS image sensor 6 is printed in black.

.. The control unit 14 includes the comparator 1b of the determination unit 1.
If the ARM signal is not received from, the normal document reading process is performed.

-1. When the read original is read by the CIS image sensor 6, the CIS image sensor 6 outputs an analog electric signal corresponding to the light and shade of the original.

-2. The A / D converter 2 converts an analog signal from the CIS image sensor 6 into a digital signal and outputs the digital signal to the white corrector 7.

-3. The white correction unit 7 refers to the white reference data in the white reference memory 4 and corrects the error in the image signal from the A / D conversion unit 2 due to the characteristic variation of each bit of the CIS image sensor 6.

-4. The image processing unit 8 binarizes the output of the white correction unit 7 and outputs it to the image memory control unit 10.

-5. The image memory control unit 10 stores the image data from the image processing unit 8 in the image memory 13.

When there is a transmission instruction from the control unit 14, the image memory control unit 10 reads the image data from the image memory 13 and outputs it to the CODEC unit 12.

The CODEC unit 12 is the image memory control unit 1.
The image data from 0 is encoded and output to the MODEM 11.

The MODEM 11 modulates the coded signal from the CODEC section 12 and sends it to the other party via the telephone line.

On the other hand, when there is a copy instruction from the control unit 14, the image memory control unit 10 reads the image data from the image memory 13 and outputs it to the printing unit 9.

The printing unit 9 prints the image data from the image memory control unit 10.

[0099]

Since the present invention is constructed and functions as described above, according to this, the original read by the CIS image sensor is compared with the white reference data stored in the white reference memory in the determination section, When the difference exceeds a predetermined value, the determination unit determines that the CIS image sensor is dirty and notifies the control unit, so that the CIS image sensor can be detected before the transmission. Therefore, it is possible to prevent the transmission of a document having black streaks due to the stain of the CIS image sensor, and to provide an excellent facsimile device which has never been necessary, in which it is not necessary to confirm the quality and retransmit the document to the destination. be able to.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of the present invention.

FIG. 2 is a first explanatory diagram for explaining a determination unit in FIG.

FIG. 3 is a second explanatory diagram for explaining a determination unit in FIG.

FIG. 4 is a configuration diagram showing a conventional example.

[Explanation of symbols]

 1 determination unit 1a subtractor 1b comparator 1c threshold input unit 1d first bit shift unit 1e second bit shift unit 1f adder 1g comparator 2 A / D conversion unit 3 white reference memory control unit 4 white reference Memory 5 Input / output buffer 6 CIS image sensor 7 White correction unit 8 Image processing unit 9 Printing unit 10 Image memory control unit 11 MODEM (modem) 12 CODEC unit 13 Image memory 14 Control unit 15 Display

Claims (5)

[Claims] 1. A CIS image sensor for converting density information of a read document into electric information, an A / D converter for converting electric information from the CIS image sensor into a digital signal, and a density correction unit for correcting the density of the read document. A white reference memory that stores white reference data, a white correction unit that corrects the digital signal output by the A / D conversion unit based on the white reference data, and the white-corrected digital signal via a modem. In a facsimile apparatus provided with an image memory control unit for controlling transmission to a telephone line, the white correction unit refers to white reference data in the white reference memory, and outputs the digital signal of the white data at the time of reading an original from the CIS. A facsimile machine characterized by being provided with a judging section for detecting dirt of an image sensor and outputting an ARM signal. 2. A CIS image sensor for converting density information of a read document into electric information, an A / D converter for converting electric information from the CIS image sensor into a digital signal, and a density correction unit for correcting density of the read document. A white reference memory that stores white reference data and black reference data, a white correction unit that corrects a digital signal output by the A / D conversion unit based on the white reference data and black reference data, and the white correction. In a facsimile apparatus including an image memory control unit that controls to transmit the digital signal to a telephone line via a modem, the white correction unit refers to white reference data and black reference data in the white reference memory. A determination unit for detecting dirt of the CIS image sensor from the digital signal of white data at the time of reading an original and outputting an ARM signal is additionally provided. Facsimile apparatus according to symptoms. 3. The image memory control section is provided with a control section for controlling to output an alarm to the outside when the ARM signal is received, and an alarm indicator for uttering the alarm. The facsimile apparatus according to claim 1 or 2. 4. The image memory control section is provided with a control section for controlling a cleaning message to be output when the ARM signal is received, and a character display for displaying the cleaning message. The facsimile apparatus according to claim 1 or 2. 5. The control unit for controlling the image memory control unit to generate stain information based on the ARM signal when the ARM signal is received and to print out the stain information, and the stain information. 3. The facsimile apparatus according to claim 1, further comprising a printing unit for printing and outputting.