KR101766447B1 - Optics sheet having dot pattern for writing with electronic pen and smart electric board - Google Patents

Abstract

The present invention relates to a multi-layer optical sheet having a dot pattern for electronic pen writing, the multi-layer optical sheet which is formed to have a multi-layer, is attached on a front side of an image apparatus or a board, can track a trajectory of electronic pen writing, and displays the writing while recognizing the writing. The multi-layer optical sheet comprises: a pattern having a fine pattern comprising dots which are formed at intervals on intersection points of a virtual grid and have encoded location information to determine location information of an electronic pen; a diffusion film which is formed on a front side of the pattern film and blocks and diffuses a portion of light emitted by the image apparatus; a protection film which is formed on a front side of the diffusion film, is made of PET or polycarbonate, and is treated with anti-glare coating; a blocking film which is formed on a rear side of the pattern film and reflects and blocks a portion of the light emitted by the image apparatus; and an adhesive layer which is formed on a rear side of the blocking film and is attached on a front side of the image apparatus or the board.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a multi-layer optical sheet for writing electronic pens and a smart electronic board having a dot pattern,

The present invention relates to an optical sheet and an electronic board including the same, and more particularly, to a multi-layer optical sheet for electronic pen-pliers capable of determining position information of an electronic pen written on a surface of a dot pattern having positional information, The present invention relates to a smart electronic blackboard.

In general, the electronic pen can recognize the trajectory of a place where a dot pattern is formed and can be handwritten. When the electronic pen is connected to an electronic note, a notebook, a smart phone, a smart TV, It can be checked immediately, and the created and edited contents can be stored in internal memory or shared with other users or devices via e-mail, SNS, cloud, etc.

In the electronic pen recognition, there is a touch screen type or a method using an external sensing sensor. The larger the size of the display screen, the higher the manufacturing cost, the higher the power consumption, and the lower the recognition rate. Accordingly, a technology has been developed in which an encoding pattern including positional information is finely formed on a display screen or a film, and a relative position or an absolute position of the electronic pen to be written on the surface is determined.

In the prior art related thereto, Patent Document 1 discloses an electronic pen which is used on an encoded paper for optical reading which operates on an absolute position coding pattern and is equipped with a pattern coding in which a plurality of marks are formed so that each represents a nominal position and determines a position The paper is open.

However, when using an electronic pen, the paper of Patent Document 1 has a problem that when the electronic pen is used on a glossy surface such as a coated paper or a white board, or on a light-emitting surface such as a liquid crystal screen, It is difficult to precisely discriminate the position of the object, and thus there arises a problem in positioning and decoding. However, there is a problem that when the paper is made opaque, the background or the display screen is not clearly visible.

International Publication No. WO 01/26032 (published April 12, 2001)

SUMMARY OF THE INVENTION The present invention has been conceived to solve all the problems described above, and it is an object of the present invention to provide an electronic pen, An object of the present invention is to provide a multilayer optical sheet for writing electronic pens having a dot pattern capable of positioning, visibility and sharpness of a display screen being increased,

In addition, the optical sheet can be attached to the front surface and the electronic pen can be used. By selectively implementing the transparent and opaque display, it is possible to switch the display device to the more blackboard, to use it quickly and conveniently, It is possible to proceed smoothly without interruption, and it is possible not only to be able to write during the course of lecture or presentation, but also to eliminate irregular reflection, increase the visibility and clarity of the projected image in the edition, The purpose of the present invention is also to provide a smart blackboard which is transparent and opaque.

In addition, since an infrared ray detection sensor or a touch panel for detecting the writing means applied to the conventional electronic board is unnecessary, it can be applied to a large-sized video apparatus or an electronic board. It has its purpose.

According to an aspect of the present invention, there is provided an electronic pen having a multi-layered structure and having a dot pattern to be attached to a front side of a video apparatus or blackboard and capable of tracking an electronic pen writing trace, 1. A multi-layer optical writing writing sheet comprising: a pattern film formed with a gap at an intersection of virtual lattice lines and having a fine pattern formed of dots whose positional information is encrypted so as to determine positional information of the electronic pen at the time of writing; A diffusion film formed in front of the pattern film and intercepting and diffusing a part of light emitted from the video apparatus; A protective film formed on the front side of the diffusion film and made of PET or polycarbonate and treated with an anti glare coating; A blocking film formed behind the pattern film and reflecting and blocking a part of light emitted from the video apparatus; And a dot pattern formed on the back of the blocking film and adhered to an entire surface of a display device or blackboard.

The diffusion film of the present invention may further comprise: an antiglare-coated PET layer; A diffusion layer formed in front of the PET layer and having a plurality of round grooves formed on a front surface thereof, a light diffusing agent distributed therein to diffuse light forward, and a light absorbing agent applied to the round grooves; And an adhesive layer formed behind the PET layer.

Also, in the present invention, the diffusion film may be formed on the rear surface of the pattern film.

At this time, an insert film formed of PET or polycarbonate and coated with an anti-glare coating may be formed between the diffusion film formed on the rear surface of the pattern film and the barrier film.

In addition, the barrier film of the present invention comprises a substrate layer formed on one surface so as to have a plurality of irregularities so as to uniformly disperse the reflected light and increase reflectance; An AL evaporation layer deposited on one surface of the substrate layer to reflect a part of light; A transparent transparent layer formed on one side of the AL deposition layer to transmit light; A protective layer coated on one side of the transmissive layer; And an electromagnetic wave blocking layer formed on the opposite surface of the base layer to block electromagnetic waves, wherein the electromagnetic wave blocking layer comprises a base layer in which one or more fine metal particles selected from copper, silver, and nickel are uniformly dispersed in a transparent synthetic resin, An indium-tin oxide layer deposited on the zirconium oxide layer; and a layer of indium-tin oxide deposited on the indium-tin oxide layer, wherein the indium- And a silicon dioxide layer.

Further, in the adhesive layer of the present invention, fine metal particle fillers made of copper or silver can be uniformly dispersed in a transparent binder.

Further, in the present invention, a transparent light-transmitting plate is formed between the pattern film and the barrier film, and the light-transmitting plate may be formed of any one selected from an acrylic plate, a polycarbonate plate and a glass plate.

The present invention also provides a frame structure comprising a plurality of unit frames connected to each other; A video device having a flat or curved display panel installed at an inner rear side of the frame frame and outputting an image; (PDLC), which is coupled to the inside of the frame frame and covers the front of the video equipment and is transparent or opaque according to supply and interruption of power supply, and is made of polymer dispersed liquid crystal (PDLC) A variable panel portion including a scattered PDLC layer, an ITO layer formed on the front and rear surfaces of the PDLC layer and coated with indium-tin oxide, and a substrate layer formed on an outer surface of each ITO layer; A PMMA sheet having a plate surface joined to a substrate layer formed in front of the variable panel portion and made of a plate; A light guide plate attached to a rear surface of the variable panel unit and having a dimming function and provided with a dimming function and diffusing light emitted from the LED light source when power is applied to increase the sharpness of letters written; A reflective film attached to a rear surface of the light guide plate and deposited on aluminum to reflect a part of the light to prevent the screen of the video device from being visibly turned off; Control means for controlling the brightness of the LED light source and having a power supply unit for supplying power; And a multi-layer optical sheet attached to a front surface of the PMMA sheet and having a dot pattern for allowing the trace of an electronic pen writing trace to be tracked so as to be displayed on a screen while recognizing handwriting, wherein the optical sheet is provided at an intersection of virtual grid lines A pattern film formed on the front side of the pattern film and having a minute pattern formed of dots formed with dots whose positional information is encrypted so that positional information of the electronic pen can be determined at the time of writing; A protection film formed on the front side of the diffusion film and made of PET or polycarbonate and subjected to anti glare coating; and a protective film formed on the rear side of the pattern film, A blocking film for reflecting and blocking a part of the light, and an adhesive layer formed on the back of the blocking film, .

The present invention also provides a frame structure comprising a plurality of unit frames connected to each other; A video device having a flat or curved display panel installed at an inner rear side of the frame frame and outputting an image; (PDLC), which is coupled to the inside of the frame frame and covers the front of the video equipment and is transparent or opaque according to supply and interruption of power supply, and is made of polymer dispersed liquid crystal (PDLC) A variable panel portion including a scattered PDLC layer, an ITO layer formed on the front and rear surfaces of the PDLC layer and coated with indium-tin oxide, and a substrate layer formed on an outer surface of each ITO layer; A PMMA sheet having a plate surface joined to a substrate layer formed in front of the variable panel portion and made of a plate; A light guide plate attached to a rear surface of the variable panel unit and having a dimming function and provided with a dimming function and diffusing light emitted from the LED light source when power is applied to increase the sharpness of letters written; A tempered glass provided between the light guide plate and the video apparatus; A reflection film attached to the rear surface of the tempered glass and deposited on aluminum to reflect a part of the light to prevent the screen of the video equipment turned off from being visible; Control means for controlling the brightness of the LED light source and having a power supply unit for supplying power; And a multi-layer optical sheet attached to a front surface of the PMMA sheet and having a dot pattern for allowing the trace of an electronic pen writing trace to be tracked so as to be displayed on a screen while recognizing handwriting, wherein the optical sheet is provided at an intersection of virtual grid lines A pattern film formed on the front side of the pattern film and having a minute pattern formed of dots formed with dots whose positional information is encrypted so that positional information of the electronic pen can be determined at the time of writing; A protection film formed on the front side of the diffusion film and made of PET or polycarbonate and subjected to anti glare coating; and a protective film formed on the rear side of the pattern film, A blocking film for reflecting and blocking a part of the light, and an adhesive layer formed on the back of the blocking film, .

According to the present invention, since the recognition rate of the electronic pen is greatly increased by being attached to a video apparatus and a blackboard on which the electronic pen is used, it is possible to accurately determine and position the dot pattern of the dot pattern by the electronic pen, And when rolled into a sheet form, it is possible to roll, which makes it easy to store and move.

In addition, the optical sheet can be attached to the front surface and the electronic pen can be used. By selectively implementing the transparent and opaque display, it is possible to switch the display device to the more blackboard, to use it quickly and conveniently, It is possible to proceed smoothly without interruption, and it is possible not only to be able to write during the course of lecture or presentation, but also to eliminate irregular reflection, increase the visibility and clarity of the projected image in the edition, It is effective.

In addition, since it does not require an infrared sensor or a touch panel for detecting the writing means applied to the existing electronic board, it can be applied to a large-sized video apparatus or an electronic board. .

1A and 1B are exploded perspective views of an optical sheet according to an embodiment of the present invention.
2 is a cross-sectional view of an optical sheet according to an embodiment of the present invention.
3A and 3B are enlarged views of imaginary grid lines, intersections, and dots of a pattern film according to an embodiment of the present invention.
FIG. 4A is a perspective view illustrating an electronic pen used in a planner of an optical sheet according to an embodiment of the present invention, and FIG. 4B is an explanatory diagram of an electronic pen used in an enlarged size of the optical sheet.
5 is a view of a diffusion film according to an embodiment of the present invention.
6A is a sectional view of a barrier film according to an embodiment of the present invention, FIG. 6B is a cross-sectional view of a barrier film according to an embodiment of the present invention, FIG. 6C is a detailed sectional view of a portion A of FIG. FIG. 6D is a detailed view according to another embodiment of part A of FIG. 6B, and FIG. 6E is an electron microscope photograph of the metal material of FIG. 6D.
FIG. 7A is an exploded perspective view illustrating a smart electronic whiteboard according to an embodiment of the present invention, and FIG. 7B is a sectional view of a smart electronic whiteboard according to an embodiment of the present invention.
8A is an exploded perspective view illustrating a smart electronic blackboard according to another embodiment of the present invention, and FIG. 8B is a sectional view of a smart electronic blackboard according to another embodiment of the present invention.
FIG. 9 is a view illustrating an operation of varying the transparent and opaque state of the smart electronic whiteboard according to an embodiment of the present invention.
FIG. 10A is a view showing a black screen when power is turned off in a video camera in the absence of a reflective film in the present invention, and FIG. 10B is a view showing a black screen invisible when a reflective film is attached in the present invention.
FIG. 11A illustrates an electronic writing mode of a smart electronic whiteboard according to an exemplary embodiment of the present invention, and FIG. 11B illustrates a general electronic writing mode of a smart electronic whiteboard according to an exemplary embodiment of the present invention.

Best Mode for Carrying Out the Invention Reference will now be made in detail to the preferred embodiments of the present invention with reference to the accompanying drawings, in which a multilayer optical sheet for writing an electronic pen having a dot pattern according to the present invention and a smart electronic whiteboard are described.

The multilayer optical sheet 1 for writing electronic pens having a dot pattern according to the present invention has a multilayer structure and is attached to the entire surface of a display device such as a monitor, a notebook computer, and a liquid crystal TV, or a blackboard, 1A and 2B, the pattern film 10, the diffusion film 20, and the like are formed on the surface of the screen, ), A protective film (30), a barrier film (40) and an adhesive layer (50).

3A, the pattern film 10 has dot dots 13 formed at predetermined intervals from the intersection 12 where the imaginary grid lines 11 cross each other, May include at least two or more different numbers of combinations and have fine pattern information in which the position information is encrypted so as to determine positional information of the electronic pen P at the time of writing.

The dot 13 may be formed of an infrared absorbing ink made of a phthalocyanine compound, a naphthalocyanine compound, an aminium compound, or the like, and each dot 13 may have a crossing point 12 of an imaginary lattice line 11, The position information can be provided by the coordinate value of the pattern determined according to the position formed around the center of the screen.

For example, referring to FIG. 3B, the dot 13 may exist at four positions according to the relationship with the intersection 12 of the imaginary grid line 11, and the dot 13a may exist at the right side of the intersection 12 The dot value is set to "1" when the dot 13b is located above the intersection 12, the dot value is set to "2" when the dot 13c is located to the left of the intersection 12, The dot value is set to "3" and the dot value is set to "4" when the dot 13d is positioned below the intersection point 12, 13) in accordance with the position information.

The dots 13 may be formed in a diagonal direction not on the imaginary grid line 11 and a plurality of dots 13 may be formed on the intersection 12 of one imaginary grid line 11, In this case, each dot value can be expressed in arbitrary coordinates in a manner of being divided into an x coordinate and a y coordinate, and position information can be provided from these coordinate values.

The imaginary grid lines 11 may be formed horizontally and vertically along a predetermined interval and the distance between the grid lines 11 may be formed to be 250 to 300 탆 and the dots 13 may be formed by imaginary grid lines 11 And the dot 13 may be formed at a position at a distance of 1/8 to 1/4 around the intersection 12 of the imaginary grid line 11 and the dot 13 may be formed at the intersection 12 of the imaginary grid line 11, The dots may be formed in association with each other and have a diameter in the range of 50 to 100 mu m.

4A, the electronic pen P includes a pen tip P1 formed at one end thereof in the form of a pen tip of synthetic resin or silicon and protruding outward to form a pen on the surface of the optical sheet 1, (P1) is detachably attached to the pen tip (P1), and after the pen tip (P1) is detached, a ballpoint pen with ink stored therein can be mounted to be able to be written on paper or the like.

Referring to FIG. 4B, the electronic pen P includes a light source P2 and a sensor P3. The light source P2 emits infrared light and emits the infrared light to the outside. The sensor P3 senses infrared rays scattered at a portion where the dot 13 of the pattern film 10 is not formed as an infrared sensor, The position information can be calculated by calculating the absolute coordinate values by continuously sensing the pattern information of the dots 13. [ For example, when 36 dots (13) are recognized by 6 horizontal and vertical six grid lines (11) on a 6x6 grid, the position information according to each dot value is calculated, The coordinate values can be grasped.

A power switch P4 and a charging terminal (not shown) are formed at the other end of the electronic pen P. A wireless communication module (not shown) and a rechargeable battery (not shown) capable of short-distance wireless communication such as wifi and Bluetooth are built in the electronic pen P and a status indicator P5 is formed in the middle. Accordingly, the coordinate values sensed and calculated by the sensor P3 are analyzed by a control unit provided in the electronic pen P itself, and then transmitted to an external device via a wireless communication module and displayed on a display screen, A coordinate value is analyzed by a processor of an external device, and then an actual coordinate value at which the electronic pen P is located is calculated and displayed on a display screen .

The diffusion film 20 is made of a transparent material and laminated on the front side of the pattern film 10 to prevent light saturation by absorbing and blocking a part of the light emitted from the imaging device, The accurate position information of the dot pattern can be determined and positioned, and the remaining part of the light is diffused forward, thereby increasing the visibility and sharpness without dimming the image on the display screen or reducing the contrast significantly.

5, the diffusion film 20 is provided with an antiglare-coated PET layer 21 so that light can be transmitted without irregular reflection, so that the screen of the imaging device can be clearly seen, A diffusion layer 22 is formed in front of the diffusion layer 21. The diffusing layer 22 diffuses the light diffusion material 22b in a forward direction to form a plurality of round grooves 22a on the front surface of the diffusion layer 22, (22c) is applied to absorb a part of the light emitted from the image display device to prevent light saturation, to absorb external illumination light to obtain a clear image, and to allow light to pass through the portion where the light absorber (22c) Lt; / RTI > An adhesive layer 23 is formed on the rear side of the PET layer 21 and bonded to the pattern film 10.

When the brightness is high depending on the type of the video apparatus, the optical sheet 1, to which the diffusion film 20 is adhered by the adhesive layer 23, is attached to the rear side of the pattern film 10, , Even when the luminance is high, such as a flat or curved TV with a liquid crystal, the light saturation is prevented, the recognition rate of the electronic pen sensor P3 increases, and accurate position information determination and positioning of the dot pattern can be performed. Referring to FIG. 1B, if an insert film made of PET or polycarbonate and coated with an anti-glare coating is inserted between the diffusion film 20 and the barrier film 40 formed on the rear surface of the pattern film 10, A part of the light transmitted through the film 40 is prevented from being transmitted to the front, so that the recognition rate of the electronic pen can be further increased.

The protective film 30 is formed on the front of the diffusion film and is made of PET or polycarbonate to protect the optical sheet 1. When the protective film 30 is made of PET, it can be rolled as a sheet type, When the thin film is made of a thin plate of carbonate, it is not possible to roll, but it can be bent flexibly, and strength and hardness are increased. Therefore, frequent replacement is not required due to damage of the protective film by the plate, and a translucent plate 60 to be described later is not required. The anti-glare coating solution is coated on the outer surface of the protective film 30 to a thickness of 0.1 to 0.5 mm, so that the light is not diffused and transmitted well, so that the screen of the image display device is more clearly seen. It is possible to write correctly without slipping. In addition, the protective film 30 may be detachably attached to the diffusion film 20 so as to be replaceable.

The blocking film 40 is a kind of reflective film formed on the rear side of the pattern film 10, which is similar to a film protecting privacy, and blocks a part of the light emitted from the video equipment to be transmitted forward . The light transmittance of the blocking film 40 is preferably 65 to 90%, and when the light transmittance is less than 65%, the visibility and brightness of the display screen are reduced to make writing difficult to see. When the light transmittance exceeds 90% Due to the weathering, the recognition rate of the sensor is degraded and the image of the dot pattern is distorted, making it difficult to accurately read the position information.

 As described above, since the blocking film 40 is provided in front of the video apparatus, the reflectance of light incident from the video apparatus is increased, and about 65 to 90% of the light emitted from the video apparatus is transmitted forward, And the recognition rate of the electronic pen is increased, so that accurate position information determination and positioning of the dot pattern by the electronic pen can be performed.

6A and 6B, the blocking film 40 is provided with a base layer 41, and the base layer 41 has a plurality of unevenness 41a formed on one surface thereof, And an AL deposition layer 42 is deposited on one surface of the substrate layer 41 to reflect light and a surface of the AL deposition layer 42 A transparent layer 43 such as polypropylene is formed to transmit light and a protective layer 44 is coated on one surface of the transparent layer 43 to prevent damage to the blocking film 40, The electromagnetic wave shielding layer 45 may be formed on the opposite side of the layer 41 to block electromagnetic waves generated from the imaging device.

In general, the vibration of an electromagnetic wave electromagnetic field propagates to a wavelength, that is, a periodic change of an electric field and a magnetic field is transmitted as a wave, and an electric field and a magnetic field coexist with each other.

Referring to FIG. 6C, the electromagnetic wave shielding layer 45 may include a base layer 45a uniformly dispersing one or more fine metal particles selected from copper, silver, and nickel in a transparent synthetic resin, A transparent board layer 45b having vinyl methyl dichlorosilane coated thereon is formed on the base layer 45a and a plurality of thin films of the metal oxide layer are deposited on the base layer 45a in a multi-layered manner.

That is, a zirconium oxide layer 45c on which zirconium oxide is deposited is formed on the board layer 45b, an indium-tin oxide layer 45d deposited on the zirconium oxide layer 45c is formed, and the indium- By forming the silicon dioxide layer 45e deposited on the oxide layer 45d, the deposition is easy, and the electromagnetic wave shielding effect is increased, so that the transmittance of light can be kept transparent. In addition, since zirconium oxide, indium-tin oxide and silicon dioxide are low in coefficient of thermal expansion, they are resistant to high temperatures and are excellent in heat resistance, so that they are not greatly affected by the heat generation of image display devices and durability of the optical sheet is increased.

6D and 6E, the electromagnetic wave shielding layer 45 is irregularly dispersed in the polyester resin 46 and the polyester resin 46, and a pinhole 47a is formed therein And a plurality of metal oxide films 47b having different types are stacked and laminated.

The metal material 47 is formed by laminating a plurality of metal oxide films 47b selected from zirconium oxide, indium-tin oxide, and silicon dioxide into natural fibers or synthetic fibers having a fine diameter of 2.6 to 5 탆, Followed by heat treatment at a temperature of 650 to 750 ° C in an inert gas atmosphere to selectively remove only natural fibers or synthetic fibers to form a pinhole 47a to form a rod-like hollow fiber capable of absorbing electromagnetic waves do. The diameter of the natural fiber or synthetic fiber of 2.6 to 5 탆 is considered to be light weight and the thickness of the thin film, and the thickness of the metallic material covering 2.6 to 5 탆 takes into account the strength and the shape retention of the rod-like hollow fiber.

At this time, the coating of the metal oxide film 47b is performed by depositing natural fibers or synthetic fibers in the plating solution at a temperature range of 70 to 80 캜 for about 1 hour to have a thickness of 2.6 to 5 탆.

In addition, the heat treatment may be performed by charging a natural material 47 or a metal material 47 coated with a metal oxide film 47b into a heat treatment apparatus, and then heat-treating the material at a temperature ranging from 650 to 750 ° C for 1 to 2 hours, By burning synthetic fibers, the pinholes 47a are formed to produce the metal material 47. [

The electromagnetic wave shielding layer 45 is formed by uniformly dispersing the metal material 47 thus produced in a binder composed of the polyester resin 46 to obtain a high electromagnetic wave shielding ratio.

Accordingly, the blocking film 40 is provided with an AL evaporation layer 42 on the side of the imaging device to reflect part of the light emitted from the imaging device, thereby increasing the recognition rate of the electronic pen and accurately determining the position information of the dot pattern by the electronic pen And an electromagnetic wave shielding layer 45 is provided on the opposite side of the electromagnetic wave shielding layer 45 so that light transmitted through the AL deposition layer 42 is transmitted without being reflected while shielding electromagnetic waves, .

The adhesive layer 50 is formed on the rear side of the barrier film to be attached to the entire surface of the imaging device or blackboard, and the fine metal particle filler made of copper or silver may be uniformly dispersed in the binder made of a transparent synthetic resin. Thus, the electromagnetic wave shielding effect can be further increased by attaching to the screen contacting with the video equipment.

1A, a transparent translucent plate 60 is formed between the pattern film 10 and the barrier film 40 to form a panel-type optical sheet 1, It is possible to protect the screen of the apparatus and enhance the strength thereof, thereby enabling stable writing with the electronic pen P. At this time, the transparent plate 60 may be formed of any one selected from an acrylic plate, a polycarbonate plate, and a glass plate.

As described above, the diffusion film 20 and the blocking film 40 are attached to the front and rear surfaces of the pattern film 10, respectively, to absorb or reflect a part of the light emitted from the imaging device, thereby increasing the recognition rate of the electronic pen At the same time, a part of light is transmitted and diffused, thereby blurring the image of the display screen or increasing the visibility and sharpness without significantly decreasing the contrast.

7A and 7B, the smart electronic whiteboard S according to the first embodiment of the present invention includes a frame 100, an imaging device 200, a variable panel unit 300, a PMMA sheet 400, A light guide plate 500, a reflection film 600, a control means 900, and an optical sheet 1.

The frame frame 100 has a plurality of unit frames 110 connected to form a substantially rectangular frame.

The frame 200 may be mounted on the inner side of the frame 100 and the frame may be coupled to the frame 100 directly or by fixing means. May be coupled to surround the rim of the imaging device 200.

The OLED (Organic Light Emitting Diode) is an OLED (Organic Light Emitting Diode) device having a flat or curved display panel such as an OLED, an LED and an LCD. It is a self-luminous organic material that emits light by itself. It is thinner, thinner, thinner, driven by lower voltage, and has a wide viewing angle and fast response speed. So that it is preferable as a video apparatus of the present invention.

The video device 200 is connected to a computer through a wired or wireless connection so that a video image displayed on the video device is displayed on the screen of the video device so that the video can be displayed in a classroom, Or to present a meeting or presentation. At this time, a speaker K electrically connected to the video equipment 200 may be installed on both sides of the frame 100.

The variable panel unit 300 is coupled to the inside of the frame 100 and is disposed to cover the front of the video apparatus 200. When the power is supplied through the power supply unit, The display of the apparatus 200 can be seen. On the contrary, if the power supply of the power supply unit is turned off, the display panel 200 can be changed to an opaque state.

For this, the variable panel unit 300 includes a PDLC layer 310 formed of polymer dispersed liquid crystal (PDLC) and transmitting or scattering light, a liquid crystal layer 310 formed on the front and rear surfaces of the PDLC layer 310, A transparent ITO layer 320 coated with indium-tin oxide, and a substrate layer 330 formed on the outer surface of each ITO layer 320.

Here, the PDLC layer 310 is a liquid crystal cell used in a liquid crystal display (LCD). The PDLC layer 310 is made of a polymer dispersed liquid crystal, and if the power is not supplied, the liquid crystal molecules become irregular in direction, When the power is supplied, the directions of the liquid crystals are aligned and the refractive indexes of the liquid crystals coincide with each other.

The ITO layer 320 is formed by depositing indium-tin oxide (ITO) on a film such as PET or polyethylene by vacuum evaporation, and is used as a material of a transparent electrode of a thin flat display.

The substrate layer 330 may be made of a thin polyethylene terephthalate (PET) or a glass substrate and protects the inner PDLC layer 310 and the ITO layer 320, To provide strength.

In this case, the PDLC layer 310 is interposed between the two substrate layers 330. At this time, the ITO layer 320, which is a transparent electrode, is formed on the inner surfaces of the two substrate layers 330, A polymer dispersed liquid crystal (PLDC) may be filled between the two ITO layers 320 to form a sealed form, or a film of a polymer dispersed liquid crystal (PLDC) may be inserted and cemented.

In addition, the OCA (Optically Clear Adhesive) film is an optical transparent adhesive film and acts as a tape on both sides. In the variable panel portion 300, an OCA film 340 is interposed and adhered to the PMMA sheet 400 , And an OCA film (340) is interposed between the light guide plate (500) and the light guide plate (500). In this case, the composition for the OCA film 340 may contain 35 to 60% by weight of 2-ethylhexyl acrylate, 25 to 50% by weight of hydroxypropyl acrylate, 1 to 4,4'-dicyclohexylmethane diisocyanate as a curing agent, And 1 to 10% of 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide as a photoinitiator, wherein the 2-ethylhexyl acrylate and the hydroxypropyl acrylate are polymerized to obtain an acrylate polymer And the above-mentioned curing agent and a photoinitiator are mixed and then coated, followed by curing by heating at 70 to 120 ° C.

Also, the PDLC layer 310 may include 10 to 20% by weight of a polyfunctional urethane oligomer, 30 to 50% of tetrahydrofurfuryl methacrylate as a diluent, 10 to 30% of 2-ethylhexyl acrylate as a diluent, 0.1 to 10% of propylene glycol diacrylate, 0.1 to 10% of 1,6-hexanediol diacrylate, and 1 to 10% of 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide as a photoinitiator have.

At this time, the tetrahydrofurfuryl methacrylate and the 2-ethylhexyl acrylate function as a diluent to enhance the adhesion, and the dipropylene glycol diacrylate and the 1,6-hexanediol diacrylate form a polymer , And the diluent and the cross-linking agent preferably have a composition ratio of 100: 1 to 199: 1.

For example, as a diluent, 3.0 kg of tetrahydrofurfuryl methacrylate, 1.7 kg of 2-ethylhexyl acrylate, 0.02 kg of dipropylene glycol diacrylate as crosslinking agent, 0.02 kg of 1,6-hexanediol diacrylate, , And 4,6-trimethylbenzoyl-diphenyl-phosphine oxide were mixed, and then 1.2 kg of the polyfunctional urethane oligomer was added thereto and mixed in a completely homogeneous phase to obtain a polymer dispersed liquid crystal composition. Then, the mixture prepared by mixing the composition with the liquid crystal at a ratio of 3: 7 was coated on the rear ITO film, and the front ITO film was laminated and irradiated with UV light to obtain a polymer dispersed liquid crystal composite.

The thickness of the composite was measured and the T-peel strength was measured. The T-peel strength was measured using a Universal Testing Instrument Model TM instrument and measured on a 200-g load cell. The width of the specimen was 2.54 cm . As a result, it was confirmed that the thickness was 20 占 퐉, the T-peel strength (gm / 2.54 cm) was 230, and the adhesion was very excellent.

Accordingly, when the composition and the composition range and the composition ratio thereof are satisfied, it is possible to realize a PDLC layer having a sufficiently low driving voltage and excellent adhesion between the PDLC layer and the ITO layer, so that the PDLC layer and the ITO layer are not easily peeled or damaged by external impact or physical force will be.

When the power is supplied from the power supply unit to the opposing ITO layer 320, the polymer dispersed liquid crystal in the PDLC layer 310 is arranged to have a certain direction by the electric field, (A transparent mode in Fig. 9 (a)). At this time, the viewing angle is 100 to 160 degrees and the transmittance is 70% or more. On the other hand, when power is not applied, polymer dispersed liquid crystals inside the PDLC layer 310 are randomly arranged randomly, so that incident light is scattered to become opaque (opaque mode of FIG. 9 (b)).

Thus, by selectively implementing the transparent and opaque display modes, it is possible to switch the video apparatus to a general blackboard and use it, and it is possible to switch smoothly and conveniently, smoothly without interruption, It is possible to send e-paper during the presentation, and it is possible to concentrate the contents of the lecture.

The PMMA sheet 400 is coupled to a substrate layer 330 formed in front of the variable panel unit 300 and has a plate writing surface 410 on which a writing plate is formed, The screen of the display device 200 can be seen more clearly and is attached to the substrate layer 330 by the OCA film 340.

PMMA is a polymer material obtained by polymerizing methyl methacrylate (CH ₂ -C (CH ₃ ) COOCH ₃ ) as polymethylmethacrylate, and is usually called acrylic resin. It is transparent and has high light transmittance and hardness It has excellent gloss and light resistance, and is suitable as a plate surface.

The light guide plate 500 is attached to the rear surface of the variable panel unit 300 to protect the video equipment. The light guide plate 500 is provided with an LED light source 510 having a dimming function and made of a transparent material.

The light guide plate 500 is formed by coating a light emitting material pigment and a hard coating pigment on a PMMA material and diffusing and diffusing the light of the LED light source 510 to the front surface when power is applied to increase the writing function, The visibility and sharpness of the lecture can be increased, and the lecture contents can be conveyed more concentratedly. In particular, when the room is dark, for example, the classroom or the inside of the lecture room is kept dark, the classroom is being performed together with the video image of the video device 200, and the LED light source 510 is powered The letters written in the dark room can be clearly seen by the divergence and diffusion of light of the light guide plate 500 and smooth steel can be progressed without interruption in the middle.

At this time, since the LED light source 510 has a dimming function, the dimming control unit of the control unit 900 can adjust the brightness of the light according to the darkness of the room.

In addition, the LED light source 510 may include a plurality of lamp groups (not shown) having the same illumination color so that they have different colors. For example, the lamp groups may be white, green, and blue. By controlling the power supply unit of the control means 900, one lamp group can be selected and lighted, or a plurality of lamp groups can be lighted together to provide various illumination colors.

The reflective film 600 is a reflective film attached to the rear surface of the light guide plate 500. Aluminum is deposited on the entire surface of the reflective film 600 to reflect only a part of the light. As described above, a reflective film is disposed directly in front of the video apparatus 200 to allow the video apparatus 200 to transmit the video of the video apparatus 200 forward when the power is supplied to the video apparatus 200. In addition, as shown in FIGS. 10A and 10B, 200 is cut off or the video output is interrupted, a dark black screen is seen to be seen on the plate surface of the PMMA sheet 400, so that the black screen is projected so that the plate surface according to the forward direction does not look neat, It is possible to prevent the writing from being disturbed by the lecture because the writing is dark and the written letters are not clearly visible.

In this way, since about 60 to 85% of the visible light is transmitted, it is possible to sufficiently view the video device turned on and to sufficiently cover the black screen of the video device 200. [

The control means 900 turns on the power of the video apparatus 200 and controls the power supply to the variable panel unit 300 when the apparatus 900 is used in the electronic formatter mode in which the electronic apparatus can be operated while viewing the screen of the video apparatus 200. [ And cuts off power to the LED light source 510 of the light guide plate 500. In such an electronic writing mode, a transparent state is established as shown in FIG. 11A, so that writing with the screen output of the video apparatus 200 becomes possible.

In addition, when the apparatus is used in a general punching mode in which writing can be performed by a general punching means such as a marker pen, power of the video equipment 200 is turned off, power is turned off to the variable panel unit 300, And applies power to the LED light source 510. 11B, the black screen of the video apparatus 200 is obscured to be opaque, and the general screening means such as a marker pen can be used to make a general screen on the screen. will be.

At this time, the power supply unit is controlled so that only the video output of the cable connecting the computer and the video apparatus 200 is blocked even when the power of the video apparatus 200 is turned on, thereby preventing the video apparatus 200 from outputting the video . Thereby, the control of the video output and the mode switching can be quick and easy, and the lifetime of the video equipment can be increased.

When the optical sheet 1 according to the present invention is attached to the front surface of the PMMA sheet 400, it is possible to track the trajectory of the writing of the electronic pen P, Can be used together.

8A and 8B, the smart electronic whiteboard S, which is transparent and opaque according to the second embodiment of the present invention, includes a frame 100, an image device 200, a variable panel unit 300, A PMMA sheet 400, a light guide plate 500, a reflective film 600, a tempered glass 700, a control means 900 and an optical sheet 1.

The frame frame 100 has a plurality of unit frames 110 connected to form a substantially rectangular frame.

8B, the variable panel unit 300 is coupled to the inside of the frame 100 so as to cover the front of the video apparatus 200, and when the power is supplied or cut off, A PDLC layer 310 formed of a polymer dispersed liquid crystal (PDLC) and transmitting or scattering light, a transparent electrode layer 310 formed on the front and rear surfaces of the PDLC layer 310 and formed of indium-tin oxide A coated ITO layer 320, and a substrate layer 330 formed on the front and rear surfaces of the ITO layer 320, respectively.

The smart electronic writing board S according to the second embodiment of the present invention is a PMMA having a board writing surface coupled to a substrate layer 330 formed in front of the variable panel unit 300, And a LED light source 510 attached to the rear surface of the variable panel unit 300 and made of a transparent material and having a dimming function is installed and is emitted from the LED light source 510 A light guide plate 500 for increasing the sharpness of characters written by diffusing light, and a control unit 900 including a power supply unit for supplying or cutting off power.

However, in the smart electronic whiteboard S according to the second embodiment of the present invention, the tempered glass 700 is installed between the light guide plate 500 and the video apparatus 200. [

The tempered glass 700 is installed in front of the video apparatus 200 to protect the video apparatus 200 and is made transparent so that the strength of the variable panel unit 300 can be enhanced to enable more stable formatting .

The reflective film 600 is attached to the rear surface of the tempered glass 700 and the reflective film 600 is formed by depositing aluminum and reflecting a part of the light to thereby turn off the power or shut off the video output. The black screen is obscured to make it hard to see.

In addition, the control unit 900 includes a wireless communication module and wirelessly receives a control signal from a smart phone or a remote controller R equipped with a dedicated application, so that power control and dimming control can be performed remotely, Can be conveniently controlled and used.

When the optical sheet 1 according to the present invention is attached to the front surface of the PMMA sheet 400, the function of tracking the trajectory of the writing of the electronic pen P, Can be used together.

In addition, when the beam projector is directly projected onto a conventional green board, the brightness and sharpness of the projected image are lowered and the diffused reflection of light is increased, Is attached to the front of the green chalkboard and the beam projector is projected, the visibility and sharpness are increased and the light is not diffused so that the screen is neatly displayed.

As a result, the multilayer optical sheet 1 for writing an electronic pen having a dot pattern according to the present invention is attached to a video apparatus or a blackboard on which an electronic pen is used, and the recognition rate of the electronic pen is greatly increased, The position information can be determined and positioned, the visibility and sharpness of the display screen can be increased, and the scroll can be rolled when the sheet is produced, which makes it easy to store and move.

In addition, the smart electronic blackboard S according to the present invention can use an electronic pen with an optical sheet attached on its front surface, and can selectively use a transparent and opaque display, It is fast and convenient to switch. It can smoothly progress the steel without interruption in the middle. It can not only be written during the video lecture or presentation, it can eliminate the diffuse reflection, and the visibility and sharpness of the image It can be applied to large-scale video equipment or electronic board because it does not need infrared sensor or touch panel to detect the writing means applied to the existing electronic board. It is possible to project the image by projecting the beam projector.

The present invention is not limited to the above-described embodiments. Anything having substantially the same constitution as the technical idea described in the claims of the present invention and achieving the same operational effect is included in the technical scope of the present invention.

1. Optical sheet 10. Pattern film
11. Grid line 12. Crossing point
13, 13a, 13b, 13c, 13d. Dot 20. Diffuse film
21. PET layer 22. Diffusion layer
22a. Round groove 22b. Light diffuser
22c. Light absorber 23. Adhesive layer
30. Protective film 40. Blocking film
41 Base layer 41a. Unevenness
42. AL deposition layer 43. Transmission layer
44. Protective layer 45. Electromagnetic wave blocking layer
45a. Base layer 45b. Board floor
45c. The zirconium oxide layer 45d. The indium-tin oxide layer
45e. Silicon dioxide layer 46. Polyester resin
47. Metal 47a. Pinhole
47b. Metal oxide film 50. Adhesive layer
60. Transparent plate 70. Insert film
100. Frame frame 110. Unit frame 200. Video equipment
300. Variable panel section 310. PDLC layer
320. ITO layer 330. Substrate layer
340. OCA film 400. PMMA sheet
410. Planar surface 500. Light guide plate
510. LED light source 600. Reflective film
700. Tempered glass 900. Control means
P. electronic pen P1. Pen tip
P2. Light source P3. sensor
P4. Power switch P5. Status light
K. Speaker R. Remote control
S. Smart electronic board

Claims (9)

A multi-layer optical sheet for writing electronic pens having a dot pattern formed in a multilayer structure and attached to a front surface of a video apparatus and capable of tracking an electronic pen writing trajectory to display written characters on a screen while being recognized,
A pattern film formed with a gap at an intersection of imaginary lattice lines and having a fine pattern formed of dots whose positional information is encrypted so as to determine positional information of the electronic pen at the time of writing;
An anti-glare coated PET layer formed on the front side of the pattern film and shielding and diffusing a part of light emitted from the imaging device, a plurality of round grooves formed on the front side of the PET layer, A diffusing film comprising a diffusing layer in which a light diffusing agent is randomly distributed to diffuse light forward and a light absorbing agent is applied to the round groove, and an adhesive layer formed behind the PET layer;
A protective film formed on the front side of the diffusion film and made of PET or polycarbonate and treated with an anti glare coating;
A blocking film formed behind the pattern film and shielding a part of the light emitted from the video apparatus to cut off and having a light transmittance of 65 to 90%; And
A pressure sensitive adhesive layer formed on the front side of the shielding film and attached to a front surface of the image display device and having a transparent binder uniformly dispersed with a fine metal particle filler made of copper or silver,
The barrier film may include a base layer formed on one surface so as to have a plurality of irregularities so that the reflection light is uniformly dispersed and the reflectance is increased; An AL evaporation layer deposited on one surface of the substrate layer to reflect a part of light; A transparent transparent layer formed on one side of the AL deposition layer to transmit light; A protective layer coated on one side of the transmissive layer; And an electromagnetic wave shielding layer formed on an opposite surface of the base layer and shielding electromagnetic waves,
Wherein the electromagnetic wave shielding layer comprises a base layer in which one or more fine metal particles selected from copper, silver and nickel are uniformly dispersed in a transparent synthetic resin, a board layer on which the vinyl methyl dichloro silane is applied, An indium tin oxide layer deposited on the zirconium oxide layer; and a silicon dioxide layer deposited on the indium-tin oxide layer.
A multi-layer optical sheet for writing electronic pens having a dot pattern formed in a multilayer structure and attached to a front surface of a video apparatus and capable of tracking an electronic pen writing trajectory to display written characters on a screen while being recognized,
A pattern film formed with a gap at an intersection of imaginary lattice lines and having a fine pattern formed of dots whose positional information is encrypted so as to determine positional information of the electronic pen at the time of writing;
An anti-glare coated PET layer formed on the front side of the pattern film and shielding and diffusing a part of light emitted from the imaging device, a plurality of round grooves formed on the front side of the PET layer, A diffusing film comprising a diffusing layer in which a light diffusing agent is randomly distributed to diffuse light forward and a light absorbing agent is applied to the round groove, and an adhesive layer formed behind the PET layer;
A protective film formed on the front side of the diffusion film and made of PET or polycarbonate and treated with an anti glare coating;
A blocking film formed behind the pattern film and shielding a part of the light emitted from the video apparatus to cut off and having a light transmittance of 65 to 90%; And
A pressure sensitive adhesive layer formed on the front side of the shielding film and attached to a front surface of the image display device and having a transparent binder uniformly dispersed with a fine metal particle filler made of copper or silver,
The barrier film may include a base layer formed on one surface so as to have a plurality of irregularities so that the reflection light is uniformly dispersed and the reflectance is increased; An AL evaporation layer deposited on one surface of the substrate layer to reflect a part of light; A transparent transparent layer formed on one side of the AL deposition layer to transmit light; A protective layer coated on one side of the transmissive layer; And an electromagnetic wave shielding layer formed on an opposite surface of the base layer and shielding electromagnetic waves,
Wherein the electromagnetic wave shielding layer comprises a linear metal material having a polyester resin and a plurality of metal oxide films randomly dispersed in the polyester resin and having pinholes formed therein and having different types laminated thereon, A plurality of metal oxide films selected from zirconium oxide, indium-tin oxide and silicon dioxide are coated on natural fibers or synthetic fibers having a diameter of 2.6 to 5 mu m to a thickness of 2.6 to 5 mu m, To 750 [deg.] C to selectively remove only natural fibers or synthetic fibers to form pinholes, thereby forming a rod-like hollow fiber capable of absorbing electromagnetic waves. Optical sheet.
3. The method according to claim 1 or 2,
Wherein the diffusing film is formed on a rear surface of the pattern film.
The method of claim 3,
Wherein the patterned film has an insert film made of PET or polycarbonate and coated with an antiglare coating between the diffusion film formed on the back surface of the patterned film and the barrier film.
delete delete 3. The method according to claim 1 or 2,
A transparent translucent plate is formed between the pattern film and the barrier film,
Wherein the transparent plate is made of one selected from an acrylic plate, a polycarbonate plate, and a glass plate.
A frame frame formed by connecting a plurality of unit frames;
A video device having a flat or curved display panel installed at an inner rear side of the frame frame and outputting an image;
(PDLC), which is coupled to the inside of the frame frame and covers the front of the video equipment and is transparent or opaque according to supply and interruption of power supply, and is made of polymer dispersed liquid crystal (PDLC) A variable panel portion including a scattered PDLC layer, an ITO layer formed on the front and rear surfaces of the PDLC layer and coated with indium-tin oxide, and a substrate layer formed on an outer surface of each ITO layer;
A PMMA sheet having a plate surface joined to a substrate layer formed in front of the variable panel portion and made of a plate;
A light guide plate attached to a rear surface of the variable panel unit and having a dimming function and provided with a dimming function and diffusing light emitted from the LED light source when power is applied to increase the sharpness of letters written;
A reflective film attached to a rear surface of the light guide plate and deposited on aluminum to reflect a part of the light to prevent the screen of the video device from being visibly turned off;
Control means for controlling the brightness of the LED light source and having a power supply unit for supplying power; And
And a multi-layer optical sheet having a dot pattern attached to the front surface of the PMMA sheet and capable of tracking an electronic pen writing locus to display written characters on a screen while recognizing handwriting,
The optical sheet includes a pattern film formed with a gap at an intersection of virtual lattice lines and having a fine pattern formed of dots whose positional information is encrypted so as to determine positional information of the electronic pen at the time of writing; An anti-glare coated PET layer formed on the front side of the pattern film and shielding and diffusing a part of light emitted from the imaging device, a plurality of round grooves formed on the front side of the PET layer, A diffusing film comprising a diffusing layer in which a light diffusing agent is randomly distributed to diffuse light forward and a light absorbing agent is applied to the round groove, and an adhesive layer formed behind the PET layer; A protective film formed on the front side of the diffusion film and made of PET or polycarbonate and treated with an anti glare coating; A blocking film formed behind the pattern film and shielding a part of the light emitted from the video apparatus to cut off and having a light transmittance of 65 to 90%; And a pressure sensitive adhesive layer formed on the front side of the barrier film and attached to the front side of the barrier film and having a transparent binder uniformly dispersed with minute metal particle fillers made of copper or silver, A base layer formed uniformly so as to uniformly disperse the reflected light and increase the reflectance; An AL evaporation layer deposited on one surface of the substrate layer to reflect a part of light; A transparent transparent layer formed on one side of the AL deposition layer to transmit light; A protective layer coated on one side of the transmissive layer; And an electromagnetic wave shielding layer formed on the opposite surface of the base layer to shield electromagnetic waves, wherein the electromagnetic wave shielding layer comprises a polyester resin, and a resin dispersed irregularly in the polyester resin, Wherein the metal material is selected from the group consisting of zirconium oxide, indium-tin oxide, and silicon dioxide in a natural fiber or synthetic fiber having a diameter of 2.6 to 5 탆, and a plurality of metal oxide films Of the metal oxide films are respectively coated to a thickness of 2.6 to 5 탆 and heat treated at a temperature of 650 to 750 캜 in an inert gas atmosphere to selectively remove only natural fibers or synthetic fibers to form pinholes, A smart electronic blackboard characterized by forming a bar-shaped hollow fiber.
A frame frame formed by connecting a plurality of unit frames;
A video device having a flat or curved display panel installed at an inner rear side of the frame frame and outputting an image;
(PDLC), which is coupled to the inside of the frame frame and covers the front of the video equipment and is transparent or opaque according to supply and interruption of power supply, and is made of polymer dispersed liquid crystal (PDLC) A variable panel portion including a scattered PDLC layer, an ITO layer formed on the front and rear surfaces of the PDLC layer and coated with indium-tin oxide, and a substrate layer formed on an outer surface of each ITO layer;
A PMMA sheet having a plate surface joined to a substrate layer formed in front of the variable panel portion and made of a plate;
A light guide plate attached to a rear surface of the variable panel unit and having a dimming function and provided with a dimming function and diffusing light emitted from the LED light source when power is applied to increase the sharpness of letters written;
A tempered glass provided between the light guide plate and the video apparatus;
A reflection film attached to the rear surface of the tempered glass and deposited on aluminum to reflect a part of the light to prevent the screen of the video equipment turned off from being visible;
Control means for controlling the brightness of the LED light source and having a power supply unit for supplying power; And
And a multi-layer optical sheet having a dot pattern attached to the front surface of the PMMA sheet and capable of tracking an electronic pen writing locus to display written characters on a screen while recognizing handwriting,
The optical sheet includes a pattern film formed with a gap at an intersection of virtual lattice lines and having a fine pattern formed of dots whose positional information is encrypted so as to determine positional information of the electronic pen at the time of writing; An anti-glare coated PET layer formed on the front side of the pattern film and shielding and diffusing a part of light emitted from the imaging device, a plurality of round grooves formed on the front side of the PET layer, A diffusing film comprising a diffusing layer in which a light diffusing agent is randomly distributed to diffuse light forward and a light absorbing agent is applied to the round groove, and an adhesive layer formed behind the PET layer; A protective film formed on the front side of the diffusion film and made of PET or polycarbonate and treated with an anti glare coating; A blocking film formed behind the pattern film and shielding a part of the light emitted from the video apparatus to cut off and having a light transmittance of 65 to 90%; And a pressure sensitive adhesive layer formed on the front side of the barrier film and attached to the front side of the barrier film and having a transparent binder uniformly dispersed with minute metal particle fillers made of copper or silver, A base layer formed uniformly so as to uniformly disperse the reflected light and increase the reflectance; An AL evaporation layer deposited on one surface of the substrate layer to reflect a part of light; A transparent transparent layer formed on one side of the AL deposition layer to transmit light; A protective layer coated on one side of the transmissive layer; And an electromagnetic wave shielding layer formed on the opposite surface of the base layer to shield electromagnetic waves, wherein the electromagnetic wave shielding layer comprises a polyester resin, and a resin dispersed irregularly in the polyester resin, Wherein the metal material is selected from the group consisting of zirconium oxide, indium-tin oxide, and silicon dioxide in a natural fiber or synthetic fiber having a diameter of 2.6 to 5 탆, and a plurality of metal oxide films Of the metal oxide films are respectively coated to a thickness of 2.6 to 5 탆 and heat treated at a temperature of 650 to 750 캜 in an inert gas atmosphere to selectively remove only natural fibers or synthetic fibers to form pinholes, A smart electronic blackboard characterized by forming a bar-shaped hollow fiber.

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