JPH10190967A - Image reader and facsimile equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image reader and facsimile equipment with high quality by which an image is read at a proper density. SOLUTION: An original sensor provided to an original carrier section is used to discriminate whether or not an original is set on an original platen (F40). When it is discriminated that the original is set, the scanning by the read object movement scanning system is adopted (F20). When it is discriminated that the original is not set, the scanning by the image read unit moving system is adopted (F10). When it is discriminated that the original S is set, an LED built in a close contact image sensor (CS) is lit by a Vs (F22). Furthermore, when it is discriminated that no original is set, the LED built in the close contact image sensor (CS) is lit by a Vb.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image reading apparatus for reading image information of an object to be read while scanning the same.
There are different methods such as a method of scanning while moving the image reading unit when the object to be read is a thick book or a method of scanning while moving the object to be read when the object to be read is a thin sheet. The present invention relates to an image reading apparatus having a scanning method, and is applied to, for example, a facsimile apparatus.

[0002]

2. Description of the Related Art Conventionally, in a reading apparatus using a contact type image sensor in which a light emitting element array and a light receiving element array are integrally combined as an image reading device, a two-dimensional image is obtained from a thick object such as a book. In order to have a function of reading information and a function of continuously reading a plurality of two-dimensional image information of a fixed sheet-shaped object to be read, the object to be read placed on the glass plate is A contact image sensor is arranged so as to face a reading surface of an object to be read through the main scanning unit, and a main scan is performed in a direction in which a light emitting element array and a light receiving element array of the contact image sensor are arranged. The sensor is placed on a carriage parallel to the glass plate and movable in the direction perpendicular to the main scanning direction, and the carriage is moved in synchronization with the reading timing and speed. By performing sub-scanning, a flat-bed book scanner unit that reads the reading surface of the object to be read as two-dimensional image information is brought into close contact with the thick object to be read placed on the glass plate. For this purpose, a plurality of sheet-like objects to be read are sequentially separated and transported one by one from a plurality of sheet-like objects to be read on a pressure plate for applying a pressure contact force from above, so that the predetermined The sheet-shaped object to be read is supplied from the sub-scanning direction to the reading position of the contact type image sensor waiting at the position at a timing and speed synchronized with the timing and speed of reading, and the sheet-shaped object is read at the reading position. The reading surface of the sheet-like object to be read is read as two-dimensional image information by performing main scanning and sub-scanning on the reading surface of the object to be read. And a feeder-type sheet scanner unit for illuminating an object to be read with a light-emitting element incorporated in the contact type image sensor during reading, and photoelectrically converting reflected light from the object to be read by a light-receiving element. , The brightness of the reflected light is converted into a high or low voltage, and the voltage is quantized by an A / D converter to digitize the image information.

[0003]

However, in the above-mentioned prior art, the light quantity of the light emitting element built in the contact type image sensor depends on the contact type image fixed on the reading object and mounted on the carriage. When using a flatbed scanner that scans while moving the sensor in the sub-scanning direction, or when using a feeder type that fixes the contact-type image sensor to the device and performs reading while transporting the object to be scanned in the sub-scanning direction This was the same as when using the sheet scanner unit. Therefore, by using a pressure plate, the image read using a flatbed scanner unit that reads in a state in which the object to be read is brought into close contact with the glass plate, and the sheet-like object to be read is not loosened at the reading position. A feeder-type sheet for reading the sheet-like object to be read while the sheet-like object to be read is slightly separated from the glass plate surface at the reading position in order to convey the sheet-like object to be read while applying a slight tension to the conveying direction. Since the illuminance on the object to be read is different between the image read using the scanner unit and the image read, there is a disadvantage that the read density is different.

An object of the present invention is to solve the above-mentioned problems of the prior art, and an object of the present invention is to provide a high-quality image reading apparatus and a facsimile apparatus capable of reading an image at an appropriate density. Is to provide.

[0005]

According to the present invention, in order to achieve the above object, an image of an object to be read is received by receiving reflected light from the object to be read illuminated by illumination means. In an image reading apparatus for reading information, the amount of light of the illumination means can be changed.

Accordingly, the object to be read is illuminated with an appropriate illuminance by changing the amount of light of the illumination means.

It is preferable that the illuminating means is an LED, and the amount of light can be changed by changing a load voltage applied to the LED.

[0008] It is preferable to provide a photoelectric conversion means for receiving reflected light from the object to be read and converting the reflected light into a voltage according to the received light.

[0009] The photoelectric conversion means may be a photoelectric conversion element.

It is preferable that the image reading unit is constituted by arranging a plurality of the LEDs and the photoelectric conversion elements linearly in the main scanning direction in the frame.

Therefore, the image reading unit reads the image information of the object to be read by relatively moving the object to be read and the image reading unit in the sub-scanning direction.

It is preferable to provide a plurality of scanning methods for performing scanning while relatively moving the object to be read and the image reading unit, and performing scanning using different relative movement methods.

Therefore, by changing the scanning method according to the object to be read, the image information of the object to be read can be properly read.

Preferably, the light amount of the illumination means is changed according to the different scanning method.

Therefore, by setting the light amount according to each scanning method, the object to be read can be illuminated with appropriate illuminance.

[0016] At least one of the scanning methods is an image reading unit movement for scanning by fixing an object to be read at a predetermined position and moving the image reading unit relatively to the object to be read. It is preferable to use a scanning method.

Therefore, when reading the image information of an object to be read having a thickness such as a book, the reading is performed by the image reading unit moving scanning method.

[0018] At least one of the scanning methods is a method of moving an object to be scanned by fixing the image reading unit at a predetermined position and moving the object to be scanned relative to the image reading unit. It is preferable to use a scanning method.

Therefore, when the object to be read has a thin sheet shape, and particularly when a plurality of pieces of image information are continuously read, the reading object moving and scanning method is used.

It is preferable that the light amount of the illuminating means is higher in the case of scanning using the moving object scanning method than in the case of scanning using the image reading unit moving scanning method.

Accordingly, in the case of the object scanning method, the object is read at a position where the object to be read is farther from the image reading unit than in the case of the image scanning unit moving scanning method. Are illuminated with appropriate illuminance because the light amount is higher.

The position for setting the object to be read is different between the case where the image reading unit moving scanning method is used and the case where the object scanning method is used.
It is preferable to provide a detecting unit for detecting at which position the object to be read is set, and to switch the light amount of the illumination unit according to the detection result of the detecting unit.

Therefore, the detection means detects which method is used for scanning, and the image information is read with an appropriate amount of light.

It is preferable that the facsimile apparatus is provided with the above image reading apparatus.

[0025]

Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, the dimensions of the components described in this embodiment,
The material, shape, relative arrangement, and the like are not intended to limit the scope of the present invention only to them unless otherwise specified.

FIGS. 1, 2 and 3 are external perspective views of the entire facsimile apparatus according to the embodiment of the present invention.
FIG. 4 is an overall sectional view of the facsimile apparatus according to the embodiment of the present invention. FIG. 5 is a block diagram showing the configuration of the facsimile apparatus according to the embodiment of the present invention. FIG. 6 is a cross-sectional view in the sub-scanning direction showing a facsimile apparatus according to the embodiment of the present invention, in particular, an image reading unit. FIG. 7 is a sectional view in the main scanning direction of the image reading device according to the embodiment of the present invention, and FIG. 8 is a flowchart showing a reading operation of the facsimile apparatus according to the embodiment of the present invention.

[General Description of Facsimile Apparatus] In FIGS. 1, 2, 3 and 4, reference numeral 130 denotes a flatbed scanner for reading an image of a document B as an object to be read placed on a platen glass 130a. And 10
Reference numeral 2 denotes a pressure plate that opens and closes around opening and closing fulcrums a and b, and opens and sets the original D on the original platen glass 130a.
When the document is closed, the document D can be brought into close contact with the document table glass 130a. Reference numeral 108 denotes a contact image sensor as an image reading unit that reads an image.

An upper surface of the pressure plate 102 is provided with an original placing table 102b on which a plurality of originals S can be stacked. 1
Reference numeral 06 denotes a document separating / conveying unit which is provided in the pressure plate 102 and separates and conveys the originals S stacked on the original placing table 102b one by one. The sheet reading unit 107 reads the original image while conveying the original. . Reference numeral 109 denotes a document discharge tray on which the discharged documents are stacked.

Reference numeral 104 denotes a laser beam scanner 110
A laser beam printer, which is a recording unit of an electrophotographic system using a printer, 111 is an image forming unit for transferring an image to recording paper, and 112 is a recording beam from a plurality of recording papers stacked and stored in a box-shaped paper cassette. A cassette paper feed unit that separates and conveys one sheet at a time toward the image forming unit; 125 is a manual feed unit that separates and conveys one sheet at a time from the plurality of recording sheets placed on the recording sheet tray to the image forming unit; Paper feeder,
Reference numeral 116 denotes a fixing unit that fixes the image transferred to the recording paper by the image forming unit 111 to the recording paper, 117 denotes a pair of paper discharge rollers, and 113 denotes a recording paper discharge tray on which the discharged recording paper is stacked.

Reference numeral 105 denotes an operation unit for performing display, input, and the like. Reference numeral 120 denotes a control unit for electrically controlling the entire apparatus such as reading and recording, communication, and operation. Reference numeral 121 supplies DC power to each unit of the apparatus. DC power supply.

Next, in FIG. 5, B100 is a system controller for controlling the overall electric system of the facsimile machine, and B101 is a power supply for supplying power to each section of the machine. A plug B102 for taking commercial power from an outlet is connected to the power supply B101.

A reading unit B110 performs reading in the facsimile machine. B111 is a photoelectric conversion element as photoelectric conversion means built in the contact type image sensor, and converts image information of an object to be read into an electric signal. B112 denotes an analog image processing unit that performs analog image processing on an analog signal output from the photoelectric conversion element B111, and B113 denotes an analog image processing unit B112.
A that converts the analog signal processed in step 1 into a digital code
/ D converter. B114 is A / D converter B
A digital image processing unit that performs digital processing on the image information digitally encoded in 113, and has a function of optimally correcting a halftone image. B115 is a light emitting element as illumination means incorporated in the contact type image sensor together with the photoelectric conversion element, and is a light source for illuminating the object to be read. B116 is a driver for electrically driving the light emitting element B115. Reference numeral B117 denotes a CS carriage motor that moves a contact type image sensor having a photoelectric conversion element B111, a light emitting element B115, and the like in the reading unit B110 in the flatbed scanner.
Reference numeral 8 denotes a document transport motor that transports a sheet-like read target. B119 is a CS carriage motor B117
And a motor driver for electrically driving the document conveying motor B118, and a sensor B120 for detecting the operation of each unit in the reading unit B110.

A recording unit B130 performs recording in the facsimile apparatus. In the present embodiment, the recording unit is a laser beam printer that generates an image on an object to be read by an electrophotographic method using a laser beam. Reference numeral B140 denotes an operation unit for performing various operations.
An LCD driver that electrically drives the LCD 42, a key switch of an input unit, and the like are provided. B150 is a communication unit for exchanging image information and the like with other facsimile apparatuses and the like, and modulates the frequency of a signal generated in the apparatus into a signal in a frequency band usable in a public telephone line and performs other facsimile apparatuses. MODEM that demodulates the signal sent from
B151 and an NCU B152 for controlling connection between the facsimile machine and the subscriber telephone line. B153 is a public telephone line.

[Description of Contact Image Sensor as Image Reading Unit Constituting Image Reading Apparatus] The contact image sensor 108 as an image reading unit will be described with reference to FIG. A contact image sensor (same as CS, which is an abbreviation of a contact image sensor in this specification) 108 includes an LED array 108a that illuminates the reading surface of the document, and light reflected from the reading surface of the document. Lens array 108b that forms an image on the sensor, and the light receiving element 1 that is provided immediately below each lens and is a sensor that photoelectrically converts the reflected light that has been formed.
08c is arranged in the frame in a straight line in the main scanning direction, so that one line of the image of the document can be read without relatively moving the document and the sensor. A straight line direction in which the original and the sensor can be read without relatively moving the sensor is referred to as a main scanning direction, and is a direction perpendicular to the paper surface in FIG. In order to read the image of the document two-dimensionally, while reading in the main scanning direction, the contact type image sensor 108 and the document are moved in the sub-scanning direction which is parallel to the document surface and perpendicular to the main scanning direction. Move relatively.

The selfoc lens 108b of the contact type image sensor 108 used for the flatbed scanner 130 of the facsimile apparatus of the present embodiment is a long focal type, and the platen glass 130 having a thickness of 3 [mm].
The focus is set on the original mounting surface a.

[Explanation of Scanning and Reading Images by Image Reading Unit Moving System] Referring to FIGS. 3, 4, 6 and 7, it is used when scanning and reading images by the image reading unit moving system. The flatbed scanner unit 130 to be used will be described. The flatbed scanner unit 130 reads a thick original B such as a book in a stationary state, and 130a is a platen glass on which the original B is placed. The platen glass 130a is a glass plate having a thickness of 3 [mm], and has a document placing area and a sheet reading area in the sheet reading unit 107.

An index 130f indicating the position of the original B on the original glass 130a is provided on the original B mounting surface of the original glass 130a between the original mounting area and the sheet reading area.
Is pasted. The index 130f has a thickness of 0.5 [m
m], and the surface in contact with the platen glass 130a is
This is a white reference for setting a reference white level before reading an image of a document. Reference numeral 130b denotes a frame of the flatbed scanner unit 130, which is a supporting structure such as a platen glass 130a. 130c is a guide shaft when the contact type image sensor 108 moves within the frame 130b, and is attached to the frame 130b. 130d is the guide shaft 130
c is a CS carriage that moves the close contact type image sensor 108 along c, and is attached to a guide shaft 130c via a bearing 130e.
The contact image sensor 108 is mounted on the platen glass 130a.
It is attached so as to urge the surface.

Reference numeral 102e denotes a three-layer document holding plate having a sponge having a thickness of about 5 [mm] interposed between a white plastic film in contact with the document B and a metal plate serving as a base. In addition, it is supported so that it can move up and down with respect to the pressure plate 102, and by closing the pressure plate 102,
Original B on original platen glass 130a is moved to original platen glass 130
Press against a.

Here, the pressure plate 102 is provided with rotating fulcrum portions (hereinafter referred to as hinges) 102f and 102g on a frame 130.
b, and the pressure plate 102 is
0b can be opened and closed by a predetermined angle. The user can open and close the pressure plate 102 to place and remove a document on the platen glass 130a.

The contact type image sensor 108 detects the original B
In order to read the reading surface two-dimensionally, it is moved by a driving unit (not shown) along the guide shaft 130c in the sub-scanning direction (the direction of the arrow A in the drawing) which is a direction perpendicular to the main scanning direction. The contact image sensor 108 is urged against the surface of the platen glass 130a opposite to the surface on which the document is placed, and moves in the sub-scanning direction by the above-described driving means. Distance is always kept constant. As a result, the height of the focal position of the contact image sensor 108 on the platen glass 130a becomes constant, and a good image without a focal position shift can be obtained.

[Explanation of the case where an image is read by scanning the object to be read / scanning method] When the image is read by scanning the object to be read / moving and scanning method with reference to FIGS. 4, 6, and 7, FIG. The document transport unit 106 and the sheet reading unit 107 used will be described. Document transport unit 106
, The document S loaded on the document table 102b
First, the preliminary transport roller 102d and the preliminary transport pressing plate 10
2c, the separation roller 106b and the separation roller 10
The separation roller 106b and the separation piece 106a are fed one by one by the separation roller 106b and the separation piece 106a. The originals S separated one by one are fed to the feeding roller 1.
06e and the feed roller 10 pressing the feed roller 106e
6f, the sheet is conveyed toward the sheet reading unit 107. Immediately before the sheet reading unit 107, a document edge detection sensor 107b
The reading start position and the reading end position are set in accordance with the length of the document S by detecting the leading and trailing ends of the document S in the transport direction.

Reference numeral 107a denotes a sheet reading unit 107
A document pressing roller for assisting the conveyance while the document S is in contact with the surface of the platen glass 130a, and receives a rotational driving force from a driving system (not shown). Document holding roller 10
7a are bearings 107c and 10 arranged at both ends of the central shaft.
7d rotatably supports. Here, the bearings 107c and 107d are in pressure contact with the platen glass 130a, and with respect to the radius r of the document pressing roller 107a,
The distance I from the center of rotation of the bearing to the surface of the platen glass 130a is larger. Therefore, the bearing 107c,
In a state where 107d is pressed against the platen glass, the document pressing roller 107a is not in contact with the platen glass 130a. In the present embodiment, the original pressing roller 10
A gap distance δ (=
Ir) is set to 0.2 [mm].

The document that has passed through the sheet reading unit 107 is discharged to a document discharge tray 109 by a document discharge roller 106g and a document discharge roller 106h.

When reading the original S, the contact image sensor 108 is set in advance under the original pressing roller, and the original S is kept stationary with respect to the flatbed scanner unit 130. Read the image while transporting. For this purpose, the document conveying speed Vi between the feeding roller 106e and the feeding roller 106f is used.
Is synchronized with the reading speed of the contact image sensor 108.

At this time, by setting the document conveyance speed Vo of the document discharge roller 106g and the document discharge roller 106h slightly higher than Vi, the document S is moved between the feed roller 106e and the document discharge roller 106g. Is applied to the sheet reading unit 107 so that the document S is not slackened. Further, the original pressing roller 107a, which is arranged to protrude toward the original conveying path from the tangent line between the outer periphery of the feeding roller 106e and the outer periphery of the original discharge roller 106g, is provided by the original pressing roller 10 which is pressed against the original platen glass 130a.
The bearing portion 7a has a pressing force enough to prevent the document S from floating from the platen glass 130a due to the pulling force applied to the document S.

Therefore, the thickness of the original S is set so that the thickness t of the original S is equal to the outer peripheral surface of the original pressing roller 107a and the original table glass 130.
When the gap S is smaller than the gap distance δ, the document is conveyed while being in contact with the rotating original pressing roller 107a at a constant gap distance δ. Reading is performed in a state where the document is separated from the document placing surface 130a.

Since the original transport unit 106 is provided in a part of the pressure plate 102, when the pressure plate 102 is opened with respect to the flatbed scanner unit 130, the original transport unit 1
Reference numeral 06 also opens integrally with the pressure plate 102, and can easily release the document conveying path in the event of a document jam or the like.

Sliders 102a slidable in a direction perpendicular to the conveying direction of the document S (the width direction of the document S) are provided on both sides of the document mounting table 102b in the width direction of the document S. The document S placed on the document S can be aligned on both sides. Although not shown, it is electrically determined whether or not the original S is set at a position where the original S is placed on the original mounting table 102b and can be preliminarily conveyed by the preliminary conveyance roller 102d and the preliminary conveyance pressing plate 102c. An original detection sensor is provided as a detection unit for detecting.

[Explanation of the operation of changing (switching) the amount of light of the illuminating means and the operation of reading image information, which are features of the image reading apparatus according to the embodiment of the present invention] Referring to FIG. 6 and FIG. The operation of changing (switching) the light amount and the reading operation will be described. In the present embodiment, the illumination means is an LED, and the amount of light is changed by changing the load voltage on the LED.

First, when the reading operation is started at F00, the contact type image sensor (CS) 108 is started at F01.
Is the index 1 attached to the platen glass 130a.
The white reference is illuminated by moving to the white reference position on the rear surface of 30f and lighting the LED incorporated in the contact image sensor (CS) 108 at a predetermined voltage Vb at F02. In F03, a white reference level is set based on the output of the contact image sensor (CS) 108 due to the reflected light from the white reference.

Next, at F04, the original table 102 is detected by the original detection sensor provided in the original transport section 106.
It is determined whether the document S is set on b. here,
If it is determined that the document S is set, the process proceeds to F20 assuming that scanning is to be performed by the scanning method of the object to be read, and if it is determined that the document S is not set, scanning is performed by the image reading unit moving method. F1 as a thing
Go to 0.

If it is determined that the original S is set, first, at F20, the contact type image sensor (CS) 1
08 is moved to the sheet reading position of the sheet reading unit 107. When the conveyance of the document S is started in F21, the document S is separated one by one by the document conveyance unit 106, and the sheet reading unit 1
07. In F22, the LED built in the contact image sensor (CS) 108 is turned on with Vs. In F23, the original S conveyed to the sheet reading position is scanned by the contact type image sensor (CS) 108.
Is read line by line, and this is repeated until it is determined in F24 that reading of one document S has been completed.
Subsequently, in F25, similarly to F04, the original table 1 is detected by the original detection sensor provided in the original transport unit 106.
It is determined whether or not the document S remains in the document 02b. If it is determined that the document S remains, the process returns to F21, and F21 to F24 are repeated by the number of the set documents S. Thereby, a plurality of originals S can be continuously read. If it is determined in F25 that there is no original S on the original mounting table 102b, the process proceeds to F26, in which the transport operation of the original S is stopped after the last original S is discharged, and the reading operation is ended in F27.

When it is determined in F04 that the document S is not set, first, the contact type image sensor 108 is moved to the reading start position of the document B in F10. F11
The LED built in the contact type image sensor (CS) 108 is turned on by Vb, and the guide shaft 13 is turned on by F12.
Contact image sensor 1 in the direction guided by Oc
08 (CS) is started. The original B is read line by line by the contact image sensor (CS) 108 in F13, and this is repeated until it is determined in F14 that the reading of the original B is completed. If it is determined in F14 that the reading of the document B has been completed, the process proceeds to F15, in which the movement of the contact image sensor (CS) 108 is stopped, and
Ends the reading operation.

As described above, when the relative distance from the image reading unit to the object to be read is different depending on the scanning method, the illuminance on the object to be read becomes uniform by appropriately changing the light amount of the illuminating means. It is possible to record at an appropriate density.

That is, in the present embodiment, the relative position of the object to be read with respect to the image reading unit is higher when scanning is performed by the scanning method for moving the object to be read than when scanning is performed by the moving scanning method for the image reading unit. The former case is longer than the latter case.
By setting the load voltage to the ED high (Vs> Vb) to increase the light amount of the LED, the illuminance on the object to be read can be made uniform in any of the scanning methods, and the optimum density can be obtained. Can be recorded.

[Description of Recording Unit] The recording unit 104 will be described with reference to FIG. The recording unit 104 is provided at a lower portion of the apparatus, and feeds the paper P from a paper feed cassette 112a in which general-purpose fixed-size paper P is stacked and stored.
b, one sheet at a time is transported separately.
After correcting the skew of the sheet P, the sheet P is fed to the image forming section 111 in synchronization with a control signal from the control section 120. In the image forming unit 111, first, the photosensitive drum 111 serving as an electrostatic latent image carrier is charged by the charging member 111b.
The surface of a is uniformly charged, and the surface is scanned by a laser beam scanner 110 and exposed according to image information. As a result, an electrostatic latent image is formed on the photosensitive drum 111a, and when toner as a developer is adhered to the electrostatic latent image on the photosensitive drum 111a by a developing sleeve 111c as a developing carrier, the toner is formed on the photosensitive drum 111a. An image is formed. By transporting the sheet P between the photosensitive drum 111a on which the toner image is formed and the transfer roller 111f, the toner image is transferred to the surface of the sheet P that is in contact with the photosensitive drum 11a, and the sheet P is fixed to the fixing unit 116. Transport toward. The fixing unit 116 applies a fixing roller 116 b and a pressure roller 11 to the toner transferred onto the paper P.
The sheet is conveyed while being fixed by applying heat and pressure to the sheet 6a. The paper P on which the toner image has been fixed is discharged to a recording paper discharge tray 113 by a discharge roller pair 117.

On the other hand, the sheets P stacked on the manual sheet feeding section 125 are separated and conveyed one by one by a separation pad 125b arranged at a position facing the sheet feeding roller 125a, and the skew is corrected by the registration roller pair 124. After that, similarly to the sheet fed from the cassette sheet feeding unit 112, the toner image is transferred by the image forming unit 111, fixed by the fixing unit 116, and discharged to the recording sheet discharge tray 113.

[0058]

According to the present invention, the object to be read is illuminated with an appropriate illuminance by changing the amount of light of the illuminating means, so that image information can be read with an appropriate density and excellent in quality.

The image reading unit is constituted by arranging a plurality of LEDs and photoelectric conversion elements linearly in the main scanning direction in the frame, whereby the object to be read and the image reading unit are relatively moved in the sub scanning direction. By doing so, the image reading unit can read the image information of the object to be read.

By providing a plurality of scanning methods for scanning by different relative movement methods, it is possible to appropriately read the image information of the object to be read by changing the scanning method according to the object to be read.

By setting the light amounts according to the different scanning methods, it is possible to properly read the image information of the object to be read.

Since the object to be read is read at a position where the distance of the object to be read is farther from the image reading unit than to the moving and scanning method of the image reading unit than in the case of the moving and scanning method of the image reading unit. Has a high light intensity,
Since the image is illuminated with an appropriate illuminance, image information can be read at an appropriate density.

The detection means can detect which method is used for scanning, and the illumination is performed with an appropriate illuminance, so that image information can be read with an appropriate density.

A facsimile machine can be provided with the above image reading device.

[Brief description of the drawings]

FIG. 1 is an external perspective view of a facsimile apparatus according to an embodiment of the present invention.

FIG. 2 is an external perspective view of the facsimile apparatus according to the embodiment of the present invention in a state where a paper discharge tray is removed.

FIG. 3 is an external perspective view of the facsimile apparatus according to the embodiment of the present invention with a pressure plate opened.

FIG. 4 is an overall sectional view of the facsimile apparatus according to the embodiment of the present invention.

FIG. 5 is a block diagram showing the overall configuration of the facsimile apparatus according to the embodiment of the present invention.

FIG. 6 is a cross-sectional view in the sub-scanning direction of an image reading device provided in the facsimile apparatus according to the embodiment of the present invention.

FIG. 7 is a cross-sectional view in the main scanning direction of an image reading device provided in the facsimile apparatus according to the embodiment of the present invention.

FIG. 8 is a flowchart showing a reading operation of the image reading device provided in the facsimile apparatus according to the embodiment of the present invention.

[Explanation of symbols]

 102 Pressure plate 104 Recording unit 105 Operation unit 106 Document transport unit 107 Sheet reading unit 107a Document pressing roller 107b Document edge detection sensor 107c, 107d Bearing 108 Contact image sensor 108a LED array 108b Selfoc lens 108c Light receiving element 109 Document ejection tray 110 Laser scanner 111 Image forming unit 112 Cassette feeding unit 113 Recording paper discharging unit 116 Fixing unit 117 Paper discharging roller pair 120 Control unit 124 Register roller pair 125 Manual paper feeding unit 130 Flatbed scanner unit 130a Document table glass 130b Frame 130c Guide Shaft A Main scanning direction B Book document D Sheet document transport direction P Recording paper R Recording paper transport direction S Sheet document δ Distance between document pressing roller and platen glass Separation

Claims (12)

[Claims] 1. An image reading apparatus for reading image information of an object to be read by receiving reflected light from the object to be read illuminated by an illumination means, wherein a light amount of the illumination means can be changed. An image reading apparatus comprising: 2. The image reading apparatus according to claim 1, wherein said illuminating means is an LED, and a light amount can be changed by changing a load voltage to said LED. 3. The image reading apparatus according to claim 1, further comprising: photoelectric conversion means for receiving reflected light from the object to be read and converting the reflected light into a voltage according to the received light. 4. An image reading apparatus according to claim 3, wherein said photoelectric conversion means is a photoelectric conversion element. 5. The image reading device according to claim 4, wherein an image reading unit is configured by arranging a plurality of the LEDs and the photoelectric conversion elements linearly in a main scanning direction in a frame. 6. A system for scanning while relatively moving the object to be read and the image reading unit, wherein a plurality of scanning systems for scanning by different relative movement methods are provided. Item 6. The image reading device according to Item 5. 7. An image reading apparatus according to claim 6, wherein the light amount of said illumination means is changed according to said different scanning method. 8. An image reading method according to claim 1, wherein at least one of said scanning methods scans by fixing an object to be read at a predetermined position and moving said image reading unit relatively to said object to be read. 7. The image reading apparatus according to claim 6, wherein the apparatus is of a unit moving scanning type. 9. At least one of the scanning methods includes an object to be scanned which is scanned by fixing the image reading unit at a predetermined position and relatively moving the object to be scanned with respect to the image reading unit. 7. The image reading apparatus according to claim 6, wherein the image reading apparatus uses an object movement scanning method. 10. The light amount of said illuminating means is higher when scanning using said object to be read moving scanning method than when scanning using said image reading unit moving scanning method. Item 10. The image reading device according to Item 9. 11. A position for setting an object to be read is different between a case where the image reading unit movement scanning method is used and a case where the object movement scanning method is used. 11. The image reading apparatus according to claim 10, further comprising detecting means for detecting whether the light is set, and switching an amount of light of the illuminating means according to a detection result of the detecting means. 12. A facsimile apparatus comprising the image reading device according to claim 1.