Circuit structure of infrared touch frame, infrared touch frame and infrared touch screen

Abstract

The utility model relates to a circuit structure of an infrared touch frame, the infrared touch frame and an infrared touch screen. The circuit structure of the infrared touch frame comprises a plurality of circuit board cards which are in cascade connection, wherein the circuit board card is sequentially provided with a front-end terminal, a board card circuit and a rear-end terminal; the circuit board cards are in cascade connection through transmission lines, and the previous circuit board card is connected with the front-end terminal of the next circuit board card through the rear-end terminal; the front end terminal of each circuit board card is connected with a first capacitor network, and the rear end terminal of each circuit board card is connected with a second capacitor network; the first capacitor network shapes and filters a signal waveform input to the circuit board card and then enters the board card circuit, and the second capacitor network shapes and filters an output signal waveform and then outputs the signal waveform to the next circuit board card. According to the technical scheme, the energy of electromagnetic interference radiation is reduced, and the consistency and stability of the infrared touch frame are guaranteed.

Description

Technical Field

[0001] The present application relates to the field of infrared touch control technology, and in particular to a circuit structure of an infrared touch frame, an infrared touch frame and an infrared touch screen. Background Art

[0002] Currently, the infrared touch frame of large-size screens on the market mainly transmits infrared light signals through transmitting lamps, and then the corresponding receiving lamps receive the corresponding infrared light signals, which are then processed by relevant signal circuit modules to achieve the touch function.

[0003] The infrared touch frame includes multiple circuit boards, and each circuit board is powered and transmitted data through transmission lines. Currently, large electronic products need to undergo certain electromagnetic interference (EMI) certifications. The power supply and data transmission methods of the infrared touch frame will cause certain energy radiation, so it will cause certain electromagnetic radiation interference to the circuit structure.

[0004] In order to reduce electromagnetic radiation interference, common infrared touch frames use the current limiting, matching and filtering characteristics of resistors and capacitors to filter signals or reduce part of the electromagnetic interference radiation energy. However, due to the mutual cascading characteristics of the circuit boards at all levels of the infrared touch frame, the transmission line between the head and tail circuit boards is relatively long, resulting in relatively large impedance and fluctuation characteristics, which makes the infrared touch frame still prone to relatively strong electromagnetic radiation interference energy, affecting the technical application prospects and market demand of the infrared touch frame. Utility Model Content

[0005] The purpose of the present application is to solve one of the above technical defects and provide a circuit structure of an infrared touch frame, an infrared touch frame and an infrared touch screen to reduce the interference of electromagnetic radiation on the circuit board of the infrared touch frame.

[0006] A circuit structure of an infrared touch frame, comprising: a plurality of circuit boards connected in cascade; wherein the circuit boards are provided with front-end terminals, board circuits and rear-end terminals in sequence;

[0007] Each circuit board card is cascade-connected through a transmission line, and the upper circuit board card is connected to the front-end terminal of the next circuit board card through the rear-end terminal;

[0008] A first capacitor network is connected to the front end terminal of each circuit board card, and a second capacitor network is connected to the rear end terminal of each circuit board card;

[0009] The first capacitor network shapes and filters the signal waveform input to the circuit board card before it enters the board card circuit, and the second capacitor network shapes and filters the output signal waveform before it is output to the next circuit board card.

[0010] An infrared touch frame, characterized by comprising: the circuit structure of the infrared touch frame.

[0011] An infrared touch screen comprises: a display screen and the infrared touch frame.

[0012] The technical solution of the present application makes full use of the characteristics of capacitor filtering and the voltage being unable to change suddenly, and sets a capacitor network at the front end of the circuit board card, so that the power supply and data transmission signals are relatively stable. On the other hand, in view of the cascade characteristics of each circuit board card of the infrared touch frame, the power lines of the head and tail circuit boards are relatively long, and a capacitor network is also set at the rear end of each circuit board card, so that the capacitor network of the circuit board card is distributed at the front and rear ends of the circuit board card, reducing the energy of electromagnetic interference radiation, improving the stability of power supply and data transmission at the rear end of the circuit board card, ensuring the consistency and stability of the infrared touch frame, and being better compatible with various types of upper system terminals, and also improving the compatibility and reliability of the infrared touch frame.

[0013] Additional aspects and advantages of the present application will be partially given in the following description, which will become apparent from the following description, or will be understood through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0015] Figure 1 This is a schematic diagram of the circuit structure of a conventional infrared touch frame;

[0016] Figure 2 is a schematic diagram of the structure of a circuit board card of an embodiment;

[0017] Figure 3 is a schematic diagram of the circuit structure of an infrared touch frame of an embodiment;

[0018] Figure 4 The infrared touch frame structure diagram of an embodiment is shown. DETAILED DESCRIPTION

[0019] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and cannot be interpreted as limiting the present application.

[0020] Those skilled in the art will appreciate that, unless otherwise stated, the singular forms "a", "an", "said" and "the" used herein may also include plural forms. It should be further understood that the term "comprising" used in the specification of the present application refers to the presence of the features, integers, steps, operations, but does not exclude the presence or addition of one or more other features, integers, steps, operations.

[0021] The technical solution of the present application is an improvement on the circuit structure of an infrared touch frame. Taking an infrared touch frame using a USB interface as an example, the infrared touch frame is powered by a USB power supply, and the data transmission method of the infrared touch frame uses a USB communication method to transmit data to an upper system end. The upper system end may include a PC, an Android board, a display, a power board, a screen driver board, and connecting cables, etc., that is, the rest of the equipment of the entire machine except the infrared touch frame.

[0022] like Figure 1 As shown, Figure 1 This is a schematic diagram of the circuit structure of a conventional infrared touch frame, power supply and data transmission mode. It consists of an upper system end, a mainboard card of the infrared touch frame, N transmitting boards and M receiving boards to form a complete set of system functions. Each circuit board is equipped with a board circuit; the front-end terminal of the mainboard card is connected to the upper system end, and the rear-end terminal of the mainboard card is respectively connected to the front-end terminal of the cascaded first-level transmitting board and the front-end terminal of the cascaded first-level receiving board; N transmitting boards are connected in sequence in cascade connection, and M receiving boards are connected in sequence in cascade connection. Figure 1 As shown, the power supply and data transmission of the infrared touch frame will have certain electromagnetic radiation, so it is necessary to further design the circuit for its power supply and data transmission to weaken its electromagnetic interference radiation ability. The circuit design of the power supply and data transmission of the infrared touch frame usually uses the current limiting, matching and filtering characteristics of the resistor and capacitor to filter the signal or reduce part of the electromagnetic interference radiation energy, and the capacitor of its power supply filter is basically concentrated at the front end of the board. However, this solution has certain problems. When the line design of the USB power supply and data transmission line on the upper system side is relatively poor, when it is synchronously given to the infrared touch frame, due to the mutual cascading characteristics of the circuit boards of each level of the infrared touch frame, the positive and negative lines of the power supply of the cascaded head and tail circuit boards are longer, and the longer the line, the greater the power supply impedance and fluctuation characteristics will be, which will have a relatively large negative impact on the infrared touch frame, causing the power supply system of the infrared touch frame to be unstable and the USB transmission data to be seriously interfered with.

[0023] In order to overcome the interference problem, the usual practice is to readjust the hardware parameters or devices to adapt to this special upper-layer system end to avoid excessive radiation energy of its electromagnetic interference. However, this also increases the design complexity and cost of the infrared touch frame, and also causes the consistency and stability of the infrared touch frame to be relatively poor, and it cannot be universally and effectively adapted to various types of upper-layer system ends.

[0024] To this end, the present application provides a circuit structure of an infrared touch frame, which includes: a plurality of circuit boards connected in cascade; Figure 2 As shown, Figure 2 The schematic diagram of the structure of the circuit board card of an embodiment is shown. Each circuit board card is provided with a front-end terminal, a card circuit and a rear-end terminal in sequence.

[0025] Each circuit board card is cascade-connected via a transmission line, where the previous circuit board card is connected to the front-end terminal of the next circuit board card via the rear-end terminal; the transmission line generally includes a power supply line and a data line, such as the power supply line and data line of a USB.

[0026] A first capacitor network is connected to the front-end terminal of each circuit board card, and a second capacitor network is connected to the rear-end terminal of each circuit board card.

[0027] Based on the above circuit structure, the first capacitor network shapes and filters the signal waveform input to the circuit board card before entering the board card circuit, and the second capacitor network shapes and filters the output signal waveform before outputting it to the next circuit board card.

[0028] As in the technical solution of the above-mentioned embodiment, the characteristics of capacitor filtering and voltage not being able to change suddenly are fully utilized. On the one hand, a capacitor network is set at the front end of the circuit board card to make the power supply and data transmission signals relatively stable. On the other hand, in view of the cascade characteristics of each circuit board card of the infrared touch frame, the power lines of the head and tail circuit boards are relatively long, and a capacitor network is also set at the rear end of each circuit board card, so that the capacitor network of the circuit board card is distributed at the front and rear ends of the circuit board card, reducing the energy of its electromagnetic interference radiation, improving the stability of the power supply and data transmission at the rear end of the circuit board card, ensuring the consistency and stability of the infrared touch frame, and being better compatible with various types of upper system terminals, and also improving the compatibility and reliability of the infrared touch frame.

[0029] In order to make the technical solution of the present application more clear, more detailed embodiments are described below.

[0030] refer to Figure 3 As shown, Figure 3It is a schematic diagram of the circuit structure of an infrared touch frame of an embodiment. The circuit board card may include a main board card and multiple slave boards. The front end terminal of the main board card is connected to the upper system end through a power supply line and a data line. The power supply line includes a positive power line and a negative power line. The data line includes a positive data line connected between two data positive electrodes and a negative data line connected between two data negative electrodes.

[0031] The data line uses differential signals to transmit data, such as the differential data interface D+ / D- of the USB transmission line. The back-end terminal of the main board is connected to the front-end terminal of the slave board through the power supply line. Multiple slave boards are cascaded and connected to the main board through the power supply line. The positive pole of the power supply is connected to the positive connection terminal through the positive power line, and the negative pole of the power supply is connected to the negative connection terminal through the negative power line.

[0032] In one embodiment, for the circuit structure design of the mainboard card, the first capacitor network on the mainboard card includes a plurality of capacitors connected in parallel between the positive power supply and the negative power supply, and the second capacitor network on the mainboard card includes a plurality of capacitors connected in parallel between the positive power connection terminal and the negative power connection terminal. Figure 3 In the embodiment, the first capacitor network of the mainboard card includes capacitors C1, C2, ..., C n These capacitors are connected to the front end of the motherboard card after the positive pole of the power supply enters the motherboard card. The second capacitor network of the motherboard card includes C n+1 , ...C n+n Etc. These capacitors are connected to the positive power pole at the rear end of the motherboard card near the positive power connection terminal of the next-level slave card, where the subscript "n" represents the digital number of the capacitor.

[0033] In one embodiment, the front-end terminals of the mainboard card include a pair of positive power poles and negative power poles and a pair of positive data poles and negative data poles; the rear-end terminals of the mainboard card include a pair of positive power connection terminals and negative power connection terminals, the positive power pole and negative power pole of the mainboard card are connected to the positive power pole and negative power pole of the upper system end through the positive power line and the negative power line respectively, the data positive pole D+ and the data negative pole D- of the mainboard card are connected to the data positive pole D+ and the data negative pole D- of the upper system end through the positive data line and the negative data line respectively, and a series resistor is also connected to the data line, wherein the series resistor can be a resistor group composed of multiple resistors connected in series; the data positive line and the data negative line at the front end of the series resistor are connected to the negative power line through a third capacitor network; the data positive line and the data negative line at the rear end of the series resistor are connected to the negative power line through a fourth capacitor network.

[0034] Exemplarily, the third capacitor network of the mainboard card may include at least one capacitor connected between the data positive line and the power negative line and at least one capacitor connected between the data negative line and the power negative line; similarly, the fourth capacitor network of the mainboard card may include at least one capacitor connected between the data positive line and the power negative line and at least one capacitor connected between the data negative line and the power negative line. Figure 3 In the embodiment, the third capacitor network of the mainboard card includes a capacitor C connected between the data positive line and the power negative line. U1 And the capacitor C connected between the data negative line and the power negative line U2 The fourth capacitor network of the motherboard card includes a capacitor C connected between the data positive line and the power negative line. U3 And the capacitor C connected between the data negative line and the power negative line U4 .

[0035] It should be noted that the above embodiment is only one of the combinations of capacitors and series resistors of the data line, and can be adjusted according to needs during specific implementation. For example, the positions of the series resistors and the capacitor network (the third capacitor network and the fourth capacitor network) can be interchanged.

[0036] As in the above embodiment, the circuit structure design of the series resistor and the third capacitor network and the fourth capacitor network can shape and filter the waveform of the signal through the resistor and capacitor before transmission, thereby ensuring the stability of the data signal transmitted between the main board card and the upper system end, reducing electromagnetic radiation interference, and improving the performance of the infrared touch frame.

[0037] In one embodiment, continue to refer to Figure 3 For the circuit structure design of the slave board, the slave board includes a transmitting board and a receiving board; wherein, multiple transmitting boards are cascaded connected through power supply lines and are respectively connected to the positive power connection terminal and the negative power connection terminal of the main board, and multiple receiving boards are cascaded connected through power supply lines and are connected to the positive power connection terminal and the negative power connection terminal of the main board.

[0038] The first capacitor network of the slave card may include a plurality of capacitors connected in parallel between the positive power supply and the negative power supply; the second capacitor network of the slave card may include a plurality of capacitors connected in parallel between the positive power connection terminal and the negative power connection terminal.

[0039] Exemplarily, the slave board includes N cascaded transmitting boards and M cascaded receiving boards; N≥2, M≥2, wherein N=M or M=N-1.

[0040] For the transmitter card, the first to N-1th level transmitter cards are provided with a first capacitor network connected to the positive power connection terminal and the negative power connection terminal of the transmitter card, and a second capacitor network connected to the positive power connection terminal and the negative power connection terminal of the transmitter card; the Nth level transmitter card is provided with a first capacitor network connected to the positive power connection terminal and the negative power connection terminal of the transmitter card; for example, Figure 3 The first capacitor network of the first to N-1th level transmitting cards includes capacitors C T11 , C T12 ,……,C T1j These capacitors are connected to the front end of the power supply positive electrode of the transmitter card after entering the transmitter card. The second capacitor network of the transmitter card includes C T1j+1 , ...C T1j+j These capacitors are connected to the positive power supply of the rear end of the transmitter card near the positive connection terminal of the next level transmitter card; the first capacitor network of the Nth level transmitter card includes capacitor C TN1 , C TN2 ,……,C TNj These capacitors are connected to the front end of the positive pole of the power supply of the transmitter card after it enters the transmitter card, where the subscript "T" represents the transmitter card, the subscript "N" represents the number of the transmitter card, and the subscript "j" represents the number of the capacitor.

[0041] For the receiving card, the first to M-1th level receiving cards are provided with a first capacitor network connected to the positive and negative connection terminals of the receiving card, and a second capacitor network connected to the positive and negative connection terminals of the receiving card; the Mth level receiving card is provided with a first capacitor network connected to the positive and negative connection terminals of the receiving card. For example, Figure 3 The first capacitor network of the first to M-1th level receiving cards includes capacitors C R11 , C R12 ,……,C R1i These capacitors are connected to the front end of the receiving card after the positive electrode of the power supply enters the receiving card. The second capacitor network of the receiving card includes C R1i+1 , ...C R1i+i These capacitors are connected to the positive power supply of the rear end of the receiving card near the positive connection terminal of the next-level receiving card; the first capacitor network of the M-th level receiving card includes capacitor C RM1 , C RM2 ,……,C RMi These capacitors are connected to the front end of the receiving board after the positive pole of the power supply enters the receiving board. The subscript "R" represents the receiving board, the subscript "M" represents the number of the receiving board, and the subscript "i" represents the number of the capacitor.

[0042] In one embodiment, the board circuit may include a control circuit and an infrared lamp, wherein the infrared lamp is a transmitting lamp or a receiving lamp. Exemplarily, the main board may also be integrated with a transmitting lamp, and the control circuit of the main board is responsible for controlling each transmitting board and receiving board.

[0043] Exemplarily, the capacitors used in the first capacitor network, the second capacitor network, the third capacitor network, and the fourth capacitor network of the present application may be ceramic capacitors, electrolytic capacitors, tantalum capacitors, and other capacitor types.

[0044] As in the technical solutions of the above-mentioned embodiments, a capacitor network is used to balance the stability and reliability of data signals and power supply, reduce data loss or damage caused by interference with data signals, reduce the radiation energy of electromagnetic interference, reduce the fluctuation of the power supply of the infrared touch frame, and ensure the consistency and stability of the power supply of the head and tail boards; by adding a corresponding capacitor network, only a very small increase in hardware cost is required, which can reduce the cost of secondary design and development caused by the instability brought by the upper system end and the use of some special devices, such as common-mode inductors and other devices, which can reduce the overall hardware cost of the infrared touch frame and improve the design compatibility and reliability of the infrared touch frame.

[0045] The following describes embodiments of an infrared touch frame and an infrared touch screen.

[0046] The infrared touch frame provided in the present application includes the circuit structure of the infrared touch frame provided in this embodiment; Figure 4 As shown, Figure 4 The infrared touch frame structure diagram of an embodiment includes a main board card and a plurality of connected slave boards, each of which is connected to the main board card through a power supply line and a data line. In the figure, the main board card is connected to slave boards ①, ②, ..., ⑧ through data lines. The main board card is integrated on the slave board ⑧, and of course, an independent main board card can also be designed. Slave boards ①, ②, ③ and ⑧ are transmitting boards, and slave boards ④, ⑤, ⑥ and ⑦ are receiving boards.

[0047] In addition, the infrared touch screen provided in the present application includes a display screen and the above-mentioned infrared touch frame.

[0048] The infrared touch frame and infrared touch screen mentioned above can improve the stability of the power supply system and data transmission of the infrared touch frame, reduce the energy of its electromagnetic interference radiation, ensure the consistency and stability of the infrared touch frame, and can better be compatible with various types of upper system terminals, thereby improving the compatibility and reliability of the infrared touch frame.

[0049] It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as those generally understood by those skilled in the art to which this application belongs. It should also be understood that terms such as those defined in general dictionaries should be understood to have meanings consistent with those in the context of the prior art, and will not be interpreted with idealized or overly formal meanings unless specifically defined as here.

[0050] The above description is only a partial implementation method of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A circuit structure of an infrared touch frame, characterized in that: include: A plurality of circuit board cards connected in cascade; wherein the circuit board cards are provided with front-end terminals, card circuits and rear-end terminals in sequence; Each circuit board card is cascade-connected through a transmission line, and the upper circuit board card is connected to the front-end terminal of the next circuit board card through the rear-end terminal; A first capacitor network is connected to the front end terminal of each circuit board card, and a second capacitor network is connected to the rear end terminal of each circuit board card; The first capacitor network shapes and filters the signal waveform input to the circuit board card before it enters the board card circuit, and the second capacitor network shapes and filters the output signal waveform before it is output to the next circuit board card.

2. The circuit structure of the infrared touch frame according to claim 1, characterized in that: The circuit board card comprises: a main board card and a plurality of slave boards; The transmission line includes: a power supply line and a data line; The front-end terminal of the main board is connected to the upper system terminal through a power supply line and a data line, and the rear-end terminal of the main board is connected to the front-end terminal of the slave board through a power supply line; wherein a plurality of slave boards are cascade-connected and connected to the main board through a power supply line; The first capacitor network of the mainboard card includes a plurality of capacitors connected in parallel between the positive power supply and the negative power supply; the second capacitor network of the mainboard card includes a plurality of capacitors connected in parallel between the positive power connection terminal and the negative power connection terminal.

3. The circuit structure of the infrared touch frame according to claim 2, characterized in that: The front-end terminal of the mainboard card includes a pair of positive power supply electrodes and negative power supply electrodes and a pair of positive data electrodes and negative data electrodes; The rear end terminals of the mainboard card include a pair of positive electrical connection terminals and a negative electrical connection terminal; The positive power electrode and the negative power electrode of the mainboard card are connected to the positive power electrode and the negative power electrode of the upper system end through the positive power line and the negative power line respectively; The data positive electrode and data negative electrode of the mainboard card are connected to the data positive electrode and data negative electrode of the upper system end through a data positive line and a data negative line respectively, and are also connected with a series resistor; The data positive line and the data negative line at the front end of the series resistor are connected to the power negative line through a third capacitor network; The data positive line and the data negative line at the rear end of the series resistor are connected to the power negative line through a fourth capacitor network.

4. The circuit structure of the infrared touch frame according to claim 3, characterized in that: The third capacitor network of the mainboard card includes: at least one capacitor connected between the data positive line and the power negative line and at least one capacitor connected between the data negative line and the power negative line; The fourth capacitor network of the mainboard card includes: at least one capacitor connected between the data positive line and the power negative line and at least one capacitor connected between the data negative line and the power negative line.

5. The circuit structure of the infrared touch frame according to claim 2, characterized in that: The first capacitor network of the slave card includes a plurality of capacitors connected in parallel between the positive power supply and the negative power supply; the second capacitor network of the slave card includes a plurality of capacitors connected in parallel between the positive power connection terminal and the negative power connection terminal.

6. The circuit structure of the infrared touch frame according to claim 5, characterized in that: The slave board includes: a transmitting board and a receiving board; wherein, a plurality of transmitting boards are cascade-connected through power supply lines and are respectively connected to the positive power connection terminal and the negative power connection terminal of the main board, and a plurality of receiving boards are cascade-connected through power supply lines and are connected to the positive power connection terminal and the negative power connection terminal of the main board.

7. The circuit structure of the infrared touch frame according to claim 6, characterized in that: The slave boards include: N cascaded transmitting boards and M cascaded receiving boards; N≥2, M≥2; wherein, The first to N-1th level transmitting cards are provided with a first capacitor network connected to the positive and negative power connection terminals of the transmitting card, and a second capacitor network connected to the positive and negative power connection terminals of the transmitting card; the Nth level transmitting card is provided with a first capacitor network connected to the positive and negative power connection terminals of the transmitting card; The first to M-1 level receiving boards are provided with a first capacitor network connected to the positive power connection terminal and the negative power connection terminal of the receiving board, and a second capacitor network connected to the positive power connection terminal and the negative power connection terminal of the receiving board; the M level receiving board is provided with a first capacitor network connected to the positive power connection terminal and the negative power connection terminal of the receiving board.

8. The circuit structure of the infrared touch frame according to claim 1, characterized in that: The board circuit includes a control circuit and an infrared lamp tube; wherein the infrared lamp tube is a transmitting lamp tube or a receiving lamp tube.

9. An infrared touch frame, characterized in that: include: The circuit structure of the infrared touch frame according to any one of claims 1 to 8.

10. An infrared touch screen, characterized in that: include: A display screen and the infrared touch frame as claimed in claim 9.

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