A projected capacitive calligraphy soft brush and digital presentation system

Abstract

The present invention discloses a projected capacitive calligraphy soft brush and a digital presentation system, wherein the projected capacitive calligraphy soft brush is disclosed, including a pen body and a pen head, the pen head is a flexible cone, including a weak electric field electrode layer, a reference electrode layer and a strong electric field electrode layer, and the pen head is divided into a pen head tip including a weak electric field electrode layer, a pen head middle including a weak electric field electrode layer and a reference electrode layer, and a pen head tail including a weak electric field electrode layer, a reference electrode layer and a strong electric field electrode layer along the axial direction of the pen head; an insulating layer is provided between the weak electric field electrode layer and the reference electrode layer, and between the reference electrode layer and the strong electric field electrode layer. The present invention also discloses a projected capacitive calligraphy soft brush, the pen head is a cone-shaped flexible silicone, the cone side surface of the flexible silicone is alternately spirally wound with a conductive, spaced first electrode and a second electrode, and the electrode area increases in sequence along the direction away from the pen head tip. The present invention also discloses a digital presentation system using the above-mentioned projected capacitive calligraphy soft brush.

Description

Technical Field

[0001] The invention relates to the field of capacitive pens, and in particular to a projected capacitive calligraphy soft pen and a digital presentation system. Background Art

[0002] In recent years, with the rapid development of electronic devices, capacitive touch technology has also developed rapidly, giving birth to the emerging application field of touch screen + stylus. After several years of development, active handwriting stylus has gradually been accepted and absorbed by mainstream mobile device manufacturers and operating system suppliers from a niche product, becoming a standard input device. USI (Universal Stylus Protocol) has become a standardized interface protocol for such products; compared with passive or passive capacitive pens, active stylus has more functional features, such as multi-level pressure sensitivity, pen tilt posture perception, etc., so it is widely welcomed by users in fields such as artistic creation.

[0003] An active capacitive stylus in the prior art, such as the active capacitive stylus disclosed in Chinese patent publication number CN213582120U, comprises a pen body and a pen tip, the pen body comprises a processing unit, and the pen tip comprises: a soft shell, comprising a first end and a second end opposite to each other, the cross section of the soft shell gradually increases from the first end to the second end, an elastic member hole is arranged inside the soft shell, and the second end of the soft shell is connected to the pen body; a conductive elastic member, comprising a third end and a fourth end opposite to each other, the conductive elastic member is arranged in the elastic member hole, the third end of the conductive elastic member extends out of the first end of the soft shell, and the fourth end of the conductive elastic member is connected to the processing unit; the processing unit is used to detect the pressure fed back by the conductive elastic member and generate pressure sensing data information; the conductive elastic member comprises a metal body and a conductive flexible part, the conductive flexible part is arranged at one end of the metal body to form the third end of the conductive elastic member, the conductive flexible part extends out of the first end of the soft shell, and the other end of the metal body is connected to the processing unit.

[0004] Another example is an active capacitive pen disclosed in a Chinese patent with publication number CN112306267A, which includes: a pen tip and a pen body; the pen tip includes a conductive soft shell and a filling fluid, a sealed cavity is provided in the conductive soft shell, a telescopic end is provided at one end of the sealed cavity, and the filling fluid is filled in the sealed cavity; the pen body is connected to the end of the pen tip where the telescopic end is provided, a sensing mechanism and a processing mechanism are provided in the pen body, and the processing mechanism is electrically connected to the sensing mechanism; the sensing end of the sensing mechanism is arranged corresponding to the telescopic end, so that the force of the telescopic end is transmitted to the sensing end of the sensing mechanism; the radial cross-sectional area of ​​the sealed cavity gradually increases from the end of the sealed cavity away from the telescopic end to the end of the sealed cavity close to the telescopic end.

[0005] Although the active capacitive pen disclosed in the above patent can meet the needs of hard-tip calligraphy, it is based on a normal electric field model and only detects position and pressure data, so it cannot meet the needs of creating and practicing Chinese soft-tip calligraphy. Summary of the invention

[0006] In order to solve the problems existing in the prior art, the present invention provides a projected capacitive calligraphy soft brush and a digital presentation system.

[0007] A projected capacitive calligraphy soft brush comprises a pen body and a pen tip fixed at the end of the pen body, wherein the pen tip is in the form of a flexible cone, and comprises a weak electric field electrode layer, a reference electrode layer and a strong electric field electrode layer arranged outward in sequence along a central axis, and the pen tip is divided into a pen tip tip portion, a pen tip middle portion and a pen tip tail portion along an axial direction of the pen tip, wherein the pen tip tip only comprises a weak electric field electrode layer, the pen tip middle portion comprises a weak electric field electrode layer and a reference electrode layer, and the pen tip tail portion comprises a weak electric field electrode layer, a reference electrode layer and a strong electric field electrode layer; the weak electric field electrode, the reference electrode and the strong electric field electrode are provided with an insulating layer;

[0008] When interacting with the capacitive touch screen, the contact surface of the pen tip is equivalent to the first capacitor, and the contact surface of the pen tail is equivalent to the second capacitor. The first capacitor is smaller than the second capacitor. By applying voltages V1, V0, and V2 to the conductive weak electric field electrode layer, the reference electrode layer, and the strong electric field electrode layer, it is equivalent to applying voltage V1 to the first capacitor and applying voltage V2 to the second capacitor, so that the projected electric field generated by the pen tip is smaller than the projected electric field generated by the pen tail, and a bias voltage is generated when interacting with the capacitive touch screen, wherein V0 <V1<V2。

[0009] Preferably, the weak electric field electrode layer is formed by a first bunching ring near the end of the pen tip that bunches a number of conductive metal wires arranged along the axial direction; the reference electrode layer is formed by a second bunching ring near the end of the pen tip that bunches a number of conductive metal wires arranged along the axial direction; the strong electric field electrode layer is formed by a third bunching ring near the end of the pen tip that bunches a number of conductive metal wires arranged along the axial direction;

[0010] The pen tip also includes a molding agent, which is filled in the internal gap and the outer surface of the pen tip to maintain the shape and elasticity of the pen tip;

[0011] The pen tip also includes a decorative layer, which is coated on the outer surface of the pen tip and is used to control the friction between the pen tip and the writing surface.

[0012] Preferably, the projected capacitive calligraphy soft brush further comprises an energy supply module, and the energy supply module comprises a power supply, a power management unit, and an electrode driving circuit;

[0013] The power supply is used to provide electrical energy;

[0014] The power management unit is used to manage the power supply to indicate the power supply status and control the power supply on or off;

[0015] The electrode driving circuit is used to convert the electric energy output by the power supply into different voltages, and according to the USI / MPP / HPP specification configuration, alternately apply voltages V0 and V2 to the reference electrode layer and the strong electric field electrode layer, and apply voltage V1 to the weak electric field electrode layer.

[0016] A projected capacitive calligraphy soft brush comprises a pen body and a pen tip fixed at the end of the pen body, wherein the pen tip is a conical flexible silicone, and a first conductive electrode and a second conductive electrode are alternately spirally wound on the conical side of the flexible silicone, wherein the first electrode and the second electrode are arranged at intervals, and the electrode areas increase in sequence along a direction away from the tip of the pen tip;

[0017] When interacting with the capacitive touch screen, the contact surface of the adjacent first electrode and the second electrode is equivalent to a single capacitor, so that multiple capacitors are formed along the direction away from the tip of the pen, and the capacitance increases successively with the increase of the electrode area. By applying different voltages to the first electrode and the second electrode respectively, it is equivalent to applying unequal voltages V3 and V4 to all capacitors, so that the projected electric field generated by the tip of the pen is smaller than the projected electric field generated by the tail of the pen, and a bias voltage is generated when interacting with the capacitive touch screen.

[0018] Preferably, a spirally encircled groove is provided on the conical side surface of the flexible silicone, and the first electrode and the second electrode are embedded in the groove.

[0019] Specifically, under this structure, the positions of the first electrode and the second electrode surrounding the conical side of the flexible silicone are more stable and will not easily undergo large displacements.

[0020] Preferably, the first electrode and the second electrode are electrode lines with gradually changing width when unfolded, including triangular electrode lines or rhombus electrode lines, and the rhombus size on the rhombus electrode lines gradually increases, so that when the electrode line is wrapped around the conical side of the flexible silicone, the formed electrode area increases successively in the direction away from the tip of the pen.

[0021] In addition, the first electrode and the second electrode may be, in addition to triangular electrode lines or diamond electrode lines, double helical lines with gradually varying widths, electrode lines in which a plurality of circles with gradually varying diameters are sequentially connected, and the like.

[0022] Preferably, the projected capacitive calligraphy soft brush further comprises an energy supply module, and the energy supply module comprises a power supply, a power management unit, and an electrode driving circuit;

[0023] The power supply is used to provide electrical energy;

[0024] The power management unit is used to manage the power supply to indicate the power supply status and control the power supply on or off;

[0025] The electrode driving circuit is used to convert the electric energy output by the power supply into different voltages, and according to the USI / MPP / HPP specification configuration, voltages V3 and V4 are alternately applied to the first electrode and the second electrode respectively, and V3 and V4 are not equal.

[0026] A digital presentation system, comprising a projected capacitive calligraphy soft pen as described in any one of the above items, a capacitive touch screen for writing with the projected capacitive calligraphy soft pen, a mutual capacitance voltage detection circuit, a data processing circuit, a calculation module, and a display screen for displaying the handwriting of the projected capacitive calligraphy soft pen;

[0027] The capacitive touch screen is provided with a plurality of detection electrode rows and a plurality of detection electrode columns which are vertically staggered with each other;

[0028] The mutual capacitance voltage detection circuit includes a row mutual capacitance voltage detection circuit and a column mutual capacitance voltage detection circuit, which are respectively used to detect the skewed mutual capacitance voltage data in the row direction and the column direction when the projected capacitance calligraphy soft pen writes on the capacitive touch screen from the detection electrode row and the detection electrode column;

[0029] The data processing circuit is used to identify the coordinates of the writing contact point according to the skew mutual capacitance voltage data, and calculate the writing contact point width and the writing contact point tail voltage vector;

[0030] The calculation module is used to render a sequence formed by the contact coordinates, the contact width and the contact tail voltage vector, and to form a writing handwriting based on the rendering result;

[0031] The display screen is used for visually presenting the handwriting.

[0032] Preferably, in the data processing circuit, the contact tail voltage vector is calculated according to the skew mutual capacitance voltage data, and the specific steps include:

[0033] According to the skew mutual capacitance voltage data Vx(i) read from several column electrodes corresponding to the same row direction, when i=m, the highest voltage value measured by Vx(i), the contact tail voltage vector Tx in the row direction is:

[0034]

[0035] Wherein, m is the contact position in the x direction, j = 1, 2, ..., k, Vx(m+j), Vx(mj) are the decreasing voltage values ​​measured by the column electrodes;

[0036] According to the skew mutual capacitance voltage data Vy(i) read from a number of row electrodes corresponding to the same column direction and the highest voltage value measured by Vy(i) when i=n, ​​the contact tail voltage vector Ty in the column direction is:

[0037]

[0038] Wherein, n is the contact position in the y direction, j = 1, 2, ..., k', Vy(n+j), Vy(nj) are the decreasing voltage values ​​measured by the row electrodes;

[0039] The calculated Tx and Ty are corrected, compensated and weighted and then output as the contact tail voltage vector detection result;

[0040] The contact width is: w = w x Vx(m)+w y Vy(n), where w x 、w y is the weight coefficient.

[0041] Specifically, due to the differences in consistency and sensitivity between the detection electrode rows and the detection electrode columns, Tx and Tx need to be corrected, compensated, and weighted according to actual conditions before output to reduce the error between writing and visualization.

[0042] Preferably, in the calculation module, a sequence formed by the contact coordinates (x=m, y=n), the contact width w and the contact tail voltage vector (Tx, Ty) is rendered; a handwriting vector is synthesized according to the value and direction of the contact tail voltage vector (Tx, Ty), and a dotted graphic outline with a pen tip is formed after combining the contact coordinates (x, y) and the contact width w, and the dotted outlines formed by the sequence of adjacent contacts are connected to form a writing handwriting.

[0043] Compared with the prior art, the benefits of the present invention include at least:

[0044] (1) The tip of the projected capacitive calligraphy brush includes a weak electric field electrode layer, a reference electrode layer, and a strong electric field electrode layer along the central axis from the inside to the outside, and voltages of different magnitudes are applied to the three electrode layers. Along the axis of the pen tip, the tip of the pen tip includes a weak electric field electrode layer, the middle part includes a weak electric field electrode layer and a reference electrode layer, and the tail part includes a weak electric field electrode layer, a reference electrode layer, and a strong electric field electrode layer. At the same time, an insulating layer is provided in combination with the weak electric field electrode, the reference electrode, and the strong electric field electrode, so that a bias voltage is formed when the pen tip of the projected capacitive calligraphy brush is energized. The projected capacitive calligraphy brush can simulate the shape of the brush tip when writing on a capacitive touch screen.

[0045] (2) The projected capacitive calligraphy pen includes a flexible silicone rubber and a first electrode and a second electrode that are insulated from each other and are alternately spirally wound on the flexible silicone rubber. By applying voltages of different magnitudes to the first electrode and the second electrode, a bias voltage is formed after the tip of the projected capacitive calligraphy pen is energized. The projected capacitive calligraphy pen can simulate the shape of the brush tip when writing on a capacitive touch screen.

[0046] (3) The two projected capacitive calligraphy pens provided by the present invention are applied to a digital presentation system. A capacitive touch screen provided with detection electrode rows, detection electrode columns, mutual capacitance voltage detection circuits, and data processing circuits are used to detect the coordinate data and width data of the projected capacitive calligraphy pens when writing on the capacitive touch screen, and the value of the voltage vector at the tail of the contact is calculated. A handwriting vector is synthesized according to the value and direction of the voltage vector at the tail of the contact. A dotted graphic outline with a pen tip is formed by combining the contact coordinates and the contact width. The dotted outlines formed by a sequence of adjacent contacts are connected to form a handwriting and visualized, so that the digital presentation system can meet the needs of Chinese soft-brush calligraphy or artistic creation and practice. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0048] Figure 1 A schematic diagram of the structure of a projected capacitive calligraphy brush provided by the present invention;

[0049] Figure 2 This is a schematic diagram of the pen head structure of the projected capacitive calligraphy soft pen provided by the present invention;

[0050] Figure 3 for Figure 2 The equivalent circuit of the pen tip;

[0051] Figure 4 A schematic diagram of another pen head structure of the projected capacitive calligraphy soft brush provided by the present invention;

[0052] Figure 5 for Figure 4 Equivalent circuit of the pen tip structure;

[0053] Figure 6 A schematic diagram of the triangular electrode lines of the projected capacitive calligraphy brush provided by the present invention;

[0054] Figure 7 A schematic diagram of the diamond-shaped electrode lines of the projected capacitive calligraphy soft pen provided by the present invention;

[0055] Figure 8 A schematic diagram of the structure of the digital presentation system provided by the present invention;

[0056] Fig. 9 A schematic diagram of the structure of a capacitive touch screen provided by the present invention;

[0057] Fig.10 A schematic diagram of handwriting rendering by the digital presentation system provided by the present invention. DETAILED DESCRIPTION

[0058] To make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific implementation methods described herein are only used to explain the present invention and do not limit the scope of protection of the present invention.

[0059] like Figure 1 As shown, the projected capacitive calligraphy soft pen provided in the embodiment includes a pen body 100 and a pen head 200 fixed at the end of the pen body 100 .

[0060] like Figure 2 As shown, the pen tip 200 is a flexible cone, including a weak electric field electrode layer 211, a reference electrode layer 212 and a strong electric field electrode layer 213 extending outward in sequence along the central axis, and the pen tip is divided into a pen tip, a pen tip middle and a pen tip tail along the axial direction of the pen tip, the pen tip tip only includes a weak electric field electrode layer 211, the pen tip middle includes a weak electric field electrode layer 211 and a reference electrode layer 212, and the pen tip tail includes a weak electric field electrode layer 211, a reference electrode layer 212 and a strong electric field electrode layer 213; the weak electric field electrode, the reference electrode and the strong electric field electrode are provided with an insulating layer, which can be understood as an insulating layer provided between the weak electric field electrode layer 211 and the reference electrode layer 212, and an insulating layer provided between the reference electrode layer 212 and the strong electric field electrode layer 213, and can also be understood as an insulating layer embodied on the weak electric field electrode, the reference electrode and the strong electric field electrode, that is, the electrodes are wrapped with enameled wire or similar metal wire.

[0061] like Figure 3 As shown, when interacting with the capacitive touch screen 400, the contact surface of the tip of the pen 200 is equivalent to the first capacitor C1, and the contact surface of the tail of the pen 200 is equivalent to the second capacitor C2, C1<C2, and by applying voltages V1, V0, and V2 to the conductive weak electric field electrode layer 211, the reference electrode layer 212, and the strong electric field electrode layer 213, respectively, it is equivalent to applying voltage V1 to C1 and applying voltage V2 to C2, so that the projected electric field generated by the tip of the pen 200 is smaller than the projected electric field generated by the tail of the pen 200, and a bias voltage is generated when interacting with the capacitive touch screen 400, wherein V0 <V1<V2。

[0062] The prerequisite for the projected capacitive calligraphy brush to meet the user's needs for Chinese soft brush calligraphy or artistic creation and practice is that the projected capacitive calligraphy brush can form a bias voltage when interacting with the capacitive touch screen 400. The structure of the pen tip 200 is that a weak electric field electrode layer 211 with a V1 voltage applied, a reference electrode layer 212 with a V0 voltage applied, and a strong electric field electrode layer 213 with a V2 voltage applied are arranged along the central axis from the inside to the outside, and the tip of the pen tip 200 includes the weak electric field electrode layer 211, the middle part includes the weak electric field electrode layer 211 and the reference electrode layer 212, and the tail includes the weak electric field electrode layer 211 and the reference electrode layer 212 as well as the strong electric field electrode layer 213. When the projected capacitive calligraphy brush and the capacitive touch screen 400 contact each other, the tip contacts first, then the middle part contacts, and finally the tail contacts. The structure of the projected capacitive calligraphy brush combined with its movement characteristics during writing can realize the formation of a bias voltage when it interacts with the capacitive touch screen 400.

[0063] The weak electric field electrode layer 211 is formed by bundling a number of conductive metal wires arranged along the axial direction through a first bundling ring 214 near the tail of the pen tip; the reference electrode layer 212 is formed by bundling a number of conductive metal wires arranged along the axial direction through a second bundling ring 215 near the tail of the pen tip; the strong electric field electrode layer 213 is formed by bundling a number of conductive metal wires arranged along the axial direction through a third bundling ring 216 near the tail of the pen tip.

[0064] The pen tip also includes a molding agent, which is filled in the internal gaps and the outer surface of the pen tip 200 to maintain the shape and elasticity of the pen tip 200.

[0065] The pen tip also includes a decorative layer, which is coated on the outer surface of the pen tip 200 and is used to control the friction between the pen tip 200 and the writing surface. The decorative layer can be a brush material or a surface spray material.

[0066] The reference electrode layer 212 surrounds the outside of the weak electric field electrode layer 211, and the strong electric field electrode layer 213 surrounds the outside of the reference electrode layer 212 to form a three-layer electrode layer structure of the pen tip 200, that is, the second bunching ring 215 and the third bunching ring 216 are both annular bunching rings. During use, the pen tip 200 will be constantly bent and squeezed, so it is necessary to fill and coat the internal gaps and outer surfaces of the pen tip 200 with a molding agent. In order to better control the projection calligraphy soft brush during writing, it is necessary to coat the outer surface of the pen tip 200 with a decorative layer for controlling the friction between the pen tip 200 and the writing surface.

[0067] like Figure 2 As shown, the projected capacitive calligraphy soft pen provided in the embodiment further includes an energy supply module, and the energy supply module includes a power supply 310, a power management unit 320, and an electrode driving circuit 330;

[0068] The power supply 310 is used to provide electrical energy;

[0069] The power management unit 320 is used to manage the power supply 310 to indicate the state of the power supply 310 and control the power supply 310 to be on or off;

[0070] The electrode driving circuit 330 is used to convert the electric energy output by the power supply 310 into different voltages, and apply voltages V0 and V2 alternately to the reference electrode layer 212 and the strong electric field electrode layer 213 according to the USI / MPP / HPP specification configuration, and apply voltage V1 to the weak electric field electrode layer 211.

[0071] The projected capacitive calligraphy brush needs to be driven by electric energy when in use, so a power supply 310 needs to be set. The power supply 310 usually selects a battery. When charging is required, the power management unit 320 will give an indication, and under this structure, a charging port 110 is provided on the pen body 100; the power supply 310 can also select a replaceable disposable battery. When the disposable battery needs to be replaced, the power management unit 320 will give an indication; the indication of charging or changing the battery can be displayed by the indicator light 120; in addition, the power management unit 320 also includes a switch 130 for controlling the power on or off of the pen head 200.

[0072] The embodiment also provides another projected capacitive calligraphy soft pen, comprising a pen body 100 and a pen head 200 fixed at the end of the pen body 100. Figure 4 As shown, the pen tip 200 is a conical flexible silicone 220, and the conical side of the flexible silicone 220 is alternately spirally wound with a conductive first electrode 221 and a second electrode 222, the first electrode 221 and the second electrode 222 are arranged at intervals, and the electrode area increases successively along the direction away from the tip of the pen tip 200.

[0073] like Figure 5 As shown, when interacting with the capacitive touch screen 400, the contact surface of the adjacent first electrode 221 and the second electrode 222 is equivalent to a single capacitor, so that multiple capacitors are formed along the direction away from the tip of the pen: C3, C4, C5..., and C3<C4<C5..., by applying different voltages to the first electrode 221 and the second electrode 222 respectively, it is equivalent to applying unequal voltages V3 and V4 to all capacitors, so that the projected electric field generated by the tip of the pen 200 is smaller than the projected electric field generated by the tail of the pen 200, and a bias voltage is generated when interacting with the capacitive touch screen 400.

[0074] Under this structure, a number of equivalent capacitors will be formed on the pen tip 200, and because the area of ​​the first electrode 221 and the second electrode 222 wrapped on the flexible silicone 220 increases successively in the direction away from the tip of the pen tip, the generated equivalent capacitance also increases successively in the direction away from the tip of the pen tip 200, that is, along the axial direction of the pen tip, the larger the contact area between the pen tip 200 and the capacitive touch screen 400, the larger the projected electric field generated, which can ensure that the projected capacitive calligraphy soft pen can always generate a bias voltage when writing on the capacitive touch screen 400.

[0075] In the embodiment, a spiral groove is provided on the conical side surface of the flexible silicone 220 , and the first electrode 221 and the second electrode 222 are embedded in the groove.

[0076] In this structure, the positions of the first electrode 221 and the second electrode 222 surrounding the conical side surface of the flexible silicone 220 are more stable and will not easily undergo large displacement.

[0077] like Figure 6 , 7 As shown, the first electrode 221 and the second electrode 222 are electrode lines with gradually changing widths when unfolded, including triangular electrode lines 223 or rhombus electrode lines 224, and the rhombus size on the rhombus electrode lines 224 gradually increases, so that when the electrode lines are wound around the conical side of the flexible silicone 220, the formed electrode area increases successively along the direction away from the tip of the pen head 200.

[0078] This structure can ensure that during the interaction between the projected capacitive calligraphy brush and the capacitive touch screen 400, the contact area from the tip to the tail increases and the electric field also gradually increases.

[0079] In addition, the first electrode 221 and the second electrode 222 may be, in addition to the triangular electrode line 223 or the diamond electrode line 224, a double helix line with a gradually changing width, an electrode line with a plurality of circles with gradually changing diameters connected in sequence, and the like.

[0080] like Figure 4 As shown, another projected capacitive calligraphy soft pen provided in the embodiment further includes an energy supply module, and the energy supply module includes a power supply 310, a power management unit 320, and an electrode driving circuit 330;

[0081] The power supply 310 is used to provide electrical energy;

[0082] The power management unit 320 is used to manage the power supply 310 to indicate the state of the power supply 310 and control the power supply 310 to be on or off;

[0083] The electrode driving circuit 330 is used to convert the electric energy output by the power supply 310 into different voltages, and to alternately apply voltages V3 and V4 to the first electrode 221 and the second electrode 222 according to the USI / MPP / HPP specification configuration, and V3 and V4 are not equal.

[0084] The projected capacitive calligraphy brush needs to be driven by electric energy when in use, so a power supply 310 needs to be set. The power supply 310 usually selects a battery. When charging is required, the power management unit 320 will give an indication, and under this structure, a charging port 110 is provided on the pen body 100; the power supply 310 can also select a replaceable disposable battery. When the disposable battery needs to be replaced, the power management unit 320 will give an indication; the indication of charging or changing the battery can be displayed by the indicator light 120; in addition, the power management unit 320 also includes a switch 130 for controlling the power on or off of the pen head 200.

[0085] like Figure 8 and Fig. 9 As shown, the embodiment further provides a digital presentation system, including a projected capacitive calligraphy soft pen as described in any of the above items, a capacitive touch screen 400 for writing with the projected capacitive calligraphy soft pen, a mutual capacitance voltage detection circuit, a data processing circuit 430, a calculation module, and a display screen 500 for displaying the handwriting of the projected capacitive calligraphy soft pen;

[0086] The capacitive touch screen 400 is provided with a plurality of detection electrode rows 410 and a plurality of detection electrode columns 420 that are vertically staggered with each other;

[0087] The mutual capacitance voltage detection circuit includes a row mutual capacitance voltage detection circuit 411 and a column mutual capacitance voltage detection circuit 421, which are respectively used to detect the skewed mutual capacitance voltage data in the row direction and the column direction when the projected capacitive calligraphy soft pen writes on the capacitive touch screen 400 from the detection electrode row 410 and the detection electrode column 420;

[0088] The data processing circuit 430 is used to identify the coordinates of the writing contact point according to the skew mutual capacitance voltage data, and calculate the writing contact point width and the writing contact point tail voltage vector;

[0089] The calculation module 600 is used to render a sequence formed by the contact coordinates, the contact width and the contact tail voltage vector, and to form a writing handwriting based on the rendering result;

[0090] The display screen 500 is used to visualize the handwriting, and the display screen can be a liquid crystal or electronic ink screen.

[0091] When the projected capacitive calligraphy brush writes on the capacitive touch screen 400, the detection electrode row 410 combined with the row mutual capacitance voltage detection circuit 411 detects the skewed mutual capacitance voltage in the row direction generated during writing, and the detection electrode column 420 combined with the column mutual capacitance voltage detection circuit 421 detects the skewed mutual capacitance voltage in the column direction generated during writing; the data processing circuit 430 processes the skewed mutual capacitance voltage data into contact coordinates, contact width, and contact tail voltage vector data and outputs them. After receiving the data, the display screen 500 renders the sequence formed by the data and then presents it visually.

[0092] like Fig. 9 As shown, in the data processing circuit 430, the contact tail voltage vector is calculated according to the skew mutual capacitance voltage data, and the specific steps include:

[0093] According to the skew mutual capacitance voltage data Vx(i) read from several column electrodes corresponding to the same row direction, when i=m, the highest voltage value measured by Vx(i) is:

[0094]

[0095] Wherein, m is the contact position in the x direction, j = 1, 2, ..., k, Vx(m+j), Vx(mj) are the decreasing voltage values ​​measured by the column electrodes;

[0096] According to the skew mutual capacitance voltage data Vy(i) read from a number of row electrodes corresponding to the same column direction and the highest voltage value measured by Vy(i) when i=n, ​​the contact tail voltage vector Ty in the column direction is:

[0097]

[0098] Wherein, n is the contact position in the y direction, j = 1, 2, ..., k', Vy(n+j), Vy(nj) are the decreasing voltage values ​​measured by the row electrodes;

[0099] The calculated Tx and Ty are corrected, compensated and weighted and then output as the contact tail voltage vector detection result.

[0100] Since there are differences in consistency and sensitivity between the detection electrode rows 410 and the detection electrode columns 420 , it is necessary to correct, compensate, and weight Tx and Ty according to actual conditions before outputting them to reduce the error between writing and visualization.

[0101] The contact width is: w = w x Vx(m)+w y Vy(n), where w x 、w y is the weight coefficient.

[0102] like Fig.10 As shown, in the calculation module 600, a sequence (x, y, w, Tx, Ty) formed by the contact coordinates (x=m, y=n), the contact width w and the contact tail voltage vector (Tx, Ty) is rendered, wherein Tx, Ty are data with + and - signs, and the symbols + and - represent the horizontal (x-axis) and column (y-axis) directions. A handwriting vector is synthesized according to the value and direction of the contact tail voltage vector (Tx, Ty), and a dotted graphic outline with a pen tip is formed by combining the contact coordinates (x, y) and the contact width w, and the dotted outlines formed by the sequence of adjacent contacts are connected to form a writing handwriting.

[0103] The calculation module 600 realizes the purpose of synthesizing the voltage vector of the tail of the contact into a handwriting vector and connecting the dotted contours formed by the sequence of adjacent contacts. In specific implementation, the calculation module connects and fills the contours of multiple contact points, and the formed trajectory continuously refreshes the display memory and outputs it to the display screen for display refresh according to the set time (generally 2-50ms per frame).

[0104] The computing module 600 includes circuits such as a CPU or MPU, a memory, an IO, and a communication interface. In addition, the digital presentation system also includes a CTP capacitive touch screen driving circuit and a TCON display screen driving circuit used in the rendering process. Both the CTP circuit and the TCON circuit are existing technologies, so they will not be described in detail here.

[0105] In the digital presentation system provided by the above-mentioned embodiment, the projected capacitive calligraphy soft pen can not only sense the change in the shape of the pen tip caused by pressure through the capacitive screen deflection electric field measurement, but also form a tail vector by controlling the pen tip, thereby producing the rendering effect of brush strokes, and can conveniently present, store, transmit and reproduce calligraphy and artistic works.

[0106] The specific implementation methods described above provide a detailed description of the technical solutions and beneficial effects of the present invention. It should be understood that the above is only the most preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, supplements and equivalent substitutions made within the scope of the principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A projected capacitive calligraphy soft pen, comprising a pen body and a pen head fixed at the end of the pen body, characterized in that: The pen tip is in the form of a flexible cone, comprising a weak electric field electrode layer, a reference electrode layer and a strong electric field electrode layer arranged outward in sequence along the central axis, and the pen tip is divided into a pen tip portion, a pen tip middle portion and a pen tip tail portion along the axial direction of the pen tip, the pen tip portion only comprising a weak electric field electrode layer, the pen tip middle portion comprising a weak electric field electrode layer and a reference electrode layer, and the pen tip tail portion comprising a weak electric field electrode layer, a reference electrode layer and a strong electric field electrode layer; the weak electric field electrode, the reference electrode and the strong electric field electrode are provided with an insulating layer; When interacting with the capacitive touch screen, the tip contacts first, then the middle contacts, and finally the tail contacts. The contact surface of the tip of the pen is equivalent to the first capacitor, and the contact surface of the tail of the pen is equivalent to the second capacitor. The first capacitor is smaller than the second capacitor. By applying voltages V1, V0, and V2 to the conductive weak electric field electrode layer, the reference electrode layer, and the strong electric field electrode layer, respectively, it is equivalent to applying voltage V1 to the first capacitor and applying voltage V2 to the second capacitor, so that the projected electric field generated by the tip of the pen is smaller than the projected electric field generated by the tail of the pen. The structure of the projected capacitive calligraphy soft pen is combined with its movement characteristics during writing, that is, it generates a biased voltage when interacting with the capacitive touch screen. Then, the projected capacitive calligraphy soft pen can simulate the shape of the pen tip handwriting of a brush when writing on the capacitive touch screen, so as to meet the needs of users for Chinese soft brush calligraphy or artistic creation and practice, wherein V0 <V1<V2。 2. The projected capacitive calligraphy brush according to claim 1, characterized in that: The weak electric field electrode layer is formed by a first bunching ring near the end of the pen tip that bunches a number of conductive metal wires arranged along the axial direction; the reference electrode layer is formed by a second bunching ring near the end of the pen tip that bunches a number of conductive metal wires arranged along the axial direction; the strong electric field electrode layer is formed by a third bunching ring near the end of the pen tip that bunches a number of conductive metal wires arranged along the axial direction; The pen tip also includes a molding agent, which is filled in the internal gap and the outer surface of the pen tip to maintain the shape and elasticity of the pen tip; The pen tip also includes a decorative layer, which is coated on the outer surface of the pen tip and is used to control the friction between the pen tip and the writing surface.

3. The projected capacitive calligraphy soft brush according to claim 1, characterized in that: It also includes an energy supply module, which includes a power supply, a power management unit, and an electrode driving circuit; The power supply is used to provide electrical energy; The power management unit is used to manage the power supply to indicate the power supply status and control the power supply on or off; The electrode driving circuit is used to convert the electric energy output by the power supply into different voltages, and according to the USI / MPP / HPP specification configuration, alternately apply voltages V0 and V2 to the reference electrode layer and the strong electric field electrode layer, and apply voltage V1 to the weak electric field electrode layer.

4. A projected capacitive calligraphy soft pen, comprising a pen body and a pen head fixed at the end of the pen body, characterized in that: The pen tip is a conical flexible silicone, and the conical side of the flexible silicone is alternately spirally wound with a conductive first electrode and a second electrode, the first electrode and the second electrode are arranged at intervals, and the electrode areas increase in sequence along the direction away from the tip of the pen tip; When interacting with the capacitive touch screen, the contact surface of the adjacent first electrode and the second electrode is equivalent to a single capacitor, so that multiple capacitors are formed along the direction away from the tip of the pen, and the capacitance increases successively with the increase of the electrode area, that is, along the axial direction of the pen tip, the larger the contact area between the pen tip and the capacitive touch screen, the larger the projected electric field generated. By applying different voltages to the first electrode and the second electrode respectively, it is equivalent to applying unequal voltages V3 and V4 to all capacitors, so that the projected electric field generated by the tip of the pen tip is smaller than the projected electric field generated by the tail of the pen tip, ensuring that the projected capacitive calligraphy soft pen generates a bias voltage when interacting with the capacitive touch screen. The projected capacitive calligraphy soft pen can simulate the shape of the pen tip handwriting of a brush when writing on the capacitive touch screen, so as to meet the needs of users for Chinese soft brush calligraphy or artistic creation and practice.

5. The projected capacitive calligraphy soft brush according to claim 4, characterized in that: A spiral groove is provided on the conical side of the flexible silicone, and the first electrode and the second electrode are embedded in the groove.

6. The projected capacitive calligraphy brush according to claim 4, characterized in that: When the first electrode and the second electrode are unfolded, they are electrode lines with gradually changing widths, including triangular electrode lines or rhombus electrode lines, and the rhombus size on the rhombus electrode lines gradually increases. In this way, when the electrode lines are wound around the conical side of the flexible silicone, the formed electrode area increases successively in the direction away from the tip of the pen.

7. The projected capacitive calligraphy soft brush according to claim 4, characterized in that: It also includes an energy supply module, which includes a power supply, a power management unit, and an electrode driving circuit; The power supply is used to provide electrical energy; The power management unit is used to manage the power supply to indicate the power supply status and control the power supply on or off; The electrode driving circuit is used to convert the electric energy output by the power supply into different voltages, and according to the USI / MPP / HPP specification configuration, voltages V3 and V4 are alternately applied to the first electrode and the second electrode respectively, and V3 and V4 are not equal.

8. A digital presentation system, characterized in that: It comprises a projected capacitive calligraphy brush as claimed in any one of claims 1 to 7, a capacitive touch screen for writing with the projected capacitive calligraphy brush, a mutual capacitance voltage detection circuit, a data processing circuit, a calculation module, and a display screen for displaying the handwriting of the projected capacitive calligraphy brush; The capacitive touch screen is provided with a plurality of detection electrode rows and a plurality of detection electrode columns which are vertically staggered with each other; The mutual capacitance voltage detection circuit includes a row mutual capacitance voltage detection circuit and a column mutual capacitance voltage detection circuit, which are respectively used to detect the skewed mutual capacitance voltage data in the row direction and the column direction when the projected capacitance calligraphy soft pen writes on the capacitive touch screen from the detection electrode row and the detection electrode column; The data processing circuit is used to identify the coordinates of the writing contact point according to the skew mutual capacitance voltage data, and calculate the writing contact point width and the writing contact point tail voltage vector; The calculation module is used to render a sequence formed by the contact coordinates, the contact width and the contact tail voltage vector, and to form a writing handwriting based on the rendering result; The display screen is used for visually presenting the handwriting.

9. The digital presentation system according to claim 8, characterized in that: In the data processing circuit, the contact tail voltage vector is calculated according to the skew mutual capacitance voltage data, and the specific steps include: According to the skew mutual capacitance voltage data Vx(i) read from several column electrodes corresponding to the same row direction, when i=m, the highest voltage value measured by Vx(i) is: Wherein, m is the contact position in the x direction, j = 1, 2, ..., k, Vx(m+j), Vx(mj) are the decreasing voltage values ​​measured by the column electrodes; According to the skew mutual capacitance voltage data Vy(i) read from a number of row electrodes corresponding to the same column direction, when i=n, ​​the highest voltage value measured by Vy(i), the contact tail voltage vector Ty in the column direction is: Wherein, n is the contact position in the y direction, j = 1, 2, ..., k', Vy(n+j), Vy(nj) are the decreasing voltage values ​​measured by the row electrodes; The calculated Tx and Ty are corrected, compensated and weighted and then output as the contact tail voltage vector detection result; The contact width is: w = w x Vx(m)+w y Vy(n), where w x 、w y is the weight coefficient.

10. The digital presentation system according to claim 9, characterized in that: In the calculation module, a sequence formed by the contact coordinates (x=m, y=n), the contact width w and the contact tail voltage vector (Tx, Ty) is rendered; a handwriting vector is synthesized according to the value and direction of the contact tail voltage vector (Tx, Ty), and a dotted graphic outline with a pen tip is formed by combining the contact coordinates (x, y) and the contact width w, and the dotted outlines formed by the sequence of adjacent contacts are connected to form a writing handwriting.

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