JPH09258531A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To keep an image density constant by preventing the fluctuation of the image density corresponding to the increase of the cumulative total of the number of copies. SOLUTION: This device is provided with an original indicator 24 including a pointer 24a integrally formed with a leg part 44e formed at a fixed interval from a black and white reference plate 26a-26b located at the back of an indicator base 24b. The leg part 24e is moved in the longitudinal direction of the black and white reference plate 26a-26b, along therewith, in such a manner that the pointer 24a is moved. A cleaner 24f for removing dirt, dust, toner scattered from a developing device and a photoreceptor drum, etc., in fear of sticking to the black and white reference plate 26a-26b is arranged between the leg part, 24e of the pointer 24a and the black and white reference plate 26. As the cleaner, a molt plane, a felt, etc., being a little thicker than the gap between the leg part 24e and the black and white reference plate 26 are used.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus for forming an image on a photosensitive member by an electrostatic photography process, developing the image using toner, and then outputting the image on a sheet, and an image reading apparatus for reading an image on an original. Regarding

[0002]

2. Description of the Related Art In an image forming apparatus or an image reading apparatus using an electrostatic photography process, the reflected light from an original obtained by irradiating the original with light is photoelectrically converted by using a CCD sensor. The image data corresponding to the image is obtained.

By the way, when an image of an original is read using a CCD sensor, reflected light of a white image and a black image from a black and white reference plate on which a white image and a black image, which are brightness references, are integrally arranged. CC based on the output obtained by reading
The variation (deviation) of photoelectric conversion characteristics between pixels of the D sensor is corrected.

The white image and the black image on the black-and-white reference plate are located at the position where the document surface is located when the document is set on the document table, that is, the distance between the document-side surface of the document table and the light-receiving surface of the CCD sensor. Are preferably arranged at the same position, and in many cases, they are arranged integrally with the document indicating plate on the back surface of the document indicating plate that indicates the position of the leading edge of the document when setting the document on the document table.

[0005]

As described above, when the black-and-white reference plate is located on the back side of the document indicating plate, the front end of the document abuts against the document indicating plate when setting the document on the document table. The fine powder of the original material, that is, paper dust, generated when the original is written with a pencil, and the original table due to frictional charging that adheres to the original or is generated by rubbing the original table with the original. There is a problem that the brightness of the reference white image changes due to dust and dirt attracted to the. Therefore, the black and white reference plate is cleaned every predetermined time.

However, since the black-and-white reference plate is provided at a position where it cannot be cleaned without removing any of the parts fixed to the apparatus body such as the document table or the document pointing plate, the cleaning time is only increased. There is a problem that the cleaning procedure is complicated. In the image forming apparatus, the toner scattered from the developing device, the photoconductor, the cleaning device, or the like is relatively easily adhered by being convected by the convection inside the device generated by the heat from the illumination lamp. Cleaning is required.

Further, when the part to be removed for cleaning is an original pointing plate, if the original pointing plate is not correctly attached after the cleaning is completed, a non-right angle component, that is, a rectangular image is added to the read image (copy image). Is distorted into a parallelogram, and the absolute position of the image with respect to the leading edge of the document varies.

In this case, the position confirmation work and the work for adjusting the position of the original pointing plate, which are required after cleaning, become complicated, and the time during which the device cannot be used for the work is increased, resulting in a running cost (maintenance cost). ) Is required undesirably. An object of the present invention is to provide an image reading apparatus and an image forming apparatus capable of maintaining a constant image density.

[0009]

SUMMARY OF THE INVENTION The present invention has been made based on the above-mentioned problems. The reading means for optically reading an image of a document and outputting image information, and the optical reading accuracy of the reading means are provided. An image reading apparatus comprising: a correction unit that corrects the reading member by reading a reference member having a reference density; and a cleaning unit that cleans the reference member at a predetermined timing. It is a thing.

Further, according to the present invention, the reading means for optically reading the image of the original and outputting the image information, and the optical reading accuracy of the reading means is such that the reading means reads the reference member having the reference density. Correction means to correct by
An instructing means for instructing the size of a document area that can be read by the reading means;
An image reading apparatus comprising: a cleaning unit that cleans the reference member at a predetermined timing.

Further, according to the present invention, the reading means for optically reading the image of the original and outputting the image information, and the optical reading accuracy of the reading means are such that the reading means reads the reference member having the reference density. And a cleaning unit that is integrally formed with the instructing unit and that cleans the reference member, and a cleaning unit that corrects the document area that can be read by the reading unit. The present invention provides an image reading apparatus, characterized in that the image reading apparatus is provided with:

Still further, according to the present invention, a reading means for optically reading an image of a document and outputting image information, and an optical reading accuracy of the reading means, the reading means reads a reference member having a reference density. Correcting means for correcting the size of the original area readable by the reading means, driving means for moving the indicating means along the longitudinal direction of the indicating means, and the indicating means. Cleaning means for integrally cleaning the reference member and the driving means when the power of the apparatus is turned on,
The present invention provides an image reading apparatus comprising: drive means control means for moving the instruction means over the entire area in the longitudinal direction. Still further, according to the present invention, a reading unit that optically reads an image of a document and outputs image information, and an optical reading accuracy of the reading unit are obtained by causing the reading unit to read a reference member having a reference density. An image forming apparatus comprising: a correction unit that corrects the image, a cleaning unit that cleans the reference member at a predetermined timing, and an image forming unit that forms an image corresponding to the image data read by the reading unit. A device is provided.

Still further, according to the present invention, a reading means for optically reading an image of a document and outputting image information, and an optical reading accuracy of the reading means, the reading means reads a reference member having a reference density. Correction means for correcting the size of the original area that can be read by the reading means, and cleaning means that is integrally formed with the instruction means and cleans the reference member at a predetermined timing. And an image forming unit that forms an image corresponding to the image data read by the reading unit.

Still further, according to the present invention, the reading means for optically reading the image of the original and outputting the image information, and the optical reading accuracy of the reading means, the reading means reads the reference member having the reference density. Correction means for correcting the size of the original area that can be read by the reading means, cleaning means for integrally cleaning the reference member, and cleaning means for cleaning the reference member. Control means for moving the means over the entire area in the longitudinal direction of the indicating means each time it is energized, and latent image forming means for forming a latent image on the photoconductor corresponding to the image data read by the reading means. And a developing unit for developing the latent image formed on the photoconductor by the latent image forming unit. Still further, according to the present invention, a reading unit that optically reads an image of a document and outputs image information, and an optical reading accuracy of the reading unit is such that the reading unit reads a reference member having a reference density. Correction means, correction means for correcting the size of the original area that can be read by the reading means, driving means for moving the indicating means along the longitudinal direction of the indicating means, and the instructing means. Cleaning means for cleaning the reference member, and drive means control means for moving the drive means over the entire area in the longitudinal direction of the indicating means when the power of the apparatus is turned on.
The latent image forming means forms a latent image on the photoconductor corresponding to the image data read by the reading means, and the developing means develops the latent image formed on the photoconductor by the latent image forming means. The present invention provides an image forming apparatus characterized by the following.

[0015]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the image forming apparatus, that is, the laser beam type digital copying apparatus 2
An image forming unit for copying information corresponding to an image of an original on a recording sheet, that is, a copying apparatus main body 10 and a copying apparatus main body 1
An automatic feeding device (hereinafter referred to as A
DF) 100.

The copying apparatus main body 10 includes a document reading unit 12 that reads image information of a document D, and an image forming unit 14 that forms an image based on image data read by the document reading unit 12 or image data supplied from the outside. A sheet feeding section 16 for feeding the recording sheet holding the image formed by the image forming section 14, a sheet conveying section 18 for conveying the sheet on which the image formed by the image forming section 14 is transferred in a predetermined direction, etc. Is included.

The upper part of the copying apparatus main body 10 includes an ADF
A document table (document table) 20 on which a document D to be copied is placed, that is, a document table 20 for holding the document D is disposed at a position of 100, which is opposed to a conveyance belt described later.

At the one end of the document table 20, a document indicating plate for instructing the position of the leading edge to be set when the document D is set (for the purpose of stopping the leading edge of the document conveyed by the ADF 100 when using the ADF 100). , Which is called a document stopper).

The document stopper 22 is shown in FIGS.
A document indicator, which will be described later with reference to FIGS. 3A and 3B, is integrally formed. Below the document table 20, the document table 2 is substantially parallel to the document table 20.
The first carriage 30, which is arranged so as to be movable along 0, takes out the information written on the document as light and darkness of the light, and is driven by the first carriage 30, and the information taken out by the carriage 30 is recorded on the information recording medium described later. The second carriage 40 is included in the second carriage 40.

The first carriage 30 has an illumination lamp 32 for illuminating the original document D, a reflector 34 for converging light from the illumination lamp 32 on the original document D and increasing illumination efficiency, and second reflection light from the original document D. A first mirror 36 that reflects the light toward the carriage 40 is arranged.

The first carriage 36 is attached to the second carriage 40.
A second mirror 42 that turns back the reflected light reflected from the original 90 ° and a third mirror 44 that turns back the reflected light from the document D that has been turned back through the second mirror 42 further 90 ° are arranged.

Below the first carriage 30 and in a plane including the optical axis of the third mirror 44 of the second carriage 40, an image forming lens 46 for converging the reflected light from the document D is provided. , And a CCD sensor 48 that thresholds the reflected light from the document D at a predetermined threshold level to perform photoelectric conversion, that is, binarizes it at a predetermined threshold value.

The image forming section 14 includes a drum-shaped photosensitive member, that is, a photosensitive drum 50, which is an image bearing member and is disposed substantially in the center of the main body 10. Around the photoreceptor drum 50, a charging device 52 as a charging unit for charging the photoreceptor drum 50 to a predetermined surface potential, and an electrostatic latent image formed on the photoreceptor drum 50 via a laser exposure device described later. A developing device 54 as a developing unit that develops a latent image by supplying toner (not shown) and a cleaning device 56 that removes the toner remaining on the photosensitive drum 50 and removes the charge remaining on the photosensitive drum 50 are provided. Are arranged in order along the direction in which the photosensitive drum 50 is rotated.

In the vicinity of the photoconductor drum 50 and upstream of the developing device 54 in the direction in which the photoconductor drum 50 is rotated, the photoconductor drum 50 charged to a predetermined potential by the charging device 52 is provided. On the other hand, an exposure position 58a to which a laser beam from a laser exposure device 58 which exposes a latent image corresponding to image data is irradiated is defined.

Further, the developing device 54 and the cleaning device 5
A transfer device 60 for transferring a latent image, that is, a toner image, developed on the photosensitive drum 50 by the developing device 54 to a transfer material supplied from a cassette described later, for example, a copy sheet P, is disposed between the transfer device 60 and the transfer device 6. I have.

On the right side of the image forming unit 14, the image forming unit 1
The paper cassette 62a for storing the paper P for holding the image formed by the paper cassette 4 and a bypass tray 62b formed integrally with the cassette 62a are arranged above the paper cassette 62a. Below the cassette 62a, for example, a large-capacity cassette (hereinafter, a large capacity cassette, L
62c).

Between the paper cassette 62a and the large-capacity cassette 62c and the photosensitive drum 50, the cassette 62 is provided.
a paper feed roller 64a and an upper paper feed guide 66 that guide the paper P supplied from
a, and a lower paper feed roller 64b and a lower paper feed guide 66b that guide the paper P supplied from the LCC 62c toward the photosensitive drum 50 are arranged, respectively.
The bypass tray 62b is provided with a bypass feed roller 68 for guiding the paper P placed on the tray 62b to the upper paper feed roller 64a.

Between the paper feed guides 66a and 66b and the photoconductor drum 50, the paper P fed from the cassette 62a or the bypass tray 62b and the LCC 62c is temporarily stopped to correct the inclination of the paper P, and A registration roller 70 that is formed on the surface of the photosensitive drum 50 and that aligns the leading end positions of the image, that is, the toner image and the toner image that is conveyed toward the transfer roller 60 with the rotation of the photosensitive drum 50, is arranged.

A transfer device 60 is provided on the left side of the image forming section 14.
Fixing device 72 and fixing device 7 for fixing the toner image on paper P on which the toner image has been transferred from photoreceptor drum 50
A transfer device 74 that is disposed between the transfer device 60 and the transfer device 60 and sends out the sheet P on which the toner image has been transferred to the fixing device 72, and the sheet P on which the image is fixed via the fixing device 72.
Gate 76 and branch gate 7 for guiding the sheet to the outside of the copying apparatus main body 10 or to a sheet reversing section to be described later.
A discharge roller 78 for sending out the paper P guided to the outside of the copying apparatus main body 6 by the reference numeral 6 to the outside of the copying apparatus main body 10 and a tray 80 for holding the discharged paper P are arranged.

Below the image forming section 14, a branch gate 7 is provided.
6, the sheet reversing section 9 for guiding the sheet P, which has been branched by the sheet P, to the registration rollers 70 again.
0 is arranged.

The sheet reversing unit 90 guides the sheet P having an image already copied on one side thereof, and a reversing guide 91 and a reversing guide 9.
1 is stored at a predetermined interval, that is, a transport roller 92, a reversing guide 91, and a storage for temporarily storing the paper P guided by the transport roller 92, which are arranged at intervals defined depending on the size of the reversible paper P. A reverse paper feed roller 94 for transporting the paper P stored in the area 93 and the storage area 93 toward the registration roller 70, and guides the paper P pulled out from the rear end side by the reverse paper feed roller 94. The reversing paper feed guide 95 includes an intermediate conveyance roller 96 that propels the paper P passing through the reversing paper supply guide 95 toward the registration roller 70.

As shown in FIG. 2, the document stopper 22
A slit-shaped opening 22a extending in the longitudinal direction of the document stopper 22 is formed in the. Document stopper 22
A document indicator 24 indicating the position where the document should be set on the document table 20 is disposed below the.

As will be described later with reference to FIG. 3B, the manuscript indicator 24 is a pointer 24a formed so as to be visible through the opening 22a when the opening 22a is viewed from a direction orthogonal to the surface of the manuscript table 20, and the pointer 24a. The opening 22
It has an indicator base 24b which provides a background of the pointer 24a for easy visual recognition from a, and a pointer driving mechanism described later in FIG.

On the back surface of the base 24b of the original indicator 24, there are provided a reference white image 26a and a reference black image 26b for providing reference white light and reference black image light for correcting variations in sensitivity between pixels of the CCD sensor 48. The black and white reference plate 26 is integrally formed with the base 24b.

FIGS. 3A and 3B are a schematic plan view and a partial sectional view showing the structure of the original indicator, respectively. As shown in FIG. 3 (a), the pointer 24a of the document indicator 24 is fixed at a predetermined position of an endless carrier 24c such as a toothed belt or a wire. One end of the endless carrier 24c has a stepping motor.
(Indicator motor) It is rotatably supported by a pulley connected to the rotating shaft of 24d. As a result, the stepping motor 24d is rotated and the endless carrier 24c is rotated.
Is moved, the pointer 24a is reciprocated along the longitudinal direction of the document stopper 22.

As shown in FIG. 3B, the pointer 24a of the document indicator 24 has a leg portion 24e formed at a predetermined interval with respect to the black and white reference plate 26 located on the back surface of the base 24b. ing. The leg 24e is formed substantially integrally with the pointer 24a, and is moved along the black-and-white reference plate 26 in the longitudinal direction of the black-and-white reference plate 26 by moving the pointer 24a.

The leg 24e of the pointer 24a and the black and white reference plate 26
In between, dust that may be attached to the black and white reference plate 26,
A cleaner 24f for removing dust, scattered toner and the like generated from the developing device and the photosensitive drum is arranged. The cleaner 24f is an elastic member having a thickness slightly larger than the distance between the leg portion 24e and the black-and-white reference plate 26, and is preferably made of maltoprene or felt.

FIG. 4 schematically shows a control section for controlling each section of the copying machine shown in FIGS. As shown in FIG. 4, the control unit 100 includes a CPU (Central Processing Unit) 110 as a main control unit.

The CPU 110 includes a control panel (not shown) and many mechanisms or circuits constituting the copying apparatus main body 2, for example, a main motor (not shown) for rotating the photosensitive drum 50 and the first and second carriages 30.
And 40 not shown scanning motor for moving
When the (stepping motor) and the developing motor for rotating the developing roller of the developing device are arranged independently of the main motor, the charging voltage is applied to the motor drive circuit 112 for rotating various motors including the developing motor and the charging device 52. The high voltage generating circuit 114 to be supplied, the transfer voltage generating circuit 116 for supplying the transfer voltage to the transfer device 60, and the output signals output from many sensors (not shown) are taken in to obtain C.
The input circuit 118 or the like for notifying the PU 110 is connected.

The CPU 110 also has a stepping motor (indicator motor) 28 for driving the endless transport body 26 to move the document indicator 24 to a predetermined position.
Indicator control circuit 12 for rotating the
0, and a lens motor control circuit 122 for controlling a lens motor (not shown) that moves the imaging lens 46 to a position corresponding to the input copy magnification.

The CPU 110 further has a memory unit 130 in which predetermined initial data, adjustment data set when the apparatus body 2 is assembled, variable data input by an operation panel (not shown), and the like are stored. Are connected.

The memory unit 130 is a read-only memory (RO) in which predetermined numerical data or control data for operating the device 2 are stored.
M) 132, a random access memory (RAM) 134 for storing copy condition data input by an operation panel (not shown) and an image of an original, that is, image data photoelectrically converted by the CCD sensor 48, and the device 2. It includes a non-volatile memory (NVM) 136 in which adjustment data input when assembled, such as a reference voltage for lighting the illumination lamp 32, is stored.

Next, the characteristics of the operation of the digital copying apparatus 2 of the present invention will be described. Referring to FIG. 1, an object to be copied, that is, a document D set at a predetermined position on the document table 20 is brought into close contact with the document table 20 by an ADF (automatic document feeder) 100.

The image of the original that is brought into close contact with the original table 20 is reflected by the illumination lamp 32 and the reflector 34 and is reflected by the first carriage 30.
Of the first mirror 36, the second mirror 4 of the second carriage 40
It is guided to the CCD sensor 48 by the second and third mirrors 44 and the imaging lens 46. Prior to instructing the start of copying or reading by an operation panel (not shown), the imaging lens 46 is moved to a predetermined position corresponding to the input copying magnification. In addition, the pointer 24a of the document indicator 24 is also moved to a position indicating an area where the image of the document can be copied.

The reflected light from the document D, that is, the image information guided by the CCD sensor 48 is photoelectrically converted at a predetermined timing and temporarily stored in the RAM 134 of the memory unit 130.

Next, the photosensitive drum 50 charged to a predetermined potential by the charging device 52 urged by the high voltage generating circuit 114 is intensity-modulated in accordance with the image data stored in the RAM 134. An electrostatic latent image is formed by the laser beam from the laser exposure device 58.

The electrostatic latent image formed on the photosensitive drum 50 is developed as a toner image by the toner supplied through the developing device 54, and then transferred to the paper P by the transfer device 60.

The sheet on which the toner image is transferred is conveyed by the conveying device 7.
4, the toner image, that is, the toner is fixed by the heat provided from the fixing device 72, and then guided to the sheet reversing unit or the outside of the device 2.

The cleaning device 56 removes charges and toner remaining on the surface of the photoconductor drum 50 having the toner image transferred onto the sheet, and is subsequently used for the next image formation.

When the number of copies is two or more, or when the next original is supplied, the above series of copying operations are repeated. On the other hand, when the power of the device 2 is turned on, the RO
As an initial operation stored in M132, the pointer 24a of the document indicator 24 indicates at least the retracted position along the longitudinal direction of the document stopper 22 and the maximum length of the region capable of displaying the range of the document that can be copied (read). Is reciprocated between.

As a result, when the document D is set on the document table 20, a fine powder of the document material, that is, paper dust, which is produced by being abutted against the document stopper 22, graphite powder produced when the document is a pencil writing, the document The document table 2 is attached to the document table 2 or the document table 2 and the document D are rubbed against each other to generate frictional charging.
The reference white light and the reference provided to the CCD sensor 48 from the reference white image 26a and the reference black image 26b of the black-and-white reference plate 26 which may be contaminated by dust and dust attracted to 0 or toner scattered inside the apparatus. The black density is accurately transmitted to the CCD sensor 48.

Therefore, the variation in the sensitivity between the pixels of the CCD sensor 48 does not change as the total number of copying (reading) increases due to the undesired stain of the black-and-white reference plate 26, and is within a certain range. Can be kept within.

When the copying capacity of the copying apparatus 2 is 40 sheets per minute, a maximum of 2400 sheets can be copied per hour, but one day from the monthly average number of sheets announced in the market. When calculating the number of copies per
The maximum number of copies per day can be regarded as about 1000. In an apparatus having a copying capacity of 40 sheets per minute, the frequency of cleaning the black-and-white reference plate 26 is statistically sufficient for every maintenance cycle, that is, every ΔΔ000 sheets. Board 2
The cleaning of 6 prevents the variation in sensitivity between pixels of the CCD sensor 48 from being changed undesirably depending on the contamination of the black and white reference plate 26.

[0054]

As described above, according to the present invention, a black-and-white reference in which a white image and a black image, which serve as a reference for brightness when an image of an original is read using a CCD sensor, is integrally arranged. The plate is cleaned every time the device is powered on.

Therefore, based on the white and black images of the black-and-white reference plate which may be contaminated by paper dust, graphite powder from a pencil, dust attracted to the original table, or toner scattered inside the apparatus. White light and black density input to the CCD sensor are accurately and accurately transmitted to the CCD sensor without changing as the total number of copying (reading) increases.

As a result, the image reading apparatus and the image forming apparatus capable of maintaining the image density constant are provided. Also,
The work cost required for cleaning the black-and-white reference plate and the cost required for checking and adjusting the displacement of the image leading edge position that may occur due to cleaning become unnecessary, and the running cost (maintenance cost) is reduced.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing an image forming apparatus in which a document indicator according to an embodiment of the present invention is incorporated.

FIG. 2 is a schematic diagram illustrating a black-and-white reference plate incorporated in the image forming apparatus shown in FIG.

FIG. 3 is a schematic diagram showing a document indicator of the image forming apparatus shown in FIGS. 1 and 2.

FIG. 4 is a block diagram showing a control block of a main part of the image forming apparatus shown in FIG.

[Explanation of symbols]

 2 ... Copying device (image forming device), 20 ... Document table, 22 ... Document stopper (document pointing plate), 24 ... Document indicator, 24a ... Pointer, 24b ... Indicator base, 24c ... Toothed belt, 24d ... Stepping motor, 24e ... Legs, 26 ... Monochrome reference plate, 30 ... First carriage, 40 ... Second carriage, 46 ... Imaging lens, 48 ... CCD sensor, 50 ... Photosensitive drum, 62a ... Cassette, 62b ... Cassette, 70 ... Registration roller, 100 ... Control part, 110 ... CPU, 112 ... Motor drive circuit, 114 ... High voltage generation circuit, 116 ... Transfer voltage generation circuit, 118 ... Input circuit, 120 ... Indicator control circuit, 132 ... ROM, 134 ... RAM , D ... manuscript.

Claims (8)

[Claims] 1. A reading means for optically reading an image of a document and outputting image information, and an optical reading accuracy of the reading means is corrected by causing the reading means to read a reference member having a reference density. And a cleaning unit that cleans the reference member at a predetermined timing. 2. A reading means for optically reading an image of a document and outputting image information, and an optical reading accuracy of the reading means is corrected by causing the reading means to read a reference member having a reference density. Correction means, instruction means for instructing the size of the original area that can be read by the reading means, and cleaning means integrally formed with the instruction means for cleaning the reference member at a predetermined timing. An image reading apparatus characterized by: 3. A reading means for optically reading an image of an original and outputting image information, and an optical reading accuracy of the reading means is corrected by causing the reading means to read a reference member having a reference density. Correction means, an instruction means for instructing the size of a document area that can be read by the reading means, a cleaning means integrally formed with the instruction means for cleaning the reference member, and the cleaning means An image reading apparatus comprising: a control unit that moves the display unit over the entire region in the longitudinal direction each time the display unit is moved. 4. A reading means for optically reading an image of a document and outputting image information, and an optical reading accuracy of the reading means is corrected by causing the reading means to read a reference member having a reference density. Correction means, an instructing means for instructing the size of a document area that can be read by the reading means, a driving means for moving the instructing means along the longitudinal direction of the instructing means, and the instructing means integrally. Cleaning means for cleaning the reference member, and drive means control means for moving the drive means over the entire region in the longitudinal direction of the indicating means when the power of the apparatus is turned on. An image reading device characterized by. 5. A reading means for optically reading an image of an original and outputting image information, and an optical reading accuracy of the reading means is corrected by causing the reading means to read a reference member having a reference density. Image forming means comprising: a correcting means for cleaning the reference member, a cleaning means for cleaning the reference member at a predetermined timing, and an image forming means for forming an image corresponding to the image data read by the reading means. apparatus. 6. A reading means for optically reading an image of a document and outputting image information, and an optical reading accuracy of the reading means is corrected by causing the reading means to read a reference member having a reference density. Correction means, an instructing means for instructing the size of a document area that can be read by the reading means, a cleaning means formed integrally with the instructing means and cleaning the reference member at a predetermined timing, and the reading means. And an image forming unit that forms an image corresponding to the image data read by the unit. 7. A reading means for optically reading an image of an original and outputting image information, and an optical reading accuracy of the reading means is corrected by causing the reading means to read a reference member having a reference density. Correction means, an instruction means for instructing the size of a document area that can be read by the reading means, a cleaning means integrally formed with the instruction means for cleaning the reference member, and the cleaning means Each time the control means is moved over the entire area in the longitudinal direction of the indicating means, a latent image forming means for forming a latent image on the photoconductor corresponding to the image data read by the reading means, An image forming apparatus comprising: a developing unit that develops the latent image formed on the photoconductor by the image forming unit. 8. A reading means for optically reading an image of an original and outputting image information, and an optical reading accuracy of the reading means is corrected by causing the reading means to read a reference member having a reference density. Correction means, an instructing means for instructing the size of a document area that can be read by the reading means, a driving means for moving the instructing means along the longitudinal direction of the instructing means, and the instructing means integrally. Cleaning means for cleaning the reference member, driving means control means for moving the driving means over the entire longitudinal direction of the indicating means when the power of the apparatus is turned on, and the reading means. A latent image forming means for forming a latent image on the photoconductor corresponding to the read image data, and a developing means for developing the latent image formed on the photoconductor by the latent image forming means are provided. An image forming apparatus comprising: