JP6204035B2 - Document size detection device, image reading device, and document size detection method - Google Patents

Description

  The present invention relates to a document size detection device, an image reading device, and a document size detection method, and relates to a document size detection device, an image reading device, and a document size detection device that can detect the size of a document in the main scanning direction without being affected by ambient light. The present invention relates to a document size detection method.

  As an image reading apparatus mounted on a digital multifunction peripheral or the like, a book scanner system is known in which a carriage provided with reading means is scanned to read a document on a platen glass. In this image reading apparatus, when a document is scanned by the book scanner method, a user sets the document on the platen glass. At this time, usually, the size of the set document is automatically detected. For example, when a document is copied by a user's operation, the image reading apparatus notifies the user by an alarm or the like if the sheet size of the document detected automatically is not in the sheet cassette.

  A document size detection apparatus that automatically detects the size of a document is disclosed in Patent Document 1. FIG. 8 shows a document size detection apparatus disclosed in Patent Document 1. In FIG. In the document size detecting apparatus shown in FIG. 8, the document mat is closed after the document is placed on the document placing table by the operation of the user. At this time, one line of the document placed on the document placement table is read by the image sensor with the light source turned off after the document mat opening / closing switch is turned on and before the document mat is completely closed. Thereafter, one line of the document placed on the document placement table is read by the image sensor with the light source turned on. In the image data read with the light source turned off, disturbance light is read as white pixels as shown in FIG. Further, as shown in FIG. 9B, the image data read with the light source turned on is read as a black pixel when the document is not present, and as a mixture of white and black pixels as the document portion. . Also, the disturbance light portion is read as white pixels. Then, the document size detection apparatus subtracts the image data read with the light source turned off from the image data read with the light source turned on, as shown in FIG. The image data from which is removed is acquired. Based on the image data, the edge of the document in the main scanning direction is determined. Furthermore, the approximate position of the edge of the document on the side of the sub-scanning direction is determined based on detection signals from the first reflection type sensor and the second reflection type sensor. The size of the document is detected based on the determined edge of the document in the main scanning direction and the approximate position of the edge of the document on the sub-scanning direction side.

JP 2000-138798 A

  The document size detection device disclosed in Patent Document 1 described above reads a document with the light source turned on and the light source turned off until the document mat is completely closed. Then, the image data read with the light source turned off is subtracted from the image data read with the light source turned on to obtain image data from which the influence of disturbance light has been removed. Based on the image data, the edge of the document in the main scanning direction is determined. However, in the image data from which the influence of disturbance light is removed (FIG. 9C), the edge of the document is obtained because the edge of the document is white or light as shown in FIG. 9C. Only if it is a color. For this reason, the document size detection device disclosed in Patent Document 1 has a document edge detection method in which the edge of the document is dark (when the background color of the document is dark, the document has a dark frame, etc.) Since the edge in the main scanning direction cannot be obtained, there is a problem that the size of the document in the main scanning direction cannot be detected.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a document size detecting device, an image reading device, and a document size detecting method capable of detecting the size of a document in the main scanning direction without being affected by disturbance light by solving the above problems. That is.

The document size detection apparatus of the present invention includes a glass for setting a document to be read, a cover that covers the glass in a closed state and a white cover on the side that covers the glass, and turns off the document reading lamp with the cover open. Read the set original in the main scanning direction to obtain a first reading result, and with the cover open, turn on the original reading lamp and read the original in the main scanning direction. An image reading unit that obtains a third reading result by turning on the original reading lamp and reading the original in the main scanning direction with the cover closed. Subtracting the second read result from the read result and adding the first read result to the result, the value of the calculated data changes below a predetermined value based on the position of the calculated data in the main scanning direction. Oh Position is detected and has and a document size detection section for detecting a main scanning direction size of the document on the basis of the edge position,
An image reading apparatus according to the present invention includes the document size detecting device according to the present invention and a printing unit, and the image reading unit of the document size detecting apparatus includes a carriage including a reading unit, and scans the carriage. Then, the original on the glass is read, and the read data is output, and the printing unit prints the read data on the paper of the original size detected by the original size detecting device.

  The document size detection method of the present invention covers a glass having a rectangular surface for setting a document when the document is read in a closed state, a white cover on the side covering the glass is opened, and a document reading lamp is opened. Read the original set on the glass in the main scanning direction, get the first reading result, and with the cover open, turn on the original reading lamp and read the original in the main scanning direction The second reading result is acquired, and with the cover closed, the original reading lamp is turned on, the original is read in the main scanning direction, the third reading result is acquired, and the third reading result is acquired. The second reading result is subtracted from the result, and the value of the calculation data obtained by adding the first reading result to the result is changed to a predetermined value or less, based on the position of the calculation data in the main scanning direction. Position Out, to detect the main scanning direction size of the document on the basis of the edge position, and so.

  According to the present invention, it is possible to provide a document size detection device, an image reading device, and a document size detection method that can detect the size of a document in the main scanning direction without being affected by disturbance light.

It is a figure which shows an example of the original document size detection apparatus which concerns on the 1st Embodiment of this invention. It is a figure which shows an example of the 1st reading result read with the original document size detection apparatus which concerns on the 1st Embodiment of this invention. It is a figure which shows an example of the 2nd reading result read with the original document size detection apparatus which concerns on the 1st Embodiment of this invention. It is a figure which shows an example of the 3rd reading result read with the original document size detection apparatus which concerns on the 1st Embodiment of this invention. It is a figure which shows an example of the 1st difference data calculated with the original document size detection apparatus which concerns on the 1st Embodiment of this invention. It is a figure which shows an example of the 2nd difference data calculated with the original document size detection apparatus which concerns on the 1st Embodiment of this invention. It is a figure which shows an example of the original document size detection apparatus which concerns on the 2nd Embodiment of this invention. It is a figure which shows an example of the 1st difference data calculated with the original document size detection apparatus which concerns on the 2nd Embodiment of this invention. It is a figure which shows an example of the 2nd difference data calculated with the original document size detection apparatus which concerns on the 2nd Embodiment of this invention. It is a figure which shows an example of the table for determining the fixed size of a document. It is a figure which shows an example of a state when each original of each size shown in FIG. 6 is abutted against the abutting position of the original size detecting apparatus according to the second embodiment of the present invention. It is a figure which shows the original document size detection apparatus in related technology. It is a figure which shows the read image data of the document in related technology.

Next, embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
FIG. 1 is a diagram showing an example of a document size detection apparatus according to the first embodiment of the present invention.

  FIG. 1A is a perspective view of the document size detection device 1, and FIG. 1B is a side view of the document size detection device 1.

  The document size detection apparatus 1 according to the present embodiment includes a glass 4, a cover 5, an image reading unit 2, and a document size detection unit 3. FIG. 1 also shows a lamp (original reading lamp) that is turned on when reading an original and a white plate that is set to make the inside of the cover 5 white.

  The glass 4 is a platen glass having a square surface, for example, and sets a document to be read.

  The cover 5 is a platen cover, is connected to the housing so as to be openable and closable, covers the glass 4 in a closed state, and has a white plate on the side (inner side) covering the glass 4. FIG. 1 shows the open state.

With the cover 5 opened, the image reading unit 2 turns off the lamp, reads, for example, one line of the document set at the document setting position on the glass 4 surface in the main scanning direction, and acquires the first reading result. .
When the image reading unit 2 reads a document, the document is set to a document setting position where the document is abutted against the back butting position and the left butting position. Further, with the cover 5 opened, the lamp is turned on to read one line of the original in the main scanning direction, for example, and obtain a second reading result. Then, with the cover 5 closed, the lamp is turned on to read, for example, one line of the document in the main scanning direction, and obtain a third reading result.

  The document size detection unit 3 subtracts the first reading result from the second reading result to obtain first difference data. Then, the first difference data is subtracted from the third reading result to obtain second difference data. That is, the document size detection unit 3 subtracts the second reading result from the third reading result and adds the first reading result to the result as the second difference data. Then, the edge position of the document is detected based on the position of the second difference data in the main scanning direction where the value of the second difference data changes to a predetermined value or less, and the main scanning direction of the document is determined based on the edge position. Detect the size of. Here, the first reading result, the second reading result, the third reading result, the first difference data, and the second difference data are all image data for one line at a predetermined scanning start position. (For example, 8,000), for example, stored in a storage unit (not shown) in order in the main scanning direction.

  Next, the operation of the document size detection apparatus according to the present embodiment will be described with reference to FIGS. 2A, 2B, 2C, 3A, and 3B.

  FIG. 2A is a diagram illustrating an example of a first reading result. The vertical axis represents the gradation of the data (brightness: for example, a value from 0 to 255). For example, 0 is true black and 255 is true white. The middle between 0 and 255 is gray. The horizontal axis represents the position of one line data from the near side of the glass 4 to the rear end position. This figure shows image data read for one line at the scanning start position with the lamp turned off with the cover 5 opened. The white light data shows the area affected by ambient light. The data of the original part is black data because the lamp is turned off.

  FIG. 2B is a diagram illustrating an example of a second reading result. Similar to FIG. 2A, the vertical axis represents the gradation (brightness) of the data, and the horizontal axis represents the position of one line data. This figure shows image data read by turning on the lamp with the cover 5 opened. However, an example is shown in which the first reading result shown in FIG. 2A is read with the cover 5 slightly closed compared to when the first reading result is read. Since the cover 5 is slightly closed compared to when the first reading result is read, the influence of ambient light is slightly reduced, and the white data portion is entirely smaller than the white data portion shown in FIG. 2A. Yes. The data of the portion without the document is black data. In the data of the original portion, since the lamp is lit, white data and black data are mixed. Here, an example of a document in which the color of the edge portion on the near side is dark is shown.

  FIG. 2C is a diagram illustrating an example of a third reading result. Similar to FIG. 2A, the vertical axis represents the gradation (brightness) of the data, and the horizontal axis represents the position of one line data. This figure shows image data read by turning on the lamp with the cover 5 closed, and the data of the original portion contains both white data and black data because the lamp is lit. Further, since the cover 5 is closed, the data of the white plate portion that is not hidden by the document is white data, and there is no portion affected by disturbance light.

  FIG. 3A is a diagram illustrating an example of first difference data. The vertical axis represents data corresponding to the gradation (brightness) of the data, and the horizontal axis represents the position of one line data. Since the first difference data is data obtained by subtracting the first reading result from the second reading result, the data of the original portion remains as it is, and the portion affected by the disturbance light is negative data.

  FIG. 3B is a diagram illustrating an example of second difference data. The vertical axis represents data corresponding to the gradation (brightness) of the data, and the horizontal axis represents the position of one line data. Since the second difference data is data obtained by subtracting the first difference data from the third reading result, the data of the original portion is lost. Then, the data of the white plate portion that is not hidden by the original is the data in which the portion affected by the disturbance light remaining as negative data in the first difference data is put. Therefore, the edge of the data of the white plate portion that is not hidden by the document becomes the edge position of the document.

  Here, the document is set to the document setting position on the glass 4 by the user, and the image reading unit 2 detects a user's predetermined operation (for example, pressing a switch indicating start, moving the cover 5 in the closing direction, etc.). To do. For example, a user's predetermined operation is detected based on a start switch (not shown) or a sensor (not shown) that detects an operation of the cover 5 in the closing direction. Then, with the cover 5 opened, the lamp is turned off and the original is read, for example, one line in the main scanning direction, and the first reading result shown in FIG. 2A is acquired. Next, the image reading unit 2 reads the original, for example, one line in the main scanning direction by turning on the lamp in a state where the cover 5 is open (for example, a state in which the cover 5 is closed more than in the first reading result). The second reading result shown in FIG. Then, the image reading unit 2 detects that the cover 5 is completely closed, for example, by a cover closing sensor (not shown), turns on the lamp, reads one line in the main scanning direction, for example, and reads the document in FIG. 2C. A third reading result is obtained.

  Next, the document size detector 3 subtracts the first reading result from the second reading result to obtain the first difference data shown in FIG. 3A. Then, the first difference data is subtracted from the third reading result to obtain the second difference data shown in FIG. 3B. The second difference data is only data of the white plate portion that is not hidden by the original. Therefore, the edge of the data of the white plate portion that is not hidden by the document becomes the edge position of the document. Then, the document size detection unit 3 detects a position in one line in the main scanning direction where the value of the second difference data changes to a predetermined value or less (position where the color falls from white to black in FIG. 3B). The edge position of the document. Here, the predetermined value is a value close to the brightness of true black, for example, “5”, and may be appropriately changed for each apparatus without being particular about this value. Then, the document size detection unit 3 detects the size of the document in the main scanning direction from the edge position of the document and a predetermined depth abutting position.

As described above, according to the first embodiment of the present invention, the document size detection unit obtains the second difference data of only the white plate portion data that is not hidden by the original document, and the white plate portion data is obtained from this data. The position of the edge, that is, the position of the edge of the document is detected. For this reason, even if the color of the edge portion of the document is dark, the size of the document in the main scanning direction can be detected without being affected by ambient light.
(Second Embodiment)
FIG. 4 is a diagram showing an example of a document size detection apparatus according to the second embodiment of the present invention.

  4A is a perspective view of the document size detection apparatus 1, and FIG. 4B is a side view of the document size detection apparatus 1. FIG.

  In the second embodiment of the present invention, a plurality of sub-scanning direction size sensors for detecting the size of the document in the sub-scanning direction are further provided in the first embodiment. In addition, the document size detection unit 3 and the image reading unit 2 of the document size detection device 1 according to the first embodiment are more specific. Therefore, the difference from the first embodiment will be mainly described.

  The document size detection apparatus 1 according to the present embodiment includes a glass 4, a cover 5, an image reading unit 2, a document size detection unit 3, and a plurality of sub-scanning direction size sensors (sub-scanning direction size sensor A7, sub-scanning size sensor A7). And a scanning direction size sensor B8).

  FIG. 4 shows a lamp (document reading lamp) that is turned on when reading a document, an angle sensor 6 that detects the closing angle of the cover 5, a cover closing sensor that detects that the cover 5 is completely closed, and a glass 4. A carriage that scans the top and reads pixel data of the document is also described.

  The sub-scanning direction size sensor A7 and the sub-scanning direction size sensor B8 are set along the sub-scanning direction in the vicinity of the rear abutting position of the glass 4 for setting the document, and these sub-scanning direction size sensors are turned on and off. Based on this, the size of the document in the sub-scanning direction is detected.

The document size detection unit 3 subtracts the first reading result shown in FIG. 2A from the second reading result shown in FIG. 2B to obtain a positive portion as first difference data, and the third reading shown in FIG. 2C. The first difference data is subtracted from the result to obtain second difference data. Then, the difference between the value of the data of interest in the second difference data and the value of the data around the data of interest, for example, the average of 10 data is sequentially taken in the main scanning direction. Then, the edge position of the document is detected based on the position of the data of interest in the main scanning direction when this difference is equal to or less than a predetermined threshold value.
The document size detection unit 3 determines the document size based on the size of the document in the main scanning direction and the size of the document in the sub scanning direction detected by the plurality of sub scanning direction size sensors. The size of the original in the main scanning direction is obtained from the edge position of the original and the back-abutting position that is the end of the original setting position on the glass 4 surface on which the original to be read is set.

  The image reading unit 2 opens the cover 5 at a predetermined first angle from the surface of the glass 4 with the outer side of the main scanning direction end (back contact position) of the document setting position on the glass 4 as an axis. In the state, the first reading result is acquired. Further, the cover 5 is opened at a predetermined second angle from the surface of the glass 4 to obtain a second reading result. Here, the second angle is at least smaller than the first angle. The smaller the angle, the less the influence of ambient light.

  The angle sensor 6 is pressed by the cover 5 that moves in the closing direction, and detects the angle of the cover 5 according to the pressing distance, for example, a pair of a vertically long bar and a light shielding sensor. Then, for example, the angle of the cover 5 corresponding to the predetermined position is detected by blocking the light of the light shielding sensor provided at the predetermined position by the tip of the rod. The angle detected can be increased by increasing the number of light shielding sensors.

  Next, the operation of the document size detection apparatus according to the present embodiment will be described with reference to FIGS. 2A, 2B, 2C, 5A, 5B, 6, and 7. FIG.

  2A, 2B, and 2C are described in the first embodiment.

  FIG. 5A is a diagram illustrating an example of first difference data. The vertical axis represents data corresponding to the gradation (brightness) of the data, and the horizontal axis represents the position of one line data. The first difference data is data obtained by subtracting the first reading result shown in FIG. 2A from the second reading result shown in FIG. 2B. For this reason, the data of the original part remains as it is, and the part affected by the disturbance light is eliminated.

  FIG. 5B is a diagram illustrating an example of second difference data. The vertical axis represents data corresponding to the gradation (brightness) of the data, and the horizontal axis represents the position of one line data. Since the second difference data is data obtained by subtracting the first difference data shown in FIG. 5A from the third reading result shown in FIG. 2C, the data of the document portion is lost. Then, the data is only the data of the white plate portion that is not hidden by the original. Therefore, the edge of the data on the white plate portion is the edge position of the document.

FIG. 6 is a table for determining the standard size of a document. The standard size of the document is determined in correspondence with the detection result of the sub-scanning direction size sensor A7, the detection result of the sub-scanning direction size sensor B8, and the size of the document in the main scanning direction obtained by the document size detection unit 3.
The size ranges (D, E, F, G, H, J, K) in the main scanning direction in the table are associated as follows. That is, the detected size X (unit: mm) in the main scanning direction is D when 144 <X <= 163, E when 163 <X <= 195, F when 195 <X <= 213, and 213 <X. <= 226, G Further, it is assumed that H is 226 <X <= 262, I is 262 <X <= 275, J is 275 <X <= 289, and K is 289 <X <= 301. The sub-scanning direction size sensor A7 and the sub-scanning direction size sensor B8 are “1” when the detection result is ON, and “0” when the detection result is OFF. On the other hand, the standard document sizes A3, A4, A5, B4, and B5 indicate the sizes of A3, A4, A5, B4, and B5, and the Letter indicates the letter size. S indicates that the length of the document in the main scanning direction is shorter than the length in the sub-scanning direction. L indicates that the length of the document in the main scanning direction is longer than the length in the sub-scanning direction.

  FIG. 7 shows a position where the original of each size shown in FIG. 6 is abutted against the back of the original setting position on the glass 4 surface, which is the end in the main scanning direction, and the left abutting is the end in the sub-scanning direction. The state when it hits against the position is shown. When the document is read by the image reading unit 2, the document is set to the document setting position that is in contact with the back butting position and the left butting position.

  Here, in a state where the cover 5 is opened, the document is set to the document setting position on the glass 4 by the user, and the cover 5 is rotated in the closing direction by the user operation. At this time, the lamp is turned off, and the carriage has moved to the scanning start position.

  When the image reading unit 2 detects that the cover 5 has reached the first angle based on the angle sensor 6, the image reading unit 2 reads, for example, one line in the main scanning direction, and the first reading result shown in FIG. 2A. To get.

  Next, when the image reading unit 2 turns on the lamp and detects that the cover 5 is at the second angle based on the angle sensor 6, the image reading unit 2 reads, for example, one line in the main scanning direction. The second reading result shown in 2B is acquired. When the cover 5 reaches the second angle, for example, the cover 5 is in a more closed state than at the first angle.

  When the image reading unit 2 detects that the cover 5 is completely closed by the cover closing sensor, the image reading unit 2 reads, for example, one line in the main scanning direction with the lamp turned on, and the first reading shown in FIG. 2C. Acquire three reading results.

  Next, the document size detection unit 3 subtracts the first reading result from the second reading result to obtain a positive portion and obtains first difference data shown in FIG. 5A. Then, the first difference data is subtracted from the third reading result to obtain the second difference data shown in FIG. 5B. The edge of the data of the white plate portion that is not hidden by the document is the edge position of the document.

  Then, the document size detection unit 3 determines the value (tone value) of the target data (target data pixel) and the value of the data (data pixel) around the target data (target data pixel) in the second difference data. The difference between (gradation value) and, for example, the average of 10 data is sequentially taken in the main scanning direction. Here, the average of 10 data is used, but the value may be appropriately changed for each apparatus without being particular about this value. Then, when this difference is equal to or less than a predetermined threshold value (gray lightness, for example, “128”. The value may be appropriately changed for each apparatus without being particular about this value). The edge position of the document is detected based on the position. Then, the document size detection unit 3 detects the size of the document in the main scanning direction from the edge position of the document and a predetermined depth abutting position.

  Next, the document size detection unit 3 acquires detection results of the sub-scanning direction size sensor A7 and the sub-scanning direction size sensor B8. Based on the detection result and the detected size of the original in the main scanning direction, the standard size of the original set on the glass 4 is determined using the table of FIG.

  As described above, according to the second embodiment of the present invention, the document size detection unit obtains the second difference data of only the white plate portion data that is not hidden by the original document, and the white plate portion data is obtained from this data. The position of the edge, that is, the position of the edge of the document is detected. For this reason, even if the color of the edge portion of the document is dark, the size of the document in the main scanning direction can be detected without being affected by ambient light. Further, the standard size of the document set on the glass 4 can be determined based on the detected size of the document in the main scanning direction and the detection result of the sensor that detects the size of the document in the sub-scanning direction.

  The document size detection apparatus 1 described above is used in, for example, an image reading apparatus mounted on a digital multifunction peripheral or the like. The image reading apparatus includes a document size detection device 1, a printing unit (not shown), and a communication unit (not shown), for example. This image reading apparatus scans a carriage provided with reading means such as a reading element that receives reflected light of lamp light from the original and outputs pixel data, and reads the original on the glass 4. Then, the read result is printed by, for example, a printing unit (not shown) on a sheet having a size detected by the document size detection device 1. Also, data in a range corresponding to the size of the document detected by the document size detection device 1 among the read data is transferred to a host device such as an information processing device connected via a communication unit (not shown).

Part or all of the above-described embodiments can be described as in the following supplementary notes, but is not limited thereto.
(Appendix 1)
A glass for setting the original to be scanned,
Covering the glass in a closed state and covering the glass with a white cover;
With the cover open, the original reading lamp is turned off to read the set original in the main scanning direction to obtain a first reading result. With the cover open, the original reading lamp Is turned on to read the original in the main scanning direction to obtain a second reading result, and with the cover closed, the original reading lamp is turned on to read the original in the main scanning direction. An image reading unit for acquiring the reading result of
Subtracting the second read result from the third read result and adding the first read result to the result, the value of the calculated data changes below a predetermined value based on the position of the calculated data in the main scanning direction. A document size detection unit that detects an edge position of the document and detects a size of the document in the main scanning direction based on the edge position;
An apparatus for detecting a document size.
(Appendix 2)
The document size detection unit subtracts the first reading result from the second reading result to obtain a positive portion to obtain first difference data, and the first difference data is obtained from the third reading result. The difference between the value of the data of interest in the subtracted second difference data and the average of the values of the data around the data of interest is sequentially taken in the main scanning direction, and when this difference falls below a predetermined threshold Detecting an edge position of the document based on a position of the attention data;
The document size detecting apparatus according to appendix 1, wherein:
(Appendix 3)
The image reading unit has a predetermined first angle with respect to the glass surface opened from the glass surface having a square surface about the outside of the end portion in the main scanning direction of the position where the document is set. The first reading result is obtained in the open state, and the cover is moved to the second in the open state at a predetermined second angle that is at least smaller than the first angle from the glass surface. Get the reading result,
The document size detection apparatus according to Supplementary Note 2, wherein
(Appendix 4)
The document size detection unit detects the size of the document in the main scanning direction based on the detected edge position and the document setting position on the glass surface on which the document to be read is set.
The document size detecting device according to appendix 2 or 3, characterized by the above.
(Appendix 5)
A plurality of sub-scanning direction size sensors that are set along the sub-scanning direction of the glass for setting the original and detect the size of the original in the sub-scanning direction;
The document size detection unit determines the document size based on the detected size of the document in the main scanning direction and the size of the document in the sub scanning direction detected by the plurality of sub scanning direction size sensors.
The document size detecting device according to appendix 2, 3 or 4, characterized by the above.
(Appendix 6)
The document size detection device according to appendix 5,
A printing section, and
The image reading unit of the document size detecting device has a carriage having a reading unit, scans the carriage to read a document on glass, outputs the read data, and the printing unit reads the document. Printing the read data on paper of the document size detected by the size detection device;
An image reading apparatus.
(Appendix 7)
A communication unit that is connected to an information processing device and that transfers the read data in a range according to the document size detected by the document size detection device of the read data to the information processing device;
The image reading apparatus according to appendix 6, wherein:
(Appendix 8)
Cover the glass with a rectangular surface to set the document when reading the document in the closed state, the white cover on the side covering the glass, open the document reading lamp and turn the document reading lamp off, the document set on the glass Is read in the main scanning direction to obtain the first reading result,
With the cover open, the original reading lamp is turned on to read the original in the main scanning direction to obtain a second reading result,
With the cover closed, the original reading lamp is turned on to read the original in the main scanning direction to obtain a third reading result,
Subtract the second reading result from the third reading result,
The edge position of the original is detected based on the position of the calculation data in the main scanning direction where the value of the calculation data obtained by adding the first reading result to the result changes to a predetermined value or less,
Detecting the size of the document in the main scanning direction based on the edge position;
An original size detection method characterized by the above.
(Appendix 9)
Subtracting the first reading result from the second reading result to obtain a positive part as the first difference data,
The difference between the value of the data of interest in the second difference data obtained by subtracting the first difference data from the third reading result and the average of the values of the data around the data of interest are sequentially applied in the main scanning direction. And detecting the edge position of the document based on the position of the data of interest when the difference is equal to or less than a predetermined threshold.
The document size detection method as set forth in appendix 8, wherein:
(Appendix 10)
The cover is opened in a predetermined first angle from the glass surface opened with the outside of the main scanning direction end of the glass surface having a square surface set in the main scanning direction as an axis. Get the first reading result,
Obtaining the second reading result of the cover in an open state at a predetermined second angle that is at least smaller than the first angle from the glass surface;
The document size detection method according to appendix 9, wherein:
(Appendix 11)
Detecting the size of the original in the main scanning direction based on the detected edge position and the original setting position of the glass surface on which the original to be read is set;
11. The document size detection method according to appendix 9 or 10, wherein
(Appendix 12)
Detecting the size of the original in the sub-scanning direction;
Determining the document size based on the detected size of the document in the main scanning direction and the detected size of the document in the sub-scanning direction;
12. The document size detection method according to appendix 9, 10 or 11, wherein

DESCRIPTION OF SYMBOLS 1 Original size detection apparatus 2 Image reading part 3 Original size detection part 4 Glass 5 Cover 6 Angle sensor 7 Sub scanning direction size sensor A
8 Sub-scanning direction size sensor B

Claims (8)

A glass for setting the original to be scanned,
Covering the glass in a closed state and covering the glass with a white cover;
With the cover open, the original reading lamp is turned off to read the set original in the main scanning direction to obtain a first reading result. With the cover open, the original reading lamp Is turned on to read the original in the main scanning direction to obtain a second reading result, and with the cover closed, the original reading lamp is turned on to read the original in the main scanning direction. An image reading unit for acquiring the reading result of
The first reading result, the second reading result, and, on the basis of the third read result to detect an edge position of the document, detecting the main scanning direction size of the document on the basis of the edge position A document size detection unit to be
With
The document size detection unit subtracts the first reading result from the second reading result to obtain a positive portion to obtain first difference data, and the first difference data is obtained from the third reading result. The difference between the value of the data of interest in the subtracted second difference data and the average of the values of the data around the data of interest is sequentially taken in the main scanning direction, and when this difference falls below a predetermined threshold detecting the edge position based on the position of the target data,
A document size detecting apparatus characterized by the above. The image reading unit is an end portion of the glass having a square surface, and the cover is located on the outside of the end portion in the main scanning direction at the document setting position where the document is set. The first reading result is acquired in an open state opened at a predetermined first angle, and the cover is at least smaller than the first angle with respect to the glass with the outside as an axis. Obtaining the second reading result in an open state opened at a second angle;
2. The document size detecting apparatus according to claim 1, wherein The document size detection unit detects the size of the document in the main scanning direction based on the detected edge position and the document setting position of the glass for setting a document to be read.
3. The document size detection apparatus according to claim 1, wherein the document size detection apparatus is a document size detection apparatus. A plurality of sub-scanning direction size sensors that are set along the sub-scanning direction of the glass for setting the original and detect the size of the original in the sub-scanning direction;
The document size detection unit determines a standard size of the document based on the detected size of the document in the main scanning direction and the size of the document in the sub scanning direction detected by the plurality of sub scanning direction size sensors. To
4. The document size detecting apparatus according to claim 1, 2, or 3. A document size detecting device according to claim 4,
A printing section, and
The image reading unit of the document size detection apparatus includes a carriage having a reading unit, scans the carriage to read the document on the glass, outputs the read data, and the printing unit Printing the read data on the standard size paper detected by the document size detection device;
An image reading apparatus. A communication unit that is connected to an information processing device and that transfers the read data in a range according to the standard size detected by the document size detection device of the read data to the information processing device;
The image reading apparatus according to claim 5. Cover the glass with a rectangular surface to set the document when reading the document in the closed state, the white cover on the side covering the glass, open the document reading lamp and turn the document reading lamp off, the document set on the glass Is read in the main scanning direction to obtain the first reading result,
With the cover open, the original reading lamp is turned on to read the original in the main scanning direction to obtain a second reading result,
With the cover closed, the original reading lamp is turned on to read the original in the main scanning direction to obtain a third reading result,
Subtracting the first reading result from the second reading result to obtain a positive part as the first difference data,
The difference between the value of the data of interest in the second difference data obtained by subtracting the first difference data from the third reading result and the average of the values of the data around the data of interest are sequentially applied in the main scanning direction. And detecting the edge position of the document based on the position of the data of interest when the difference is equal to or less than a predetermined threshold,
Detecting the main scanning direction size of the document on the basis of the edge position,
An original size detection method characterized by the above. An end portion of the glass having a square surface, the cover having a predetermined first relative to the glass with respect to the outside of the end portion in the main scanning direction at the document setting position, which is a position for setting the document. In the open state where the angle is opened, the first reading result is obtained,
The second reading result is acquired in an open state in which the cover is opened at a predetermined second angle that is at least smaller than the first angle with respect to the glass with the outer side as an axis.
The document size detecting method according to claim 7.

Images