An electrically powered shield for shielding voice acquisition of a laser microphone

Abstract

This utility model discloses an electric protective curtain for shielding voice acquisition by a laser microphone, comprising a protective curtain, a roller, a roller motor, a housing, and a controller. The two ends of the roller are rotatably connected to the housing, the upper end of the protective curtain is connected to the roller, and the lower end hangs down naturally. The roller motor drives the roller to rotate, and the controller controls the rotation of the roller motor. The controller includes a random signal generator and a driver chip. The electric protective curtain provided by this utility model uses random, minute vibrations of the protective curtain to interfere with the laser reflected on the curtain, causing the random vibration signal of the protective curtain to mask the vibration signal caused by voice, preventing the laser microphone from deciphering voice information from the returned laser, thus achieving the technical effect of shielding the laser microphone and protecting indoor voice information security.

Description

Technical Field

[0001] This utility model relates to an electric protective screen for shielding voice acquisition by laser microphones, belonging to the field of communication interference technology. Background Technology

[0002] A laser microphone is a device that transmits and receives laser signals over a long distance to detect faint vibrations of objects near the speaker, then demodulates and reconstructs the sound to capture it. By shining a laser beam through a window into a room, the indoor sound can be reconstructed, achieving the effect of acquisition and recording. Therefore, preventing or hindering a laser microphone from acquiring speech is called shielding.

[0003] Chinese utility model patent ZL 202323489399.8 discloses an anti-laser eavesdropping interference device. This technical solution includes a vibrating ball and a device body. The vibrating ball has a first cavity inside, within which a vibrating motor is installed. The device body has a second cavity inside, within which at least one vibrating ball is installed. The device body has suction cups on its exterior for attaching it to glass. This device transmits the irregular vibrations of the vibrating ball to the glass, achieving an anti-eavesdropping effect through the application of irregular interference signals.

[0004] Additionally, Chinese invention patent number ZL 201911312150.5 discloses a sunshade with anti-eavesdropping function. This sunshade includes a window with an internal window opening. A transmission cavity is located on the right side of the window, containing a transmission mechanism that provides power to a device. An anti-eavesdropping mechanism with anti-eavesdropping function is located inside the window, including a first driven cavity located above the transmission cavity. During operation, noise isolation layers are provided at the inner and outer ends of the soundproof panel to disrupt sound information that can pass through, achieving a double-layer anti-eavesdropping effect.

[0005] Similarly, existing technologies for shielding laser microphone voice information acquisition include: ① attaching anti-laser film to window glass. This solution is only effective for specific wavelength bands and low-power laser signals, and there is some light transmittance, so a small amount of laser signal, about 1%, can still enter the room; ② adding conventional shielding curtains. This solution is ineffective for laser microphones with high vibration sensitivity, as these microphones can still acquire indoor voice by picking up vibrations from the shielding curtain; ③ applying vibration maskers to windows or building structures. This solution is cumbersome and complex to install, and the noise problem affects normal work and life, limiting its practical application scenarios and resulting in poor effectiveness. Utility Model Content

[0006] The technical problem to be solved by this utility model is to provide an electric protective screen for shielding the voice acquisition of laser microphones.

[0007] To achieve the above technical objectives, the present invention adopts the following technical solution: According to an embodiment of the present invention, an electrically operated protective screen for shielding voice acquisition from a laser microphone is provided, comprising a protective screen, a roller, a roller motor, a housing, and a controller; wherein... Both ends of the roller are rotatably connected to the housing; the upper end of the protective curtain is connected to the roller, and the lower end hangs down naturally; the roller motor is connected to the roller and can drive the roller to rotate; the controller is connected to the roller motor and can control the rotation of the roller motor. The controller includes a random signal generator and a driver chip.

[0008] Preferably, the power supply is connected to the VCC terminal of the random signal generator and the VDD terminal of the driver chip; the first output terminal of the random signal generator is connected to the first input terminal of the driver chip, and the second output terminal of the random signal generator is connected to the second input terminal of the driver chip; the first output terminal of the driver chip is connected to one pole of the roller shutter motor, and the other pole of the roller shutter motor is connected to the second output terminal of the driver chip.

[0009] Preferably, a capacitor is connected in parallel between the first output terminal and the second output terminal of the driver chip.

[0010] Preferably, the protective screen is a screen that can prevent or hinder the laser microphone from acquiring voice.

[0011] Preferably, the random signal generator is used to generate unpredictable random level signals, or to generate approximately random sequences through a linear feedback shift register.

[0012] Preferably, the driver chip is used to amplify the weak control signal and convert it into a high-power output to directly drive the load.

[0013] Preferably, the driver chip adopts an H-bridge architecture, which supports bidirectional driving.

[0014] The electric protective curtain provided by this utility model is installed in the same way as a regular electric curtain, requiring no modification or reconstruction of the house. It also features low noise and allows windows to be opened. Installing this electric protective curtain on windows in rooms where there is a risk of laser microphones intercepting voice information can protect the security of indoor voice information. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of an electric protective curtain for shielding voice acquisition from a laser microphone, as described in an embodiment of the present invention. Figure 2 for Figure 1 The circuit diagram of the controller in the diagram; Figure 3 for Figure 1 Vibration curve when the protective curtain in the middle is activated and its shielding function is turned on; Figure 4 A schematic diagram of the voice signal acquired by the laser microphone in an embodiment without the present invention applied; Figure 5 This is a schematic diagram of the voice signal acquired by the laser microphone after applying the embodiments of the present invention. Detailed Implementation

[0016] The technical content of this utility model will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0017] The technical concept in this embodiment of the invention is to cause the added shielding curtain to vibrate irregularly, thereby interfering with the signal received by the laser microphone. Specifically, the shielding curtain is raised and lowered by a roller shutter motor to cover the window. When the shielding function is activated, the shielding curtain generates random micro-vibrations with irregular periods and frequencies through the roller shutter motor, interfering with the vibration pickup of the laser microphone and achieving the technical effect of shielding the microphone from acquiring voice information.

[0018] like Figure 1 As shown, this embodiment of the present invention provides an electrically operated protective screen for shielding voice acquisition by a laser microphone, comprising a protective screen 1, a roller 2, a roller motor 3, a housing 4, and a controller 5. The protective screen 1 is a screen capable of blocking or hindering voice acquisition by a laser microphone. The roller 2 is a hollow tube structure with a longitudinal direction. The roller motor 3 is an electric motor. The housing 4 is a frame support structure.

[0019] The housing 4 is supported above the window 100, and both ends of the roller 2 are rotatably connected to the housing 4. The upper end of the protective curtain 1 is connected to the roller 2, and the lower end hangs down naturally. The roller shutter motor 3 is connected to the roller 2 and can drive the roller 2 to rotate, thereby causing the protective curtain 1 to wrap around the roller 2, raising the lower end of the protective curtain 1, or vice versa. The controller 5 connects the roller shutter motor 3 and the power supply 200, providing power to the roller shutter motor 3 and controlling the direction, speed, and rotation stroke of the roller shutter motor 3.

[0020] Preferably, the electrically operated protective curtain for shielding laser microphone voice acquisition provided in this embodiment of the present invention further includes a position sensor 6. The position sensor 6 is connected and fixed to the housing 4 or a wall, and is arranged along the vertical direction of the protective curtain 1. It can detect the position of the lower end of the protective curtain 1, or detect whether the lower end of the protective curtain 1 is within the designed position range. The position sensor 6 is electrically connected to the controller 5 and can provide the controller 5 with a position signal of the lower end of the protective curtain 1. The controller 5 can control the rotation of the roller shutter motor 3 according to the control signal from the position sensor 6, thereby changing the coverage area of ​​the protective curtain 1.

[0021] like Figure 2 As shown, the controller 5 includes a random signal generator 51 and a driver chip 52. In one embodiment of this invention, the random signal generator 51 is implemented using a ZW20U6x, and the driver chip 52 is implemented using an HXA2810. A power supply 200 is connected to the VCC terminal of the random signal generator 51 and the VDD terminal of the driver chip 52 to provide power to the electric protective curtain. The first output terminal of the random signal generator 51 is connected to the first input terminal of the driver chip 52, and the second output terminal of the random signal generator 51 is connected to the second input terminal of the driver chip 52. The first output terminal of the driver chip 52 is connected to one pole of the roller shutter motor 3, and the other pole of the roller shutter motor 3 is connected to the second output terminal of the driver chip 52.

[0022] Preferably, a capacitor Cout is connected in parallel between the first output terminal and the second output terminal of the driver chip 52 to suppress high-frequency noise from the motor.

[0023] It is worth noting that the random signal generator 51 is used to generate unpredictable random level signals (high / low levels), or to generate approximately random sequences through a linear feedback shift register, the frequency bandwidth of which depends on design requirements. The driver chip 52 can amplify weak control signals (such as the output of the random signal generator 51) and convert them into high-power outputs to directly drive the load (in this embodiment, the roller shutter motor 3). Preferably, the driver chip 52 adopts an H-bridge architecture, supporting bidirectional driving.

[0024] Power supply 200 supplies power to random signal generator 51 and driver chip 52. Random signal generator 51 generates random high / low level signals, which are input to IN1 and IN2 of driver chip 52, respectively. Driver chip 52 controls the start / stop, forward and reverse rotation states of roller shutter motor 3 through the logic level combination of IN1 and IN2. Due to the random changes in the input signal, roller shutter motor 3 will switch irregularly between forward rotation, reverse rotation and stop, realizing "random operation".

[0025] The roller blind motor 3 drives the roller shaft 2 to rotate in the designed direction, releasing the protective curtain 1 so that it covers the window 100, thus blocking the laser from the laser microphone from shining into the room. Therefore, when the laser shines on the protective curtain 1, the laser microphone attempts to extract voice information by picking up the vibrations caused by indoor speech. When the shielding function is activated, the protective curtain 1 moves up and down and shakes randomly under the random operation of the roller blind motor 3 (e.g., ...). Figure 3 As shown), random vibrations are generated, which can create "noise" signals that mask speech information. Figure 4 and Figure 5As shown, the randomly vibrating protective curtain 1 blocks the transmission of laser microphone signals into the room and generates random micro-vibrations with irregular periods and frequencies, interfering with the laser microphone and playing a shielding and protective role.

[0026] Because of the covering characteristics of this invention, even if the window is not covered with glass, it can still block the laser microphone. Therefore, this invention is also applicable to covering entrances, tunnels, or ventilation ducts and other building openings with clear boundaries to block the laser microphone from obtaining sound from inside the building, without affecting ventilation.

[0027] In summary, this utility model provides an electric protective curtain for shielding voice acquisition by laser microphones. A random signal generator generates random level signals, which are input to the IN1 / IN2 pins of a driver chip. This controls the roller blind motor to randomly rotate forward, reverse, or stop, resulting in disordered movement and random micro-vibrations of the protective curtain. These random micro-vibrations interfere with the laser reflected from the curtain, masking the vibration signals caused by voice. This prevents the laser microphone from extracting voice information from the returned laser, achieving the technical effect of shielding the laser microphone and protecting indoor voice information security. To shield indoor voice interception by laser microphones, this solution is designed to cover the entire wavelength band, is easy to install and operate, and does not interfere with normal indoor work and life. Its installation method is equivalent to that of ordinary electric curtains (roller blinds), making implementation quick and convenient without additional construction.

[0028] It should be noted that the above embodiments are merely illustrative examples. The technical solutions of the various embodiments can be combined, and all are within the protection scope of this utility model.

[0029] The terms “up,” “down,” “horizontal,” “vertical,” etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0030] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0031] The above provides a detailed description of an electrically operated protective screen for shielding voice acquisition from a laser microphone, as provided by this utility model. Any obvious modifications made to this utility model by those skilled in the art without departing from its essential content will constitute an infringement of the patent rights of this utility model and will incur corresponding legal liability.

Claims

1. An electrically powered protective screen for shielding a laser microphone from voice acquisition, characterized in that Includes protective curtain, roller, roller shutter motor, housing, and controller; among which, Both ends of the roller are rotatably connected to the housing; the upper end of the protective curtain is connected to the roller, and the lower end hangs down naturally; the roller motor is connected to the roller and is used to drive the roller to rotate; the controller is connected to the roller motor and is used to control the rotation of the roller motor. The controller includes a random signal generator and a driver chip.

2. The electrically operated protective curtain as described in claim 1, characterized in that: The first output terminal of the random signal generator is connected to the first input terminal of the driver chip, and the second output terminal of the random signal generator is connected to the second input terminal of the driver chip; the first output terminal of the driver chip is connected to one pole of the roller shutter motor, and the other pole of the roller shutter motor is connected to the second output terminal of the driver chip.

3. The electrically operated protective curtain as described in claim 2, characterized in that: A capacitor is connected in parallel between the first output terminal and the second output terminal of the driver chip.

4. The electrically operated protective curtain as described in claim 1, characterized in that: The protective screen is a screen that can block or hinder the laser microphone from acquiring voice.

5. The electrically operated protective curtain as described in claim 3, characterized in that: The random signal generator is used to generate unpredictable random level signals, or to generate approximately random sequences through a linear feedback shift register.

6. The electrically operated protective curtain as described in claim 3, characterized in that: The driver chip is used to amplify weak control signals and convert them into high-power output to directly drive the load.

7. The electrically operated protective curtain as described in claim 6, characterized in that: The driver chip adopts an H-bridge architecture and supports bidirectional driving.

8. The electrically operated protective curtain as described in claim 1, characterized in that: The random signal generator is implemented using ZW20U6x, and the driver chip is implemented using HXA2810.

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