JP2004258386A - Original size detecting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an original size detecting device capable of detecting an original size in a state where an original cover is open at a low angle and diffused external light hardly enter, and also, capable of making the original size detection resistant to the diffused external light, and also, capable of detecting the original size after returning the power source of an original size detection sensor etc., from a usual OFF state to an ON state at the time of detecting the original size in order to save energy and prolong the life. <P>SOLUTION: The original size detecting device is provided with the original cover 112 for pressing the original 101 placed on an original platen 102, a light source 103 for irradiating the original with light, a CCD 110 for reading light reflected by the original after being emitted from the light source, and optical sensors 113 and 114 for detecting the open state of the original cover at least by two steps, and a prescribed control corresponding to the open state of the original cover detected by the optical sensor is performed, and then, the original size is discriminated based on the reading result of the CCD. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a document size detecting device for detecting a size of a document to be read in a digital copying machine, a scanner device, a facsimile device, or the like.
[0002]
[Prior art]
Conventionally, there are various types of document size detecting devices for detecting the size of a document to be image-read, but the leading end of the document is illuminated by a light source, and reflected light from the document is charged by a CCD (electric charge). A document size detection sensor that reads the document size in the sub-scanning direction and detects the document size in the sub-scanning direction, and detects the document size based on the reading result of the CCD and the detection result of the document size detection sensor. It is known (for example, see Patent Document 1).
[0003]
As described above, by detecting the document size using the CCD for reading the document only in the main scanning width detection, the number of document size detection sensors can be reduced, and the cost-effective and efficient document size detection can be performed. Can be.
[0004]
As another method, the size of a document is determined by detecting whether the document pressure plate that presses the document to be read on the upper surface of the document table is opened and closed, and detecting the open state of the document pressure plate. A detection method is also known (for example, see Patent Document 2).
[0005]
However, in any of the above-described conventional examples, the detection of the basic document size is possible, but when reading the reflected light from the document, the light from the device other than the document size detecting device, such as the light of the room light, is used. Since the disturbance light is also read at the same time, and it is not possible to distinguish the disturbance light from the reflected light from the document, there is a problem that the document size may be erroneously detected.
[0006]
In order to prevent the influence of such disturbance light, a method of detecting the document size when the document pressure plate is closed, for example, a method of reducing the density of the back surface of the document pressure plate to detect a white document is known. It is known (for example, see Patent Document 3).
[0007]
[Patent Document 1]
JP-A-5-207239
[Patent Document 2]
JP-A-9-329848
[Patent Document 3]
JP-B-62-47026
[0008]
[Problems to be solved by the invention]
However, in the above-described conventional method of lowering the density of the back surface of the original pressure plate to detect a white original, the original size can be detected, but the background of the original becomes dark when reading the original. Occurs. This show-through phenomenon becomes remarkable when reading an original having a high transmittance, such as a second original draft original, and there is a problem that reading is hindered.
[0009]
SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems of the related art, and an object of the present invention is to detect a document size in a state where an opening angle of a document pressure plate is low and disturbance light is hard to enter. It is possible to detect a document size that is resistant to disturbance light and to return to the on state when the document size is detected from the state where the power supply of the document size detection sensor is normally turned off for energy saving and prolonging the service life. An object of the present invention is to provide a document size detecting device capable of detecting a size.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, a document size detection device according to the present invention includes a document pressure plate for pressing a document placed on a document table, a light source for irradiating the document with light, and a light source for irradiating the document with the light source. Reflected light reading means for reading the reflected light of the reflected light, and open state detecting means for detecting the open state of the document pressure plate in at least two stages, wherein the open state of the document pressure plate detected by the open state detection means is detected. A predetermined control corresponding to a state is performed, and the size of the document is determined based on a reading result of the reflected light reading unit.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0012]
(First Embodiment)
First, a first embodiment of the present invention will be described with reference to FIGS.
[0013]
FIG. 1 is a schematic front view showing a configuration of an image reading system in an image reading apparatus to which the document size detecting device according to the present embodiment is applied, FIG. 2 is a side view thereof, and FIG. FIG. 3 is a plan view showing a configuration of a document table of the image reading apparatus to which the document size detection device according to the embodiment is applied.
[0014]
The image reading apparatus shown in FIGS. 1 to 3 is a general digital image reading apparatus.
[0015]
1 and 2, reference numeral 101 denotes a document, reference numeral 102 denotes a document table, reference numeral 103 denotes a light source (lamp), reference numeral 104 denotes a first mirror, reference numeral 105 denotes a first optical table, reference numerals 106 and 107 denote second and third mirrors, 108 is a second optical bench, 109 is a lens, 110 is a CCD (charge coupled device), 111 is a document size detection sensor (reflection type sensor), 112 is a document pressure plate, 113 and 114 are optical sensors, 115 is a sensor flag, 116 is a housing.
[0016]
The document mounting table 102 mounts the document 101 to be read, and is made of transparent glass. The light source 103 irradiates light to the surface of the document 101 placed on the document table 102. The first mirror 104 reflects light reflected from the document 101 toward the second mirror 106. The first optical bench 105 houses the light source 103 and the first mirror 104. The second and third mirrors 106 and 107 reflect light from the first mirror 104 and guide the light to the lens CCD 110. The second optical table 108 houses the second and third mirrors 106 and 107. The lens 109 focuses the light from the third mirror 107 on the CCD 110. The CCD 110 converts an optical signal input through the lens 109 into an electric signal. The document size detection sensor 111 detects the size of the document 101 placed on the document placing table 102 in the sub-scanning length direction, and outputs a binary value indicating the presence or absence of the document 101 on the document placing table 102.
[0017]
The document pressure plate 112 presses the document 101 against the upper surface of the document table 102. The back surface of the document pressure plate 112 is white in order to prevent show-through when reading the document 101. The optical sensors 113 and 114 detect the opening angle of the document pressing plate 112 in two stages. The sensor flag 115 moves up and down according to the opening angle of the document pressure plate 112, and when the angle reaches a predetermined angle, the light of the optical sensors 113 and 114 is blocked, whereby the opening angle of the document pressure plate 112 is detected by the optical sensors 113 and 114. . The housing 116 includes a document table 102, a light source 103, a first mirror 104, a first optical table 105, second and third mirrors 106 and 107, a second optical table 108, a lens 109, a CCD 110, and a document size. A detection sensor 111, a document pressure plate 112, optical sensors 113 and 114, and a sensor flag 115 are mounted.
[0018]
As shown in FIG. 3, a document size label 301 is provided on an outer peripheral portion of the document placing table 102, and a document alignment mark 302 is provided on a rear side reference abutting portion shown at the upper left of FIG. A document of a standard size (A3, A4, A5, A4R, B4, B5, B5R, B6) is placed as shown in FIG.
[0019]
The original 101 is read by using the image reading apparatus having the above configuration.
[0020]
FIG. 4 is a block diagram showing a configuration of a control system of an image reading apparatus to which the document size detecting device according to the present embodiment is applied.
[0021]
As shown in FIG. 4, a control system of the image reading apparatus includes a light source (lamp) 103, a CCD 110, a document size detection sensor 111, optical sensors 113 and 114, an A / D conversion circuit 401, an optical motor 402, and a scanner controller 403. And a display unit 404.
[0022]
The CCD 110 receives the reflected light from the document surface as described above, and reads the document 101. The A / D conversion circuit 401 converts the output signal of the CCD 110 from analog to digital. The optical motor 402 scans the document 101 by moving the first optical bench 105 and the second optical bench 108. The light source 103 irradiates light to the document surface as described above. The document size detection sensor 111 detects the size of the document 101 in the sub-scanning length direction as described above. The optical sensors 113 and 114 detect the opening angle of the document pressure plate 112 at 40 ° and 15 °, respectively. The display unit 404 displays information indicating the detection result of the document size.
[0023]
The scanner controller 403 controls the CCD 110, the optical motor 402, the light source 103, and the document size detection sensor 111, and starts the document size detection operation based on the detection result of the opening angle of the document pressure plate 112 by the optical sensors 113 and 114. The length of the document 101 in the main scanning direction is detected from the digital signal output from the D conversion circuit 401. Further, the size of the document 101 in the sub-scanning length direction is detected by the document size detection sensor 111. The detection result of the size of the document 101 in the main scanning direction and the detection result of the size in the sub-scanning length direction are entangled to determine the size of the document 101, and information indicating the document size result is displayed on the display unit 404. To be displayed. Further, the scanner controller 403 executes a document size detection process shown in a flowchart of FIG. 12 (first embodiment) and FIG. 17 (second embodiment), which will be described later.
[0024]
FIG. 5 is a plan view showing detection points used for determining the size of the document 101 on the document table 102 of the image reading apparatus to which the document size detecting device according to the present embodiment is applied. By arranging the document size detection sensor 111 for detecting the size in the document sub-scanning length direction at the detection point shown in the drawing, the first optical table 105 is placed on the document only for the size of each portion of the document in the main scanning length direction. It is arranged at a position shown in the drawing on the table 102 and reading is performed by the CCD 110.
[0025]
The correspondence between each component in the claims of the present invention and each unit in the present embodiment is as follows.
[0026]
The reflected light reading means corresponds to the CCD 110, the light source corresponds to the lamp 103, the document size determining means corresponds to the scanner controller 403, the document pressure plate corresponds to the document pressure plate 112, and the pressure plate opening / closing angle detecting means corresponds to the optical sensor 113. The sub-scanning detection unit corresponds to the document size detection sensor 111.
[0027]
Next, a document size detection operation in the image reading apparatus to which the document size detection device according to the present embodiment configured as described above is applied will be described with reference to FIGS.
[0028]
As shown in FIG. 6, a description will be given of a document size detecting operation when an external light source, for example, a fluorescent lamp 601 is provided above the image reading apparatus.
[0029]
In order to easily understand the effect of the present embodiment, first, assuming that one of the optical sensors 113 is not provided, a conventional document size detection method in a case where the opening angle of the document pressure plate 112 can be detected at only one position is described. The problem will be described with reference to FIG.
[0030]
FIG. 7 is a flowchart showing the flow of a document size detection operation in the conventional document size detection method.
[0031]
First, in step S701, the scanner controller 403 of the image reading device checks the state of the optical sensor 114. If the opening angle of the document pressure plate 112 is 40 ° or more, the power of the light source 103, the CCD 110, and the document size detection sensor 111 is turned off in step S702 for energy saving, and the process returns to step S701.
[0032]
Next, in step S701, when the optical sensor 114 detects that the opening angle of the document pressure plate 112 has changed from 40 ° or more to 40 ° or less, in step S703, the scanner controller 403 determines whether the document pressure plate 112 It is determined that the user has started to close, and the power sources of the light source 103, the CCD 110, and the document size detection sensor 111 are turned on. Next, in step S704, after waiting for each device to stabilize, the document size detection sensor 111 is controlled. In step S705, the presence or absence of the document 101 and the size of the document 101 in the sub-scanning length direction are determined based on the binary output signal of the document size detection sensor 111. In step S706, the light source 103 is turned on, and the The main scanning direction information is read by the CCD 110. Next, in step S707, the scanner controller 403 reads the output signal of the CCD 110 as a digital signal from the A / D conversion circuit 401, and determines the presence or absence of reflected light from the document 101 based on a preset threshold. If it is determined that there is reflected light, in step S708, it is determined that a point with reflected light is present. The reading result at this time is shown in FIG.
[0033]
Thereafter, in step S709, the scanner controller 403 determines the document size based on the sub-scanning length direction determination by the document size detection sensor 111 and the main scanning determination result by the CCD 110 as shown in FIG. Is displayed on the display unit 404 in order to inform the user of this, the processing operation ends.
[0034]
On the other hand, if it is determined in step S707 that there is no reflected light, the process proceeds to another process.
[0035]
In such a conventional document size detection method, since the document size is detected while the opening angle of the document pressure plate 112 is high, disturbance light from the fluorescent lamp 601 enters the shaded portion 901 in FIG. I understand.
[0036]
In order to prevent such erroneous detection, if the opening angle of the document pressure plate 112 is set to a low angle, for example, 15 °, the power of the light source 103, the CCD 110, and the document size detection sensor 111 is turned on, and the apparatus waits until each device is stabilized. When the apparatus user quickly closes the document pressure plate 112, the document size detection operation is performed after the document pressure plate 112 is completely closed as shown in FIG. 10, so that the light source 103 is turned on and the document surface main scanning is performed. When the size information in the direction is read by the CCD 110 as shown in FIG. 11, the white on the back surface of the original pressure plate 112 and the white of the original 101 cannot be separated as in the case where the disturbance light enters. There was a problem.
[0037]
Next, a detection operation of the document size detection device according to the present embodiment for solving these problems will be described with reference to a flowchart of FIG.
[0038]
First, in step S1201, the scanner controller 403 of the image reading apparatus checks the states of the optical sensors 113 and 114. If the opening angle of the document pressure plate 112 is equal to or greater than 40 °, the power of the light source 103, the CCD 110, and the document size detection sensor 111 is turned off for energy saving in step S1202, and the process returns to step S1201.
[0039]
Next, in step S1201, when the optical sensors 113 and 114 detect that the opening angle of the document pressure plate 112 has changed from 40 ° to 15 °, in step S1203, the scanner controller 403 closes the document pressure plate 112. It is determined that the operation has started, and the power of the light source 103, the CCD 110, and the original size detection sensor 111 is turned on in preparation for detecting the original size.
[0040]
Next, in step S1204, the scanner controller 403 checks the states of the optical sensors 113 and 114. Then, when detecting that the opening angle of the document pressure plate 112 has changed from 40 ° to 15 ° or less, in step S1205, the document size detection sensor 111 is controlled, and a binary output signal of the document size detection sensor 111 is output. The presence or absence of the document and the size of the document in the sub-scanning length direction are determined based on the document. Next, in step S1206, the scanner controller 403 turns on the light source 103 and reads the size information of the document in the main scanning length direction by the CCD 110.
[0041]
Next, in step S1207, the scanner controller 403 reads the output signal of the CCD 110 as a digital signal from the A / D conversion circuit 401, and determines the presence or absence of reflected light from the document 101 based on a preset threshold. If it is determined that there is reflected light, in step S1208, it is determined that the point with reflected light is present. The reading result at this time is shown in FIG.
[0042]
Thereafter, in step S1209, the scanner controller 403 determines the size of the document as shown in FIG. 14 based on the size determination result in the sub-scanning length direction by the document size detection sensor 111 and the size determination result in the main scanning length direction by the CCD 110. The size is determined, and information indicating the determination result is displayed on the display unit 404 to notify the user of the determination result. At this time, the read value from the CCD 110 is obtained when the opening angle of the original platen 112 is 15 ° as shown in FIG. Since the disturbance light does not enter, accurate document size detection is possible. Since the document size detection preparation processing is performed when the opening angle of the document pressure plate 112 starts to close from 40 ° or more, the document size detection operation is immediately performed when the opening angle of the document pressure plate 112 becomes 15 °. Can be performed.
[0043]
If it is determined in step S1207 that there is no reflected light, the process proceeds to another process.
[0044]
As described above, according to the document size detection apparatus according to the present embodiment, as shown in FIG. 3, the document size label 301 is disposed on the outer peripheral portion, and the document alignment mark 302 is provided on the rear reference abutting portion. The original mounting table 102, a light source 103 for irradiating the original 101 on the original mounting table 102 with light, a CCD 110 for reading the image of the original 101 on the original mounting table 102, and the upper surface of the original mounting table 102 To the output of the CCD 110 which reads the original surface by turning on the light source 103 according to the state of the optical sensors 113 and 114, and the state of the optical sensors 113 and 114. A scanner controller 403 for controlling the size of the document 101 on the document table 102 based on the document table 102; Because you are configured to include a display unit 404 for transmitting the over exhibits the actions and effects as described below.
[0045]
In the above configuration, the scanner controller 403 detects the two-stage opening angle of the document pressure plate 112 based on the state of the optical sensors 113 and 114, and performs light source 103, CCD 110, document The power of the size detection sensor 111 is turned on. Next, after determining the size of the document 101 in the sub-scanning length direction in the opening angle range of the second stage of the document pressure plate 112, the presence or absence of reflected light from the document 101 is determined based on a preset threshold value. The point with reflected light is determined to be the document.
[0046]
Therefore, in the document size detecting apparatus according to the present embodiment, it is possible to detect the document size at an optimal angle with a low opening angle of the document pressure plate 112 in accordance with the closing operation of the document pressure plate 112 performed by the user. Therefore, accurate document size detection can be performed while reducing erroneous detection due to disturbance light.
[0047]
(Second embodiment)
Next, a second embodiment of the present invention will be described with reference to FIGS.
[0048]
Note that the basic configuration of the image reading apparatus to which the document size detecting device according to the present embodiment is applied is the same as that of FIG. 1 in the above-described first embodiment. It will be explained.
[0049]
FIG. 16 is a schematic side view showing a configuration of an image reading system in an image reading apparatus to which the document size detecting device according to the present embodiment is applied. The same parts as those in FIG. 2 are denoted by the same reference numerals.
[0050]
16 differs from FIG. 2 in that the optical sensor 1601 is added to the configuration of FIG. 2 so that the opening angle of the document pressure plate 112 can be detected in three steps (for example, 40 °, 25 °, and 15 °). It is added. The other components are the same as those in FIG. 2 in the first embodiment described above, and a description thereof will be omitted.
[0051]
Next, the document size detecting operation in the image reading apparatus to which the document size detecting device according to the present embodiment configured as described above is applied will be described with reference to FIGS. 1 to 5 and FIGS. 13, 14, 16 and 17. This will be described with reference to FIG.
[0052]
FIG. 17 is a flowchart showing a flow of a document size detecting operation in the image reading apparatus to which the document size detecting device according to the present embodiment is applied.
[0053]
First, in step S1701, the scanner controller 403 of the image reading apparatus checks the states of the optical sensors 113, 114, and 1601. If the opening angle of the document pressure plate 112 is equal to or greater than 40 °, the power of the light source 103, the CCD 110, and the document size detection sensor 111 is turned off in step S1702 for energy saving, and the process returns to step S1701.
[0054]
In step S1701, when the optical sensors 113, 114, and 1601 detect that the opening angle of the document pressing plate 112 has changed from 40 ° or more to a range of 40 ° to 25 °, in step S1703, the scanner controller 4203 It is determined that the document pressure plate 112 has started to be closed, and the power of the light source 103 and the CCD 110, which are devices that take a long time from power-on to stabilization, are turned on in preparation for document size detection. Next, in step S1704, the scanner controller 403 checks the states of the optical sensors 113, 114, and 1601. When the optical sensors 113, 114, and 1601 detect that the opening angle of the document pressure plate 112 has changed from the range of 40 ° to 25 ° to the range of 25 ° to 15 °, in step S1705, from power-on to stabilization. The power of the document size detection sensor 111 which does not take much time is turned on. Next, in step S1706, the scanner controller 403 checks the states of the optical sensors 113, 114, and 1601. If the open angle of the document pressure plate 112 is maintained in the range of 25 ° to 15 °, the power of the document size detection sensor 111 is turned off in step S1707, and the process returns to step S1704.
[0055]
In step S1706, when the optical sensors 113, 114, and 1601 detect that the opening angle of the document pressure plate 112 has changed from 25 ° to 15 ° to 15 ° or less, the process proceeds to step S1708. And determines the presence or absence of the document 101 and the size of the document 101 in the sub-scanning length direction based on the binary output signal of the document size detection sensor 111. Next, in step S1709, the scanner controller 403 turns on the light source 103 and reads the size information of the document surface in the main scanning direction by the CCD 110. Next, in step S1710, the scanner controller 403 reads the output signal of the CCD 110 as a digital signal from the A / D conversion circuit 401, and determines the presence or absence of reflected light from the document 101 based on a preset threshold. If it is determined that there is reflected light, in step S1711, it is determined that the point with reflected light is present. The reading result at this time is shown in FIG.
[0056]
Thereafter, in step S1712, the scanner controller 403 determines the size of the document as shown in FIG. 14 based on the size determination result in the sub-scanning length direction by the document size detection sensor 111 and the size determination result in the main scanning length direction by the CCD 110. After determining the size and displaying information indicating the determination result on the display unit 204 in order to notify the user of the determination result, the processing operation ends.
[0057]
As described above, according to the image reading apparatus to which the document size detecting device according to the present embodiment is applied, the light source 103 that irradiates the document 101 on the document placing table 102 with light, and the light source 103 on the document placing table 102 A CCD 110 for reading an image of the document 101; a document pressure plate 112 for pressing the document 101 against the upper surface of the document table 102; optical sensors 113, 114, 1601 for detecting the opening angle of the document pressure plate 112; , 114, and 1601, the scanner controller 403 performs control to determine the size of the document 101 on the document table 102 based on the output of the CCD 110 that reads the document surface by lighting the light source 103, and displays the determination result. Since the display unit 404 is provided with the display unit 404 that informs the user, the following operations and effects are achieved.
[0058]
In the above configuration, the scanner controller 403 detects the opening angle of the document pressure plate 112 based on the state of the optical sensors 113, 114, and 1601. The power of the light source 103 and the CCD 110, which take time to stabilize, is turned on. Next, in the opening angle range of the second stage of the document pressure plate 112, the power of the document size detection sensor 111 is not turned on until the power is turned on, and then the power of the document size detection sensor 111 is turned on. After determining the size of the document 101 in the sub-scanning length direction within the range, the presence or absence of reflected light from the document 101 is determined based on a preset threshold value. Judge that there is.
[0059]
Therefore, in the present embodiment, even when the power of each device used for document size detection is turned off to save energy, the optimal opening of the document pressure plate 112 in accordance with the stabilization time from when the power of each device is turned on. When the power of each device is turned on at an angle, and the opening angle of the document pressure plate 112 is low and the document size can be detected at the optimum opening angle, it is possible to reduce the occurrence of erroneous detection due to disturbance light, Document size can be detected.
[0060]
(Other embodiments)
It is needless to say that the predetermined document size detection operation performed based on the respective open angle ranges of the document pressure plate 112 is not limited to the above-described first and second embodiments.
[0061]
Further, even if the present invention is applied to a system including a plurality of devices (for example, a host computer, an interface device, a reader, a printer, and the like), a device including one device (for example, a copier, a facsimile device, and the like) May be applied.
[0062]
In addition, a storage medium storing program codes of software for realizing the functions of the above-described embodiments is supplied to a system or an apparatus, and a computer (or CPU, MPU, or the like) of the system or the apparatus is stored in the storage medium. It goes without saying that the present invention is also achieved by reading and executing the program code.
[0063]
In this case, the program code itself read from the storage medium realizes the functions of the above-described embodiment, and the storage medium storing the program code constitutes the present invention.
[0064]
Further, as a storage medium for supplying the program code, for example, RAM, NV-RAM, floppy (registered trademark) disk, hard disk, optical disk, magneto-optical disk, MO, CD-ROM, CD-R, CD-RW , A DVD (DVD-ROM, DVD-R, DVD-RW, etc.), a magnetic tape, a non-volatile memory card, another ROM, etc., as long as the program code can be stored, or a download via a network. Can be used.
[0065]
When the computer executes the readout program code, not only the functions of the above-described embodiment are realized, but also an OS (Operating System) or the like running on the computer based on the instruction of the program code. Performs part or all of the actual processing, and the functions of the above-described embodiments are realized by the processing.
[0066]
Further, after the program code read from the storage medium is written into a memory provided in a function expansion board inserted into the computer or a function expansion unit connected to the computer, the function expansion is performed based on the instruction of the program code. It goes without saying that a CPU or the like provided in the board or the function expansion unit performs part or all of the actual processing, and the processing realizes the functions of the above-described embodiments.
[0067]
Although various examples and embodiments of the present invention have been described above, those skilled in the art will appreciate that the spirit and scope of the present invention are not limited to the specific description and drawings in this specification, and are not limited thereto. It goes without saying that it is possible to cover various modifications and changes all set forth in the claims.
[0068]
Examples of embodiments of the present invention are listed below.
[Embodiment 1] A document pressing plate for pressing a document placed on a document table,
A light source for irradiating the document with light,
Reflected light reading means for reading reflected light of light emitted to the document from the light source,
Open state detecting means for detecting the open state of the document pressure plate in at least two stages,
Document size detection wherein predetermined control corresponding to the open state of the document pressure plate detected by the open state detection means is performed, and the size of the document is determined based on the result of reading by the reflected light reading means. apparatus.
[0069]
[Embodiment 2] A document pressure plate for pressing a document placed on a document table,
A light source for irradiating the original with light,
Reflected light reading means for reading the reflected light of the light applied to the document from the light source, and an open state detecting means for detecting the open state of the document pressure plate in at least two stages,
When the open state detecting means detects that the original pressure plate is in the open state of the first stage, the power of the light source and the reflected light reading means is turned on, and the original state of the original pressure plate is detected by the open state detection means. When it is detected that the document is in the second stage open state, which is an opening degree lower than the first stage open state, the size of the document is determined based on the output result of the reflected light reading unit. Characteristic document size detection device.
[0070]
[Embodiment 3] The power supply of the light source and the reflected light reading means is turned off when the document pressing plate is in an opening degree higher than the opening state of the first stage. Document size detection device as described.
[0071]
[Embodiment 4] It has a sub-scanning direction detecting means for detecting the size of a document in the sub-scanning direction,
4. The document size detecting apparatus according to claim 2, wherein the size of the document is determined based on an output result of the sub-scanning direction detecting means and an output result of the reflected light reading means.
[0072]
[Embodiment 5] A reflected light reading step of reading reflected light of light emitted from a light source on a document placed on a document table and pressed by a document pressure plate,
An open state detecting step of detecting an open state of the document pressure plate in at least two stages,
Document size detection wherein predetermined control corresponding to the open state of the document pressure plate detected by the open state detection step is performed, and the size of the document is determined based on the reading result of the reflected light reading step. Method.
[0073]
[Embodiment 6] A reflected light reading step of reading reflected light of light emitted from a light source onto a document placed on a document table and pressed by a document pressure plate,
An open state detecting step of detecting an open state of the document pressure plate in at least two stages,
When it is detected by the open state detection step that the original platen is in the first stage open state, the light source and the power of the reflected light reading step are turned on, and the original state platen is detected by the open state detection step. When it is detected that the document is in the open state of the second stage, which is an open state lower than the open state of the first stage, the size of the document is determined based on the output result in the reflected light reading step. Characteristic document size detection method.
[0074]
[Embodiment 7] The power supply of the light source and the reflected light reading step is turned off when the document pressing plate is in an opening degree higher than the opening state of the first stage. Document size detection method described.
[0075]
[Eighth Embodiment] A sub-scanning direction detecting step of detecting a size of a document in the sub-scanning direction is provided,
8. The document size detecting method according to claim 6, wherein the size of the document is determined based on an output result of the sub-scanning direction detecting step and an output result of the reflected light reading step.
[0076]
[Embodiment 9] A control program comprising program code for causing a computer to execute each step of the document size detection method according to any one of Embodiments 6 to 8.
[0077]
[Embodiment 10] A storage medium storing the control program according to Embodiment 9.
[0078]
【The invention's effect】
As described above, according to the document size detection device of the present invention, it is possible to perform document size detection in a state where disturbance light is unlikely to enter and at an optimal opening angle of the document pressure plate, thereby preventing erroneous detection due to disturbance light. It is possible to accurately detect the document size while reducing the size.
[0079]
Further, according to the document size detection device of the present invention, it is possible to accurately detect the document size while reducing erroneous detection due to disturbance light, and realize the detection of a document size resistant to disturbance light. In order to save energy and extend the life of the document size detection device, it is possible to return from the state where the power supply of the document size detection sensor or the like is normally turned off at the time of document size detection and detect the document size.
[Brief description of the drawings]
FIG. 1 is a schematic front view showing a configuration of an image reading apparatus to which a document size detecting device according to a first embodiment of the present invention is applied.
FIG. 2 is a schematic side view illustrating a configuration of an image reading system in the image reading apparatus to which the document size detecting device according to the first embodiment of the present invention is applied.
FIG. 3 is a plan view showing a configuration of a document placing table in the image reading apparatus to which the document size detecting device according to the first embodiment of the present invention is applied.
FIG. 4 is a block diagram illustrating a configuration of an image reading apparatus to which the document size detecting device according to the first embodiment of the present invention is applied.
FIG. 5 is a plan view showing detection points used for determining the size of a document on a document placing table in an image reading apparatus to which the document size detecting device according to the first embodiment of the present invention is applied.
FIG. 6 is an explanatory diagram of document size detection when a fluorescent lamp is provided above the image reading device in the image reading device to which the document size detecting device according to the first embodiment of the present invention is applied;
FIG. 7 is a flowchart showing a flow of a detection operation according to a conventional document size detection method.
FIG. 8 is a diagram illustrating an example of a reading result by a conventional document size detection method.
FIG. 9 is a diagram for explaining a problem in the conventional document size detection method.
FIG. 10 is an explanatory diagram in a case where the opening angle of a document pressure plate is reduced in a conventional document size detection method.
FIG. 11 is a diagram for explaining a problem when the opening angle of a document pressure plate is reduced in a conventional document size detection method.
FIG. 12 is a flowchart illustrating a flow of an operation of the document size detecting device according to the first embodiment of the present invention.
FIG. 13 is a diagram illustrating an example of a reading result in the document size detection device according to the first embodiment of the present invention.
FIG. 14 is a diagram illustrating an example of a determination result of a main scanning length direction size and a determination result of a document size detection sensor in the conventional document size detection method and the document size detection method according to the first embodiment of the present invention. is there.
FIG. 15 is an explanatory diagram in a case where the document size detection device according to the first embodiment of the present invention detects the document with the opening angle of the document pressure plate set to 15 °.
FIG. 16 is a schematic side view illustrating a configuration of an image reading system in a document size detecting device according to a second embodiment of the present invention.
FIG. 17 is a flowchart illustrating an operation flow of the document size detecting device according to the second embodiment of the present invention.
[Description of sign]
101 manuscript
102 Document Placement Table
103 light source
104 First mirror
105 First optical bench
106 second mirror
107 Third mirror
108 Second optical bench
109 lens
110 CCD (Charge Coupled Device)
111 Document Size Detection Sensor
112 Original platen
113 Optical sensor
114 Optical Sensor
115 Sensor flag
116 housing
301 Original Size Label
302 Document alignment mark
401 A / D conversion circuit
402 Optical motor
403 Scanner controller
404 display
601 Fluorescent lamp (external light source)
1601 Optical sensor

Claims (1)

A document pressure plate for pressing a document placed on the document table,
A light source for irradiating the document with light,
Reflected light reading means for reading reflected light of light emitted to the document from the light source,
Open state detecting means for detecting the open state of the document pressure plate in at least two stages,
Document size detection wherein predetermined control corresponding to the open state of the document pressure plate detected by the open state detection means is performed, and the size of the document is determined based on the result of reading by the reflected light reading means. apparatus.

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