CN113823638A

CN113823638A - Rapid electromagnetic positioning system and method based on TFT substrate

Info

Publication number: CN113823638A
Application number: CN202111033252.0A
Authority: CN
Inventors: 李清波; 杨猛训
Original assignee: Shandong Lanbeisite Educational Equipment Group
Current assignee: Shandong Lanbeisite Educational Equipment Group
Priority date: 2021-09-03
Filing date: 2021-09-03
Publication date: 2021-12-21
Anticipated expiration: 2041-09-03
Also published as: CN113823638B

Abstract

The invention discloses a rapid electromagnetic positioning system and method based on a TFT substrate, comprising: a plurality of first wires arranged along a first direction and a plurality of second wires arranged along a second direction are integrated on the TFT substrate; The two ends are respectively led out through the FPC, and each lead wire on the FPC is controlled to be electrically connected according to the set rules, so as to form a plurality of first direction detection wires; The ground wires are connected to form a plurality of first direction coils; the two ends of the second wire are respectively led out through the FPC, and each lead wire on the FPC is controlled to be electrically connected according to the set rules to form a plurality of second direction detection wires; each A second direction detection wire is connected to the common ground wire arranged along the first direction to form a plurality of second direction coils. The invention reduces the number of detection lines of the electromagnetic induction signal and the corresponding circuit components, reduces the production cost, and improves the detection efficiency.

Description

Rapid electromagnetic positioning system and method based on TFT substrate

Technical Field

The invention relates to the technical field of electromagnetic positioning, in particular to a rapid electromagnetic positioning system and method based on a TFT substrate.

Background

The liquid crystal writing or display devices currently on the market mainly comprise:

(1) bistable liquid crystal writing/display devices (such as writing tablets or electronic papers) operate on the principle of writing, displaying and/or erasing by virtue of the bistable nature of the liquid crystal. For example, cholesteric liquid crystal is used as a writing board, the writing pressure track of a writing pen is recorded by changing the liquid crystal state at a pen point through the pressure acting on the liquid crystal writing board, and then corresponding writing contents are displayed; the cholesteric liquid crystal structure is changed by applying an electric field, so that the writing pressure track on the liquid crystal writing board disappears to realize erasing.

At present, a liquid crystal writing/display device based on a TFT substrate has been disclosed, which includes: a conductive layer, a bistable liquid crystal layer/polar liquid crystal material layer, and a substrate layer sequentially disposed; the TFT substrate is integrated on the base layer, a plurality of pixel units are arranged on the TFT substrate in an array mode, and a pixel electrode and a thin film field effect transistor (TFT) connected with the pixel electrode are arranged in each pixel unit; the TFT corresponding to each row of pixel units is connected by at least one first wire (hereinafter referred to as a row driving wire or a Gate wire) and supplies control voltage; the TFT corresponding to each row of pixel units is connected by at least one second lead (hereinafter referred to as a row driving line or a source line) and supplies input voltage; the voltage supplied to each first conducting wire (row driving wire or Gate wire) and each second conducting wire (column driving wire or source wire) on the TFT substrate is controlled to achieve a set voltage difference between the set pixel unit and the conducting layer, so that local erasing or display of a set area is realized.

(2) Common liquid crystal display screens (LCD, LED, OLED, etc.) are also based on TFT substrate structures, and display depends on internally disposed backlight or self-light emitting devices, and writing/displaying functions can be realized only in a power-on state, and writing/displaying cannot be realized when power is off.

The positioning method of the liquid crystal writing or display device mainly comprises the following steps: infrared positioning, optical or ultrasonic/distance sensor positioning, capacitive screen positioning or electromagnetic positioning.

When infrared positioning is utilized, one or more groups of infrared transmitting/receiving arrays are required to be added at the edge of the liquid crystal writing device; when the ultrasonic/distance sensor is used for positioning, at least two pairs of ultrasonic transceiving sensors are required to be added on the liquid crystal writing/displaying device; when the capacitive screen is used for positioning, the capacitive screen needs to be specially added.

When electromagnetic positioning is utilized, the electromagnetic positioning is carried out by adopting a copper wire arrangement mode in the prior art, and the mode is difficult to be used for a TFT substrate; in the prior art, the TFT substrate and the electromagnetic positioning net are combined to carry out electromagnetic positioning, and the mode easily causes adverse effect on the TFT substrate due to unevenness of the electromagnetic positioning net, thereby affecting the display effect; while also increasing the input cost and thickness of the liquid crystal writing/display device; the prior art adopts the mode of separately adding a TFT for electromagnetic positioning and a corresponding induction coil to carry out electromagnetic positioning on the basis of the structure of the existing TFT substrate, and the mode needs to change the structure of the TFT substrate, so that the realization difficulty is high. The original row driving wires and the original column driving wires of the TFT are utilized in the prior art, a plurality of electromagnetic induction coils are formed through electric connection so as to realize electromagnetic positioning, and because the number of the row driving wires and the column driving wires is large, a large number of positioning auxiliary circuit components are required to be added in the mode, so that the cost is high, and the detection efficiency is low.

Disclosure of Invention

Based on the above, the invention provides a rapid electromagnetic positioning system and method based on a TFT substrate, wires are newly added and led out on the TFT substrate, and a large number of wires are connected into a small number of detection wires through a set regular connecting wire, so that the cost is greatly reduced, and the detection efficiency is improved.

In order to achieve the above object, according to a first aspect of the present invention, there is provided a fast electromagnetic positioning system based on a TFT substrate, comprising: the TFT substrate is integrated with a plurality of first wires distributed along a first direction and a plurality of second wires distributed along a second direction;

the first conducting wires are electrically connected according to a set rule to form a plurality of first direction detection conducting wires; each first direction detection lead is respectively connected with a common ground wire arranged along a second direction to form a plurality of first direction coils for inducing electromagnetic signals;

the space between two adjacent first wires forming each first direction detection wire is arranged according to the mode of alternately connecting the first space and the second space; the first distance is odd multiple (for example, 3 times, 5 times or 7 times) of the distance between two adjacent first wires on the TFT substrate; the second distance is more than 2 times of the first distance;

the second leads are electrically connected according to a set rule to form a plurality of second direction detection leads; each second direction detection lead is connected with a common ground wire arranged along the first direction to form a plurality of second direction coils for inducing electromagnetic signals;

the space between two adjacent second wires forming each second direction detection wire is arranged according to the mode of alternately connecting the first space and the second space; the first distance is odd times (for example, 3 times, 5 times or 7 times) of the distance between two adjacent second wires on the TFT substrate; the second pitch is more than 2 times the first pitch.

According to a second aspect of the present invention, a method for fast electromagnetic positioning based on a TFT substrate is provided, the method is based on the above fast electromagnetic positioning system based on a TFT substrate; the method comprises the following steps:

receiving the electromagnetic induction signal of each first directional coil and performing signal frequency spectrum processing to obtain the intensity of the set frequency of the electromagnetic induction signal; sequencing the first direction coils according to the strength of the detection signals, and determining a second direction coordinate of the electromagnetic signal transmitting piece by looking up a table;

receiving the electromagnetic induction signal of each second direction coil and performing signal frequency spectrum processing to obtain the intensity of the set frequency of the electromagnetic induction signal; and sequencing the second direction coils according to the strength of the detection signals, and determining the first direction coordinate of the electromagnetic signal transmitting piece by looking up the table.

According to a third aspect of the present invention, there is provided a liquid crystal writing apparatus comprising: the conductive layer, the bistable liquid crystal layer and the substrate layer are arranged in sequence; the rapid electromagnetic positioning system based on the TFT substrate is integrated on the base layer.

According to a fourth aspect of the present invention, there is provided electronic paper comprising: the conductive layer, the polar material layer and the substrate layer are arranged in sequence; the rapid electromagnetic positioning system based on the TFT substrate is integrated on the base layer.

According to a fifth aspect of the present invention, there is provided a liquid crystal display comprising: the conductive layer, the liquid crystal layer and the substrate layer are arranged in sequence; the rapid electromagnetic positioning system based on the TFT substrate is integrated on the base layer.

Compared with the prior art, the invention has the beneficial effects that:

(1) the quick electromagnetic positioning system of the invention leads out two ends of each first lead and second lead through a flexible circuit board (hereinafter referred to as FPC) by re-arranging a plurality of mutually parallel first leads and second leads on a TFT substrate and connecting the leads according to a set rule, namely: connecting the set first conducting wires in series to form a first direction detection conducting wire, thus forming a plurality of first direction detection conducting wires; each first direction detection lead is electrically connected with a common ground wire arranged along a second direction to form a plurality of first direction coils; similarly, a plurality of second direction coils are formed; through the mode, a large number of wirings on the TFT substrate form a small number of first direction detection leads and second direction detection leads through connecting wires, the number of detection lines of electromagnetic induction signals and corresponding circuit components are reduced, the production cost is greatly reduced, the product thickness is reduced, the calculation amount of positioning is reduced, the response speed and the detection efficiency are improved, and the detectable area is increased.

(2) After the electromagnetic induction signals output by the electromagnetic positioning system are subjected to Discrete Fourier Transform (DFT), the set signal frequency and the strength of the signal frequency induced by each coil can be obtained; the calculation process is simple, and the positioning is accurate; meanwhile, according to the detected signal frequency, the frequency emitted by the electromagnetic emitting piece can be determined, and further the action state of the electromagnetic emitting piece and the liquid crystal writing/displaying device can be determined.

(3) The space between two adjacent first wires in the first direction detection wires is alternately connected according to a set first space and a set second space, and the space between two adjacent second wires in the second direction detection wires is alternately connected according to the set first space and the set second space; because the detection effect can be influenced by the change of the single first distance or the change of the single second distance, the optimal detection effect can be realized by the cooperation of the two distances, the algorithm can be simplified, the operation amount is reduced, and the detection speed and the detection precision are improved.

Additional features and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the invention and together with the description serve to explain the invention and not to limit the invention.

FIG. 1 is a schematic structural diagram of a fast electromagnetic positioning system based on a TFT substrate according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of a connection between a first direction detection wire and a common ground according to an embodiment of the present invention;

fig. 3 is a schematic diagram of an output signal processing circuit of the first directional coil and the second directional coil according to the embodiment of the invention.

Detailed Description

It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the disclosure. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.

Example one

According to an embodiment of the present invention, a fast electromagnetic positioning system based on a TFT substrate is disclosed, referring to fig. 1, including: the TFT substrate is integrated with a plurality of first wires which are arranged in parallel along a first direction and a plurality of second wires which are arranged in parallel along a second direction.

the space between two adjacent first wires forming each first direction detection wire is arranged according to the mode of alternately connecting the first space and the second space; the first distance is odd times (for example, 3 times, 5 times or 7 times) of the distance between every two adjacent first wires in all the first wires on the TFT substrate; the second distance is more than 2 times of the first distance;

the second conducting wires are electrically connected according to a set rule to form a plurality of second direction detection conducting wires; each second direction detection lead is connected with a common ground wire arranged along the first direction to form a plurality of second direction coils for inducing electromagnetic signals;

the space between two adjacent second wires forming each second direction detection wire is arranged according to the mode of alternately connecting the first space and the second space; the first distance is odd times (for example, 3 times, 5 times or 7 times) of the distance between every two adjacent second wires in all the second wires on the TFT substrate; the second pitch is more than 2 times the first pitch.

The first wires and the second wires are arranged at equal intervals, the arrangement interval can be larger than the original interval between each row driving wire or each column driving wire on the TFT substrate, the interval range selected by the embodiment is 3mm-13mm, and of course, technicians in the field can also freely select the interval range according to the requirements and the requirements of monitoring precision.

Referring to fig. 1, FPCs are respectively disposed at two ends of the TFT substrate along a first direction, and two ends of the first conductive line are respectively led out through a corresponding flexible circuit board FPC11 and a corresponding flexible circuit board FPC 12; the leading-out wires on the flexible circuit board FPC11 and the flexible circuit board FPC12 are controlled to be electrically connected according to a set rule to form a plurality of first direction detection lead wires; namely: according to the set rule, the set first leads are sequentially connected in series to form the first direction detection lead, so that a large number of first leads are changed into a small number of first direction detection leads, and the monitoring efficiency is improved.

With reference to fig. 2, each first-direction detecting conductive line is formed by connecting a plurality of first conductive lines in series, so that each first-direction detecting conductive line actually extends along the second direction, and an enclosing region is formed between the first-direction detecting conductive line and a common ground line disposed along the second direction; one end of each first direction detection lead is connected with a common ground wire arranged along the second direction, and the other end of each first direction detection lead outputs electromagnetic induction signals, so that a plurality of first direction coils used for inducing the electromagnetic signals are formed.

Similarly, two ends of the TFT substrate in the second direction are respectively provided with an FPC, two ends of the second wire are respectively led out through the flexible circuit board FPC21 and the flexible circuit board FPC22, and the flexible circuit board FPC21 and the flexible circuit board FPC22 are electrically connected by controlling respective lead-out wires on the flexible circuit board FPC22 according to a set rule, so as to form a plurality of second direction detection wires; one end of each second direction detection lead is connected with a common ground wire arranged along the first direction, and the other end of each second direction detection lead outputs electromagnetic induction signals, so that a plurality of second direction coils used for inducing the electromagnetic signals are formed.

In this embodiment, the distances between two adjacent first wires in the first direction detection wires are alternately connected according to a set first distance and a set second distance, and the distances between two adjacent second wires in the second direction detection wires are alternately connected according to the set first distance and the set second distance; because the detection effect can be influenced by the change of the single first distance or the change of the single second distance, the optimal detection effect can be realized by the cooperation of the two distances, the algorithm can be simplified, the operation amount is reduced, and the detection speed and the detection precision are improved.

In this embodiment, the first direction and the second direction may intersect perpendicularly to each other, or may intersect at a predetermined angle. The following description will be given taking the first direction as a vertical direction and the second direction as a horizontal direction as an example.

In this embodiment, a region between two adjacent first wires on the TFT substrate constitutes a minimum detection unit in the second direction; the region between two adjacent second conductive lines on the TFT substrate constitutes a minimum detection unit in the first direction.

Taking the first direction (vertical direction) as an example, the conditions that the leading-out wires on the FPC are controlled to be electrically connected according to the set rule are: any point in each minimum detection unit in the second direction of the TFT substrate is at least enclosed in an effective detection range of a first-direction coil formed by three first-direction detection leads; the first direction coils surrounding the different detection units are either completely different (i.e. all coils are different) or not completely identical (i.e. some coils are identical).

The effective detection range is that the point is located in a region surrounded by the first direction coil, that is, the point is located in a region surrounded by the first direction detection lead and the common ground wire arranged along the second direction.

Thus, for any point in each detection unit, at least three first direction coils can detect electromagnetic induction signals with set frequency, the first direction coils are sorted according to the strength of the induction signals, and the first direction coils obtained by the points in different detection units are not sorted identically, for example: the ranking of the strength of the sensing signals obtained by the point detection in the first detection unit may be: the first direction coil (r), the first direction coil (c) and the first direction coil (r), and the ordering of the strength of the induction signals detected by the points in the second detection unit may be: a first direction coil II, a first direction coil III and a first direction coil IV; the coordinate position of the point in the second direction, i.e. the abscissa, can be obtained by looking up the table.

Similarly, for the second direction (transverse direction), any point in each minimum detection unit in the first direction of the TFT substrate is at least enclosed in the effective detection range of a second direction coil formed by three second direction detection leads; the second direction coils surrounding the different detection units are completely different or not completely identical.

As a specific embodiment, assuming that 202 first conductive lines are arranged in the first direction, a specific connection manner can be referred to table 1.

TABLE 1 first wire connection mode

Table 1 shows the first direction detection wires one to twenty in connection, up indicating the connection to the next wire at the first end (top end) of the first wire and dn indicating the connection to the next wire at the second end (bottom end) of the first wire. 1,2, …, 202 indicate the arrangement order of the first conductors.

It should be noted that the meter may also be used as a connection mode of the first direction detection lead to the second direction detection lead; at this time, up indicates that the next wire is connected to the first end (left end) of the second wire, and dn indicates that the next wire is connected to the second end (right end) of the second wire. 1,2, …, 202 indicate the arrangement order of the second conductors.

Taking the first direction detection wire as an example, referring to fig. 1, the first wire 1 represents the 1 st first wire, the first wire 4 represents the 4 th first wire, the first wire 20 represents the 23 rd first wire, and the first wire 23 represents the 23 rd first wire; and so on. The first direction detection lead is formed by connecting 1 st, 4 th, 20 th, 23 th, 36 th, 39 th, 65 th, 87 th, 90 th, 113 th, 116 th, 136 th, 139 th, 159 th, 162 th, 175 th and 178 th first leads in series, wherein the 1 st first lead is connected with the 4 th first lead at the top end, the 4 th first lead is connected with the 20 th first lead at the bottom end, and the like to obtain a first direction detection lead; similarly, the second first-direction detection wire and the twenty first-direction detection wires are the same principle.

The twenty first direction detection wires can be obtained by connecting according to the wiring mode described in table 1, and each first direction detection wire is connected with a common ground wire arranged along the second direction to form twenty first direction coils for inducing electromagnetic signals. Meanwhile, the first direction coils surrounding different detection units are different or not completely the same at any point in the detection area at least in the effective detection range of the three first direction coils.

Similarly, the wiring scheme of table 1 above is also applicable to the second conductive line.

The output end of each first direction coil (namely the output of the first direction detection lead I, the second first direction detection lead … and the twenty first direction detection leads) is amplified and then connected to the main control unit, the main control unit is configured to receive the electromagnetic induction signals output by each first direction coil, the signals are subjected to Discrete Fourier Transform (DFT) after AD sampling to obtain the strength of the induction signals with set frequency, the first direction coils are sequenced according to the strength of the detection signals, and then the second direction coordinate of the electromagnetic signal transmitting part is determined by table lookup;

the output end of each second direction coil (namely the output of the first second direction detection lead, the second direction detection lead … and the twenty second direction detection lead) is amplified and then connected to the main control unit, and the main control unit is configured to receive the electromagnetic induction signals output by each second direction coil, perform Discrete Fourier Transform (DFT) after AD sampling, and obtain the intensity of the electromagnetic induction signals with set frequency; and sequencing the second direction coils according to the strength of the detection signals, and determining the first direction coordinate of the electromagnetic signal transmitting piece by looking up the table.

Specifically, with reference to fig. 3, the output end of each first directional coil may be connected to an analog switch, the output is gated by the analog switch, and the output of the analog switch is connected to the main control unit after being sequentially connected to the amplifying filter and the programmable amplifier. And similarly, the output end of each second direction coil is connected to the analog switch, the output is gated through the analog switch, and the output of the analog switch is connected with the amplifying filter and the programmable amplifier in sequence and then is connected to the main control unit.

And finally, obtaining the frequency and action position of the electromagnetic signal emitted by the electromagnetic signal emitting piece.

Example two

According to the embodiment of the invention, a rapid electromagnetic positioning method based on a TFT substrate is disclosed, and the method is based on the rapid electromagnetic positioning system based on the TFT substrate in the first embodiment; the method specifically comprises the following steps:

receiving the electromagnetic induction signal of each first directional coil and performing signal frequency spectrum processing to obtain the intensity of the electromagnetic induction signal with set frequency; sequencing the first direction coils according to the strength of the detection signals, and determining a second direction coordinate of the electromagnetic signal transmitting piece by looking up a table;

receiving the electromagnetic induction signal of each second direction coil and performing signal frequency spectrum processing to obtain the intensity of the electromagnetic induction signal with set frequency; and sequencing the second direction coils according to the strength of the detection signals, and determining the first direction coordinate of the electromagnetic signal transmitting piece by looking up the table.

EXAMPLE III

According to an embodiment of the present invention, there is disclosed an embodiment of a liquid crystal writing apparatus including: the conductive layer, the bistable liquid crystal layer and the substrate layer are arranged in sequence; the fast electromagnetic positioning system based on the TFT substrate in the first embodiment is integrated on the base layer.

As an alternative embodiment, the liquid crystal writing apparatus further comprises: an electromagnetic pen/eraser capable of emitting an electromagnetic signal; and determining the frequency of the electromagnetic signal emitted by the electromagnetic pen/erasing piece and the position acted on the liquid crystal writing device according to the frequency and the intensity of the detected electromagnetic induction signal.

Such as: when the electromagnetic pen is contacted with the writing panel, the frequency of the emitted electromagnetic signal is f1, and when the electromagnetic pen is lifted and is not contacted with the writing panel, the frequency of the emitted electromagnetic signal is f 2; when the electromagnetic pen stops working, no electromagnetic signal is sent out. The current working state of the electromagnetic pen can be judged according to the frequency of the detected induction signal; if the frequency of the detected electromagnetic induction signal is f1, the electromagnetic pen is in contact with the writing panel at the moment, and if the frequency of the detected electromagnetic induction signal is f2, the electromagnetic pen is lifted and is not in contact with the writing panel at the moment; if the electromagnetic induction signal is not detected, it indicates that the electromagnetic pen is not stopped or is far away from the writing panel.

Of course, as long as the frequency of the sensing signal is f1 or f2, the position of the electromagnetic pen is located. The same holds true for the electromagnetic eraser.

The embodiment can realize the display and storage of handwriting or the erasure of the handwriting based on the position of electromagnetic positioning.

The liquid crystal writing board of the embodiment can be an electronic product such as a liquid crystal blackboard, a liquid crystal writing board or a liquid crystal drawing board.

Example four

According to an embodiment of the present invention, there is disclosed an embodiment of an electronic paper, including: the conductive layer, the polar material layer and the substrate layer are arranged in sequence; the fast electromagnetic positioning system based on the TFT substrate in the first embodiment is integrated on the base layer.

As an optional implementation, the electronic paper further includes: an electromagnetic pen/eraser capable of emitting an electromagnetic signal; and determining the frequency of the electromagnetic signal emitted by the electromagnetic pen/erasing piece and the position acted on the liquid crystal writing device according to the frequency and the intensity of the detected electromagnetic induction signal.

The electronic paper of the embodiment may include electronic paper related products such as an electronic paper reader or an electronic paper tablet computer.

EXAMPLE five

According to an embodiment of the present invention, there is disclosed an embodiment of a liquid crystal display including: the conductive layer, the liquid crystal layer and the substrate layer are arranged in sequence; the fast electromagnetic positioning system based on the TFT substrate in the first embodiment is integrated on the base layer.

As an optional embodiment, the liquid crystal display further includes: an electromagnetic pen/eraser capable of emitting an electromagnetic signal; and determining the frequency of the electromagnetic signal emitted by the electromagnetic pen/erasing piece and the position acted on the liquid crystal writing device according to the frequency and the intensity of the detected electromagnetic induction signal.

The liquid crystal display in the embodiment can be an electronic product such as a mobile phone, a tablet, a notebook computer, a television screen and the like.

Although the embodiments of the present invention have been described with reference to the accompanying drawings, it is not intended to limit the scope of the present invention, and it should be understood by those skilled in the art that various modifications and variations can be made without inventive efforts by those skilled in the art based on the technical solution of the present invention.

Claims

1. A rapid electromagnetic positioning system based on a TFT substrate, characterized by comprising: a TFT substrate on which a plurality of first wires arranged along a first direction are integrated, and a plurality of first wires arranged along a second direction are integrated on the TFT substrate the second wire;

The first wires are electrically connected according to the set rules to form a plurality of first direction detection wires; A first direction coil for inducing electromagnetic signals;

The spacing between the two adjacent first wires constituting each first direction detection wire is arranged in a manner that the first spacing and the second spacing are alternately connected; the first spacing is the adjacent two first wires on the TFT substrate Odd multiples of the spacing; the second spacing is more than 2 times the first spacing;

The second wires are electrically connected according to the set rules to form a plurality of second direction detection wires; The second direction coil of the electromagnetic signal;

The spacing between two adjacent second wires constituting each second direction detection wire is arranged in a manner of alternately connecting the first spacing and the second spacing; the first spacing is the adjacent two second wires on the TFT substrate Odd multiples of the spacing; the second spacing is more than 2 times the first spacing.

2 . The fast electromagnetic positioning system based on a TFT substrate according to claim 1 , wherein the two ends of the first wire are electrically connected according to a set rule, and the plurality of first direction detection wires formed meet the following requirements: 3 . condition:

The area between two adjacent first wires on the TFT substrate is taken as the minimum detection unit in the second direction of the TFT substrate; any point in each of the minimum detection units is surrounded by at least three detection wires in the first direction. Within the effective detection range of the formed first direction coils; the first direction coils surrounding different detection units are completely different or not identical.

3. The fast electromagnetic positioning system based on a TFT substrate according to claim 1, wherein the two ends of the second wire are electrically connected according to a set rule, and the plurality of second direction detection wires formed meet the following requirements: condition:

The area between two adjacent second wires on the TFT substrate is taken as the minimum detection unit in the first direction of the TFT substrate; any point in each of the minimum detection units is surrounded by at least three detection wires in the second direction. Within the effective detection range of the formed second direction coils; the second direction coils surrounding different detection units are completely different or not identical.

4. A fast electromagnetic positioning system based on a TFT substrate according to claim 1, wherein the two ends of the first wire are drawn out through the flexible circuit board, and each lead wire is controlled to conduct electricity according to a set rule. connected to form a plurality of first direction detection wires.

5. A fast electromagnetic positioning system based on a TFT substrate according to claim 1, wherein both ends of the second wire are drawn out through the flexible circuit board, and each lead wire is controlled to be electrically connected according to a set rule, to form a plurality of second direction detection wires.

6 . The rapid electromagnetic positioning system based on a TFT substrate according to claim 1 , wherein the first wires are electrically connected according to a set rule to form a plurality of first direction detection wires, and the connection The rules are as follows:

Among them, up means that the first end of the current first wire is connected to the next first wire, dn means that the second end of the current first wire is connected to the next first wire; 1, 2, ..., 202 respectively Indicates the wire number and position of the first wire; 1, 2, . . . , 20 respectively indicate the formed first direction detection wire.

7 . The rapid electromagnetic positioning system based on a TFT substrate as claimed in claim 1 , wherein the first wires are parallel to each other and have the same spacing; the second wires are parallel to each other and have the same spacing. 8 .

8 . The fast electromagnetic positioning system based on a TFT substrate according to claim 1 , further comprising a main control unit, wherein the main control unit is configured to receive each of the first direction coils and each of the second direction coils. 9 . The output electromagnetic induction signal is subjected to spectrum processing to obtain the intensity of the set frequency of each induction signal, and then the position of the electromagnetic signal transmitter and the frequency of the electromagnetic signal are determined by looking up the table.

9 . The fast electromagnetic positioning system based on a TFT substrate according to claim 8 , wherein the output end of each first direction coil is connected to the main control unit after being connected to an operational amplifier. 10 .

10. A fast electromagnetic positioning method based on a TFT substrate, the method is based on the fast electromagnetic positioning system based on a TFT substrate according to any one of claims 1-9; characterized in that, the method comprises:

Receive the electromagnetic induction signal of each first direction coil and perform signal spectrum processing to obtain the strength of the set frequency of the electromagnetic induction signal; sort the first direction coils according to the strength of the detection signal, and then look up the table to determine the first direction of the electromagnetic signal transmitter. two-direction coordinates;

Receive the electromagnetic induction signal of each second-direction coil and perform signal spectrum processing to obtain the strength of the set frequency of the electromagnetic induction signal; sort the second-direction coils according to the strength of the detection signal, and then look up the table to determine the first electromagnetic signal transmitter. A direction coordinate.

11. A liquid crystal writing device, characterized in that it comprises: a conductive layer, a bistable liquid crystal layer and a base layer arranged in sequence; the base layer is integrated with the TFT-based substrate described in any one of claims 1-9 rapid electromagnetic positioning system.

12. A liquid crystal writing device as claimed in claim 1, further comprising: an electromagnetic pen/eraser capable of sending out electromagnetic signals; determining the electromagnetic pen/eraser according to the frequency and intensity of the detected electromagnetic induction signals The frequency of the electromagnetic signal emitted by the erasing element and its position on the liquid crystal writing device.

13. An electronic paper, characterized in that it comprises: a conductive layer, a polar material layer and a base layer which are arranged in sequence; Electromagnetic positioning system.

14. The electronic paper according to claim 13, further comprising: an electromagnetic pen/eraser capable of sending out electromagnetic signals; determining the electromagnetic pen/eraser according to the frequency and intensity of the detected electromagnetic induction signals The frequency of the electromagnetic signal emitted by the remover and its position on the liquid crystal writing device.

15. A liquid crystal display, comprising: a conductive layer, a liquid crystal layer and a base layer arranged in sequence; the base layer is integrated with the fast electromagnetic positioning based on a TFT substrate according to any one of claims 1-9 system.

16. A liquid crystal display as claimed in claim 15, further comprising: an electromagnetic pen/eraser capable of sending out electromagnetic signals; determining the electromagnetic pen/eraser according to the frequency and intensity of the detected electromagnetic induction signals The frequency of the electromagnetic signal emitted by the remover and its position on the liquid crystal writing device.