Handwriting input device and handwriting input method

Abstract

The invention relates to the technical field of handwriting devices, in particular to handwriting input equipment and a handwriting input method. The handwriting input device comprises a sensing unit and a control unit, the sensing unit comprises a plurality of antennas arranged in a queue, each antenna comprises a first end and a second end which are opposite, the control unit comprises a first control unit and a second control unit which are in communication connection, the first control unit comprises a first matrix switch, and the second control unit comprises a second matrix switch. The first control unit comprises a first matrix switch which is electrically connected with the first end, and the second control unit comprises a second matrix switch which is electrically connected with the second end. According to the handwriting input device, the first control unit and the second control unit which are in communication connection are arranged, the first matrix switch and the second matrix switch are used for controlling the first end and the second end of the antenna respectively, the antenna can be a strip-shaped antenna, and the single antenna is simple in wiring, easy to manufacture and low in cost.

Description

Technical Field

[0001] The present invention relates to the technical field of handwriting devices, and in particular to a handwriting input device and a handwriting input method. 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 handwriting device, when an electromagnetic pen with a resonant circuit is moved on the antenna board of the electromagnetic board, the electromagnetic wave sent from the transmitting coil of the antenna board excites the resonant circuit of the electromagnetic pen, so that the electromagnetic pen returns an electromagnetic signal to the antenna board. The antenna board uses a ring coil as an antenna to send or receive electromagnetic signals. The ring antennas of the existing electromagnetic handwriting device are nested and arranged with a predetermined width, such as Figure 1 As shown, the wiring is complicated and the manufacturing is inconvenient. Summary of the invention

[0004] In order to solve the technical problems of complex antenna wiring and inconvenient manufacturing of the electromagnetic handwriting device, the present invention provides a handwriting input device and a handwriting input method.

[0005] A handwriting input device includes a sensing unit and a control unit, wherein the sensing unit includes a plurality of antennas arranged in a queue, each of the antennas includes a first end and a second end opposite to each other, the control unit includes a first control unit and a second control unit in communication connection, the first control unit includes a first matrix switch, the first matrix switch is electrically connected to the first end, and the second control unit includes a second matrix switch, the second matrix switch is electrically connected to the second end.

[0006] In some embodiments, the antenna is a strip antenna and a transparent antenna.

[0007] In some embodiments, the sensing unit has a transmitting state, and the first control unit is used to control the first end of the first antenna as a transmitting end through the first matrix switch, control the first end of the second antenna to be connected to a common reference end, and send a first synchronization signal; the second control unit is used to control the second end of the first antenna to be connected to the common reference end through the second matrix switch according to the first synchronization signal, and control the second end of the second antenna to be a transmitting end, wherein the first antenna and the second antenna are any two different ones of the multiple antennas.

[0008] In some embodiments, the first antenna and the second antenna are separated by at least two antennas.

[0009] In some embodiments, the handwriting input device also includes a differential amplifier, the number of antennas is a, the first matrix switch includes at least a*b first analog switches, each of the antennas is electrically connected to the first matrix switch to form b first signal channels, at least one of the first signal channels is connected to the first input terminal of the differential amplifier, and at least one of the first signal channels is connected to the second input terminal of the differential amplifier, wherein a≥2, b≥2, and a and b are integers.

[0010] In some embodiments, the sensing unit has a receiving state, and the first control unit is used to control the first end of the third antenna to be connected to the first input end of the differential amplifier, control the first end of the fourth antenna to be connected to the second input end of the differential amplifier, and send a second synchronization signal through the first matrix switch; the second control unit is used to control the second end of the third antenna to be connected to a common reference end through the second matrix switch according to the second synchronization signal, and control the second end of the fourth antenna to be connected to a common reference end, wherein the third antenna and the fourth antenna are any two different antennas among the multiple antennas.

[0011] In some embodiments, the sensing unit has a receiving state, and the first control unit is used to control the first end of the third antenna to be connected to the first input end of the differential amplifier through the first matrix switch, control the first end of the fourth antenna to be connected to a common reference end, and send a second synchronization signal; the second control unit is used to control the second end of the third antenna to be connected to the common reference end through the second matrix switch according to the second synchronization signal, and control the second end of the fourth antenna to be connected to the second input end of the differential amplifier, wherein the third antenna and the fourth antenna are any two different antennas among the multiple antennas.

[0012] In some embodiments, the sensing unit includes a first sensing unit and a second sensing unit, the antenna of the first sensing unit and the antenna of the second sensing unit are arranged crosswise, the handwriting input device has a capacitive mode, the first control unit is used to control the first end of the antenna of the first sensing unit as a transmitting end through the first matrix switch, control the first end of the antenna of the second sensing unit to be connected to the first input end of the differential amplifier, the second input end of the differential amplifier is connected to a common reference end, and send a third synchronization signal, the second control unit is used to control the second end of the antenna of the first sensing unit to be set to high impedance through the second matrix switch according to the third synchronization signal, and control the second end of the antenna of the second sensing unit to be set to high impedance.

[0013] A handwriting input method, comprising:

[0014] Providing a sensing unit, the sensing unit comprising a plurality of antennas arranged in a queue, each of the antennas comprising a first end and a second end opposite to each other;

[0015] Providing a first control unit, the first control unit controls the first end of the first antenna to serve as a transmitting end, controls the first end of the second antenna to be connected to a common reference end, and transmits a first synchronization signal, wherein the first antenna and the second antenna are any two different antennas among the plurality of antennas;

[0016] A second control unit is provided that is communicatively connected to the first control unit. The second control unit controls the second end of the first antenna to be connected to a common reference end according to the first synchronization signal, and controls the second end of the second antenna to be used as a transmitting end.

[0017] In some embodiments, it also includes:

[0018] A differential amplifier is provided, wherein the first control unit controls the first end of the third antenna to be connected to the first input end of the differential amplifier, controls the first end of the fourth antenna to be connected to the common reference end, and sends a second synchronization signal, wherein the third antenna and the fourth antenna are any two different antennas among the plurality of antennas;

[0019] The second control unit controls the second end of the third antenna to be connected to a common reference end and controls the second end of the fourth antenna to be connected to a second input end of the differential amplifier through the second matrix switch according to the second synchronization signal.

[0020] Compared with the prior art, the handwriting input device provided by the present invention is provided with the first control unit and the second control unit which are communicatively connected, and the first end and the second end of the antenna are controlled respectively by the first matrix switch and the second matrix switch, so that the antenna can adopt a strip antenna, and a loop antenna can be formed by selecting two antennas. The wiring of a single strip antenna is simple, the manufacturing is simple, and the cost is low; the first control unit and the second control unit which are communicatively connected can synchronously control the two antennas to transmit signals respectively and simultaneously, and a stronger transmission signal can be obtained. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] 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:

[0022] Figure 1A schematic diagram of the arrangement of a loop antenna of an existing electromagnetic handwriting device in the prior art;

[0023] Figure 2 A connection diagram of a handwriting input device provided in an embodiment of the present invention;

[0024] Figure 3 for Figure 2 The schematic diagram of the connection between the sensing unit and the differential amplifier is shown;

[0025] Figure 4 for Figure 3 The connection diagram of the antenna and the analog switch is shown;

[0026] Figure 5 for Figure 3 The equivalent connection diagram of the sensing unit and the differential amplifier is shown;

[0027] Fig. 6A , 6B They are Figure 3 The schematic diagram of the state of the sensing unit shown is in the transmitting state and the receiving state;

[0028] Figure 7 for Fig. 6A The circuit equivalent diagram of the first antenna and the second antenna transmitting signals simultaneously;

[0029] Fig. 8A , 8B and 8C Figure 3 Another structural schematic diagram of the antenna shown;

[0030] Fig. 9 A schematic diagram of a flow chart of a handwriting input method provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0031] 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.

[0032] 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.

[0033] See also Figure 2 , Figure 3 and Figure 4 ,in, Figure 2A connection diagram of a handwriting input device provided in an embodiment of the present invention, Figure 3 FIG2 is a schematic diagram of the connection between the sensing unit and the differential amplifier. Figure 4 for Figure 3 The handwriting input device 10 includes a sensing unit 11, a control unit and a differential amplifier 15. The sensing unit 11 includes a plurality of antennas 111 arranged in a queue, each of the antennas 111 includes a first end 1111 and a second end 1112 opposite to each other, the control unit includes a first control unit 12 and a second control unit 13 in communication connection, the first control unit 12 includes a first matrix switch 121, the first matrix switch 121 is electrically connected to the first end 1111, the second control unit 13 includes a second matrix switch 131, the second matrix switch 131 is electrically connected to the second end 1112.

[0034] The number of the antennas 111 is a, the first matrix switch 121 includes at least a*b first analog switches 1211, the first end 1111 of each antenna 111 is electrically connected to the first matrix switch 121 to form b first signal channels 120, at least one of the first signal channels 120 is connected to the first input end of the differential amplifier 15, and at least one of the first signal channels 120 is connected to the second input end of the differential amplifier 15, wherein a≥2, b≥2, and a and b are integers. The second matrix switch 131 includes at least a*c second analog switches 1311, the second end 1112 of each antenna 111 is electrically connected to the second matrix switch 131 to form c second signal channels 130, wherein c≥2, and c is an integer.

[0035] The first control unit 12 can select the first end 1111 of the antenna 111 by controlling the opening and closing of the first analog switch 1211, and the second control unit 13 can select the second end 1112 of the antenna 111 by controlling the opening and closing of the second analog switch 1311. The first control unit 12 and the second control unit 13 can select multiple antennas 111 to transmit signals at the same time to enhance the transmission signal. Two antennas 111 can be selected to form a closed loop antenna to sense the electromagnetic signal sent by the electromagnetic pen, and one antenna 111 is connected to the first input end of the differential amplifier 15 through the first signal channel 120, and the other antenna 111 is connected to the second input end of the differential amplifier 15 through the first signal channel 120 to form a differential input to enhance the received signal.

[0036] It is understandable that those skilled in the art can set a specific connection mode between the first signal channel 120 and the differential amplifier 15 according to actual needs. Figure 5 A specific connection example is shown, in which the number of the differential amplifiers 15 is the same as the number of the first signal channels 120, and in two adjacent first signal channels 120, one first signal channel 120 is connected to the first input terminal of one differential amplifier 15, the second input terminal of the differential amplifier 15 is connected to the common reference terminal through a first switch S1, and is connected to another first signal channel 120 through a second switch S2, and at the same time, the other first signal channel 120 is connected to the second input terminal of another differential amplifier 15 through a third switch S3.

[0037] The sensing unit 11 has a transmitting state and a receiving state. The first control unit 12 and the second control unit 13 control the sensing unit 11 to be in the transmitting state. Specifically, the first control unit 12 controls the first end 1111 of the first antenna to be used as a transmitting end through the first matrix switch 121, controls the first end 1111 of the second antenna to be connected to a common reference end, and sends a first synchronization signal; the second control unit 13 is used to control the second end 1112 of the first antenna to be connected to the common reference end through the second matrix switch 131 according to the first synchronization signal, and controls the second end 1112 of the second antenna to be used as a transmitting end, so that the sensing unit 11 is in the transmitting state, as shown in FIG. Fig. 6A The first antenna and the second antenna are any two different antennas among the plurality of antennas 111 .

[0038] At this time, the first antenna and the second antenna both transmit signals to the electromagnetic pen, and the circuit equivalent diagram is as follows: Figure 7 As shown, the magnetic field directions of the first antenna and the second antenna point between the first antenna and the second antenna, the magnetic fields between the first antenna and the second antenna are superimposed, the signal is enhanced, and the magnetic fields outside the first antenna and the second antenna are subtracted. Preferably, when the first antenna and the second antenna transmit signals, the first antenna and the second antenna are separated by at least two antennas 111.

[0039] It can be understood that the first control unit 12 can select multiple first antennas at the same time, and the second control unit 13 can select multiple second antennas at the same time.

[0040] The first control unit 12 and the second control unit 13 control the sensing unit 11 to be in a receiving state. Specifically, the first control unit 12 controls the first end 1111 of the third antenna to be connected to the first input end of the differential amplifier 15 through the first matrix switch 121, controls the first end 1111 of the fourth antenna to be connected to the second input end of the differential amplifier 15, and sends a second synchronization signal; the second control unit 13 controls the second end 1112 of the third antenna to be connected to a common reference end through the second matrix switch 131 according to the second synchronization signal, and controls the second end 1112 of the fourth antenna to be connected to the common reference end, so that the sensing unit 11 is in a receiving state, as shown in FIG. Figure 6B The third antenna and the fourth antenna are any two different antennas among the plurality of antennas 111 .

[0041] At this time, the third antenna and the fourth antenna form a closed loop antenna to sense the electromagnetic signal fed back by the electromagnetic pen, the second ends 1112 of the third antenna and the fourth antenna are connected through the second signal channel 130, the first end 1111 of the first antenna is connected to the first input end of the differential amplifier 15 through the first signal channel 120, and the first end 1111 of the second antenna is connected to the second input end of the differential amplifier 15 through the first signal channel 120 to form a differential input.

[0042] It can be understood that when the ground point is used as the common reference point, the connection to the common reference terminal is grounding.

[0043] It can also be understood that the first control unit 12 can select multiple first antennas at the same time, and the second control unit 13 can select multiple second antennas at the same time. Here, a specific example is used for explanation. Figure 3, set a=10, the first ends 1111 of the 10 antennas 111 are antenna ends T0~T9 respectively, and the second ends 1112 are antenna ends S0~S9 respectively; b=8, the 8 first signal channels 120 are signal channels A0~A7 respectively, signal channels A0 and A1 are respectively connected to the two input ends of the differential amplifier 15, signal channels A2 and A3 are respectively connected to the two input ends of the differential amplifier 15, signal channels A4 and A5 are respectively connected to the two input ends of the differential amplifier 15, signal channels A6 and A7 are respectively connected to the two input ends of the differential amplifier 15, and the number of the first analog switches 1211 is 10*8; c=10, the 10 second signal channels 130 are respectively signal channels B0~B7, and the number of the second analog switches 1311 is 10*8. If a T0-T1 antenna loop needs to be formed, the first analog switch A1T0 can be enabled to connect the antenna terminal T0 and the signal channel A1, and the first analog switch A0T1 can be enabled to connect the antenna terminal T1 and the signal channel A0; the second analog switch B1S0 can be enabled to connect the antenna terminal S0 and the signal channel B1, and the second analog switch B0S1 can be enabled to connect the antenna terminal S1 and the signal channel B0. The two antennas 111 can form a closed loop antenna to receive electromagnetic signals and sense the stylus writing on the T0-T1 antenna.

[0044] It is understandable that the antenna end T0 and the antenna end T1 may also select other first signal channels 120 to be turned on to form an antenna loop. Of course, alternate antennas may also be selected to form an antenna loop, such as a T0-T3 antenna loop, a T1-T4 antenna loop, a T2-T5 antenna loop, and a T6-T9 antenna loop. It can be seen that since b=8, at most four antenna loops can be formed simultaneously.

[0045] It is understandable that by simultaneously selecting a plurality of antennas 111 to form a closed loop antenna in pairs, and respectively connecting the two input terminals of the differential amplifier 15 to form a differential input, the scanning efficiency can be improved.

[0046] It should be noted that, in this embodiment, a differential input is formed by connecting the first end 1111 of the third antenna and the first end 1111 of the fourth antenna to the differential amplifier 15, that is, the ends of the third antenna and the fourth antenna on the same side are connected to the differential amplifier 15. In other embodiments, those skilled in the art may also configure such that the ends of the third antenna and the fourth antenna on different sides are connected to the differential amplifier, for example, the first control unit controls the first end of the third antenna to be connected to the first input end of the differential amplifier through the first matrix switch, controls the first end of the fourth antenna to be connected to the common reference end, and sends a second synchronization signal; the second control unit controls the second end of the third antenna to be connected to the common reference end through the second matrix switch according to the second synchronization signal, and controls the second end of the fourth antenna to be connected to the second input end of the differential amplifier, wherein the third antenna and the fourth antenna are any two different antennas among the plurality of antennas.

[0047] It is also necessary to refer to Fig. 6A and 6B The first control unit 12 is arranged on a chip, such as a system on chip (SOC chip), and the second control unit 13 can be arranged on another chip. The two chips are connected through a serial port, such as a serial peripheral interface (SPI), and the first control unit 12 and the second control unit 13 are synchronized by transmitting the synchronization signal through a numerically controlled oscillator (NCO).

[0048] The sensing unit 11 includes a first sensing unit and a second sensing unit. The antenna 111 of the first sensing unit is arranged along a first direction, and the antenna 111 of the second sensing unit is arranged along a second direction. The angle between the first direction and the second direction is non-zero. The first sensing unit senses the coordinates of the stylus in the first direction, and the second sensing unit senses the coordinates of the stylus in the second direction, thereby confirming the two-dimensional coordinates of the stylus. Preferably, the first direction and the second direction are perpendicular to each other.

[0049] In a further embodiment, the first signal channel 120 and the second signal channel 130 are also used to transmit capacitance signals, and the handwriting input device 10 has an electromagnetic mode and a capacitance mode. In the electromagnetic mode, the first sensing unit senses the coordinates of the electromagnetic pen in the first direction, and the second sensing unit senses the coordinates of the stylus in the second direction, thereby confirming the two-dimensional coordinates of the electromagnetic pen. In the capacitance mode, the first sensing unit and the second sensing unit are cross-coupled, the first sensing unit confirms the coordinates of the finger or the capacitance pen in the first direction, and the second sensing unit confirms the coordinates of the finger or the capacitance pen in the second direction, thereby confirming the two-dimensional coordinates of the finger or the capacitance pen.

[0050] When the handwriting input device 10 is in the electromagnetic mode, the sensing unit 11 alternates between the transmitting state and the receiving state. The specific transmitting and receiving methods in the electromagnetic mode have been described above and will not be repeated here.

[0051] When the handwriting input device 10 is in the capacitive mode, the sensing unit 11 is in the transmitting state and the receiving state at the same time, that is, the first sensing unit is in the transmitting state, and the second sensing unit is in the receiving state.

[0052] Specifically, the first control unit 12 controls the first end 1111 of the antenna 111 of the first sensing unit as a transmitting end through the first matrix switch 121, controls the first end 1111 of the antenna 111 of the second sensing unit to be connected to the first input end of the differential amplifier 15, the second input end of the differential amplifier 15 is connected to the common reference end, and sends a third synchronization signal. The second control unit 13 controls the second end 1112 of the antenna 111 of the first sensing unit to be set to high impedance through the second matrix switch 131 according to the third synchronization signal, and controls the second end 1112 of the antenna 111 of the second sensing unit to be set to high impedance, so that the first sensing unit is in a transmitting state and the second sensing unit is in a receiving state. The first end 1111 of the first antenna of the second sensing unit is connected to the first input end of the differential amplifier 15, and the second input end of the differential amplifier 15 is connected to the common reference end to form a differential input.

[0053] At this time, the first sensing unit transmits a signal and the second sensing unit receives a signal. When a finger touches the antenna 111 of the second sensing unit, the signal transmitted by the antenna 111 of the first sensing unit is introduced into the human body, and the signal received by the second sensing unit becomes weaker. Based on the different transmission and reception coordination of the antenna 111 of the first sensing unit and the second sensing unit, the touch position of the finger can be confirmed according to the energy size of the signal received by the antenna 111 at different positions of the second sensing unit.

[0054] It is understandable that high impedance can be achieved by opening the circuit.

[0055] It can also be understood that the number of antennas and the number of signal channels of the first sensing unit and the second sensing unit may be the same or different, and those skilled in the art may set them according to actual needs.

[0056] It should be noted that the antenna 111 can be configured as a visible antenna arranged on a transparent or opaque substrate, or as a transparent antenna arranged on a transparent substrate. Specifically, the transparent substrate can be glass, FR4 or PVC, etc. The transparent antenna can 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 which is invisible to the naked eye, and the shape of the mesh of the mesh antenna can be square, circular, elliptical, diamond, semicircular, polygonal, irregular, etc., without limitation. Please refer to Figure 3 , showing a schematic diagram of a transparent antenna, the transparent antenna is rectangular in shape and has a square grid. Fig. 8A , 8B 8C is a schematic diagram showing another transparent antenna, Fig. 8A shows the antenna arrangement of the first sensing unit, Figure 8B shows the antenna arrangement of the second sensing unit, Figure 8C The antenna arrangement of the sensing unit 11 is shown. The transparent antenna includes a plurality of diamond-shaped units connected in series. Two adjacent diamond-shaped units are connected at vertices. The grid of each diamond-shaped unit is a diamond.

[0057] See also Fig. 9 , is a flow chart of a handwriting input method provided in an embodiment of the present invention. The handwriting input method provided in an embodiment of the present invention can be applied to the handwriting input device 10, and the handwriting input method includes:

[0058] 101. Provide the sensing unit 11;

[0059] 102. Provide the first control unit 12, wherein the first control unit 12 controls the first end 1111 of the first antenna to serve as a transmitting end, controls the first end 1111 of the second antenna to be connected to a common reference end, and transmits the first synchronization signal;

[0060] 103. Provide the second control unit 13 that is communicatively connected to the first control unit 12, wherein the second control unit 13 controls the second end 1112 of the first antenna to be connected to a common reference end according to the first synchronization signal, and controls the second end 1112 of the second antenna to be used as a transmitting end.

[0061] In this embodiment, the handwriting input method further includes:

[0062] The differential amplifier 15 is provided, the first control unit 12 controls the first end 1111 of the third antenna to be connected to the first input end of the differential amplifier 15, controls the first end 1111 of the fourth antenna to be connected to the second input end of the differential amplifier 15, and sends the second synchronization signal;

[0063] The second control unit 13 controls the second end 1112 of the third antenna to be connected to the common reference end according to the second synchronization signal, and controls the second end 1112 of the fourth antenna to be connected to the common reference end.

[0064] In some embodiments, the handwriting input method further includes:

[0065] A differential amplifier is provided, wherein the first control unit controls the first end of the third antenna to be connected to the first input end of the differential amplifier, controls the first end of the fourth antenna to be connected to the common reference end, and sends a second synchronization signal;

[0066] The second control unit controls the second end of the third antenna to be connected to the common reference end according to the second synchronization signal, and controls the second end of the fourth antenna to be connected to the second input end of the differential amplifier.

[0067] In some embodiments, the sensing unit includes a first sensing unit and a second sensing unit, and the handwriting input method further includes:

[0068] A differential amplifier is provided, the first control unit controls the first end of the antenna of the first sensing unit as a transmitting end, controls the first end of the antenna of the second sensing unit to be connected to the first input end of the differential amplifier, the second input end of the differential amplifier is connected to the common reference end, and sends a third synchronization signal,

[0069] The second control unit controls the second end of the antenna of the first sensing unit to be set to high impedance according to the third synchronization signal, and controls the second end of the antenna of the second sensing unit to be set to high impedance.

[0070] Compared with the prior art, the handwriting input device 10 provided by the present invention is provided with the first control unit 12 and the second control unit 13 which are communicatively connected, and the first end 1111 and the second end 1112 of the antenna 111 are respectively controlled by the first matrix switch 121 and the second matrix switch 131, so that the antenna 111 can adopt a strip antenna, and a loop antenna can be formed by selecting two antennas 111. The wiring of a single strip antenna is simple, the manufacturing is simple, and the cost is low; the first control unit 12 and the second control unit 13 which are communicatively connected can synchronously control the two antennas to transmit signals simultaneously, the first end 1111 of the first antenna is used as the transmitting end, and the second end 1112 of the second antenna is used as the transmitting end. The magnetic fields of the first antenna and the second antenna are superimposed, and a stronger transmitting signal can be obtained, which overcomes the defect that the first matrix switch 121 and the second matrix switch 131 have large on-resistances resulting in weak transmitting signals.

[0071] By using the two antennas 111 constituting a loop antenna and connecting the two input terminals of the differential amplifier 15 respectively, a stronger received signal can be obtained, thereby overcoming the defect that the first matrix switch 121 and the second matrix switch 131 have large on-resistances resulting in weak received signals.

[0072] 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, characterized in that: include: The sensing unit includes a plurality of antennas arranged in a queue, each of the antennas including a first end and a second end opposite to each other; The control unit includes a first control unit and a second control unit which are communicatively connected, wherein the first control unit includes a first matrix switch which is electrically connected to the first end, and the second control unit includes a second matrix switch which is electrically connected to the second end.

2. The handwriting input device according to claim 1, characterized in that: The antenna is a strip antenna and a transparent antenna.

3. The handwriting input device according to claim 1, characterized in that: The sensing unit has a transmitting state, and the first control unit is used to control the first end of the first antenna as a transmitting end through the first matrix switch, control the first end of the second antenna to be connected to a common reference end, and send a first synchronization signal; the second control unit is used to control the second end of the first antenna to be connected to the common reference end through the second matrix switch according to the first synchronization signal, and control the second end of the second antenna to be a transmitting end, wherein the first antenna and the second antenna are any two different antennas among the multiple antennas.

4. The handwriting input device according to claim 3, characterized in that: The first antenna and the second antenna are separated by at least two antennas.

5. The handwriting input device according to claim 1, characterized in that: The handwriting input device also includes a differential amplifier, the number of antennas is a, the first matrix switch includes at least a*b first analog switches, each antenna is electrically connected to the first matrix switch to form b first signal channels, at least one of the first signal channels is connected to the first input terminal of the differential amplifier, and at least one of the first signal channels is connected to the second input terminal of the differential amplifier, wherein a≥2, b≥2, and a and b are integers.

6. The handwriting input device according to claim 5, characterized in that: The sensing unit has a receiving state, and the first control unit is used to control the first end of the third antenna to be connected to the first input end of the differential amplifier, control the first end of the fourth antenna to be connected to the second input end of the differential amplifier, and send a second synchronization signal through the first matrix switch; the second control unit is used to control the second end of the third antenna to be connected to a common reference end through the second matrix switch according to the second synchronization signal, and control the second end of the fourth antenna to be connected to the common reference end, wherein the third antenna and the fourth antenna are any two different antennas among the multiple antennas.

7. The handwriting input device according to claim 5, characterized in that: The sensing unit has a receiving state, and the first control unit is used to control the first end of the third antenna to be connected to the first input end of the differential amplifier through the first matrix switch, control the first end of the fourth antenna to be connected to the common reference end, and send a second synchronization signal; the second control unit is used to control the second end of the third antenna to be connected to the common reference end through the second matrix switch according to the second synchronization signal, and control the second end of the fourth antenna to be connected to the second input end of the differential amplifier, wherein the third antenna and the fourth antenna are any two different antennas among the multiple antennas.

8. The handwriting input device according to claim 5, characterized in that: The sensing unit includes a first sensing unit and a second sensing unit, the antenna of the first sensing unit and the antenna of the second sensing unit are arranged crosswise, the handwriting input device has a capacitive mode, the first control unit is used to control the first end of the antenna of the first sensing unit as a transmitting end through the first matrix switch, control the first end of the antenna of the second sensing unit to be connected to the first input end of the differential amplifier, the second input end of the differential amplifier is connected to a common reference end, and send a third synchronization signal, the second control unit is used to control the second end of the antenna of the first sensing unit to be set to high impedance through the second matrix switch according to the third synchronization signal, and control the second end of the antenna of the second sensing unit to be set to high impedance.

9. A handwriting input method, characterized in that: include: Providing a sensing unit, the sensing unit comprising a plurality of antennas arranged in a queue, each of the antennas comprising a first end and a second end opposite to each other; Providing a first control unit, the first control unit controls the first end of the first antenna to serve as a transmitting end, controls the first end of the second antenna to be connected to a common reference end, and transmits a first synchronization signal, wherein the first antenna and the second antenna are any two different antennas among the plurality of antennas; A second control unit is provided that is communicatively connected to the first control unit. The second control unit controls the second end of the first antenna to be connected to a common reference end according to the first synchronization signal, and controls the second end of the second antenna to be used as a transmitting end.

10. The handwriting input method according to claim 9, characterized in that: Also includes: A differential amplifier is provided, wherein the first control unit controls the first end of the third antenna to be connected to the first input end of the differential amplifier, controls the first end of the fourth antenna to be connected to the second input end of the differential amplifier, and sends a second synchronization signal, wherein the third antenna and the fourth antenna are any two different antennas among the plurality of antennas; The second control unit controls the second end of the third antenna to be connected to a common reference end and controls the second end of the fourth antenna to be connected to a common reference end according to the second synchronization signal.

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