KR101949046B1 - Handwriting input device - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an input device, and more particularly, to a device capable of inputting a handwriting using a hand or an electronic pen. The present invention relates to a handwriting input device for inputting handwriting by a moving subject on an input surface of various fixed subjects, the handwriting input device comprising a camera for photographing the moving subject and the input surface at the same time to acquire a photographing image having a reference point, A first reference area which is a region in which a reference point of the photographed image can be arranged when the entire input surface of the article enters a field of view (FOV) of the camera, And a reference image storage unit for storing a reference image having a second reference area centered at a position of an ideal reference point, wherein the reference image is compared with the reference image, And a second determination unit for determining whether the reference point is located within the second reference area And a controller for calculating a position coordinate of a moving subject using the photographed image, wherein when the edge of the fixed subject is not recognized in the photographed image, And calculates the position coordinates of the moving subject only when it is determined that the reference point of the captured image is located within the second reference area.

Description

[Technical Field] The present invention relates to a handwriting input device,

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an input device, and more particularly, to a device capable of inputting a handwriting using a hand or an electronic pen.

2. Description of the Related Art As a method of inputting information into an electronic device such as a computer or a portable terminal, an input method such as a mouse and a keyboard has been used. Recently, an input method using a touch screen has been widely used.

The input method using the touch screen is a new input method which can replace the input method of a mouse or a keyboard, and is an input method in which information can be inputted directly to the screen by using a hand or a pen. The input method using the touch screen is evaluated as the most ideal input method in GUI (Graphical User Interface) environment because the user can directly perform the desired operation while viewing the screen and anyone can easily operate it. It is widely used in various fields such as terminal of public office, medical equipment, guide display device of tourist agency.

In addition, technologies and products capable of recognizing the handwriting of a user by using an electronic pen in another manner and digitizing and storing the recognized contents are being commercialized. In a conventional pen-type character input system, a microcode representing a coordinate on a paper for character input is inserted in advance, and a motion locus of the pen is estimated through an optical position recognition technique.

For example, in Japanese Laid-Open Patent Publication No. 2010-52526, a transparent sheet having a dot pattern including absolute coordinate information is attached to a display screen of an electronic device, and then the dot pattern is read using an optical reading device, An information processing system capable of inputting a form similar to that of FIG.

The conventional input system using the dot pattern recognizes the position of the optical reading device by directly using the absolute coordinate information included in the coordinate pattern read by the optical reading device.

Therefore, there has been a problem that the coordinate pattern must be arranged very closely for accurate and delicate input. For example, if the coordinate pattern is printed at 300 dpi, the coordinate pattern should be arranged at intervals of about 84 탆. Such a tightly arranged coordinate pattern has a problem that the transparency of the display screen can be lowered. In addition, since the shape of the coordinate pattern is complicated, and the size is very small and the number is large, it is also difficult to form a coordinate pattern. In addition, even if a coordinate pattern is formed, a film having a coordinate pattern formed therein can be deformed during the course of production such as coordinate pattern printing, protective layer coating, and the like, and an error of several tens of micrometers may occur in the process of attaching the film.

In addition, there is a problem that even if the closely-arranged coordinate pattern is used, distortion of the image photographed by the camera occurs in accordance with the attitude of holding the electronic pen, thereby making it difficult to accurately measure coordinates.

In addition, Japanese Patent Application No. 10-1312018 discloses a technique of confirming the position of an electronic pen moving on a transparent panel using an infrared camera without using a separate coordinate pattern, and then locating the trajectory of the electronic pen on a flat panel display device positioned below the transparent panel And a display unit for displaying the image data. Such a system has a problem that the measurement accuracy is too low and the reaction rate is slow.

In other absolute coordinate type electronic pens, letters were written on a tablet or electronic pad capable of recognizing coordinates using an electronic pen, and characters were input by recognizing coordinates by movement of the electronic pen and restoring the locus. This absolute coordinate-based approach has the problem that an additional reference system (i.e., a tablet or electronic pad) is required to provide absolute coordinates, although the pen trajectory reconstruction is relatively well performed.

In order to overcome this problem, an attempt has been made for a coordinate input based character input method instead of an absolute coordinate method by utilizing an inertial sensor or an optical sensor. As an example, a system using a pen-shaped optical mouse is proposed, in which a trajectory is restored by calculating the movement of a pen-tip using only an inertial sensor. However, this technique has a problem that cumulative error increases with time, and there is a problem that the absolute coordinates can not be known.

Japanese Patent Application Laid-Open No. 2010-52526 Patent No. 10-1312018

SUMMARY OF THE INVENTION It is an object of the present invention to provide an input system capable of precise and delicate input without using a coordinate pattern.

According to another aspect of the present invention, there is provided a handwriting input device for inputting handwriting by a moving subject on an input surface of various fixed subjects, the handwriting input device comprising: A reference point of the photographed image may be arranged when the entire entry surface of the article enters a field of view (FOV) of the camera, the position recognition device being detachably installed in the fixed subject, And a reference image storing unit that stores a reference image in which a second reference area around the position of an ideal reference point is displayed, the reference image storing unit including a reference image storing unit storing the reference image, A first judging unit for judging whether the reference point is located inside the region, And a second determination unit for determining whether the reference point is located in a portion of the captured image, wherein the controller calculates a position coordinate of the moving subject using the captured image, wherein the controller determines that the edge of the fixed subject is not recognized When the second determining unit determines that the reference point of the photographed image is located within the second reference area, the position coordinate of the moving subject is calculated.

The handwriting input device according to the present invention has an advantage that accurate and delicate input can be performed without using a coordinate pattern.

1 is a view illustrating a method of mounting an input system according to an embodiment of the present invention on a fixed subject.
2 is a conceptual diagram of an electronic pen as an example of the moving subject shown in FIG.
3 is a conceptual diagram of the position recognition apparatus shown in Fig.
4A and 4B are conceptual diagrams of the clip portion shown in FIG.
5 is a block diagram of the controller shown in FIG.
6 is a view showing a reference image.
7 is a view showing a photographed image.
8 is a view showing a subject template.
9 is a view showing a matching image.
10 is a diagram showing a correction image.
11 is a conceptual diagram of other examples of the position recognition apparatus.
12 is an exemplary diagram showing a position recognition apparatus applied to a large display.
13 is a conceptual diagram of the position recognition apparatus shown in Fig.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. It will be apparent to those skilled in the art that the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, It is provided to let you know. Like reference numerals refer to like elements throughout.

1 is a view illustrating a method of mounting an input system according to an embodiment of the present invention on a fixed subject. Referring to Fig. 1, an embodiment of an input system according to the present invention includes an electronic pen 10, a position recognition device 20, and a controller 30. Fig.

The booklet 1 is an example of a fixed object to which the position recognition device 20 is attached and provides an input surface on which the pen tip 11 of the electronic pen 10 as a moving subject moves while being in contact. As the fixed subject, not only the notebook but also a variety of items including flat paper such as A4 paper, book, tablet, smart phone, large display and the like can be used.

2 is a conceptual view of the electronic pen shown in Fig. As shown in Fig. 2, the electronic pen 10 includes a pen tip 11, a housing 12, and a mouse module 13. And an infrared pointer 14.

The electronic pen 10 does not provide information on the current coordinates of the pen tip 11 but can provide information on the relative coordinates of the pen tip 11 on the basis of the current position.

The pen tip 11 is connected to a pressure sensor (not shown) and can act as an on / off switch of the electronic pen 10. The housing 12 of the electronic pen 10 may be provided with a mouse module 13 and an infrared pointer 14 for irradiating the pen tip 11. [

The mouse module 13 may be, for example, a laser mouse module including a laser diode and a laser sensor, an infrared light emitting diode, an optical mouse module including an optical image sensor and lenses, and an inertial mouse module using an inertial sensor. The mouse module 13 serves to obtain relative coordinate information of the movement trajectory of the pen tip 11. The mouse module 13 is provided with a microprocessor, a memory, and a communication module for controlling and communicating a light source such as a laser diode or an infrared light emitting diode. The communication module is connected to the controller 30 to transmit relative coordinate information of the pen tip 11 and can be connected to an I / O interface such as a USB port by wire or wirelessly via Bluetooth or Zigbee have. When connected wirelessly, a battery for supplying power is installed in the housing.

The infrared pointer 14 irradiates the pen tip 11 with infrared rays. The infrared pointer 14 may include an infrared light emitting diode and a condenser lens. When the optical mouse module is used as the mouse module 13, the infrared pointer 14 may collect a part of the light emitted from the light emitting diode of the mouse module 13 and irradiate the light onto the pen tip 11. [ The infrared pointer 14 is installed to easily acquire the image of the pen tip 11 using the infrared camera 22 of the position recognition device 20 described later. In addition, the infrared pointer 14 may irradiate infrared rays in the form of a pulse so that the controller 30 can distinguish the infrared rays from the external infrared ray and the infrared ray from the infrared ray pointer 14.

The electronic pen 10 may be provided with a button 15 for switching the function of the electronic pen 10 from a mouse function to a writing function or vice versa. When the mouse function is selected, it is not necessary to know the position of the pen tip 11, so that the infrared pointer 13 can be turned off.

In addition, the electronic pen 10 may be provided with a ballpoint pen which can be alternately selected from the pen tip 11, and a microphone module may be provided.

3 is a conceptual diagram of the position recognition apparatus shown in Fig.

The position recognition device 20 shown in Fig. 3 can be coupled to the rear end of the electronic pen 10 shown in Fig.

The position recognizing device 20 acquires a photographing image for recognizing the position of the pen tip 11 of the electronic pen 10, which is a moving subject, on the input surface of the fixed subject. The position recognition apparatus 20 includes a body 21, a camera 22, and a laser pointer 23. [ As shown in Fig. 1, the position recognition device 20 is mounted on one side of the notebook 1. The position recognition device 20 may be mounted on the edge of the notebook 1.

The body 21 is provided with a clip portion 25 for fixing the position recognition device 20 to the notebook 1 and includes a microprocessor 22 for controlling the camera 22 and the laser pointer 23, , A memory, and a communication module. Further, a light emitting diode 26 for identifying the user whether the position recognizing apparatus 20 is mounted in the correct position may also be provided.

The clip portion 25 has a structure for fixing the position recognition device 20 in a horizontal state regardless of the thickness of the book 1. The clip portion 25 includes a clip body 251, a support bar 252 extending from the clip body 251 and contacting the lower surface of the notebook, A vertical bar 253 inserted in the vertical groove 27 for guiding vertical movement of the clip body 251, a roller 254 fitted in a guide groove 28 elongated in the position recognizing device 20, Elastic supporting means 255 connected to the roller body 251 to provide elastic force to the roller 254 in a direction in which the roller 254 is away from the clip body 251. The other end is hinged to the clip body 251, 254, respectively.

4B, when the position recognizing apparatus 20 is mounted on the thin notebook 2, the roller 254 is retracted a lot due to the elastic force of the elastic providing means 255, and the clip body 251 The roller 254 is less retracted as shown in FIG. 4A, and when the clip body 251 is mounted on the position recognition device 20 ). The support bar 256 of the clip portion 25 and the lower surface of the position recognizing device 20 are always horizontally moved by the vertical bar 253 inserted in the vertical groove 27, Lt; / RTI > Therefore, there is little possibility that the position recognition apparatus 20 is tripped in the process of fixing the position recognition apparatus 20 to the notebook using the clip unit 25. [ A sensor (not shown) may be provided on the clip portion 25 to confirm whether the clip portion 25 is properly fitted to the other side of the notebook.

In this embodiment, the camera 22 is mounted on a support post hinged to the body 21. When the position recognition device 20 is mounted on the notebook, the support post 24 is unfolded so that the camera 22 faces the input face which is the upper face of the notebook 1. [ The camera 22 includes optical components such as a charge coupled device (CCD) for converting the reflected light into an electric signal, a light reflected from the input surface, and a lens for transmitting the infrared rays reflected from the pen tip 11 to the CCD . The CCD includes tens to hundreds of thousands of photosensitive elements, and the resolution is determined by the number of photosensitive elements. In the present invention, the higher the resolution of the camera, the better the accuracy of the input system, but a camera having a resolution as low as 640 x 520 can be used. Also, the image sensor of the camera may be CMOS. As the lens of the camera 22, a point symmetrical lens having a constant viewing angle can be used.

In addition, a tilt sensor may be provided around the camera 22 to determine the attitude angle of the camera 22. [

The laser pointer 23 serves to display a reference point on an image obtained by the camera 22. [ In this embodiment, the laser pointer 23 is installed in the support post 24. The laser pointer 23 can be installed at a geometric position where the vibration of the camera is transmitted and the laser can be irradiated to the principal point position of the camera. The reference point may be a center point or a principal point of the image. It is ideal to set the image of the pinhole of the center point of the camera lens so that the image is formed at the center of the CCD. However, considering the difficulty of the installation process, the mark by the laser pointer 23 in the center of the image sensor You might come. If the camera 22 is shaken, the mark of the laser pointer 23 will also be shaken and the mark will be blurred. Further, it may be installed at the first and second reference area positions along the lens of the camera 22. [

Therefore, the controller 30 can easily confirm that the camera 22 is shaken by the shape and size of the mark of the laser pointer 23, so that the captured image can be selected.

Further, it can be seen that the position of the reference point of the laser pointer is changed each time the position recognition apparatus is clipped to the same fixed object, and the position coordinates of the reference point of the actual laser pointer repeatedly clipped to the same fixed object as the reference point of the laser pointer, The difference can be seen. This makes it possible to correct the position coordinates of the fixed object.

5 is a block diagram of the controller shown in FIG. 5, the controller 30 includes a reference image storage unit 31, a camera image receiving unit 38, a first determination unit 32, an image verification unit 33, a second determination unit 40, A template generating unit 41, a matching unit 42, an image correcting unit 34, a position coordinate extracting unit 35, a relative coordinate receiving unit 39, an absolute coordinate calculating unit 36 and an absolute coordinate transmitting unit 37, .

The reference image storage unit 31 stores a reference image that can be compared with an image obtained when a fixed object is photographed using the camera 22 installed in the position recognition apparatus 20. [ The reference image is an ideal fixed subject image that can be obtained when a fixed subject is photographed using a camera installed in the position recognition device 20. [ That is, the image is obtained when the position recognition apparatus 20 is perfectly installed in a fixed position of the fixed subject. The reference image can be created by actually shooting the camera in an ideal environment, but it can also be created by inputting data into the image program. Depending on the installation position of the camera 22, perspective and radial distortion may occur in the reference image 5 of the fixed object, as shown in Fig.

In the reference image 5, a first reference area 6 and a second reference area 7 are displayed. The reference image of FIG. 6 is an example, and the reference image may be different according to the position, the posture, and the viewing angle of the camera in the position recognition apparatus, and the shapes and sizes of the first reference region and the second reference region may be different. The first reference area 6 may be a trapezoidal area for confirming whether the entire input surface of the fixed object belongs to the field of view (FOV) of the camera 22. [ This is to prevent a part of the input surface of the fixed object from being out of the FOV and being unable to be photographed unless the position recognizing device 20 is biased to the right or left or fully inserted.

The second reference region 7 may be a region such as a circle or a rectangle. In the embodiment shown in FIG. 3, the second reference area 7 can not accurately distinguish the fixed object from the background through the image processing algorithm due to the environment and illumination of the space in which the fixed object is located, Is used to calculate the coordinate values of the corners when it is not recognized in the photographed image. The second reference area 7 indicates the maximum area in which it is possible to calculate the coordinate values of the corners in this way. When the reference point by the laser pointer 23 deviates from the second reference area 7, the error between the calculated corner coordinate value and the actual corner coordinate value is out of the allowable range.

The camera image receiving unit 38 receives the image photographed by the camera 22. [ The photographed image 8 is the actual image of the fixed subject irradiated with the laser pointer. In the ideal case, if the photographed image 8 and the reference image 5 coincide with each other but an error occurs in the process of installing the position recognizing apparatus 20, as shown in Fig. 7, (5) do not match. 7 is an explanatory diagram. The shape of the photographed image 8 can be changed according to the position and the installation angle of the camera 22 of the position recognizing device 8. As shown in Fig.

The first judging unit 32 compares the photographed image 8 received by the camera image receiving unit 38 with the reference image 5 so that the reference point 9 of the photographed image 8 becomes the first reference region 6, . The first judging unit 32 judges whether the reference point 9 of the photographed image 8 after the two images are superimposed so that the origin of the reference image 5 and the reference point 9 coincide with the origin of the displayed transparent photographed image 8 It is judged whether it belongs to the first reference region 6 or not. If the reference point 9 is out of the first reference area 6, a part of the input surface of the fixed object deviates from the FOV of the camera 22, And the display light emitting diode 26 provided in the display device. The display light emitting diode 26 is turned off when the user appropriately adjusts the position of the position recognition device 20 so that the reference point 9 comes into the first reference area 6. [

The image verification unit 33 may determine whether the fixed object and background are distinguished in the photographed image 8 by calculating a threshold value of the image by a histogram method through image binarization as one of image processing algorithms. If the fixed subject and the background are distinguished, the photographed image can be directly transmitted to the image correction unit 34. [

If the fixed object and the background are not distinguished by the image processing algorithm, the second determination unit 40 determines whether the reference point 9 of the captured image 8 is included in the second reference region 7. If the reference point 9 deviates from the second reference region 7, the second determination unit 40 informs the user through the display light emitting diode 26 and the like provided in the position recognition apparatus 20 . That is, if the fixed object and the background are not distinguished by the image processing algorithm, even if the reference point 9 of the captured image 8 is within the first reference area 6, if it is outside the second reference area 7, The coordinates of the vertexes of the fixed object can not be obtained in the embodiment shown in FIG. 6, so that the user can be notified via the light emitting diode of the position recognizing apparatus 20 to adjust the coordinates.

The template generating unit 41 generates a template based on the pixel coordinates of the camera, the length of the quadrangle of the fixed object and the camera capturing angle based on the offset between the center of the second reference area 7 and the reference point 9 of the captured image 8 It is possible to generate the fixed subject template T as shown in FIG. 8 by utilizing the image geometric method of the pin hole. A fixed subject template is an image created using data of four vertices of a fixed subject calculated by an image geometric method. In addition, the second reference area 7 is previously divided into a plurality of small areas based on the virtual lattice lines to which the elements of the image reduction ratio are applied, the fixed subject templates corresponding to the respective small areas are stored in advance, You can also use the loading method.

The matching unit 42 compares the center coordinates of the image of the fixed subject template T generated by the template generating unit 41 and the center coordinates 9 of the shot image 8 with the template T image and the shot image 8 ) Can be superimposed to generate a matched image, as shown in Fig. In addition, the registration image may be a registration of the image of the pen tip 11 on the template image T.

The image correcting unit 34 may include an image filter unit to filter the shot image to calculate precise and fine positional coordinates. The image filter unit can confirm the change of the reference point mark by the laser pointer 23 due to the vibration of the camera 22. [ The image filter unit can check the mark by the laser pointer 23 every time the photographed image is photographed so that the image of the mark is blurred and the interference and noise of the image can be blocked by excluding the photographed image when the size is changed.

In the embodiment shown in Fig. 3, the image correcting unit 34 performs a homography transform of the photographed image or the matched image to obtain the corrected image A in which the perspective distortion disappears, as shown in Fig. At least four matching pairs are required to know the parameter values of the homography matrix. (X ₀ , y ₀ ), (x ₁ , y ₁ ), (x ₂ , y ₂ ) of the four corners of the fixed object are extracted by the feature extraction method of Accelerated Segment Test (FAST) ), (x ₃ , y ₃ ). Since the coordinate values (u ₀ , v ₀ ), (u ₁ , v ₁ ), (u ₂ , v ₂ ), and (u ₃ , v ₃ ) of the four corners of the corrected image are already known from the fixed object size, The correction image can be obtained through homography transformation. In the case of using the matching image, the template generating unit 41 utilizes the pixel coordinates of the four vertexes calculated in the process of generating the template.

The position coordinate extraction unit 35 may extract the position coordinates u _t and v _t of the pen tip 11 as a moving subject using the image obtained by the image correction unit 34, The correction coordinate value may be accumulated in the position coordinates of the pen tip 11 in the coordinate correction unit 34. [

The relative coordinate receiving unit 39 receives the relative coordinate information of the moving subject. In the embodiment shown in FIG. 1, the movement trajectory information of the electronic pen 10 corresponds to the relative coordinate information.

The absolute coordinate calculation unit 36 calculates the absolute coordinates of the current pen tip by summing the position coordinates extracted by the position coordinate extraction unit 35 and the relative coordinates received from the relative coordinate reception unit 39. The position coordinate extraction unit 35 intermittently extracts position coordinates using an image, and the absolute coordinate calculation unit 36 calculates absolute coordinates by adding relative coordinates to the extracted position coordinates. When the new absolute coordinates are extracted, the absolute coordinates are again calculated based on the newly extracted absolute coordinates. For example, when the electronic pen 10 is switched from the off state to the on state, the position coordinate extraction section 35 extracts the position coordinates. When the electronic pen 10 is kept in the on state, And the position coordinate extraction unit 35 can extract the position coordinates when the electronic pen is turned on again after the electronic pen is turned off again. Alternatively, the position coordinates may be periodically extracted and compared with the absolute coordinates of the pen tip 11.

The absolute coordinate transmitter 37 transmits absolute coordinates to a terminal such as a smart phone or a computer. The terminal displays the trajectory of the moving subject through the display.

If precise input is not required, the position coordinate extraction section 35 may extract the position coordinates in a short cycle, and transmit the extracted position coordinates directly through the absolute coordinate transmission section 37. [ In this case, the state coordinate receiver 39 and the absolute coordinate calculator 36 are not necessary. For example, when a finger other than the electronic pen 10 is used as a moving subject, relative coordinates can not be measured and precise input is difficult. Therefore, as indicated by a dotted line in FIG. 5, The absolute coordinates can be transmitted to the absolute coordinate transmitter 37 directly.

As the hardware constituting the controller 30, a microprocessor and a memory of the position recognition apparatus 20 can be used.

11 is a conceptual diagram of another example of the position recognition device.

As shown in FIG. 11, the position recognition apparatus 120 may include a first camera 122a and a second camera 122b installed at regular intervals in the main body 121. The first camera 122a and the second camera 122b may be separately installed. The main body 121 may also be provided with a display 129 for displaying the size and type of the fixed object and displaying the system alarm. In the present embodiment, since two cameras 122a and 122b are used unlike the embodiment shown in FIG. 3, the position coordinates of the moving object are obtained by the position coordinate extracting unit 35 of the controller 30 in an image geometric manner Can be calculated. Therefore, unlike the embodiment shown in Fig. 3, this embodiment does not need to calculate the coordinates of the corners of the fixed object. The present embodiment differs from the embodiment shown in FIG. 3 in that it does not need to calculate the coordinates of the vertex of the fixed object, and therefore transfers the photographed image directly to the image corrector 34. FIG.

In the present embodiment, unlike the embodiment shown in Fig. 3, when the laser point 123 of the position recognition apparatus 120 is in the region within the second reference region 7, which is a mark formed by irradiating the fixed object surface, It is possible to determine that the position coordinates of the entire fixed object input surface can be calculated using the cameras 122a and 122b of the fixed object 120. When the reference point by the laser pointer 123 is out of the second reference area 7, It can be regarded that a part of the position coordinates of the input surface of the input surface can not be calculated accurately.

Further, in the present embodiment, the position coordinate correction of the moving subject can be determined by the first camera 122a adjacent to the vertex of the fixed subject. The zero point coordinates or the position angle of the first camera 122a may be calculated by calculation of the image geometric method using the captured image 8. [ Then, the deviation of the calculated zero point coordinate and the zero point coordinate of the reference image (5) can be obtained. The positional coordinates of the moving subject can be corrected using this deviation.

In addition, the deviation of the point indicated on the fixed subject is determined by the reference point in the reference image 5, which is the reference point in a state where the position recognizing apparatus 120 is ideally provided on the fixed object, and the laser pointer, You may. Since this deviation is a value indicating the degree of movement of the position recognition apparatus 120 from the ideal position, the positional coordinates of the moving subject can be corrected using this value.

By repeating the installation of the position recognizing apparatus 120 on the fixed subject, the position coordinate value of the moving subject will be changed by changing the position of the position recognizing apparatus 120. [ Accordingly, by applying the deviation to the position coordinates of the moving subject, the position coordinates of the corrected moving subject may be obtained. Therefore, even if the position of the position recognition apparatus 120 is changed, the positional coordinates of the moving subject can be accurately calculated.

The position recognition apparatus 120 can also be used for electronic documenting an existing paper document having a preprinted area and a handwritten area. These documents are completed by writing the necessary contents directly in the manual area. Such documents include, for example, various contracts, questionnaires, hospital admission / inspection records, resumes, and study materials.

If the reference image of the document is stored in the position recognition apparatus 120, the position recognition apparatus 120 is fixed to the fixed subject (paper document), and then handwritten in the handwriting area of the paper document with the electronic pen 10 , It is possible to obtain an electronic document in which characters, signs, pictures, etc. are inserted in the handwriting area by the above-described method.

If there is no stored reference image, a document is downloaded through the information device connected to the position recognition device 120 or the position recognition device 120, or a document is captured by the camera of the information device, 120). The information device includes a mobile device such as a smart phone and a tablet, and a notebook computer. Down or captured document image on the mobile screen and find the pixel coordinates of the four vertexes of the document displayed on the screen using the electronic pen 10 or an image program. Then, the reference image is generated by using the coordinate value of the vertex and the document image file downloaded or captured, and then transmitted to the position recognition apparatus 120. The transmitted reference image is stored in the reference image storage unit 31. [ In the reference image, an image of a preprinted area of the document and a first reference area and a second reference area may be displayed.

In addition, the first reference area and the second reference area of the stored reference image of the same size can be overlapped with the downloaded or captured document image.

After the generated reference image is stored, a paper document, that is, a fixed subject is fixed to the position recognition apparatus 120, and a paper document is handwritten, an electronic document in which texts, signs, and pictures are inserted in the handwriting area can be obtained.

 The information device can create an image file by transferring the image captured by the camera to a computer.

Fig. 12 is an example of application of a position recognition device to a large display, and Fig. 13 is a conceptual diagram of the position recognition device shown in Fig.

As shown in FIG. 12, the first camera 222a and the second camera 222b of the position recognition device 220 may be separately installed. The first camera 222a and the second camera 222b are installed on a bracket 221 which is a main body and the first camera 222a and the second camera 222b are rotated by the rotation dial 229 of the bracket 221, And the zero point (posture) In addition, a cavity structure may be formed in the lower part of the bracket 221 such that the first camera 222a and the second camera 222b are installed horizontally with one side of the fixed subject.

The position coordinates of the moving object can be calculated by the position coordinate extracting unit 35 of the controller 30 in the image geometry method. That is, a length L between the first camera 122a and the second camera 122b and a straight line connecting the center of the first camera 122a and the moving subject are detected by the first camera 122a and the second camera 122b, And the straight line connecting the center of the second camera 122b with the moving subject connects the center of the first camera 122a and the center of the second camera 122b The positional coordinates of the moving object on the fixed object input surface can be calculated using the angle? With the straight line.

A point-symmetric lens can be used as the lenses of the first camera 222a and the second camera 222b.

In addition, when a plurality of people write, a plurality of electronic pens 210 can be used. Therefore, in this embodiment, the unique code number of the electronic pen 210 is stored in the memory, and the electronic pen 210 generates an image corresponding to the unique code number using the infrared pointer, Can be calculated.

The plurality of electronic pens 210 are managed together with the trajectory coordinates and the individual unique codes in the controller by transmitting the individual unique code number and the position coordinates in one frame data structure in the position recognition device 220, Alternatively, a unique code number can be assigned to each process.

In addition, the handwriting information by the electronic pen 10 can be displayed on the large display or the electronic whiteboard as shown in FIG. 12 through the position recognition device 120. FIG. At this time, by assigning individual unique code numbers to the position recognition apparatus 120, the signboards displayed on the display device can be processed separately or individually by managing the signboards together with the colors of the signboards by the respective unique codes.

In addition, a program of a device such as the position recognition device 220 or a smart phone may receive a unique code number of a moving subject or may generate a unique code number. The contents inputted by the position recognizing apparatus 220 and the moving subject can be confirmed by group and / or individually by using a unique code number, so that the inputted contents can be partially deleted or the color can be changed or modified.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention as defined in the appended claims. You will understand.

The microprocessor and the memory of the mouse module 13 in the electronic pen 10 may be used as the hardware of the controller 30 . Also, the controller 30 may use a controller such as a portable terminal such as a computer, a smart phone, or a smart pad.

Also, a prism and a laser pointer may be installed in a camera of a device having a camera, such as a smart phone, a tablet, or a notebook, without using a separate position recognition device.

In addition, even if there is no laser pointer, the camera can create a virtual pointer at the center of the captured image, that is, the main point, and set the reference point. The virtual pointer can not remove the captured image due to camera shake, but it will serve as a reference point by the laser pointer 23.

Further, when the display is used as a fixed subject, the reference point of the reference image may be displayed directly on the display.

In addition, the user can use the infrared pointer 13 of the electronic pen to mark the edges of the fixed object input surface by using the first determination unit 32 to check whether or not the edges come in the shot image.

In addition, the controller 30 may be incorporated in the position recognition apparatus 20. [

In addition, the first reference area and the second reference area displayed in the reference image may be represented by imaginary lines.

10: electronic pen 11: pen tip
13: Mouse module 14: Infrared pointer
20: position recognition device 22: camera
23: laser pointer 25: clip portion
26: light emitting diode 30: controller

Claims (13)

A handwriting input device for inputting handwriting by a moving subject on an input surface of various fixed objects,
And a camera for photographing the moving object and the input surface at the same time to obtain a photographing image having a reference point, the position recognizing device being detachably installed in the stationary subject,
When the entire input surface of the article enters the field of view (FOV) of the camera, the first reference area, which is the area where the reference point of the captured image can be placed, and the second reference area, A first determination unit for comparing the reference image and the captured image to determine whether the reference point is located within the first reference region, And a second determiner for determining whether the reference point is located within the first image pickup unit, and calculating a position coordinate of the moving object using the image pickup image,
The controller calculates the positional coordinates of the moving subject only when the second determination unit determines that the reference point of the captured image is located within the second reference area when the edge of the fixed subject is not recognized in the captured image And a second input device. The method according to claim 1,
And a pointer for irradiating light toward the input surface,
Wherein the reference point is a mark formed on the input surface by a pointer. The method according to claim 1,
Wherein the reference point is a principal point of the photographed image. The method according to claim 1,
And a template generator for obtaining a coordinate value of four vertexes of the input surface of the fixed object using the deviation between the ideal reference point and a reference point of the captured image to form a fixed subject template. The method according to claim 1,
Wherein the moving subject is an electronic pen having a pen tip that moves on an input surface of the fixed subject and acquires relative coordinate information of a movement trajectory of the pen tip. 6. The method of claim 5,
Wherein the electronic pen further comprises an infrared pointer for illuminating the pen tip with light. The method according to claim 1,
The controller comprising:
An image checking unit for checking whether four corners of the fixed object are recognized in the captured image;
An image corrector for correcting the perspective distortion of the photographed image to generate a corrected image;
And a position coordinate extracting unit for extracting a position coordinate of the moving subject in the corrected image. 6. The method of claim 5,
The controller comprising:
An image checking unit for checking whether four corners of the fixed object are recognized in the captured image;
An image corrector for correcting the perspective distortion of the photographed image to generate a corrected image;
A position coordinate extracting unit for extracting a position coordinate of the moving subject in the corrected image;
And an absolute coordinate calculation unit for calculating absolute coordinates of the pen tip using the position coordinates obtained by the position coordinate extraction unit and the relative coordinate information of the moving subject. The method according to claim 1,
The position recognition device includes:
A clip body,
A support bar extending from the clip body and contacting the lower surface of the fixed object,
A vertical bar extending from the clip body and inserted in a vertical groove formed in the position recognizing device to guide the vertical movement of the clip body,
A roller inserted in a guide groove elongated in the position recognizing device,
Elasticity providing means connected to the roller to provide an elastic force to the roller in a direction in which the roller is away from the clip body,
Further comprising a clip portion including a connecting bar, one end of which is hinged to the clip body, and the other end of which is hinged to the roller. The method according to claim 1,
Wherein the position recognition device includes a first camera and a second camera,
And the lenses of the first camera and the second camera are point-symmetrical lenses. 3. The method of claim 2,
Wherein the position recognition device includes a first camera and a second camera,
Wherein the controller corrects the positional coordinates of the fixed subject based on the deviation of the mark displayed on the fixed subject by the reference point and the laser pointer in the reference image. The method according to claim 1,
A plurality of position recognition devices,
Wherein a program is provided in the device connected to the position recognition device or the position recognition device to distinguish input information according to each unique code number of the plurality of position recognition devices. The method according to claim 1,
Wherein the position recognition device uses a reference image generated by processing an image of a fixed subject that is downloaded or captured using an information device connected to the position recognition device.

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