Audio processing system, audio processing method, and smart glasses

Abstract

The technical scheme provides an audio processing system, an audio processing method and smart glasses, and belongs to the technical field of acoustics.A first audio processing circuit performs frequency division processing on an audio input signal according to a frequency division point to obtain a low-frequency signal.An air conduction transducer generates a sound wave according to the low-frequency signal and transmits the sound wave to a user through air.A second audio processing circuit performs frequency division processing on the audio input signal according to the frequency division point to obtain a high-frequency signal.A bone conduction transducer generates mechanical vibration according to the high-frequency signal and transmits the mechanical vibration to the user through human bones.The technical scheme is based on the frequency division point, the first audio processing circuit and the second audio processing circuit perform frequency division processing on the audio input signal respectively, the air conduction transducer and the bone conduction transducer are adapted, the sound leakage prevention effect of the full frequency band can be realized while the sound quality of the full frequency band is ensured, and the sound leakage problem of the traditional open sound generation structure can be solved.

Description

Technical Field

[0001] This technical solution belongs to the field of acoustic technology, and in particular relates to an audio processing system, an audio processing method, and smart glasses. Background Technology

[0002] With the rapid development of artificial intelligence technology and smart wearable terminals, wearable devices, represented by smart glasses, have gradually become important carriers for near-eye display, environmental perception, intelligent monitoring and human-computer interaction, and are widely used in consumer electronics, intelligent assistance, real-scene perception, mobile terminal interaction and other fields.

[0003] As an emerging wearable device, smart glasses typically integrate audio playback functionality into the temples, providing audio output to users through an open-back sound-emitting structure. This offers advantages such as comfortable wear and the ability to perceive ambient sound. However, the open-back sound-emitting structure of traditional smart glasses suffers from sound leakage, allowing audio content to be heard by those nearby, potentially disturbing others and compromising user privacy. Summary of the Invention

[0004] The purpose of this technical solution is to provide an audio processing system, an audio processing method, and smart glasses, aiming to solve the sound leakage problem existing in traditional open sound generation structures.

[0005] This technical solution provides an audio processing system, including: The first audio processing circuit is used to perform frequency division processing on the audio input signal according to the frequency division point to obtain a low-frequency signal; At least one air-conducting transducer, connected to the first audio processing circuit, is used to generate sound waves based on the low-frequency signal and transmit them to the user via the air; The second audio processing circuit is used to perform frequency division processing on the audio input signal according to the frequency division point to obtain a high-frequency signal; At least one bone conduction transducer, connected to the second audio processing circuit, is used to generate mechanical vibrations based on the high-frequency signal and transmit them to the user via the human skeleton.

[0006] This technical solution provides an audio processing method, including: Obtain audio input signal; The first audio processing circuit performs frequency division processing on the audio input signal according to the frequency division point to obtain a low-frequency signal, and then transmits the low-frequency signal to the air conduction transducer. The air-conducting transducer generates sound waves based on the low-frequency signal and transmits them to the user through the air. The second audio processing circuit performs frequency division processing on the audio input signal according to the frequency division point to obtain a high-frequency signal, and then transmits the high-frequency signal to the bone conduction transducer. The bone conduction transducer generates mechanical vibrations based on the high-frequency signal, which are then transmitted to the user through the human skeleton.

[0007] This technical solution provides a smart glasses, including an audio processing system as described in any of the above-mentioned cases and a glasses body, wherein the audio processing system is disposed on the glasses body.

[0008] This technical solution provides an audio processing chip that integrates the audio processing system described in any of the above situations.

[0009] The advantages of this technical solution compared to existing technologies are: By setting a crossover point, the first audio processing circuit performs frequency division on the audio input signal to obtain a low-frequency signal. This low-frequency signal serves as the driving signal for the air-conducting transducer. The air-conducting transducer then converts the low-frequency signal into diaphragm mechanical vibration, which disturbs the air to generate sound waves. These sound waves radiate outwards via air coupling and are transmitted to the user. The air-conducting transducer exhibits a wider frequency response and lower nonlinear distortion in the low-frequency range, effectively suppressing low-frequency sound leakage and achieving both low-frequency sound reproduction and low-frequency sound leakage prevention.

[0010] By setting a crossover point, the second audio processing circuit performs frequency division on the audio input signal to obtain a high-frequency signal. This high-frequency signal serves as the driving signal for the bone conduction transducer. The bone conduction transducer then converts the high-frequency signal into mechanical vibrations. The vibrating end face conforms to the human skeleton, transmitting the vibrations through the skeleton to the user's inner ear cochlea via solid-state conduction, eliminating the need for airborne sound waves. The bone conduction transducer exhibits superior conduction efficiency and extremely low airborne sound radiation in the high-frequency range, effectively eliminating high-frequency airborne sound radiation and suppressing high-frequency sound leakage, thus achieving both high-frequency sound reproduction and high-frequency sound leakage prevention.

[0011] Furthermore, the second audio processing circuit, based on the frequency division point, performs frequency division processing on the audio input signal to obtain a high-frequency signal, which is then transmitted to the bone conduction transducer. This compensates for the failure of the air conduction transducer in preventing sound leakage in the high-frequency band, thus achieving full-frequency audio playback. Therefore, the audio processing system provided by this technical solution can achieve full-frequency sound leakage prevention while ensuring full-frequency sound quality, solving the sound leakage problem inherent in traditional open-type sound-emitting structures, and also addressing the poor low-frequency sound quality issue in traditional technologies. Attached Figure Description

[0012] To more clearly illustrate the solutions under various conditions in this technical solution, the accompanying drawings used in the description of various conditions or exemplary technologies will be briefly introduced below. Obviously, the accompanying drawings described below are only one case of this technical solution. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0013] Figure 1 This is a schematic diagram of the overall connection structure of an audio processing system under one scenario, as provided in this technical solution.

[0014] Figure 2 This is a schematic diagram showing the specific connection structure of each unit in the first audio processing circuit and the second audio processing circuit under one scenario provided by this technical solution.

[0015] Figure 3 This is a schematic diagram of the sound outlet, sound vent, and air-conducting diaphragm of an air-conducting transducer under one condition, which is provided for this technical solution.

[0016] Figure 4 This is a flowchart illustrating the steps of an audio processing method provided in this technical solution.

[0017] Figure 5 This is a schematic diagram of the structure of smart glasses in one scenario provided by this technical solution.

[0018] Figure 6 This is a schematic diagram comparing the leakage volume at 20cm with the air-conducting acoustic dipole technology and traditional technology solutions. Detailed Implementation

[0019] To make the technical problem to be solved, the technical solution, and the beneficial effects of this technical solution clearer, the following detailed description, in conjunction with the accompanying drawings and various scenarios, further illustrates this technical solution. It should be understood that the specific circumstances described herein are merely for explaining this technical solution and are not intended to limit it.

[0020] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0021] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" 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 technical solution and simplifying the description, and do not indicate or imply that the device or component 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 technical solution.

[0022] 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 technical features indicated. Therefore, a feature marked with "first" or "second" may explicitly or implicitly include one or more of that feature. Additionally, in various scenarios of this technical solution, the terms "first" and "second" are used to distinguish identical or similar items with substantially the same function and effect. Those skilled in the art will understand that the terms "first" and "second" do not limit the quantity or order of execution, and that "first" and "second" do not necessarily imply difference.

[0023] In the description of this technical solution, unless otherwise stated, " / " indicates that the objects before and after it are in an "or" relationship. For example, A / B can represent A or B. "And / or" in this technical solution is merely a description of the relationship between the related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, and B alone, where A and B can be singular or plural. Furthermore, in the description of this technical solution, unless otherwise stated, "multiple" refers to two or more. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, or c can represent: a, b, c, ab, ac, bc, or abc, where a, b, and c can be single or multiple.

[0024] Please see Figure 1 This technical solution provides an audio processing system. The audio processing system includes a first audio processing circuit 10, a second audio processing circuit 20, at least one air conduction transducer 100, and at least one bone conduction transducer 200. The number of air conduction transducers 100 and bone conduction transducers 200 can be set according to the actual application scenario. The first audio processing circuit 10 is used to perform frequency division processing on the audio input signal according to the frequency division point to obtain a low-frequency signal. The air conduction transducer 100 is connected to the first audio processing circuit 10 and is used to generate sound waves based on the low-frequency signal and transmit them to the user through the air.

[0025] The second audio processing circuit 20 is used to perform frequency division processing on the audio input signal according to the frequency division point to obtain a high-frequency signal, and then transmit the high-frequency signal to the bone conduction transducer 200. The bone conduction transducer 200 is connected to the second audio processing circuit 20 and is used to generate mechanical vibration according to the high-frequency signal, and transmit it to the user through the human skeleton.

[0026] By setting a frequency division point, the first audio processing circuit 10 performs frequency division processing on the audio input signal to obtain a low-frequency signal. This low-frequency signal serves as the driving signal for the air-conducting transducer 100. The air-conducting transducer 100 then converts the low-frequency signal into diaphragm mechanical vibration, which disturbs the air to generate sound waves. These sound waves radiate outwards via air coupling and are transmitted to the user. The air-conducting transducer 100 has a wider frequency response and lower nonlinear distortion in the low-frequency range, effectively suppressing low-frequency sound leakage and achieving both low-frequency sound playback and low-frequency sound leakage prevention functions.

[0027] By setting a frequency division point, the second audio processing circuit 20 performs frequency division processing on the audio input signal to obtain a high-frequency signal. This high-frequency signal serves as the driving signal for the bone conduction transducer 200. The bone conduction transducer 200 then converts the high-frequency signal into mechanical vibration. The vibrating end face conforms to the human skeleton, transmitting the vibration to the user's inner ear cochlea via solid conduction, eliminating the need for airborne sound waves. The bone conduction transducer 200 exhibits superior conduction efficiency and extremely low airborne sound radiation in the high-frequency range, effectively eliminating high-frequency airborne sound radiation and suppressing high-frequency sound leakage, thus achieving both high-frequency sound reproduction and high-frequency sound leakage prevention.

[0028] Furthermore, the second audio processing circuit 20 performs frequency division processing on the audio input signal based on the frequency division point to obtain a high-frequency signal, which is then transmitted to the bone conduction transducer 200. This compensates for the failure of the air conduction transducer 100 in preventing sound leakage in the high-frequency band, thus achieving full-frequency audio playback. Therefore, the audio processing system provided by this technical solution can achieve full-frequency sound leakage prevention while ensuring full-frequency sound quality, solving the sound leakage problem inherent in traditional open-type sound-emitting structures, and further addressing the problem of poor low-frequency sound quality in traditional technologies.

[0029] In one scenario, the first audio processing circuit 10 and the second audio processing circuit 20 can be two independent audio processing circuits, or they can be integrated into a single audio processing circuit, depending on the actual application scenario.

[0030] In one case, the air conduction transducer 100 can be any one of a moving coil air conduction transducer, a moving iron air conduction transducer, an electromagnetic air conduction transducer, a pneumatic air conduction transducer, or a piezoelectric air conduction transducer, and can be selected according to the actual application scenario.

[0031] The bone conduction transducer 200 can be any one of a piezoelectric bone conduction transducer, a moving coil bone conduction transducer, or a moving magnet bone conduction transducer, and can be selected according to the actual application scenario.

[0032] Please see Figure 2In one embodiment, the first audio processing circuit 10 includes a low-pass filter unit 110. The low-pass filter unit 110 is used to perform low-pass filtering on the audio input signal according to the frequency division point to obtain a low-frequency component signal.

[0033] The crossover point can be understood as the critical frequency value used to divide an audio input signal into different frequency bands. Based on the crossover point, the low-pass filter unit 110 can perform low-pass filtering on the audio input signal to extract the low-frequency component signal. Consequently, the air-conducting transducer 100 can wide-band carry the low-frequency component signal, achieving high-fidelity output of the low-frequency component signal, reducing transmission distortion, and suppressing low-frequency leakage, thus realizing the functions of low-frequency sound reproduction and low-frequency leakage prevention. By setting the crossover point, a trade-off and optimization can be made between optimizing sound quality and suppressing leakage, allowing the air-conducting transducer 100 to output high-quality, leakage-free sound to the user.

[0034] In one embodiment, the low-pass filter unit 110 includes a digital filter, specifically a Linkwitz-Riley filter or a Butterworth filter. The digital filter has an adjustable cutoff frequency, enabling it to filter the audio input signal, extract low-frequency components, and ensure that these components cover the target low-frequency band.

[0035] In one scenario, the low-pass filter unit 110 can employ a 4th-order Linkwitz-Riley filter. Using a 4th-order Linkwitz-Riley filter for frequency band division ensures that high-frequency and low-frequency signals are phase-synchronized at the crossover point, resulting in flat sound pressure leveling. This improves frequency band isolation while meeting phase difference control requirements.

[0036] In one case, the order of the filter used in the low-pass filter unit 110 can be adjusted according to the actual application scenario.

[0037] In one case, the frequency division point can range from 1000Hz to 4000Hz, specifically 2000Hz.

[0038] In one embodiment, the first audio processing circuit 10 further includes a first equalization compensation unit 120. The first equalization compensation unit 120 is connected to the low-pass filter unit 110 and is used to correct the amplitude of different frequencies in the low-frequency component signal according to the measured frequency response curve and the target frequency response curve to obtain a low-frequency equalization compensation signal.

[0039] The target frequency response curve can be understood as a pre-calibrated design reference curve, specifying the target sound pressure output value at each frequency point across the entire frequency band. The target frequency response curve can be set according to the actual application scenario. Using the target frequency response curve as a reference, when there is a deviation between the measured frequency response curve and the target frequency response curve, amplitude correction is performed on each frequency point of the low-frequency component signal to complete equalization compensation and obtain a low-frequency equalization compensation signal, ensuring the flatness and consistency of the overall frequency response. Alternatively, it can be understood that through the first equalization compensation unit 120, using the target frequency response curve as a reference, different frequencies in the low-frequency component signal are amplified or attenuated to achieve signal amplitude correction. When the measured frequency response curve is lower than the target frequency response curve, the low-frequency component signal is amplified to increase its amplitude, obtaining a low-frequency equalization compensation signal to raise the output sound pressure and approach the preset target frequency response curve. When the measured frequency response curve is higher than the target frequency response curve, the low-frequency component signal is attenuated to reduce its amplitude, thereby obtaining a low-frequency equalization compensation signal to lower the output sound pressure and approach the preset target frequency response curve. Thus, by correcting the amplitude of different frequencies in the low-frequency component signal through the first equalization compensation unit 120, the frequency response fluctuations in the low-frequency band of the air-conducting transducer 100 can be compensated.

[0040] In one embodiment, the first audio processing circuit 10 further includes a first phase alignment unit 130. The first phase alignment unit 130 is connected to the first equalization compensation unit 120 and is used to perform phase compensation on the low-frequency equalization compensation signal to obtain a low-frequency phase compensation signal so that the low-frequency signal and the high-frequency signal are phase aligned at the crossover point.

[0041] Phase compensation of the low-frequency equalization compensation signal is performed by the first phase alignment unit 130. This adjusts the phase of the low-frequency equalization compensation signal, aligning the phase of the low-frequency signal transmitted to the air conduction transducer 100 with the phase of the high-frequency signal transmitted to the bone conduction transducer 200 at the crossover point. This eliminates phase shift between the two signals and avoids superposition distortion. Furthermore, the low-frequency and high-frequency signals arrive at the air conduction transducer 100 and bone conduction transducer 200 synchronously, achieving synchronous oscillation and synchronous fallback. This eliminates phase shift between the two channels, ensuring consistent timing of signals of the same frequency and seamless connection. Therefore, the sound transmitted by the air conduction transducer 100 and the sound transmitted by the bone conduction transducer 200 are superimposed in phase at the ear.

[0042] In one embodiment, the first audio processing circuit 10 further includes a first amplification unit 140. The first amplification unit 140 is connected to the first phase alignment unit 130 and is used to adjust the gain of the low-frequency phase compensation signal according to the sensitivity and conversion efficiency of the air-conducting transducer 100 to obtain a low-frequency signal. The first amplification unit 140 is also connected to the air-conducting transducer 100 and is used to send a low-frequency signal to the air-conducting transducer 100.

[0043] Because transducers exhibit individual differences in sensitivity and conversion efficiency, the gain of the low-frequency phase compensation signal is adjusted based on the sensitivity and conversion efficiency of the air-conducting transducer 100. This compensates for the inherent acoustic losses of the device, ensuring that the actual sound pressure output from the two transducers matches the target frequency response curve. The gain of the low-frequency phase compensation signal is adjusted via the first amplification unit 140. When the gain is greater than 1, the first amplification unit 140 amplifies the low-frequency phase compensation signal as a whole, increasing its overall amplitude. When the gain is less than 1, the first amplification unit 140 attenuates the low-frequency phase compensation signal as a whole, decreasing its overall amplitude. By adjusting the gain of the low-frequency phase compensation signal through the first amplification unit 140, overall amplitude adjustment can be achieved, resulting in a low-frequency signal that is then transmitted to the air-conducting transducer 100.

[0044] In one embodiment, the second audio processing circuit 20 includes a high-pass filter unit 210. The high-pass filter unit 210 is used to perform high-pass filtering on the audio input signal according to the frequency division point to obtain the high-frequency component signal.

[0045] The high-pass filter unit 210 can perform high-pass filtering on the audio input signal according to the crossover point to extract the high-frequency component signal. Furthermore, the bone conduction transducer 200 can avoid high-frequency attenuation caused by the air medium and achieve high-fidelity output of the high-frequency component signal with better conduction efficiency, reducing transmission distortion and suppressing high-frequency leakage, thus realizing the functions of high-frequency playback and high-frequency leakage prevention.

[0046] In one embodiment, the high-pass filter unit 210 includes a digital filter, specifically a Linkwitz-Riley filter or a Butterworth filter. The digital filter has an adjustable cutoff frequency, enabling it to filter the audio input signal, extract high-frequency components, and ensure that these components cover the target high-frequency band.

[0047] In one scenario, the high-pass filter unit 210 can employ a 4th-order Linkwitz-Riley filter. Using a 4th-order Linkwitz-Riley filter for frequency band division ensures that high-frequency and low-frequency signals are phase-synchronized at the crossover point, resulting in flat sound pressure leveling. This improves frequency band isolation while meeting phase difference control requirements.

[0048] In one case, the order of the filter used by the high-pass filter unit 210 can be adjusted according to the actual application scenario.

[0049] In one embodiment, the second audio processing circuit 20 further includes a second equalization compensation unit 220. The second equalization compensation unit 220 is connected to the high-pass filter unit 210 and is used to correct the amplitude of different frequencies in the high-frequency component signal to obtain a high-frequency equalization compensation signal.

[0050] Amplitude correction is performed on the high-frequency component signal at each frequency point to complete equalization compensation and obtain a high-frequency equalized compensated signal, thereby ensuring the flatness and consistency of the overall frequency response. Alternatively, it can be understood that the second equalization compensation unit 220 performs gain or attenuation on different frequencies in the high-frequency component signal to achieve signal amplitude correction.

[0051] In one embodiment, the second audio processing circuit 20 further includes a second phase alignment unit 230. The second phase alignment unit 230 is connected to the second equalization compensation unit 220 and is used to perform phase compensation on the high-frequency equalization compensation signal to obtain a high-frequency phase compensation signal so that the high-frequency signal and the low-frequency signal are phase aligned at the crossover point.

[0052] Phase compensation of the high-frequency equalization compensation signal is performed by the second phase alignment unit 230. This adjusts the phase of the high-frequency equalization compensation signal, aligning the low-frequency signal transmitted to the air conduction transducer 100 with the high-frequency signal transmitted to the bone conduction transducer 200 at the crossover point. This eliminates phase shift between the two signals and avoids superposition distortion. Furthermore, the low-frequency and high-frequency signals arrive at the air conduction transducer 100 and bone conduction transducer 200 synchronously, achieving synchronous oscillation and synchronous fallback. This eliminates phase shift between the two channels, ensuring consistent timing of signals of the same frequency and seamless connection. Therefore, the sound transmitted by the air conduction transducer 100 and the sound transmitted by the bone conduction transducer 200 are superimposed in phase at the ear.

[0053] In one case, by performing phase alignment compensation on the low-frequency equalization compensation signal and the high-frequency equalization compensation signal, it can be ensured that the phase difference between the two channels at the frequency division point is within the range of -20° to +20°.

[0054] In one embodiment, the second audio processing circuit 20 further includes a second amplification unit 240. The second amplification unit 240 is connected to the second phase alignment unit 230 and is used to adjust the gain of the high-frequency phase compensation signal according to the sensitivity and conversion efficiency of the bone conduction transducer 200 to obtain a high-frequency signal.

[0055] The second amplification unit 240 is connected to the bone conduction transducer 200 and is used to send high-frequency signals to the bone conduction transducer 200.

[0056] Since there are individual differences in the sensitivity and conversion efficiency of the transducers, performing gain adjustment on the high-frequency phase compensation signal according to the sensitivity and conversion efficiency of the bone conduction transducer 200 can compensate for the inherent acoustic loss of the device, so that the actual output sound pressure of the two transducers matches the target frequency response curve. The gain adjustment of the high-frequency phase compensation signal is performed by the second amplification unit 240. When the gain is greater than 1, the second amplification unit 240 amplifies the high-frequency phase compensation signal as a whole, so that the amplitude increases as a whole. When the gain is less than 1, the second amplification unit 240 attenuates the high-frequency phase compensation signal as a whole, so that the amplitude decreases as a whole. Performing gain adjustment on the high-frequency phase compensation signal through the second amplification unit 240 can realize overall amplitude adjustment, obtain a high-frequency signal, and transmit it to the bone conduction transducer 200.

[0057] See Figure 3 , in one case, the frequency dividing point is determined according to the condition that the acoustic dipole corresponding to the air conduction transducer 100 is approximately valid. Figure 3 where the sound outlet 101 and the sound leakage port 102 are respectively in communication with the front and rear of the air conduction diaphragm 103.

[0058] The air conduction transducer 100 is provided with a sound outlet 101 and a sound leakage port 102, which have a spatial distance d therebetween, and the sound wave at the sound leakage port 102 is opposite in polarity to the sound wave at the sound outlet 101 (with a phase difference of approximately 180°). In the low frequency band (below the frequency dividing point), the distance between the sound outlet 101 and the sound leakage port 102 is much smaller than the sound wavelength. The sound waves radiated to the far field by the sound outlet 101 and the sound leakage port 102 are phase-canceled, so that the far-field sound radiation pattern of the air conduction transducer 100 approximates the characteristics of an acoustic dipole. A radiation zero point is formed in the far field in the direction perpendicular to the axis of the acoustic dipole, which significantly reduces the low-frequency sound energy leaking outward. The air conduction transducer 100 can achieve good sound leakage prevention through the acoustic dipole structure design. However, as the sound wave frequency increases to the range of 1000 Hz to 4000 Hz, the acoustic dipole approximation gradually fails, and the sound leakage prevention effect gradually decreases. Therefore, the bone conduction transducer 200 is selected for use in the high frequency band. The selection of the frequency dividing point is exactly based on the valid condition of the acoustic dipole approximation. In one case, a position near the upper limit frequency is selected as the frequency dividing point.

[0059] The valid condition for the acoustic dipole approximation is that the distance d of the air conduction transducer 100 is much smaller than the sound wavelength λ, that is, d<<λ, where λ=c / f (c is the speed of sound, and f is the frequency). Taking the distance d=10 mm as an example, when f<c / (10d)≈3400 Hz (that is, when d is less than 0.1 times the wavelength), the acoustic dipole approximation is valid.

[0060] When the air-conducting transducer 100 emits sound, the positive-phase sound wave and the negative-phase sound wave generated before and after the diaphragm are emitted from the sound outlet 101 and the sound vent 102, respectively, forming an acoustic dipole in a direction perpendicular to the temple and upward. The crossover point is set based on the physical principle that the acoustic dipole is approximately effective in the low-frequency range and ineffective in the high-frequency range, and the range is from 1000 Hz to 4000 Hz. By setting the crossover point, the audio processing system can be flexibly adjusted within the range of 1000 Hz to 4000 Hz to adapt to the temples of different sizes of smart glasses and different transducer specifications.

[0061] In one scenario, the user can dynamically set and adjust the crossover point using the accompanying application software. The user can set the crossover point according to their personal preferences, thereby setting the crossover frequency of the low-pass filter unit 110 and the high-pass filter unit 210. This flexibly divides the operating frequency bands of the air conduction transducer 100 and the bone conduction transducer 200, satisfying different usage scenarios and user listening preferences, and effectively improving the overall experience of audio playback, voice calls, and human-computer interaction.

[0062] In one case, the low-pass filter unit 110, the first equalization compensation unit 120, the first phase alignment unit 130, the first amplification unit 140, the high-pass filter unit 210, the second equalization compensation unit 220, the second phase alignment unit 230, and the second amplification unit 240 in the audio processing system can be integrated into a digital signal processor (DSP) or a microcontroller unit (MCU).

[0063] Please see Figure 4 This technical solution provides an audio processing method, including: Step S10: Obtain the audio input signal; Step S20: The first audio processing circuit 10 performs frequency division processing on the audio input signal according to the frequency division point to obtain a low-frequency signal, and transmits the low-frequency signal to the air conduction transducer 100. In step S30, the air-conducting transducer 100 generates sound waves based on the low-frequency signal and transmits them to the user through the air. In step S40, the second audio processing circuit 20 performs frequency division processing on the audio input signal according to the frequency division point to obtain a high-frequency signal, and transmits the high-frequency signal to the bone conduction transducer 200. In step S50, the bone conduction transducer 200 generates mechanical vibration based on the high-frequency signal and transmits it to the user through the human skeleton.

[0064] The description of step S10 can be found in the description of the audio input signal in the above case. The description of step S20 can be found in the description of the first audio processing circuit 10 in the above case. The description of step S30 can be found in the description of the air conduction transducer 100 in the above case. The description of step S40 can be found in the description of the second audio processing circuit 20 in the above case. The description of step S50 can be found in the description of the bone conduction transducer 200 in the above case.

[0065] In one embodiment, this technical solution provides a wearable audio device, including an audio processing system as described above. Wearable audio devices include eyeglasses, headphones, headsets, smart helmets, and smart bracelets, etc. The wearable audio device provided by this technical solution, based on a frequency division point, performs frequency division processing on the audio input signal through a first audio processing circuit 10 and a second audio processing circuit 20, respectively, and adapts to the air conduction transducer 100 and the bone conduction transducer 200, respectively. This achieves full-frequency sound quality while ensuring full-frequency sound leakage prevention, solving the sound leakage problem inherent in traditional open-type sound-emitting structures.

[0066] Please see Figure 5 This technical solution provides a smart glasses. The smart glasses include an audio processing system and a glasses body 300. The audio processing system is located in the glasses body 300.

[0067] In the audio processing system, the air-conducting transducer 100 is configured to generate sound waves based on a low-frequency signal and transmit them to the user via the air. The low-frequency signal is obtained by the first audio processing circuit 10 in the audio processing system performing frequency division processing on the audio input signal according to the frequency division point.

[0068] In the audio processing system, the bone conduction transducer 200 is configured to generate mechanical vibrations based on high-frequency signals and transmit them to the user via the human skeleton. The high-frequency signals are obtained by the second audio processing circuit 20 in the audio processing system, which performs frequency division processing on the audio input signal according to the frequency division point.

[0069] The number of air conduction transducers 100 and bone conduction transducers 200 can be set according to the actual application scenario. In one case, the smart glasses include one air conduction transducer 100 and one bone conduction transducer 200. In another case, the smart glasses include two air conduction transducers 100 and two bone conduction transducers 200. One air conduction transducer 100 and one bone conduction transducer 200 are arranged as a transducer group on the left temple of the smart glasses. The other air conduction transducer 100 and the other bone conduction transducer 200 are arranged as a transducer group on the right temple of the smart glasses, forming a symmetrical structure with the left temple. For a description of the air conduction transducers 100 and bone conduction transducers 200, please refer to the descriptions of the above-mentioned cases.

[0070] The air conduction transducer 100 and the bone conduction transducer 200 are installed on the main body of the glasses 300, which enables the smart glasses to achieve full-frequency sound quality and full-frequency sound leakage prevention effect. It can realize human-computer interaction capabilities such as multimedia audio playback, Bluetooth voice calls, navigation and message voice broadcast, voice assistant wake-up and voice command control.

[0071] In one configuration, the air conduction transducer 100 and the bone conduction transducer 200 are spaced apart and positioned on the same temple 310 of the glasses body 300. When the user wears the smart glasses, the air conduction transducer 100 is located between the user's temporal region and the auricle 400, and is positioned close to the auricle 400. The bone conduction transducer 200 is positioned away from the auricle 400 and is in contact with the user's skin.

[0072] A pneumatic transducer 100 is disposed on the temple 310. The side wall of the temple 310 has a sound vent 102 and a sound outlet 101 for the pneumatic transducer 100. The main structure of the pneumatic transducer 100 is housed within the casing of the temple 310. A bone conduction transducer 200 is disposed on the temple 310, with its vibrator protruding from the side wall of the temple 310 to rest against the human skull. The main structure of the bone conduction transducer 200 is encapsulated within the casing of the temple 310.

[0073] The air conduction transducer 100 and the bone conduction transducer 200 are spaced apart and disposed within the same temple 310 of the glasses body 300. This can be understood as the air conduction transducer 100 and the bone conduction transducer 200 being arranged along the long axis within the same temple 310 of the glasses body 300. The spaced-apart arrangement of the air conduction transducer 100 and the bone conduction transducer 200 within the same temple 310 makes the structure of the smart glasses compact, does not affect the overall appearance and weight distribution of the smart glasses, and has good mass production feasibility.

[0074] The air conduction transducer 100 is located on the temple 310. When the user wears the smart glasses, the air conduction transducer 100 is located between the user's temporal region and the auricle 400, or in other words, in front of the auricle 400. Figure 5 Region A. The sound outlet 101 of the air-conducting transducer 100 faces the entrance of the external auditory canal. The distance between the sound outlet 102 and the sound outlet 101 is approximately 8mm to 12mm. When the air-conducting transducer 100 emits sound, two sound waves with a phase difference of 180° are generated before and after the air-conducting diaphragm 103, forming an acoustic dipole structure from the sound outlet 101 and the sound outlet 102 respectively.

[0075] The bone conduction transducer 200 is located on the temple 310. When the user wears the smart glasses, the bone conduction transducer 200 is positioned away from the auricle 400, which can be understood as being located behind the auricle 400, or at the end of the temple 310. Figure 5Region B. In one scenario, the bone conduction transducer 200 is located in the mastoid region. When the user wears the smart glasses, the vibrator of the bone conduction transducer 200 contacts the user's skin, and subsequently the mastoid bone. High-frequency sound is transmitted through bone vibration. Thus, through the air conduction transducer 100 and the bone conduction transducer 200, a functional partition is formed in front of and behind the auricle 400, enabling the smart glasses to achieve full-frequency sound quality while preventing sound leakage across the entire frequency range.

[0076] In one configuration, the air conduction transducer 100 and the bone conduction transducer 200 are spaced apart within the same temple 310 of the eyeglass body 300. The temple 310 can be either the left or right temple. One air conduction transducer 100 and one bone conduction transducer 200 are respectively installed on the left and right temples, corresponding to the left and right channels respectively, to achieve stereo output. Both the air conduction transducer 100 and bone conduction transducer 200 on the left and right temples use the same crossover point and the same signal processing procedure, operating independently.

[0077] In one case, when the space of the temple 310 is relatively small, the distance between the sound outlet 102 and the sound outlet 101 of the air conduction transducer 100 is relatively small, and the effective frequency upper limit of the acoustic dipole structure is higher, thus setting the crossover point to 4000Hz, so that the bone conduction transducer 200 can handle a wider high frequency range.

[0078] In one scenario, when there is ample space in the temple 310, the distance between the sound outlet 102 and the sound outlet 101 of the air-conducting transducer 100 is relatively large, reducing the upper limit of the effective frequency of the acoustic dipole structure, thereby lowering the crossover point to 1000Hz to fully utilize the sound quality advantage of the air-conducting transducer 100.

[0079] When the crossover point changes, the cutoff frequencies of the low-pass filter unit 110 and the high-pass filter unit 210 can be adjusted. The first equalization compensation unit 120, the first phase alignment unit 130, the first amplification unit 140, the second equalization compensation unit 220, the second phase alignment unit 230, and the second amplification unit 240 in the audio processing system do not need to be changed.

[0080] Please see Figure 6 A schematic diagram comparing the leakage volume at 20cm between this technical solution, the air-conducting acoustic dipole technology, and traditional technical solutions when the smart glasses produce the same loudness at the human ear. Figure 6As can be seen, when the smart glasses produce the same loudness at the human ear, the sound leakage at 20cm produced by this technical solution is close to that of the air-conducting acoustic dipole technology at low frequencies, and significantly lower than that of the traditional technology. Furthermore, at frequencies above 2000 Hz, the sound leakage produced by this technical solution is significantly lower than that of both the air-conducting acoustic dipole technology and the traditional technology. In the frequency range of 100 Hz to 2000 Hz, the sound leakage produced by this technical solution is reduced by approximately 15.5 dB compared to the traditional technology. The airborne sound radiation of this technical solution at frequencies above 2000 Hz is reduced by approximately 16.4 dB compared to the air-conducting acoustic dipole technology.

[0081] This technical solution provides an audio processing chip that integrates the audio processing system described in any of the above situations.

[0082] It should be understood that the sequence number of each step in the above cases does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not impose any limitations on the implementation process of this technical solution in various cases.

[0083] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and circuits is merely an example. In practical applications, the above functions can be assigned to different functional units and circuits as needed, that is, the internal structure of the device can be divided into different functional units or circuits to complete all or part of the functions described above. Furthermore, the specific names of each functional unit and circuit are only for easy differentiation and are not intended to limit the scope of protection of this technical solution. The specific working process of the units and circuits in the above system can be referred to the corresponding process in the aforementioned cases, and will not be repeated here.

[0084] In the above cases, the descriptions of each situation have their own emphasis. For the parts of a situation that are not described in detail or recorded, please refer to the relevant descriptions in other situations.

[0085] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the circumstances disclosed in this technical solution can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this technical solution.

[0086] In all the scenarios provided in this technical solution, it should be understood that the division of circuits or units is merely a logical functional division. In actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the displayed or discussed mutual couplings, direct couplings, or communication connections may be indirect couplings or communication connections through some interfaces, devices, or units, and may be electrical, mechanical, or other forms.

[0087] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this technical solution according to actual needs.

[0088] Furthermore, in each case of this technical solution, the functional units can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit. If the integrated circuit / unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, this technical solution can also implement all or part of the processes described above by instructing related hardware through a computer program.

[0089] The various situations described above are only used to illustrate the technical solution of this technical solution, and not to limit it. Although this technical solution has been described in detail with reference to the foregoing situations, those skilled in the art should understand that they can still modify the technical solutions described in the foregoing situations, or make equivalent substitutions for some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions in the various situations of this technical solution, and should all be included within the protection scope of this technical solution.

Claims

1. An audio processing system, characterized in that, include: The first audio processing circuit (10) is used to perform frequency division processing on the audio input signal according to the frequency division point to obtain a low-frequency signal; At least one air-conducting transducer (100) is connected to the first audio processing circuit (10) for generating sound waves based on the low-frequency signal and transmitting them to the user via the air; The second audio processing circuit (20) is used to perform frequency division processing on the audio input signal according to the frequency division point to obtain a high-frequency signal; At least one bone conduction transducer (200) is connected to the second audio processing circuit (20) for generating mechanical vibrations based on the high-frequency signal and transmitting them to the user via the human skeleton.

2. The audio processing system as described in claim 1, characterized in that, The first audio processing circuit (10) includes: The low-pass filter unit (110) is used to perform low-pass filtering on the audio input signal according to the frequency division point to obtain a low-frequency component signal.

3. The audio processing system as described in claim 2, characterized in that, The first audio processing circuit (10) further includes: The first equalization compensation unit (120) is connected to the low-pass filter unit (110) and is used to correct the amplitude of different frequencies in the low-frequency component signal according to the measured frequency response curve and the target frequency response curve to obtain a low-frequency equalization compensation signal.

4. The audio processing system as described in claim 3, characterized in that, The first audio processing circuit (10) further includes: The first phase alignment unit (130) is connected to the first equalization compensation unit (120) and is used to perform phase compensation on the low-frequency equalization compensation signal to obtain a low-frequency phase compensation signal so that the low-frequency signal and the high-frequency signal are phase aligned at the frequency division point.

5. The audio processing system as described in claim 4, characterized in that, The first audio processing circuit (10) further includes: The first amplification unit (140) is connected to the first phase alignment unit (130) and is used to adjust the gain of the low-frequency phase compensation signal according to the sensitivity and conversion efficiency of the air conduction transducer (100) to obtain the low-frequency signal. The first amplification unit (140) is connected to the air conduction transducer (100) and is used to send the low-frequency signal to the air conduction transducer (100).

6. The audio processing system as described in claim 1, characterized in that, The second audio processing circuit (20) includes: The high-pass filter unit (210) is used to perform high-pass filtering on the audio input signal according to the frequency division point to obtain the high-frequency component signal.

7. The audio processing system as described in claim 6, characterized in that, The second audio processing circuit (20) further includes: The second equalization compensation unit (220) is connected to the high-pass filter unit (210) and is used to correct the amplitude of different frequencies in the high-frequency component signal to obtain a high-frequency equalization compensation signal.

8. The audio processing system as described in claim 7, characterized in that, The second audio processing circuit (20) further includes: The second phase alignment unit (230) is connected to the second equalization compensation unit (220) and is used to perform phase compensation on the high-frequency equalization compensation signal to obtain a high-frequency phase compensation signal so that the high-frequency signal and the low-frequency signal are phase aligned at the frequency division point.

9. The audio processing system as described in claim 8, characterized in that, The second audio processing circuit (20) further includes: The second amplification unit (240) is connected to the second phase alignment unit (230) and is used to adjust the gain of the high-frequency phase compensation signal according to the sensitivity and conversion efficiency of the bone conduction transducer (200) to obtain the high-frequency signal; The second amplification unit (240) is connected to the bone conduction transducer (200) and is used to send the high-frequency signal to the bone conduction transducer (200).

10. The audio processing system as described in any one of claims 1 to 9, characterized in that, The frequency division point is determined based on the approximate condition of the acoustic dipole corresponding to the air conduction transducer (100).

11. An audio processing method, characterized in that, include: Obtain audio input signal; The first audio processing circuit (10) performs frequency division processing on the audio input signal according to the frequency division point to obtain a low-frequency signal, and transmits the low-frequency signal to the air conduction transducer (100). The air-conducting transducer (100) generates sound waves based on the low-frequency signal and transmits them to the user through the air; The second audio processing circuit (20) performs frequency division processing on the audio input signal according to the frequency division point to obtain a high-frequency signal, and transmits the high-frequency signal to the bone conduction transducer (200). The bone conduction transducer (200) generates mechanical vibrations based on the high-frequency signal and transmits them to the user through the human skeleton.

12. A type of smart glasses, characterized in that, The device includes an audio processing system as described in any one of claims 1 to 10 and a glasses body (300), wherein the audio processing system is disposed on the glasses body (300).

13. The smart glasses as described in claim 12, characterized in that, In the audio processing system, the air conduction transducer (100) and the bone conduction transducer (200) are spaced apart and arranged on the same temple (310) of the eyeglass body (300). When a user wears smart glasses, the air conduction transducer (100) is located between the user's temporal region and auricle (400), and is positioned close to the auricle (400); the bone conduction transducer (200) is positioned away from the auricle (400) and is in contact with the user's skin.

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