Earphone

Abstract

An earphone, comprising a feedback microphone, an ear cup front housing, and a sound outlet nozzle. An accommodating groove of the ear cup front housing is in communication with the sound outlet nozzle; the accommodating groove accommodates a first speaker and a second speaker; the sound outlet nozzle, the first speaker, and the second speaker are sequentially arranged; the feedback microphone is arranged at the sound outlet nozzle so to be as close as possible to the eardrum of an earphone wearer; the sound captured by the feedback microphone is closer to the sound heard by the earphone wearer, and the earphone can adjust phase-inverted ambient noise in real time on the basis of the sound captured by the feedback microphone; the first speaker is arranged between the sound outlet nozzle and the second speaker, and compared with the second speaker, the phase-inverted ambient noise generated by the first speaker has a smaller phase deviation when the phase-inverted ambient noise propagates to the eardrum of the earphone wearer; and when the first speaker and the second speaker simultaneously participate in active noise reduction, the phase-inverted ambient noise generated by the first speaker can compensate for the phase deviation of the phase-inverted ambient noise generated by the second speaker when the phase-inverted ambient noise propagates to the eardrum.

Description

A type of headphone

[0001] This application claims priority to Chinese Patent Application No. 202411726624.1, filed on November 27, 2024, entitled "An Earphone", the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of terminal technology, and in particular to a pair of headphones. Background Technology

[0003] As headphones have evolved, consumers are paying more and more attention to the user experience and demanding that headphones have good active noise cancellation performance.

[0004] When headphones perform active noise cancellation, they play an out-of-phase audio signal with the same amplitude but opposite phase as the ambient noise through the headphone speakers to cancel out the ambient noise, thus reducing the noise heard by the headphone wearer. Currently, headphones are not very effective at canceling out ambient noise with out-of-phase audio signals, resulting in poor active noise cancellation performance. Summary of the Invention

[0005] This application provides an example of an earphone with good active noise cancellation performance.

[0006] This application provides an earphone, including a feedback microphone, an earbud front shell, and a sound outlet. The sound outlet is connected to the outer surface of the earbud front shell, and the feedback microphone is housed within the sound outlet. The earbud front shell has a receiving groove communicating with the sound outlet. The receiving groove is used to house a first speaker and a second speaker. The sound frequency of the first speaker is in a first frequency band, and the sound frequency of the second speaker is in a second frequency band. The minimum sound frequency in the first frequency band is greater than the minimum sound frequency in the second frequency band, and the maximum sound frequency in the first frequency band is greater than the maximum sound frequency in the second frequency band. The second speaker is spaced apart from the sound outlet, and the first speaker is located between the sound outlet and the second speaker.

[0007] During active noise cancellation, the headphones use a feedback microphone to collect ambient noise. The first speaker generates inverse ambient noise (with equal amplitude but opposite phase to the ambient noise; specifically, the phase difference between the inverse ambient noise and the ambient noise is approximately 180°) based on the ambient noise collected by the feedback microphone to achieve active noise cancellation. The second speaker also generates inverse ambient noise based on the ambient noise collected by the feedback microphone to achieve active noise cancellation. There is a certain distance between the first speaker and the wearer's eardrum, so the phase of the inverse ambient noise generated by the first speaker will be off when it reaches the eardrum. Similarly, there is a certain distance between the second speaker and the wearer's eardrum, so the phase of the inverse ambient noise generated by the second speaker will also be off when it reaches the eardrum. The sound emitted by the first and second speakers travels through the sound outlet to the eardrum of the headphone wearer. A feedback microphone is located at the sound outlet. This microphone collects ambient noise, the sound emitted by the first and second speakers, and the first and second speakers can adjust their ambient noise levels in real time based on the combined sounds collected by the feedback microphone. The sound outlet is closer to the eardrum than the front of the earpiece, allowing the sound from the first and second speakers, along with the ambient noise, to more closely resemble the sound heard by the headphone wearer. Therefore, the real-time adjustment of the ambient noise by the first and second speakers based on the feedback microphone enhances the active noise cancellation performance of the headphones.

[0008] The first speaker is positioned between the sound outlet and the second speaker. The minimum frequency of sound emission in the first frequency band is greater than the minimum frequency of sound emission in the second frequency band, and the maximum frequency of sound emission in the first frequency band is greater than the maximum frequency of sound emission in the second frequency band. The overall frequency of sound emission from the first speaker is higher than that from the second speaker. For example, if the first speaker's frequency is in the mid-to-high frequency range (300Hz-20000Hz) and the second speaker's frequency is in the low frequency range (10Hz-10000Hz), when the headphones are performing active noise cancellation, both the first and second speakers can participate simultaneously. For instance, when using headphones in a low-frequency, high-noise environment (such as the noise from airplanes, buses crossing bumps, trains passing through tunnels, or doors closing), the energy of the opposing ambient noise output from a single speaker cannot cancel out this low-frequency, high-noise environment. By having both the first and second speakers participate in active noise cancellation (both emitting opposing ambient noise to jointly cancel out the low-frequency, high-noise environment), the low-frequency output capability of the headphones is improved, thereby enhancing the noise cancellation effect in low-frequency, high-noise environments. The second speaker is specifically designed to generate low-frequency (second frequency band) sound. When emitting low-frequency out-of-phase ambient noise, the phase change amplitude of the out-of-phase ambient noise generated by the second speaker varies more significantly with frequency compared to the first speaker (this is determined by the hardware performance of the first and second speakers; the second speaker is specifically designed for low-frequency sound, and its phase sensitivity to frequency changes is higher within the second frequency band). The deviation of the out-of-phase ambient noise generated by the second speaker from the eardrum reference point is also larger. In contrast, the deviation of the out-of-phase ambient noise generated by the first speaker from the eardrum reference point is smaller. Furthermore, compared to the second speaker, the first speaker is closer to the sound outlet, meaning it is closer to the eardrum of the headphone wearer. Therefore, the propagation path of the out-of-phase ambient noise emitted by the first speaker to the eardrum is shorter, and the phase deviation caused by the out-of-phase ambient noise from the first speaker is also smaller. When both the first and second speakers participate in active noise cancellation, the out-of-phase ambient noise generated by the first speaker can compensate for the phase deviation of the out-of-phase ambient noise generated by the second speaker as it propagates to the eardrum reference point, further improving the active noise cancellation performance of the headphones. It should be noted that the bass and mid-high frequencies here are not strictly defined by frequency; the frequency of the sound emitted by the first speaker can be lower than the frequency of the sound emitted by the second speaker.

[0009] In conjunction with the first aspect, in one possible implementation, the sound outlet includes a bottom wall and a peripheral sidewall surrounding the bottom wall. The bottom wall is spaced apart from the front shell of the earpiece, and the peripheral sidewall connects the bottom wall and the front shell of the earpiece. The rear feedback microphone is fixedly connected to the bottom wall. When the wearer uses the headphones, the closer the rear feedback microphone is to the wearer's eardrum, the closer the sound collected by the feedback microphone is to the sound heard by the wearer. Therefore, connecting the rear feedback microphone to the bottom wall further brings it closer to the wearer's eardrum. The first speaker and the second speaker adjust the anti-phase ambient noise in real time based on the sound collected by the rear feedback microphone, which further improves the active noise cancellation performance of the headphones.

[0010] In conjunction with the first aspect, in one possible implementation, the first speaker is positioned at the connection between the sound outlet and the front shell of the earpiece. With the first speaker located at this connection, it is closer to the feedback microphone, allowing for more accurate sound pickup from the first speaker. Furthermore, when the first speaker generates anti-phase ambient noise, the phase deviation from the first speaker to the feedback microphone is smaller. This allows the anti-phase ambient noise generated by the first speaker to better cancel out ambient noise at the wearer's eardrum, thereby improving the active noise cancellation effect of the headphones.

[0011] In conjunction with the first aspect, in one possible implementation, the earpiece front shell has a first rear vent hole, which communicates with the inner cavity of the first speaker. The first rear vent hole can leak the sound generated by the first speaker to the outside of the receiving groove, thereby preventing acoustic short circuits in the sound generated by the first speaker. The first rear vent hole can also leak bass frequencies, which helps improve the bass performance of the headphones. The bass frequencies can be sounds with a frequency range of 10Hz-10000Hz.

[0012] In conjunction with the first aspect, in one possible implementation, the earbud front shell includes a platform and a side surface. The side surface surrounds and connects to the platform, the sound outlet is connected to the platform, and the first rear vent hole is disposed on the platform. Since the first speaker is located at the connection between the sound outlet and the earbud front shell, and the sound outlet is connected to the platform, the first speaker is relatively close to the platform, and the first rear vent hole located on the platform is relatively close to the first speaker. This results in a shorter propagation path for the sound generated by the first speaker from its internal cavity to the first rear vent hole, facilitating the sound from the first speaker to escape from the receiving slot and improving the bass performance of the first speaker. Because the first rear vent hole is relatively close to the sound outlet, the earplug fitted over the sound outlet can cover the first rear vent hole, improving the aesthetics of the headphones.

[0013] In conjunction with the first aspect, in one possible implementation, the earpiece front shell includes a platform and a side surface, the side surface surrounds and is connected to the platform, the sound outlet is connected to the platform, and the first rear vent hole is disposed on the side surface to facilitate the opening of the first rear vent hole.

[0014] In conjunction with the first aspect, in one possible implementation, the headphones further include a venting conduit disposed between the first speaker and the second speaker. The inner cavity of the first speaker has an opening facing the second speaker, and the venting conduit connects the first venting hole and the opening. The venting conduit can improve the leakage rate of the sound produced by the first speaker, thereby enhancing the bass performance of the headphones. By placing the venting conduit between the first and second speakers, the gap between them is effectively utilized, compressing the Z-axis space of the headphones. The Z-axis of the headphones is the direction in which the first and second speakers are arranged alternately.

[0015] In conjunction with the first aspect, in one possible implementation, the headphones further include a rear venting channel. The earcup front shell includes a platform and a side surface, the side surface surrounding and connecting to the platform. The sound outlet is connected to the platform. The inner cavity of the first speaker has an opening facing the side surface. The rear venting channel connects the first rear vent hole and the opening. The rear venting channel is disposed between the opening and the first rear vent hole, and does not occupy the Z-direction space of the headphones. The Z-direction of the headphones is the direction in which the first speaker and the second speaker are arranged at intervals. The spacing between the first speaker and the second speaker can be set smaller, thereby compressing the Z-direction space of the headphones.

[0016] In conjunction with the first aspect, in one possible implementation, the first rear vent hole is also connected to the inner cavity of the second speaker. The first speaker and the second speaker share the first rear vent hole, which is used to discharge the bass generated by the first speaker and the bass generated by the second speaker, thereby improving the bass performance of the headphones while simplifying the headphone structure.

[0017] In conjunction with the first aspect, in one possible implementation, the second speaker further includes a through-hole that connects to the inner cavity of the first speaker and is also connected to the first rear vent hole. By providing a through-hole in the second speaker, the first rear vent hole can communicate with the inner cavity of the first speaker, allowing the sound generated by both the first and second speakers to be discharged. This improves the bass performance of the headphones while simplifying their structure.

[0018] In conjunction with the first aspect, in one possible implementation, the front shell of the earcup is provided with a second rear vent hole, which communicates with the inner cavity of the second speaker. The first speaker uses the first rear vent hole for sound leakage, and the second speaker uses the second rear vent hole for sound leakage, facilitating bass leakage during earphone use and improving the earphone's bass performance. Attached Figure Description

[0019] Figure 1 is a cross-sectional view of an earphone provided in an embodiment of this application;

[0020] Figure 2 is a schematic diagram of the first and second frequency bands provided in a coordinate system according to an embodiment of this application;

[0021] Figure 3 is a schematic diagram of the frequency-sound pressure curve in the headphones provided in the embodiments of this application;

[0022] Figure 4 is a schematic diagram of a usage scenario for an earphone provided in this application;

[0023] Figure 5 is a schematic diagram of the frequency-phase curve in the earphone provided in the embodiment of this application;

[0024] Figure 6 is a schematic diagram of the active noise cancellation structure of the headphones provided in the embodiment of this application;

[0025] Figure 7 is a three-dimensional structural diagram of an earphone provided in an embodiment of this application;

[0026] Figure 8 is a schematic diagram of the connection between the first speaker and the rear venting pipe in an earphone according to an embodiment of this application;

[0027] Figure 9 is a schematic diagram of the structure of a rear bleed channel in an earphone according to an embodiment of this application;

[0028] Figure 10 is a schematic diagram of the structure of a first speaker in an earphone according to an embodiment of this application;

[0029] Figure 11 is a schematic cross-sectional view of another earphone provided in an embodiment of this application;

[0030] Figure 12 is a three-dimensional structural diagram of another type of earphone provided in an embodiment of this application;

[0031] Figure 13 is a three-dimensional structural diagram of another type of earphone provided in an embodiment of this application;

[0032] Figure 14 is a schematic diagram of the connection between the first speaker and the rear venting pipe in another type of earphone provided in an embodiment of this application;

[0033] Figure 15 is a schematic diagram of another earphone rear bleed pipe connection provided in an embodiment of this application;

[0034] Figure 16 is a three-dimensional structural diagram of another type of earphone provided in an embodiment of this application;

[0035] Figure 17 is a cross-sectional view of another type of headphone provided in an embodiment of this application.

[0036] Explanation of reference numerals in the attached drawings: N1, First ambient noise; N2, Second ambient noise; 10, Front feedback microphone; 20, Earpiece front shell; 21, First rear vent hole; 22, Tabletop; 22a, Side; 23, Second rear vent hole; 24, Rear vent pipe; 24a, First port; 24b, Second port; 25, Front vent hole; 26, Filter screen; 30, Sound outlet; 31, Sound outlet; 32, Bottom wall; 33, Peripheral side wall; 40, Receiving groove; 40a, First front feedback module; 41, First speaker; 41a, Opening; 42, First secondary path; 43, First rear feedback module; 44, First primary channel estimation module; 45, Second front feedback module; 46, Second speaker; 46a, Through hole; 47, Second secondary path; 48, Second rear feedback module; 49, Second primary channel estimation module; 50, Rear feedback microphone; 60, Earpiece rear shell. Detailed Implementation

[0037] To more clearly illustrate the technical solutions in the embodiments or background art of this application, the application will be further described in detail below with reference to the accompanying drawings.

[0038] This application provides an earphone, as shown in Figure 1. The earphone includes a feedback microphone 50, an earbud shell 20, and a sound outlet 30. The sound outlet 30 is disposed on the outer surface of the earbud shell 20 and connected to the outer surface of the earbud shell 20. The feedback microphone 50 is housed within the sound outlet 30. The earbud shell 20 has a receiving groove 40 communicating with the sound outlet 30; the receiving groove 40 is used to house a first speaker 41 and a second speaker 46. When the earphone plays sound through the first speaker 41 and the second speaker 46, the first speaker 41 can produce mid-high frequencies, and the second speaker 46 can produce low frequencies. The sound frequency of the first speaker 41 is within a first frequency band, and the sound frequency of the second speaker 46 is within a second frequency band. The minimum sound frequency in the first frequency band is greater than the minimum sound frequency in the second frequency band, and the maximum sound frequency in the first frequency band is greater than the maximum sound frequency in the second frequency band. For example, referring to Figure 2, the first frequency band is [a1, a2], where a1 represents the minimum sound frequency in the first frequency band, and a2 represents the maximum sound frequency in the first frequency band. The second frequency band is [b1, b2], where b1 represents the minimum sound frequency in the second frequency band, and b2 represents the maximum sound frequency in the second frequency band. a1 is greater than b1, and a2 is greater than b2. In some embodiments, b1 < a1 ≤ b2 < a2, the first frequency band can be 300Hz-20000Hz, and the second frequency band can be 10Hz-10000Hz. It should be noted that the frequency of the sound emitted by the first speaker 41 is generally higher than the frequency of the sound emitted by the second speaker 46. When the first speaker 41 and the second speaker 46 produce sound, the sound frequency of the second speaker 46 can also be higher than the sound frequency of the first speaker 41. The first speaker 41 can be, but is not limited to, a moving-coil speaker, a planar diaphragm speaker, or a micro-electro-mechanical system (MEMS) speaker. The second speaker 46 can be, but is not limited to, a moving speaker or a dual-diaphragm speaker.

[0039] Please refer to Figure 3, which is a schematic diagram of the frequency-sound pressure curve in the headphones provided in this embodiment of the application. In the coordinate system, the horizontal axis represents frequency, and the vertical axis represents sound pressure in the headphones. The first speaker 41 is responsible for reproducing mid-high frequencies (sounds within the first frequency band), and the second speaker 46 is responsible for reproducing low frequencies (sounds within the second frequency band). Since the second speaker 46 is dedicated to low-frequency reproduction, the bass performance of the headphones can be improved. In particular, within the 10Hz-1000Hz range, the sound pressure of the headphones can be effectively increased, thereby improving the user experience.

[0040] Referring to Figures 1 and 4, the second speaker 46 is spaced apart from the sound outlet 30, and the first speaker 41 is located between the sound outlet 30 and the second speaker 46. Compared to the second speaker 46, the first speaker 41 is closer to the sound outlet 30. When the user wears the headphones, the sound outlet 30 of the headphones extends into the ear of the headphone wearer. Therefore, the first speaker 41 is closer to the eardrum reference point (DRP) of the headphone wearer than the second speaker 46.

[0041] When the headphones perform active noise cancellation, they collect ambient noise through the feedback microphone 10. The first speaker 41 can generate anti-phase ambient noise (the anti-phase ambient noise has the same amplitude and opposite phase to the ambient noise, and the phase difference between the anti-phase ambient noise and the ambient noise is close to 180°) based on the ambient noise collected by the feedback microphone 10 to achieve active noise cancellation. The second speaker 46 can also generate anti-phase ambient noise based on the ambient noise collected by the feedback microphone 10 to achieve active noise cancellation. In this application, the first speaker 41 and the second speaker 46 can participate in active noise cancellation simultaneously. For example, when the headphones play sound in a low-frequency, high-noise environment, in order to improve the low-frequency output capability of the headphones, while the first speaker 41 participates in active noise cancellation (the first speaker 41 generates anti-phase ambient noise based on the feedback microphone), the second speaker 46 also participates in active noise cancellation (the second speaker 46 generates anti-phase ambient noise based on the feedback microphone). When the headphones are performing active noise cancellation, either the first speaker 41 or the second speaker 46 can participate in active noise cancellation (generating inverse ambient noise based on the ambient noise collected by the feedback microphone). For example, if the ambient noise frequency is in the first frequency band, the first speaker 41 can participate in active noise cancellation while the second speaker 46 does not. Similarly, if the ambient noise frequency is in the second frequency band, the second speaker 46 can participate in active noise cancellation while the first speaker 41 does not. Whether the first speaker 41 and / or the second speaker 46 participates in active noise cancellation can be selected based on the amplitude and frequency of the ambient noise when the headphones are playing sound.

[0042] In this application, when the headphones play sound in a low-frequency, high-noise environment, the first speaker 41 and the second speaker 46 can simultaneously participate in active noise cancellation. Since the second speaker 46 is specifically designed to generate low-frequency sounds (sounds within the second frequency band), when emitting low-frequency anti-phase ambient noise, the phase change amplitude of the anti-phase ambient noise generated by the second speaker 46, relative to the first speaker 41, changes more significantly with the frequency (this is determined by the hardware performance of the first and second speakers 41; the second speaker 46 is specifically designed to generate low-frequency sounds. Within the second frequency band, the phase of the sound emitted by the second speaker 46 is more sensitive to frequency changes). As a result, the deviation of the anti-phase ambient noise generated by the second speaker 46 from the eardrum reference point of the headphone wearer is also larger, while the deviation of the anti-phase ambient noise generated by the first speaker 41 from the eardrum reference point is smaller. Simultaneously, compared to the second speaker 46, the first speaker 41 is closer to the sound outlet, meaning it is closer to the eardrum reference point of the headphone wearer. Compared to the second speaker 46, the first speaker 41 has a shorter propagation path for its out-of-phase ambient noise to reach the eardrum reference point of the headphone wearer. The phase deviation caused by this out-of-phase ambient noise is also smaller. The out-of-phase ambient noise generated by the first speaker 41 can compensate for the phase deviation of the out-of-phase ambient noise generated by the second speaker 46, further improving the active noise cancellation performance of the headphones. Please refer to Figure 5, which is a schematic diagram of the frequency-phase curve in the headphones provided in this embodiment. In Figure 5, the horizontal axis represents frequency, and the vertical axis represents phase. The out-of-phase ambient noise generated by the second speaker varies significantly with the sound frequency, and is prone to abrupt changes, resulting in a large phase deviation. Compared to the second speaker 46, the phase of the anti-phase ambient noise generated by the first speaker 41 changes less with the change of sound frequency in the second frequency band, and the phase deviation of the anti-phase ambient noise generated by the first speaker 41 with the change of frequency is also smaller. When both the first speaker 41 and the second speaker 46 participate in active noise cancellation, the anti-phase ambient noise generated by the first speaker 41 can compensate for the phase difference of the anti-phase ambient noise generated by the second speaker 46 propagating to the eardrum reference point, thereby improving the active noise cancellation performance of the headphones.

[0043] Referring again to Figure 4, there is a certain distance between the first speaker 41 and the eardrum reference point of the earphone wearer. When the anti-phase ambient noise generated by the first speaker 41 reaches the eardrum reference point, its phase will deviate. The first speaker 41 can also adjust the anti-phase ambient noise in real time based on the sound collected by the feedback microphone 50 (ambient noise, the sound emitted by the first speaker 41, and the sound emitted by the second speaker 46). Similarly, there is a certain distance between the second speaker 46 and the eardrum reference point of the earphone wearer. When the anti-phase ambient noise generated by the second speaker 46 reaches the eardrum reference point, its phase will also deviate. The second speaker 46 can also adjust the anti-phase ambient noise in real time based on the sound collected by the feedback microphone 50 (ambient noise, the sound emitted by the first speaker 41, and the sound emitted by the second speaker 46). In this application, the sound outlet 30 is closer to the eardrum reference point of the headphone wearer than the earpiece front shell 20. The rear feedback microphone 50 is located inside the sound outlet. Since the rear feedback microphone 50 is relatively close to the eardrum reference point of the headphone wearer, the sound emitted by the first speaker 41, the sound emitted by the second speaker 46, and the ambient noise collected by the rear feedback microphone 50 are closer to the sound heard by the headphone wearer. Therefore, the first speaker 41 and the second speaker 46 adjust the anti-phase ambient noise according to the sound collected by the rear feedback microphone 50, which can improve the active noise cancellation performance of the headphones.

[0044] When the headphones play sound, they receive a first downlink signal and / or a second downlink signal from an electronic device. Specifically, the first speaker 41 plays a first pre-playback sound based on the first downlink signal, and the second speaker 46 plays a second pre-playback sound based on the second downlink signal. When the headphones perform active noise cancellation, environmental noise can be divided into first environmental noise and second environmental noise. First environmental noise can be understood as noise outside the headphones. For example, if the headphone wearer is in an area where there are other objects or living beings besides the headphones, the sounds produced by these objects or living beings can be called first environmental noise. Second environmental noise can be understood as noise generated within the headphones. For example, during the playback of sound through the first speaker 41 and the second speaker 46, the first speaker 41 and the second speaker 46 generate noise. The noise generated within the headphones by the first speaker 41 and the second speaker 46 due to sound playback can be called second environmental noise.

[0045] The anti-phase ambient noise can include a first anti-phase ambient noise and a second anti-phase ambient noise. The first anti-phase ambient noise is used to cancel the first ambient noise, and the second anti-phase ambient noise is used to cancel the second ambient noise. When the headphones perform active noise cancellation, the feedback microphone 10 collects the first ambient noise and generates the first anti-phase ambient noise through at least one of the first speaker 41 and the second speaker 46, and uses the first anti-phase ambient noise to cancel the first ambient noise.

[0046] If the frequency of the first ambient noise is within the first frequency band, after the first ambient noise is collected by the front feedback microphone 10, the first speaker 41 generates a first anti-phase ambient noise based on the first ambient noise, and uses the first anti-phase ambient noise generated by the first ambient noise to cancel the first ambient noise.

[0047] If the frequency of the first ambient noise falls within both the first and second frequency bands, the first speaker 41 can be used to generate the first anti-phase ambient noise. Compared to the second speaker 46, the first speaker 41 is closer to the eardrum reference point of the headphone wearer. When the first anti-phase ambient noise generated by the first speaker 41 propagates to the eardrum reference point of the headphone wearer, the phase deviation will be smaller, and the effect of the first anti-phase ambient noise generated by the first speaker 41 in canceling the first ambient noise will be better.

[0048] If the frequency of the first ambient noise is within the second frequency band, after the first ambient noise is collected by the front feedback microphone 10, the second speaker 46 can be selected to generate the first anti-phase ambient noise, and the first anti-phase ambient noise generated by the first ambient noise can be used to cancel the first ambient noise. Specifically, the second speaker 46 generates the first anti-phase ambient noise based on the first ambient noise.

[0049] If the frequency of the first ambient noise is within the second frequency band, but the amplitude of the first ambient noise is very large (e.g., the noise generated by airplanes, buses going over bumps, trains passing through tunnels, and doors closing), after the first ambient noise is collected by the feedback microphone 10, the first speaker 41 and the second speaker 46 can be selected to simultaneously generate the first anti-phase ambient noise. The energy of this first ambient noise is very large, and the energy generated by a single speaker is limited. The first anti-phase ambient noise emitted by a single speaker has a poor cancellation effect on the first ambient noise. By using the first anti-phase ambient noise generated by the first speaker 41 and the first anti-phase ambient noise generated by the second speaker 46 to cancel the first ambient noise together, the active noise reduction performance in low-frequency, high-noise (sound with low frequency and large amplitude) scenarios can be improved.

[0050] Please refer to Figure 6. The feedback microphone 50 can collect the first ambient noise N1, the second ambient noise N2, the first pre-playback sound emitted by the first speaker 41, and the second pre-playback sound emitted by the second speaker 46.

[0051] The feedback microphone 50 can feed back the first ambient noise N1, the second ambient noise N2, the first pre-playback sound, and the second pre-playback sound to the first speaker 41. The first speaker 41 can generate a second anti-phase ambient noise based on the second ambient noise N1. The feedback microphone 50 can also feed back the first ambient noise N1, the second ambient noise N2, the first pre-playback sound, and the second pre-playback sound to the second speaker 46. The second speaker 46 can generate a second anti-phase ambient noise based on the second ambient noise N2. In some embodiments, when the headphones perform active noise cancellation, at least one of the first speaker 41 and the second speaker 46 can be selected to generate the second anti-phase ambient noise N2, and the second anti-phase ambient noise can be used to cancel the second ambient noise N2. For example, only the first speaker 41 can be used to generate the second anti-phase ambient noise, and the second anti-phase ambient noise generated by the first speaker 41 can be used to cancel the second ambient noise; or only the second speaker 46 can be used to generate the second anti-phase ambient noise, and the second anti-phase ambient noise generated by the second speaker 46 can be used to cancel the second ambient noise N2. It is also possible to have both the first speaker 41 and the second speaker 46 generate second phase-inverse ambient noise, and use the second phase-inverse ambient noise generated by the first speaker 41 and the second phase-inverse ambient noise generated by the second speaker 46 to jointly cancel the second ambient noise N2.

[0052] When the frequency of the second ambient noise N2 is within the first frequency band, the first speaker 41 can be selected to generate the second anti-phase ambient noise, and the second anti-phase ambient noise generated by the first speaker 41 can be used to cancel the second ambient noise.

[0053] When the frequency of the second ambient noise N2 falls within both the first and second frequency bands, the first speaker 41 can be selected to generate a second anti-phase ambient noise to cancel out the second ambient noise N2. Compared to the second speaker 46, the first speaker 41 is closer to the eardrum reference point of the headphone wearer. Therefore, the phase deviation of the second anti-phase ambient noise emitted by the first speaker 41 reaching the eardrum reference point is smaller, resulting in a better cancellation effect for the second ambient noise N2.

[0054] When the frequency of the second ambient noise N2 is within the second frequency band, the second speaker 46 can be selected to generate the second anti-phase ambient noise, and the second anti-phase ambient noise generated by the second speaker 46 can be used to cancel the second ambient noise.

[0055] The path from the first speaker 41 to the feedback microphone 50 forms a first secondary path (SP) 42, and the path from the second speaker 46 to the feedback microphone 50 forms a second secondary path 47.

[0056] In some embodiments, the headphones further include a first feed-forward (FF) module 40a and a second feed-forward (FF) module 45. The FF microphone 10 transmits the collected first ambient noise N1 to the first FF module 40a and the second FF module 45, respectively. The first FF module 40a generates a first inverted ambient noise signal based on the first ambient noise N1 and transmits the first inverted ambient noise signal to the first speaker 41. The first speaker 41 generates first inverted noise based on the first inverted ambient noise signal. The second FF module 45 generates the first inverted ambient noise signal based on the first ambient noise N1 and transmits the first inverted ambient noise signal to the second speaker 46. The second speaker 46 generates first inverted noise based on the first inverted ambient noise signal.

[0057] In the first secondary path 42, the first inverted ambient noise signal and the first downlink signal are mixed by a mixer, and the first speaker 41 generates a first frequency band sound (mixed mid-high frequencies) based on the first inverted ambient noise signal and the first downlink signal.

[0058] In the second secondary path 47, the first inverted ambient noise signal and the second downlink signal are mixed by a mixer, and the second speaker 46 generates a second frequency band sound (mixed bass) based on the first inverted ambient noise signal and the second downlink signal.

[0059] When the mixed mid-high frequency reaches the feedback microphone 50 from the first speaker 41, the feedback microphone 50 collects the mixed mid-high frequency and the first ambient noise N1. After canceling the first ambient noise N, the mixed mid-high frequency retains the first pre-playback sound (the first pre-playback sound can be converted from the first downlink signal). At this time, the feedback microphone 50 collects the sound after subtracting the first ambient noise N1 from the mixed mid-high frequency (e.g., the first pre-playback sound).

[0060] When the mixed bass reaches the feedback microphone 50 from the second speaker 46, the feedback microphone 50 collects the mixed bass and the first ambient noise N. After canceling the first ambient noise N, the mixed bass retains the second pre-playback sound (the second pre-playback sound can be converted from the second downlink signal). At this time, the feedback microphone 50 collects the mixed bass minus the first ambient noise N1 (e.g., the second pre-playback sound).

[0061] The headphones contain sound-generating devices such as a first speaker and a second speaker. When the headphones play sound, there is a second ambient noise. When the second ambient noise reaches the feedback microphone 50, the feedback microphone 50 collects the second ambient noise.

[0062] The headset also includes a secondary path estimation (SPE) module 44. The input of the secondary path estimation module 44 is used to receive the first downlink signal, and the output of the secondary path estimation module 44 is connected to the post-feedback microphone 50 through a mixer.

[0063] The headset also includes a secondary path estimation (SPE) module 49. The input of the secondary path estimation module 49 is used to receive the second downlink signal, and the output of the secondary path estimation module 49 is connected to the post-feedback microphone 50 via a mixer. The primary path estimation module 44 and the secondary path estimation module 49 are communicatively connected.

[0064] It should be noted that the sound acquired by the feedback microphone 50 includes a mixture of mid-high frequencies, a first ambient noise N1, a second ambient noise N2, and a mixture of bass frequencies. The feedback microphone 50 converts the acquired sound into a mixed electrical signal. Since the mixed mid-high frequencies cancel out the first ambient noise N1, the remaining sound is the first pre-playback sound (corresponding to the first downlink signal), and the mixed bass frequencies cancel out the first ambient noise N1, the remaining sound is the second pre-playback sound (corresponding to the second downlink signal). Therefore, the mixed electrical signal includes the first downlink signal, the second downlink signal, and the second ambient noise signal N2. The mixed electrical signal is processed by the first-stage channel estimation module 44 and the second-stage channel estimation module 49 to obtain the second ambient noise signal.

[0065] The headphones also include a first feed-backward (FB) module 43 and a second feed-backward (FB) module 48. The first FB module 43 generates a second inverted ambient noise signal based on a second ambient noise signal and sends the second inverted ambient noise signal to a first speaker 41. The first speaker 41 can generate a mixed mid-high frequency response based on the first inverted ambient noise signal, the second inverted ambient noise signal, and the first downlink signal. In this case, the mixed mid-high frequency response can cancel out the first ambient noise N and the second ambient noise N2 to preserve the first pre-playback sound. The second FB module 48 generates a second inverted ambient noise signal based on the second ambient noise signal and sends the second inverted ambient noise signal to a second speaker 46. The second speaker 46 can generate a mixed bass response based on the first inverted ambient noise signal, the second inverted ambient noise signal, and the second downlink signal. In this case, the mixed bass response can cancel out the first ambient noise N1 and the second ambient noise N2 to preserve the second pre-playback sound.

[0066] In the embodiments provided in this application, please refer to Figures 1 and 7. The sound outlet 30 includes a bottom wall 32 and a peripheral sidewall 33 surrounding the bottom wall 32. The bottom wall 32 is spaced apart from the earpiece front shell 20, and the peripheral sidewall 33 connects the bottom wall 32 and the earpiece front shell 20. The rear feedback microphone 50 is fixedly connected to the bottom wall 32. When the wearer uses the headphones, the closer the rear feedback microphone 50 is to the wearer's eardrum reference point, the closer the sound collected by the feedback microphone 50 is to the sound heard by the wearer. Therefore, the connection of the rear feedback microphone 50 to the bottom wall 32 will further bring it closer to the eardrum reference point of the headphone wearer. In this way, the first speaker 41 and the second speaker 46 adjust the anti-phase ambient noise in real time according to the sound collected by the rear feedback microphone 50, which will further improve the active noise cancellation performance of the headphones.

[0067] In the embodiments provided in this application, the bottom wall 32 may also be provided with a sound outlet 31, which penetrates the bottom wall 32. The sound emitted by the first speaker 41 reaches the ear of the earphone wearer through the sound outlet 31, and the sound emitted by the second speaker 46 reaches the ear of the earphone wearer through the sound outlet 31.

[0068] The first speaker 41 is located at the connection between the sound outlet 30 and the front shell 20 of the earphone. Because the first speaker 41 is positioned closer to the feedback microphone 50, the feedback microphone 50 can more accurately capture the sound emitted by the first speaker 41. Furthermore, when the first speaker 41 generates anti-phase ambient noise, the phase error in the propagation of this noise from the first speaker 41 to the feedback microphone 50 is also smaller. This anti-phase ambient noise generated by the first speaker 41 can better cancel out ambient noise at the eardrum of the headphone wearer, improving the active noise cancellation effect of the headphones.

[0069] It should be noted that the sound outlet 30 has size limitations. If the sound outlet 30 is too large, it will be inconvenient to insert the earphone into the wearer's ear. The first speaker 41 needs to emit a certain volume of sound, which also has size limitations. The size of the first speaker 41 cannot be too small, and the first speaker 41 cannot be accommodated on the sound outlet 30 due to size constraints. Therefore, placing the first speaker 41 at the connection between the sound outlet 30 and the earbud front shell 20 allows the first speaker 41 to be closer to the feedback microphone 50.

[0070] Please refer to Figures 7, 8, and 9. The headphones also include a rear earcup shell 60, which is connected to the side of the front earcup shell 20 away from the sound outlet 30 and seals the receiving groove. The front earcup shell 20 has a first rear vent hole 21, which communicates with the inner cavity of the first speaker 41. The first rear vent hole 21 can prevent acoustic short circuits in the sound generated by the first speaker 41 and can leak bass frequencies, thus helping to improve the bass performance of the headphones.

[0071] The earbud front shell 20 includes a platform 22 and a side surface 22a. The side surface 22a surrounds and connects to the platform 22. The sound outlet 30 is connected to the platform 22, and the first rear vent hole 21 is disposed on the platform 22. The platform 22 can be flat. The first rear vent hole 21 is located on the platform 22, and the first speaker 41 is disposed at the connection between the sound outlet 30 and the receiving groove. Since the first speaker 41 is located at the connection between the sound outlet 30 and the earbud front shell 20, and the sound outlet 30 is connected to the platform 22, the first speaker 41 will be relatively close to the platform 22. The first rear vent hole 21 located on the platform 22 will be relatively close to the first speaker 41. The sound generated by the first speaker 41 will have a shorter propagation path from the inner cavity of the first speaker 41 to the first rear vent hole 21, which facilitates the sound generated by the first speaker 41 to be released from the first rear vent hole 21 to the outside of the receiving groove, thereby improving the bass performance of the first speaker 41. The first rear vent 21 is relatively close to the sound outlet 30. The earplug fitted onto the sound outlet 30 can cover the first rear vent 21, improving the aesthetics of the headphones.

[0072] Please refer to Figures 1, 7, 8, 9, and 10. The headphones may also include a rear venting conduit 24. The inner cavity of the first speaker 41 has an opening 41a facing the side 22a. The rear venting conduit 24 connects the first rear venting hole 21 and the opening 41a. The rear venting conduit 24 is disposed between the opening 41a and the first rear venting hole 21. The rear venting conduit 24 does not occupy the space in the Z-direction of the headphones. The Z-direction of the headphones is the direction in which the first speaker 41 and the second speaker 46 are arranged at intervals, and the Z-direction of the headphones is perpendicular to the table surface 22. The spacing between the first speaker 41 and the second speaker 46 can be set to be smaller, thereby compressing the space in the Z-direction of the headphones. Specifically, the rear venting conduit 24 is disposed on the side of the first speaker 41. The rear venting conduit 24 includes a first port 24a and a second port 24b. The first port 24a faces the side of the first speaker 41 and communicates with the opening 41a. The second port 24b faces the table surface 22 and communicates with the first rear venting hole 21. A filter screen 26 can be installed between the first rear discharge hole 21 and the second port 24b. The filter screen 26 can filter out debris and prevent debris from entering the receiving tank 40 through the first rear discharge hole 21 and the rear discharge pipe 24.

[0073] The earpiece front shell 20 may also include a second rear vent 23, which communicates with the inner cavity of the second speaker 46. Specifically, the first rear vent 21 and the second rear vent 23 are independent of each other. The first speaker 41 uses the first rear vent 21 to vent sound, and the second speaker 46 uses the second rear vent 23 to vent sound, which facilitates bass leakage during use and improves the bass performance of the headphones.

[0074] Please refer to Figures 11, 12, and 13. The first rear vent 21 can also be located on the side 22a, which facilitates its installation. The platform 22 can also be provided with a front vent 25, which is connected to the receiving groove 40. When the user uses the headphones, the front vent 25 can release pressure in the user's ear, improving comfort. Excessive pressure in the user's ear can easily cause discomfort.

[0075] The rear venting conduit 24 can be disposed between the first speaker 41 and the second speaker 46. Referring to Figures 14 and 15, the inner cavity of the first speaker 41 has an opening facing the second speaker 46. The rear venting conduit 24 connects the first rear venting hole 21 and the opening. Specifically, the rear venting conduit 24 includes a first port 24a and a second port 24b connected together. The first port 24a faces the opening and communicates with the inner cavity of the first speaker 41 through the opening. The second port 24b extends into the first rear venting hole 21. The rear venting conduit 24 can improve the leakage rate of the sound generated by the first speaker 41, thus improving the bass performance of the headphones. By disposing of the rear venting conduit 24 between the first speaker 41 and the second speaker 46, the gap between the first speaker 41 and the second speaker 46 is effectively utilized, compressing the space in the Z-direction of the headphones. The Z-direction of the headphones is the direction in which the first and second speakers are arranged alternately.

[0076] Please refer to Figures 16 and 17. In some embodiments, the first rear vent 21 is also connected to the inner cavity of the second speaker 41. The second speaker 46 can share the first rear vent 21 with the first speaker 41. Specifically, the side of the second speaker 46 facing away from the first speaker 41 is connected to the first rear vent 21. The first speaker 41 and the second speaker 46 share the first rear vent 21, using the first rear vent 21 to discharge the sound generated by the first speaker 41 and the sound generated by the second speaker 46, thereby improving the bass performance of the headphones while simplifying the headphone structure. The second speaker is also provided with a through hole 46a, which connects to the inner cavity of the first speaker 41 and is also connected to the first rear vent 21.

[0077] The leakage rate of the sound produced by the first speaker 41 can be improved by the rear venting pipe 24, thereby improving the bass performance of the headphones. The rear venting pipe 24 passes through the second speaker 46 and extends to the first rear venting hole 21 of the ear cup front shell 20. The rear venting pipe 24 does not occupy the space in the Z direction of the headphones. The Z direction of the headphones is the direction in which the first speaker 41 and the second speaker 46 are arranged alternately. The distance between the first speaker 41 and the second speaker 46 can be set to be smaller.

[0078] In some embodiments, the headphones may further include three or more speakers. For example, a receiving slot houses a first speaker, a second speaker, and a third speaker; a sound outlet, the first speaker, and the second speaker are arranged sequentially; the sound outlet houses a feedback microphone; and the third speaker is located on the side of the second speaker away from the first speaker. The first speaker emits a first frequency band, the second speaker emits a second frequency band, and the third speaker emits a third frequency band. The first frequency band can be [a1, a2], where a1 is the minimum frequency in the first frequency band, and a2 is the maximum frequency in the first frequency band. The second frequency band can be [b1, b2], where b1 is the minimum frequency in the second frequency band, and b2 is the maximum frequency in the second frequency band. The third frequency band can be [c1, c3], where c1 is the minimum frequency in the third frequency band, and c2 is the maximum frequency in the third frequency band. Wherein, b1 < c1 < a1, b2 < c2 < a2, and b2 can be greater than a1. For example, the first frequency band is 500Hz-20000Hz, the second speaker's sound frequency is 10Hz-2000Hz, and the third frequency band is 100Hz-10000Hz.

[0079] The first speaker reproduces high frequencies, the second speaker reproduces low frequencies, and the third speaker reproduces mid frequencies. In this embodiment, low, mid, and high frequencies are relative; the frequency of the first speaker can be lower than that of the third speaker, the frequency of the first speaker can be higher than that of the second speaker, and the frequency of the second speaker can be higher than that of the third speaker.

[0080] In one possible implementation, the third speaker can handle midrange reproduction but not active noise cancellation. In this case, the third speaker and the feedback microphone do not form a single point of contact (SP). The feedback microphone collects a first ambient noise, a mixed high-frequency response generated by the first speaker, a second ambient noise, a mixed low-frequency response generated by the second speaker, and a mixed midrange response. The mixed high-frequency response can cancel out the first and second ambient noise to preserve the first pre-playback sound, and the mixed low-frequency response can cancel out the first and second ambient noise to preserve the second pre-playback sound.

[0081] In another possible implementation, the third speaker can also perform midrange reproduction and active noise cancellation, and the third speaker and the feedback microphone also form a single channel (SP). For example, the feedback microphone is used to collect second ambient noise, mixed high frequencies, mixed mid frequencies, and mixed low frequencies; the first speaker is used to generate a first inverted ambient noise signal based on the first ambient noise, and is also used to generate a second inverted ambient noise signal based on the second ambient noise, and further used to generate mixed high frequencies based on the first inverted ambient noise signal, the second inverted ambient noise signal, and the first downlink signal.

[0082] The second loudspeaker is also used to generate a first inverted ambient noise signal based on the first ambient noise, and to generate a second inverted ambient noise signal based on the second ambient noise. The second loudspeaker is also used to generate a mixed bass signal based on the first inverted ambient noise signal, the second inverted ambient noise signal, and the second downlink signal.

[0083] The third loudspeaker is also used to generate a first inverted ambient noise signal based on the first ambient noise, and to generate a second inverted ambient noise signal based on the second ambient noise. The third loudspeaker is also used to generate a mixed midrange based on the first inverted ambient noise signal, the second inverted ambient noise signal and the third downlink signal.

[0084] The mixed high frequencies can cancel out the first ambient noise and the second ambient noise to preserve the first pre-playback sound (corresponding to the first downlink signal), the mixed low frequencies can cancel out the first ambient noise and the second ambient noise to preserve the second pre-playback sound (corresponding to the first downlink signal), and the mixed mid frequencies can cancel out the first ambient noise and the second ambient noise to preserve the mid frequencies (corresponding to the third downlink signal).

[0085] It should be understood that expressions such as “comprising” and “may include” used in this application indicate the existence of the disclosed functions, operations, or constituent elements, and do not limit one or more additional functions, operations, and constituent elements. In this application, terms such as “comprising” and / or “having” are to be interpreted as indicating a particular characteristic, number, operation, constituent element, component, or combination thereof, but not to exclude the existence or possibility of adding one or more other characteristics, numbers, operations, constituent elements, components, or combinations thereof.

[0086] Furthermore, in this application, the expression "and / or" includes any and all combinations of the associated listed words. For example, the expression "A and / or B" may include A, may include B, or may include both A and B.

[0087] In this application, expressions including ordinal numbers such as "first" and "second" may modify the elements. However, such elements are not limited by the foregoing expressions. For example, the foregoing expressions do not limit the order and / or importance of the elements. The foregoing expressions are only used to distinguish one element from other elements. For example, "first user equipment" and "second user equipment" refer to different user equipment, although both "first user equipment" and "second user equipment" are user equipment. Similarly, without departing from the scope of this application, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element.

[0088] When a component is referred to as "connected" or "accessed" to other components, it should be understood that this component not only connects directly to or accesses other components, but also that another component may exist between this component and other components. On the other hand, when a component is referred to as "directly connected" or "directly accessed" to other components, it should be understood that no component exists between them.

[0089] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. An earphone, characterized in that, The device includes a feedback microphone, an earbud front shell, and a sound outlet. The sound outlet is connected to the earbud front shell, and the feedback microphone is housed within the sound outlet. The earbud front shell has a receiving groove communicating with the sound outlet. The receiving groove is used to house a first speaker and a second speaker. The first speaker has a frequency in a first frequency band, and the second speaker has a frequency in a second frequency band. The minimum frequency in the first frequency band is greater than the minimum frequency in the second frequency band, and the maximum frequency in the first frequency band is greater than the maximum frequency in the second frequency band. The second speaker is spaced apart from the sound outlet, and the first speaker is located between the sound outlet and the second speaker.

2. The headphones as described in claim 1, characterized in that, The sound outlet includes a bottom wall and a peripheral side wall surrounding the bottom wall. The bottom wall is spaced apart from the front shell of the earpiece. The peripheral side wall connects the bottom wall and the front shell of the earpiece. The rear feedback microphone is fixedly connected to the bottom wall.

3. The headphones as described in claim 1 or 2, characterized in that, The first speaker is located at the connection between the sound outlet and the front shell of the earpiece.

4. The headphones as described in claim 3, characterized in that, The front shell of the earpiece has a first rear vent hole, which communicates with the inner cavity of the first speaker.

5. The headphones as described in claim 4, characterized in that, The earpiece front shell includes a platform and a side surface, the side surface surrounds the platform and is connected to the platform, the sound outlet is connected to the platform, and the first rear vent hole is disposed on the platform.

6. The headphones as described in claim 4, characterized in that, The earpiece front shell includes a platform and a side surface, the side surface surrounds the platform and is connected to the platform, the sound outlet is connected to the platform, and the first rear vent hole is disposed on the side surface.

7. The headphones as described in any one of claims 4-6, characterized in that, It also includes a rear venting conduit disposed between the first speaker and the second speaker, wherein the inner cavity of the first speaker has an opening facing the second speaker, and the rear venting conduit connects the first rear venting hole and the opening.

8. The headphones as described in any one of claims 4-6, characterized in that, It also includes a rear venting channel, the front shell of the earpiece includes a platform and a side, the side surrounds the platform and is connected to the platform, the sound outlet is connected to the platform, the inner cavity of the first speaker has an opening facing the side, and the rear venting channel connects the first rear venting hole and the opening.

9. The headphones as described in any one of claims 4-6, characterized in that, The first rear vent hole is also connected to the inner cavity of the second speaker.

10. The headphones as described in claim 9, characterized in that, The second loudspeaker is also provided with a through hole, which communicates with the inner cavity of the first loudspeaker and is also connected to the first rear vent hole.

11. The headphones as described in any one of claims 4-6, characterized in that, The front shell of the earpiece is provided with a second rear vent hole, which communicates with the inner cavity of the second speaker.

Images