JP2009181504A - Electronic writing tool and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electronic writing tool and the like, capable of acquiring information from a code image such as a bar code by enabling image composition in reading of the code image. <P>SOLUTION: In a code image reading mode, generally, since a reading area (imaging area or cutting area) is set slightly wide (refer to (a)), or since reading is performed from a number of light receiving elements of an infrared CMOS 614, the frame rate is low. As a result, a point where reading of a bar code cannot be performed due to missing of a read image even if the reading is tried may be caused. In a bar code reading mode, the number of light receiving elements which perform reading of pixel signal is reduced as shown in (b) to improve the frame rate. That is, an area for performing the reading of pixel signal is reduced to improve the frame rate. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an electronic writing instrument and a program.

2. Description of the Related Art In recent years, attention has been paid to a technique in which characters, figures, and the like written on a medium such as paper are converted into electronic data, which is transferred to a personal computer, a mobile phone, etc., and the written contents are stored.
For example, Patent Document 1 describes the following technique. That is, when a medium on which fine dots formed with different patterns on the surface are printed and a pen device with an image sensor, for example, are written on the medium by the pen device, A dot pattern at the position of a character, a figure, or the like is read into the image sensor, and the position coordinates of the position of the character, the figure, etc. (drawing trace) are specified. Thereby, generation of an electronic document composed of written characters, graphics, etc., addition of characters, graphics, etc. to a predetermined electronic document are performed.

JP 2004-94907 A

By the way, when reading a code image such as a barcode using an electronic writing instrument such as a pen device equipped with an image sensor or the like, it is necessary to synthesize an image. However, in the case of the same imaging range and frame rate, depending on the scanning speed of the electronic writing instrument that moves on the barcode, the image may be missing or the common area is too small to produce an accurate composition even if there is no missing. Problems such as inability to occur may occur. In order to prevent this, it is necessary to secure a sufficient frame rate at the same time as expanding the imaging range, but in general, the imaging range and the frame rate are in a trade-off relationship that balances the processing capability of the image sensor, so it is not possible to increase both Have difficulty.
An object of the present invention is to provide an electronic writing instrument or the like that enables image composition when reading a code image such as a barcode, and enables acquisition of information from the code image.

According to the first aspect of the present invention, a plurality of light receiving elements are arranged in a two-dimensional matrix, and an image pickup unit that picks up an image on a medium and a light receiving element included in a predetermined region of the image pickup unit are used for the medium A first mode for capturing an image on the upper side, a second mode for capturing an image on the medium using a light receiving element included in an area smaller than the predetermined area of the imaging unit, and the first mode An electronic writing instrument having switching means for switching between a mode and the second mode.
According to the second aspect of the present invention, in the second mode, when a plurality of code images attached to the medium are captured in pieces, an image generation that generates a composite image that reproduces the entire code image The electronic writing instrument according to claim 1, further comprising means.
The invention according to claim 3 is the electronic writing instrument according to claim 2, further comprising information acquisition means for acquiring information relating to the code image from the composite image generated by the image generation means.
According to a fourth aspect of the present invention, there is provided grasping means for grasping a density distribution in an image picked up in the second mode based on a signal from each light receiving element included in the small region, and the grasping means 4. The electronic writing instrument according to claim 1, further comprising output means for outputting warning information when the grasped density distribution is not a predetermined distribution.
The invention according to claim 5 is the electronic writing instrument according to any one of claims 1 to 4, further comprising changing means for changing a position of the small area.
The invention according to claim 6 is characterized in that the changing means changes the position of the small area when the density distribution in the image picked up in the second mode is not a predetermined distribution. Item 5. The electronic writing instrument according to Item 5.
According to a seventh aspect of the present invention, when a code image indicating a position in the medium is captured from the medium in the first mode, position information acquisition means for acquiring position information from the code image is further provided. The switching means switches from the first mode to the second mode when the position information acquired by the position information acquisition means is predetermined position information. It is an electronic writing instrument in any one of thru | or 6.
According to the eighth aspect of the present invention, when a code image indicating a position in the medium is captured from the medium in the first mode, the trajectory information of the electronic writing instrument with respect to the medium is obtained based on the code image. Further comprising trajectory information acquisition means for acquiring, the switching means is determined that the electronic writing instrument is approaching a code image attached to the medium based on the trajectory information acquired by the trajectory information acquisition means. In this case, the electronic writing instrument according to claim 1, wherein the electronic writing instrument is switched from the first mode to the second mode.

The invention according to claim 9 is output from a light receiving element in a first area including an imaging unit having a plurality of light receiving elements and a plurality of light receiving elements among the plurality of light receiving elements in the imaging unit. A first reading mode for acquiring a signal, and a second reading mode for acquiring a signal output from a light receiving element in a second area including a plurality of light receiving elements smaller than the first area of the imaging unit. , An electronic writing instrument.
According to a tenth aspect of the present invention, a signal output from a light receiving element in a third area that is different from the second area and includes a plurality of light receiving elements smaller than the first area is acquired. The electronic writing instrument according to claim 9, further comprising a third mode.
The eleventh aspect of the present invention is the electronic writing instrument according to the tenth aspect, wherein the third area is formed so as to intersect the second area.
The invention according to claim 12 is the electronic writing instrument according to claim 10 or 11, wherein the third area is formed so as to be substantially orthogonal to the second area.
The invention according to claim 13 is included in a first function of reading a signal from a light receiving element included in a predetermined region of the imaging unit having a plurality of light receiving elements, and in a region smaller than the predetermined region of the imaging unit. And a second function for reading a signal from the light receiving element.

According to the first aspect of the present invention, it is possible to increase the frame rate by the second mode, and it is possible to reduce the state in which the code image is missing in the captured image.
According to claim 2 of the present invention, it is possible to grasp the entire code image even when a plurality of code images are captured in a fragmentary manner.
According to the third aspect of the present invention, for example, when the code image is a barcode, it is possible to acquire the barcode information.
According to the fourth aspect of the present invention, for example, it is possible to issue a warning to the user when the orientation of the electronic writing instrument is not suitable for obtaining barcode information or the like.
According to claim 5 of the present invention, it is possible to increase the possibility of acquiring bar code information and the like as compared with the case where the present invention is not adopted.
According to the sixth aspect of the present invention, even when the density distribution in the image captured in the second mode is not a predetermined distribution and is not suitable for acquiring the barcode information or the like, the barcode information or the like is acquired. It becomes possible.
According to the seventh aspect of the present invention, compared with the case where the present invention is not adopted, for example, the operation when the user reads the barcode can be simplified.
According to Claim 8 of this invention, compared with the case where this invention is not employ | adopted, operation when a user reads a barcode, for example can be simplified.

According to the ninth aspect of the present invention, it is possible to increase the frame rate by the second reading mode, and it is possible to reduce the state in which the code image is missing in the captured image.
According to the tenth aspect of the present invention, the possibility of acquiring, for example, bar code information can be further increased as compared with the case where the present invention is not adopted.
According to the eleventh aspect of the present invention, for example, even when the second area is in a state along the bar constituting the code and the barcode information or the like cannot be obtained, the code information can be obtained.
According to the twelfth aspect of the present invention, the possibility of obtaining bar code information or the like can be further increased.
According to the thirteenth aspect of the present invention, it is possible to provide a program capable of reducing a state in which a code image is missing in a captured image.

The best mode for carrying out the present invention (hereinafter referred to as “embodiment”) will be described below in detail with reference to the accompanying drawings.
First, the overall configuration of the handwriting information management system in the present embodiment will be described.
FIG. 1 is a diagram showing an example of the configuration of the handwriting information management system of the present embodiment. As shown in FIG. 1, the handwriting information management system includes a terminal device 10, a document server 20, an identification information server 30, an image forming device 40, and a terminal device 50 connected to a network 80. It is configured. A digital pen 60 is connected to the terminal device 50 via a communication device 70.

  In the handwriting information management system of this embodiment, when a print request for an electronic document is made from the terminal device 10, the document server 20 receives the print request from the terminal device 10, and the print request is sent to the image forming apparatus 40. An instruction to print the electronic document is issued. Thereby, the image forming apparatus 40 prints the document image of the electronic document on a medium such as paper. At this time, the image forming apparatus 40 prints a code image on the medium in addition to the document image.

The code image here is an image of the identification code and the position code obtained by encoding the identification information and the position information. The identification information is information for uniquely identifying a medium, and is issued by the identification information server 30 in the present embodiment. The position information is information for specifying the coordinate position on the medium, and is generated by the document server 20 in the present embodiment.
When the user writes with the digital pen 60 on the medium on which the document image and the code image are printed, the digital pen 60 generates handwritten information (handwriting information) based on the position information included in the code image. . At the same time, the digital pen 60 recognizes identification information included in the code image. Then, the recognized identification information and handwriting information are sent to the document server 20 via the terminal device 50. The document server 20 that has received the identification information and the handwriting information specifies the electronic document printed on the medium based on the identification information, and stores the specified electronic document and the handwriting information in association with each other.

In this specification, electronic data that is the basis of an image recorded on a medium is expressed as “electronic document”. However, this does not mean only data obtained by digitizing a “document” including text. For example, "electronic document" including image data (regardless of raster data or vector data) such as pictures, photographs, figures, etc., data recorded by database management software or spreadsheet software, and other printable electronic data It is said.
In the present specification, the “medium” may be any material as long as it can print an image. A typical example is paper, but it may be a plastic sheet such as an OHP sheet or a metal plate. Furthermore, in this specification, processing is performed using identification information for uniquely identifying each of the electronic document, the medium, and the digital pen 60 and the user. It shall mean the identification information. That is, in the present embodiment, this identification information is used as an example of medium identification information uniquely given to the medium.

Then, each component which comprises the handwriting information management system of this Embodiment is demonstrated in detail.
The terminal device 10 is a computer device that requests the document server 20 to print an electronic document. Here, as the terminal device 10, for example, a personal computer, a workstation, or another computer is used.
The document server 20 is a computer device that stores and manages electronic documents. Also, when a request for printing an electronic document is received from the terminal device 10, an image of the electronic document and a code image representing identification information and position information are generated, and a print command for printing a composite image obtained by synthesizing the image on a medium is generated. Output to the forming apparatus 40. Here, as the document server 20, for example, a personal computer, a workstation, or another computer is used.

The identification information server 30 is a computer device that issues identification information to be given to a medium. The issued identification information is stored in association with the electronic document printed on the medium to which the identification information is assigned. Here, as the identification information server 30, for example, a personal computer, a workstation, or another computer is used.
The image forming apparatus 40 is an apparatus that prints an image on a medium and outputs it as a print document. The image forming apparatus 40 may be a single printer or printing machine, or may be a so-called “multifunction machine” having a scanner or a communication function. Here, as an image forming method in the image forming apparatus 40, for example, an electrophotographic method may be used, but other methods may be used.

  The terminal device 50 transmits information obtained by digitizing writing on the print document (hereinafter referred to as “handwriting information”) to the identification information server 30 in order to reflect the information in the electronic document that is the basis of the image recorded in the print document. A computer device. Alternatively, the electronic document to be reflected in the handwriting information may be displayed on a display (not shown), and the handwriting information may be displayed on the display. Here, as the terminal device 50, for example, a personal computer, a workstation, or another computer is used. In the present embodiment, handwriting information is used as an example of handwriting information obtained by digitizing the contents of writing. The handwriting information is mainly described as handwritten information, but is not limited to this, and includes, for example, information mechanically drawn by a plotter that is a device for outputting drawing data such as architecture and machinery.

A digital pen 60 as an example of an electronic writing instrument is a pen device used for writing characters or figures on a printed document. An image sensor that reads a code image or a bar code printed on the medium is provided. Then, position information is detected from the code image read by the image sensor, and handwriting information obtained by converting written characters or figures into image data is generated and stored based on the position information. Also, barcode information is acquired from an image read from the image sensor and stored.
The communication device 70 is a device that acquires handwriting information and bar code information from the digital pen 60 and transmits them to the terminal device 50. Examples of a communication method between the communication device 70 and the digital pen 60 and a communication method between the communication device 70 and the terminal device 50 include USB (Universal Serial Bus), Bluetooth (registered trademark), an infrared communication function, and the like. Various schemes are used. In FIG. 1, the communication device 70 is shown as a separate body from the digital pen 60, but the communication device 70 is not necessarily a separate body and may be configured integrally.

Subsequently, details of each component constituting the handwriting information management system will be described.
First, the configuration of the document server 20 will be described.
FIG. 2 is a block diagram illustrating an example of a functional configuration of the document server 20. As shown in FIG. 2, the document server 20 includes a reception unit 21, an identification information acquisition unit 22, an electronic document management unit 23, a handwriting information management unit 24, and a document / handwriting information storage unit 25. Further, it includes an identification code generation unit 27a, a position code generation unit 27b, a code arrangement unit 27c, a pattern image storage unit 27d, and a code image generation unit 27e. Furthermore, a document image generation unit 26, an image composition unit 28, and a transmission unit 29 are provided.

The receiving unit 21 receives a print request from the terminal device 10. Here, in addition to the electronic document, the print request includes identification information (hereinafter referred to as “document ID”) of the electronic document to be printed and various kinds of information for determining the layout of the electronic document on the printed medium. Settings (hereinafter referred to as “print settings”) are included. The document ID is assigned to each electronic document by the terminal device 10, but may be assigned by the document server 20. Further, the receiving unit 21 receives from the identification information server 30 identification information that is uniquely given to the medium on which the print document is printed. Further, when writing is performed on the print document, the identification information embedded in the print document and handwriting information obtained by digitizing the content of the print document (written image) are received from the identification information server 30. .
The identification information acquisition unit 22 acquires the document ID and print settings from the reception unit 21, passes them to the transmission unit 29, instructs transmission of an identification information issue request, passes this to the document image generation unit 26, and sends the document Instructs generation of an image. Further, the identification information of the medium is acquired from the receiving unit 21, and this is passed to the identification code generating unit 27a to instruct generation of the identification code.

  The electronic document management unit 23 acquires the identification information and the electronic document received by the reception unit 21 and registers them in the document / handwriting information storage unit 25 in association with each other based on the document ID. Also, a new electronic document (second electronic document) that reflects the state of the electronic document stored in the document / handwriting information storage unit 25 printed on the medium according to the print settings is generated, and the generated second The second electronic document is stored in the document / handwriting information storage unit 25. Further, when the display or printing of the electronic document is instructed, the corresponding identification information and electronic document are taken out from the document / handwriting information storage unit 25.

The handwriting information management unit 24 acquires the identification information and handwriting information received by the receiving unit 21 and registers the handwriting information in the document / handwriting information storage unit 25 in association with the electronic document based on the identification information. When the display of handwriting information is instructed, the corresponding identification information and handwriting information are extracted from the document / handwriting information storage unit 25.
The document / handwriting information storage unit 25 stores an electronic document managed by the electronic document management unit 23 and handwriting information managed by the handwriting information management unit 24. Here, in the present embodiment, the document / handwriting information storage unit 25 is provided as an example of a storage unit that stores the identification information, the electronic document, and the handwriting information in association with each other.

The identification code generation unit 27a generates identification code by encoding identification information for specifying a medium.
The position code generation unit 27b encodes position information indicating the coordinate position on the medium to generate a position code.
The code arrangement unit 27c arranges the identification code generated by the identification code generation unit 27a, the position code generated by the position code generation unit 27b, and the like on a two-dimensional plane according to a predetermined layout (see FIG. 3 in the subsequent stage). Then, a two-dimensional code array is generated.
The pattern image storage unit 27d stores a pattern image corresponding to the code value of each code stored in the code array.
The code image generation unit 27e refers to the two-dimensional code array generated by the code arrangement unit 27c, selects a pattern image corresponding to each code value, and generates a code image.

The document image generation unit 26 acquires a document ID and print settings from the identification information acquisition unit 22, and reads an electronic document specified by the document ID from the document / handwriting information storage unit 25. Then, a document image of the electronic document is generated according to the print setting.
The image composition unit 28 synthesizes the code image generated by the code image generation unit 27e and the document image generated by the document image generation unit 26 to generate a composite image.
The transmission unit 29 transmits an identification information issuance request to the identification information server 30. Also, an image print command for the medium is transmitted to the image forming apparatus 40. Furthermore, when the display of handwriting information is instructed, the identification information and handwriting information are transmitted to the identification information server 30.

Here, the code image generated by the document server 20 of the present embodiment will be described.
FIG. 3 is a diagram illustrating an example of an image constituting the code image. First, unit patterns constituting a code image will be described. FIG. 3A shows an example of the unit pattern.
The unit pattern is the minimum unit for embedding information. In FIG. 3A, a black area and a shaded area are areas where dots can be arranged, and a white area between them is an area where dots cannot be arranged. In addition, among the areas where dots can be arranged, dots are arranged in black areas, and dots are not arranged in hatched areas. That is, FIG. 3A shows an example in which a unit pattern is configured by arranging dots at two places (black areas) selected from nine places where dots can be arranged. Here, since there are 36 (= ₉ C ₂ ) combinations for selecting 2 locations out of 9 locations, there are 36 types of unit patterns. Of these, four types of unit patterns are used as synchronization patterns. The synchronization pattern is a pattern for detecting the rotation of the image and specifying the relative positions of the identification code and the position code. In particular, since it is necessary to detect the rotation of the image, the four types of synchronization patterns are selected such that when one of the synchronization patterns is rotated 90 degrees, another synchronization pattern is obtained. Further, the 32 types of unit patterns other than the 4 types of unit patterns are used as information patterns expressing the identification code and the position code, and 5-bit information is expressed.

  By the way, the dots shown in FIG. 3A are only for information representation, and do not necessarily coincide with the dots that mean the minimum points constituting the image. In the present embodiment, dots for information expression (the minimum square in FIG. 3A) have a size of 2 dots × 2 dots at 600 dpi. Since the size of one dot at 600 dpi is 0.0423 mm, one side of a dot for information expression (the minimum square in FIG. 3A) is 84.6 μm (= 0.0423 mm × 2). The larger the dot for information expression, the more likely it is to be noticeable. Therefore, it is preferable that the dot is as small as possible. However, if it is too small, printing with a printer becomes impossible. Therefore, the above values larger than 50 μm and smaller than 100 μm are employed as the size of dots for information expression. However, the above value 84.6 μm is a numerical value to the last, and is about 100 μm in the actually printed toner image. In the present specification, the term “dot” refers to a dot for information expression, not a dot that means the minimum point constituting an image unless otherwise specified.

Next, a code block composed of such unit patterns will be described. FIG. 3B shows an example of the layout of the code block. Here, not the image but the code arrangement immediately before being replaced by the pattern image is shown. That is, a unit pattern as shown in FIG. 3A (any one of 36 unit patterns) is arranged in the smallest square (hereinafter referred to as “unit block”) in FIG. Will be formed.
In the layout of FIG. 3B, the synchronization code is arranged in one unit block at the upper left of the code block. Further, the X position code is arranged in the four unit blocks on the right side of the unit block in which the synchronization code is arranged, and the Y position code is arranged in the four unit blocks on the lower side of the unit block in which the synchronization code is arranged. . Furthermore, identification codes are arranged in 16 (= 4 × 4) unit blocks surrounded by unit blocks in which these position codes are arranged.

Here, encoding of identification information will be described.
When encoding identification information, the bit string which comprises identification information is divided | segmented into a some block in order to perform RS encoding. Although there are several methods for encoding, RS encoding is suitable in this embodiment. This is because the RS code is a multi-value coding method, and in this case, the value represented by the unit block corresponds to the multi-value of the RS code. For example, when 5-bit information is expressed by one unit block, the 60-bit identification information is divided into 12 blocks having a block length of 5 bits. If an RS code capable of correcting two blocks of errors is employed, the code length is 16 blocks, which can be accommodated in a unit block in which the identification code in the code block of FIG. Note that the encoding method is not limited to the RS code, and other encoding methods such as a BCH code may be used.

Subsequently, encoding of position information will be described.
For encoding the position information, an M-sequence code, which is a kind of pseudo-random sequence, is used. Here, the M sequence refers to a sequence having the longest period among a shift register having a certain length and a code sequence generated by feedback. When K is the number of stages in the shift register, the sequence length of the M sequence is 2 ^K −1. Arbitrary consecutive K bits extracted from the M sequence have a property that they do not appear at other positions in the same M sequence. Therefore, the position information is encoded using this property.
By the way, in the present embodiment, a necessary M-sequence order is obtained from the length of position information to be encoded, and an M-sequence is generated. However, if the length of the position information to be encoded is known in advance, it is not necessary to generate the M sequence each time. That is, a fixed M sequence may be generated in advance and stored in a memory or the like.
For example, it is assumed that an M sequence (K = 13) having a sequence length of 8191 is used. In this case, since the position code is also embedded in units of 5 bits, 5 bits are taken out from the M sequence having a sequence length of 8191 and blocked.

  In this specification, the identification information and the position information are clearly distinguished and used for the sake of simplicity. However, there is a technique in which a wide range of position information is prepared, the position information is cut out and embedded from different ranges for each medium, and the medium is identified by the difference in position information. Therefore, in such a method, it is assumed that the position information has a function for identifying the medium, and the position information is also considered as the identification information.

Next, the configuration of the identification information server 30 will be described.
FIG. 4 is a block diagram illustrating an example of a functional configuration of the identification information server 30. As illustrated in FIG. 4, the identification information server 30 includes a reception unit 31, an identification information management unit 32, an identification information storage unit 33, a display information generation unit 34, and a transmission unit 39.
The receiving unit 31 receives an identification information issue request from the document server 20. The receiving unit 31 receives medium identification information and handwriting information from the terminal device 50 when writing is performed on the print document. Here, in the present embodiment, the medium identification information and the handwriting information are received from the terminal device 50, and when the display of the handwriting information is instructed, the medium identification information and the handwriting information are obtained from the document server 20. A receiving unit 31 is provided as an example of receiving means for receiving.

When there is a request for issuing identification information, the identification information management unit 32 issues the identification information without duplication, and stores the document ID and print settings specified at that time in association with the identification information. In response to designation of identification information, a document ID and print settings corresponding to the identification information are extracted.
The identification information storage unit 33 stores the identification information in the used / unused state, the document ID of the electronic document printed on the medium to which the identification information is added, and the electronic document printed on the medium to which the identification information is printed. It is a database that stores print settings in association with each other.
The display information generation unit 34 generates display information for displaying the handwriting information based on the information acquired from the document server 20 when the display of the handwriting information is instructed. As this display information, for example, data serving as a source for generating an image to be displayed on the terminal device 50 is generated.
The transmission unit 39 transmits identification information issued in response to a request from the document server 20 to the document server 20. In addition, when writing on a print document is performed, medium identification information and handwriting information are transmitted to the document server 20. Further, when the display of handwriting information is instructed, the display information is transmitted to the terminal device 50.

Next, the digital pen 60 will be described.
FIG. 5 is a diagram illustrating the functional configuration of the digital pen 60. As shown in the figure, the digital pen 60 includes a control circuit 611 that controls the operation of the entire pen. The control circuit 611 includes a first image processing unit 611a that processes the read code image, and a second image processing unit 611b that processes the read image and acquires barcode information.
The control circuit 611 is connected to a writing pressure detection switch 612 that detects a writing operation by the digital pen 60 by pressure (writing pressure) applied to the pen tip 619 and sets the digital pen 60 to an operating state. Further, an infrared LED 613 that irradiates the medium with infrared light and an infrared CMOS (Complementary Metal Oxide Semiconductor) 614 that reads a code image or the like by detecting reflected light are also connected.

  Furthermore, the control circuit 611 includes an information memory 615 for storing identification information, position information, barcode information, etc., a communication circuit 616 for communicating with an external device, and a battery 617 for driving a pen. A pen ID memory 618 for storing pen identification information (pen ID) is connected. Further, a detection switch 621 provided so as to be interlocked with an operation button 620 exposed to the outside of the digital pen 60 and a display LED 622 for displaying predetermined information to the outside are connected. Note that the display LED 622 may be arranged in the operation button 620 so that the operation button 620 and the information display function are combined. The infrared CMOS 614 is connected to the control circuit 611 via a horizontal scanning circuit and a vertical scanning circuit (both not shown) for driving the infrared CMOS 614 so as to select a light receiving element (pixel) for reading out a signal. Is done. The infrared CMOS 614 has a plurality of light receiving elements such as photodiodes arranged in a two-dimensional matrix, and functions as an imaging unit that captures an image on a medium.

A functional configuration realized in the control circuit 611 will be described in detail. FIG. 6 is a block diagram illustrating an example of a functional configuration of the control circuit 611.
As described above, the control circuit 611 includes the first image processing unit 611a and the second image processing unit 611b. The control circuit 611 includes an image acquisition unit 630, a mode change unit 631, a CMOS control unit 632, a display control unit 633, and a transmission unit 634.

The first image processing unit 611a has a function of processing the code image read as described above. Here, the first image processing unit 611a includes a dot array generation unit 641, a code array generation unit 642, an identification information acquisition unit 643, a position information acquisition unit 644, and a handwriting information generation unit 645.
The dot array generation unit 641 generates a dot array with reference to the dot positions in the code image. That is, on a two-dimensional array, for example, “1” is stored at a position where there is a dot and “0” is stored at a position where there is no dot, thereby replacing the dot detected as an image with digital data. Then, this two-dimensional array is output as a dot array.

  The code array generation unit 642 detects a block corresponding to the unit pattern in the code block on the dot array. Specifically, a frame having the same shape and size as the block in which the unit pattern is arranged is moved on the dot array, and the frame is fixed at a position where the number of dots in the frame becomes equal. For example, if the unit pattern of FIG. 3A is used, a frame having a size corresponding to 3 dots × 3 dots is moved, and the frame is fixed at a position where the number of dots included in the frame is 2. Then, a code array is generated that stores code values determined from dot positions in each block delimited by the frame. When this code array is generated, the position of the synchronization code is specified by searching for a code value of a predetermined synchronization code.

The identification information acquisition unit 643 detects the identification code based on the position of the synchronization code from the code array. Then, the identification code is decoded using the parameters used in the RS encoding process at the time of image generation, and identification information is acquired.
The position information acquisition unit 644 detects a position code based on the position of the synchronization code from the code array. Then, an M-sequence partial sequence is extracted from the position code, the position of this partial sequence in the M-sequence used at the time of image generation is referenced, and a value obtained by correcting this position with an offset using a synchronization code is acquired as position information. The reason for correcting with the offset is that a synchronization code is arranged between the position codes.

  The handwriting information generation unit 645 generates handwriting information by connecting the position information acquired by the position information acquisition unit 644. Here, the handwriting information includes at least data obtained by digitizing the locus of the pen tip of the digital pen 60, but may include other information. Information other than the locus of the pen tip includes, for example, information on the color set for the pen when writing, information on writing pressure, and the like.

On the other hand, the second image processing unit 611b processes the image read as described above to obtain barcode information. Here, the second image processing unit 611b includes an image composition unit 651, an intersection detection unit 652, and a code information acquisition unit 653.
The image synthesis unit 651 generates a synthesized image by synthesizing a plurality of sequentially input image data. An intersection detection unit 652 that also functions as a grasping unit grasps the density distribution of the input image data and detects an intersection where the density distribution intersects with a predetermined density threshold. The number of intersection points is acquired and output. The code information acquisition unit 653 detects (recognizes) a barcode from input image data, acquires the barcode information, and outputs the acquired barcode information.

The image acquisition unit 630 acquires an image read by the infrared CMOS 614 from a medium (print document). Further, noise included in the image is removed as necessary.
The mode change unit 631 reads a barcode from a print document (hereinafter referred to as “barcode reading mode”) from a mode (hereinafter referred to as “code image reading mode”) that reads a code image from a printed document (medium). ) Or change the mode from the barcode reading mode to the code image reading mode.
The CMOS control unit 632 controls the operation of the infrared CMOS 614 through the horizontal scanning circuit and the vertical scanning circuit. Specifically, the CMOS control unit 632 selects a light receiving element on the infrared CMOS 614 that reads out a pixel signal through the horizontal scanning circuit and the vertical scanning circuit, and outputs a pixel signal from the selected light receiving element. Infrared CMOS 614 is controlled as described above. Further, the CMOS control unit 632 sets a frame rate when the infrared CMOS 614 captures an image.
The display control unit 633 controls the operation of the display LED 622. For example, the display color of the display LED 622 is changed according to the reading mode.
The transmission unit 634 implements information transmission to the communication device 70 by passing the identification information acquired by the identification information acquisition unit 643 and the handwriting information generated by the handwriting information generation unit 645 to the communication circuit 616. In addition, the transmission unit 634 realizes information communication to the communication device 70 by passing the barcode information acquired by the code information acquisition unit 653 to the communication circuit 616.

  FIG. 7 conceptually shows an operation until acquisition of handwriting information (writing data) in the code image reading mode. In the digital pen 60, first, the infrared LED 613 irradiates the medium with infrared light, and the infrared CMOS 614 receives the reflected light to read the code image. Then, the image acquisition unit 630 acquires the read code image. At that time, if noise is included in the code image, it is removed. Next, decoding is performed. Specifically, the dot array generation unit 641 converts the dot positions included in the code image into digital data and generates a dot array. Then, the code array generation unit 642 detects a block from the dot array and generates a code array that stores a code value for each block. Then, the position of the synchronization code is specified in the code array. Thereafter, the identification information acquisition unit 643 detects the identification code based on the position of the synchronization code, decodes it, and acquires identification information (indicated as a document ID in the figure). In addition, the position information acquisition unit 644 detects a position code based on the position of the synchronization code, decodes this, and acquires position information. Then, the handwriting information generation unit 645 generates handwriting information (writing data) by connecting the position information. Then, the transmission unit 634 transmits these pieces of information to the identification information server 30 via the communication device 70 and the terminal device 50. The operation when acquiring barcode information will be described later.

FIG. 8 is a diagram illustrating a hardware configuration of the control unit 611 of the digital pen 60.
As shown in the figure, the control unit 611 is a functional module that performs digital arithmetic processing according to a predetermined operation control program (firmware) when performing operation control of the digital pen 60, and processing executed by the CPU 101. RAM 102 in which programs are stored, ROM 103 in which data such as setting values used in processing programs executed by CPU 101 are stored, EEROM and flash memory that are rewritable and can retain data even when power supply is interrupted A non-volatile memory 104 such as a memory, and an interface unit 105 that controls input / output of signals to / from each unit connected to the control unit 611 are provided.
The external storage device 106 stores an operation control program to be executed by the control unit 611. When the control unit 611 reads this processing program, the operation control related to the digital pen 60 is executed.

  That is, the operation for realizing the functions of the first image processing unit 611a, the second image processing unit 611b, the image acquisition unit 630, the mode change unit 631, the CMOS control unit 632, the display control unit 633, and the transmission unit 634 described above. The control program is read from the external storage device 106 into the RAM 102 in the control unit 611. The CPU 101 performs various processes based on the operation control program read into the RAM 102. In this operation control program, for example, a hard disk or a DVD-ROM provided in the terminal device 50 that communicates with the digital pen 60 functions as the external storage device 106 of the digital pen 60, and the RAM 102 is connected from the terminal device 50 via the communication line. Provided to be loaded into. As another providing form, there is a form provided in a state installed in the ROM 103 in advance. Furthermore, after the digital pen 60 is assembled, an operation control program is installed in the nonvolatile memory 104 and loaded from the nonvolatile memory 104 to the RAM 102. Further, there is a form in which a program is transmitted to the digital pen 60 via a network such as the Internet and installed in the RAM 102.

Next, various processes performed on the electronic document in the handwriting information management system of the present embodiment will be described.
[Print document generation processing]
FIG. 9 is a sequence diagram illustrating an example of an operation when a print document is generated in the handwriting information management system.
First, the user transmits an instruction to print an electronic document from the terminal device 10 to the document server 20 (step 101). At that time, the terminal device 10 transmits an electronic document to be printed, identification information (document ID) of the electronic document, and print settings designated by the user. Here, the print settings include the page to be printed, the number of copies, the size of the paper that is the medium, the enlargement / reduction ratio, N-up (printing that allocates N pages of the electronic document to one page of the medium), and the size of the margin area. Including settings such as.

The document server 20 receives an electronic document print instruction from the terminal device 10 (step 201). The electronic document to be printed included in the print instruction is sent to the electronic document management unit 23, and the electronic document management unit 23 registers the electronic document in the document / handwriting information storage unit 25 in association with the document ID (step 202). ).
Further, the document server 20 transmits the document ID and print setting of the electronic document instructed to be printed to the identification information server 30 (step 203). Here, for example, a URL (Uniform Resource Locator) may be used as the document ID, but other information may be used as long as the electronic document can be uniquely identified.
Thereby, the identification information server 30 receives the document ID and the print setting (step 301). Then, the identification information management unit 32 that manages the medium identification information acquires unused medium identification information from the identification information storage unit 33 (step 302). Here, the number of pieces of medium identification information to be extracted is determined according to print settings. That is, basically, the number of pieces of medium identification information obtained by multiplying the number of pages to be printed by the number of copies is extracted. However, if N-up printing is specified in the print setting information, this is also taken into consideration. For example, when printing 5 copies of a 10-page electronic document by 2-up printing, 25 (= 10 ÷ 2 × 5) pieces of medium identification information are extracted.
Next, the identification information server 30 associates the identification information, the document ID, and the print settings and registers them in the identification information storage unit 33 (step 303). Then, the identification information server 30 transmits the identification information to the document server 20 (step 304).

Thereby, the document server 20 receives the identification information (step 204). Then, a code image representing the identification information and the position information is generated (step 205).
That is, in the document server 20, the receiving unit 21 receives the medium identification information. Then, the reception unit 21 passes the received medium identification information to the identification information acquisition unit 22. Then, the identification information acquisition unit 22 first passes the acquired medium identification information to the identification code generation unit 27a, and the identification code generation unit 27a encodes the medium identification information using the method described above to generate an identification code. .
In addition, the position code generation unit 27b receives print settings from the reception unit 21, encodes position information in a range corresponding to the print settings using the above-described method, and generates a position code.
Then, the code arrangement unit 27c arranges the medium identification code and the position code according to a predetermined layout, and the code image generation unit 27e converts the image into an image using the pattern image stored in the pattern image storage unit 27d. A code image is generated by.

Thereafter, in the document server 20, the document image generation unit 26 generates a document image of the electronic document (step 206). At that time, the document image generation unit 26 receives the document ID acquired by the identification information acquisition unit 22 in step 201, and reads an electronic document to be printed from the document / handwriting information storage unit 25 based on the document ID. In step 201, the print setting acquired by the identification information acquisition unit 22 is received, and a document image is generated based on the print setting.
Then, the image composition unit 28 synthesizes the code image generated in step 205 and the document image generated in step 206 to generate a composite image (step 207).
Thereafter, the composite image is transferred to the transmission unit 29, and the transmission unit 29 transmits a print command for the composite image to the image forming apparatus 40 (step 208). Here, the composite image print command is transmitted, for example, in a PDL format in which the content to be printed as a code image is set as a PDL command to a PDL (Page Description Language) file including a sequence of print commands for document images. .

  The image forming apparatus 40 receives the composite image (document image and code image of the electronic document) from the document server 20 (step 401). Then, the image forming apparatus 40 develops the document image into an image using Y (yellow), M (magenta), and C (cyan) (step 402). Next, the document image is formed using C, M, and Y toners, and the code image is formed using K (black including carbon) toner (step 403).

In the above-described example, the identification information server 30 simply issues the identification information, and the document server 20 generates a code image including the identification information and instructs the image forming apparatus 40 to form an image. However, the identification information server 30 may generate a code image and instruct the image forming apparatus 40 to form an image.
Further, a configuration in which the code image is generated by the image forming apparatus 40 may be adopted. In that case, the document server 20 or the identification information server 30 adds the identification information to the PDL generated from the electronic document and transmits it to the image forming apparatus 40, and the image forming apparatus 40 generates a code image including the identification information. It will be.

  In the above example, the configuration in which the database (identification information storage unit 33) configured by associating the identification information, the document ID, and the print setting is placed in the identification information server 30 has been described. This is because placing such a database on a sharable device (identification information server 30) makes it possible to handle multiple users and ensure the security of electronic documents using server access control technology. However, such a configuration is not necessarily employed, and a configuration in which the above database is placed in the terminal device 10 or the document server 20 may be employed.

In the image forming apparatus 40 described above, the code image is formed using K (black containing carbon) toner. This is because the K toner has a larger amount of infrared light absorption than the C (cyan), M (magenta), and Y (yellow) toner, and the digital pen 60 can easily read the code image. is there. However, the code image can also be formed using special toner.
Here, as the special toner, an invisible toner having a maximum absorption rate of 7% or less in the visible light region (400 nm to 700 nm) and an absorption rate of 30% or more in the near infrared region (800 nm to 1000 nm) is exemplified. . Here, “visible” and “invisible” are not related to whether they can be recognized visually. “Visible” and “invisible” are distinguished depending on whether or not an image in a printed document can be recognized by the presence or absence of color development due to absorption of a specific wavelength in the visible light region. Also, “invisible” includes those that have some color developability due to absorption of a specific wavelength in the visible light region but are difficult to be recognized by human eyes.

  Here, the code image is combined with the image of the electronic document and printed. However, the code image may be printed on white paper (notebook, tag, etc.). In that case, the document ID is not included in the print request received in step 201, the identification information is not associated with the document ID and the print setting in step 303, and the generation of the document image in step 206 is not executed. What should I do?

[Handwriting information registration process]
Next, an operation when the digital pen 60 generates handwriting information and registers it in the document server 20 will be described.
As described above, in the digital pen 60, the identification information acquisition unit 643 acquires the identification information. Further, the position information acquisition unit 644 acquires position information. Further, the handwriting information generation unit 645 generates handwriting information by connecting the position information to each other. Then, the transmission unit 634 transmits identification information and handwriting information to the identification information server 30 via the communication device 70 and the terminal device 50. The identification information server 30 registers the handwriting information in the document server 20.

FIG. 10 is a sequence diagram illustrating an example of operations of the identification information server 30 and the document server 20 when registering handwriting information.
In the identification information server 30, first, the receiving unit 31 receives identification information and handwriting information from the digital pen 60 (step 311). Next, the identification information and handwriting information are passed to the identification information management unit 32, and the identification information management unit 32 takes out the document ID associated with the passed identification information from the identification information storage unit 33. Then, the document server 20 (the document server 20 in which the electronic document specified by the document ID exists) is determined as the transmission destination of the identification information and handwriting information received in step 311 (step 312). If the document ID is not associated with the identification information in the identification information storage unit 33, it is considered that the identification information is assigned to a blank sheet (note or tag). In that case, the document server 20 that manages the handwriting information for the white paper may be determined as the transmission destination.
Thereafter, the identification information and the handwriting information are transferred to the transmission unit 39, and the transmission unit 39 transmits the identification information and the handwriting information to the document server 20 determined as the transmission destination in Step 312 (Step 313).

  Thereby, in the document server 20, the receiving part 21 receives identification information and handwriting information (step 211). Then, the reception unit 21 passes the received identification information to the handwriting information management unit 24. Then, the handwriting information management unit 24 stores the identification information and the handwriting information in association with each other in the document / handwriting information storage unit 25 (step 212).

By the way, in the handwriting information management system of the present embodiment, the document server 20 manages electronic documents and handwriting information, and the identification information server 30 generates / manages identification information for uniquely identifying a medium. . However, various variations can be considered as to which apparatus performs these processes. For example, the process of generating / managing identification information may be performed by the document server 20, or may be performed by the terminal device 50 or the image forming apparatus 40. Further, the code image may be generated by the image forming apparatus 40.
Therefore, these processes can be generalized as being performed by the computer 90 as a general-purpose device. Accordingly, the hardware configuration of the computer 90 will be described on the assumption that the terminal device 10, the document server 20, the identification information server 30, the image forming device 40, and the terminal device 50 that constitute the handwriting information management system are configured by the computer 90. deep.

FIG. 11 is a diagram illustrating a hardware configuration of the computer 90.
As shown in FIG. 11, the computer 90 includes a CPU (Central Processing Unit) 91 that is a calculation means, a main memory 92 that is a storage means, and a magnetic disk device (HDD: Hard Disk Drive) 93. Here, the CPU 91 executes various software such as an OS (Operating System) and an application, and realizes each function described above. The main memory 92 is a storage area for storing various software and data used for execution thereof, and the magnetic disk device 93 is a storage area for storing input data for various software, output data from various software, and the like. .
Further, the computer 90 includes a communication I / F 94 for performing communication with the outside, a display mechanism 95 including a video memory and a display, and an input device 96 such as a keyboard and a mouse.
The program for realizing the present embodiment can be provided not only by communication means but also by storing it in a recording medium such as a CD-ROM.

By the way, the digital pen 60 in the present embodiment is configured to be able to acquire information on a barcode attached to a medium. Here, FIGS. 12 and 13 conceptually show the imaging area of the digital pen 60 in the present embodiment.
By the way, in the code image reading mode (first mode), the reading area (imaging area, cutout area) is generally set wider (see FIG. 13A), in other words, the infrared CMOS 614 Since reading from a large number of light receiving elements is performed, the frame rate is low. As a result, as shown in FIGS. 12A and 12B, even if the barcode is read, a portion of the read image is missing and cannot be read. As a result, it is difficult to appropriately obtain barcode information.

  Therefore, in the barcode reading mode (second mode) in this embodiment, as shown in FIG. 13B, the number of light receiving elements that read pixel signals is reduced, and the frame rate is improved. In other words, the area for reading out pixel signals is made small, and the frame rate is improved. More specifically, the total imaging pixel count is reduced and the frame rate is increased by widening the imaging range in the scanning direction but narrowing in the vertical direction with respect to scanning. Here, when the reading area in the code image reading mode is regarded as the first area, the reading area in the barcode reading mode may be regarded as a second area composed of a plurality of light receiving elements smaller than the first area. it can.

  Note that the barcode in the present embodiment is formed of K (black containing carbon) toner, that is, formed of toner having a predetermined infrared absorption amount, and image acquisition by the infrared CMOS 614 is possible. . The barcode shown in the present embodiment is a so-called one-dimensional barcode, and a plurality of predetermined bars are arranged in the longitudinal direction. Here, the one-dimensional barcode generally includes a thin bar having a width of about 0.3 mm and a thick bar having a width of about 1 mm, and these bars are arranged at predetermined small intervals. ing. On the other hand, the area length that can be imaged in the readout area (second area) is 5 to 10 mm in the present embodiment. In addition, even if the digital pen 60 is arranged to be inclined with respect to the medium, it is possible to capture about five bars. For this reason, image composition described later can be performed.

Here, FIG. 14 shows basic processing in the barcode reading mode.
First, the mode change unit 631 (an example of a switching unit) that has detected that the operation button 620 is pressed by the user and the detection switch 621 is turned on switches modes to the image acquisition unit 630, the CMOS control unit 632, and the display control unit 633. A predetermined signal for switching is output. Thereby, the display control part 633 performs display switching (step 501). For example, the display control unit 633 changes the lighting color of the display LED 622 lit in blue to red. Further, the CMOS control unit 632 sets (changes) the pixel signal readout area and frame rate (step 502).

  Specifically, the CMOS control unit 632 reduces the pixel signal readout area more than the readout area in the code image reading mode. In other words, the CMOS control unit 632 sets the pixel signal readout area in the horizontal direction so that the readout range in the vertical direction is extremely small at the center of the imageable area, as shown in FIG. A range is formed from one end to the other end of the imageable area. That is, it is a linear readout area along the horizontal direction. Further, the CMOS control unit 632 sets a frame rate larger than the frame rate in the code image reading mode.

  Next, when the writing operation is performed so as to trace on the barcode and the writing pressure detection switch 612 is turned on, infrared light is emitted from the infrared LED 613 and reflected light is received by the infrared CMOS 614 and an image is displayed. Read. As a result, the image acquisition unit 630 acquires an image read by the infrared CMOS 614 (step 503). Then, the acquired image is output to an image composition unit 651 that functions as an image generation unit, and the image composition unit 651 combines a plurality of images (fragment images) sequentially acquired by the image acquisition unit 630 ( Step 504), generating a composite image in which the entire barcode is reproduced.

Here, in the present embodiment, the pixel signal readout area is reduced as described above, and the readout area is narrower than the readout area in the code image readout mode. For this reason, a frame rate larger than the frame rate in the code image reading mode can be set as described above. As a result, the same portion of the barcode can be captured in a plurality of images. Thereby, the image composition unit 651 can perform image composition based on the same location in each image, and generate a composite image in which the entire barcode is reproduced.
Next, the code information acquisition unit 653 functioning as an information acquisition unit recognizes a barcode from the image synthesized by the image synthesis unit 651 (step 505), and acquires barcode information from the recognized barcode (step 505). 506). Thereafter, the transmission unit 634 transmits this barcode information to the terminal device 50 via, for example, the communication device 70 (step 507), and the process is terminated.

Here, FIG. 15 shows a read image or the like when the digital pen 60 rotates in the circumferential direction.
When the barcode is read, the digital pen 60 is normally moved along the arrangement direction of the barcode, but depending on the gripping state of the user, the digital pen 60 moves in a slightly rotated state in the circumferential direction. There is a case. As a result, as shown in FIG. 5B, the reading area may be along a bar (line) constituting the barcode. In such a case, it is difficult to fit the same portion of the barcode in a plurality of images, and image synthesis is difficult. Therefore, the density distribution (graph) is grasped based on the output signal output from each light receiving element (each pixel), and the number of intersections between the density distribution and a predetermined density threshold is grasped, and the number of intersections is less than the predetermined number. In this case, for example, a warning display can be performed. For example, a warning can be displayed when the number of intersections is one as shown in FIG. On the other hand, when the number of intersections is five as shown in FIG. 5A, image composition is possible and no warning is displayed.

Furthermore, when the number of intersections is less than a predetermined number, the readout area can be changed.
Here, FIG. 16 is a diagram for explaining the change of the readout area. As shown in FIG. 6A and as described above, when the reading area is arranged along the bar constituting the barcode and there is one intersection with the density threshold, it is difficult to synthesize the image. Therefore, in such a case, the readout area can be changed to a state rotated by 90 ° as shown in FIG. When the readout area is arranged in this way, the number of intersections with the density threshold increases as shown in FIG. 5B, that is, the longitudinal direction of the readout area and the longitudinal direction of the bar code are substantially aligned. Image synthesis is possible. Note that the number of intersections with the density threshold needs to be at least 2 or more, and is preferably 5 or more in view of certainty. Here, in the present embodiment, the state after the readout area is rotated by 90 ° can be regarded as the third mode. Further, the readout area in the third mode can be regarded as the third readout area with respect to the first readout area and the second readout area. This third readout area is arranged in a relationship (substantially orthogonal relationship) intersecting the second area.

Here, FIG. 17 is a flowchart showing processing executed by the control unit 611. The above process will be described in detail using this flowchart.
In this process, first, as described above, the display control unit 633 executes display switching (step 601). Next, the CMOS control unit 632 sets (changes) the pixel signal readout area and frame rate (step 602).

  Next, when the writing operation is performed so as to trace on the barcode and the writing pressure detection switch 612 is turned on, infrared light is emitted from the infrared LED 613 and reflected light is received by the infrared CMOS 614 and an image is displayed. Read. Thereby, the image acquisition part 630 acquires the image read by the infrared CMOS 614 (step 603). The intersection detection unit 652 that also functions as a grasping unit grasps the density distribution in the predetermined image acquired by the image acquisition unit 630, detects the intersection between the density distribution and the predetermined density threshold, Get the score. Thereafter, it is determined whether or not the number of intersections is a predetermined number or more (step 604). From another point of view, the intersection detection unit 652 grasps the concentration distribution and grasps the number of locations having a predetermined concentration value in the concentration distribution. And it is judged whether this number is more than predetermined number. If it is determined that the number of intersections is greater than or equal to the predetermined number, the image composition unit 651 generates a composite image obtained by combining the plurality of images acquired in step 603 as in step 504 (step 605). ). Thereafter, similarly to Steps 505 to 507, barcode recognition processing, barcode information acquisition processing, and transmission processing are executed (Steps 606 to 608), and the processing ends.

  On the other hand, when the intersection detection unit 652 that also functions as an output unit determines in step 604 that the intersection with the density threshold is less than a predetermined number (the number of locations having a predetermined density value is less than the predetermined number). Warning information is output to the display control unit 633. Accordingly, the display control unit 633 blinks the display LED 622 that is lit in red, for example, and displays a warning to the user (step 609). In this case, it can be changed to another color such as orange. Thereafter, the CMOS control unit 632 functioning as a changing unit changes the position of the readout area as shown in FIG. 16B (step 610).

  When the barcode is read again by the user and the image acquisition unit 630 acquires the read image (step 611), as in step 604, the intersection detection unit 652 determines whether the number of intersections is a predetermined number or more. It is determined whether or not (step 612). If the number is greater than or equal to the predetermined number, the processing of step 605 to step 608 is executed, that is, image synthesis, barcode recognition, barcode information acquisition, and barcode information transmission are executed, and the processing ends. To do. On the other hand, if it is determined in step 612 that the number of intersections is less than the predetermined number, the display control unit 633 issues a warning again (step 613), and the process ends. If the barcode cannot be read even in the second reading, it is assumed that the barcode itself is not formed in a state having a sufficient density change. For this reason, when performing the second warning display, the display control unit 633 can perform a warning display corresponding to the fact that there is no barcode having a sufficient density change. Further, for example, the information can be transmitted to the terminal device 50, and the terminal device 50 can display a warning that there is no barcode having a sufficient density change.

In the above description, the mode is switched based on the operation on the operation button 620. However, the mode can also be switched based on the reading of the code image attached to the medium.
Here, the mode change based on the reading of the code image attached to the medium can be performed when the code image at a predetermined position on the medium is read. In other words, an area for writing on the medium (writing area) and an area for instructing mode change (instruction area) are provided, and the location on the medium that the digital pen 60 contacts is any of these. The mode can be switched (changed) based on whether or not. Specifically, management information in which coordinate information of an area on the medium is associated with information indicating whether the area is a writing area or an instruction area is created. When the digital pen 60 touches the medium, the coordinate information is read, and the management information is referred to determine whether the area corresponding to the coordinate information is a writing area or an instruction area. Thereby, when the area corresponding to the coordinate information is an instruction area, the code image reading mode can be changed to the barcode reading mode.

Here, FIG. 18 shows the medium and the digital pen 60.
For example, the management information can be generated by associating the area A and the area B in the figure with information indicating the instruction area. Thereby, for example, when the position information in the region A is acquired, the code image reading mode can be changed to the barcode reading mode. Here, the acquisition of the position information is performed by the position information acquisition unit 644 functioning as a position information acquisition unit. The mode change unit 631 that functions as a switching unit changes the mode when it is determined that the position information acquired by the position information acquisition unit 644 is predetermined position information. Specifically, the mode is changed when the position information acquired by the position information acquisition unit 644 is associated with information indicating that it is an instruction area. When the barcode is read, as shown in the area A and the area B, generally, the digital pen 60 is first brought into contact with an area outside the barcode in the longitudinal direction (side of the barcode). For this reason, it is preferable to arrange | position the instruction | indication area | region in the outer side in the longitudinal direction of a barcode.

  Furthermore, management information about the position coordinates in the area where the barcode is formed can be generated. Thereby, for example, when the digital pen 60 comes into contact with the medium, the coordinate information is read, and the locus information (handwriting information) of the digital pen 60 is acquired from the coordinate information. Then, it is possible to determine whether the barcode is approaching by referring to the management information. And when it determines with approaching, a mode change can be performed from code image reading mode to barcode reading mode. In addition, acquisition of locus | trajectory information is performed by the handwriting information generation part 645 which functions as a locus | trajectory information acquisition means. When the mode changing unit 631 functioning as a switching unit refers to the management information and determines that the digital pen 60 is approaching the barcode based on the trajectory information, the mode is changed. Here, when moving in a direction not approaching the barcode, or when approaching but tilting with respect to the longitudinal direction of the barcode, a warning is displayed by the display control unit 633. Can do.

Even if the barcode reading mode is changed, the reading area may be in a state along the bar constituting the barcode as shown in FIG. That is, the barcode may be read while the digital pen 60 is rotated in the circumferential direction. In this case, it is difficult to obtain barcode information as described above. Therefore, for example, when the rotation amount of the digital pen 60 exceeds a predetermined value, for example, a warning display by the display control unit 633 can be performed. Note that the rotation (rotation amount) of the digital pen 60 in the circumferential direction can be detected based on recognition of the synchronization pattern, for example.
Further, when the digital pen 60 rotates in the circumferential direction, the reading area can be set in a state as shown in FIG. 16B before the barcode is read. That is, the rotation (rotation amount) of the electronic writing instrument with respect to the medium in the circumferential direction can be detected based on the synchronization pattern, and the reading area can be set based on the detection result.

It is the figure which showed an example of the structure of the handwriting information management system of this Embodiment. It is the block diagram which showed an example of the function structure of the document server. It is the figure which showed an example of the image etc. which comprise a code image. It is the block diagram which showed an example of the function structure of the identification information server. It is a figure explaining the functional structure of a digital pen. It is the block diagram which showed an example of the function structure of the control circuit. In a code image reading mode, operation until acquisition of handwriting information (handwriting data) is shown notionally. It is the figure which showed the hardware constitutions of the control part of a digital pen. It is the sequence diagram which showed an example of the operation | movement at the time of a printed document being produced | generated in a handwriting information management system. It is the sequence diagram which showed an example of operation | movement of the identification information server at the time of registering handwriting information, and a document server. It is the figure which showed the hardware constitutions of the computer. Fig. 2 conceptually shows an imaging area of a digital pen. Fig. 2 conceptually shows an imaging area of a digital pen. The basic processing in the barcode reading mode is shown. It shows a read image and the like when the digital pen rotates in the circumferential direction. It is a figure for demonstrating the change of a read-out area. It is the flowchart which showed the process performed in a control part. The medium and the digital pen are shown.

Explanation of symbols

60 ... Digital pen, 614 ... Infrared CMOS, 631 ... Mode change unit, 632 ... CMOS control unit, 644 ... Position information acquisition unit, 645 ... Handwriting information generation unit, 651 ... Image composition unit, 652 ... Intersection detection unit

Claims (13)

A plurality of light receiving elements arranged in a two-dimensional matrix, and an imaging unit that captures an image on a medium;
A first mode for capturing an image on the medium using a light receiving element included in a predetermined region of the imaging unit;
A second mode for capturing an image on the medium using a light receiving element included in an area smaller than the predetermined area of the imaging unit;
Switching means for switching between the first mode and the second mode;
An electronic writing instrument.   In the second mode, when a plurality of code images attached to the medium are picked up in pieces, image generation means for generating a composite image that reproduces the entire code image is further provided. The electronic writing instrument according to claim 1.   The electronic writing instrument according to claim 2, further comprising an information acquisition unit that acquires information related to the code image from the composite image generated by the image generation unit. Grasping means for grasping a density distribution in an image picked up in the second mode based on a signal from each of light receiving elements included in the small region;
Output means for outputting warning information when the concentration distribution grasped by the grasping means is not a predetermined distribution;
The electronic writing instrument according to claim 1, further comprising:   The electronic writing instrument according to claim 1, further comprising changing means for changing a position of the small area.   The electronic writing instrument according to claim 5, wherein the changing unit changes the position of the small area when the density distribution in the image captured in the second mode is not a predetermined distribution. In the first mode, when a code image indicating a position in the medium is captured from the medium, the apparatus further includes position information acquisition means for acquiring position information from the code image.
The switching means switches from the first mode to the second mode when the position information acquired by the position information acquisition means is predetermined position information. The electronic writing instrument according to any one of the above. In the first mode, when a code image indicating a position in the medium is captured from the medium, the information processing apparatus further includes trajectory information acquisition means for acquiring the trajectory information of the electronic writing instrument with respect to the medium based on the code image. ,
The switching means starts from the first mode when it is determined that the electronic writing instrument is approaching a code image attached to the medium based on the trajectory information acquired by the trajectory information acquisition means. The electronic writing instrument according to any one of claims 1 to 6, wherein the electronic writing instrument is switched to a second mode. An imaging unit having a plurality of light receiving elements;
A first reading mode for acquiring a signal output from a light receiving element in a first area including any one of the plurality of light receiving elements in the plurality of light receiving elements in the imaging unit;
A second reading mode for acquiring a signal output from a light receiving element in a second area composed of a plurality of light receiving elements smaller than the first area of the imaging unit;
An electronic writing instrument.   A third mode for acquiring a signal output from a light receiving element in a third area that is different from the second area and includes a plurality of light receiving elements smaller than the first area; The electronic writing instrument according to claim 9, wherein the electronic writing instrument is characterized in that:   The electronic writing instrument according to claim 10, wherein the third area is formed so as to intersect with the second area.   The electronic writing instrument according to claim 10 or 11, wherein the third area is formed so as to be substantially orthogonal to the second area. A first function of reading a signal from a light receiving element included in a predetermined region of an imaging unit having a plurality of light receiving elements;
A second function of reading a signal from a light receiving element included in an area smaller than the predetermined area of the imaging unit;
A program that makes a computer realize.

Images