Infrared signal processing device, infrared touch screen and touch equipment

Abstract

The utility model provides an infrared signal processing device, an infrared touch screen and touch equipment. The infrared signal processing device comprises an infrared receiving module, a pre-amplification module, a filtering module, a post-amplification module and a control module, the output end of the infrared receiving module is connected with the input end of the pre-amplification module, the output end of the pre-amplification module is connected with the input end of the filtering module, the output end of the filtering module is connected with the input end of the post-amplification module, and the output end of the post-amplification module is connected with the input end of the control module. The control end of the control module is connected with the controlled end of the filtering module; the filtering module comprises a plurality of band-stop filters with different stop-band ranges. According to the utility model, the plurality of band elimination filters with different stop band ranges are arranged, so that when the infrared signals of the touch screen are influenced by interference signals, the control module can be utilized to select the band elimination filter corresponding to the interference frequency to filter the interference signals, and the touch signal data acquired by the control module are ensured to be normal.

Description

Technical Field

[0001] The utility model relates to the technical field of touch screens, in particular to an infrared signal processing device, an infrared touch screen and a touch device. Background Art

[0002] At present, due to its strong operation convenience, the infrared touch screen has been widely used in various scenarios. The infrared touch screen forms a horizontal and vertical cross infrared ray matrix by using infrared transmitting tubes and infrared receiving tubes arranged on the four sides of the screen. When a user touches the screen, the infrared rays at the touched position will be blocked, so that the position of the touch point on the screen can be judged. In the existing infrared signal processing circuit, a filter with a relatively wide filtering bandwidth range is usually adopted. However, when at least two infrared touch screens are placed side by side, the infrared receiving tubes in the infrared touch screen are likely to receive the infrared rays emitted by the infrared transmitting tubes in another infrared touch screen placed side by side. Due to the poor filtering effect of the filter with a relatively wide filtering bandwidth range, the infrared signal of itself is easily superimposed with the interference signal, resulting in the attenuation or cancellation of the effective signal, and further causing the touch signal data collected by the control module in the infrared touch screen to be abnormal, so that the infrared touch screen cannot be used normally. Summary of the Utility Model

[0003] The utility model provides an infrared signal processing device, an infrared touch screen and a touch device. By setting a plurality of band-stop filters with different stopband ranges, when the infrared signal of itself is affected by the interference signal, the control module can be used to select the band-stop filter corresponding to the interference frequency to filter out the interference signal, ensure that the touch signal data collected by the control module is normal, and ensure the normal use of the infrared touch screen.

[0004] In order to solve the above technical problems, in the first aspect of the embodiment of the utility model, an infrared signal processing device is provided, which includes an infrared receiving module, a preamplification module, a filtering module, a postamplification module and a control module;

[0005] The output end of the infrared receiving module is connected to the input end of the preamplification module, the output end of the preamplification module is connected to the input end of the filtering module, the output end of the filtering module is connected to the input end of the postamplification module, the output end of the postamplification module is connected to the input end of the control module, and the control end of the control module is connected to the controlled end of the filtering module; the filtering module includes a plurality of band-stop filters with different stopband ranges.

[0006] As a preferred solution, the filtering module further includes a first single-pole multi-throw switch and a second single-pole multi-throw switch;

[0007] The knife end of the first single-pole multi-throw switch is connected to the output end of the preamplification module. Each throw end of the first single-pole multi-throw switch is respectively connected to the input end of any one of the band-stop filters. Each throw end of the second single-pole multi-throw switch is respectively connected to the output end of any one of the band-stop filters. The knife end of the second single-pole multi-throw switch is connected to the input end of the post-amplification module. The control ends of the control module are respectively connected to the controlled ends of the first single-pole multi-throw switch and the second single-pole multi-throw switch.

[0008] As a preferred solution, the band-stop filter includes a low-pass filter circuit, a high-pass filter circuit, and a non-inverting summing circuit;

[0009] The input ends of the low-pass filter circuit and the high-pass filter circuit are both used to access the signal output by the preamplification module. The output ends of the low-pass filter circuit and the high-pass filter circuit are both connected to the input end of the non-inverting summing circuit. The output end of the non-inverting summing circuit is used to output the filtered signal to the post-amplification module.

[0010] As a preferred solution, the low-pass filter circuit includes a first resistor, a second resistor, and a first capacitor;

[0011] One end of the first resistor is used to access the signal output by the preamplification module. The other end of the first resistor is connected to one end of the second resistor. The other end of the second resistor is connected to the input end of the non-inverting summing circuit. One end of the first capacitor is connected between the first resistor and the second resistor. The other end of the first capacitor is grounded.

[0012] As a preferred solution, the high-pass filter circuit includes a second capacitor, a third capacitor, and a third resistor;

[0013] One end of the second capacitor is used to access the signal output by the preamplification module. The other end of the second capacitor is connected to one end of the third capacitor. The other end of the third capacitor is connected to the input end of the non-inverting summing circuit. One end of the third resistor is connected between the second capacitor and the third capacitor. The other end of the third resistor is connected to the output end of the non-inverting summing circuit.

[0014] As a preferred solution, the non-inverting summing circuit includes an operational amplifier, a fourth resistor, and a fifth resistor;

[0015] The non-inverting input terminal of the operational amplifier is respectively connected to the input terminal of the low-pass filter circuit and the input terminal of the high-pass filter circuit. The inverting input terminal of the operational amplifier is connected to one end of the fourth resistor, and the other end of the fourth resistor is grounded. The output terminal of the operational amplifier is used to output the filtered signal to the post-amplification module. One end of the fifth resistor is connected to the output terminal of the operational amplifier, and the other end of the fifth resistor is connected to the inverting input terminal of the operational amplifier.

[0016] In a second aspect of the embodiments of the present invention, an infrared touch screen is provided, which includes the infrared signal processing device according to any one of the first aspects.

[0017] In a third aspect of the embodiments of the present invention, a touch device is provided, which includes the infrared touch screen according to the second aspect.

[0018] Compared with the prior art, the beneficial effects of the embodiments of the present invention are that by setting a plurality of band-stop filters with different stopband ranges, when the self-infrared signal is affected by an interference signal, the control module can be used to select a band-stop filter corresponding to the interference frequency to filter out the interference signal, ensuring the normal touch signal data collected by the control module and guaranteeing the normal use of the infrared touch screen. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a schematic structural diagram of the infrared signal processing device in the embodiments of the present invention;

[0020] Figure 2 is a schematic diagram showing that the effective signal after the superposition of the self-infrared signal and the interference signal in the prior art is cancelled;

[0021] Figure 3 is a schematic diagram showing that the effective signal after the superposition of the self-infrared signal and the interference signal in the prior art is attenuated;

[0022] Figure 4 is a schematic logic diagram of anti-interference processing in the embodiments of the present invention;

[0023] Figure 5 is a schematic structural diagram of the filter module in the embodiments of the present invention;

[0024] Figure 6 is a schematic circuit connection diagram of the band-stop filter in the embodiments of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0025] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. The purpose of providing these embodiments is to make the disclosure of the present utility model more thorough and comprehensive. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the scope of protection of the present utility model.

[0026] In the description of the present application, the terms "first", "second", "third", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first", "second", "third", etc. may explicitly or implicitly include one or more of such features. In the description of the present application, unless otherwise stated, the meaning of "a plurality" is two or more.

[0027] In the description of the present application, it should be noted that unless otherwise clearly defined and limited, the terms "mounted", "connected", "coupled" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements. The terms "vertical", "horizontal", "left", "right", "upper", "lower" and similar expressions used herein are only for the purpose of illustration and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be understood as a limitation to the present utility model. The term "and / or" used herein includes any and all combinations of one or more of the related listed items. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0028] In the description of the present application, it should be noted that unless otherwise defined, all technical and scientific terms used in the present utility model have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present utility model belongs. The terms used in the specification of the present utility model are only for the purpose of describing specific embodiments and are not intended to limit the present utility model. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0029] See Figure 1 , a first aspect of the embodiment of the present utility model provides an infrared signal processing device, including an infrared receiving module 101, a pre-amplification module 102, a filtering module 103, a post-amplification module 104, and a control module 105;

[0030] The output end of the infrared receiving module 101 is connected to the input end of the pre-amplification module 102. The output end of the pre-amplification module 102 is connected to the input end of the filtering module 103. The output end of the filtering module 103 is connected to the input end of the post-amplification module 104. The output end of the post-amplification module 104 is connected to the input end of the control module 105. The control end of the control module 105 is connected to the controlled end of the filtering module 103. The filtering module 103 includes a plurality of band-stop filters with different stopband ranges.

[0031] Specifically, the infrared receiving module 101 in this embodiment is specifically an infrared receiving tube that converts an infrared light signal into an electrical signal. Further, since the intensity of the infrared light signal received by the infrared receiving module 101 is relatively weak, in order to ensure that the subsequent control module 105 can effectively identify and process the infrared signal and ensure that the screen has a high touch control sensitivity, it is necessary to use the pre-amplification module 102 to perform the first amplification process on the infrared signal converted into an electrical signal. Further, as Figure 2 and Figure 3 shown, when there are at least two infrared touchscreens placed side by side in the existing infrared signal processing circuit, the effective signal after the superposition of its own infrared signal and the interference signal will be attenuated or cancelled, resulting in abnormal touch signal data finally collected. Therefore, in this embodiment, the filtering module 103 is set to filter out the interference signal. The filtering module 103 includes a plurality of band-stop filters with different stopband ranges, and it is controlled by the control module 105 to switch the band-stop filter. It can be understood that for different touchscreens, the frequencies of the infrared light signals emitted by their infrared transmitting tubes may be different. Therefore, in this embodiment, the band-stop filters with different stopband ranges are used to filter out the interference signals of each specific frequency. In addition, as Figure 4As shown, in this embodiment, the frequency of the infrared light signal emitted by the infrared emitter is adjustable. When it detects that its own infrared light signal is interfered with, it can change the frequency of the infrared light signal it emits to avoid the frequency of the infrared light signal it emits being the same as or close to that of the interference signal. The reason is that a band-stop filter usually has a preset stopband range. If the frequency of the infrared light signal emitted by itself is the same as or close to that of the interference signal, when filtering the interference signal, it is easy to filter out the infrared light signal emitted by itself at the same time, making the control module 105 unable to recognize the touch signal. After changing the frequency of the infrared light signal it emits, the control module 105 is used to select a band-stop filter whose stopband range corresponds to the frequency of the interference signal to filter out the interference signal during the infrared signal processing. Further, in order to improve the recognition success rate of the infrared signal, this embodiment uses the post-amplification module 104 to perform a second amplification process on the infrared signal and output it to the control module 105. The control module 105 is used to determine the corresponding touch signal according to the received infrared signal to realize the touch function of the infrared touch screen.

[0032] As a preferred solution, the filtering module 103 further includes a first single-pole multi-throw switch K1 and a second single-pole multi-throw switch K2;

[0033] The knife end of the first single-pole multi-throw switch K1 is connected to the output end of the pre-amplification module 102. Each throw end of the first single-pole multi-throw switch K1 is respectively connected to the input end of any one of the band-stop filters. Each throw end of the second single-pole multi-throw switch K2 is respectively connected to the output end of any one of the band-stop filters. The knife end of the second single-pole multi-throw switch K2 is connected to the input end of the post-amplification module 104. The control end of the control module 105 is respectively connected to the controlled end of the first single-pole multi-throw switch K1 and the controlled end of the second single-pole multi-throw switch K2.

[0034] Specifically, as Figure 5 shown, in this embodiment, a single-pole multi-throw switch is used to realize the selection of the band-stop filter. It can be understood that the single-pole multi-throw switch can be a single-pole double-throw switch, a single-pole triple-throw switch, a single-pole quadruple-throw switch, etc., which can be set based on the number of band-stop filters. This embodiment does not make specific limitations here. When it is necessary to filter out an interference signal of a certain frequency, the control module 105 is used to control the knife ends of the first single-pole multi-throw switch K1 and the second single-pole multi-throw switch K2 to be connected to the throw ends connected to the band-stop filter whose stopband range corresponds to the frequency of the interference signal, so as to form a path between the band-stop filter and the infrared receiving module 101, the pre-amplification module 102, the post-amplification module 104 and the control module 105, and filter out the interference signal during the infrared signal processing.

[0035] See Figure 6, As a preferred solution, the band-stop filter includes a low-pass filter circuit, a high-pass filter circuit, and an in-phase summing circuit;

[0036] The input ends of the low-pass filter circuit and the high-pass filter circuit are both used to access the signal output by the pre-amplification module 102. The output ends of the low-pass filter circuit and the high-pass filter circuit are both connected to the input end of the in-phase summing circuit. The output end of the in-phase summing circuit is used to output the filtered signal to the post-amplification module 104.

[0037] Specifically, in this embodiment, the signal output by the pre-amplification module 102 acts on the low-pass filter circuit and the high-pass filter circuit simultaneously, and then the in-phase summing circuit sums the output signals of the low-pass filter circuit and the high-pass filter circuit to achieve the filtering of signals in a specific frequency range. It can be understood that by adjusting the device parameters in the low-pass filter circuit and the high-pass filter circuit, the upper cut-off frequency and the lower cut-off frequency of the band-stop filter can be adjusted, so that several band-stop filters with different stopband ranges can be set.

[0038] , As a preferred solution, the low-pass filter circuit includes a first resistor R1, a second resistor R2, and a first capacitor C1;

[0039] One end of the first resistor R1 is used to access the signal output by the pre-amplification module 102. The other end of the first resistor R1 is connected to one end of the second resistor R2. The other end of the second resistor R2 is connected to the input end of the in-phase summing circuit. One end of the first capacitor C1 is connected between the first resistor R1 and the second resistor R2, and the other end of the first capacitor C1 is grounded.

[0040] , As a preferred solution, the high-pass filter circuit includes a second capacitor C2, a third capacitor C3, and a third resistor R3;

[0041] One end of the second capacitor C2 is used to access the signal output by the pre-amplification module 102. The other end of the second capacitor C2 is connected to one end of the third capacitor C3. The other end of the third capacitor C3 is connected to the input end of the in-phase summing circuit. One end of the third resistor R3 is connected between the second capacitor C2 and the third capacitor C3, and the other end of the third resistor R3 is connected to the output end of the in-phase summing circuit.

[0042] , As a preferred solution, the in-phase summing circuit includes an operational amplifier U1, a fourth resistor R4, and a fifth resistor R5;

[0043] The non-inverting input terminal of the operational amplifier U1 is respectively connected to the input terminal of the low-pass filter circuit and the input terminal of the high-pass filter circuit. The inverting input terminal of the operational amplifier U1 is connected to one end of the fourth resistor R4, and the other end of the fourth resistor R4 is grounded. The output terminal of the operational amplifier U1 is used to output the filtered signal to the post-amplification module 104. One end of the fifth resistor R5 is connected to the output terminal of the operational amplifier U1, and the other end of the fifth resistor R5 is connected to the inverting input terminal of the operational amplifier U1.

[0044] It should be noted that in this embodiment, by adjusting the resistance values of the first resistor R1 and the second resistor R2 and the capacitance value of the first capacitor C1, the cut-off frequency of the low-pass filter circuit can be adjusted; by adjusting the capacitance values of the second capacitor C2 and the third capacitor C3 and the resistance value of the third resistor R3, the cut-off frequency of the high-pass filter circuit can be adjusted. Based on this, the adjustment of the upper cut-off frequency and the lower cut-off frequency of the band-stop filter can be realized.

[0045] The infrared signal processing device provided by the embodiment of the present invention, by setting a plurality of band-stop filters with different stopband ranges, when its own infrared signal is affected by interference signals, can use the control module 105 to select a band-stop filter corresponding to the interference frequency to filter out the interference signals, ensuring the normal touch signal data collected by the control module 105 and guaranteeing the normal use of the infrared touch screen.

[0046] The second aspect of the embodiment of the present invention provides an infrared touch screen, including the infrared signal processing device according to any one of the first aspect embodiments.

[0047] The third aspect of the embodiment of the present invention provides a touch device, including the infrared touch screen according to the second aspect.

[0048] The infrared signal processing device, infrared touch screen and touch device provided by the embodiment of the present invention, by setting a plurality of band-stop filters with different stopband ranges, when its own infrared signal is affected by interference signals, can use the control module to select a band-stop filter corresponding to the interference frequency to filter out the interference signals, ensuring the normal touch signal data collected by the control module and guaranteeing the normal use of the infrared touch screen.

[0049] The above is the preferred embodiment of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements are also regarded as the protection scope of the present invention.

Claims

1. An infrared signal processing device, characterized in that, It includes an infrared receiving module, a pre-amplification module, a filtering module, a post-amplification module and a control module; The output end of the infrared receiving module is connected to the input end of the pre-amplification module, the output end of the pre-amplification module is connected to the input end of the filtering module, the output end of the filtering module is connected to the input end of the post-amplification module, the output end of the post-amplification module is connected to the input end of the control module, and the control end of the control module is connected to the controlled end of the filtering module; The filtering module includes a plurality of band-stop filters with different stopband ranges.

2. The infrared signal processing device according to claim 1, wherein The filtering module further includes a first single-pole multi-throw switch and a second single-pole multi-throw switch; The blade end of the first single-pole multi-throw switch is connected to the output end of the pre-amplification module, each throw end of the first single-pole multi-throw switch is respectively connected to the input end of any one of the band-stop filters, each throw end of the second single-pole multi-throw switch is respectively connected to the output end of any one of the band-stop filters, the blade end of the second single-pole multi-throw switch is connected to the input end of the post-amplification module, and the control end of the control module is respectively connected to the controlled end of the first single-pole multi-throw switch and the controlled end of the second single-pole multi-throw switch.

3. The infrared signal processing device according to claim 1, wherein, The band-stop filter includes a low-pass filter circuit, a high-pass filter circuit and an in-phase summing circuit; The input ends of the low-pass filter circuit and the high-pass filter circuit are both used to access the signal output by the pre-amplification module, the output ends of the low-pass filter circuit and the high-pass filter circuit are both connected to the input end of the in-phase summing circuit, and the output end of the in-phase summing circuit is used to output the filtered signal to the post-amplification module.

4. The infrared signal processing device according to claim 3, characterized in that, The low-pass filter circuit includes a first resistor, a second resistor and a first capacitor; One end of the first resistor is used to access the signal output by the pre-amplification module, the other end of the first resistor is connected to one end of the second resistor, the other end of the second resistor is connected to the input end of the in-phase summing circuit, one end of the first capacitor is connected between the first resistor and the second resistor, and the other end of the first capacitor is grounded.

5. The infrared signal processing device according to claim 3, characterized in that, The high-pass filter circuit includes a second capacitor, a third capacitor and a third resistor; One end of the second capacitor is used to access the signal output by the pre-amplification module, the other end of the second capacitor is connected to one end of the third capacitor, the other end of the third capacitor is connected to the input end of the in-phase summing circuit, one end of the third resistor is connected between the second capacitor and the third capacitor, and the other end of the third resistor is connected to the output end of the in-phase summing circuit.

6. The infrared signal processing device according to claim 3, wherein The in-phase summing circuit includes an operational amplifier, a fourth resistor and a fifth resistor; The non-inverting input terminal of the operational amplifier is respectively connected to the input terminal of the low-pass filter circuit and the input terminal of the high-pass filter circuit. The inverting input terminal of the operational amplifier is connected to one end of the fourth resistor, and the other end of the fourth resistor is grounded. The output terminal of the operational amplifier is used to output the filtered signal to the post-amplification module. One end of the fifth resistor is connected to the output terminal of the operational amplifier, and the other end of the fifth resistor is connected to the inverting input terminal of the operational amplifier.

7. An infrared touch screen, characterized in that, An infrared signal processing device according to any one of claims 1 to 6.

8. A touch device, characterized in that, An infrared touch screen according to claim 7.

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