Infrared touch frame circuit board card, infrared touch frame and infrared touch screen

Abstract

The present application relates to an infrared touch frame circuit board, an infrared touch frame and an infrared touch screen. The infrared touch frame circuit board includes a main board and multiple slave boards. The main board is provided with a signal attenuation circuit, and the slave board is provided with a signal restoration circuit. The main board and each slave board are connected through a signal bus. The main board sends a control signal to each slave board through the signal bus to control an infrared lamp tube for scanning. The signal attenuation circuit attenuates the control signal and then sends it to the slave board, and the slave board restores the control signal to a strong signal for processing through the signal restoration circuit. The slave board loads the analog signal collected by the infrared lamp tube onto the signal bus and transmits it to the main board, and the main board extracts the analog signal from the signal bus and uses it for touch positioning. This technical solution reduces the interference effect of the control signal on the analog signal, improves the sampling quality of the infrared light signal, improves the frame rate of the infrared scanning, and improves the performance of the infrared touch frame.

Description

[0001] This application claims the priority of the Chinese patent application filed with the China Patent Office on February 9, 2024, with application number 2024101786462 and invention name “Infrared touch frame circuit board card, infrared touch frame and infrared touch screen”, all contents of which are incorporated by reference in this application. Technical Field

[0002] The present application relates to the field of infrared touch technology, and in particular to an infrared touch frame circuit board card, an infrared touch frame and an infrared touch screen. Background Art

[0003] In the infrared touch frame, multiple groups of infrared tubes are distributed and arranged around the display screen. The infrared transmitting tube is controlled to emit infrared light, and the infrared receiving tube is controlled to receive and convert the infrared light signal into an analog signal. A series of intensity adjustments are made to the infrared light signal, and then A / D sampling is performed on the infrared light signal. The infrared light signal is judged based on whether there is a change in the signal after adjustment and stabilization to determine whether there is an object blocking the infrared light, thereby judging the touch operation situation and calculating the corresponding position coordinate output, thereby realizing the click, line drawing, touch and other functions of the infrared touch frame.

[0004] In the touch positioning of the infrared touch frame, the quality of the infrared light signal directly affects the A / D sampling result and is reflected in the performance of the infrared touch frame, such as click accuracy, writing precision and line drawing effect. Since the analog signal converted by the infrared receiving tube after receiving the infrared light signal is a weak analog electrical signal, and the control signal for controlling the infrared light scanning in the touch frame is a strong digital signal, the data packet after A / D sampling of the infrared light signal on the circuit board card and the connecting line of the infrared touch frame contains the interference signal component of the control signal, thereby affecting the quality of the analog signal for A / D sampling of the infrared light signal, thereby affecting the performance of the infrared touch frame and the infrared touch screen. Summary of the invention

[0005] The purpose of the present application is to solve one of the above-mentioned technical defects and provide an infrared touch frame circuit board card, an infrared touch frame and an infrared touch screen to reduce signal crosstalk and improve the performance of the infrared touch frame circuit board card.

[0006] An infrared touch frame circuit board card, comprising: a main board and a plurality of slave boards; the main board is provided with a signal attenuation circuit, the slave boards are provided with a signal restoration circuit; the main board and the slave boards are connected via a signal bus;

[0007] The main board sends a control signal for controlling the infrared lamp to scan to each slave board through a signal bus; wherein the signal attenuation circuit attenuates the control signal and then sends it to the slave board, and the slave board restores the control signal to a strong signal for processing through a signal restoration circuit;

[0008] The slave board loads the analog signal collected by the infrared lamp onto the signal bus and transmits it to the host board. The host board extracts the analog signal from the signal bus and uses it for touch positioning.

[0009] An infrared touch frame comprises: the infrared touch frame circuit board card; wherein the slave board is connected to an infrared lamp array.

[0010] An infrared touch screen comprises: a display screen and the infrared touch frame; wherein the infrared touch frame is arranged around the display screen.

[0011] The technical solution of the present application is to attenuate the control signal by using a signal attenuation circuit on the main board before sending it to the slave board. When the slave board is in use, the signal restoration circuit restores the control signal to a strong signal before processing. At the same time, the slave board loads the analog signal converted from the infrared light signal onto the signal bus and transmits it back to the main board for centralized processing, thereby realizing the ability to simultaneously transmit the control signal and the analog signal on the same circuit board or line in the infrared touch frame, reducing the interference of the control signal on the analog signal, thereby improving the sampling quality of the infrared light signal and improving the performance of the infrared touch frame and the infrared touch screen. At the same time, each slave board transmits the analog signal back to the main board for centralized touch positioning processing, simplifying the processing flow of the infrared light signal on the slave board, reducing the complexity of the processing of the analog signal by each slave board, fast response speed, and improving the frame rate of infrared scanning.

[0012] 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

[0013] 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:

[0014] Figure 1 is a schematic diagram of the structure of an infrared touch frame circuit board card of an embodiment;

[0015] Figure 2 is a schematic diagram of the structure of an infrared touch frame according to an embodiment;

[0016] Figure 3 is a circuit structure diagram of a circuit board card of an embodiment;

[0017] Figure 4 is a schematic diagram of the structure of an infrared touch frame according to another embodiment;

[0018] Figure 5is a working sequence diagram of an infrared touch frame circuit board card of an embodiment;

[0019] Figure 6 The following is an example of a PWM synchronization signal diagram. DETAILED DESCRIPTION

[0020] 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.

[0021] 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.

[0022] The infrared touch frame circuit board card provided by the present application, in the use scenario of cascade connection of circuit board cards, since the infrared light signal is a weak analog signal, and the control signal for controlling the infrared light in the touch frame to scan is a strong digital signal, the weak analog signal and the strong digital signal exist on the same circuit board card or the same group of signal buses, and there is overlap in the working timing, and the control signal is likely to interfere with the collection of the infrared light signal. Accordingly, the present application sets a technical solution in the circuit board card that first attenuates the signal strength of the strong digital signal and then restores it, thereby avoiding the control signal from affecting the sampling quality of the infrared light signal when it is transmitted on the digital signal bus. At the same time, each slave board transmits the analog signal back to the host board for centralized processing, thereby simplifying the circuit structure of the slave board and improving the stability of the circuit board card.

[0023] refer to Figure 1 As shown, Figure 1 The present invention is a schematic diagram of the structure of an infrared touch frame circuit board card of an embodiment, wherein the circuit board card comprises a main board and a plurality of slave boards 1 to n, where n≥2; wherein the main board is connected to each slave board via a signal bus, and illustratively, as shown in the figure, the signal bus may comprise a digital signal bus and an analog signal bus; a signal attenuation circuit is provided on the main board, and a signal restoration circuit is provided on the main board.

[0024] The main board sends a control signal for controlling the infrared lamp to scan to each slave board through a digital signal bus. The infrared lamp includes an infrared receiving tube and an infrared receiving tube. The slave board will be installed with an infrared transmitting tube or an infrared receiving tube, which corresponds to a transmitting board or a receiving board respectively. The signal attenuation circuit attenuates the control signal, such as attenuating its intensity by N times before transmitting, and can be sent to each slave board through the digital signal bus. When used on the slave board, the control signal is restored to a strong signal through a signal restoration circuit, such as enhancing its intensity by M times before processing, and is used to control the infrared transmitting tube to transmit and the infrared receiving tube to scan and receive; the enhancement multiple of the control signal should at least meet the intensity requirement that the slave board can normally identify.

[0025] In order to better reduce the impact of crosstalk, the signal attenuation circuit is arranged after the control signal generating circuit of the main board to attenuate the generated control signal, and the signal restoration circuit is arranged near the circuit that needs to use the control signal.

[0026] The infrared receiving tubes on the slave boards receive infrared light signals. As shown in the figure, the infrared receiving tubes R on each slave board convert the infrared light signals into analog signal outputs. The slave boards load the analog signals onto the analog signal bus and transmit them back to the main board. The main board extracts the analog signals from the analog signal bus and then uses them for touch positioning.

[0027] In one embodiment, the control signal is a low voltage strong digital signal, and the analog signal is a weak analog electrical signal converted by an infrared receiving tube receiving an infrared light signal.

[0028] Since the infrared touch frame realizes the ability to transmit control signals and analog signals simultaneously on the same circuit board or line, the analog signal converted and output by the infrared receiving tube after receiving the infrared light signal can be directly transmitted back to the main board through the analog signal bus for A / D sampling. Each slave board shares the analog signal bus, and each slave board does not need to be provided with a corresponding sampling circuit. Compared with the conventional technical solution of performing analog-to-digital conversion on the slave board and then sending it to the main board, the solution of this embodiment reduces the processing link of converting to digital signals on the slave board, simplifies the processing flow of infrared light signals on the slave board, and greatly improves the efficiency of the control system. The circuit structure complexity of each slave board is reduced. Since the infrared light signal received by the infrared lamp has a large amount of data, it takes a long time to convert the digital signal into a digital signal. After the digital signal is converted, due to the large amount of data, it takes a long time to transmit it from the slave board to the main board through the digital signal bus. The digital signal bus from each slave board to the main board is long, which can easily lead to signal attenuation or distortion and increase the time consumption. By converting the infrared light signal received by the infrared lamp from an analog signal to a digital signal on the slave board, the circuit processing flow is simplified, and the analog signals of each slave board are concentrated on the main board for processing, thereby improving the response speed and the frame rate of infrared scanning.

[0029] refer to Figure 2 As shown, Figure 2 The infrared touch frame structure diagram of an embodiment is shown in the figure. The main board and the slave board are connected through a digital signal bus and an analog signal bus. As shown in the figure, the infrared touch frame circuit board includes slave boards ① to ⑧. The figure shows the connection circuit part between the main board and the slave board. The infrared lamp on the slave board can be an infrared transmitting tube and / or an infrared receiving tube. Generally, an infrared transmitting tube or an infrared receiving tube is installed on each circuit board. When the infrared transmitting tube is installed, the slave board is a transmitting board, and when the infrared receiving tube is installed, the slave board is a receiving board. Each slave board shares the analog signal bus. For the main board, it can be connected to the slave board as a separate circuit board, or it can be integrated into any slave board and share a circuit board card with the slave board. As shown in the figure, the main board is integrated into the slave board ⑧. If the main board is a separate circuit board card, the infrared lamp is not set on the main board.

[0030] In one embodiment, the signal attenuation circuit may include a passive attenuation circuit or an active attenuation circuit, which may be determined according to the use requirements of this patent.

[0031] In one embodiment, the signal restoration circuit may include a common-mode amplifier circuit, an inverting amplifier circuit, a triode amplifier circuit or a comparator circuit, etc., which may be determined according to the use requirements of this patent.

[0032] In one embodiment, Figure 3 As shown, Figure 3 The present invention is a circuit structure diagram of a circuit board card of an embodiment, showing some circuit elements of a main board. The main board in the figure includes a signal conditioning circuit, an A / D sampling circuit and a main MCU (Microprocessor Control Unit) connected in sequence, wherein the signal conditioning circuit is connected to an analog signal bus, the main MCU is connected to a digital signal bus through a signal attenuation circuit, a slave MCU is provided on the slave board, an infrared transmitting tube or an infrared receiving tube is connected to the slave board, and the slave MCU is connected to the digital signal bus through a signal restoration circuit.

[0033] Each slave board is configured with a hardware address. The master MCU and each slave MCU can transmit data through address recognition. The master MCU can control the slave MCUs of each slave board to perform scanning through a digital signal bus.

[0034] Exemplarily, the control signal may include scanning data. The working principle of the infrared touch frame circuit board card of the above-mentioned embodiment structure may be as follows: before the scanning starts, the main MCU of the host board sends the scanning data to the slave MCU of each slave board through the digital signal bus. After each slave MCU receives its own scanning data, it stores it. When executing the scanning of the infrared lamp tube, the slave MCU of each slave board reads the scanning data and performs the scanning according to the scanning data. Normally, the scanning data includes the position information of the infrared receiving tube and the infrared transmitting tube connected to the slave board and the corresponding scanning logic, etc.

[0035] In one embodiment, Figure 4 As shown, Figure 4 1 is a schematic diagram of the structure of an infrared touch frame according to another embodiment. The figure only shows the circuit part related to the embodiment. In the infrared touch frame, a digital signal bus, an analog signal bus and a synchronous signal bus are included between the main board and multiple slave boards.

[0036] When multiple slave boards of the infrared touch frame perform infrared scanning, since different slave boards are responsible for infrared lamps at different positions, in order to distinguish different scanned data, when the main MCU of the host board communicates with the slave MCU of the slave board, data transmission between devices that need to communicate is realized based on the address recognition method. For example, before the scanning starts, the host board sends different scanned data to the corresponding slave boards based on the address recognition method; accordingly, each slave board is configured with a hardware address, and the use of the hardware address can unify the firmware of all slave boards, and facilitate the firmware upgrade of the slave boards, and only one firmware is needed for all slave boards.

[0037] In one embodiment, the working sequence of the infrared touch frame circuit board card of the present application is as follows: Figure 5 As shown, Figure 5This is a working sequence diagram of an infrared touch frame circuit board card of an embodiment.

[0038] Before scanning starts, the main MCU of the host board sends the scanning data to the slave MCUs of each slave board through the digital signal bus. Each slave MCU stores the scanning data after receiving it. After scanning starts, when the slave MCUs of each slave board execute the scanning of the infrared lamp tube, the main MCU sends a synchronization signal to the slave MCU through the synchronization signal bus. After receiving the synchronization signal, the slave MCU parses it, reads the stored scanning data and performs scanning according to the scanning data. The scanning data includes the position information of the infrared receiving tube and the infrared transmitting tube installed on the slave board and the corresponding scanning logic. The slave board directly loads the analog signal output by the infrared receiving tube to the analog signal bus and transmits it to the host board. The signal conditioning circuit detects the analog signal from the analog signal bus and amplifies and conditions it. The A / D sampling circuit performs A / D sampling on the amplified analog signal to obtain a digital signal and transmits it back to the main MCU. The main MCU analyzes and processes the digital signal to calculate the coordinate position of the touch object, or uploads it to the host computer to calculate the coordinate position of the touch object.

[0039] As in the above embodiment, the main MCU uses a separate synchronization signal bus to transmit the synchronization signal to the slave MCU, wherein the synchronization signal bus can be connected between the signal attenuation circuit and the signal restoration circuit. The main MCU attenuates the synchronization signal through the signal attenuation circuit and then restores it through the amplification and restoration circuit before inputting it into the slave MCU, thereby reducing the impact on the analog signal. The slave MCU controls the corresponding infrared lamp tube for scanning through the synchronization signal.

[0040] In one embodiment, the synchronization signal may be a PWM synchronization signal; wherein the PWM synchronization signal is provided with a start signal of a synchronization scan and a PWM pulse signal; Figure 6 As shown, Figure 6 This is an example schematic diagram of a PWM synchronization signal, in which the pulse width of the start signal is different from the PWM pulse width of the switch light. As shown in the figure, the pulse width of the start signal is τ1, the PWM pulse width of the switch light is τ2, and the time interval between the two is τ3. The time interval τ3 is used to wait for the slave board to complete the start signal analysis and the buffer time to complete the scan data preparation, so as to facilitate the synchronization of each slave host to start scanning control; wherein, τ1, τ2, τ3 are set time widths, for example, τ1 = 4us, τ2 = 0.5us, τ3 = 59.35us; after the main board transmits the PWM synchronization signal to the slave host, the slave host parses the data of the PWM synchronization signal in real time and starts a frame scan when the start signal is recognized.

[0041] As in the above-mentioned embodiment, through the design of the start signal structure with different pulse widths and the signal analysis technology solution, the main board can drive all the slave boards to scan through a PWM synchronization signal, thus avoiding complex control logic.

[0042] In one embodiment, for the signal attenuation circuit of the main board, its attenuation multiple can be set before use. For example, the signal attenuation circuit can be set to attenuate the control signal N times to obtain an attenuated signal. At the same time, for the signal restoration circuit of the slave board, its amplification multiple can also be set before use. For example, the signal restoration circuit can be set to amplify the attenuated signal M times to obtain a strong signal to meet the use requirements. For the signal attenuation circuit with a set attenuation multiple and the signal restoration circuit with a set amplification multiple, the attenuated signal obtained from the control signal and the weak analog signal obtained from the infrared light signal can be transmitted on the same board without interfering with each other.

[0043] In order to enable the infrared touch frame circuit board to be used in different scenarios, in one embodiment, the attenuation multiple of the signal attenuation circuit of the main board can also be dynamically set; the main board can obtain the first strength of the control signal and detect the second strength of the analog signal at the same time, and then calculate the attenuation multiple N of the signal attenuation circuit according to the first strength and the second strength and set it.

[0044] Specifically, the maximum strength of the attenuated signal during common board transmission can be determined according to the second strength, and the attenuation factor N of the signal attenuation circuit can be calculated and dynamically set in combination with the maximum strength of the attenuated signal and the first strength of the control signal; at the same time, the amplification factor of the signal restoration circuit of the slave board can also be dynamically set. Since the slave board needs to meet certain strength requirements when using the amplified and restored synchronization signal, the signal restoration circuit amplifies the attenuated signal M times to obtain a strong signal. The amplification factor M can be calculated and dynamically set in combination with the actual strength of the attenuated signal and the minimum strength required by the slave board.

[0045] As in the above-mentioned embodiment, by dynamically setting the attenuation multiple N and the amplification multiple M, the infrared touch frame circuit board can be used in different scenarios, ensuring the stability of strong digital signals and analog signals when transmitted on the same board, and improving the function of the infrared touch frame.

[0046] The following describes embodiments of an infrared touch frame and an infrared touch screen.

[0047] The infrared touch frame of this embodiment includes a main board and multiple slave boards, wherein each slave board is connected to an infrared lamp array. The main board and each slave board can be connected via a signal bus. Exemplarily, the signal bus can include a digital signal bus and an analog signal bus, and can also include a synchronous signal bus.

[0048] The infrared touch frame of the above-mentioned embodiment adopts the infrared touch frame circuit board card of any of the above-mentioned embodiments, which reduces the interference of the control signal on the analog signal, thereby improving the sampling quality of the infrared light signal, simplifying the processing flow of the infrared light signal on the slave board, reducing the complexity of each slave board in processing the analog signal, and having a fast response speed, thereby improving the frame rate of the infrared scan.

[0049] An embodiment of the infrared touch screen is described below.

[0050] The infrared touch screen of this embodiment includes a display screen and an infrared touch frame; wherein the infrared touch frame is arranged around the display screen. As in the infrared touch screen of the above embodiment, the infrared touch frame of the above embodiment is adopted to reduce the interference of the control signal on the analog signal, thereby improving the sampling quality of the infrared light signal, simplifying the processing flow of the infrared light signal on the slave board, reducing the complexity of each slave board in processing the analog signal, and having a fast response speed, thereby improving the frame rate of the infrared scan.

[0051] 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.

[0052] 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. An infrared touch frame circuit board card, comprising: A main board and a plurality of slave boards; characterized in that the main board is provided with a signal attenuation circuit, and the slave boards are provided with a signal restoration circuit; the main board and the slave boards are connected via a signal bus; wherein the signal bus includes a synchronous signal bus; The main board sends a control signal for controlling the infrared lamp to scan to each slave board through a synchronous signal bus; wherein the control signal includes a synchronous signal, the signal attenuation circuit attenuates the control signal and then sends it to the slave board, and the slave board restores the control signal to a strong signal for processing through a signal restoration circuit; The slave board loads the analog signal collected by the infrared lamp onto the signal bus and transmits it to the host board. The host board extracts the analog signal from the signal bus and uses it for touch positioning.

2. The infrared touch frame circuit board card according to claim 1, characterized in that: The signal bus also includes a digital signal bus and an analog signal bus; The main board also sends a control signal to each slave board through a digital signal bus; wherein the control signal includes scan data; The slave board loads the analog signal onto the analog signal bus and transmits it to the host board, and the host board extracts the analog signal from the analog signal bus.

3. The infrared touch frame circuit board card according to claim 2, characterized in that: The main board also includes: a signal conditioning circuit, an A / D sampling circuit and a main MCU connected in sequence; wherein the signal conditioning circuit is connected to the analog signal bus, and the main MCU is connected to the digital signal bus through a signal attenuation circuit; The slave board is also provided with a slave MCU, wherein the slave MCU is connected to the digital signal bus via a signal restoration circuit.

4. The infrared touch frame circuit board card according to claim 2, characterized in that: The control signal is a low voltage strong digital signal, and the control signal includes scanning data; wherein the main board sends the scanning data to each slave board through a digital signal bus.

5. The infrared touch frame circuit board card according to claim 4, characterized in that: The infrared lamp tube comprises an infrared transmitting tube and an infrared receiving tube; The analog signal is a weak analog electrical signal converted by the infrared receiving tube when receiving the infrared light signal.

6. The infrared touch frame circuit board card according to claim 2, characterized in that: The master MCU sends a synchronization signal to each slave MCU via a synchronization signal bus to trigger the infrared lamp to perform scanning using the scanning data.

7. The infrared touch frame circuit board card according to claim 6, characterized in that: The synchronization signal is a PWM synchronization signal, wherein a start signal of a synchronization scan and a PWM pulse signal are provided in the PWM synchronization signal.

8. The infrared touch frame circuit board card according to claim 1, characterized in that: The signal attenuation circuit includes a passive attenuation circuit or an active attenuation circuit.

9. The infrared touch frame circuit board card according to claim 2, characterized in that: The signal restoration circuit includes a common-phase amplifier circuit, an inverting amplifier circuit, a triode amplifier circuit or a comparator circuit.

10. An infrared touch frame, characterized in that: include: The infrared touch frame circuit board card according to any one of claims 1 to 9; wherein the slave board is connected to an infrared lamp array.

11. An infrared touch screen, characterized in that: include: A display screen and the infrared touch frame as claimed in claim 10; wherein the infrared touch frame is arranged around the display screen.

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