Infrared touch frame and infrared touch screen

Abstract

The utility model relates to an infrared touch frame and an infrared touch screen, the infrared touch frame comprises a mainboard and a plurality of slave boards, the mainboard is in cascade connection with the slave boards through connecting lines, the mainboard is connected with the slave boards through signal buses, and the signal buses comprise a digital signal bus and an analog signal line; the mainboard is provided with a signal attenuation circuit, and the slave board is provided with a signal reduction circuit. The signal attenuation circuit is connected with the signal reduction circuit through a digital signal bus; the main board outputs a strong digital signal to the signal attenuation circuit for attenuation, and the strong digital signal is transmitted to the signal reduction circuit on the slave board through the digital signal bus to be reduced into the strong digital signal for use; the slave board transmits the weak analog signal back to the mainboard for centralized processing through the analog signal bus; according to the technical scheme, the interference of strong digital signals on weak analog signals is reduced, the processing complexity of each slave board on the analog signals is reduced, the response speed is high, and the performance of the infrared touch frame is improved.

Description

[0001] This application claims priority to a Chinese patent application filed with the China Patent Office on February 9, 2024, with application number 202420292567X and invention name “Communication device, circuit board card, infrared touch frame and infrared touch screen”, the entire 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 and an infrared touch screen. Background Art

[0003] In some circuit boards, it is usually necessary to connect with other circuit boards. Signals of different strengths are transmitted and processed between the circuit boards. These signals of different strengths are on the same circuit board or connecting line, and there will be certain intersections in the working timing. Weak signals are easily interfered by strong signals. Since they cannot be avoided in timing, the quality of the weak signals is directly affected, so that the weak signals contain interference signal components, which easily affect the performance of the circuit board.

[0004] In the infrared touch frame, positioning is performed by arranging multiple groups of infrared pairs of tubes on circuit boards distributed around the infrared touch frame to transmit and receive infrared light signals. Since the infrared light signal is a weak analog signal, and the control signal for controlling the scanning of the infrared light in the touch frame is a strong digital signal, the data after A / D sampling of the infrared light signal on the circuit board and signal bus of the infrared touch frame contains interference signal components of the control signal, thereby affecting the quality of A / D sampling and thus affecting the performance of the infrared touch frame. Utility Model Content

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

[0006] An infrared touch frame comprises a main board and a plurality of slave boards, wherein the main board and the slave boards are cascade-connected via connecting wires; the main board and the slave boards are connected via a digital signal bus, and the main board and the slave boards are connected via an analog signal bus;

[0007] The host board is provided with a signal attenuation circuit, and the slave board is provided with a signal restoration circuit; the signal attenuation circuit and the signal restoration circuit are connected via a digital signal bus;

[0008] The main board outputs a strong digital signal to the signal attenuation circuit for attenuation, and transmits it to the signal restoration circuit on the slave board through the digital signal bus to restore it to a strong digital signal for use;

[0009] The slave board transmits the weak analog signal back to the host board through the analog signal bus for centralized processing.

[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 this application has the following beneficial effects:

[0012] (1) The strong digital signal is first attenuated into a weak analog signal for transmission, thereby reducing the intersection of the strong digital signal and the weak analog signal on the transmission line, thereby reducing the interference of the strong digital signal on the weak analog signal.

[0013] (2) Each slave board transmits the analog signal back to the host board for centralized touch positioning processing, which simplifies the processing flow of infrared light signals on the slave board, reduces the complexity of analog signal processing by each slave board, improves the response speed, increases the frame rate of infrared scanning, and improves the performance of the infrared touch frame.

[0014] 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

[0015] 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:

[0016] Figure 1 is a structural block diagram of an infrared touch frame of an embodiment;

[0017] Figure 2 is a schematic diagram of the circuit board structure of an infrared touch frame according to an embodiment;

[0018] Figure 3 is a circuit structure diagram of a master board and a slave board of an embodiment;

[0019] Figure 4 is a structural block diagram of an infrared touch frame according to another embodiment;

[0020] Figure 5 is a circuit structure diagram of a host board and a slave board of another embodiment;

[0021] Figure 6 The following is an example of a PWM synchronization signal diagram. DETAILED DESCRIPTION

[0022] 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.

[0023] 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.

[0024] In the infrared touch frame, since the analog electrical signal converted from 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 or analog signal bus, and have an intersection in timing, resulting in signal crosstalk, which affects the sampling quality of the infrared light signal.

[0025] Accordingly, the present application provides an infrared touch frame, such as Figure 1 As shown, Figure 1 The structure diagram of an infrared touch frame of an embodiment includes a main board and multiple slave boards. The main board and each slave board are cascade-connected through connecting lines. The main board and the slave boards are connected through a signal bus. The signal bus includes a digital signal bus and an analog signal line connection. Figure 1 In the figure, the infrared touch frame includes slave boards ① to ⑧, wherein the slave boards are connected to infrared lamps; a digital signal bus and an analog signal bus are connected between the main board and the slave boards, and 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. The example shown in the figure is that 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.

[0026] In a specific implementation, the slave board may include a receiving board and a transmitting board; the transmitting board is connected to the infrared transmitting tube, and the receiving board is connected to the infrared receiving tube, wherein the host board is connected to the receiving board and the transmitting board through a digital signal bus, and the host board is connected to each receiving board through an analog signal bus.

[0027] refer to Figure 2 As shown, Figure 2The present invention is a schematic diagram of the circuit board structure of an infrared touch frame of an embodiment, wherein a main board and slave boards 1 to n (n≥2) are cascaded, a signal attenuation circuit is provided on the main board, and a signal restoration circuit is provided on the slave board, and the signal attenuation circuit and the signal restoration circuit are connected through a digital signal bus; illustratively, for the signal attenuation circuit, it may include a passive attenuation circuit or an active attenuation circuit; for the signal restoration circuit, it may include a common-phase amplifier circuit, an inverting amplifier circuit, a triode amplifier circuit or a comparator circuit, etc.

[0028] In application, the main board outputs a strong digital signal to the signal attenuation circuit for attenuation, which is transmitted to the signal restoration circuit on the slave board through the digital signal bus and restored to a strong digital signal for use; illustratively, the strong digital signal can be a control signal for the main board to control the infrared lamp of the slave board to scan; specifically, the signal attenuation circuit attenuates the strong digital signal by N times to obtain an attenuated digital signal, the attenuated digital signal is transmitted to the slave board through the digital signal bus, and the signal restoration circuit amplifies the attenuated digital signal by M times to obtain a strong digital signal that can be used by the slave board.

[0029] The technical solution of the above-mentioned embodiment is applicable to the situation where strong digital signals and weak analog signals exist simultaneously in the infrared touch frame circuit board and signal bus. The weak analog signal on the same circuit board or signal bus is easily interfered by the strong digital signal, so that the weak analog signal will contain interference signal components when AD sampling is performed. The infrared touch frame of this embodiment first attenuates the signal strength of the strong digital signal, and then restores it when used, so as to avoid affecting the sampling quality of the analog signal when the control signal is transmitted on the circuit board or on the signal bus, thereby improving the stability of the infrared touch frame.

[0030] In a specific implementation, the above-mentioned weak analog signal can be an analog electrical signal. The infrared receiving tube connected to the receiving board receives the infrared light signal emitted by the infrared transmitting tube and converts the infrared light signal into an analog electrical signal. The receiving board transmits the analog electrical signal back to the main board through the analog signal bus for centralized processing.

[0031] As in the technical solution of the above-mentioned embodiment, each receiving board shares an analog signal bus, and each receiving board converts the collected infrared light signal into a weak analog signal, directly loads it on the analog signal bus and transmits it back to the host board for centralized amplification and A / D sampling processing, thereby reducing the processing circuits for amplification and conversion into digital signals set on the slave board, reducing the circuit structure complexity of the slave board, improving the response speed, and improving the frame rate of infrared scanning.

[0032] In one embodiment, for the structure of the host board and the slave board of the infrared touch frame, as shown in FIG. Figure 3 As shown, Figure 3The present invention is a circuit structure diagram of a main board and a slave board of an embodiment, showing some circuit elements. The main board is connected in sequence with a signal conditioning circuit, an A / D sampling circuit, a main MCU (Microprocessor Control Unit) and a signal attenuation circuit; the signal conditioning circuit is connected to an analog signal bus, and the main MCU is connected to a digital signal bus through a signal attenuation circuit; a slave MCU and a signal restoration circuit are provided on a transmitting board and a receiving board, and the slave MCU is connected to the digital signal bus through the signal restoration circuit.

[0033] For example, for the analog signal bus, it may include multiple parallel signal channels. When the infrared receiving tube adopts the group scanning mode, since there will be multiple infrared receiving tubes outputting analog electrical signals at the same time, each signal channel can transmit the analog signal to the main board at the same time. The slave MCU can control the connected infrared transmitting tube and infrared receiving tube to perform scanning. The master MCU and the slave MCU perform data transmission based on the address recognition mode, and each slave board is configured with a hardware address.

[0034] Before the scan starts, the main MCU of the host board sends the scan data as a control signal to the slave MCU of each slave board through the digital signal bus. Each slave MCU stores the scan data after receiving it. When the receiving board slave MCU of each slave board scans the infrared lamp, it reads the scan data and performs the scan according to the scan data.

[0035] The scanning data mainly includes the position information of the infrared receiving tube connected to the receiving board and the infrared transmitting tube connected to the transmitting board, as well as the corresponding scanning logic.

[0036] After the scanning starts, the infrared receiving tube of the receiving board receives the infrared light signal, converts the infrared light signal into an analog signal, loads it onto the analog signal bus and aggregates it to the main board. The signal conditioning circuit of the main board 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, calculates the coordinate position of the touched object, or uploads it to the host computer, etc.

[0037] In one embodiment, Figure 4 As shown, Figure 4 1 is a structural block diagram of an infrared touch frame of another embodiment, in which only the circuit part related to the embodiment is shown. In the infrared touch frame, a digital signal bus, an analog signal bus and a synchronization signal bus are included between the main board and multiple slave boards; wherein the synchronization signal bus is connected between the signal attenuation circuit of the main board and the signal restoration circuit of the slave board, and is used for the main board to transmit the synchronization signal for triggering infrared scanning to the slave board.

[0038] In this embodiment, the main board transmits the synchronization signal for controlling the infrared lamp to perform scanning to the slave board through the synchronization signal bus, so as to trigger the slave board to scan the infrared lamp.

[0039] like Figure 5 As shown, Figure 5 It is a circuit structure diagram of a host board and a slave board of another embodiment, and only the circuit part related to the embodiment is shown in the figure. Specifically, the host board controls the infrared lamp tube of the receiving board to perform scanning through a synchronization signal. After the main MCU sends the scanning data to the slave MCUs of each slave board for storage, each slave MCU waits for the synchronization signal sent by the main MCU. When the slave MCU of the transmitting board receives the synchronization signal, the synchronization signal is analyzed, and the infrared transmitting tube is controlled to emit an infrared light signal according to the scanning data according to the synchronization signal. When the slave MCU of the receiving board receives the synchronization signal, the synchronization signal is analyzed, and the infrared receiving tube is controlled to scan according to the scanning data according to the synchronization signal. When sending the synchronization signal, the synchronization signal is first attenuated by a signal attenuation circuit, and then restored by a signal restoration circuit.

[0040] In one embodiment, the synchronization signal used by the main board 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 solution of the above embodiment, all slave boards can be driven to perform synchronous scanning through one PWM synchronization signal, thus avoiding complex control logic.

[0042] An embodiment of the infrared touch screen is described below.

[0043] 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 used to attenuate the strong digital signal into a weak analog signal for transmission, thereby reducing the intersection of the strong digital signal and the weak analog signal on the transmission line, thereby reducing the interference of the strong digital signal on the weak analog signal. Each slave board transmits the analog signal back to the main board for centralized touch positioning processing, which simplifies the processing flow of the infrared light signal on the slave board, reduces the complexity of the processing of the analog signal by each slave board, has a fast response speed, improves the frame rate of infrared scanning, and improves the performance of the infrared touch frame.

[0044] 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.

[0045] 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, comprising a main board and a plurality of slave boards, wherein the main board and the slave boards are cascade-connected via connecting wires; characterized in that: The host board is connected to the slave board via a digital signal bus, and the host board is connected to the slave board via an analog signal bus; The host board is provided with a signal attenuation circuit, and the slave board is provided with a signal restoration circuit; The signal attenuation circuit and the signal restoration circuit are connected via a digital signal bus; The main board outputs a strong digital signal to the signal attenuation circuit for attenuation, and transmits it to the signal restoration circuit on the slave board through the digital signal bus to restore it to a strong digital signal for use; The slave board transmits the weak analog signal back to the host board through the analog signal bus for centralized processing.

2. The infrared touch frame according to claim 1, characterized in that: The strong digital signal is a control signal used by the main board to control the infrared lamp of the slave board to scan, and the weak analog signal is an analog electrical signal converted from the infrared light signal collected by the slave board.

3. The infrared touch frame according to claim 1, characterized in that: The main board is also provided with a signal conditioning circuit, an A / D sampling circuit and a main MCU which are 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.

4. The infrared touch frame according to claim 3, characterized in that: 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.

5. The infrared touch frame according to claim 1, characterized in that: The signal attenuation circuit includes a passive attenuation circuit or an active attenuation circuit; the signal restoration circuit includes a common-phase amplifier circuit, an inverting amplifier circuit, a triode amplifier circuit or a comparator circuit.

6. The infrared touch frame according to claim 1, characterized in that: The slave board includes a receiving board and a transmitting board; wherein the master board is connected to each receiving board and transmitting board via a digital signal bus, and the master board is connected to each receiving board via an analog signal bus.

7. The infrared touch frame according to any one of claims 1 to 6, characterized in that: The signal bus also includes a synchronous signal bus connected between the signal attenuation circuit of the main board and the signal restoration circuit of the slave board, and is used for the main board to transmit a synchronous signal for triggering infrared scanning to the slave board.

8. The infrared touch frame according to claim 7, characterized in that: The main board transmits the synchronization signal for controlling the infrared lamp to perform scanning to the slave board through the synchronization signal bus, so as to trigger the slave board to scan the infrared lamp.

9. The infrared touch frame according to claim 8, 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.

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

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