JP2010160744A - Reading apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technology for improving the accuracy of reading an image to be read in a reading apparatus for reading the image to be read. <P>SOLUTION: An image forming part 80 of an optical unit 70 is freely rotatably supported by a rotation axis 72. The image forming part 80 is automatically rocked in an arrow M direction by a rock actuator. By this rock, an angle formed by an irradiation axis (a) and a light receiving axis (b) is changed and a focus distance in the image forming part 80 is changed. Thus, in an arrangement of the irradiation axis (a), the light receiving axis (b), and a medium 50, even when reflecting light received by the image forming part 80 becomes a specular reflection component, the light receiving axis (b) is shifted with respect to the irradiation axis (a) by rock operation of the image forming part 80. Then, the reflecting light to be a diffuse reflection component is received by the image forming part 80, an image readable by an image pickup part 64 is acquired, and reading errors are reduced. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a reader.

  In recent years, the writing content on paper has been converted into electronic writing information data at the same time, and this data is transferred to a personal computer, mobile phone, etc., and the written content is displayed on a monitor or transferred / saved as data. The technology to do is attracting attention. In this technology, there are special paper on which fine dots formed in different patterns on the surface are printed, and an electronic pen (Anotopen (registered trademark)) that converts the written contents into electronic information by reading these dots. Used. When writing is performed on special paper, this electronic pen reads a dot pattern in the vicinity of the pen tip with an imaging device, and specifies the position of the pen tip on the special paper from the read dot pattern. As a result, it is possible to generate an electronic document composed of written characters, graphics, etc., and to add characters, graphics, etc. to a predetermined electronic document (for example, see Patent Document 1). On the other hand, as a technique for reading a special pattern, there is a bar code reader (Patent Document 2) including a plurality of image sensors.

Japanese Patent Laying-Open No. 2004-94907 (pages 12-14) Japanese Utility Model Publication No. 2-183879

  An object of the present invention is to improve the reading accuracy of an image to be read in a reading device that reads the image to be read.

  In order to achieve the above-described object, the configuration of the reading apparatus employed by claim 1 of the present invention is configured to indicate an instruction unit that indicates a position on a medium on which a read image to be read is formed, and an instruction by the instruction unit. Irradiating means for irradiating light on a predetermined irradiation range with respect to a position on the medium, imaging means for receiving reflected light of the light irradiated on the medium by the irradiating means, and the imaging means An imaging device that captures an image to be read on the basis of the reflected light received by the generator and generates a signal representing the image to be read; and an irradiation that is irradiated with light by the irradiation unit while changing the posture of the imaging unit Changing means for changing the position of the read image captured by the generating means within a range.

  According to a second aspect of the present invention, there is provided the reader according to the first aspect, wherein the changing means includes a rotating shaft that rotatably supports the imaging means, and the imaging means around the rotating axis. Drive means for swinging within a predetermined range.

  According to the first aspect of the present invention, it is possible to suppress deterioration in reading accuracy due to a large amount of regular reflection components in reflected light from a medium and a lack of focus when an image to be read is captured.

  According to the second aspect of the present invention, the posture can be varied by swinging the imaging means.

It is a figure which shows the whole structure of a writing information processing system. It is a figure which shows the content of the code pattern image. It is a functional block diagram which shows the structure of an electronic pen. It is sectional drawing which shows the structure of an electronic pen. It is a functional block diagram which shows the control part of an electronic pen. It is the figure which showed the output timing chart regarding an illumination control signal, an image capture signal, and an output image signal. It is the flowchart which showed the operation | movement in the code | cord | chord detection part and data processing part of an electronic pen. It is the figure which showed typically the irradiation axis a and irradiation range A of an irradiation part, and the light-receiving axis b and imaging range B of an image formation part. It is a figure which shows an example of the content of writing with an electronic pen. It is a figure which shows an example of the transition of the imaging range by the imaging part of an electronic pen. It is the characteristic line figure which showed the conventional readable area | region typically. FIG. 6 is a characteristic diagram schematically illustrating a readable area in the embodiment.

<A: Configuration>
FIG. 1 is a diagram illustrating an example of a configuration of a system according to the present embodiment. In the figure, an electronic pen 60 has a function of writing characters and figures on a medium 50 such as paper, and a reading device having a function of reading a code pattern image (read image) formed on the medium 50. It is an example. The information processing apparatus 10 is a personal computer, for example, and is an example of a writing information generation apparatus that generates writing information representing writing contents in accordance with a signal output from the electronic pen 60.

  The code pattern image formed on the medium 50 is an image obtained by encoding identification information for identifying the medium 50 and position information indicating coordinate positions on the medium 50. Here, an example of the code pattern image formed on the medium 50 will be described with reference to FIG. FIG. 2 is a diagram illustrating an example of a code pattern image formed on the medium 50. The code pattern image represents the above-described identification information and position information by the mutual positional relationship between a plurality of dot-like dot images. As the areas where these dot images can be arranged, areas A1 to A9 are preliminarily provided. It has been established. In the example shown in FIG. 2, black areas A1 and A2 indicate areas where dot-like dot images are arranged, and hatched areas A3 to A9 indicate areas where dot images are not arranged. The identification information and the position information are expressed depending on which region the dot image is arranged. The code pattern image is formed on the entire medium 50 by an electrophotographic image forming apparatus (not shown) such as a printer. The electronic pen 60 reads the code pattern image, and then analyzes the code pattern image to detect the position of the pen tip 69a of the electronic pen 60.

In addition to the above-described code pattern image, the medium 50 may be formed with an image such as a document or a figure intended to convey information to a person.
Hereinafter, this image is referred to as a “document image”, but this is not limited to an image representing a document including text, and includes, for example, an image such as a picture, a photograph, or a graphic, and other images. When forming a code pattern image, the image forming apparatus uses K (black) toner to form an image, while when forming a document image, C (cyan), M (magenta), and Y (yellow). Image formation is performed using toner. On the medium 50, a document image and a code pattern image are superimposed and formed. Thus, by forming the code pattern image and the document image using materials having different spectral reflection characteristics, the electronic pen 60 can be set to selectively read only the code pattern image.
The “medium” in the present embodiment is not limited to so-called paper, and may be a plastic sheet such as an OHP sheet, a sheet made of other materials, or the like. Moreover, what is called electronic paper which can electrically rewrite display content may be used. In short, the medium 50 may be any medium on which at least a code pattern image is formed by an image forming apparatus or the like.

  The electronic pen 60 is a writing instrument having a function of writing characters, figures, and the like on the medium 50 and is a reading device that reads a code pattern image formed on the medium 50. The electronic pen 60 transmits information indicating the code pattern image read from the medium 50 to the information processing apparatus 10.

  Next, an example of a functional configuration of the electronic pen 60 will be described with reference to the drawings. FIG. 3 is a functional block diagram schematically showing functions of the electronic pen 60. In the figure, a control unit 61 is a control unit that controls the overall operation of the electronic pen 60. The pressure sensor 62 is a detection unit that detects a writing operation by the electronic pen 60 by a pressure applied to the pen tip 69. The optical system unit 70 includes an irradiation unit 63, an imaging unit 80, and an imaging unit 64. The irradiation unit 63 is, for example, a near infrared LED, and is an example of an irradiation unit that irradiates the medium 50 with near infrared light. The imaging unit 80 is an example of an imaging unit that forms an image on the medium 50 on the imaging unit 64 in accordance with the reflected light reflected by the medium 50. The imaging unit 64 is an example of a generating unit that captures an image on the medium 50 according to the reflected light of the near infrared light emitted from the irradiation unit 63.

The information memory 65 is a storage unit that stores identification information and position information. The communication unit 66 is a communication unit that controls communication with an external device. The battery 67 is a rechargeable power supply unit that supplies power for driving the electronic pen 60 to each unit. The pen ID memory 68 is a storage unit that stores identification information (pen ID) of the electronic pen 60. The pen tip 69 is a so-called pen shaft, and the tip portion thereof becomes a pen tip 69a. The pen tip 69a serves as an instruction unit that indicates a position on the medium 50 on which a code pattern image (read image) to be read is formed when a writing operation is performed by the user. When the writing operation is performed by the user, the irradiation unit 63 irradiates light to a predetermined irradiation range with respect to a position on the medium 50 indicated by the pen tip 69a. In the drawing, for the sake of convenience, only the center line of the light emitted from the irradiation unit 63 is illustrated, but in actuality, irradiation is performed in a diffuse state. The switch 75 is a switching unit that switches various settings.
Each of these units is connected to the control unit 61. Further, a swing actuator 81 for swinging an imaging unit 80 described later is connected to the control unit 61.

Next, an example of the configuration of the pen tip 69 and the optical system unit 70 will be described with reference to the drawings. FIG. 4 is a cross-sectional view showing a schematic configuration of the electronic pen 60.
The pen tip 69 is provided in a pen main body 60A serving as a housing of the electronic pen 60, and a pressure sensor 62 is disposed on the starting end side. The pen tip 69 is movable toward the leading end side by a force applied to the pen tip 69a, and the pressure sensor 62 detects that the pen tip 69 has been moved by the writing pressure, whereby the pen tip 69a has a force. Detect that it has been added.

  The optical system unit 70 is accommodated on the start side of the pen tip 69 in the pen body 60A. The optical system unit 70 includes an irradiation unit 63, an imaging unit 80 that is rotatably supported by the rotation shaft 72 of the unit case 71, and an image formed on the imaging unit 63 on the medium 50 by reflected light. An imaging unit 64 that converts the signal into an electrical signal, and the irradiation unit 63 and the imaging unit 64 are fixed to the unit case 71. The rotating shaft 72 extends in a direction orthogonal to the optical axis irradiated from the irradiation unit 63 toward the medium. Here, for convenience, the optical axis of the light emitted from the irradiation unit 63 is referred to as an irradiation axis a, and the central axis of the imaging optical system of the imaging unit 80 is referred to as a light receiving axis b. The direction of the light receiving axis b here is basically the direction of the light receiving surface, and is typically on the medium 50 imaged by the imaging unit 80 and imaged by the imaging unit 64. This is a direction connecting the center of the region (hereinafter referred to as the imaging range imaging range).

  The imaging unit 64 includes a substrate 64A on which electronic components are mounted, an imaging device 64B mounted on the substrate 64A, and a prism 64C that reflects the light imaged by the imaging unit 80 and guides it to the imaging device 64B. . The imaging element 64B captures a code pattern image based on the reflected light of the surface to be read formed by the imaging unit 63, and outputs a signal representing the captured code pattern image. Here, the imaging element 64B is a CMOS image sensor having sensitivity in the near-infrared region, and a global shutter CMOS image sensor that can generate image signals captured at the same timing in all pixels is used. The image sensor 64B captures an image according to an image capture period (frame rate) of about 70 fps to 100 fps (frame per second). Here, the irradiation unit 80 is configured to perform pulse lighting in synchronization with an image capturing period to the image sensor 64B in order to suppress power consumption. Although a CMOS image sensor is used here as the image sensor, the image sensor is not limited to a CMOS image sensor, and other image sensors such as a C copier image sensor may be used.

  The imaging unit 80 includes a convex lens 80A that is a light receiving surface, and a lens support member 80B that supports the convex lens 80A. The imaging unit 80 captures an image on the medium 50 on the imaging unit 64 according to reflected light. This is an example of an image forming means for forming an image. The lens support member 80 is rotatably supported by the rotation shaft 72 of the optical system unit 70, and the swing actuator 81 swings the lens support member 80 in the arrow M direction. The swing actuator 81 includes a combination of a rotary motor and a swing slider mechanism, or a linear actuator. The swing actuator 81 and the rotating shaft 72 constitute an example of a changing unit.

  By swinging the imaging unit 80, the imaging range on the medium 50 is changed and the focal length is changed as shown in FIG. FIG. 8 is a diagram schematically illustrating an irradiation range A in which the irradiation unit 63 is irradiated toward the medium 50 and an imaging range B in the imaging unit 80. An irradiation range A indicates a range in which light from the irradiation unit 63 is irradiated, and an imaging range B is a range having a focal length (so-called depth of field) of the imaging unit 80, that is, a state where an image is focused. This is the range where light is received. Therefore, the direction of the light receiving axis b is the longitudinal direction of the housing of the electronic pen 60.

First, FIG. 8 (b) shows the positive line generated when the normal line c with respect to the medium 50 and the central axis obtained by dividing the angle formed by each axis at the point where the irradiation axis a and the light receiving axis b intersect. In this case, the reflected light received by the image forming unit 80 becomes a regular reflection component, so that a reading error often occurs. On the other hand, in FIG. 8A, the imaging range B moves to the right compared to the imaging range B in FIG. 8B, and in FIG. 8C, the imaging range B is the imaging range in FIG. 8B. Move to the left compared to range B. In FIGS. 8A and 8C, since the imaging range B is deviated from the irradiation axis a, the reflected light received by the imaging unit 80 has a large amount of diffuse reflection components, so that a reading error occurs. Decreases and reading accuracy improves.
Here, in FIG. 8A or FIG. 8C, the imaging unit 80 receives reflected light at a position deviated from the position where the focal length and the read image on the medium 50 coincide with each other (just focus position). However, either one of FIGS. 8A and 8C close to the just focus is selected and used for reading.

  Next, an operation example when the user writes the points illustrated in FIG. 9 on the medium 50 using the electronic pen 60 will be described. The user indicates the position (x1, y1) on the medium 50 with the electronic pen 60 and presses the pen tip 69a against the medium 50. Thereby, the pressure sensor 62 connected to the pen tip 69 detects the writing operation, and starts the reading process of the identification information and the position information. At this time, the image forming unit 80 starts to swing in the direction of arrow M due to the pushing operation of the pen tip 69a by the user.

FIG. 10 is a diagram illustrating an example of the transition of the imaging range B by the imaging unit 80. FIG. 10 is a diagram schematically showing the transition of the imaging range B corresponding to the writing operation shown in FIG. In FIG. 10, in order to prevent the drawing from becoming complicated, the number of imaging ranges B by the optical system unit 70 is shown by a number smaller than the number of actually captured images. In conjunction with the operation of the pen tip 69a being pushed in by the user at the position (x1, y1) shown in FIG. Change.
In particular, in a conventional electronic pen, if a certain point on the medium 50 is indicated and the imaging unit 1641 receives a large amount of specular reflection components, the code pattern image cannot be read accurately and a reading error occurs. As a result, information on the writing operation is lost.

  On the other hand, the imaging unit 80 of the electronic pen 60 of the present embodiment performs imaging in a plurality of imaging ranges at a plurality of different light receiving angles even when the user designates a certain point on the medium 50. (Refer to regions B1 to B7 in FIG. 10). At this time, as described above, the intersection angle between the irradiation axis a of the irradiation unit 63 and the light receiving axis b of the imaging unit 80 with respect to the medium 50 is different in each of the regions B1, B2,. By selecting an image close to the just focus from the captured image to be read, even when a large amount of regular reflection components are received, reading errors can be reduced and reading accuracy can be improved.

  Next, when a continuous line is drawn on the medium 50, an imaging range is formed while overlapping like a triangular wave waveform in the direction in which the pen tip 69 moves. By selecting an image close to the just focus among images captured in these imaging ranges, even if a large amount of regular reflection components are received, reading errors can be reduced and reading accuracy can be improved. it can.

  Next, the functional configuration of the control unit 61 will be described with reference to FIG. FIG. 5 is a functional block diagram illustrating functions of the control unit 61. In the figure, a code detection unit 612 detects a code pattern image from a signal output from the imaging unit 64 (a signal representing a captured image). The data processing unit 613 extracts identification information and position information from the code pattern image detected by the code detection unit 612. The illumination control unit 614 transmits an illumination control signal for illuminating the irradiation unit 63 to the irradiation unit 63 to cause the irradiation unit 63 to perform pulse lighting. The imaging control unit 615 supplies the imaging unit 64 with an image capture signal synchronized with the pulse lighting transmitted to the irradiation unit 63.

Furthermore, an outline of the operation of the control unit 61 in the electronic pen 60 will be described. FIG. 6 is a timing chart showing an output related to an illumination control signal for controlling the pulse lighting of the irradiation unit 63, an image capture signal in the imaging unit 64, and an output image signal. When writing with the electronic pen 60 is started, the pressure sensor 62 connected to the pen tip 69 detects the writing operation. Thereby, the control part 61 starts the reading process of identification information and position information.
First, the illumination control unit 614 of the control unit 61 transmits an illumination control signal (FIG. 6A) for turning on the irradiation unit 63 in a pulsed manner to the irradiation unit 63, and turns on the irradiation unit 63 in a pulsed manner.

  The imaging unit 64 captures an image on the medium 50 in synchronization with the image capture signal (FIG. 6B). At that time, the irradiation unit 63 is pulse-lit in synchronization with the image capture signal to the imaging unit 64. The imaging unit 64 captures an image on the medium 50 illuminated by the irradiation unit 63 that performs pulse lighting. Therefore, in the imaging unit 64, image signals (output image signal: FIG. 6C) relating to the image on the medium 50 illuminated by the irradiation unit 63 are generated in order.

  Output image signals sequentially generated by the imaging unit 64 are sent to the code detection unit 612. The code detection unit 612 that has received the output image signal processes the output image signal and detects a code pattern image from the image captured by the imaging unit 64. The code pattern image acquired by the code detection unit 612 is sent to the data processing unit 613. Upon receiving the code pattern image, the data processing unit 613 decodes the code pattern image and acquires identification information and position information embedded in the code pattern image.

<B: Operation>
Next, the operation of the electronic pen 60 according to this embodiment will be described. When the user starts writing with the electronic pen 60, the pressure sensor 62 connected to the pen tip 69 detects the writing operation.
In this operation example, an operation example in which the user writes the points illustrated in FIG. 9 on the medium 50 using the electronic pen 60 will be described. The user indicates the position (x1, y1) on the medium 50 with the electronic pen 60 and presses the pen tip 69a against the medium 50. Thereby, the pressure sensor 62 connected to the pen tip 69 detects the writing operation, and the control unit 61 starts the reading process of the identification information and the position information.

  First, the illumination control unit 614 transmits an illumination control signal for pulse-lighting the irradiation unit 63 to the irradiation unit 63, and causes the irradiation unit 63 to pulse-light. Further, the imaging control unit 615 of the electronic pen 60 supplies the imaging unit 64 with an image capture signal synchronized with the pulse lighting transmitted to the irradiation unit 63. The imaging unit 64 captures the code pattern image based on the reflected light imaged by the imaging unit 64 in accordance with the image capture signal supplied from the imaging control unit 615, and outputs the captured code pattern image The image signal is output to the code detection unit 612.

  Next, operations of the code detection unit 612 and the data processing unit 613 will be described with reference to the flowchart shown in FIG. An output image signal representing an image on the medium 50 is input from the imaging unit 64 to the code detection unit 612 (step 601). The code detection unit 612 performs processing for removing noise included in the output image signal (step 602). Here, the noise includes variations in CMOS sensitivity, noise generated by an electronic circuit, and the like. What processing is performed to remove noise is determined according to the characteristics of the imaging system of the electronic pen 60. For example, sharpening processing such as blurring processing or unsharp masking can be applied. Next, the code detection unit 612 detects a dot pattern (position of the dot image) from the image (step 603). In addition, the code detection unit 612 converts the detected dot pattern into digital data on a two-dimensional array (step 604). For example, on a two-dimensional array, a position where there is a dot is converted to “1”, and a position where there is no dot is converted to “0”. The digital data (code pattern image) on the two-dimensional array is transferred from the code detection unit 612 to the data processing unit 613.

  The data processing unit 613 detects a dot pattern composed of a combination of two dots shown in FIG. 2 from the delivered code pattern image (step 605). For example, the dot pattern can be detected by moving the boundary position of the block corresponding to the dot pattern on the two-dimensional array and detecting the boundary position where the number of dots included in the block is two. When the dot pattern is detected in this way, the data processing unit 613 detects the identification code and the position code based on the type of the dot pattern (step 606). Thereafter, the data processing unit 613 acquires the identification information by decoding the identification code, and acquires the position information by decoding the position code (step 607). In the processing shown in FIG. 7, when the light amount received by the imaging unit 80 is too small or when the light amount received is too large, the dot pattern is not detected from the captured image, and the electronic pen 60 is A case where identification information and position information cannot be acquired (that is, a reading error) occurs. When the identification information and the position information cannot be acquired as described above, the data processing unit 613 acquires reading error information indicating a reading failure instead of the identification information and the position information.

  The electronic pen 60 transmits the identification information and position information acquired by the processing of FIG. At this time, if the reading of the identification information and the position information fails, the electronic pen 60 transmits information indicating the reading failure to the information processing apparatus 10. The information processing apparatus 10 receives identification information and position information from the electronic pen 60, and generates writing information based on the received position information. When the information processing apparatus 10 receives information indicating a reading error from the electronic pen 60, the information processing apparatus 10 generates writing information by interpolating the identification information and the position information before and after the information.

<C: Example of operation>
Next, an example of a specific operation of this embodiment will be described with reference to the drawings. In the electronic pen 60 according to the present embodiment, the swinging operation of the image forming unit 80 is started by the swing actuator 81. As a result, as shown in the schematic diagram of FIG. 8, the imaging range B of the imaging unit 80 swings within the irradiation range A of the irradiation unit 63. Then, the reflected light at the position deviated from the position where the focal length and the read image on the medium 50 coincide (just focus) is read by the imaging unit 64, thereby reducing reading errors and improving the reading accuracy of the read image. improves.

  By the way, normally, in order to improve the imaging efficiency in the electronic pen, an autofocus mechanism is employed in the image forming unit. Some of the autofocus mechanisms adjust (focus) the focal length with respect to the medium 50 by changing the distance between a plurality of lenses constituting the imaging unit along the light receiving axis.

Since the electronic pen starts a detection operation in the optical system unit by an operation written by the user, it is usually used in a state tilted to some extent. However, depending on the user's writing habit, such as when using a left-handed user while writing while checking his / her character, use the electronic pen in a state orthogonal to the medium. Sometimes.
In such a case, in the electronic pen, since the pen tip 69 and the optical system unit 70 are arranged side by side in the coaxial direction, the normal line to the medium 50, the irradiation axis a, and the light receiving axis as shown in FIG. When b intersects with the central axis obtained by dividing the angle formed by each axis into two, the reflected light received by the imaging unit 80 becomes a regular reflection component, and the code pattern image is accurately There may be many reading errors that cannot be read.
In addition, since the autofocus mechanism described above focuses by moving the lens along the light receiving axis, autofocusing (focusing) at the position where the specular reflection component is received avoids reading errors. I couldn't.

  On the other hand, since the electronic pen 60 according to the present embodiment changes the angle formed by the irradiation axis a and the light receiving axis b by swinging the imaging unit 80, the regular reflection component in the imaging unit 80 is changed. Reading errors are reduced by receiving more reflected light of the diffuse reflection component than the reflected light.

Specific examples are shown in FIGS. 11 and 12 are diagrams schematically showing a readable region and a non-readable region with respect to the focal length of the imaging unit 80 and the angle of the light receiving axis b with respect to the medium 50.
The focal point on the horizontal axis indicates the focal length that is changed by moving a part in the imaging unit, and the angle on the vertical axis indicates the angle of the electronic pen 60 with respect to the medium 50.
The regular reflection angle is an angle at which the normal line to the medium 50 and the central axis that bisects the angle formed by each axis at the point where the irradiation axis a and the light receiving axis b intersect.

  FIG. 11 is a characteristic diagram showing the characteristics of focusing (moving the focal length) by the autofocus mechanism that is performed by moving the lens in the above-described imaging section along the light receiving axis b. A double-sided arrow line extending horizontally indicates a range to be focused for each angle. Thus, since only the focal length can be changed by this autofocus mechanism, each double-sided arrow line extends in the horizontal direction. At the regular reflection angle, the autofocus mechanism only moves the focal length within the unreadable area, and thus an unreadable image captured by the reflected light.

  FIG. 12 is a characteristic diagram showing the characteristics of focusing (moving the focal length) when the imaging unit 80 is swung by the electronic pen 60 of the present embodiment. Since the angle formed by the irradiation axis a and the light receiving axis b is changed by the swinging operation of the imaging unit 80, the angle of the light receiving axis b with respect to the medium 50 and the focal length are changed along with the swinging operation of the imaging unit. Will change. For this reason, the double-sided arrow line is drawn inclining obliquely. When the regular reflection angle is reached, the imaging unit 64 captures the reflected light received in the readable region that is deviated from the position where the focal length and the image to be read on the medium 50 match (just focus position). . Thereby, the imaging unit 80 and the imaging unit 64 can acquire a readable image, and as a result, reading errors in the imaging unit 64 can be reduced.

<D: Modification>
As mentioned above, although embodiment of this invention was described, this invention is not limited to embodiment mentioned above, It can implement with another various form. An example is shown below. In addition, you may combine each following aspect.
(1) In the above-described embodiment, the electronic pen that writes characters, figures, and the like on the medium 50 has been described. However, the present invention is not limited to this, and for example, corresponds to a pointing device (mouse) function or an area on the medium. It may be provided with a stylus function for reading the recorded information (for example, command information).
In addition, although the operation example in the case of writing a character etc. on the medium 50 was demonstrated in the operation example of embodiment, it is not restricted to this, For example, display screens, such as selecting the soft button provided on the medium 50, etc. The electronic pen 60 of this embodiment is also effective when simply specifying the upper position.

(2) In the above-described embodiment, a near infrared LED that irradiates near infrared light is used as the irradiation unit 63. However, the irradiation unit 63 is not limited to this, and an LED having different characteristics may be used. Good. In short, the irradiating unit 63 only needs to irradiate the code pattern image formed on the medium 50 with light that can be read by the reflected light.

(3) In the above-described embodiment, information that uniquely identifies a medium is used as identification information. However, the identification information is not limited to this, and for example, information that uniquely identifies an electronic document is used as identification information. May be. When information that uniquely identifies a medium is used as exemplified in the first embodiment, different identification information is assigned to different media when a plurality of copies of the same electronic document are formed. On the other hand, when information that uniquely identifies an electronic document is used as identification information, the same identification information is given to different media when the same electronic document is formed.

  In the above-described embodiment, the code pattern image representing the position information and the identification information is read. However, the information represented by the code pattern image is not limited to the position information and the identification information, but is, for example, information representing text data or a command. May be. Alternatively, the image may represent only position information. In short, an image representing some information may be formed on the medium 50.

(4) In the image forming apparatus described above, the code pattern image is formed using K toner. This is because the K toner has a larger amount of infrared light absorption than the C, M, and Y toners, and the code pattern image can be read with high contrast by the electronic pen 60. However, the code pattern 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 based on whether or not an image formed on the formed medium can be recognized by the presence or absence of color development due to absorption of a specific wavelength in the visible light region. Further, “invisible” includes those that have some color developability due to absorption of a specific wavelength in the visible light region but are difficult to recognize with human eyes. The invisible toner preferably has an average dispersion diameter in the range of 100 nm to 600 nm in order to increase the near infrared light absorption capability necessary for machine reading of an image.
Further, the image forming apparatus is not limited to the electrophotographic system, and any other system such as an ink jet system may be used.

(5) A computer program executed by the control unit 61 of the electronic pen 60 according to the above-described embodiment includes a magnetic recording medium (magnetic tape, magnetic disk, etc.), an optical recording medium (optical disk, etc.), a magneto-optical recording medium, and a semiconductor. It may be provided in a state stored in a computer-readable recording medium such as a memory. It is also possible to download to the electronic pen 60 via a network such as the Internet. Various devices other than the CPU can be applied as the control means for performing the above-described control. For example, a dedicated processor or the like may be used.

DESCRIPTION OF SYMBOLS 10 ... Information processing apparatus, 50 ... Medium, 60 ... Electronic pen, 61 ... Control part, 62 ... Pressure sensor, 63 ... Irradiation part, 64 ... Imaging part, 64A ... Substrate, 64B ... Imaging element, 64C ... Prism, 65 ... Information memory, 66 ... communication unit, 67 ... battery, 68 ... pen ID memory, 69 ... pen tip, 69a ... pen tip, 70 ... optical system unit, 71 ... unit case, 72 ... rotating shaft, 75 ... switch, 80 ... connection Image section, 80A ... convex lens, 80B ... lens support member, 81 ... swing actuator, 612 ... code detection section, 613 ... data processing section, 614 ... illumination control section, 615 ... imaging control section, a ... irradiation axis, A ... Irradiation range, b: light receiving axis, B: imaging range.

Claims (2)

An instruction unit for instructing a position on a medium on which a read image to be read is formed;
Irradiating means for irradiating light to a predetermined irradiation range with respect to a position on the medium instructed by the instruction unit;
Imaging means for imaging reflected light from the medium irradiated with light by the irradiation means;
Generating means for generating a signal representing the read image according to the reflected light imaged by the imaging means;
And changing means for changing the position of the read image captured by the generating means within the irradiation range irradiated with light by the irradiating means by changing the posture of the imaging means. Reader. The reading device according to claim 1.
The changing unit includes a rotation shaft that rotatably supports the imaging unit, and a driving unit that swings the imaging unit within a predetermined range around the rotation axis. Reader.

Images