Acoustic output device

Abstract

This specification provides an acoustic output device. The acoustic output device may include a bone conduction speaker configured to generate bone-conducted sound waves. The acoustic output device may also include an air conduction speaker configured to generate air-conducted sound waves, the air conduction speaker being independent of the bone conduction speaker. The acoustic output device may further include at least one housing configured to accommodate the bone conduction speaker and the air conduction speaker.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to Chinese patent application number 202010247338.2 filed on March 31, 2020, the contents of which are incorporated herein by reference. Technical Field

[0003] The present specification relates generally to an acoustic output device and, more particularly, to an acoustic output device that uses both bone conduction and air conduction to provide audio signals to a user. Background Art

[0004] Wearable acoustic output devices (such as headphones) are becoming increasingly popular. Open binaural acoustic output devices (such as bone conduction speakers) are portable audio devices that facilitate sound transmission to the user. However, bone conduction speakers exhibit poor performance in the mid- and low-frequency ranges and introduce strong vibrations, which impact the user experience, particularly comfort. Therefore, there is a desire to develop acoustic output devices that enhance the user's audio experience in the mid- and low-frequency ranges. Summary of the Invention

[0005] In one aspect of the present disclosure, an acoustic output device is provided. The acoustic output device may include a bone conduction speaker configured to generate bone-conducted sound waves; an air conduction speaker configured to generate air-conducted sound waves, the air conduction speaker being independent of the bone conduction speaker; and at least one housing configured to house the bone conduction speaker and the air conduction speaker.

[0006] In some embodiments, the bone conduction speaker includes a vibration component, which includes a magnetic circuit system configured to generate a magnetic field; a vibration plate connected to the at least one shell; and one or more coils connected to the vibration plate, wherein the one or more coils vibrate in the magnetic field and drive the vibration plate to vibrate to generate the bone conduction sound waves.

[0007] In some embodiments, the air conduction speaker includes a driver and a diaphragm, wherein the driver drives the diaphragm to vibrate to generate the air conduction sound waves.

[0008] In some embodiments, the air conduction speaker is positioned next to the bone conduction speaker.

[0009] In some embodiments, the at least one housing includes a first housing and a second housing, the bone conduction speaker is accommodated in the first housing, and the air conduction speaker is accommodated in the second housing.

[0010] In some embodiments, the vibration direction of the bone conduction speaker is a first direction, the central vibration direction of the diaphragm of the air conduction speaker is a second direction, and the first direction is parallel to the second direction.

[0011] In some embodiments, the distance from the air conduction speaker to the listening position is smaller than the distance from the bone conduction speaker to the listening position.

[0012] In some embodiments, the second housing includes a sound hole facing a listening position.

[0013] In some embodiments, the air conduction speaker and the bone conduction speaker are stacked.

[0014] In some embodiments, the vibration direction of the bone conduction speaker and the central vibration direction of the diaphragm of the air conduction speaker are the same direction.

[0015] In some embodiments, the at least one housing comprises a third housing in which the bone conduction speaker and the air conduction speaker are housed.

[0016] In some embodiments, the third shell includes a shell wall for transmitting the bone-conducted sound waves outward.

[0017] In some embodiments, the third housing includes a sound hole facing the listening position.

[0018] In some embodiments, the bone conduction speaker and the air conduction speaker are arranged vertically relative to each other.

[0019] In some embodiments, the vibration direction of the bone conduction speaker is a third direction, the central vibration direction of the diaphragm of the air conduction speaker is a fourth direction, and the third direction is substantially perpendicular to the fourth direction.

[0020] In some embodiments, the at least one housing comprises a fourth housing in which the bone conduction speaker and the air conduction speaker are housed.

[0021] In some embodiments, the bone-conducted sound waves include medium and high frequencies, and the air-conducted sound waves include medium and low frequencies.

[0022] In some embodiments, the bone-conducted sound waves include medium and low frequencies, and the air-conducted sound waves include medium and high frequencies.

[0023] In some embodiments, the air-conducted sound waves include low to medium frequencies, and the bone-conducted sound waves include frequencies within a wider frequency range than the frequencies of the air-conducted sound waves.

[0024] In some embodiments, the bone-conducted sound waves include low to medium frequencies, and the air-conducted sound waves include frequencies within a wider frequency range than the frequencies of the bone-conducted sound waves.

[0025] In some embodiments, the air-conducted sound waves include medium and high frequencies, and the bone-conducted sound waves include frequencies within a wider frequency range than the frequencies of the air-conducted sound waves.

[0026] In some embodiments, the bone-conducted sound waves include medium and high frequencies, and the air-conducted sound waves include frequencies within a wider frequency range than the frequencies of the bone-conducted sound waves.

[0027] Some additional features of this specification may be explained in the following description. Some additional features of this specification will be apparent to those skilled in the art through study of the following description and accompanying drawings, or through understanding the production or operation of the embodiments. The features of this specification may be realized and achieved through practice or use of the methods, means, and combinations of various aspects of the specific embodiments described below. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] This specification will be further described by way of exemplary embodiments. These exemplary embodiments will be described in detail with reference to the accompanying drawings. The drawings are not drawn to scale. These embodiments are non-limiting exemplary embodiments, in which like numbers in the various figures represent similar structures, wherein:

[0029] Figure 1 is a schematic diagram illustrating an exemplary acoustic system according to some embodiments of the present specification;

[0030] Figure 2A and 2B is a schematic diagram of an exemplary acoustic output device according to some embodiments of the present specification;

[0031] Figure 3A is a schematic diagram of an exemplary acoustic output device according to some embodiments of the present specification;

[0032] Figure 3B is a schematic diagram of another exemplary acoustic output device according to some embodiments of the present specification;

[0033] Figure 4 is a schematic diagram of a resonant system according to some embodiments of the present specification;

[0034] Figure 5A is a schematic diagram of an exemplary bone conduction speaker according to some embodiments of the present specification;

[0035] Figure 5B is a schematic diagram of an exemplary air conduction speaker according to some embodiments of the present specification;

[0036] Figure 6 is a schematic diagram of an exemplary acoustic output device according to some embodiments of the present specification;

[0037] Figure 7 is a schematic diagram of an exemplary acoustic output device according to some embodiments of the present specification;

[0038] Figure 8 is a schematic diagram of an exemplary acoustic output device according to some embodiments of the present specification;

[0039] Figure 9 and Figure 10 is a schematic diagram of a leakage frequency response curve of an acoustic output device 600 according to some embodiments of this specification;

[0040] Figure 11 is a schematic diagram of an exemplary acoustic output device according to some embodiments of the present specification;

[0041] Figure 12 is a schematic diagram of an exemplary acoustic output device according to some embodiments of the present specification;

[0042] Figure 13 and Figure 14 is a schematic diagram of a leakage frequency response curve of an acoustic output device 1100 according to some embodiments of this specification;

[0043] Figure 15 is a schematic diagram of an exemplary acoustic output device according to some embodiments of the present specification;

[0044] Figure 16 is a schematic diagram of a leakage frequency response curve of an acoustic output device 1500 according to some embodiments of this specification;

[0045] Figure 17-21 is a diagram of a frequency response characteristic curve of an acoustic output device according to some embodiments of this specification; and

[0046] Figure 22 is a schematic diagram of the vibration displacement-spectrum of a bone conduction speaker according to some embodiments of this specification. DETAILED DESCRIPTION

[0047] The following description is intended to enable one of ordinary skill in the art to implement and utilize this specification, and is provided in the context of a specific application scenario and its requirements. It will be apparent to one of ordinary skill in the art that various modifications may be made to the disclosed embodiments, and that the general principles defined herein may be applied to other embodiments and application scenarios without departing from the principles and scope of this specification. Therefore, this specification is not limited to the described embodiments but should be accorded the broadest scope consistent with the claims.

[0048] The terms used in this specification are for the purpose of describing specific example embodiments only and are not restrictive. As used in this specification, the singular forms "a", "an", and "the" may also include plural forms unless the context clearly indicates an exception. It will be further understood that the terms "comprise", "include", and / or "include", "include", "includes", and / or "includes", when used in this specification, specify the presence of the features, integers, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, operations, elements, components and / or combinations thereof.

[0049] It should be understood that the terms "system," "engine," "unit," "module," and / or "block" are methods used to distinguish different components, elements, parts, portions, or assemblies at different levels. However, these terms may be replaced with other expressions if the same purpose can be achieved.

[0050] Generally, the terms "module," "unit," or "block" as used herein refer to logic embodied in hardware or firmware, or a collection of software instructions. The modules, units, or blocks described herein may be implemented as software and / or hardware and may be stored in any type of non-transitory computer-readable medium or other storage device. In some embodiments, software modules / units / blocks may be compiled and linked into an executable program. It should be understood that software modules may be called from other modules / units / blocks or from themselves, and / or may be called in response to detected events or interrupts. Software modules / units / blocks configured to execute on a processing device may be provided on a computer-readable medium, such as a compact disc, digital video disc, flash drive, disk, or any other tangible medium, or as a digital download (and may be stored in a compressed or installable format, requiring installation, decompression, or decryption prior to execution). Such software code may be stored in part or in full on a storage device of an executing device for execution by the processing device. Software instructions may be embedded in firmware, such as an EPROM. It should also be understood that hardware modules / units / blocks may be comprised of connected logic components, such as gates and flip-flops, and / or may comprise programmable elements, such as programmable gate arrays or processors. The modules / units / blocks or processing device functions described herein may be implemented as software modules / units / blocks, but may be represented by hardware or firmware. Generally, the modules / units / blocks described herein refer to logical modules / units / blocks that can be combined with other modules / units / blocks or divided into sub-modules / sub-units / sub-blocks, although they are physically organized or stored. This description may apply to a system, an engine, or a portion thereof.

[0051] It will be understood that, unless the context clearly indicates otherwise, when a unit, engine, module, or block is referred to as being "on," "connected," or "coupled to" another unit, engine, module, or block, it may be directly on, connected, coupled, or in communication with the other unit, engine, module, or block, or there may be intervening units, engines, modules, or blocks. In this specification, the term "and / or" may include any one or more of the relevant listed items or any combination thereof.

[0052] To more clearly illustrate the technical solutions of the embodiments of this specification, the following briefly describes the drawings required for describing the embodiments. Obviously, the drawings described below are merely examples or embodiments of this specification. Those skilled in the art will be able to apply this specification to other similar scenarios based on these drawings without inventive effort. Unless otherwise apparent from the context or otherwise noted, the same reference numerals in the figures represent the same structures and operations.

[0053] The technical solutions of the embodiments of this specification are described below in conjunction with the accompanying drawings. Obviously, the described embodiments are not exhaustive or restrictive. Based on the embodiments proposed in this specification, other embodiments obtained by ordinary technicians in this field without making any creative efforts are all within the scope of this specification.

[0054] One aspect of this specification relates to an acoustic output device. The acoustic output device may include a bone conduction speaker (also known as a vibration speaker), an air conduction speaker, and at least one housing configured to house the bone conduction speaker and the air conduction speaker. The air conduction speaker is independent of the bone conduction speaker. Various spatial arrangements and / or frequency distributions of the bone conduction speaker and the air conduction speaker may be provided to enhance the audio experience of a user of the acoustic output device at low frequencies and to reduce sound leakage from the acoustic output device.

[0055] Figure 1 1 is a schematic diagram of an exemplary acoustic system according to some embodiments of the present specification. The acoustic system 100 may include a multimedia platform 110 , a network 120 , an acoustic output device 130 , a terminal device 140 , and a storage device 150 .

[0056] The multimedia platform 110 can communicate with one or more components of the acoustic system 100 or an external data source (e.g., a cloud data center). In some embodiments, the multimedia platform 110 can provide data or signals (e.g., audio data of a piece of music) to the acoustic output device 130 and / or the user terminal 140. In some embodiments, the multimedia platform 110 can facilitate data / signal processing for the acoustic output device 130 and / or the user terminal 140. In some embodiments, the multimedia platform 110 can be implemented on a single server or a group of servers. The server group can be a centralized server group connected to the network 120 via an access point, or a distributed server group each connected to the network 120 via one or more access points. In some embodiments, the multimedia platform 110 can be connected to the network 120 locally or remotely. For example, the multimedia platform 110 can access information and / or data stored in the acoustic output device 130, the user terminal 140, and / or the storage device 150 via the network 120. For another example, the storage device 150 can serve as backend data storage for the multimedia platform 110. In some embodiments, the multimedia platform 110 can be implemented on a cloud platform. By way of example only, the cloud platform may include a private cloud, a public cloud, a hybrid cloud, a community cloud, a distributed cloud, an on-premises cloud, a multi-tier cloud, the like, or any combination thereof.

[0057] In some embodiments, multimedia platform 110 may include a processing device 112. Processing device 112 may perform the primary functions of multimedia platform 110. For example, processing device 112 may retrieve audio data from storage device 150 and transmit the retrieved audio data to acoustic output device 130 and / or user terminal 140 to generate sound. For another example, processing device 112 may process signals for acoustic output device 130 (e.g., to generate bone conduction control signals).

[0058] In some embodiments, the processing device 112 may include one or more processing units (e.g., a single-core processing device or a multi-core processing device). By way of example only, the processing device 112 may include a central processing unit (CPU), an application-specific integrated circuit (ASIC), an application-specific instruction set processor (ASIP), a graphics processing unit (GPU), a physical processing unit (PPU), a digital signal processor (DSP), a field programmable gate array (FPGA), a programmable logic device (PLD), a controller, a microcontroller unit, a reduced instruction set computer (RISC), a microprocessor, the like, or any combination thereof.

[0059] Network 120 can facilitate the exchange of information and / or data. In some embodiments, one or more components of acoustic system 100 (e.g., multimedia platform 110, acoustic output device 130, user terminal 140, storage device 150) can transmit information and / or data to other components of acoustic system 100 via network 120. In some embodiments, network 120 can be any type of wired or wireless network, or a combination thereof. By way of example only, network 120 can include a cable network, a wired network, a fiber optic network, a telecommunications network, an intranet, the Internet, a local area network (LAN), a wide area network (WAN), a wireless local area network (WLAN), a metropolitan area network (MAN), a wide area network (WAN), a public switched telephone network (PSTN), a Bluetooth network, a ZigBee network, a near field communication (NFC) network, or the like, or any combination thereof. In some embodiments, network 120 can include one or more network access points. For example, the network 120 may include wired or wireless network access points, such as base stations and / or Internet exchange points, through which one or more components of the acoustic system 100 may connect to the network 120 to exchange data and / or information.

[0060] The acoustic output device 130 can output sound to the user and interact with the user. In one aspect, the acoustic output device 130 can provide the user with at least audio content, such as songs, poems, news broadcasts, weather broadcasts, audio lessons, and the like. In another aspect, the user can provide feedback to the acoustic output device 130, such as keystrokes, screen touches, body movements, voice, gestures, thoughts, and the like. In some embodiments, the acoustic output device 130 can be a wearable device. Unless otherwise specified, wearable devices as used herein may include headphones and various other types of personal devices, such as head-mounted, shoulder-mounted, or body-mounted devices. Wearable devices can present at least audio content to the user with or without contact with the user. In some embodiments, wearable devices may include smart headphones, smart glasses, head-mounted displays (HMDs), smart bracelets, smart shoes, smart glasses, smart helmets, smart watches, smart clothing, smart backpacks, smart accessories, virtual reality helmets, virtual reality glasses, virtual reality patches, augmented reality helmets, augmented reality glasses, augmented reality patches, and the like, or any combination thereof. By way of example only, a wearable device may be like Google Glass. TM 、Oculus Rift TM 、Hololens TM 、GearVR TM ,wait.

[0061] The acoustic output device 130 can communicate with the user terminal 140 via the network 120. In some embodiments, various types of data and / or information, including, for example, motion parameters (e.g., geographic location, movement direction, movement speed, acceleration, etc.), voice parameters (voice volume, voice content, etc.), gestures (e.g., handshakes, head shakes, etc.), user's thoughts, etc., can be received by the acoustic output device 130. In some embodiments, the acoustic output device 130 can further transmit the received data and / or information to the multimedia platform 110 or the user terminal 140.

[0062] In some embodiments, user terminal 140 can be customized, for example, by having an application installed therein to communicate with acoustic output device 130 and / or perform data / signal processing. User terminal 140 may include a mobile device 130-1, a tablet computer 130-2, a laptop computer 130-3, a built-in device 130-4 in a vehicle, or any combination thereof. In some embodiments, mobile device 130-1 may include a smart home device, a smart mobile device, or similar device, or any combination thereof. In some embodiments, smart home devices may include smart lighting devices, smart appliance control devices, smart monitoring devices, smart televisions, smart cameras, intercoms, or any combination thereof. In some embodiments, smart mobile devices may include smartphones, personal digital assistants (PDAs), gaming devices, navigation devices, point-of-sale (POS), or any combination thereof. In some embodiments, built-in device 130-4 in a vehicle may include a built-in computer, a built-in in-vehicle television, a built-in tablet computer, or the like. In some embodiments, user terminal 140 may include a signal transmitter and a signal receiver configured to communicate with a positioning device (not shown) to locate the user and / or user terminal 140. In some embodiments, the multimedia platform 110 or the storage device 150 may be integrated into the user terminal 140. In this case, the functions that can be implemented by the multimedia platform 110 described above may be similarly implemented by the user terminal 140.

[0063] The storage device 150 can store data and / or instructions. In some embodiments, the storage device 150 can store data obtained from the multimedia platform 110, the acoustic output device 130, and / or the user terminal 140. In some embodiments, the storage device 150 can store data and / or instructions that enable various functions of the multimedia platform 110, the acoustic output device 130, and / or the user terminal 140. In some embodiments, the storage device 150 can include mass storage, removable storage, volatile read-write memory, read-only memory (ROM), or any combination thereof. Example mass storage can include magnetic disks, optical disks, solid-state drives, etc. Example removable storage can include flash drives, floppy disks, optical disks, memory cards, compact disks, magnetic tapes, etc. Example volatile read-write memory can include random access memory (RAM). Example RAM can include dynamic random access memory (DRAM), double data rate synchronous dynamic random access memory (DDRSDRAM), static random access memory (SRAM), thyristor random access memory (T-RAM), and zero-capacitance random access memory (Z-RAM). Exemplary ROMs may include mask ROM (MROM), programmable ROM (PROM), erasable programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), compact disc ROM (CD-ROM), and digital versatile disk ROM, among others. In some embodiments, the storage device 150 may be implemented on a cloud platform. By way of example only, the cloud platform may include a private cloud, a public cloud, a hybrid cloud, a community cloud, a distributed cloud, an internal cloud, a multi-layer cloud, or the like, or any combination thereof. In some embodiments, one or more components in the acoustic system 100 may access data or instructions stored in the storage device 150 via the network 120. In some embodiments, the storage device 150 may be directly connected to the multimedia platform 110 as backend storage.

[0064] In some embodiments, the multimedia platform 110, the terminal device 140, and / or the storage device 150 may be integrated into the acoustic output device 130. Specifically, as technology advances and the processing capabilities of the acoustic output device 130 increase, all processing can be performed by the acoustic output device 130. For example, the acoustic output device 130 may be a smart headset, an MP3 player, a hearing aid, etc., which has highly integrated electronic components, such as a central processing unit (CPU) and a graphics processing unit (GPU), and thus has powerful processing capabilities.

[0065] Figure 2A and 2B is a schematic diagram of an exemplary acoustic output device according to some embodiments of the present specification. Figure 2A An oblique view of the acoustic output device 130 is shown. Figure 2BAn exploded view of the acoustic output device 130 is shown. Figure 2A and 2B The acoustic output device 130 will be described.

[0066] In some embodiments, the acoustic output device 130 may include an ear hook 10, an earphone core housing 20, a circuit housing 30, a rear hook 40, an earphone core 50, a control circuit 60, and a battery 70. The earphone core housing 20 and the circuit housing 30 may be respectively disposed at both ends of the ear hook 10, and the rear hook 40 may be further disposed at an end of the circuit housing 30 away from the ear hook 10. The earphone core housing 20 may be used to accommodate different earphone cores 50. The circuit housing 30 may be used to accommodate the control circuit 60 and the battery 70. Both ends of the rear hook 40 may be connected to corresponding circuit housings 30, respectively. The ear hook 10 may refer to a structure configured to hang the acoustic output device 130 on the user's ear and to fix the earphone core housing 20 and the earphone core 50 at a predetermined position relative to the user's ear when the user wears the acoustic output device 130.

[0067] In some embodiments, the ear hook 10 may include an elastic metal wire. The elastic metal wire may be configured to maintain the ear hook 10 in a shape that matches the user's ear and has a certain degree of elasticity. Therefore, when the user wears the acoustic output device 130, it may undergo a certain degree of elastic deformation according to the user's ear and head shape, thereby adapting to users with different ear and head shapes. In some embodiments, the elastic metal wire may be made of a memory alloy with good deformation recovery capabilities. Even if the ear hook 10 is deformed by external force, it may return to its original shape when the external force is removed, thereby extending the life of the acoustic output device 130. In some embodiments, the elastic wire may also be made of a non-memory alloy. Leads may be provided in the elastic metal wire to establish an electrical connection between the earphone core 50 and other components such as the control circuit 60 and the battery 70, thereby facilitating power supply and data transmission of the earphone core 50. In some embodiments, the ear hook 10 may further include a protective cover 16 and a shell protective member 17 integrally formed with the protective cover 16.

[0068] In some embodiments, the earphone core housing 20 can be configured to accommodate the earphone core 50. The earphone core 50 may include one or more speakers. The one or more speakers may include bone conduction speakers, air conduction speakers, etc. The bone conduction speaker can be configured to output sound waves conducted through a solid medium (e.g., bone). For example, a bone conduction speaker can convert an electrical signal into vibrations in the user's skull by direct contact with the user. The air conduction speaker can be configured to output sound waves conducted through the air. For example, an air conduction speaker can convert another electrical signal into air vibrations detectable by the user's ear. The number of earphone cores 50 and earphone core housings 20 can be two, which can correspond to the left and right ears of the user, respectively. Detailed information about the earphone core 50 can be found elsewhere in this specification, for example Figure 3A 、 Figure 3B 、 Figure 4 、 Figure 5A 、 Figure 5B and Figure 6-15 .

[0069] In some embodiments, the ear hook 10 and the earphone core housing 20 can be molded separately and further assembled instead of directly molding the two together.

[0070] In some embodiments, the earphone core housing 20 may provide a contact surface 21. The contact surface 21 may be in contact with the user's skin. During operation of the acoustic output device 130, bone conduction sound waves generated by one or more bone conduction speakers of the earphone core 50 may be transmitted to the outside of the earphone core housing 20 (for example, to the user's eardrum) through the contact surface. In some embodiments, the material and thickness of the contact surface 21 may affect the propagation of bone conduction sound waves to the user, thereby affecting the sound quality. For example, if the material of the contact surface 21 is relatively soft, the propagation of bone conduction sound waves in the low frequency range may be better than the propagation of bone conduction sound waves in the high frequency range. On the contrary, if the material of the contact surface 21 is relatively hard, the propagation of bone conduction sound waves in the high frequency range may be better than the propagation of bone conduction sound waves in the low frequency range.

[0071] Figure 3A is a schematic diagram of an exemplary acoustic output device according to some embodiments of the present specification. Figure 3A As shown, the acoustic output device 300 may include a signal processing module 310 and an output module 320. The signal processing module 310 may receive an electrical signal from a signal source and process the electrical signal. In some embodiments, the electrical signal may be an analog signal or a digital signal. For example, the electrical signal may be a digital signal obtained from the multimedia platform 110, the terminal device 140, the storage device 150, etc.

[0072] The signal processing module 310 can process the electrical signal. For example, the signal processing module 310 can process the electrical signal by performing various signal processing operations (e.g., sampling, digitization, compression, frequency division, frequency modulation, encoding, or the like or a combination thereof). The signal processing module 310 can further generate a control signal based on the processed electrical signal.

[0073] Output module 320 can generate and output bone-conducted sound waves (also referred to as bone-conducted sound) and / or air-conducted sound waves (also referred to as air-conducted sound). Output module 320 can receive control signals from signal processing module 310 and generate bone-conducted sound waves and / or air-conducted sound waves based on the control signals. As described herein, bone-conducted sound waves refer to sound waves that are mechanically transmitted through a solid medium (e.g., bone). Air-conducted sound waves refer to sound waves that are mechanically transmitted through air.

[0074] For illustrative purposes, the output module 320 may include a bone conduction speaker (also known as a vibration speaker) 321 and an air conduction speaker 322. The bone conduction speaker 321 and the air conduction speaker 322 may be electrically coupled to the signal processing module 310. The bone conduction speaker 321 may generate bone-conducted sound waves within a specific frequency range (e.g., low frequency range, mid-frequency range, high frequency range, high-mid frequency range, low-mid frequency range, and high-mid frequency range) in response to a control signal generated by the signal processing module 310. The air conduction speaker 322 may generate air-conducted sound waves within the same or a different frequency range as the bone conduction speaker 321 in response to a control signal generated by the signal processing module 310. In some embodiments, the bone conduction speaker 321 and the air conduction speaker 322 may be two independent functional devices, or two independent components of a single device. As described herein, a first device being independent of a second device means that the operation of the first / second device is not caused by the operation of the second / first device, or in other words, the operation of the first / second device is not the result of the operation of the second / first device. Taking bone conduction speakers and air conduction speakers as an example, air conduction speakers are independent of bone conduction speakers because each of the two speakers is independently driven by an electrical signal to produce sound waves.

[0075] Different frequency ranges can be determined based on actual needs. For example, the low frequency range (also referred to as low frequency) can refer to the frequency range from 20 Hz to 150 Hz, the mid-frequency range (also referred to as mid-frequency) can refer to the frequency range from 150 Hz to 5 kHz, the high-frequency range (also referred to as high frequency) can refer to the frequency range from 5 kHz to 20 kHz, the mid-low frequency range (also referred to as mid-low frequency) can refer to the frequency range from 150 Hz to 500 Hz, and the mid-high frequency range (also referred to as mid-high frequency) can refer to the frequency range from 500 Hz to 5 kHz. For another example, the low frequency range can refer to the frequency range from 20 Hz to 300 Hz, the mid-frequency range can refer to the frequency range from 300 Hz to 3 kHz, the high-frequency range can refer to the frequency range from 3 kHz to 20 kHz, the mid-low frequency range can refer to the frequency range from 100 Hz to 1000 Hz, and the mid-high frequency range can refer to the frequency range from 1000 Hz to 10 kHz. It should be noted that the frequency range values ​​are for illustrative purposes only and are not limiting. The definitions of the above frequency ranges can vary depending on different application scenarios and classification standards. For example, in some other application scenarios, the low frequency range may refer to a frequency range from 20 Hz to 80 Hz, the medium frequency range may refer to a frequency range from 160 Hz to 1280 Hz, the high frequency range may refer to a frequency range from 2560 Hz to 20 kHz, the mid-low frequency range may refer to a frequency range from 80 Hz to 160 Hz, and the mid-high frequency range may refer to a frequency range from 1280 Hz to 2560 Hz. Optionally, different frequency ranges may or may not have overlapping frequencies.

[0076] Figure 3B is a schematic diagram of another exemplary acoustic output device according to some embodiments of the present specification. In some embodiments, as Figure 3B The acoustic output device 305 shown can be used with Figure 3AThe acoustic output device 305 is similar or identical to the illustrated acoustic output device 300, but the acoustic output device 305 may further include a bone conduction signal processing circuit 316 and an air conduction signal processing circuit 317. The bone conduction signal processing circuit 316 may be configured to process bone conduction signals. The air conduction signal processing circuit 317 may be configured to process air conduction signals. In some embodiments, the electrical signal may include a bone conduction signal and an air conduction signal. As described herein, a bone conduction signal refers to an electrical signal associated with bone-conducted sound waves and / or an electrical signal that affects the generation and output of bone-conducted sound waves. An air conduction signal refers to an electrical signal associated with air-conducted sound waves and / or an electrical signal that affects the generation and output of air-conducted sound waves. In some embodiments, the bone conduction signal processing circuit 316 may receive a bone conduction signal from a signal source, process the bone conduction signal, and generate a corresponding bone conduction control signal. A bone conduction control signal refers to a signal that controls the generation and output of bone-conducted sound waves. Similarly, the air conduction signal processing circuit 317 may receive an air conduction signal from a signal source, process the air conduction signal, and generate a corresponding air conduction control signal. The air conduction control signal refers to a signal that controls the generation and output of air conduction sound waves.

[0077] The output module 325 may further include a bone conduction speaker 326 and an air conduction speaker 327. The bone conduction speaker 326 and the air conduction speaker 327 may be respectively Figure 3A The bone conduction speaker 321 and air conduction speaker 322 of the output module 320 are identical or similar and are not repeated here. The bone conduction speaker 326 may be electrically coupled to the bone conduction signal processing circuit 316. The bone conduction speaker 326 may generate and output bone conduction sound waves within a specific frequency range based on a bone conduction control signal generated by the bone conduction signal processing circuit 316. The air conduction speaker 327 may be electrically coupled to the air conduction signal processing circuit 317. The bone conduction speaker 327 may generate and output air conduction sound waves within the same or different frequency range as the bone conduction speaker 326 based on an air conduction control signal generated by the air conduction signal processing circuit 317.

[0078] In some embodiments, the bone conduction signal processing circuit 316 can be integrated with or disposed in the same housing as the bone conduction speaker 326. Similarly, the air conduction signal processing circuit 317 can be integrated with or disposed in the same housing as the air conduction speaker 327.

[0079] Combine Figure 3A and Figure 3BIn order to adjust the output characteristics (e.g., frequency, phase, amplitude, etc.) of the bone conduction sound waves and / or air conduction sound waves, the bone conduction control signal and / or the air conduction control signal can be further processed in the signal processing module 310 or 315 so that the bone conduction sound waves and / or the air conduction sound waves can have different output characteristics. For example, the bone conduction control signal and / or the air conduction control signal can include a specific frequency. In some alternative embodiments, the structure of each component and / or the configuration of at least one component in the output module 320 or 325 can be modified or optimized so that the output characteristics (e.g., frequency) of the bone conduction sound waves and / or the air conduction sound waves can be adjusted.

[0080] In some embodiments, one or more filters or filter groups may be provided to process the bone conduction control signal and / or the air conduction control signal in the signal processing module 310 or 315 to adjust the output characteristics (e.g., frequency) of the bone conduction sound waves and / or the air conduction sound waves. Exemplary filters or filter groups may include, but are not limited to, analog filters, digital filters, passive filters, active filters, etc., or a combination thereof.

[0081] In some embodiments, a time domain processing method may be provided to enrich the acoustic effect of the sound output by the output module 320 or 325. Exemplary time domain processing methods may include dynamic range control (DRC), time delay, and reverberation, among others.

[0082] In some embodiments, the acoustic output device 300 or 305 may also include an active leakage reduction module. In some embodiments, the active leakage reduction module can directly output sound waves without feedback from a reference (e.g., a microphone) to superimpose and cancel leaking sound waves (i.e., sound leakage) from the acoustic output device 300 or 350. The sound waves output from the active leakage reduction module can have the same amplitude, frequency, and opposite phase as the leaking sound waves. In some alternative embodiments, the active leakage reduction module can output sound waves based on feedback from a reference. For example, a microphone can be placed in the sound field of the acoustic output device 300 or 350 to obtain sound field information (e.g., position, frequency, phase, amplitude, etc.) and provide real-time feedback to the active leakage reduction module to dynamically adjust the output sound waves to reduce or eliminate sound leakage from the acoustic output device 300 or 350. In some embodiments, the active leakage reduction module can be incorporated into the output module 320 or 325.

[0083] In some embodiments, the acoustic output device 300 or 305 may further include a beamforming module. The beamforming module may be configured to form a specific beam of bone-conducted sound waves and / or air-conducted sound waves. In some embodiments, the beamforming module may form a specific beam by controlling the amplitude and / or phase of the bone-conducted sound waves and / or air-conducted sound waves transmitted from the output module 320 (e.g., the bone-conducted speaker 321 and the air-conducted speaker 322) or the output module 325 (e.g., the bone-conducted speaker 326 and the air-conducted speaker 327). The beam may, for example, be a fan-shaped beam with a certain angle. The beam may propagate in a specific direction to achieve a maximum sound pressure level near the human ear. At the same time, the sound pressure level at other locations in the sound field may be relatively low, thereby reducing sound leakage from the acoustic output device 300 or 350. In some embodiments, the acoustic output device 300 or 350 may use 3D sound field reconstruction technology or local sound field control technology to produce a more ideal three-dimensional sound field, so that the user can have a more immersive experience in the sound field. In some embodiments, the beamforming module may also be incorporated into the output module 320 or 325 .

[0084] Figure 4 is a schematic diagram of a resonant system according to some embodiments of the present specification. In some embodiments, the effect of the structure and / or configuration of one or more components of the acoustic output device 130 on the characteristics of the acoustic sound output by the acoustic output device 130 can be modeled using a resonant system 400. In some embodiments, the resonant system 400 can be described in conjunction with a mass-spring-damper system. In some embodiments, the resonant system 400 can be described in conjunction with at least two mass-spring-damper systems connected in parallel or in series. The motion of the resonant system 400 can be expressed in formula (1):

[0085] , (1)

[0086] in M represents the mass of the resonant system 400, R represents the damping of the resonant system 400, k represents the elastic coefficient of the resonant system 400, F Indicates driving force, represents the displacement of the resonant system 400 .

[0087] In some embodiments, the resonant frequency of the resonant system 400 can be obtained by solving formula (1). The resonant frequency of the resonant system 400 can be obtained according to formula (2):

[0088] , (2)

[0089] represents the resonant frequency of the resonant system 400 .

[0090] In some embodiments, the frequency bandwidth can be determined based on the half-power point. The quality factor Q of the resonant system 400 can be determined based on formula (3):

[0091] (3)

[0092] In the case of at least two resonant systems, the vibration characteristics (e.g., amplitude-frequency response, phase-frequency response, transient response, etc.) of each of the at least two resonant systems may be the same or different. For example, each of the at least two resonant systems may be driven by the same driving force or different driving forces.

[0093] In some embodiments, the bone conduction speaker 321, the air conduction speaker 322, the bone conduction speaker 326, or the air conduction speaker 327 can be a single resonant system or a combination of at least two resonant systems. In some embodiments, the output module 320 or 325 can also include at least two bone conduction speakers and / or at least two air conduction speakers.

[0094] For bone-conducted sound waves, the frequency and bandwidth of bone-conducted sound waves can be adjusted by modifying the parameters described in the above examples (e.g., mass, damping, etc.). For example, the resonant frequency can be adjusted by increasing the mass, thereby reducing the spring constant (e.g., using a spring with a lower spring constant, using a material with a lower Young's modulus for the vibration transmission structure, reducing the thickness of the vibration transmission structure, etc.). In this case, the resonant system 400 (e.g., a bone conduction speaker) can output vibrations within the low- to mid-frequency range. For another example, the resonant frequency can be adjusted to the high- to mid-frequency range by reducing the mass of the resonant system 400 and increasing its spring constant (e.g., using a spring with a higher spring constant, using a material with a higher Young's modulus for the vibration transmission structure, increasing the thickness of the vibration transmission structure, or providing reinforcing ribs or other reinforcement structures on the vibration transmission structure). In this case, the resonant system 400 can output vibrations within the high- to mid-frequency range. For another example, the bandwidth of the vibration output of the resonant system 400 can be adjusted by changing the quality factor (Q). For another example, a composite resonant system can be provided, comprising at least two resonant systems. The resonant frequency and quality factor (Q) of each resonant system can be adjusted independently. The center frequency and bandwidth of the composite resonant system can be adjusted by connecting at least two resonant systems in series or in parallel.

[0095] For air-conducted sound waves, the frequency and bandwidth of air-conducted sound waves can be similarly adjusted by varying the parameters exemplified above (e.g., mass, damping, etc.). In some embodiments, one or more acoustic structures may be provided to adjust the frequency of air-conducted sound waves. The one or more acoustic structures may include, for example, an acoustic cavity, an acoustic tube, an acoustic hole, a pressure relief vent, a tuning mesh, a tuning foam, a passive diaphragm, or a combination thereof. For example, the elastic modulus of system 400 can be adjusted by varying the volume of the acoustic cavity. If the volume of the acoustic cavity is increased, the elastic modulus of the system can be reduced. If the volume of the acoustic cavity is decreased, the elastic modulus of the system can be increased. In some embodiments, the mass and damping of system 400 can be adjusted by providing an acoustic tube or an acoustic hole. A longer acoustic tube or an acoustic hole has a smaller cross-section, a higher mass, and lower damping. Conversely, a shorter acoustic tube or an acoustic hole has a larger cross-section, a lower mass, and higher damping. In some embodiments, the damping of system 400 can be adjusted by providing acoustically resistive materials (e.g., tuning holes, a tuning mesh, a tuning foam, etc.) along the propagation path of the air-conducted sound waves. In some embodiments, a passive diaphragm can be provided to enhance air-conducted sound waves in the low-frequency range. In some embodiments, the phase, amplitude, and / or frequency range of the air-conducted sound waves can be adjusted by providing one or more acoustic tubes and / or inverting holes. In other embodiments, a series of air-conducted speakers can be provided. The amplitude, frequency range, and phase of each air-conducted speaker can be adjusted to form a sound field with a specific spatial distribution.

[0096] In some embodiments, the output characteristics of the bone-conducted sound waves and / or the air-conducted sound waves can also be adjusted by the user (for example, by setting the amplitude, frequency, and / or phase of the control signal). In some embodiments, the output characteristics of the bone-conducted sound waves and / or the air-conducted sound waves can also be adjusted by parameters of the resonance system 400 and the control signal set by the user.

[0097] Figure 5AFigure 5 is a schematic diagram of an exemplary bone conduction speaker according to some embodiments of this specification. Bone conduction speaker 500 may include a vibration assembly 510. Vibration assembly 510 may include or be housed in a housing 520. Vibration assembly 510 may be electrically connected to signal processing module 310 or 315 to receive bone conduction control signals and generate bone conduction sound waves based on the bone conduction control signals. For example, vibration assembly 510 may be or include any element (e.g., a vibration motor, an electromagnetic vibration device, etc.) that converts an electrical signal (e.g., a bone conduction control signal) into a mechanical vibration signal. Exemplary signal conversion methods include, but are not limited to, electromagnetic (e.g., moving coil, moving iron, magnetostrictive), piezoelectric, and electrostatic. The internal structure of vibration assembly 510 may be a single resonant system or a composite resonant system. In some embodiments, vibration assembly 510 may generate mechanical vibrations based on the bone conduction control signals. Mechanical vibrations may generate bone conduction sound waves.

[0098] like Figure 5A As shown, the vibration assembly 510 may include a magnetic circuit system 511, a vibration plate 512, and one or more coils 513. The magnetic circuit system 511 may be configured to generate a magnetic field. In some embodiments, the magnetic circuit system 511 may include a magnetic gap. The magnetic circuit system 511 may generate a magnetic field within the magnetic gap. The vibration plate 512 may contact the user's skin (e.g., the skin on the user's head) and transmit bone-conducted sound waves to the user's cochlea when the user wears the acoustic output device 300 or 305. The vibration plate 512 may also be referred to as the bottom wall of the housing 520. As used herein, the "bottom" or "top" portion of an assembly is described relative to the user's skin. For example, in the housing 520, the wall closest to the user's skin (e.g., the wall attached to the skin) is referred to as the bottom wall or rear wall, while the wall farthest from the user's skin (e.g., the wall opposite the top wall) is referred to as the top wall or front wall. The one or more coils 513 may be mechanically connected to the vibration plate 512. In some embodiments, one or more coils 513 may also be electrically connected to the signal processing module 310 or 315. In some embodiments, one or more coils 513 may be placed in a magnetic gap. When current is introduced into one or more coils 513, one or more coils 513 may vibrate in the magnetic field and drive the vibration plate 512 to vibrate, thereby generating bone conduction sound waves.

[0099] Figure 5Bis a schematic diagram of an exemplary air conduction speaker according to some embodiments of the present specification. In some embodiments, the air conduction speaker 550 can be a general-purpose speaker that generates sound waves that propagate through the air. In some embodiments, the air conduction speaker 550 can be a specially designed speaker that is customized to meet certain requirements (e.g., requirements for output characteristics). In some embodiments, the air conduction speaker 550 can include a diaphragm 551 and a driver 552. The diaphragm 551 can be a thin film made of a material sensitive to variable magnetic fields. Example materials for the diaphragm 551 can include polyarylate (PAR), thermoplastic elastomer (TPE), polytetrafluoroethylene (PTFE), etc. The driver 552 can be a moving iron driver, a dynamic coil driver, etc., or a combination thereof. In some embodiments, the driver 552 can receive an air conduction control signal from the signal processing module 310 or 315 (e.g., the air conduction signal processing circuit 317) and drive the diaphragm 551 to vibrate according to the air conduction control signal, thereby generating air conduction sound waves.

[0100] In some embodiments, an air conduction speaker 550 including a diaphragm 551 and a driver 552 may be housed in a housing 560. In some embodiments, the diaphragm 551 may have a large size so that the cavity of the housing 560 may be divided into two parts including a front part 561 and a rear part 562 by the diaphragm 551. The front part 561 refers to the part on the front side of the diaphragm 521 (e.g., Figure 5B The rear portion 562 refers to the portion on the rear side of the diaphragm 521 (e.g., Figure 5B The upper part shown) can be called the "back cavity".

[0101] In some embodiments, at least one acoustic hole (e.g., acoustic hole 570) may be provided on the wall of the front cavity of the housing 560. The acoustic hole may be a through hole. Air-conducted sound waves generated in the front cavity of the housing 560 may propagate outside the housing 560 through the at least one acoustic hole. In some embodiments, when the user wears the acoustic output device 300 or 305, the acoustic hole may face the user's external auditory canal.

[0102] In some embodiments, a sound tube (not shown) may be coupled to a sound hole. In some embodiments, air-conducted sound waves passing through the sound hole may enter the sound tube and propagate in a specific direction through the sound tube. In this way, the sound tube may change the direction of propagation of the air-conducted sound waves.

[0103] In some embodiments, a pressure relief hole (not shown) may be provided on the wall of the rear cavity of the housing 560. The pressure relief hole may be a through hole that facilitates pressure balance between the rear cavity of the housing 560 and the outside. In addition, the pressure relief hole may help adjust the frequency response of the air conduction speaker 550 at low frequencies.

[0104] In some embodiments, air-conducted sound waves can be transferred to the outside through the pressure relief holes, resulting in sound leakage. In some embodiments, specially designed pressure relief holes can reduce or suppress sound leakage. For example, the pressure relief holes can be larger so that the resonant peak (Helmholtz resonance) of the rear cavity of the housing 560 corresponds to a higher frequency. This can suppress the leakage of mid- and low-frequency sound propagating through the pressure relief holes. Furthermore, a larger pressure relief hole can reduce the acoustic impedance and the sound pressure of the sound waves at the pressure relief hole, thereby reducing sound leakage.

[0105] In some further embodiments, a tuning mesh (not shown) may be provided at the pressure relief hole to reduce the intensity of the resonance peak, thereby reducing the frequency response of the rear cavity of the housing 520 and suppressing sound leakage.

[0106] In some embodiments, the output characteristics of bone-conducted sound waves can be adjusted by changing the stiffness of the vibration plate 512 and / or the shell 520 (for example, the through dimensions, material elastic modulus, ribs and / or other mechanical structures of the vibration plate 512 and / or the shell 520). In some embodiments, the output characteristics of air-conducted sound waves can be adjusted by changing the shape, elastic coefficient and damping of the diaphragm 521. In some embodiments, the output characteristics of air-conducted sound waves can also be adjusted by changing the number, position, size and / or shape of at least one sound hole and / or pressure relief hole. For example, the sound hole 570 can be provided with a damping structure (for example, a tuning mesh) to adjust the acoustic effect of the air-conducting speaker 550.

[0107] It should be noted that the number, size, shape (e.g., cross-sectional shape), and / or location of one or more additional acoustic structures (e.g., sound holes, sound tubes, pressure relief holes, and / or tuning mesh) exemplified above can be configured based on practical needs and are not intended to be limiting in this specification. In some embodiments, the number, size, shape, and / or location of one or more additional acoustic structures can be optimized based on sound leakage from the acoustic output device 500. In some embodiments, optimization can be performed based on the leakage frequency response curve provided below. Furthermore, the spatial arrangement of the bone conduction speaker 500 and the air conduction speaker 550, and / or one or more of the bone conduction speaker 500 and the air conduction speaker 550, is not intended to be limiting in this specification. For example, the spatial arrangement of the bone conduction speaker 500 and the air conduction speaker 550 (e.g., the air conduction speaker 550 can be arranged side by side with the bone conduction speaker 500, the air conduction speaker 550 and the bone conduction speaker 500 can be stacked, etc.) can vary based on practical needs and is not intended to be limiting. For another example, the position of the driver 552 and / or the diaphragm 551 in the housing 560, the direction of the diaphragm 551 (eg, the direction of the front side), etc. may be changed according to actual needs and may not be restricted.

[0108] The acoustic output device provided herein can combine a bone conduction speaker (e.g., bone conduction speaker 500) and an air conduction speaker (e.g., air conduction speaker 550) to provide users with enhanced acoustic effects and tactile sensations. In some embodiments, the bone conduction sound waves and air conduction sound waves output by the acoustic output device can include sound waves of different frequencies.

[0109] Figure 6 is a schematic diagram of an exemplary acoustic output device according to some embodiments of the present specification. Figure 6 As shown, the acoustic output device 600 includes a first housing 610, a second housing 620, a bone conduction speaker 630, and an air conduction speaker 640. The bone conduction speaker 630 can be used with Figure 5A The structure of the bone conduction speaker 630 can be simplified as follows: Figure 6As shown. The bone conduction speaker 630 may be electrically coupled to the bone conduction signal processing circuit 316 and configured to generate bone conduction sound waves based on a bone conduction control signal generated by the bone conduction signal processing circuit 316. The bone conduction speaker 630 may be located inside the bottom wall of the first housing 610. The bone conduction sound waves generated by the bone conduction speaker 630 may be transmitted to the user through the bottom wall of the first housing 610. The bottom wall may be in contact with the user's skin (e.g., represented by dashed line 650). In some embodiments, the vibration plate of the bone conduction speaker 630 may be mechanically connected to the bottom wall of the first housing 610, or the bottom wall of the first housing 610 may be part of the bone conduction speaker 630 and may be considered the vibration plate of the bone conduction speaker 630. In this case, the vibration plate may vibrate in a direction perpendicular or substantially perpendicular to the user's skin (dashed line 650). In some alternative embodiments, the bone conduction speaker 630 may be located on the upper wall of the first housing 610, opposite the bottom wall of the first housing 610. As used in this specification, two directions are considered to be substantially perpendicular to each other if the difference between the angle formed by two directions and 0 degrees (or 180 degrees) is less than a threshold degree (e.g., 2 degrees, 5 degrees, 10 degrees). Similarly, two directions are considered to be substantially perpendicular to each other if the difference between the angle formed by two directions and 90 degrees is less than a threshold degree (e.g., 2 degrees, 5 degrees, 10 degrees).

[0110] The air conduction speaker 640 may be coupled to the air conduction signal processing circuit 317 and configured to generate air conduction sound waves based on the air conduction control signal generated by the air conduction signal processing circuit 317. The air conduction speaker 640 may be disposed next to the bone conduction speaker 630. Specifically, the bone conduction speaker 630 and the air conduction speaker 640 may be disposed along a reference plane (e.g., a plane on which the user's skin or the bottom wall of the first housing 610 lies). The air conduction speaker 640 may be located on one side of the bone conduction speaker 630.

[0111] The bone conduction speaker 630 may be located in the cavity 611 of the first housing 611. The air conduction speaker 640 may be located in the cavity 621 of the second housing 620. The cavity 611 of the first housing 611 and the cavity 621 of the second housing 620 may not be connected to each other. The second housing 620 may also be disposed next to the first housing 610. In some embodiments, the first housing 610 and the second housing 620 may be fixedly connected and connected to each other. For example, the first housing 610 and the second housing 620 may share the same sidewall therebetween. In some embodiments, the first housing 610 and the second housing 620 may be separated (for example, there is a distance between the first housing 610 and the second housing 620) and connected to each other via a connecting assembly.

[0112] The front side of the diaphragm of the air conduction speaker 640 can face any direction. In some embodiments, the front side of the diaphragm of the air conduction speaker 640 can face the bottom wall of the second housing 620 (ie, facing the bottom wall of the second housing 620). Figure 6 The dotted line 650 in the figure is downward. The vibration direction 630 of the bone conduction speaker (i.e., the direction of the bone-conducted sound waves propagating from the bone conduction speaker 630) can be perpendicular or substantially perpendicular to the user's skin, and the central vibration direction of the diaphragm of the air conduction speaker 640 can also be perpendicular or substantially perpendicular to the user's skin. As used herein, the central vibration direction of the diaphragm refers to the vibration direction of the center of the diaphragm of the air conduction speaker 640. The vibration direction of the bone conduction speaker 630 can be the same as the vibration direction of the vibration plate of the bone conduction speaker 630. In this case, the central vibration direction of the diaphragm of the air conduction speaker 640 can be parallel to the vibration direction of the bone conduction speaker 630.

[0113] In some embodiments, at least one sound hole may be provided on a wall of the second housing 620. The at least one sound hole may cause air-conducted sound waves to propagate out of the cavity 621. For example, a first sound hole 622 may be provided on an upper wall of the second housing 620. A second sound hole 623 may be provided on a side wall of the second housing 620. In some embodiments, the second sound hole 623 may be located below a front surface of the air-conducting speaker 640 (e.g., a diaphragm of the air-conducting speaker 640) in a vertical direction perpendicular to the bottom wall of the second housing 620.

[0114] When a user wears the acoustic output device 600, the first housing 610 can be directly or indirectly connected to the user's skin. The bottom wall of the first housing 610, in contact with the user's skin, can transmit bone-conducted sound waves to the user's cochlea through the user's skin and bones. In some embodiments, the air-conduction speaker 640 can be closer to the listening position (e.g., the user's ear) than the bone-conduction speaker 630. The second sound hole 623 in the second housing 620 can be positioned toward the listening position so that the air-conducted sound waves can be transmitted directly to the user's ear, thereby reducing sound loss and increasing the volume of the sound heard by the user.

[0115] It should be noted that at least one sound hole (e.g., sound holes 622 and 623) may be provided for illustrative purposes and not restrictive. In some alternative embodiments, the sound hole 623 may not be required. The front cavity of the second shell 620 may be omitted. The air-conducted sound waves generated by the diaphragm of the air-conducting speaker 640 can propagate directly outside the second shell 620. In this case, the diaphragm of the air-conducting speaker can form a wall (e.g., a bottom wall) of the second shell 620. In some embodiments, one or more additional acoustic structures (e.g., a tuning mesh, a pressure relief hole, a sound tube, etc.) may be provided.

[0116] The bone conduction speaker 630 may be electrically coupled to the bone conduction signal processing circuit 316. The bone conduction speaker 630 may generate and output bone conduction sound waves within a specific frequency range (e.g., a low frequency range, a mid-frequency range, a high frequency range, a mid-low frequency range, a mid-high frequency range, etc.) in response to a bone conduction control signal generated by the bone conduction signal processing circuit 316. The air conduction speaker 640 may be electrically coupled to the air conduction signal processing circuit 317. The air conduction speaker 640 may generate and output air conduction sound waves within the same or a different frequency range as the bone conduction speaker 630 in response to an air conduction control signal generated by the air conduction signal processing circuit 317.

[0117] For example, bone-conducted sound waves can include mid- and high-frequency sound waves, while air-conducted sound waves can include mid- and low-frequency sound waves. The mid- and low-frequency air-conducted sound waves can complement the mid- and high-frequency bone-conducted sound waves. The total output of the acoustic output device can cover both mid- and low-frequency sound waves. This provides better sound quality (especially at low frequencies) and avoids the strong vibrations of the bone-conducted speaker at low frequencies.

[0118] For another example, bone-conducted sound waves may include mid-low frequencies, while air-conducted sound waves may include mid-high frequencies. In this case, the acoustic output device may provide a prompt or warning to the user through a bone-conducted speaker and / or an air-conducted speaker, because the user is sensitive to mid-low frequency bone-conducted sound waves and / or mid-high frequency air-conducted sound waves.

[0119] For another example, air-conducted sound waves may include mid- and low-frequency frequencies, while bone-conducted sound waves may include frequencies in a wider frequency range (wide-range frequency) than air-conducted sound waves. The output of mid- and low-frequency frequencies may be enhanced, and the sound quality may be improved. More details about the frequency distribution of bone-conducted sound waves and / or air-conducted sound waves may be found elsewhere in this specification, for example, Figure 17-21 .

[0120] It should be noted that the above description is provided for illustrative purposes only and is not intended to limit the scope of this specification. For those skilled in the art, various changes and modifications can be made based on the description of this specification. However, these changes and modifications do not depart from the scope of this specification. For example, the relative position of the bone conduction speaker 630 and the air conduction speaker 640, the mass, shape and / or size of the first shell 610 and / or the second shell 620, one or more additional acoustic structures, etc., can be modified and optimized according to various needs and are not limited in this specification.

[0121] Figure 7is a schematic diagram of an exemplary acoustic output device according to some embodiments of the present specification. In some embodiments, acoustic output device 700 can be the same as or similar to acoustic output device 600, except that the front side of the diaphragm of air conduction speaker 740 can be upward relative to the bottom of second housing 720 (i.e., toward the upper wall of second housing 720). When a user wears acoustic output device 700, the bottom wall of first housing 710, which houses bone conduction speaker 730, can come into contact with the user's skin (e.g., represented by horizontal dashed line 750).

[0122] In some embodiments, the sound hole 723 may be provided on the side wall of the second housing 720. The sound hole 723 may be provided above the front surface of the air conduction speaker 740 (e.g., the surface of the diaphragm of the air conduction speaker 740) in a direction perpendicular to the bottom wall of the second housing 720. Figure 7 Not shown) may be provided on the side wall of the second housing 720. The pressure relief hole may be provided below the front surface of the air conduction speaker 740 in a direction perpendicular to the bottom wall of the second housing 720.

[0123] Figure 8 is a schematic diagram of an exemplary acoustic output device according to some embodiments of the present specification. Figure 8 As shown, acoustic output device 800 may include a housing 810, a bone conduction speaker 830, and an air conduction speaker 840. In some embodiments, acoustic output device 800 may be similar to acoustic output device 700, except that bone conduction speaker 830 and air conduction speaker 840 may share the same cavity of housing 810. Bone conduction speaker 830 may be located inside the bottom wall of housing 810. Bone-conducted sound waves generated by bone conduction speaker 830 may be transmitted to the user through the bottom wall of housing 810. The bottom wall of housing 810 may contact the user's skin (e.g., represented by dashed line 850). Air conduction speaker 840 may be located in housing 810 next to bone conduction speaker 830.

[0124] In some embodiments, the housing 810 may define a front cavity together with the front surface of the air conduction speaker 840 (e.g., the surface of the diaphragm of the air conduction speaker 840). The front surface of the air conduction speaker 840 may face upward relative to the bottom wall of the housing 810 and radiate air-conducted sound waves toward the front cavity. In some embodiments, the air conduction speaker 840 may be fixed between the side wall of the housing 810 and a fixed side that protrudes into the cavity of the housing 810. For example, the fixed side may extend in a vertical direction perpendicular to the bottom wall of the housing 810. The combination of the fixed side, the side wall of the housing 810, and the diaphragm of the air conduction speaker 840 may form the front cavity of the air conduction speaker 840.

[0125] In some embodiments, the housing 810 may provide at least one sound hole. For example, the sound hole 822 may be provided on the side wall of the front cavity of the housing 810. In some embodiments, the sound hole 822 may be oriented toward the listening position (e.g., the user's ear when the user wears the acoustic output device 800). The sound hole 822 may be located above the front surface of the air conduction speaker (e.g., the diaphragm surface of the air conduction speaker 840) in a vertical direction perpendicular to the bottom wall of the housing 810. In some alternative embodiments, the front surface of the air conduction speaker 840 (e.g., the diaphragm surface of the air conduction speaker 840) may face downward relative to the bottom of the housing 810. In this case, the position of the sound hole 822 may change accordingly. In some embodiments, the housing 810 may also provide a pressure relief hole 812 for balancing the pressure in the rear cavity of the air conduction speaker 840 defined by the housing 810. As Figure 8 As shown, the bone conduction speaker 830 may be located in the rear cavity of the air conduction speaker 840. The pressure relief hole 812 and the air conduction speaker 840 may be located on opposite sides of the bone conduction speaker 830. The distance between the sound hole 822 and the air conduction speaker 840 may be shorter than the distance between the pressure relief hole 812 and the air conduction speaker 840.

[0126] Figure 9 and Figure 10 is a schematic diagram of a leakage frequency response curve of an acoustic output device 600 according to some embodiments of the present specification. The leakage frequency response curve of the acoustic output device 600 refers to a curve representing how the sound leakage of the acoustic output device 600 changes with the frequency of the sound. For the acoustic output device 600, an air conduction speaker 640 can be provided next to the bone conduction speaker 630. Leakage frequency response curves of the acoustic output device 600 under various conditions can be provided. The horizontal axis can represent the frequency of the sound. The vertical axis can be the amount of sound leakage of the acoustic output device 600. Figure 9 As shown, under the condition that the acoustic output device 600 includes only the bone conduction speaker 630 (the air conduction speaker 640 is omitted), a first leakage frequency response curve 910 is provided. Under the condition that at least one sound hole is provided on the wall of the front cavity of the second housing 620, a second leakage frequency response curve 920 is provided. Under the condition that at least one sound hole on the wall of the front cavity of the second housing 620 is omitted, a third leakage frequency response curve 930 is provided. Figure 10 As shown, under the condition that at least one sound hole is provided on the wall of the rear cavity of the second housing 620, a fourth leakage frequency response curve 1010 is provided. Under the condition that at least one sound hole on the wall of the rear cavity of the second housing 620 is omitted, a fifth leakage frequency response curve 1020 is provided. Under the condition that the mass of the second housing 620 is increased, a sixth leakage frequency response curve 1030 is provided.

[0127] It can be inferred that when the acoustic output device 600 includes only the bone conduction speaker 630 (omitting the air conduction speaker 640), sound leakage at most frequencies is greater than when the acoustic output device 600 includes both the bone conduction speaker 630 and the air conduction speaker 640. Therefore, when the air conduction speaker 640 is positioned next to the bone conduction speaker 630, the combination of the bone conduction speaker 630 and the air conduction speaker 640 can reduce sound leakage. Furthermore, the placement of at least one sound hole in the wall of the front or rear cavity of the housing 620 can have minimal impact on sound leakage from the acoustic output device 600. It can also be inferred that the vibration amplitude of the non-vibrating walls of the first and second housings 610, 620 (e.g., the upper and side walls of the first housing 610) can be reduced by increasing the mass of the acoustic output device 600 and the stiffness of the walls of the first and / or second housings 610, 620. Consequently, sound leakage from the acoustic output device 600 can be effectively reduced within a specific frequency range (e.g., a frequency range greater than 400 Hz).

[0128] Figure 11 is a schematic diagram of an exemplary acoustic output device according to some embodiments of the present specification. Figure 11As shown, the acoustic output device 1100 may include a housing 1110, a bone conduction speaker 1120, and an air conduction speaker 1130. The bone conduction speaker 1120 may be located inside the bottom wall of the housing 1110. Bone-conducted sound waves generated by the bone conduction speaker 1120 may be transmitted to the user through the bottom wall of the housing 1110. The bottom wall may be in contact with the user's skin (e.g., represented by dashed line 1150). In some embodiments, the vibration plate of the bone conduction speaker 1120 may be mechanically connected to the bottom wall of the housing 1110, or the bottom wall of the housing 1110 may be part of the bone conduction speaker 1120 and considered the vibration plate of the bone conduction speaker 1120. In this case, the vibration plate may vibrate in a direction perpendicular or substantially perpendicular to the user's skin (dashed line 1150). In some alternative embodiments, the bone conduction speaker 1120 may be located on the upper wall of the housing 1110, opposite the bottom wall of the housing 1110. The air conduction speaker 1130 and the bone conduction speaker 1120 may be stacked. Specifically, the air conduction speaker 1130 may be located above the bone conduction speaker relative to a reference plane (e.g., the plane where the user's skin or the bottom wall of the housing 1110 is located). The housing 1110 may include a first cavity 1111 and a second cavity 1112, which are arranged along a direction from the upper wall to the bottom wall of the housing 1110. In some embodiments, the first cavity 1111 and the second cavity 1112 may not be connected to each other. For example, the first cavity 1111 and the second cavity 1112 may be separated by a membrane, an inner wall of the housing 1110, or the like. The bone conduction speaker 1120 may be located in the first cavity 1111 of the housing 1110. The air conduction speaker 1130 may be located in the second cavity 1112 of the housing 1110. As Figure 11 As shown, the second cavity 1112 may be the front cavity of the air conduction speaker 1130. Alternatively, if the air conduction speaker 1130 is inverted (ie, turned upside down), the second cavity 1112 may be the rear cavity of the air conduction speaker 1130.

[0129] In some embodiments, the front side of the air conduction speaker 1130 may face the bottom of the housing 1110. The vibration direction of the bone conduction speaker 1120 (i.e., the direction of the bone conduction sound waves 1120 propagating from the bone conduction speaker) may be perpendicular to the user's skin, and the central vibration direction of the diaphragm of the air conduction speaker 1130 may also be perpendicular to the user's skin. In this case, the central vibration direction of the diaphragm of the air conduction speaker 1130 may be the same as the vibration direction of the bone conduction speaker 1120.

[0130] In some embodiments, to reduce sound leakage from the acoustic output device 1100, a pressure relief hole 1113 may be provided on the side wall of the housing 1110. The pressure relief hole 1113 may connect the rear cavity of the air conduction speaker 1130 to the outside, and is also referred to as a rear cavity sound hole. In some embodiments, a sound hole 1114 may be provided on the side wall of the front cavity 1112 of the air conduction speaker 1130. The sound hole 1114 may connect the front cavity 1112 to the outside. In some embodiments, the sound hole 1114 may be located on the front surface of the air conduction speaker 1130 (e.g., the diaphragm surface of the air conduction speaker 1130). The sound hole 1114 may transmit air-conducted sound waves to a listening position (e.g., the user's ear when the user is wearing the acoustic output device 1100).

[0131] In some embodiments, the air conduction speaker 1130 can be closer to the listening position than the bone conduction speaker 1120, and the sound hole 1114 can be oriented toward the listening position, so that air-conducted sound waves can propagate directly to the listening position through the sound hole 1114. In some alternative embodiments, the sound hole 1114 may not be required. The front cavity of the housing 1110 (e.g., the side wall facing the listening position) may be omitted. The air-conducted sound waves generated by the diaphragm of the air conduction speaker 1130 can propagate directly to the exterior of the housing 1110. In this case, the diaphragm of the air conduction speaker can form a wall of the housing 1110.

[0132] The bone conduction speaker 1120 may be electrically coupled to the bone conduction signal processing circuit 316. Bone conduction speaker 1120 may generate and output bone conduction sound waves within a specific frequency range (e.g., a low frequency range, a mid-frequency range, a high frequency range, a mid-low frequency range, a mid-high frequency range, etc.) based on a bone conduction control signal generated by the bone conduction signal processing circuit 316. The air conduction speaker 1130 may be electrically coupled to the air conduction signal processing circuit 317. Air conduction speaker 1130 may generate and output air conduction sound waves within the same or a different frequency range as bone conduction speaker 1120 based on an air conduction control signal generated by the air conduction signal processing circuit 317.

[0133] For example, bone-conducted sound waves can include mid- and high-frequency sound waves, while air-conducted sound waves can include mid- and low-frequency sound waves. The mid- and low-frequency air-conducted sound waves can complement the mid- and high-frequency bone-conducted sound waves. The total output of the acoustic output device can cover both mid- and low-frequency sound waves. This provides better sound quality (especially at low frequencies) and avoids the strong vibrations of the bone-conducted speaker at low frequencies.

[0134] More detailed information on the frequency distribution of bone-conducted sound waves and / or air-conducted sound waves can be found elsewhere in this specification, e.g. Figure 17-21 .

[0135] It should be noted that the above description is provided for illustrative purposes only and is not intended to limit the scope of this specification. For those skilled in the art, various changes and modifications can be made based on the description of this specification. However, these changes and modifications do not depart from the scope of this specification. For example, the relative positions of the bone conduction speaker 1120 and the air conduction speaker 1130, the mass, shape and / or size of the shell 1110, one or more additional acoustic structures, etc., can be modified and optimized according to various needs and are not limited in this specification. For another example, the bone conduction speaker 1120 and the air conduction speaker 1130 can be respectively housed in two shells.

[0136] Figure 12 is a schematic diagram of an exemplary acoustic output device according to some embodiments of the present specification. Figure 12 As shown, acoustic output device 1200 may include a housing 1210, a bone conduction speaker 1220, and an air conduction speaker 1230. In some embodiments, acoustic output device 1200 may be identical or similar to acoustic output device 1100, except that the front side of the diaphragm of air conduction speaker 1230 may face upward relative to the bottom wall of housing 1210 (i.e., toward the upper wall of housing 1210). Bone conduction speaker 1220 may be located inside the bottom wall of housing 1210. Bone-conducted sound waves generated by bone conduction speaker 1120 may be transmitted to the user through the bottom wall of housing 1210. The bottom wall may contact the user's skin (e.g., represented by dashed line 1150). Air conduction speaker 1230 and bone conduction speaker 1220 may be stacked. In some embodiments, air conduction speaker 1230 and bone conduction speaker 1220 may be arranged sequentially along housing 1210, from the upper wall to the bottom wall. Air conduction speaker 1230 and bone conduction speaker 1220 may share the same cavity of housing 1210. In some embodiments, the front face of the air conduction speaker 1230 may face upward relative to the bottom wall of the housing 1210 .

[0137] In some embodiments, the sound hole 1214 may be provided on the side wall of the housing 1210. For example, the sound hole 1214 may be provided on the side wall of the front cavity of the air conduction speaker 1120. In some embodiments, the pressure relief hole 1213 may be provided on the side wall of the housing 1210. For example, the pressure relief hole 1213 may be provided on the side wall of the rear cavity of the air conduction speaker 1120. The bone conduction speaker 1220 may also be located in the rear cavity of the air conduction speaker 1230.

[0138] Figure 13 and Figure 141 is a schematic diagram of a leakage frequency response curve of an acoustic output device 1100 according to some embodiments of the present specification. The air conduction speaker 1130 and the bone conduction speaker 1120 of the acoustic output device 1100 may be stacked. A leakage frequency response curve of the acoustic output device 1100 under various conditions may be provided. The horizontal axis may represent the frequency of the sound. The vertical axis may represent the amount of sound leakage from the acoustic output device 1100. Figure 13 As shown, under the condition that the acoustic output device 1100 includes only the bone conduction speaker 1120 (the air conduction speaker 1130 is omitted), a first leakage frequency response curve 1310 is provided. Under the condition that at least one sound hole is on the wall of the rear cavity of the housing 1110, a second leakage frequency response curve 1320 is provided. Under the condition that at least one sound hole on the wall of the rear cavity of the housing 1110 is omitted, a third leakage frequency response curve 1130 is provided. Figure 14 As shown, a fourth leakage frequency response curve 1410 is provided under the condition that at least one sound hole is provided on the wall of the front cavity of the housing 1110. A fifth leakage frequency response curve 1420 is provided under the condition that at least one sound hole is omitted from the wall of the front cavity of the housing 1110. A sixth leakage frequency response curve 1430 is provided under the condition that the mass of a portion of the housing 1110 is increased.

[0139] It can be inferred that when the acoustic output device 1100 includes only the bone conduction speaker 1120 (omitting the air conduction speaker 1130), sound leakage within specific frequency ranges (e.g., 1000 Hz-3000 Hz and 8000 Hz-10 kHz) is greater than when the acoustic output device 1100 includes both the bone conduction speaker 1120 and the air conduction speaker 1130. Furthermore, the placement of at least one sound hole in the wall of the rear cavity of the housing 1110 can reduce sound leakage from the acoustic output device 1100 within a specific frequency range (e.g., less than 1000 Hz). However, the placement of at least one sound hole in the wall of the front cavity of the housing 1110 can increase sound leakage from the acoustic output device 1100 within a specific frequency range (e.g., 3000 Hz-10 kHz). It can also be inferred that the vibration amplitude of the non-vibrating wall of the housing 1110 can be reduced by increasing the mass of the acoustic output device 1100 and the stiffness of at least one wall of the housing 1110. Therefore, sound leakage of the acoustic output device 1100 within a specific frequency range (eg, a frequency range of 6000-10000 Hz) can be effectively reduced.

[0140] Figure 15 is a schematic diagram of an exemplary acoustic output device according to some embodiments of the present specification. Figure 15As shown, acoustic output device 1500 may include a bone conduction speaker 1520 and an air conduction speaker 1530. Bone conduction speaker 1520 and air conduction speaker 1530 may be housed in the same housing 1510. Bone conduction speaker 1520 may be located inside a bottom wall 1511 of housing 1510. When a user wears acoustic output device 1500, bone conduction sound waves 1520 generated by the bone conduction speaker are transferred to the user via the bottom wall 1511 of housing 1510. Bottom wall 1511 may be in contact with the user's skin (e.g., represented by dashed line 1550). In some embodiments, the vibration plate of bone conduction speaker 1520 may be mechanically connected to the bottom wall of housing 1510, or the bottom wall of housing 1510 may be part of bone conduction speaker 1520 and considered its vibration plate. In this case, the vibration plate may vibrate perpendicularly or substantially perpendicularly to the user's skin (dashed line 1550). In some alternative embodiments, the bone conduction speaker 1520 may be located on an upper wall of the housing 1510 , the upper wall being opposite to the bottom wall of the housing 1510 .

[0141] The air conduction speaker 1530 may be arranged vertically relative to the bone conduction speaker 1520. That is, the vibration direction of the vibration plate of the bone conduction speaker 1511 may be perpendicular to the central vibration direction of the diaphragm of the air conduction speaker 1530. Figure 15 As shown, the diaphragm 1512 of the air conduction speaker 1530 can form a side wall of the housing 1510, so that the front cavity 1530 of the air conduction speaker does not exist. The front side of the diaphragm of the air conduction speaker 1530 can face the listening position. The air-conducted sound waves generated by the air conduction speaker 1530 can be directly propagated in the listening direction. In some alternative embodiments, the side wall of the housing 1510 can be provided in front of the diaphragm of the air conduction speaker 1530, thereby forming a front cavity of the air conduction speaker 1530. The air-conducted sound waves generated by the air conduction speaker 1530 can be propagated in the listening direction through the sound holes provided in the wall of the front cavity.

[0142] In some embodiments, the vibration direction of bone conduction speaker 1520 (i.e., the direction in which bone-conducted sound waves propagate out of bone conduction speaker 1520) can be perpendicular to the user's skin (indicated by dashed line 1550), and the central vibration direction of the diaphragm of air conduction speaker 1530 can be parallel to the user's skin (indicated by dashed line 1550). In this case, the central vibration direction of the diaphragm of air conduction speaker 1530 can be substantially perpendicular to the vibration direction of bone conduction speaker 1520. The vibration of bone conduction speaker 1520 (or the bone-conducted sound waves generated by bone conduction speaker 1520) can have little or no effect on the vibration of the diaphragm of air conduction speaker 1520, thereby achieving a better sound quality for acoustic output device 1500. It should be noted that the central vibration direction of the diaphragm of air conduction speaker 1530 may not be completely perpendicular to the vibration direction of bone conduction speaker 1520. For example, the angle between the two directions can be greater than or less than 90 degrees (e.g., 70 degrees, 80 degrees, 85 degrees, 95 degrees, 100 degrees, 115 degrees, etc.).

[0143] Bone conduction speaker 1520 may be electrically coupled to bone conduction signal processing circuit 316. Bone conduction speaker 1520 may generate and output bone conduction sound waves within a specific frequency range (e.g., low frequency range, mid-frequency range, high frequency range, mid-low frequency range, mid-high frequency range, etc.) based on a bone conduction control signal generated by bone conduction signal processing circuit 316. Air conduction speaker 1530 may be electrically coupled to air conduction signal processing circuit 317. Air conduction speaker 1530 may generate and output air conduction sound waves within the same or a different frequency range as bone conduction speaker 1520 based on an air conduction control signal generated by air conduction signal processing circuit 317.

[0144] For example, bone-conducted sound waves can include mid- and high-frequency sound waves, while air-conducted sound waves can include mid- and low-frequency sound waves. The mid- and low-frequency air-conducted sound waves can complement the mid- and high-frequency bone-conducted sound waves. The total output of the acoustic output device can cover both mid- and low-frequency sound waves. This provides better sound quality (especially at low frequencies) and avoids the strong vibrations of the bone-conducted speaker at low frequencies.

[0145] More detailed information on the frequency distribution of bone-conducted sound waves and / or air-conducted sound waves can be found elsewhere in this specification, e.g. Figure 17-21 .

[0146] It should be noted that the above description is provided for illustrative purposes only and is not intended to limit the scope of this specification. For those skilled in the art, various changes and modifications can be made based on the description of this specification. However, these changes and modifications do not depart from the scope of this specification. For example, the number, position, size and / or shape of the sound holes and pressure relief holes provided in the acoustic output device may not be limited to the embodiments shown in the figures. In some embodiments, the sound tube may be coupled to the sound hole. In some alternative embodiments, the sound tube may be directly inserted into the housing 1510 through the wall. For another example, the relative position of the bone conduction speaker 1520 and the air conduction speaker 1530, the mass, shape and / or size of the housing 1510, one or more additional acoustic structures, etc., can be modified and optimized according to various needs and are not limited in this specification. For another example, the bone conduction speaker 1520 and the air conduction speaker 1530 can be respectively accommodated in two housings.

[0147] Figure 16 is a schematic diagram of a leakage frequency response curve of the acoustic output device 1500 according to some embodiments of the present specification. The air conduction speaker 1530 of the acoustic output device 1500 may be embedded in the side wall 1512 of the housing 1510. In this case, the mass and stiffness of the side wall 1512 may be increased, and the vibration of the housing 1510 may be reduced, thereby reducing the sound leakage of the acoustic output device 1500. Leakage frequency response curves of the acoustic output device 1500 under various conditions may be provided. The horizontal axis may represent the frequency of the sound. The vertical axis may represent the amount of sound leakage of the acoustic output device 1500. As Figure 16 As shown, under the condition that the acoustic output device 1500 includes only the bone conduction speaker 1520 (omitting the air conduction speaker 1530), a first leakage frequency response curve 1610 is provided. A second leakage frequency response curve 1620 is provided, which represents the sound leakage of the acoustic output device 1500 at different frequencies.

[0148] According to the leakage frequency response curves 1610 and 1620 , it can be inferred that, in a specific frequency range (eg, 150 Hz-10,000 Hz), the sound leakage 1500 of the acoustic output device 1500 is smaller than the sound leakage of the acoustic output device including only a bone conduction speaker.

[0149] Figure 17-211 is a diagram illustrating a frequency response characteristic curve of an acoustic output device according to some embodiments of this specification. An acoustic output device (e.g., acoustic output device 600, 700, 800, 1100, 1200, or 1500) may include a bone conduction speaker and an air conduction speaker. The bone conduction speaker and the air conduction speaker may be independent of each other. The bone conduction speaker and the air conduction speaker may generate sound waves of different frequencies (e.g., mid-low frequencies, mid-high frequencies, etc.). The sound waves of different frequencies may complement each other to achieve a specific output effect.

[0150] like Figure 17 As shown, the bone conduction sound waves generated by the bone conduction speaker and the air conduction sound waves generated by the air conduction speaker may include different frequencies. In some embodiments, the bone conduction sound waves may include mid-high frequencies ( Figure 17 The short dashed line in the figure indicates that air-conducted sound waves can include medium and low frequencies (denoted by Figure 17 The air-conducted sound waves including mid-low frequencies (i.e., mid-low frequency sounds) can be transmitted through the air to the ears of the user wearing the acoustic output device, and the bone-conducted sound waves including mid-high frequencies (i.e., mid-high frequency sounds) can be transmitted to the user through the user's bones. The mid-low frequency sounds can be used as a supplement to the mid-high frequency sounds. The total output of the acoustic output device (given by Figure 17 The solid line in the figure indicates that the mid-low frequency and the mid-high frequency can be covered. In this case, better sound quality (especially in the low frequency) can be provided, and the strong vibration of the bone conduction speaker in the low frequency can be avoided.

[0151] Generally speaking, human hearing is more sensitive to mid- and high-frequency sounds, and human touch is more sensitive to low-frequency sounds. In some embodiments, bone conduction sound waves may include mid- and low-frequency sounds ( Figure 17 The air-conducted sound waves can include medium and high frequencies (denoted by the dashed line in Figure 17 In this case, the acoustic output device can provide a prompt or warning to the user via a bone conduction speaker and / or an air conduction speaker because the user is sensitive to bone-conducted sound waves in the low-mid frequencies and / or air-conducted sound waves in the high-mid frequencies. It should be noted that the low-mid frequencies and the high-mid frequencies can overlap with each other. For example, the maximum frequency of the low-mid frequencies (e.g., the frequency corresponding to the half-power point of the low-mid frequency curve) can be greater than the minimum frequency of the high-mid frequencies (e.g., the frequency corresponding to the half-power point of the high-mid frequency curve). In some alternative embodiments, the low-mid frequencies and the high-mid frequencies may not overlap with each other.

[0152] In some embodiments, the bone-conducted sound waves and the air-conducted sound waves may comprise the same frequency. Figure 18 As shown, the bone conduction speaker and the air conduction speaker of the acoustic output device can generate sound waves of different frequencies (for example, frequencies within a wide frequency range (also known as Figure 18The wide range of frequencies represented by the short dashed line), or the frequencies within a narrower frequency range (also called the Figure 18 The narrow frequency range indicated by the dashed line in the middle)). Sound waves of different frequencies can complement each other to achieve a specific sound effect. In some embodiments, the bone-conducted sound waves and the air-conducted sound waves can include the same frequency in the low-medium frequency range. In this case, the total output of the sound waves in the low-medium frequency range of the acoustic output device (denoted by Figure 18 The solid line in the figure (indicated by the solid line) can be greater in the mid- and high-frequency range. In other words, the total output of the acoustic output device can be enhanced in the mid- and low-frequency range. Since the human hearing threshold is higher in the mid- and low-frequency range and lower in the mid- and high-frequency range (i.e., people are more sensitive to mid- and high-frequency sounds), the enhanced output of sound waves in the mid- and low-frequency range can compensate for the impact of this hearing threshold, thereby balancing the sounds heard by people across various frequencies.

[0153] In some embodiments, air-conducted sound waves can include mid- and low-frequency frequencies, while bone-conducted sound waves can include frequencies within a wider frequency range (wide-range frequency) than air-conducted sound waves. This enhances the output of mid- and low-frequency frequencies and improves sound quality. At the same time, strong vibrations at mid- and low-frequency frequencies can be avoided, thereby enhancing user comfort and hearing safety. In some embodiments, bone-conducted sound waves can include mid- and low-frequency frequencies, while air-conducted sound waves can include frequencies within a wider frequency range (wide-range frequency) than bone-conducted sound waves. By adding moderate vibrations to the mid- and low-frequency frequencies, the user's tactile sensation can be enhanced alongside the auditory sensation, enriching the user's audio experience.

[0154] like Figure 19 As shown, the bone conduction sound waves and the air conduction sound waves can include the same frequency in the mid-high frequency range to increase the volume of the mid-high frequency or reduce the sound leakage of the mid-high frequency. In some embodiments, the air conduction sound waves can include the mid-high frequency (e.g., Figure 19 The bone conduction sound waves can include frequencies within a wider frequency range (wide frequency range) than the air conduction sound waves. According to the principle of phase cancellation, the air conduction sound waves can reduce or eliminate the sound leakage of the bone conduction speaker in the middle and high frequencies (for example, by Figure 19 In this case, the total sound leakage of the acoustic output device (given by Figure 19 The solid line in the figure can be reduced at mid- and high-frequency levels.

[0155] like Figure 20 As shown, bone conduction sound waves may include medium and high frequencies (e.g., Figure 20 The narrow range of frequencies represented by the dashed line in FIG), air-conducted sound waves can include a wider range of frequencies than bone-conducted sound waves (e.g., Figure 20The short dashed line in the figure indicates a wide range of frequencies) to increase the total output of mid- and high-frequency sound waves (represented by the Figure 20 ) (e.g., increasing the volume of the acoustic output device in the mid-high frequency range).

[0156] In actual application scenarios, for headphones equipped with air conduction speakers, the bone conduction sound waves generated by the bone conduction speakers can serve as a supplement to the mid- and high-frequency sounds of the air conduction speakers. Since the vibration amplitude of the bone conduction speakers is large in the low-frequency range, the user's facial vibration will be more obvious, resulting in a poor user experience. In order to reduce or eliminate vibrations, the low-frequency sound of the bone conduction speakers can be suppressed (for example, by a frequency divider or crossover), which can cause a sharp drop in the low frequency of the bone conduction speakers, thereby reducing the sound quality. However, air conduction speakers can be used to supplement low frequencies. Specifically, the acoustic output device can output low-frequency sounds through the air conduction speakers, and output mid-frequency and / or high-frequency sounds through the bone conduction speakers, so as to obtain a balanced audio experience for the user.

[0157] like Figure 21 As shown, bone conduction speakers can output high-frequency sounds (by Figure 21 ), and the air conduction speaker can output low-frequency sounds (indicated by the short dashed line in Figure 21 The dotted line in the figure indicates the sound output device. The acoustic output device can output both high-frequency and low-frequency sounds, thereby improving user comfort and maintaining acoustic effects. In some embodiments, high-frequency sounds may refer to frequencies greater than 300 Hz, 1000 Hz, 10 kHz, and the like. Correspondingly, low-frequency sounds may refer to frequencies less than 250 Hz, 500 Hz, 1 kHz, and the like.

[0158] Figure 22 FIG. 1 is a schematic diagram of the vibration displacement spectrum of a bone conduction speaker according to some embodiments of this specification. The vibration displacement of the bone conduction speaker at different frequencies can be measured by a laser vibrometer. Figure 22 As shown, the resonance peak of the bone conduction speaker is about 180Hz. The vibration amplitude of the bone conduction speaker increases rapidly at about 100Hz-250Hz, which can be a vibration-sensitive area. In some embodiments, the crossover point of the bone conduction speaker and the air conduction speaker can be set at about 250Hz. Therefore, the air conduction speaker can mainly generate air-conducted sound waves with a frequency less than 250Hz, and the bone conduction speaker can mainly generate bone-conducted sound waves with a frequency higher than 250Hz. As a result, the vibration amplitude of the bone conduction speaker can be kept within a smaller range, thereby effectively reducing the user's facial vibration sensation and balancing the acoustic effect.

[0159] The basic concepts have been described above. It will be apparent to those skilled in the art after reading this application that the above disclosures are provided for illustrative purposes only and do not constitute limitations on this specification. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements, and revisions to this specification. Such modifications, improvements, and revisions are suggested in this specification and remain within the spirit and scope of the exemplary embodiments of this specification.

[0160] This specification also uses specific terms to describe the embodiments of this specification. For example, "one embodiment," "an embodiment," and "some embodiments" refer to a feature, structure, or characteristic associated with at least one embodiment of this specification. Therefore, it should be emphasized and noted that the mention of "one embodiment," "an embodiment," or "an alternative embodiment" two or more times in different locations in this specification does not necessarily refer to the same embodiment. Furthermore, certain features, structures, or characteristics of one or more embodiments of this specification may be appropriately combined.

[0161] Furthermore, those skilled in the art will appreciate that various aspects of this specification may be illustrated and described in terms of any number of patentable categories or situations, including any new and useful process, machine, product, or combination of substances, or any new and useful improvement thereof. Accordingly, various aspects of this specification may be implemented entirely in hardware, entirely in software (including firmware, resident software, microcode, etc.), or in a combination of software and hardware implementations, all of which are generally referred to herein as "modules," "units," "components," "devices," or "systems." Furthermore, various aspects of this specification may take the form of a computer program product embodied in one or more computer-readable media having computer-readable program code thereon.

[0162] A computer-readable signal medium may include a propagated data signal embodying computer program code, for example, in baseband or as part of a carrier wave. Such propagated signals may take a variety of forms, including electromagnetic, optical, or any suitable combination. A computer-readable signal medium may be any computer-readable medium, other than a computer-readable storage medium, that can be coupled to an instruction execution system, apparatus, or device to communicate, propagate, or transfer a program for use. Program code on a computer-readable signal medium may be propagated via any suitable medium, including radio, cable, fiber optic cable, RF, or any combination of the foregoing.

[0163] The computer program code for performing the operations of various aspects of this specification can be written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Java, Scala, Smalltalk, Eiffel, JADE, Emerald, C++, C#, VB.NET, Python, etc., traditional procedural programming languages ​​such as the "C" programming language, Visual Basic, Fortran 2003, Perl, COBOL 2002, PHP, ABAP, dynamic programming languages ​​such as Python, Ruby, and Groovy, or other programming languages. The program code can be executed entirely on the user's computer, or as a stand-alone software package on the user's computer, or partly on the user's computer and partly on a remote computer, or entirely on a remote computer or server. In the latter case, the remote computer can be connected to the user's computer via any type of network, including a local area network (LAN) or a wide area network (WAN), or can be connected to an external computer (e.g., by using the network of a network service provider) or in a cloud computing environment or provided as a service, such as software as a service (SaaS).

[0164] In addition, unless expressly stated in the claims, the order of the processing elements and sequences, the use of alphanumeric characters, or the use of other names described in this specification are not intended to limit the order of the processes and methods of this specification. Although the above disclosure discusses some embodiments of the invention that are currently considered useful through various examples, it should be understood that such details are for illustrative purposes only, and the appended claims are not limited to the disclosed embodiments. On the contrary, the claims are intended to cover all modifications and equivalent combinations that are consistent with the spirit and scope of the embodiments of this specification. For example, although the implementation of the various components described above can be embodied in a hardware device, it can also be implemented as a pure software solution, for example, installation on an existing server or mobile device.

[0165] Similarly, it should be noted that, in order to simplify the presentation of this specification and thereby facilitate understanding of one or more embodiments of the invention, the foregoing descriptions of the embodiments of this specification sometimes combine various features into a single embodiment, figure, or description thereof. However, this approach should not be interpreted as reflecting an intention that the claimed object material to be scanned requires more features than expressly recited in each claim. In practice, an embodiment may have fewer features than all of the features of a single disclosed embodiment.

Claims

1. An open acoustic output device, comprising: a bone conduction speaker, wherein the bone conduction speaker vibrates to generate bone conduction sound waves; an air conduction speaker, the air conduction speaker including a diaphragm, the diaphragm vibrating to generate air-conducted sound waves, the air conduction speaker being independent of the bone conduction speaker; as well as at least one housing configured to accommodate the bone conduction speaker and the air conduction speaker, wherein the vibration direction of the bone conduction speaker and the central vibration direction of the diaphragm of the air conduction speaker form an angle of 70°-115°; Wherein, the bone conduction speaker includes a vibration component, and the vibration component includes: a magnetic circuit system configured to generate a magnetic field; a vibration plate connected to the at least one housing; and One or more coils are disposed in the magnetic field and connected to the vibration plate, wherein the one or more coils can drive the vibration plate to vibrate to generate the bone conduction sound waves.

2. The open acoustic output device according to claim 1, wherein The difference between the angle formed by the vibration direction of the bone conduction speaker and the central vibration direction of the diaphragm of the air conduction speaker and 90° is less than a threshold degree, and the threshold degree is 10°.

3. The open acoustic output device according to claim 2, wherein: The threshold degree is 2° or 5°.

4. The open acoustic output device according to claim 1 or 2, wherein: The vibration direction of the bone conduction speaker is perpendicular to the central vibration direction of the diaphragm of the air conduction speaker.

5. The open acoustic output device according to claim 1, wherein: The bottom wall of the at least one housing is a vibration plate of the bone conduction speaker; Alternatively, the vibration plate of the bone conduction speaker is mechanically connected to the bottom wall of the at least one housing.

6. The open acoustic output device according to claim 1, wherein: The air conduction speaker includes a driver and a diaphragm, wherein the driver drives the diaphragm to vibrate to generate the air conduction sound waves.

7. The open acoustic output device according to claim 1, wherein: The air conduction speaker is arranged next to the bone conduction speaker.

8. The open acoustic output device according to claim 1, wherein: The at least one housing includes a first housing and a second housing, the bone conduction speaker is accommodated in the first housing, and the air conduction speaker is accommodated in the second housing.

9. The open acoustic output device according to claim 1, wherein: The distance from the air conduction speaker to the listening position is shorter than the distance from the bone conduction speaker to the listening position.

10. The open acoustic output device according to claim 8, wherein The second housing includes a sound hole facing a listening position.

11. The open acoustic output device according to claim 1, wherein: The air conduction speaker and the bone conduction speaker are stacked.

12. The open acoustic output device according to claim 1, wherein: The bone conduction speaker and the air conduction speaker are accommodated in the same housing.

13. The open acoustic output device according to claim 11, wherein: The housing that accommodates the bone conduction speaker and the air conduction speaker includes a housing wall for transmitting the bone conduction sound waves to the outside.

14. The open acoustic output device according to claim 12 or 13, wherein: The housing that houses the bone conduction speaker and the air conduction speaker includes a sound hole facing a listening position.

15. The open acoustic output device according to claim 1 or 2, wherein: The bone conduction speaker and the air conduction speaker are arranged relatively vertically.

16. The open acoustic output device according to claim 1 or 2, wherein: The bone-conducted sound waves include medium and high frequencies, and the air-conducted sound waves include medium and low frequencies.

17. The open acoustic output device according to claim 1 or 2, wherein: The bone-conducted sound waves include medium and low frequencies, and the air-conducted sound waves include medium and high frequencies.

18. The open acoustic output device according to claim 1 or 2, wherein: The air-conducted sound waves include medium and low frequencies, and the bone-conducted sound waves include frequencies within a wider frequency range than the frequencies of the air-conducted sound waves.

19. The open acoustic output device according to claim 1 or 2, wherein: The bone-conducted sound waves include medium and low frequencies, and the air-conducted sound waves include frequencies in a frequency range wider than that of the bone-conducted sound waves.

20. The open acoustic output device according to claim 1 or 2, wherein: The air-conducted sound waves include medium and high frequencies, and the bone-conducted sound waves include frequencies within a frequency range wider than that of the air-conducted sound waves.

21. The open acoustic output device according to claim 1 or 2, wherein: The bone-conducted sound waves include medium and high frequencies, and the air-conducted sound waves include frequencies within a frequency range wider than that of the bone-conducted sound waves.

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