Handwriting input device
By using multiple antennas in electromagnetic capacitive handwriting devices and controlling their reception methods, the problem of low sensitivity of existing devices is solved, and higher signal strength and input flexibility are achieved.
Patent Information
- Application Number
- CN202411419601.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-12
- Publication Date
- 2025-02-11
AI Technical Summary
The existing electromagnetic capacitive handwriting devices have low sensitivity and weak signals, resulting in inflexible and accurate inputs.
The signal strength and sensitivity are improved by using a plurality of first antennas and second antennas in the handwriting input device and by controlling the input unit, the first antenna group and the second antenna group receive signals simultaneously.
It improves the sensitivity of the handwriting input device and enhances the strength of the received signal, making the input more flexible and accurate.
Smart Images
Figure CN119414972A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of handwriting devices, and in particular to a handwriting input device. Background Art
[0002] Electromagnetic sensing technology has the characteristics of high resolution and not being easily affected by the outside world. It is currently being used more and more widely, and is widely used in various fields such as drawing boards, drawing screens, and embedded products.
[0003] In the existing electromagnetic capacitance handwriting device, an antenna board with a strip-shaped crossed antenna is used to realize capacitance input. When an electromagnetic pen with a resonant circuit is moved on the antenna board, electromagnetic waves are sent from the transmitting antenna of the antenna board to stimulate the resonant circuit of the electromagnetic pen, and then the electromagnetic pen returns the electromagnetic signal to the antenna board to realize electromagnetic input. However, the existing antenna board receives electromagnetic waves from a strip-shaped receiving antenna at a time, and the signal is weak, which will reduce the sensitivity of the electromagnetic capacitance handwriting device. Summary of the invention
[0004] In order to solve the technical problem of low sensitivity of the existing electromagnetic capacitance handwriting device, the present invention provides a handwriting input device with high sensitivity.
[0005] A handwriting input device has an electromagnetic receiving state, includes a plurality of first antennas and a control input unit, wherein the plurality of first antennas are arranged along a first direction, each of the first antennas includes a first end and a second end that are arranged opposite to each other, and when the handwriting input device is in the electromagnetic receiving state, is used to control the first end of the first antenna group as a receiving end, with the second end connected to a common end, and simultaneously control the second end of the second antenna group as a receiving end, with the first end connected to the common end, wherein the first antenna group is one or more of the plurality of first antennas, and the second antenna group is one or more of the plurality of first antennas.
[0006] Compared with the prior art, the control input unit of the handwriting input device provided by the present invention controls the first end of the first antenna group as a receiving end and the second end is connected to a common end, and controls the second end of the second antenna group as a receiving end and the first end is connected to a common end. The first antenna group and the second antenna group receive signals at the same time, thereby improving the strength of the received signal and improving the sensitivity of the handwriting input device. BRIEF DESCRIPTION OF THE DRAWINGS
[0007] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work, among which:
[0008] Figure 1 A connection diagram of a handwriting input device provided in an embodiment of the present invention;
[0009] Figure 2A for Figure 1 A schematic diagram of the structure of the antenna board shown;
[0010] Figure 2B for Figure 2A A schematic structural diagram of the first antenna shown;
[0011] Figure 2C for Figure 2A A schematic diagram of the structure of the second antenna shown;
[0012] Figure 3 for Figure 2A Another structural schematic diagram of the antenna shown;
[0013] Figure 4 for Figure 1 The state schematic diagram and equivalent circuit diagram of the first antenna when the handwriting input device is in the first electromagnetic emission state;
[0014] Figure 5A No finger touch Figure 1 The signal schematic diagram of the antenna board shown;
[0015] Figure 5B For finger touch Figure 1 The signal schematic diagram of the antenna board shown;
[0016] Figure 6 for Figure 1 The schematic diagram and equivalent circuit diagram of the antenna state when the handwriting input device is in the second electromagnetic emission state are shown. DETAILED DESCRIPTION
[0017] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0018] In the present invention, "at least one" means one or more, and "more than one" means two or more. The terms "first" and "second" are used only for descriptive purposes to distinguish objects such as substances from each other, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features.
[0019] See also Figure 1, is a connection diagram of a handwriting input device provided in an embodiment of the present invention. The handwriting input device 10 provided in an embodiment of the present invention may be a handwriting board or a handwriting screen, and the handwriting input device 10 includes an electrically connected antenna board 11 and a control input / output unit 13. Figure 2A , 2B and 2C, among which, Figure 2A for Figure 1 The schematic diagram of the structure of the antenna board shown in FIG. Figure 2B for Figure 2A The schematic diagram of the structure of the first antenna shown, Figure 2C for Figure 2A The schematic diagram of the structure of the second antenna is shown. The antenna board 11 includes a substrate 110, a plurality of first antennas 111 and a plurality of second antennas 112. The plurality of first antennas 111 are arranged on the substrate 110 along a first direction, and each of the first antennas 111 includes two opposite ends. The plurality of second antennas 112 are arranged on the substrate 110 along a second direction, and each of the second antennas 112 includes a first end and a second end opposite to each other. The first antenna 111 and the second antenna 112 are strip-shaped and insulated from each other, and the second direction intersects with the first direction, and are preferably perpendicular to each other.
[0020] The substrate 110 may be a transparent or opaque substrate, such as glass, epoxy resin glass fiber (FR4) or polyvinyl chloride (PVC). The first antenna 111 and the second antenna 112 may be configured as visible antennas or transparent antennas. Specifically, the visible antenna may be a metal wire, such as a copper wire. The transparent antenna may be a transparent antenna made of a transparent conductor, such as indium tin oxide (ITO), or a transparent antenna made of an opaque conductor, such as a mesh antenna made of metal wires such as copper, silver, and aluminum. The diameter of the metal wire is invisible to the naked eye. The shape of the mesh of the mesh antenna may be square, circular, elliptical, diamond, semicircular, polygonal, irregular, etc., without limitation. Figure 2A , 2B 2C shows a transparent antenna, which includes a plurality of rhombus-shaped units connected in series, two adjacent rhombus-shaped units are connected by vertices, and the grid of each rhombus-shaped unit is a rhombus. Figure 3 , showing a schematic diagram of another transparent antenna, the transparent antenna is overall rectangular and has a square grid.
[0021] In some embodiments, the control input / output unit 13 may be an ASIC integrated chip, and the antenna is connected to the endpoints of the ASIC integrated chip. When the number of the antennas is greater than twice the endpoints of the ASIC integrated chip, two ASIC integrated chips may be used to work synchronously to expand the connection endpoints.
[0022] In this embodiment, the handwriting input device 10 has a first electromagnetic emitting state and a first electromagnetic receiving state. When the handwriting input device 10 is in the first electromagnetic emitting state, Figure 4 As shown, the control input / output unit 13 controls the first end of the first antenna group as a transmitting end, and the second end of the first antenna group is connected to a common end, and at the same time controls the second end of the second antenna group as a transmitting end, and the first end of the second antenna group is connected to a common end, the first antenna group is one or more of the multiple first antennas 111, and the second antenna group is one or more of the multiple first antennas 111.
[0023] In some embodiments, the first antenna group includes a plurality of continuous first antennas arranged along a first direction, and the second antenna group includes a plurality of continuous first antennas arranged along the first direction; along the first direction, there is no first antenna between the first antenna group and the second antenna group.
[0024] In some embodiments, the first antenna group includes a plurality of continuous first antennas arranged along a first direction, and the second antenna group includes a plurality of continuous first antennas arranged along the first direction; along the first direction, at least one of the first antennas is spaced between the first antenna group and the second antenna group.
[0025] It is understood that the grounding can be used as a common terminal.
[0026] The first end and the second end are two opposite ends of the first antenna 111, and the first ends of all the first antennas 111 are located at the same end of the substrate 110, and the second ends of all the first antennas 111 are located at another opposite same end of the substrate 110. The first end of the first antenna group serves as a transmitting end, that is, the first ends of the continuous plurality of first antennas 111 of the first antenna group simultaneously serve as transmitting ends, and a transmission signal is input to generate a current flowing from the first ends of the plurality of first antennas 111 of the first antenna group to the second ends. The second end of the second antenna group serves as a transmitting end, that is, the second ends of the continuous plurality of first antennas 111 of the second antenna group simultaneously serve as transmitting ends, and a transmission signal is input to generate a current flowing from the second ends of the plurality of first antennas 111 of the second antenna group to the first end.
[0027] At this time, the first antenna group and the second antenna group both transmit signals to the electromagnetic pen, and the circuit equivalent diagram is as follows: Figure 4As shown, the currents of the first antenna group and the second antenna group flow to the common end. According to Ampere's right-hand rule, the magnetic field generated by the currents of the first antenna group and the second antenna group is inward, the magnetic fields between the first antenna group and the second antenna group are added, and the magnetic fields outside the first antenna group and the second antenna group are subtracted. When the handwriting input device 10 is in the first electromagnetic receiving state, the control input / output unit 13 controls the first end of the first antenna group as the receiving end, and the second end is connected to the common end, and controls the second end of the second antenna group as the receiving end, and the first end is connected to the common end.
[0028] When the handwriting input device 10 alternates between the first electromagnetic transmitting state and the first electromagnetic receiving state, the handwriting input device 10 is in the first electromagnetic mode, the first antenna 111 senses the coordinates of the electromagnetic pen in the first direction, and the second antenna 112 senses the coordinates of the electromagnetic pen in the second direction, so that the two-dimensional coordinates of the electromagnetic pen can be confirmed, thereby realizing electromagnetic input.
[0029] For easier understanding, an example is given here to explain in detail. Figure 4 The first antennas 111 are antennas X1 to X N , are arranged in parallel on the substrate 110 with equal spacing D. The first antenna group is X1 to X3, and the second antenna group is X6 to X8. According to the Biot-Savart Law: Where B is the magnetic field intensity and μ0 is the vacuum magnetic permeability, which is 4π×10 -7 T·m·A -1 , i is the current of the antenna, r is the distance from the antenna to the electromagnetic pen. When the electromagnetic pen writes at the center of antenna X3 and antenna X6, the distance between antenna X3, X6 and the electromagnetic pen is r3=3D / 2, and the magnetic field strength generated is B3=m. The distance between antenna X2, X7 and the electromagnetic pen is r2=5D / 2, and the magnetic field generated is The distance between the antenna X1 and the electromagnetic pen X8 is r1 = 7D / 2, and the magnetic field generated At this time, the magnetic field strength at the electromagnetic pen is B0 = 2 × (m + 0.6m + 0.43m) = 4.06m. It can be seen that the signal received by the electromagnetic pen is three times stronger than the signal transmitted by one antenna. When the handwriting input device 10 receives the signal, the signal received by the electromagnetic pen is enhanced, and the electromagnetic signal fed back by the electromagnetic pen received by the first antenna group and the first antenna group is also proportional to the signal strength received by the electromagnetic pen. The coordinates of the electromagnetic pen can be confirmed based on the relationship between the strength of the electromagnetic signal fed back by the electromagnetic pen received by the first antenna group and the first antenna group and the distance from the electromagnetic pen to the antenna.
[0030] Compared with the prior art, the control input unit 13 of the handwriting input device 10 provided by the present invention controls the first end of the first antenna group as a transmitting end, and the second end of the first antenna group is connected to a common end, and controls the second end of the second antenna group as a transmitting end, and the first end of the second antenna group is connected to a common end. The magnetic fields of the first antenna group and the second antenna group are added, which can enhance the strength of the transmitted signal and improve the strength of the received electromagnetic signal. The first antenna group and the second antenna group receive signals at the same time, which can improve the strength of the received signal, improve the sensitivity of the handwriting input device, and improve the sensitivity of the handwriting input device 10.
[0031] In a further embodiment, the handwriting input device 10 has a capacitive input state. When the handwriting input device 10 is in the capacitive input state, the control input / output unit 13 is used to control one end of the fifth antenna group as a transmitting end, and the other end of the fifth antenna group is open, and at the same time control one end of the sixth antenna group as a receiving end, and the other end of the sixth antenna group is open, wherein the fifth antenna group is one of the multiple first antennas, and the sixth antenna group is one or more of the multiple second antennas.
[0032] In some embodiments, the sixth antenna group is a plurality of consecutive second antennas arranged along the second direction.
[0033] It should be noted that an open circuit can also be achieved by setting a high resistance.
[0034] When the handwriting input device 10 is in the capacitive input state, the first antenna 111 and the second antenna 112 are cross-coupled, the fifth antenna group transmits signals synchronously with the sixth antenna group receives signals, and the handwriting input device 10 is in the capacitive mode. The first antenna 111 senses the coordinates of the finger or capacitive pen in the first direction, and the second antenna 112 senses the coordinates of the finger or capacitive pen in the second direction, and the two-dimensional coordinates of the finger or capacitive pen can be confirmed, thereby realizing capacitive input. For details, please refer to Figure 5A and 5B ,in, Figure 5A No finger touch Figure 2A The signal diagram of the antenna board shown, Figure 5B For finger touch Figure 2A When a finger or a capacitive pen touches the sixth antenna group, the signal emitted by the fifth antenna group is introduced into the human body, and the signal received by the sixth antenna group becomes weaker. Based on the different transmission and reception coordination of the first antenna 111 and the second antenna 112, the touch position of the finger or the capacitive pen can be confirmed according to the energy of the signal received by the sixth antenna group at different positions.
[0035] Compared with the prior art, the handwriting input device 10 provided by the present invention is provided with a control input unit 13 which controls the first end of the first antenna group as a transmitting end, and the second end of the first antenna group is connected to a common end, and controls the second end of the second antenna group as a transmitting end, and the first end of the second antenna group is connected to a common end. The magnetic fields of the first antenna group and the second antenna group are added, so that the strength of the transmitted signal can be enhanced, and the strength of the received electromagnetic signal can be improved. The first antenna group and the second antenna group receive signals at the same time, so that the strength of the received signal can be improved, and electromagnetic input and capacitive input can be realized at the same time without reducing the sensitivity of the electromagnetic input.
[0036] In some embodiments, the handwriting input device 10 has a second electromagnetic emitting state and a second electromagnetic receiving state. When the handwriting input device 10 is in the second electromagnetic emitting state, Figure 6 As shown, the control input / output unit 13 controls the first end of the first antenna group as a transmitting end, and the second end of the first antenna group is connected to a common end; at the same time, the second end of the second antenna group is controlled as a transmitting end, and the first end of the second antenna group is connected to a common end; at the same time, the third end of the third antenna group is controlled as a transmitting end, and the fourth end of the third antenna group is connected to a common end; at the same time, the fourth end of the fourth antenna group is controlled as a transmitting end, and the third end of the fourth antenna group is controlled to be connected to a common end, so that the antenna current corresponding to the closed pattern formed by the first antenna group, the second antenna group, the third antenna group and the fourth antenna group projected on the operation surface flows in a clockwise direction or a counterclockwise direction, wherein the third antenna group is one or more of the multiple second antennas 112, and the fourth antenna group is one or more of the multiple second antennas 112.
[0037] In some embodiments, the third antenna group includes a plurality of second antennas arranged in a second direction, and the fourth antenna group includes a plurality of second antennas arranged in a second direction; along the second direction, there is no second antenna between the third antenna group and the fourth antenna group.
[0038] In some embodiments, the third antenna group includes a plurality of continuous second antennas arranged along a second direction, and the fourth antenna group includes a plurality of continuous second antennas arranged along the second direction; along the second direction, at least one of the second antennas is spaced between the third antenna group and the fourth antenna group.
[0039] It can be understood that the operating surface refers to the writing surface of the electromagnetic pen on the handwriting input device 10 .
[0040] The first end and the second end are two opposite ends of the first antenna 111, located at a pair of opposite ends of the substrate 110. The first end of the first antenna group is used as a transmitting end, generating a current flowing from the first ends of the multiple first antennas 111 of the first antenna group to the second end; the second end of the second antenna group is used as a transmitting end, generating a current flowing from the second ends of the multiple first antennas 111 of the second antenna group to the first end. The third end and the fourth end are two opposite ends of the second antenna 112, located at another pair of opposite ends of the substrate 110. The third end of the third antenna group is used as a transmitting end, generating a current flowing from the third ends of the multiple second antennas 112 of the third antenna group to the fourth end; the fourth end of the fourth antenna group is used as a transmitting end, generating a current flowing from the fourth ends of the multiple second antennas 112 of the fourth antenna group to the third end. The currents in four directions form a quadrilateral.
[0041] At this time, the first antenna group, the second antenna group, the third antenna group and the fourth antenna group all transmit signals to the electromagnetic pen, and the circuit equivalent diagram thereof is as follows: Figure 6 As shown, the magnetic fields of the first antenna group, the second antenna group, the third antenna group and the fourth antenna group are added, and the magnetic fields outside the first antenna group, the second antenna group, the third antenna group and the fourth antenna group are subtracted.
[0042] When the handwriting input device 10 is in the second electromagnetic receiving state, the control input / output unit 13 controls the first end of the first antenna group as a receiving end, the second end is connected to the common end, and the second end of the second antenna group is controlled as a receiving end, the first end is connected to the common end, and the third end of the third antenna group is controlled as a receiving end, the fourth end is connected to the common end, and the fourth end of the fourth antenna group is controlled as a receiving end, the third end is connected to the common end, so that the antenna current corresponding to the closed pattern formed by the first antenna group, the second antenna group, the third antenna group and the fourth antenna group projected on the operation surface flows in a clockwise direction or a counterclockwise direction. When the handwriting input device 10 alternates between the second electromagnetic transmitting state and the second electromagnetic receiving state, the handwriting input device 10 is in the second electromagnetic mode, the first antenna 111 senses the coordinates of the electromagnetic pen in the first direction, and the second antenna 112 senses the coordinates of the electromagnetic pen in the second direction, so that the two-dimensional coordinates of the electromagnetic pen can be confirmed, thereby realizing electromagnetic input.
[0043] For easier understanding, an example is given here to explain in detail. Figure 6 The first antennas 111 are antennas X1 to X N , are arranged in parallel on the substrate 110 at equal intervals D, and the plurality of second antennas 112 are antennas Y1 to Y N, arranged in parallel to the substrate 110 with equal spacing D. The first antenna group is antennas X1 to X3, the second antenna group is antennas X6 to X8, the third antenna group is antennas Y1 to Y3, and the second antenna group is antennas Y6 to Y8. According to the Biot-Savart law, when the electromagnetic pen writes at the center of antennas X3, X6, Y6 and Y8, the magnetic field strength generated by the antennas is shown in the following table:
[0044]
[0045] It should be noted that, in some embodiments, the handwriting input device 10 may be configured to have only the first electromagnetic mode.
[0046] In some embodiments, the handwriting input device 10 can be configured to have a first electromagnetic mode and a capacitive mode, and a specific switching mode can be configured as required.
[0047] In some embodiments, the handwriting input device 10 may be configured to have only the second electromagnetic mode.
[0048] In some embodiments, the handwriting input device 10 can be configured to have a second electromagnetic mode and a capacitive mode, and a specific switching mode can be set as required.
[0049] In some embodiments, the handwriting input device 10 may be configured to have a first electromagnetic mode and a second electromagnetic mode, and a specific switching mode may be configured as required.
[0050] In some embodiments, the handwriting input device 10 can be configured to have a first electromagnetic mode, a second electromagnetic mode, and a capacitive mode, and a specific switching mode can be configured as required.
[0051] Compared with the prior art, the control input unit 13 of the handwriting input device 10 provided by the present invention controls the first end of the first antenna group as a transmitting end, the second end of the first antenna group is connected to the common end, and the second end of the second antenna group is controlled as a transmitting end, the first end of the second antenna group is connected to the common end, and the third end of the third antenna group is controlled as a transmitting end, the fourth end of the third antenna group is connected to the common end, and the fourth end of the fourth antenna group is controlled as a transmitting end, and the third end of the fourth antenna group is controlled to be connected to the common end. The magnetic fields of the first antenna group, the second antenna group, the third antenna group, and the fourth antenna group are added together, so that the strength of the transmitted signal can be enhanced, and the strength of the received electromagnetic signal can be improved. The first antenna group, the second antenna group, the third antenna group, and the fourth antenna group receive signals at the same time, so that the strength of the received signal can be improved, and the sensitivity of the handwriting input device 10 can be further improved. In addition, the first antenna 111 and the second antenna 112 can simultaneously receive the electromagnetic signal fed back by the electromagnetic pen, thereby improving the scanning efficiency and the speed of confirming the two-dimensional coordinates of the electromagnetic pen.
[0052] The above descriptions are only some embodiments of the present invention, and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.
Claims
1. A handwriting input device having an electromagnetic receiving state, characterized in that: include: A plurality of first antennas arranged along a first direction, each of the first antennas comprising a first end and a second end arranged opposite to each other; A control input / output unit is used to control the first end of the first antenna group as a receiving end and the second end connected to a common end when the handwriting input device is in the electromagnetic receiving state, and to control the second end of the second antenna group as a receiving end and the first end connected to a common end, when the handwriting input device is in the electromagnetic receiving state. The first antenna group is one or more of the multiple first antennas, and the second antenna group is one or more of the multiple first antennas.
2. The handwriting input device according to claim 1, characterized in that: When the handwriting input device has an electromagnetic emission state, when the handwriting input device is in the electromagnetic emission state, the control input / output unit controls the first end of the first antenna group as the emission end and the second end is connected to the common end, and at the same time controls the second end of the second antenna group as the emission end and the first end is connected to the common end.
3. The handwriting input device according to claim 1, characterized in that: The first antenna group includes a plurality of first antennas arranged continuously along the first direction, and the second antenna group includes a plurality of first antennas arranged continuously along the first direction; Along the first direction, the first antenna does not exist between the first antenna group and the second antenna group.
4. The handwriting input device according to claim 1, characterized in that: The first antenna group includes a plurality of first antennas arranged continuously along the first direction, and the second antenna group includes a plurality of first antennas arranged continuously along the first direction; Along the first direction, at least one of the first antennas is spaced between the first antenna group and the second antenna group.
5. The handwriting input device according to claim 1, characterized in that: The handwriting input device also includes a plurality of second antennas arranged along a second direction, the second direction intersecting the first direction, each of the first antennas includes a third end and a fourth end arranged opposite to each other, and when the handwriting input device is in the electromagnetic receiving state, the control input / output unit is further used to simultaneously control the third end of the third antenna group as a receiving end, and the fourth end is connected to a common end, and simultaneously control the fourth end of the fourth antenna group as a receiving end, and the third end is connected to a common end, so that the antenna current corresponding to the closed pattern formed by the first antenna group, the second antenna group, the third antenna group and the fourth antenna group projected on the operation surface flows in a clockwise direction or a counterclockwise direction, wherein the third antenna group is one of the plurality of second antennas or a plurality of continuous antennas arranged along the second direction, and the fourth antenna group is one of the plurality of second antennas or a plurality of continuous antennas arranged along the second direction.
6. The handwriting input device according to claim 2, characterized in that: The handwriting input device also includes a plurality of second antennas arranged along a second direction, the second direction intersecting the first direction, each of the second antennas includes a third end and a fourth end arranged opposite to each other, when the handwriting input device is in the electromagnetic transmission state, the control input / output unit controls the third end of the third antenna group as the transmitting end, and the fourth end is connected to the common end, and at the same time controls the fourth end of the fourth antenna group as the transmitting end, and the third end is connected to the common end, so that the antenna current corresponding to the closed pattern formed by the first antenna group, the second antenna group, the third antenna group and the fourth antenna group projected on the operation surface flows in a clockwise direction or a counterclockwise direction, the third antenna group is one or more of the plurality of second antennas, and the fourth antenna group is one or more of the plurality of second antennas.
7. The handwriting input device according to claim 5 or 6, characterized in that: The third antenna group includes a plurality of second antennas arranged continuously along the second direction, and the fourth antenna group includes a plurality of second antennas arranged continuously along the second direction; Along the second direction, the second antenna does not exist between the third antenna group and the fourth antenna group.
8. The handwriting input device according to claim 5 or 6, characterized in that: The third antenna group includes a plurality of second antennas arranged continuously along the second direction, and the fourth antenna group includes a plurality of second antennas arranged continuously along the second direction; Along the second direction, at least one of the second antennas is spaced between the third antenna group and the fourth antenna group.
9. The handwriting input device according to any one of claims 1 to 6, characterized in that: The handwriting input device further comprises a plurality of second antennas arranged along a second direction, the second direction intersecting the first direction, each of the second antennas comprises a third end and a fourth end arranged opposite to each other, the plurality of first antennas comprises a fifth antenna group; the plurality of second antennas comprises a sixth antenna group, the handwriting input device has a capacitive input state, when the handwriting input device is in the capacitive input state, the control input / output unit controls the first end of the fifth antenna group as a transmitting end, and the second end is open circuit; And the third end of the sixth antenna group is controlled to be a receiving end, and the fourth end is open.
10. The handwriting input device according to claim 9, characterized in that: The first antenna is a mesh antenna, the sixth antenna group is a plurality of consecutive second antennas arranged along the second direction, and the fifth antenna group is a single first antenna.