RU2603544C2 - Input device - Google Patents

Abstract

FIELD: instrument making.

SUBSTANCE: invention relates to a pointing input device. Result is achieved due to providing a magnetic field shielding layer, which does not affect operation of the geomagnetic sensor in the touchscreen type pointing input device using an electromagnetic pen. Magnetic field shielding layer is made from a magnetic metal powder. Magnetic field shielding layer is formed directly on the pointing input device without the need of a separate adhesive layer.

EFFECT: technical result is elimination of errors caused by disturbance of magnetic field.

15 cl, 13 dwg

Description

FIELD OF THE INVENTION

The present invention relates generally to a pointing input device, and more particularly, although not exclusively, to a pointing input device having a magnetic field shielding layer that transmits a magnetic field of the earth detected by a geomagnetic sensor.

State of the art

With the rapid development of markets related to smartphones or touch screens, research is being conducted on these devices. The touch screen is widely used as an input device of a mobile terminal and, in general, includes a transparent electrode. A capacitive type touch screen is usually used, which measures the change in electrostatic capacitance that occurs due to touch. However, in a capacitive type touch screen, the user must provide a predetermined pressure or displacement by contact with the touch screen and cannot perform an input operation by using a pen.

To overcome these shortcomings, a touch screen using electromagnetic waves has recently become popular. A pointing input device using this circuit can be classified into various types, an example of which is the type of electromagnetic resonance (EMR).

However, an electronic device, such as a mobile terminal, etc., often includes a mounting device for mounting a pointing input device, a battery, various circuit blocks, etc. that can block or disturb the magnetic field. As a result, the functioning of the pointing input device is adversely affected. To prevent such a negative effect, a magnetic field shielding layer is used.

The mobile terminal uses various additional functions to improve the convenience and entertainment for the user. For example, a screen change is provided in accordance with the amount of movement of the mobile terminal. To detect movement, the mobile terminal is equipped with a geomagnetic sensor. However, if the geomagnetic sensor is provided in the pointing input device, the magnetic field shielding layer may affect the operation of the geomagnetic sensor.

In addition, components having strong magnets, such as a speaker, a camera, etc., as well as a geomagnetic sensor, are installed in the mobile terminal. Such magnetic components generate a strong low-frequency magnetic field, and thus there is a need for a magnetic field shielding layer.

Disclosure of invention

Technical problem

The magnetic field shielding layer prevents eddy current induction, making it possible to accurately track the position of the electromagnetic pen. However, if the geomagnetic sensor is located next to the magnetic field shielding layer, a low-frequency magnetic field, such as the earth’s magnetic field, is blocked or disturbed by the magnetic field shielding layer, which makes it difficult to perform an accurate geomagnetic recognition operation.

Therefore, there is a need for a magnetic field shielding layer that prevents the magnetic field from attenuating by blocking the magnetic field generated by a mounting device, battery, various circuits, etc., placed under the magnetic field shielding layer, and at the same time passes the magnetic field of the earth recognized through a geomagnetic sensor, and does not affect the operation of the geomagnetic sensor. Moreover, when a pointing input device, such as a mobile terminal, includes magnetic components, a magnetic field shielding layer is required that effectively blocks a strong low-frequency magnetic field signal and at the same time transmits a low-frequency magnetic field, guaranteeing the operation of the geomagnetic sensor.

Solution

The aim of some embodiments of the invention is to solve, weaken or eliminate, at least partially, at least one of the problems and / or disadvantages associated with the prior art. Some embodiments are intended to provide at least one of the advantages described below.

Accordingly, the aim of some embodiments of the present invention is to provide a pointing input device having a magnetic field shielding layer that does not affect the operation of the geomagnetic sensor.

Another objective of some embodiments of the present invention is to provide an pointing input device having a magnetic field shielding layer that partially passes the applied magnetic field to enable the geomagnetic sensor to recognize the earth's magnetic field.

Another objective of some embodiments of the present invention is to provide an pointing input device having a magnetic field shielding layer that allows the geomagnetic sensor to recognize the earth's magnetic field and effectively blocks the magnetic field signal generated by the magnetic components.

According to one aspect of the present invention, there is provided an input device including a display unit for outputting (e.g. displaying) a display screen, an electromagnetic radiation recognition unit located below the display unit to recognize a magnetic field generated from an electromagnetic pen when approaching or contacting a surface ( for example, the top surface) of the display unit, a partial shielding layer of the magnetic field, located under the electromagnetic radiation recognition unit an array in which magnetic powder is distributed (e.g., dispersed), and a sensor (e.g., a geomagnetic sensor) housed in an input device to recognize a magnetic field applied through a partial shielding layer of the magnetic field.

Preferred Effects of the Invention

The magnetic field shielding layer according to one embodiment of the present invention prevents the magnetic field generated by the electromagnetic pen from reaching the conductor located under the magnetic field shielding layer and minimizes the effect on the operation of the geomagnetic sensor installed in the pointing input device.

Moreover, by using magnetic powder in the electromagnetic shielding layer according to one embodiment of the present invention, the electromagnetic shielding layer is formed directly in the pointing input device without a separate adhesive layer, thereby reducing the thickness of the pointing input device.

Additionally, embodiments of the present invention minimize the effect on the geomagnetic sensor and maximize the sensitivity of the geomagnetic sensor by using a mixture of different magnetic powders.

In addition, a magnetic field shielding layer having a low magnetic field shielding property, such as a magnetic powder material, and a magnetic field shielding layer having a higher shielding property, such as an amorphous metal, are arranged according to the positions of the geomagnetic sensor, loudspeaker and camera, guaranteeing both the functioning of the geomagnetic sensor, and the functioning of the pointing input device.

Brief Description of the Drawings

The above and other features and advantages of embodiments of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which:

FIG. 1 illustrates a cross section of a pointing input device having a magnetic field shielding layer, according to one embodiment of the present invention;

FIG. 2 illustrates the attenuation of a magnetic field caused by eddy current;

FIG. 3 illustrates a cross-sectional view of a pointing input device as an example of comparison;

FIG. 4A and 4B are graphs illustrating characteristics of a magnetic field sensor when a standard amorphous metal is used;

FIG. 5 is a graph illustrating permeability characteristics of an amorphous metal with respect to frequency;

FIG. 6 is a graph illustrating the permeability characteristics of an amorphous metal and magnetic powder with respect to frequency;

FIG. 7 illustrates a cross-sectional view for describing a shape in which a magnetic field shielding layer is disposed according to one embodiment of the present invention;

FIG. 8 is a diagram illustrating a form in which a magnetic field shielding layer is arranged according to one embodiment of the present invention;

FIG. 9 is a cross-sectional view of FIG. 8;

FIG. 10 is a graph illustrating characteristics of a geomagnetic sensor when magnetic powder material is used according to one embodiment of the present invention;

FIG. 11 is a graph illustrating a sensitivity comparison when amorphous metal and magnetic powder having a permeability of 150 μ0 are used, according to one embodiment of the present invention; and

FIG. 12 is a cross-sectional view illustrating a form in which a magnetic field shielding layer is arranged according to a further embodiment of the present invention.

Best Mode for Carrying Out the Invention

Below, embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be noted that identical components are indicated by identical reference numbers throughout the drawings. A detailed description of the functions and configurations included herein, which are well known to those skilled in the art, will be omitted in order to avoid unnecessary difficulty in understanding the present invention.

The present invention provides a magnetic field shielding layer that does not affect the operation of the geomagnetic sensor in a pointing input device such as a touch screen using an electromagnetic pen. The magnetic field shielding layer includes a metal powder material. A magnetic field shielding layer can be formed directly on the pointing input device without a separate adhesive layer, by mixing the magnetic powder and adhesive and applying the mixture.

Briefly describes the principles of operation of the pointing input device type electromagnetic resonance (EMR) used in embodiments of the present invention. This type of pointing input device includes a touch screen.

As shown in FIG. 1, in an EMR type pointing device, the loop coil 110 is placed on the electromagnetic radiation recognition unit 115, and current is supplied to the loop coil 110 so that a magnetic field 126 is generated, and the generated magnetic field is absorbed by the electromagnetic pen 102. The electromagnetic pen 102 includes a capacitor 100 and coil 105 and emits an absorbed magnetic field 127 at a predetermined frequency. In other words, the magnetic field 126 generated by the loop coil 110 induces a current in the pen resonance circuit, and this induced current flowing in the pen coil 105 generates a corresponding magnetic field 127.

The magnetic field emitted by the electromagnetic pen 102 is absorbed by the loop coil 110 of the electromagnetic radiation recognition unit 115, so that the electromagnetic radiation recognition unit 115 determines which position of the pointing input device the electromagnetic pen 102 is close to.

As such, the electromagnetic radiation recognition unit 115 includes a plurality of loop coils 110, a plurality of loop coils 110 are arranged to overlap each other. When the user moves the electromagnetic pen 102 close to a specific part of the plurality of loop coils 110, the plurality of loop coils 110 recognizes the magnetic field generated from the electromagnetic pen 102. Thus, each of the plurality of loop coils 110 outputs a current induced by a recognized magnetic field. Since the loop coil 110 is located closer to the electromagnetic pen 102, it recognizes a magnetic field having a larger amplitude and emits a corresponding induced current. Thus, a plurality of loop coils 110 output induced currents of various sizes, so that by measuring the terminals of the loop coils 110, the position of the electromagnetic pen 102 is tracked. In other words, the pen magnetic field (generated as a result of the current induced into the pen by the magnetic field generated by the loop coil ) affects (i.e. changes) the current in the loop coil, above which the pen is located. This effect (change) can be detected and used as an indication of the position of the pen.

Under the electromagnetic radiation recognition unit 115, a magnetic field shielding layer 120 is provided. Under the magnetic field shielding layer 120, a printed circuit board (PCB) unit 130 is provided in which a mounting device (which can be described as mounting means) for securely installing a pointing input device, a battery and various circuit blocks, etc. Layer 120 battery and various circuit blocks, etc. the magnetic field shielding layer 120 blocks the magnetic field generated from the circuit blocks, etc., located on the PCB block 130 under the magnetic field shielding layer 120 to prevent a weakening of the magnetic field.

FIG. 2 illustrates the principle of a magnetic field shielding layer. FIG. 2 suggests that a magnetic field is applied to a metal bracket, which is a conductive material 201 having low resistance, without a shield layer of the magnetic field. When a magnetic field is applied to a material having a low electrical resistance, eddy current 202 is generated. The eddy current generates a magnetic field opposite to the applied magnetic field of the coil, thereby generating an eddy current magnetic field 203. As a result, the magnetic field of the coil is weakened by the magnetic field 203 of the eddy current and, thus, decreases. Therefore, when the intensity of the magnetic field emitted by the electromagnetic pen 102 decreases, the maximum distance required for recognizing the magnetic field decreases, increasing the likelihood of a malfunction. That is, the electromagnetic pen 102 can be recognized within the maximum distance by the electromagnetic radiation recognition unit 115.

To prevent such a phenomenon, a magnetic field shielding layer 120 is used. In this case, the magnetic field 200 of the coil does not pass under the magnetic field shielding layer 120, so that eddy current is not generated, even when under the layer 120 itself, prevents the weakening of the magnetic field. Therefore, the magnetic field of the coil reaches the electromagnetic radiation recognition unit 115 adjacent to the magnetic field shielding layer 120 without attenuating the magnetic field, so that the magnetic field induced by the electromagnetic pen 102 can be recognized.

In general, a thin film of an alloy formed of silicon (Si) based on iron (Fe) is used for the magnetic field shielding layer for the pointing input device. Recently, an amorphous metal has been used, created by mixing iron (Fe), silicon (Si) and boron (B) with a change in the crystal structure of the mixture. An amorphous metal is a material that has a superior magnetic field shielding characteristic with high permeability and conductivity with respect to the magnetic field in the range of several hundred kHz and low frequency range, which are generally used for a pointing input device. In particular, an amorphous metal has a much higher permeability than other materials in DC (forward current).

However, when the geomagnetic sensor 125 is located adjacent to the magnetic field shielding layer 120 formed of an amorphous metal, illustrated in FIG. 3, the earth’s magnetic field detected by the geomagnetic sensor 125 may be blocked or disturbed by the magnetic field shielding layer 120. In other words, due to the fact that the amorphous metal has high DC permeability, the geomagnetic sensor 125 has a difficulty in recognizing the earth's magnetic field, which is the DC magnetic field.

An evaluation of the characteristics of the geomagnetic sensor when an amorphous metal is used is illustrated in FIG. 4B. In FIG. 4A and 4B, the graphs show the conclusions of the geomagnetic sensor without and with the presence of amorphous metal, respectively, when a DC magnetic field is applied by rotation around the geomagnetic sensor. The direction of the applied magnetic field is determined by the ratio of the components of the output direction of the geomagnetic sensor, that is, the ratio of the terminals along the X and Y axes of the graph. Therefore, in order to know the exact direction of the magnetic field, the geomagnetic sensor must have the same sensitivity for the direction of the magnetic field along the X and Y axes. For example, when the magnetic field is applied in the direction of 4–5 degrees, the magnetic field strengths measured on the corresponding axes should be are equal.

Therefore, if a magnetic field of a predetermined force is applied to all directions during the normal operation of the geomagnetic sensor, the magnetic field forces in the X and Y directions are such that one decreases if the other increases, and thus the vector sum of the two forces forms a predetermined shape , i.e., a circle, as illustrated in FIG. 4A.

When a magnetic body exists near the geomagnetic sensor, the center of the circle shown in FIG. 4A moves, or the shape of the circle shown in FIG. 4A changes to an oval shape, as illustrated in FIG. 4B. The graph shown in FIG. 4B shows that disturbances in the normal operation of the geomagnetic sensor due to blocking or disturbance of the earth’s magnetic field are caused by an amorphous metal. Moreover, the amorphous metal has a strong residual field, so that when a strong magnetic field is applied to the amorphous metal, the amorphous metal maintains a magnetized state, thereby serving as a permanent magnet. Subsequently, the effect on the geomagnetic sensor is continuously maintained.

FIG. 5 illustrates the permeability characteristics of an amorphous metal with respect to frequency. The permeability shown in FIG. 5 is higher than 1000 µ0 in a frequency range of 100 kHz or less. µ0 is defined as vacuum permeability. From FIG. 5, it can be seen that the effect of amorphous metal on the geomagnetic sensor is significant.

Therefore, a pointing input device having a magnetic field recognition function, such as a geomagnetic sensor, needs a magnetic field shielding layer that can perform a magnetic field shielding function without affecting the geomagnetic sensor.

One embodiment of the present invention provides a magnetic field shielding layer formed from magnetic powder material. FIG. 6 illustrates the characteristics of a magnetic powder material, an amorphous metal has a permeability of 170 μ0 or more in the range of 500 kHz and has a permeability of 10,000 μ0 or more in the frequency range of less than 500 kHz, as illustrated in FIG. 5. In this case, the earth’s magnetic field is blocked or disturbed by the amorphous metal, so that the geomagnetic sensor cannot work to detect the earth’s magnetic field.

The magnetic powder material used in one embodiment of the present invention has a permeability of 100 μ0 in the range of 500 kHz and maintains this permeability over a large frequency domain. Moreover, similar permeability is provided in the DC range. Therefore, taking into account that the DC permeability of the amorphous metal is greater than 10,000 μO, the permeability of the magnetic powder material is 1/100 of the permeability of the amorphous metal, so that the influence of the magnetic powder on the geomagnetic sensor is minimized.

Although the permeability in the 500 kHz range is 100 μO as an example, a magnetic field shielding layer can be formed to have a permeability of 150 μ0 by using a magnetic powder material. In this case, the magnetic field shielding layer has a permeability similar to that of the amorphous metal in the primary range, without having a large impact on the functioning of the pointing input device, which thereby blocks the magnetic field induced by the electromagnetic pen. In addition, the permeability of the material of the magnetic powder is maintained at a relatively low level in the large frequency domain, so that the earth's magnetic field recognized by the geomagnetic sensor is passed through.

FIG. 7 illustrates a form in which a magnetic field shielding layer composed of a magnetic powder material is disposed according to one embodiment of the present invention.

FIG. 7 is a cross-sectional view of the pointing input device shown in FIG. 1. The pointing input device includes a display unit 700, an electromagnetic radiation recognition unit 115, a magnetic field shielding layer 120, a geomagnetic sensor 125, and a PCB unit 130.

The display unit 700 is an area for displaying user-recognizable visual information. The display unit 700 receives an external input of a control signal or a graphic signal and displays a display screen corresponding to a control signal or a graphic signal. The display unit 700 is preferably a liquid crystal display (LCD) module, but there is no restriction on the type of the display unit 700, as those skilled in the art should readily understand.

The electromagnetic radiation recognition unit 115 is adjacent to the bottom surface of the display unit 700. The structure of the electromagnetic radiation recognition unit 115 is the same as described above with reference to FIG. 1. The electromagnetic radiation recognition unit 115 recognizes electromagnetic radiation incident from the electromagnetic pen that approaches or contacts the upper surface of the display unit 700, thereby determining a point selected by the user.

A geomagnetic sensor 125 is located in the pointing input device and recognizes a portion of the earth's magnetic field applied through the magnetic field shielding layer 120. The geomagnetic sensor 125 is located under the magnetic field shielding layer 120, which the magnetic field of the electromagnetic pen does not affect. As another example, a geomagnetic sensor 125 is located on the PCB unit 130.

The PCB unit 130 includes various electronic components configured to electrically operate and control a pointing input device. A magnetic field including electromagnetic waves generated from various electronic components of the PCB unit 130 is blocked by a magnetic field shielding layer 120 composed of magnetic powder material.

The magnetic field shielding layer 120 according to one embodiment of the present invention is formed from a magnetic powder material and placed under the electromagnetic radiation recognition unit 115. The magnetic field shielding layer 120 is a partial shielding layer configured to partially pass the applied magnetic field and is formed by distributing (for example, scattering) the magnetic powder. Magnetic metal powder called ferrite, MolyPermalloy powder (MPP), Fe-Si-Al based material (Sandust), Ni-Fe based material (Highflux), or the like can be used. Since the magnetic powder is in powder form, it is applied after mixing with an adhesive such as a polymer (e.g. PP (polypropylene), PE (polyethylene), etc.). Amorphous metal powder and magnetic powder are preferably used together, and magnetic metal powder and the amorphous metal powder is mixed with the adhesive to form a magnetic field shielding layer 120.

The magnetic field shielding layer 120 formed from the magnetic powder has different permeability and different density of the magnetic powder. As the density of the magnetic powder increases, the permeability of the magnetic field shielding layer 120 increases. Thus, the density of the magnetic powder of the magnetic field shielding layer 120 is adjusted to obtain a permeability similar to that when a metal thin film is used, but unlike when a metal thin film is used, the earth’s magnetic field is passed, so that the geomagnetic sensor 125 no effect.

The permeability of the magnetic field shielding layer 120 is different depending on the mixing ratio of the magnetic powder mixed with the polymer to form the magnetic field shielding layer 120, i.e., the density of the magnetic powder. The density of the magnetic powder, that is, the mixing ratio, is preferably set so that the permeability of the magnetic field shielding layer 120 is 100 ~ 200 μ0 in the DC range. In this way, the output characteristics of the geomagnetic sensor illustrated in FIG. 10, and these characteristics are similar to those shown in FIG. 4A, which corresponds to the absence of an amorphous metal. That is, when magnetic powder material is used, the geomagnetic sensor 125 is operating normally.

Such magnetic powder is mixed with adhesive and adhered to the electromagnetic radiation recognition unit 115. Thus, when compared with a standard magnetic field shielding layer for which an adhesive is applied and then a metal thin film is subsequently bonded, the magnetic field shielding layer 120 does not need a separate adhesive layer, which contributes to a decrease in thickness. In other words, the material of the magnetic powder is in a liquid state when mixed with the adhesive, and can thus be uniformly applied to the electromagnetic radiation recognition unit 115. As such, unlike when a standard metallic thin film is used, the magnetic powder material is uniformly applied, so that uniform shielding can be obtained over the entire surface of the magnetic field shielding layer 120. Moreover, the magnetic field shielding layer 120 is directly bonded to the pointing input device without a separate adhesive layer, which simplifies processing and reduces the additional thickness corresponding to the thickness of the standard adhesive layer.

As described above, the material of the magnetic powder can be deposited on, for example, the surface of the electromagnetic radiation recognition unit 115 in the pointing input device. Alternatively, the magnetic powder material may be applied to an adhesive film having adhesion, and then to a surface in a pointing input device.

The residual magnetic field of the magnetic powder material is not strong, unlike when a thin film of amorphous metal is used, so that even when a strong magnetic field is applied to the magnetic powder material, the material of the magnetic powder does not affect the operation of the geomagnetic sensor. However, a pointing input device having a magnetic field shielding layer 120 using a magnetic powder material, when placed on a magnetic field disturbing material such as a conductor, may experience deterioration in sensitivity due to the influence of the eddy current, the creation of a magnetic field, or the degradation of absorption characteristics. However, such a deterioration

sensitivity is relative in comparison with a thin film of amorphous metal and has the proper sensitivity level for the pointing input device illustrated in FIG. eleven.

FIG. 11 is a graph illustrating sensitivity comparison when amorphous metal and magnetic powder are used according to one embodiment of the present invention. In FIG. 11, the signal strength of a touchscreen that uses a magnetic powder material having a permeability of 150 μ0 and a thickness of 50 μm and a thin film of an amorphous metal having a thickness of 25 μm is measured. As shown in FIG. 11, the material of the magnetic powder may have a lower sensitivity than a thin film of an amorphous metal, but its sensitivity can be adjusted by adjusting the thickness to obtain the desired sensitivity. The thickness of the magnetic field shielding layer 120, according to one embodiment of the present invention, is preferably 50 μm or more. Since the permeability of the magnetic field shielding layer 120 varies according to the thickness of the magnetic field shielding layer 120, the thickness must be set according to the required permeability.

According to one embodiment of the present invention, a magnetic field shielding layer is formed, as illustrated in FIG. 8. In FIG. 8, a magnetic field shielding layer 805 using magnetic powder, i.e. a magnetic powder shielding layer, is arranged around the geomagnetic sensor 800, and a magnetic field shielding layer 810 using a thin amorphous metal film, i.e., an amorphous metal shielding layer, is placed on another area. For example, when the geomagnetic sensor 800 is positioned in the center, a magnetic powder shielding layer 805 is placed around the geomagnetic sensor 800 to ensure that the geomagnetic sensor 800 is operating normally, and the amorphous metal shielding layer 810 is placed in a different area to improve sensitivity.

The arrangement illustrated in FIG. 9. FIG. 9 illustrates a cross section of an arrangement of a magnetic powder shielding layer 805 and an amorphous metal shielding layer 810, including a display unit 815 here. The magnetic field shielding layer includes a magnetic powder shielding layer 805 in which magnetic powder is dispersed to partially transmit the applied magnetic field of the earth, and an amorphous metal shielding layer 810 that uses a thin amorphous metal film to block the applied magnetic field. The positions of the magnetic powder shielding layer 805 and the amorphous metal shielding layer 810 are changed according to the position of the geomagnetic sensor 800.

In another embodiment shown in FIG. 8 and 9, a portion of the entire magnetic field shielding layer corresponding to the position of the geomagnetic sensor 800 is formed as a magnetic powder shielding layer 805 using magnetic powder. By using magnetic powder, a low-frequency magnetic field, such as a magnetic field of the earth, detected by the geomagnetic sensor 800, is transmitted, but transmission of the magnetic field of the frequency used for indicating is limited. However, another part of the magnetic field shielding layer is formed from the amorphous metal shielding layer 810, which impedes the magnetic field generated according to the arrangement of the mounting device, battery, various circuit blocks, and so on, on which the pointing input device is mounted.

However, the amorphous metal shielding layer 810 is formed in a region other than the region where the magnetic powder shielding layer 805 is formed, as shown in FIG. 8 and 9, so that the earth’s magnetic field is partially blocked by the amorphous metal shielding layer 810, which impairs the functioning of the geomagnetic sensor 800 compared with the structure of the magnetic field shielding layer 120 shown in FIG. 7. For example, in FIG. 7 according to one embodiment of the present invention, the entire magnetic field shielding layer 120 is formed of magnetic powder, regardless of the position of the geomagnetic sensor 125, so that the magnetic powder shielding layer 120 does not block the earth's magnetic field and therefore does not affect the operation of the geomagnetic sensor 125.

Therefore, one embodiment of the present invention provides the structure of a magnetic field shielding layer illustrated in FIG. 12. In particular, the embodiment of the present invention illustrated in FIG. 12 provides the structure of a magnetic field shielding layer where a magnetic component is mounted to generate a strong low-frequency magnetic field other than a geomagnetic sensor.

Although the speaker and camera 1230 are mounted as examples of magnetic components 1230 on the side of the PCB unit 130 in FIG. 12, magnetic components 1230 are also located on the PCB unit 130. The magnetic field generated in the magnetic components 1230 passes through the shielding layer of the magnetic powder, thereby affecting the operation of the pointing input device. For example, for electromagnetic waves, the magnetic field generated in the magnetic component changes the frequency and strength of the signal generated in the pen, interrupting the pen. However, if the magnetic field shielding layer having the highest shielding property, such as an amorphous metal, replaces the magnetic powder shielding layer 120 shown in FIG. 7, in order to block the magnetic field generated in the magnetic component, the amorphous metal shielding layer affects the functioning of the geomagnetic sensor 125.

Therefore, taking into account the above points, the embodiment of the present invention illustrated in FIG. 12 provides a structure that effectively blocks the magnetic field generated by the magnetic components 1230 without affecting the operation of the geomagnetic sensor 800.

The structure of the magnetic field shielding layer illustrated in FIG. 12 differs from the structure of the magnetic field shielding layer shown in FIG. 7, in that the amorphous metal shielding layer 1220 is placed under the magnetic powder shielding layer 1210 and in proximity to the magnetic component that generates a strong low-frequency magnetic field, such as a speaker / camera 1230. The amorphous metal shielding layer 1220 is placed under the magnetic powder shielding layer 1210 formed on the surface of the electromagnetic radiation recognition unit 115, and in proximity to the speaker / camera 1230 in close contact with the magnetic powder shielding layer 1210. The amorphous metal shielding layer 1220 is in close contact with a portion of the surface of the magnetic powder shielding layer 1210 rather than its entire surface, and the size and position of the amorphous metal shielding layer 1220 are such that they can block the magnetic field generated by the magnetic components 1230, and thus vary according to the size and position of the magnetic component.

The magnetic field shielding layer according to one embodiment of the present invention prevents the magnetic field generated by the electromagnetic * pen from reaching the conductor located under the magnetic field shielding layer and minimizes the effect on the operation of the geomagnetic sensor installed in the pointing input device.

Moreover, by using magnetic powder in the electromagnetic shielding layer according to one embodiment of the present invention, the electromagnetic shielding layer is formed directly in the pointing input device without a separate adhesive layer, thereby reducing the thickness of the pointing input device.

Additionally, embodiments of the present invention minimize the effect on the geomagnetic sensor and maximize the sensitivity of the geomagnetic sensor by using a mixture of different magnetic powders.

In addition, a magnetic field shielding layer having a low magnetic field shielding property, such as a magnetic powder material, and a magnetic field shielding layer having a higher shielding property, such as an amorphous metal, are arranged according to the positions of the geomagnetic sensor, loudspeaker and camera, which ensures both functioning geomagnetic sensor, and the functioning of the pointing input device.

Throughout the description and claims, the materials of the application include “include” and “contain” and variations of said features, for example, “including” and “comprising”, mean “including but not limited to,” and are not intended (and do not) to exclude other components, additives, constituents, integers or steps.

Throughout the description and claims, in the application materials, a single encompasses the plural, unless the context otherwise requires. In particular, where the singular form is used, the application materials should be understood as providing for plurality as well as singularity, unless the context otherwise requires.

Signs, integers, characteristics, constituents, chemical components or groups described in connection with a particular aspect, embodiment or example of the invention should be understood as applicable to any other aspect, embodiment or example described herein, unless compatible ones.

You should also take into account that throughout the description and claims in the application materials, the language is in the general form of the form “X for Y” (where Y is some action, activity or step, and X is some means for performing this action, activity or step ) encompasses means X adapted or specifically configured to, but not exclusively, to implement Y.

While the invention has been shown and described with reference to its embodiments, those skilled in the art should understand that various changes can be made in form and detail without departing from the scope of the invention as defined by the appended claims and their equivalents.

Claims (15)

1. An input device comprising:
a display unit for displaying a display screen;
an electromagnetic radiation recognition unit located below the display unit to recognize a magnetic field generated by the electromagnetic pen when approaching or contacting the upper surface of the display unit;
a partial shielding layer of the magnetic field located under the electromagnetic radiation recognition unit in which the magnetic powder is distributed; and
a geomagnetic sensor for detecting the magnetic field of the earth passing through a layer of partial shielding of the magnetic field. 2. The input device according to claim 1, in which a layer of partial shielding of the magnetic field is formed by mixing and applying a magnetic powder and adhesive. 3. The input device according to claim 1, in which the layer of partial shielding of the magnetic field has a density with a permeability of 100 ~ 200 μ0 in the direct current (DC) range. 4. The input device according to claim 1, in which the layer of partial shielding of the magnetic field has a thickness of 50 μm or more. 5. The input device according to claim 4, wherein said thickness varies with the permeability of the partial shielding layer of the magnetic field. 6. The input device according to claim 1, wherein the magnetic powder is a magnetic metal powder selected from the group,
consisting of ferrite, MolyPermalloy powder (MPP), Fe-Si-Al based material, and Ni-Fe based material. 7. The input device according to claim 6, in which a layer of partial shielding of the magnetic field is formed by mixing a magnetic metal powder and an amorphous metal powder with an adhesive. 8. The input device according to claim 1, in which a layer of partial shielding of the magnetic field is formed by applying electromagnetic radiation to the surface of the recognition unit. 9. The input device according to claim 1, further comprising a printed circuit board (PCB) unit located under a partial shielding layer of the magnetic field on which the geomagnetic sensor is located. 10. The input device according to claim 9, further comprising a shielding layer comprising a thin film of amorphous metal located below the partial shielding of the magnetic field, and preferably in proximity to the magnetic component, when the magnetic component is placed on or on the side of the PCB. 11. The input device of claim 10, wherein the partial shielding layer of the magnetic field is formed by applying electromagnetic radiation to the surface of the recognition unit, and the shielding layer containing a thin film of amorphous metal is placed on a portion of the partial shielding layer of the magnetic field. 12. An input device according to claim 10 or 11, in which the magnetic component comprises at least one of a speaker and a camera. 13. The input device according to claim 1, in which the layer of partial shielding of the magnetic field contains:
a magnetic powder shielding layer on which the magnetic powder is distributed to pass part of the earth's magnetic field; and
an amorphous metal shielding layer containing a thin film of amorphous metal to block the magnetic field. 14. The input device according to claim 13, in which the position of the shielding layer of the magnetic powder and the shielding layer containing a thin film of amorphous metal is different according to the position of the geomagnetic sensor. 15. The input device according to claim 13 or 14, in which the shielding layer of the magnetic powder is placed around the geomagnetic sensor, and the shielding layer containing a thin film of amorphous metal is placed in a region other than the region where the shielding layer of the magnetic powder is located.

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