JP2001148765A - Light emitting element drive device and image reader - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light emitting element drive device and an image reader which turn on and off light emitting elements arranged in array and adjust the quantity of light of the light emitting elements or light emitting element groups. SOLUTION: When a document is mounted and the start of read is indicated, facsimile equipment turns on an LED array by an LED illumination control part to read a white standard plate and collect shading correction data, and detects whether or not there is an abnormal pixel according to the shading correction data. Once an abnormal pixel is detected, the pixel address of the detected abnormal pixel is stored and the abnormal pixel detection is completed as to all the shading correction data; when the abnormal pixel is detected, it is considered that some stain or foreign matter sticks on an optical system, so a message showing that the abnormal pixel is detected is displayed on a display and the LED at the position corresponding to the pixel position of the detected abnormal pixel of the LED array is turned on or blinked (steps S101 to S108).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light emitting device driving device and an image reading device, and more particularly, to a method of lighting / flashing a plurality of light emitting devices arranged in a row for each light emitting device or a plurality of light emitting devices. The present invention relates to a light emitting element driving device and an image reading device that control light emission conditions such as light emission amount adjustment.

[0002]

2. Description of the Related Art In general, an image reading apparatus generally uses an LED (light-emitting diode).
A light emitting element array such as a t Emitting Diode (Array) is used as a light source. The light source irradiates the document with light, and the reflected light from the document is incident on a photoelectric conversion element such as a CCD (Charge Coupled Device). Is converted into an electric signal to read the image of the original.

In an image reading apparatus, it is important that the amount of light of an LED used as a light source is appropriate in reading a document image in a good state.

Therefore, conventionally, a light emission amount varying means for changing a light emission amount of a light source to be controlled, a light emission amount detecting means for detecting a light emission amount of the light source, and a light emission amount detecting means for detecting the light emission amount. There has been proposed a light source control circuit including a light emission amount control means for controlling the light emission amount varying means so that the light emission amount approaches a predetermined light emission amount set in advance (see Japanese Patent Application Laid-Open No. 7-231376). .

Further, in the image reading apparatus, fluctuations in the amount of light emitted from the LED as a light source with the passage of time, fluctuations due to a rise in temperature, and fluctuations in the reading density due to fluctuations in the sensitivity of each pixel of the photoelectric conversion unit are caused. Conventionally, in order to prevent the image quality from being deteriorated, a white reference member is scanned by a reading unit before reading an image of a document to obtain shading correction data, and a document is scanned based on the shading correction data. Has been performed.

That is, in the conventional image reading apparatus, for example, as shown in FIG. 7, a white reference plate 10 disposed on the back of a reading position of a document 102 from an LED 101 as a light source.
3 is irradiated with light, and the reflected light is applied to the image sensor 104.
A / D after photoelectric conversion by the operational amplifier 105 and amplification by the operational amplifier 105
The data quantized by the converter 106 is stored as shading correction data in a line buffer 108 via a shading correction circuit 107.

After acquiring the shading correction data, the original 102 is read. In the reading process of the document 102, the document 102 is irradiated with light from the LED 101, the reflected light from the document 102 is photoelectrically converted by the image sensor 104, and converted into an analog image signal.
After the signal is amplified by the operational amplifier 105 at a predetermined amplification rate and the impedance is reduced, the A / D converter 10
In step 6, quantization is performed based on a predetermined reference level. The image data of the document digitally converted by the A / D converter 106 is
The line buffer 108 in the shading correction circuit 107
The shading correction superimposed on the image signal mainly due to the optical system is removed by shading correction based on the shading correction data stored in the digital image processing unit 109, and then stored in the line buffer 108 by the digital image processing unit 109. Various image processing is performed with reference to the various data.

As a conventional image reading apparatus for performing such shading correction, for example, in an image input in which image data optically read by a line sensor can be input, the image data is read optically from the reading position by the line sensor. Storage means capable of at least temporarily storing the obtained data for one line for shading correction, and control means for controlling storage of the data for one line in the storage means and reading from the storage means There has been proposed an image input device comprising: a unit for displaying and / or recording the one line of data read from the storage unit via the control unit (Japanese Patent Application Laid-Open No. H5-205).
No. 75853).

That is, the image input device stores and displays or records shading correction data for one line, and can determine the light amount of the reading light source, the black level of the line sensor, and the like in pixel units. I have to.

Conventionally, at the start of reading a document, a white pressure plate indicating a white reference is read, the read data is stored, and shading correction is performed on the basis of the read data to equalize the output in the main scanning direction. As a facsimile apparatus having a system, a facsimile apparatus has been proposed which is provided with a system control means for reading a white pressure plate at regular intervals and outputting the read data to recording paper (see Japanese Patent Application Laid-Open No. Hei 7-18447).

That is, this facsimile apparatus reads a white pressure plate at regular time intervals and records and outputs read data on a recording paper so that the white pressure plate, the contact glass, the dirt on the mirror, and the abnormality in the reduction optical system can be detected. I have to.

Further, conventionally, in an image processing apparatus having a plurality of processing routes for processing image data, changing means for changing the processing route, generating predetermined test image data, and transferring the test image data to the processing route. Supply means, supply means, control means for changing the processing route by the change means, and flow of the test image data generated by the generation means to the plurality of processing routes, There has been proposed an image processing apparatus including a determination unit that determines a failure location based on the test image data, and a transmission unit that transmits the determination result of the determination unit to an external device (Japanese Patent Application Laid-Open No. H10-1998).
No. 70627).

That is, the image processing apparatus can specify a failure location in the image processing circuit and notify the external device.

[0014]

However, in the conventional LED array, as described in Japanese Patent Application Laid-Open No. 7-231376, the amount of emitted light is controlled in units of blocks. However, there is a problem that the lighting control cannot be performed and the usability is poor.

Further, in the conventional image reading apparatus, it is necessary to improve the image reading system in order for the operator to appropriately recognize the abnormality, particularly, the abnormal location.

That is, in the image input device described in JP-A-5-75853, one line of shading correction data is stored and displayed or recorded. Also, in the image input device described in JP-A-7-184407. In the facsimile apparatus described above, the white pressure plate is read at regular time intervals and the read data is recorded and output on the recording paper.Therefore, the operator only needs to display or record and output the shading correction data and the read data of the white pressure plate. An abnormality in the image reading system could not be properly recognized, and there was a need for improvement.

Further, in the image processing apparatus described in Japanese Patent Application Laid-Open No. 10-70627, a failure point in the image processing circuit is specified and notified to an external device such as a service center, so that an operator can promptly operate. However, it was not possible to recognize the abnormality of the image processing apparatus, and there was a need for improvement.

Therefore, according to the first aspect of the present invention, a light emitting element array in which a plurality of light emitting elements are arranged in a row is controlled to be turned on and off for each light emitting element and / or for each of the plurality of light emitting elements. Perform precise lighting control according to the application,
It is an object of the present invention to provide a light-emitting element driving device with good usability.

According to a second aspect of the present invention, light from a light emitting element array in which a plurality of light emitting elements are arranged in a row is irradiated on a document located on a document reading surface, and an image of the document is read by the reflected light. At this time, the control means controls the lighting / non-lighting and / or the light emission amount as the lighting condition of the light emitting element array via the drive control means for each light emitting element and / or for each of the plurality of light emitting elements, so that It is an object of the present invention to provide an image reading apparatus capable of precisely controlling a light emitting element array as a light source to turn on / off and controlling the amount of emitted light in accordance with the reading state of the light source, thereby improving the image quality of a read image.

According to a third aspect of the present invention, when a white reference member is read before reading a document to obtain white reference data and perform shading correction of an optical system, the document reading surface is determined based on the white reference data. When the dirt is detected, the light emitting element or the plurality of light emitting elements at the position corresponding to the dirt is turned on, and the dirt is notified to allow an operator or the like to appropriately recognize the dirt position on the document reading surface, thereby improving work efficiency. It is an object of the present invention to provide an image reading device capable of improving the image reading.

According to a fourth aspect of the present invention, when a stain on the original reading surface is detected based on the white reference data, the light emitting element or a plurality of light emitting elements at a position corresponding to the stain are blinked at a predetermined cycle, and the stain is detected. An object of the present invention is to provide an image reading apparatus that allows an operator or the like to more appropriately recognize a dirt position on a document reading surface, thereby further improving work efficiency.

According to a fifth aspect of the present invention, when a white reference member is read before reading a document to obtain white reference data and perform shading correction of an optical system, a light emitting element is provided based on the white reference data. By adjusting the amount of light emitted from the light emitting elements of the array for each light emitting element or a plurality of light emitting elements, the amount of light emitted from the light emitting element array as a light source is made more appropriate and uniform, and the image quality of the read image is further improved. It is an object to provide an image reading device that can be improved.

According to a sixth aspect of the present invention, when the amount of emitted light exceeds a predetermined reference amount of emitted light, a predetermined warning is notified and output, whereby the abnormality of the image reading apparatus is promptly recognized and the maintenance performance is improved. It is an object of the present invention to provide an image reading apparatus capable of causing the reading.

According to a seventh aspect of the present invention, by changing the range of the light emitting elements to emit light in the light emitting elements of the light emitting element array in accordance with the document width detected by the document size detecting means, unnecessary areas outside the document range are changed. It is an object of the present invention to provide an image reading apparatus in which a light emitting element for irradiating an unnecessary area is turned off to reduce unnecessary power consumption.

The invention according to claim 8 is characterized in that, among the light emitting elements of the light emitting element array, a light emitting element in a range that irradiates a range wider than the detected document width by a predetermined width emits light, so that the document is skewed. Another object of the present invention is to provide an image reading apparatus which can irradiate a document with necessary light from a light emitting element array and stably read the document.

[0026]

According to a first aspect of the present invention, there is provided a light-emitting element driving apparatus, comprising: a light-emitting element array in which a plurality of light-emitting elements are arranged in a row; In the light emitting element driving device comprising:
The drive control means achieves the above object by controlling lighting and non-lighting of the light emitting element array for each light emitting element and / or for each of a plurality of light emitting elements.

According to the above configuration, the light emitting element array in which a plurality of light emitting elements are arranged in a row is controlled to be turned on and off for each light emitting element and / or for each of the plurality of light emitting elements. Lighting control can be performed, and the usability of the light emitting element driving device can be improved.

The image reading apparatus according to the second aspect of the present invention irradiates a document located on the document reading surface with light from a light emitting element array in which a plurality of light emitting elements driven by drive control means are arranged in a row. In the image reading apparatus that reads the image of the document by the reflected light, the drive control unit controls the lighting / non-lighting and / or light emission amount as the lighting condition of the light emitting element array for each of the light emitting elements. The above object is achieved by providing control means for controlling each of the plurality of light emitting elements.

According to the above arrangement, when the light from the light emitting element array in which a plurality of light emitting elements are arranged in a row is irradiated on the original located on the original reading surface and the reflected light is used to read the image of the original. The lighting / non-lighting and / or lighting conditions of the light emitting element array are controlled by the control means via the drive control means.
Alternatively, since the light emission amount is controlled for each light emitting element and / or for each of a plurality of light emitting elements, it is possible to precisely turn on / off the light emitting element array as a light source and control the light emission amount according to the reading state of the document. As a result, the image quality of the read image can be improved.

In this case, for example, as set forth in claim 3, the image reading apparatus further includes a predetermined white reference member for providing white reference data. An image reading apparatus that performs reading, acquires the white reference data, and performs shading correction of an optical system, wherein the control unit detects the dirt on the document reading surface based on the white reference data and performs the driving. The dirt may be notified by turning on the light emitting element or the plurality of light emitting elements at a position corresponding to the dirt via the control means.

According to the above arrangement, before reading the original,
When the white reference member is read and white reference data is acquired and shading correction of the optical system is performed, if a stain on the document reading surface is detected based on the white reference data, the light emitting element or a plurality of light emitting elements at a position corresponding to the stain are detected. The dirt is notified by turning on the light emitting element, so that the operator or the like can appropriately recognize the dirt position on the document reading surface, and the work efficiency can be improved.

Further, for example, as described in claim 4, when the control means detects a stain on the original reading surface based on the white reference data, the control means responds to the stain via the drive control means. The light emitting element or the plurality of light emitting elements at the position to be blinked at a predetermined cycle may be notified of the dirt.

According to the above arrangement, when the dirt on the original reading surface is detected based on the white reference data, the light emitting element or the plurality of light emitting elements at the position corresponding to the dirt is blinked at a predetermined cycle to notify the dirt. Therefore, the operator or the like can more appropriately recognize the dirt position on the document reading surface, and the working efficiency can be further improved.

Further, for example, as set forth in claim 5, the image reading apparatus further includes a predetermined white reference member for providing white reference data.
An image reading apparatus that reads the white reference member to acquire the white reference data and performs shading correction of an optical system, wherein the control unit is configured to perform the shading correction based on the white reference data via the drive control unit. The light emission amount of the light emitting elements of the light emitting element array may be adjusted for each light emitting element or each of the plurality of light emitting elements.

According to the above arrangement, before reading the original,
When the white reference member is read to obtain white reference data and perform shading correction of the optical system, based on the white reference data, the light emission amount of the light emitting element of the light emitting element array is determined for each light emitting element or each of a plurality of light emitting elements. To adjust
The amount of light emitted from the light emitting element array as a light source can be made more appropriate and uniform, and the image quality of a read image can be further improved.

Further, for example, the control means may output a predetermined warning when the light emission amount exceeds a preset reference light emission amount.

According to the above configuration, when the amount of emitted light exceeds a predetermined reference amount of emitted light, a predetermined warning is notified and output, so that the abnormality of the image reading apparatus can be promptly recognized and the maintenance performance is improved. Can be done.

Further, for example, as set forth in claim 7, the image reading apparatus further comprises a document size detecting means for detecting at least a width of the document on the document reading surface, and the control means comprises: The range of the light emitting elements to emit light among the light emitting elements of the light emitting element array may be changed via the drive control means according to the document width detected by the document size detecting means.

According to the above arrangement, the range of the light emitting elements to be emitted from the light emitting elements of the light emitting element array is changed in accordance with the document width detected by the document size detecting means. The light-emitting element to be irradiated can be turned off, and wasteful power consumption can be reduced.

For example, as set forth in claim 8, the control means controls the drive control means to control the light-emitting elements of the light-emitting element array by a predetermined width from the detected document width. The light emitting element may emit light in a range that irradiates a wide range.

According to the above configuration, of the light emitting elements of the light emitting element array, the light emitting elements in a range that irradiates a range wider than the detected document width by a predetermined width are made to emit light. The document can be irradiated with necessary light from the element array, and the document can be read stably.

[0042]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. It should be noted that the embodiments described below are preferred embodiments of the present invention, and therefore, various technically preferable limitations are added. However, the scope of the present invention is not limited to the following description. The embodiments are not limited to these embodiments unless otherwise specified.

FIGS. 1 to 3 show a first embodiment of a light emitting element driving device and an image reading device according to the present invention.
FIG. 1 is a block diagram of a facsimile apparatus 1 to which a first embodiment of a light emitting element driving device and an image reading device according to the present invention is applied.

In FIG. 1, the facsimile apparatus 1 includes a control unit 2, a system memory 3, a parameter memory 4, a scanner 5, a plotter 6, a network control unit 7, a modem 8, an image storage unit 9, an encoding / decoding unit 10.
And an operation panel 11 and the like, and the above-described units are connected by a system bus 12.

The system memory 3 has a ROM (Read Only)
Memory) and a random access memory (RAM), and stores various programs such as a basic processing program as the facsimile machine 1, an abnormal pixel detection processing program, a shading management processing program, and an LED array drive control processing program. It stores system data necessary to execute each process,
Further, it is used as a work memory of the control unit 2.

The control unit (control means) 2 controls each unit of the facsimile apparatus 1 using the system memory 3 as a work memory based on a program in the system memory 3 to perform basic processing as the facsimile apparatus 1. At the same time, it executes an abnormal pixel detection process, a shading management control process, and an LED array drive control process, which will be described later.

The parameter memory 4 stores various parameter information necessary for facsimile communication.

As shown in FIG. 2, the scanner (image reading device) 5 includes an LED (Light Emitting Diode) array (light emitting) as a light source for irradiating the original 21 conveyed on the contact glass by a conveying roller (not shown). Element array) 22, LEDs for controlling lighting of LEDs (light emitting elements)
Lighting control unit (drive control unit) 23, white reference plate (white reference member) 24 for correcting shading distortion caused by the optical system, image sensor 25, operational amplifier 26, A / A
A D converter 27, a shading correction unit 28, a line buffer 29, a digital image processing unit 30, an abnormal pixel detection unit 31, and the like are provided.
The digital image processing unit 30 is connected to the control unit 2 via the system bus 12.

When scanning the white reference plate 24, the LED
The light from the array 22 is applied to a white reference plate 24 through a contact glass (not shown), and the light reflected by the white reference plate 24 forms an image on an image sensor 25 at a predetermined reduction rate via an optical system. Is done. When the original 21 is scanned, light from the LED array 22 irradiates the original 21 conveyed over the contact glass through the contact glass, and the light reflected by the original 21 passes through a predetermined optical system. Is formed on the image sensor 25 at the reduction ratio of.

The image sensor 25 converts the formed optical information into an electric signal and outputs it to an operational amplifier 26. The operational amplifier 26 amplifies the analog image signal input from the image sensor 25 at a predetermined magnification. At the same time, the impedance is converted and output to the A / D converter 27.

A / D (Analog to Digita) converter 27
Quantizes an image signal input from the operational amplifier 26 to a predetermined number of bits with reference to a predetermined reference value, for example, based on a peak value input from the image sensor 25 via the operational amplifier 26, Shading correction unit 2
8 is output.

The line buffer 29 stores, as shading correction data, one line of image data output from the A / D converter 27 when the white reference plate 24 is scanned.
It is referred to in shading correction by the shading correction unit 28 and image processing in the digital image processing unit 30.

The shading correction circuit 28 includes the control unit 2
Under the control of, the shading correction for correcting the shading distortion caused by the characteristics of the LED array 22 and the optical system in the image data input from the A / D converter 27 while referring to the shading correction data stored in the line buffer 29. Processing is performed and output to the digital image processing unit 30.

The digital image processing unit 30 operates under the control of the control unit 2 and refers to the shading correction data stored in the line buffer 29 or uses the line buffer 29 to generate a signal from the shading correction unit 28. The input image data is binarized, subjected to halftone processing, and various image processing is performed.

Therefore, when the scanner 5 scans the white reference plate 24 to obtain shading correction data for shading correction, the image sensor 25
The image signal converted into the electric signal is amplified by the operational amplifier 26 and converted into a digital signal by the A / D converter 27, and then stored as shading correction data in the line buffer 29 via the shading correction unit 28.

Thereafter, when scanning the original 21, the image signal converted into an electric signal by the image sensor 25 is amplified by the operational amplifier 26, digitally converted by the A / D converter 27, and then shaded by the line buffer 29. With reference to the correction data, shading correction is performed by the shading correction unit 28, and various image processing is performed by the digital image processing unit 30, and then output.

The abnormal pixel detector 31 is connected to the shading corrector 28 and the line buffer 29, and detects the presence or absence of an abnormal pixel based on the shading correction data.
The detection result is output to the control unit 2.

The LED array 22 has a plurality of LEDs arranged in a line (row) sufficient to irradiate light on at least the original 21 having the maximum size.

The LED lighting control unit 23 operates under the control of the control unit 2 to control lighting / non-lighting and subtle brightness control (light emission) of each LED of the LED array 22 one by one or in units of plural blocks. Light amount control).

Although not shown, the scanner 5 usually has an ADF (automatic document feeder),
Feeds the set plurality of documents 21 one by one to the contact glass, that is, the reading position.

Referring again to FIG. 1, as the plotter 6, for example, a thermal recording device using a thermal element or an electrophotographic recording device is used.
Records the received image data, the image of the document read by the scanner 5 and the necessary report on a recording sheet at a predetermined resolution.

The network control unit 7
The network control unit 7 is connected to a line (for example, a telephone line). The network control unit 7 operates under the control of the control unit 2 to automatically receive an incoming call from a line and perform an automatic call processing to the line.
A facsimile communication procedure is executed by exchanging a facsimile control signal with a partner facsimile apparatus, setting communication functions and exchanging various control information.

The modem 8 is for realizing a G3 facsimile modem function. The modem 8 is a low-speed modem function (V.21) for exchanging a transmission procedure signal with a partner facsimile apparatus and mainly for exchanging image data. High-speed modem function (V.34 modem, V.29 modem,
V. 27ter modem etc.).

The image storage unit 9 is, for example, a large-capacity RAM.
(Random Access Memory) or a hard disk device, and mainly stores image data. That is,
The image storage unit 9 stores image data for transmission read by the scanner 5 and image data received, and is read out at a predetermined time under the control of the control unit 2 and used for transmission processing, recording processing, and the like. Is done.

The encoding / decoding section 10 shortens the transmission time of the image data and increases the efficiency of the storage in the image storage section 9, and compresses (encodes) the image data at the time of transmission.
At the time of reception, the encoded image data is reproduced (decoded) into original image data.

The operation panel 11 includes various operation keys such as a numeric keypad, a start key, a stop key, and a function key, and also includes a display (for example, a liquid crystal display). Is entered. Further, the display of the operation panel 11 displays the content of a command input from the operation keys and various information notified from the facsimile machine 1 to the operator.

In the facsimile machine 1, data exchange between the respective units is performed via the system bus 12, and data exchange between the network control unit 7 and the modem 8 is directly performed.

Next, the operation of this embodiment will be described. The facsimile apparatus 1 obtains shading correction data by reading the white reference plate 24 before reading the document 21. The facsimile apparatus 1 determines whether or not there is an abnormal pixel in the shading correction data. The feature is that the LED of the LED array 22 at a position corresponding to the position where the abnormal pixel is present is lit or blinked individually or in units of a plurality to notify the abnormal position.

That is, in the facsimile machine 1, as shown in FIG. 3, when a plurality of documents 21 are placed on a document table (not shown), a start key on the operation panel 11 is pressed, and a reading start instruction is issued. (Step S101) First, the white reference plate 24 is read to obtain shading correction data. That is, in the facsimile apparatus 1, the white reference plate 24 is disposed at the reading position on the surface of the contact glass of the image sensor 25, and the control unit 2
Causes the LED lighting control unit 23 to light the LED array 22 as a light source (step S102), and causes the image sensor 25 to read the white reference plate 24. At this time,
The control unit 2 turns on the LEDs of the LED array 22 at a preset light amount or at the light amount set in the previous light amount adjustment processing via the LED lighting control unit 23.

The image sensor 25 converts the optical information from the white reference plate 24 into an electric signal and outputs the electric signal to the operational amplifier 26. The operational amplifier 26 converts the analog image signal input from the image sensor 25 to a predetermined magnification. , And impedance-converted and output to the A / D converter 27. The A / D converter 27 quantizes the image signal input from the operational amplifier 26 into a predetermined number of bits on the basis of a predetermined reference value, and generates shading correction data via the shading correction unit 28 via the line buffer 29 and the line buffer 29. The data is output to the abnormal pixel detector 31 and stored in the line buffer 29 to collect shading correction data (step S103).

When the shading correction data is collected,
The control unit 2 provides the abnormal pixel detection unit 31 with the line buffer 2
The presence or absence of an abnormal pixel is detected based on the shading correction data stored in No. 9 and the detection result is output to the control unit 2 (Step S104). The abnormal pixel detection unit 31 calculates, for example, a level difference between the pixel of interest and pixels before and after the pixel of interest,
If the level difference is equal to or greater than a predetermined value, the target pixel is recognized as an abnormal pixel. The detection of an abnormal pixel by the abnormal pixel detection unit 31 may be performed based on the shading correction data input from the shading correction unit 28 before storing the shading correction data in the line buffer 29.

The abnormal pixel detecting section 31 determines in step S104
When an abnormal pixel is detected, the pixel address of the detected abnormal pixel is stored (step S105), and the detection of the abnormal pixel is completed for all the shading correction data, that is, the collection of all the shading correction data is completed. It is checked whether it has been performed (step S106).

If it is determined in step S106 that the collection of all the shading correction data has not been completed, the control unit 2 returns to step S103 and sequentially collects the next shading correction data. The presence or absence of a pixel is detected (steps S103 and S104). If there is no abnormal pixel in step S104, the process proceeds to step S106 to check whether or not all shading correction data has been collected (step S10).
6).

The above processing is sequentially performed, and step S106
When the collection of all the shading correction data is completed, the control unit 2 checks whether or not the abnormal pixel detection unit 31 has detected the abnormal pixel (step S107). Since some dirt or foreign matter may be attached, the display of the operation panel 11 displays that the abnormal pixel is detected in the shading correction data, and controls the LED lighting control unit 23 to detect the detection of the LED array 22. The LED at the position corresponding to the pixel position of the abnormal pixel is turned on or blinked in a predetermined cycle individually or in a plurality of units, and the process is terminated (step S108). At this time, the control unit 2
For example, "Open the cover of the scanner unit and clean the area where the lamp is lit."
1 is displayed on the display.

If no abnormal pixel is detected in step S107, the control section 2 terminates the processing without displaying on the display and turning on / off the LED, and returns to the normal reading operation of the original 21. The process proceeds to read the image of the document 21.

As described above, the facsimile apparatus 1 of the present embodiment controls the lighting and non-lighting of the LED array 22 in which a plurality of LEDs are arranged in a row for each LED and / or for each LED. .

Therefore, precise lighting control can be performed according to the use of the LED array 22, and the usability of the light emitting element driving device can be improved.

Further, the facsimile apparatus 1 of the present embodiment
Is an LED array 22 in which a plurality of LEDs are arranged in a row.
Irradiates the original 21 positioned on the original reading surface with light from
When reading the image of the original 21 by the reflected light, the control unit 2 controls the lighting / non-lighting and / or the light emission amount as the lighting condition of the LED array 22 via the LED lighting control unit 23 for each LED and / or Control is performed for each of a plurality of LEDs.

Therefore, the LED array 22 as the light source can be precisely turned on / off and the amount of emitted light can be controlled in accordance with the reading state of the document, and the image quality of the read image can be improved.

Further, the facsimile apparatus 1 of the present embodiment reads the white reference plate 24 before reading the original 21 to obtain shading correction data (white reference data).
When performing the shading correction of the optical system to obtain the dirt on the original reading surface based on the shading correction data, the LED or the plurality of LEDs at the position corresponding to the dirt is turned on to notify the dirt. ing.

Accordingly, it is possible for an operator or the like to appropriately recognize the dirt position on the document reading surface, and it is possible to improve work efficiency.

Further, the facsimile apparatus 1 of the present embodiment
When the dirt on the document reading surface is detected based on the shading correction data, the LED or a plurality of LEDs at a position corresponding to the dirt is blinked at a predetermined cycle to notify the dirt.

Therefore, the operator can more appropriately recognize the dirt position on the document reading surface, and the working efficiency can be further improved.

FIG. 4 is a diagram showing a second embodiment of the light emitting element driving device and the image reading device of the present invention. In this embodiment, each LED of the LED array is based on the collected shading correction data. Are controlled.

This embodiment is applied to a facsimile machine similar to that of the first embodiment.
In the description of the present embodiment, the description will be made using the reference numerals used in the description of the first embodiment as they are.

In the facsimile apparatus 1 of the present embodiment, the LED array 22 which is the light source of the scanner 5 has the first
The driving is controlled by the LED lighting control unit 23 as in the embodiment described above. In the facsimile apparatus 1 according to the present embodiment, in particular, the plurality of LEDs of the LED array 22 are individually turned on or in a plurality of units. The non-lighting control is performed, and the light emission amount is controlled.

That is, in the facsimile apparatus 1, as shown in FIG. 4, when a plurality of documents 21 are placed on a document table (not shown), a start key on the operation panel 11 is pressed, and an instruction to start reading is issued. (Step S201) First, the LED array 22, which is a light source, is turned on with a preset light amount or with the light amount set in the previous light amount adjustment processing, and the white reference plate 24 is read to perform shading correction. Data is acquired, and an output level determination reference value THp for evaluating the output level of the shading correction data at this time and a uniformity determination reference for determining the uniformity of the output level of one line of the shading correction data. The value THu is set (step S20).
2).

The facsimile apparatus 1 converts the reflected light of the light emitted from the LED array 22 to the white reference plate 24 into an electric signal by the image sensor 25 and outputs the electric signal to the operational amplifier 26. The analog image signal input from the amplifier 25 is amplified at a predetermined magnification and impedance-converted, and output to the A / D converter 27. The A / D converter 27 quantizes the image signal input from the operational amplifier 26 into a predetermined number of bits, and outputs it as shading correction data to the line buffer 29 and the abnormal pixel detection unit 31 via the shading correction unit 28. Then, the shading correction data (white reference data) is collected (Step S203), and the control unit 2 checks whether the collection of all the shading correction data, that is, the shading correction data for one line is completed (Step S204). .

If the collection of the shading correction data for one line has not been completed, the control unit 2 returns to step S203 to continue the collection of the shading correction data.
Each data value Vp of all the shading correction data is sequentially compared with the output level determination reference value THp to determine whether there is a data value Vp smaller than the output level determination reference value THp (step S205).

In step S205, when there is a data value Vp smaller than the output level determination reference value THp, the control unit 2
Stores the pixel position of the shading correction data having the data value Vp smaller than the output level determination reference value THp in the system memory 3, and there is a data value Vp smaller than the output level determination reference value THp for all the shading correction data. If there is a data value Vp smaller than the output level determination reference value THp,
The lighting condition is changed, and the LED array 22 is turned on by the LED control unit 23 under the LED lighting condition (step S2).
06), the shading correction data is collected (step S203). This change of LED lighting condition
Among the LEDs of the array 22, the LEDs corresponding to the pixel positions of the shading correction data having the data value Vp smaller than the output level determination reference value THp stored in the system memory 3 are individually driven or each predetermined block. This is performed by controlling the current and adjusting the amount of light. For example, the drive current is increased for each LED of the LED array 22 corresponding to the area where the data value Vp of the shading correction data is low, or the drive current is increased for each predetermined number of LEDs to increase the light amount. The drive current is reduced for each LED or a predetermined number of LEDs in the LED array 22 corresponding to the high region, and the light amount is reduced, so that the data value Vp is substantially the same level over one line.

If there is no data value Vp smaller than the output level determination reference value THp in step S205, the control unit 2 checks whether the characteristic value Vu of the shading correction data is smaller than the uniformity determination reference value THu (step S205). S207), the characteristic value Vu is equal to the uniformity determination reference value THu.
If not smaller, change the LED lighting conditions,
The LED array 22 is turned on by the LED control unit 23 under the LED lighting conditions (step S206), and white reference data is collected (step S203). The characteristic value Vu of the shading correction data is a value indicating the non-uniformity of the shading correction data for one line, and is a value indicating a fluctuation range of the output value of the shading correction data. The value obtained by subtracting the minimum output value from the output value and dividing it by the maximum output value (Vu =
(Maximum value−minimum value) / maximum value). Further, the uniformity determination reference value THu indicates an allowable value of the fluctuation range of the output value of the shading correction data.

In step S207, when the characteristic value Vu of the shading correction data becomes smaller than the uniformity determination reference value THu, the control unit 2 reads the original 21 with the shading correction data stored in the line buffer 29. Then, it is checked whether the reading of the document 21 is completed (step S209).
If the reading of the original 21 is not completed in step S209, the control unit 2 continues reading the original 21 (step S208), and completes the reading of all the originals 21 (step S209). I do.

As described above, the facsimile apparatus 1 according to the present embodiment performs shading correction by reading the white reference plate 24 to obtain shading correction data and reading the shading correction of the optical system before reading the original 21. Based on the correction data, the LEDs of the LED array 22
Is adjusted for each LED or a plurality of LEDs.

Therefore, the LED array 2 as a light source
2 can be made more appropriate and uniform, and the image quality of the read image can be further improved.

FIG. 5 is a diagram showing a third embodiment of a light emitting element driving device and an image reading device according to the present invention. In this embodiment, an LED array as a light source is used based on collected shading correction data. In addition to controlling the light emission condition of each LED, a warning is issued when the light emission amount of the LED exceeds a certain amount.

This embodiment is applied to a facsimile machine similar to that of the first embodiment.
In the description of the present embodiment, the description will be made using the reference numerals used in the description of the first embodiment as they are.

In the facsimile apparatus 1 of this embodiment, the LED array 22 which is the light source of the
Although the drive is controlled by the LED lighting control unit 23 as in the embodiment, the facsimile apparatus 1 of the present embodiment particularly turns on / off the plurality of LEDs of the LED array 22 individually or in units of a plurality. In addition to the control, the light emission amount is controlled, and a warning is issued when the light emission amount of the LED array 22 exceeds a certain amount.

That is, in the facsimile apparatus 1, as shown in FIG. 5, when a plurality of documents 21 are placed on a document table (not shown), a start key on the operation panel 11 is turned on, and a reading start instruction is issued. (Step S301) First, the control unit 2 turns on the LED array 22 that is a light source at a preset light amount or under the lighting condition of the light amount set in the previous light amount adjustment processing, and the white reference plate 24 is turned on. Is read to obtain shading correction data. The output level determination reference value THp for evaluating the output level of the shading correction data at this time and the uniformity of the output level of one line of the shading correction data are determined. LED for determining uniformity determination reference value THu for determination
An LED lighting condition determination reference value THLED for determining whether or not the lighting condition has reached an abnormal value is set (step S302).

The control unit 2 determines that the set lighting condition of the LED array 22 is the LED lighting condition determination reference value THLED.
Is checked (step S303). If not, the reflected light of the light emitted from the LED array 22 to the white reference plate 24 is transmitted to the image sensor 2 in the same manner as described above.
5 and converts the signal into an electric signal through the operational amplifier 26 to A / D
The data is output to the converter 27, quantized to a predetermined number of bits by the A / D converter 27, and is used as shading correction data.
Line buffer 29 via shading correction unit 28
Then, the data is output to the abnormal pixel detection unit 31 and the shading correction data (white reference data) is collected (step S30).
4).

The control unit 2 checks whether the collection of all the shading correction data, that is, the shading correction data for one line has been completed (step S30).
5) If the collection of the shading correction data for one line is not completed, the process returns to step S304 to continue the collection of the shading correction data, and when the collection of the shading correction data is completed, the data of all the shading correction data is obtained. The value Vp is sequentially compared with the output level determination reference value THp to determine whether there is a data value Vp smaller than the output level determination reference value THp (step S).
306).

In step S306, when there is a data value Vp smaller than the output level determination reference value THp, the control unit 2
Stores the pixel position of the shading correction data having the data value Vp smaller than the output level determination reference value THp in the system memory 3, and there is a data value Vp smaller than the output level determination reference value THp for all the shading correction data. The output level determination reference value T
If there is a data value Vp smaller than Hp, the LED lighting condition is changed, that is, the light emission amount of the LED array 22 is changed individually or in units of a plurality of LEDs. LED array 2
2 is turned on (step S307), and the LED lighting condition (light emission amount) is set to the LED lighting condition determination reference value THLED.
Is checked (step S303). As described above, the change of the LED lighting condition is performed by changing the data value Vp of each LED of the LED array 22 smaller than the output level determination reference value THp stored in the system memory 3.
Corresponding to the pixel position of the shading correction data of
D is performed individually or for each predetermined block by controlling the drive current to adjust the light amount.

If the changed lighting condition of the ED array 22 does not exceed the LED lighting condition determination reference value THLED in step S303, the control unit 2 performs white reference data collection (steps S304 and S305), and again. It is checked whether there is a data value Vp smaller than the output level judgment reference value THp (step S306). If there is no data value Vp smaller than the output level judgment reference value THp, the characteristic value Vu of the shading correction data is set to the uniformity judgment reference. It is checked whether the value is smaller than the value THu (step S308).

In step S308, if the characteristic value Vu is not smaller than the uniformity determination reference value THu, the control unit 2
ED lighting conditions are changed and L
The LED array 22 is turned on by the ED control unit 23 (step S307), and the changed LED lighting condition
It is checked whether or not the lighting condition determination reference value THLED has been exceeded (step S303). If not, the same processing as described above is performed from the collection of the white reference data (step S30).
4-S308).

In step S308, the characteristic value Vu of the shading correction data is set to the uniformity determination reference value THu.
If it is smaller, the control unit 2 stores the shading correction data in the line buffer 29, and
1 is read (step S309), and it is checked whether the reading of the document 21 is completed (step S31).
0). In step S310, when the reading of the document 21 is not completed, the control unit 2 continues reading the document 21 (step S309). When reading of all the documents 21 is completed (step S310), the process ends. I do.

If the LED lighting condition (light emission amount) exceeds the LED lighting condition determination reference value THLED in step S303, the control unit 2 determines that there is some abnormality in the optical system, and A warning to that effect is displayed and output on the display, and the process ends without reading the document 21 (step S311). The notification of the warning is not limited to displaying the warning on the display, but may be a warning by voice or the like.

As described above, the facsimile apparatus 1 of the present embodiment indicates that there is an abnormality when the light emission amount of the LED of the LED array 22 exceeds the LED lighting condition determination reference value THLED which is a preset reference light emission amount. Is displayed and the warning is output.

Therefore, the abnormality of the image reading apparatus can be promptly recognized, and the maintenance performance can be improved.

FIG. 6 is a diagram showing a fourth embodiment of the light emitting element driving device and the image reading device according to the present invention. In this embodiment, only the LEDs in the area corresponding to the document size are turned on. , To reduce power consumption.

This embodiment is applied to a facsimile apparatus similar to that of the first embodiment.
In the description of the present embodiment, the description will be made using the reference numerals used in the description of the first embodiment as they are.

In the facsimile apparatus 1 of this embodiment, the LED array 22 which is the light source of the
The drive is controlled by the LED lighting control unit 23 in the same manner as in the embodiment described above. In the facsimile apparatus 1 of the present embodiment, in particular, the plurality of LEDs of the LED array 22 are turned on individually or in units of a plurality of LEDs. In addition to controlling the / non-lighting control and the amount of emitted light, the lighting range of the LEDs of the LED array 22 is changed according to the document size.

Although not shown, the facsimile apparatus 1 is provided with a document size detection sensor for detecting the size of the document 24 set on the document table, for example, a reflection type optical sensor in the scanner 5. Is controlled in accordance with the detected document size.

That is, in the facsimile apparatus 1, as shown in FIG. 6, when a plurality of documents 21 are placed on a document table (not shown), a start key on the operation panel 11 is turned on, and a reading start instruction is issued. (Step S401), the control unit 2 detects the document size of the document 24 set by the document size detection sensor (Step S402), and based on the detected document size, the LED of the LED array 22.
Is selectively lit (step S403). That is, the control unit 2 selects an LED in a range that can irradiate an area slightly larger than the original area corresponding to the detected original size from among the plurality of LEDs arranged in the array of the LED array 22, and turns on the LED. The controller 23 is driven to light up.

When the control section 2 selectively turns on the LED array 22, the control section 2 causes the white reference plate 24 to be read, obtains shading correction data, and obtains the light emission amount of the LED by any of the methods described in the above embodiments. Is determined, the light emission amount of the LED array 22 is changed as necessary, and the shading correction data is stored in the line buffer 29 (step S405).

Thereafter, the control unit 2 sends the original 2 to the scanner 5.
1 (step S406), and the original 21 is read.
It is checked whether or not reading has been completed (step S40).
7). If the reading of the document 21 is not completed in step S407, the control unit 2 continues reading the document 21 (step S406), and completes the reading of all the documents 21 (step S407). I do.

As described above, according to the facsimile apparatus 1 of the present embodiment, a plurality of LEs arranged in a row of the LED array 22 according to the document width detected by the document size detection sensor.
Among D, the range of the LED to emit light is changed.

Therefore, the LED for irradiating an unnecessary area outside the document area can be turned off, and unnecessary power consumption can be reduced.

Further, of the light emitting elements of the LED array 22, LEDs in a range that irradiates a range wider than the detected document width by a predetermined width are emitted.

Therefore, even when the document 21 is skewed, light necessary for reading the document 21 can be emitted from the LED array 22, and the document 21 can be read stably.

Although the invention made by the inventor has been specifically described based on the preferred embodiments, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the invention. It goes without saying that it is possible.

For example, in each of the above-described embodiments, the case where the present invention is applied to a facsimile apparatus has been described. However, the present invention is not limited to the facsimile apparatus, and may be applied to, for example, a copying apparatus.

[0121]

According to the light emitting element driving device of the first aspect of the present invention, a light emitting element array in which a plurality of light emitting elements are arranged in a row is turned on and off for each light emitting element and / or each light emitting element. Since non-lighting control is performed, precise lighting control can be performed according to the application, and the usability of the light emitting element driving device can be improved.

According to the image reading apparatus of the second aspect, light from a light emitting element array in which a plurality of light emitting elements are arranged in a row is applied to a document located on the document reading surface, and reflected light of the document is reflected. When reading the image of the original by the control unit, the control unit sets the lighting / non-lighting and / or the light emission amount as the lighting condition of the light emitting element array via the drive control means for each light emitting element and / or for each of a plurality of light emitting elements. Since the control is performed, the light emitting element array as the light source can be precisely turned on / off and the amount of emitted light can be controlled in accordance with the reading state of the document, and the image quality of the read image can be improved.

According to the image reading apparatus of the present invention, before reading the original, the white reference member is read to obtain the white reference data, and when the shading correction of the optical system is performed, the white reference data is obtained. When the dirt on the document reading surface is detected based on the dimming, the light emitting element or the plurality of light emitting elements at the position corresponding to the dirt is turned on to notify the dirt. It can be recognized, and work efficiency can be improved.

According to the image reading apparatus of the present invention, when the dirt on the original reading surface is detected based on the white reference data, the light emitting element or the plurality of light emitting elements at the position corresponding to the dirt is periodically emitted. Since the dirt is blinked to notify the dirt, the operator and the like can more appropriately recognize the dirt position on the document reading surface, and the working efficiency can be further improved.

According to the image reading apparatus of the present invention, before reading the original, the white reference member is read and the white reference data is obtained to perform the shading correction of the optical system. , The amount of light emitted from the light emitting elements of the light emitting element array is adjusted for each light emitting element or for each of the plurality of light emitting elements, so that the amount of light emitted from the light emitting element array as the light source can be made more appropriate and uniform. In addition, the image quality of the read image can be further improved.

According to the image reading apparatus of the present invention, when the amount of emitted light exceeds a preset reference amount of emitted light, a predetermined warning is output to notify the abnormality of the image reading apparatus. And maintenance performance can be improved.

According to the image reading apparatus of the present invention, the range of the light emitting elements to emit light in the light emitting elements of the light emitting element array is changed according to the document width detected by the document size detecting means. The light emitting element that irradiates an unnecessary area outside the document range can be turned off, so that unnecessary power consumption can be reduced.

According to the image reading apparatus of the present invention, among the light emitting elements of the light emitting element array, the light emitting elements in a range that irradiates a range wider than the detected document width by a predetermined width are made to emit light. Is skewed, the necessary light can be emitted from the light emitting element array to the document, and the document can be read stably.

[Brief description of the drawings]

FIG. 1 is a block diagram of a facsimile apparatus to which a first embodiment of a light emitting element driving device and an image reading device according to the present invention is applied.

FIG. 2 is a block diagram of a main part of the scanner of FIG. 1;

FIG. 3 is a flowchart showing abnormal pixel detection processing and LED array drive control processing by the facsimile apparatus of FIG. 1;

FIG. 4 is a flowchart showing shading management processing and LED array drive control processing by a facsimile apparatus to which the second embodiment of the light emitting element driving device and the image reading device according to the present invention is applied.

FIG. 5 is a flowchart illustrating shading management processing and LED array drive control processing by a facsimile apparatus to which the third embodiment of the light emitting element driving device and the image reading device according to the present invention is applied.

FIG. 6 is a flowchart illustrating an LED array drive control process according to a document size by a facsimile apparatus to which a fourth embodiment of the light emitting element driving device and the image reading device according to the present invention is applied.

FIG. 7 is a schematic front view of the configuration of a conventional image reading apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Facsimile apparatus 2 Control part 3 System memory 4 Parameter memory 5 Scanner 6 Plotter 7 Network control unit 8 Modem 9 Image storage part 10 Encoding / decoding part 11 Operation panel 12 System bus 21 Document 22 LED array 23 LED lighting control part 24 White reference plate 25 Image sensor 26 Operational amplifier 27 A / D converter 28 Shading correction unit 29 Line buffer 30 Digital image processing unit 31 Abnormal pixel detection unit

Claims (8)

[Claims] 1. A light emitting element driving device comprising: a light emitting element array in which a plurality of light emitting elements are arranged in a row; and drive control means for driving and controlling the light emitting element array. A light-emitting element driving device that controls lighting and non-lighting of a light-emitting element array for each of the light-emitting elements and / or for each of a plurality of light-emitting elements. 2. A document positioned on a document reading surface is irradiated with light from a light emitting element array in which a plurality of light emitting elements driven by a drive control means are arranged in a row, and the reflected light is used to reflect an image on the document. In the image reading apparatus for reading light, the drive control means controls lighting / non-lighting and / or light emission amount as lighting conditions of the light emitting element array for each of the light emitting elements and / or for each of the plurality of light emitting elements. An image reading apparatus comprising a control unit. 3. The image reading apparatus further includes a predetermined white reference member for providing white reference data, and reads the white reference member to obtain the white reference data before reading the document. An image reading apparatus for performing shading correction of an optical system, wherein the control unit detects a stain on the document reading surface based on the white reference data, and detects a position corresponding to the stain via the drive control unit. 3. The image reading apparatus according to claim 2, wherein the light emitting element or the plurality of light emitting elements is turned on to notify the stain. 4. When the control means detects a stain on the document reading surface based on the white reference data, the control means controls the drive control means to detect the light emitting element or the plurality of light emitting elements at a position corresponding to the stain. 4. The image reading apparatus according to claim 3, wherein the element is blinked at a predetermined cycle to notify the stain. 5. The image reading apparatus according to claim 1, further comprising a predetermined white reference member for providing white reference data, reading the white reference member to obtain the white reference data before reading the document. An image reading apparatus that performs shading correction of an optical system, wherein the control unit is configured to, based on the white reference data, determine a light emission amount of the light emitting element of the light emitting element array through the drive control unit. The image reading apparatus according to claim 2, wherein the adjustment is performed for each of the plurality of light emitting elements. 6. The image reading apparatus according to claim 5, wherein said control means outputs a predetermined warning when said light emission amount exceeds a preset reference light emission amount. 7. The image reading apparatus further comprises a document size detecting means for detecting at least a width of the document on the document reading surface, and the control means responds to a document width detected by the document size detecting means. The image according to any one of claims 2 to 6, wherein a range of the light emitting element to emit light among the light emitting elements of the light emitting element array is changed via the drive control means. Reader. 8. The light-emitting element of the light-emitting element array in the light-emitting element of the light-emitting element array in a range that is wider than the detected document width by a predetermined width through the drive control means. The light is emitted.
The image reading device according to claim 1.