CN102929411A - Electromagnetic touch device - Google Patents
Electromagnetic touch device Download PDFInfo
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- CN102929411A CN102929411A CN2012103903608A CN201210390360A CN102929411A CN 102929411 A CN102929411 A CN 102929411A CN 2012103903608 A CN2012103903608 A CN 2012103903608A CN 201210390360 A CN201210390360 A CN 201210390360A CN 102929411 A CN102929411 A CN 102929411A
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Abstract
The invention relates to an electromagnetic touch device. The electromagnetic touch device comprises an antenna module and a control system, wherein the antenna module comprises a signal transmitting circuit and signal receiving antennae; the control system is connected with the antenna module and comprises signal amplifying circuits, a filter circuit, a detection and integral circuit, a Schmidt trigger circuit and a data processing and communication module, wherein the filter circuit is connected with the signal amplifying circuits, performs filtering processing on an amplified signal and outputs two signals; two signal receiving antennae are provided, and each signal receiving antenna is provided with a signal amplifying circuit; and the filter circuit is an addition and subtraction comparison filter circuit which simultaneously performs the filtering processing on the touch signals which are received by the two signal receiving antennae and are amplified. The electromagnetic touch device can be matched with a passive electromagnetic stylus and can also be matched with an active electromagnetic stylus by arranging the signal transmitting circuit and the two signal receiving antennae on the electromagnetic touch device at the same time and matching the addition and subtraction comparison filter circuit.
Description
Technical field
The present invention relates to the touch control technical field, relate in particular to a kind of electromagnetic touch-control device.
Background technology
The touch control technology more and more is applied in the electronic product field.At present, the touch screen technology of main flow mainly contains following several: resistance-type, condenser type and inductance type.Wherein, the inductive touch control screen can be divided into active and passive by principle of work, and active passive mainly is for the electromagnetism pointer.
The active electromagnetic contactor control device can be referred to as active electromagnetism contactor control device, its principle of work is: the electromagnetism pointer is transmission of electromagnetic signals initiatively, antenna plate receives signal and passes to control system, and then control system carries out signal to send touch information after the MCU processing of amplification filtering by control system.
Passive electrical magnetic-type contactor control device claims again the passive electromagnetic contactor control device, its principle of work is: the master control borad control signal is launched by antenna plate, the passive electromagnetic pointer can produce the oscillator signal of certain frequency after sensing signal, this signal is received by antenna plate and sends control system to, and then control system carries out signal to send touch information after the MCU processing of amplification filtering by control system.
Find that in actual use active electromagnetism contactor control device is quick on the draw in large size electro thoughts and feelings control application facet, pen is pressed more easily and is realized, is required to be the worry that active electromagnetism pointer is changed battery or charging in the use procedure but exist.And the passive electromagnetic pointer easily is disturbed because of the signal to noise ratio (S/N ratio) factor on master control borad.Existing electromagnetism contactor control device adopts low pass, the Hi-pass filter of traditional RC the electric circuit constitute, the principle of this traditional RC circuit filtering is that signal is decayed, low-pass filtering is more in the high band decay, high-pass filtering then is more in the low-frequency range decay, and the useful signal part that also can and then decay, particularly or undesired signal frequency range large in interference ratio and electromagnetism pointer transmit and are difficult to the better signal to noise ratio (S/N ratio) of acquisition by the high pass low-pass filtering under the close rugged surroundings of frequency range in the process of decay.
Summary of the invention
Technical matters to be solved by this invention is, a kind of electromagnetic touch-control device is provided, and can effectively cooperate respectively active electromagnetism pointer and passive electromagnetic pointer to use.
For solving the problems of the technologies described above, the invention provides following technical scheme: a kind of electromagnetic touch-control device comprises:
Antenna modules, described antenna modules comprise for to the signal transmission circuit of matching used electromagnetism pointer emissioning controling signal be used for receiving the signal receiving antenna of the touching signals of electromagnetism pointer emission; And
The control system that links to each other with antenna modules, described control system comprises:
Be connected in signal receiving antenna, the touching signals that receives amplified the signal amplification circuit of processing;
Be connected in signal amplification circuit so that filtering is processed and the filtering circuit of output two paths of signals to carrying out through amplifying signal;
Detection and integrating circuit, the first via signal that filtering circuit is exported carries out detection and Integral Processing;
Schmidt trigger circuit, the second road signal that filtering circuit is exported carries out the frequency phase-angle detection;
Data are processed and communication module, the first via signal of processing through detection and integrating circuit is carried out the analog to digital conversion comparison calculating the X/Y two-dimensional coordinate of electromagnetism pointer, and the second road signal of processing through schmidt trigger circuit is carried out frequency analyses calculation to determine electromagnetism pointer status;
Wherein, described signal receiving antenna is two-way, is equipped with one road signal amplification circuit for each road signal receiving antenna; Described filtering circuit is for touching signals that simultaneously described two paths of signals receiving antenna is received and through amplify processing and carry out relatively filtering circuit of plus-minus method that filtering processes.
Further, described signal transmission circuit comprises emitting antenna and signal countdown circuit.
Further, described signal receiving antenna is comprised of the closing coil of directions X and Y-direction.
Further, described electromagnetic touch-control device also comprises active electromagnetism pointer or passive electromagnetic pointer.
Further, antenna modules is connected to control system by flexible PCB.
Further, described data are processed and communication module also includes for the USB interface or the inter-integrated circuit that carry out communication with corresponding system end.
After adopting technique scheme, the present invention has following beneficial effect at least: the present invention is provided with signal transmission circuit and two paths of signals receiving antenna simultaneously on same electromagnetism contactor control device, and adopt relatively filtering circuit of plus-minus method, thereby make electromagnetic touch-control device of the present invention can cooperate the passive electromagnetic pointer to use, also can cooperate active electromagnetism pointer to use, range of application is wider.
The present invention is simultaneously two unidirectional coils of gating such as Xn and Xn+m reception signal once, if Xn receives the signal of electromagnetism pointer, Xn+m is exactly the undesired signal beyond the electromagnetism pointer signal so.And cooperate again plus-minus method comparison filtering circuit to carry out filtering, and to compare with low pass, Hi-pass filter that traditional RC forms, plus-minus method comparison filtering circuit can reach better filter effect, extracts the better signal of signal to noise ratio (S/N ratio).
Description of drawings
Fig. 1 is the system principle diagram of electromagnetic touch-control device of the present invention.
Embodiment
Need to prove that in the situation of not conflicting, embodiment and the feature among the embodiment among the application can mutually combine, and below in conjunction with the drawings and specific embodiments the present invention are described in further detail.
As shown in Figure 1, the invention provides a kind of electromagnetic touch-control device, comprising:
Antenna modules 1, described antenna modules 1 comprises for to the signal transmission circuit 10 of matching used electromagnetism pointer 3 emissioning controling signals be used for receiving the signal receiving antenna 12 of the touching signals of electromagnetism pointer 2 emissions, wherein, described signal transmission circuit 10 comprises emitting antenna 100 and signal countdown circuit 102, described signal receiving antenna 12 is provided with two-way, the same with the signal receiving antenna of existing electromagnetic touch-control device, signal receiving antenna 12 of the present invention also is comprised of the closing coil of directions X and Y-direction;
The control system 2 that links to each other with antenna modules 1 preferably, is to connect antenna modules 1 and control system 2 with flexible PCB, and described control system 2 comprises again:
Being connected in 12 pairs of touching signals that receive of signal receiving antenna and amplifying the signal amplification circuit 20 of processing, during implementation, is to be equipped with one road signal amplification circuit 20 for each road signal receiving antenna;
Be connected in signal amplification circuit 21 so that filtering is processed and the filtering circuit 21 of output two paths of signals to carrying out through amplifying signal, the filtering circuit 21 that the present invention adopts is for that receive to described two paths of signals receiving antenna 12 and carry out relatively filtering circuit of plus-minus method that filtering processes through amplifying the touching signals of processing simultaneously;
Detection and integrating circuit 22, the first via signal that filtering circuit 21 is exported carries out detection and Integral Processing;
Schmidt trigger circuit 24, the second road signal that filtering circuit 21 is exported carries out the frequency phase-angle detection;
Data are processed and communication module 26, first via signal through detection and integrating circuit 22 processing is carried out the analog to digital conversion comparison to calculate the X/Y two-dimensional coordinate of circuit electromagnetism pointer 3, and the second road signal of processing through schmidt trigger circuit 24 carried out frequency analyses calculation to determine electromagnetism pointer status, described data are processed and communication module 26 can adopt MCU.Described data are processed and communication module also includes for carrying out USB interface or the inter-integrated circuit of communication with corresponding system end, in order to treated touching signals is sent to system end.
In one embodiment, also can be described electromagnetic touch-control device and be equipped with electromagnetism pointer 3, described electromagnetism pointer 3 can be active electromagnetism pointer or passive electromagnetic pointer.
Below describe for the principle of work of electromagnetic touch-control device of the present invention.
At first, control system judges whether to exist active electromagnetism pointer, and namely whether active detecting has the touching signals that corresponding active electromagnetism pointer is sent, and processes if any then carrying out follow-up touch information; When not having the active touch control signal, then by the antenna modules emissioning controling signal, and then scan one by one the closing coil of X-direction and the Y-direction of receiving antenna, behind the touching signals that detects passive electromagnetic pointer feedback, then carry out follow-up touching signals and process, if do not detect yet the then emission of stop control signal of passive electromagnetic pointer, again detect the step of active electromagnetism pointer, so repeat to detect, until find have corresponding electromagnetism pointer to send touching signals.
When cooperating active electromagnetism pointer to use, because active time writer is comprised of power unit and oscillating circuit, oscillating circuit produces the sine wave of certain frequency and launches by inductance, signal receiving antenna 12 chooses respectively the coil of directions X and the coil of Y-direction to carry out the reception of touching signals by the control of MCU successively, and the touching signals that receives amplifies via signal amplification circuit.
Signal after the amplification carries out filtering by plus-minus method comparison filtering circuit again, the plus-minus method that the present invention adopts compares filtering circuit when work, to comprise signal and the simple direct addition of undesired signal of electromagnetism pointer touching signals and undesired signal stack or subtract each other, specifically addition is still subtracted each other and need to be determined according to the phase place of antenna modules 1 received signal, then subtract each other if phase place is identical, otherwise then addition, the i.e. touching signals of remaining electromagnetism pointer only after above-mentioned processing, thus realize filter function.During specific works, when scanning receives the directions X coil signal, open simultaneously two coil: Xn and Xn+m(m〉5), under equivalent environment, Xn is identical or close with the undesired signal that Xn+m receives, this undesired signal comprises the space Electromagnetic Interference, LCD interference backlight, interference that the antenna modules transmitting coil produces etc., with the signal of Xn and Xn+m respectively after amplifying, by adjusting gain so that when not having electromagnetism pointer signal to exist two paths of signals approaching as much as possible, and then carry out addition or subtract each other by plus-minus method comparison filtering circuit, concrete use adding circuit or subtraction circuit are the cabling mode decisions by antenna, specifically by the direction of current in the coil of antenna, if all direction of routing of coil are all identical, the direction that is signal end and earth terminal is consistent, the phase place of signal is identical so, then use subtraction circuit, otherwise use adding circuit.The undesired signal that the amplitude equal phase is identical is subtracted each other can be the undesired signal decrease.
Signal after amplification filtering is divided into two-way again, and input MCU carried out A/D conversion (mould/number conversion) relatively after the process detection of first via signal and integrating circuit carried out respective handling, thereby calculated the X/Y two-dimensional coordinate of electromagnetism pointer.The the second road signal enters MCU and carries out frequency analyses calculation behind schmidt trigger circuit, determine electromagnetism pointer status, sends touch information by MCU to corresponding system end again.
And when cooperating the passive electromagnetic pointer to use, because what form electric supply installation is the passive electromagnetic pointer do not take over, and the lc circuit that only has electric capacity and inductance to form.When not detecting the touching signals of active electromagnetism pointer, the square-wave signal of control signal radiation circuit emission preset frequency then, first successively take the coil of Y-direction as emitting antenna, the coil of directions X is receiving coil by channel selecting.The passive electromagnetic pointer receives square-wave signal, can produce the sine wave of certain frequency under the excitation of square-wave signal, and described sine wave passes through towards periphery spatial emission of an internal inductance again.The coil of the directions X of receiving antenna receives signal, by signal amplification circuit the touching signals of receiving is amplified again.
Signal after the amplification carries out filtering by plus-minus method comparison filtering circuit again, and the filtering processing mode when its filtering principle uses with the active electromagnetism pointer of mode and above-mentioned cooperation is identical.
Signal after amplification filtering is divided into two-way again, and input MCU carries out the A/D conversion relatively behind the process detection of first via signal and the integrating circuit, calculates the directions X coordinate of electromagnetism pointer, receives the Y-direction coordinate that calculates the electromagnetism pointer with the same manner again.The the second road signal then enters MCU and carries out frequency analyses calculation behind schmidt trigger circuit, determine electromagnetism pointer status.Finally send touch information to corresponding system end again by MCU again.
Although illustrated and described embodiments of the invention, for the ordinary skill in the art, be appreciated that without departing from the principles and spirit of the present invention and can carry out multiple variation, modification, replacement and modification to these embodiment, scope of the present invention is limited by claims and equivalency range thereof.
Claims (6)
1. electromagnetic touch-control device comprises:
Antenna modules, described antenna modules comprise for to the signal transmission circuit of matching used electromagnetism pointer emissioning controling signal be used for receiving the signal receiving antenna of the touching signals of electromagnetism pointer emission; And
The control system that links to each other with antenna modules, described control system comprises:
Be connected in signal receiving antenna, the touching signals that receives amplified the signal amplification circuit of processing;
Be connected in signal amplification circuit so that filtering is processed and the filtering circuit of output two paths of signals to carrying out through amplifying signal;
Detection and integrating circuit, the first via signal that filtering circuit is exported carries out detection and Integral Processing;
Schmidt trigger circuit, the second road signal that filtering circuit is exported carries out the frequency phase-angle detection;
Data are processed and communication module, the first via signal of processing through detection and integrating circuit is carried out the analog to digital conversion comparison calculating the X/Y two-dimensional coordinate of electromagnetism pointer, and the second road signal of processing through schmidt trigger circuit is carried out frequency analyses calculation to determine electromagnetism pointer status;
It is characterized in that described signal receiving antenna is two-way, be equipped with one road signal amplification circuit for each road signal receiving antenna; Described filtering circuit compares filtering circuit for the plus-minus method that simultaneously described two paths of signals receiving antenna is received and carry out the filtering processing through amplifying the touching signals of processing.
2. electromagnetic touch-control device as claimed in claim 1 is characterized in that, described signal transmission circuit comprises emitting antenna and signal countdown circuit.
3. electromagnetic touch-control device as claimed in claim 1 is characterized in that, described signal receiving antenna is comprised of the closing coil of directions X and Y-direction.
4. electromagnetic touch-control device as claimed in claim 1 is characterized in that, described electromagnetic touch-control device also comprises active electromagnetism pointer or passive electromagnetic pointer.
5. electromagnetic touch-control device as claimed in claim 1 is characterized in that antenna modules is connected to control system by flexible PCB.
6. electromagnetic touch-control device as claimed in claim 1 is characterized in that, described data are processed and communication module also includes for the USB interface or the inter-integrated circuit that carry out communication with corresponding system end.
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| CN201210390360.8A CN102929411B (en) | 2012-10-15 | 2012-10-15 | Electromagnetic touch device |
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| CN201210390360.8A CN102929411B (en) | 2012-10-15 | 2012-10-15 | Electromagnetic touch device |
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| CN105117037A (en) * | 2014-04-09 | 2015-12-02 | 马克西姆综合产品公司 | Hybrid pen device and method |
| CN105843444A (en) * | 2016-03-18 | 2016-08-10 | 广东小天才科技有限公司 | Signal coordinate processing method, circuit and electromagnetic writing equipment |
| CN109240518A (en) * | 2018-08-16 | 2019-01-18 | 汉王科技股份有限公司 | A kind of method for processing noise of electromagnetic handwriting equipment, device and storage medium |
| CN109508123A (en) * | 2019-01-16 | 2019-03-22 | 北京汉王鹏泰科技股份有限公司 | A kind of touch-control sensing unit, touch panel, touch control display apparatus and method |
| CN110413159A (en) * | 2019-07-25 | 2019-11-05 | 鲁伯特（北京）教育科技有限公司 | Electromagnetic touch handwriting device with automatic phase correction function |
| US10712871B2 (en) | 2017-03-20 | 2020-07-14 | Shenzhen GOODIX Technology Co., Ltd. | Method for processing signal from active pen, and active pen and touch screen thereof |
| CN112260661A (en) * | 2020-10-21 | 2021-01-22 | 深圳市绘王动漫科技有限公司 | Signal processing circuit and position detection device |
| CN113437514A (en) * | 2021-06-25 | 2021-09-24 | 歌尔科技有限公司 | Antenna device and portable electronic device |
| CN113686230A (en) * | 2021-09-06 | 2021-11-23 | 深圳市绘王动漫科技有限公司 | Method, device and system for solving quick scribing and breaking |
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| CN109240518B (en) * | 2018-08-16 | 2020-11-20 | 汉王科技股份有限公司 | Noise processing method and device of electromagnetic handwriting equipment and storage medium |
| CN109508123A (en) * | 2019-01-16 | 2019-03-22 | 北京汉王鹏泰科技股份有限公司 | A kind of touch-control sensing unit, touch panel, touch control display apparatus and method |
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| CN110413159B (en) * | 2019-07-25 | 2023-03-31 | 青岛罗博智慧教育技术有限公司 | Electromagnetic touch handwriting device with automatic phase correction function |
| CN112260661A (en) * | 2020-10-21 | 2021-01-22 | 深圳市绘王动漫科技有限公司 | Signal processing circuit and position detection device |
| CN113437514A (en) * | 2021-06-25 | 2021-09-24 | 歌尔科技有限公司 | Antenna device and portable electronic device |
| CN113686230A (en) * | 2021-09-06 | 2021-11-23 | 深圳市绘王动漫科技有限公司 | Method, device and system for solving quick scribing and breaking |
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