Acoustic output device

Abstract

The embodiment of the specification provides an acoustic output device. The acoustic output device comprises an acoustic output unit, a contact detection sensor and a processor, wherein the acoustic output unit comprises a vibration unit and a shell, and the shell at least comprises a contact area which is in contact with a face area of a user; the contact detection sensor is located at the contact area; the processor is configured to judge whether a user wears the acoustic output device or not based on an electric signal generated when the contact detection sensor makes contact with the face area of the user.

Description

Acoustic output device Technical Field

[0001] This specification relates to the field of acoustic technology, and in particular to an acoustic output device. Background Art

[0002] In the current headphone market, wearing detection sensors are widely used in products such as TWS headphones. A typical application is to automatically wake up the system when it is recognized that the user is wearing the headphones, and automatically enter standby mode when it is recognized that the user has taken off the headphones, thereby achieving the purpose of reducing power consumption and extending the use time. At the same time, it saves the user's operating steps and greatly improves the user experience. However, due to the great differences in wearing methods of headphones with different structures, the currently used sensor solutions based on in-ear detection are difficult to directly transplant to headphones with open wearing methods (that is, headphones whose shells are located near the ear canal but do not block the ears). For example, the existing open-ear headphones on the market do not have a wearing detection function, which leads to a large gap in user experience compared to other headphones, and also brings many problems such as power consumption.

[0003] Based on this, it is necessary to provide a new wearing detection solution.

[0004] Summary of the Invention

[0005] An embodiment of the present specification may provide an acoustic output device, comprising: an acoustic output unit, a contact detection sensor, and a processor; wherein the acoustic output unit includes a vibration unit and a shell, the shell including at least a contact area that contacts the user's facial area; the contact detection sensor is located at the contact area; the processor is configured to determine whether the user is wearing the acoustic output device based on an electrical signal generated when the contact detection sensor contacts the user's facial area.

[0006] In some embodiments, the contact detection sensor includes an inductive element, a piezoelectric element, and a processing chip. The piezoelectric element is connected to the inner surface of the contact area, the piezoelectric element generates vibration based on a preset voltage, the inductive element and the piezoelectric element are connected in parallel to form a loop, and the processing chip is used to read the resonant frequency of the loop.

[0007] In some embodiments, the contact detection sensor further includes a capacitive element connected in parallel with the piezoelectric element.

[0008] In some embodiments, the contact detection sensor includes a first piezoelectric element and a receiving element arranged in a stacked manner, wherein the side of the first piezoelectric element facing away from the receiving element is connected to the inner surface of the contact area, and the first piezoelectric element generates vibration based on a preset voltage. When the user touches the contact area, the vibration state of the first piezoelectric element changes.

[0009] In some embodiments, the resonant frequency of the first piezoelectric element is not less than 20 kHz.

[0010] In some embodiments, the receiving element includes an air conduction microphone or a second piezoelectric element.

[0011] In some embodiments, the contact detection sensor further includes a substrate, and the first piezoelectric element, the receiving element, and the substrate are stacked.

[0012] In some embodiments, the contact detection sensor includes a stacked substrate, a first circuit board, and a resistive film layer, wherein the substrate is connected to the inner surface of the contact area, and the contact detection sensor deforms in response to the deformation of the contact side wall and converts the deformation into an electrical signal.

[0013] In some embodiments, the resistive thin film layer includes at least two sensitive thin film resistors and at least two fixed thin film resistors, and the at least two sensitive thin film resistors and the at least two fixed thin film resistors are electrically connected to form a bridge circuit.

[0014] In some embodiments, a surface of the substrate connected to the first circuit board is provided with a plurality of grooves, and the plurality of grooves include at least two grooves respectively facing the at least two sensitive thin film resistors.

[0015] In some embodiments, the contact detection sensor includes a second circuit board, one side of the second circuit board is connected to a side of the substrate facing away from the first circuit board, and the other side of the second circuit board is provided with a capacitor electrode.

[0016] In some embodiments, the vibration unit is elastically connected to the housing via a vibration transmission piece, and along the vibration direction of the vibration unit, a distance between the contact detection sensor and the vibration transmission piece is greater than 300 um.

[0017] In some embodiments, the vibration unit is elastically connected to the shell via a vibration transmission plate, the vibration transmission plate includes a hollow area, and the projection of the contact detection sensor along the vibration direction of the vibration unit is within the hollow area.

[0018] In some embodiments, the acoustic output device further comprises a coupling circuit, wherein the contact detection sensor is located on an outer surface of the contact area, the coupling circuit is located on an inner surface of the contact area, and the coupling circuit is wirelessly coupled to the contact detection sensor.

[0019] In some embodiments, the coupling circuit includes a first inductance element, a first capacitance element and a processing chip, and the contact detection sensing device includes a second capacitance element and a second inductance element, wherein the first inductance element and the first capacitance element are connected in parallel to form a first loop, and the second inductance element and the second capacitance element are connected in parallel to form a second loop, and the processing chip is used to read the resonant frequency after the first loop and the second loop are coupled.

[0020] In some embodiments, the coupling circuit includes a third circuit board, one side of which is connected to the inner surface of the contact area, and the first inductor element, the first capacitor element and the processing chip are located on a side of the third circuit board away from the contact area.

[0021] In some embodiments, the second capacitive element and the second inductive element are located on an outer surface of the contact area, and the second inductive element is disposed opposite to the first inductive element.

[0022] In some embodiments, the second capacitive element is a pressure-sensitive capacitor, and the capacitance value of the second capacitive element changes with the pressure applied.

[0023] In some embodiments, the contact detection device includes a fourth circuit board, one side of the fourth circuit board is connected to the outer surface of the contact area, and the second capacitor and the second inductor are located on a side of the fourth circuit board away from the contact area.

[0024] In some embodiments, an outer surface of the contact area of ​​the housing is provided with a protective layer, and the protective layer covers the contact detection sensor.

[0025] In some embodiments, the processor is further configured to issue a control instruction in response to a user wearing the acoustic output device, wherein the control instruction changes an operating state of the acoustic output device.

[0026] In some embodiments, the acoustic output device further includes an ear hook, one end of the ear hook is connected to the acoustic output unit, and the ear hook hangs the acoustic output unit near the user's ear.

[0027] In some embodiments, the acoustic output device also includes a rear hook, the ear hook includes a first ear hook and a second ear hook, the acoustic output unit includes a first acoustic output unit and a second acoustic output unit, the first ear hook is connected to the first acoustic output unit and the rear hook, the second ear hook is connected to the second acoustic output unit and the rear hook, the first ear hook hangs the first acoustic output unit near one ear of the user, the second ear hook hangs the second acoustic output unit near the other ear of the user, and the first ear hook and the second ear hook are connected through the rear hook.

[0028] Additional features will be described in part in the following description and will become apparent to those skilled in the art by reference to the following and accompanying drawings, or may be learned by practice or operation of the examples. The features of this specification may be realized and obtained by practicing or using the various aspects of the methods, tools, and combinations described in the following detailed examples. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] This specification will be further described in the form of exemplary embodiments, which will be described in detail with reference to the accompanying drawings. These embodiments are not limiting, and in these embodiments, like numbers represent like structures, wherein:

[0030] FIG1 is a schematic diagram of a framework of an exemplary acoustic output device according to some embodiments of this specification;

[0031] FIG2 is a schematic structural diagram of an exemplary acoustic output device according to some embodiments of this specification;

[0032] FIG3 is a schematic structural diagram of an exemplary contact area of ​​a user acting on an acoustic output device according to some embodiments of this specification;

[0033] FIG4 is a circuit diagram of a contact detection sensor of an exemplary acoustic output device according to some embodiments of the present specification;

[0034] FIG5 is a diagram illustrating a frequency response of a contact detection sensor of an exemplary acoustic output device according to some embodiments of the present specification;

[0035] FIG6 is a schematic structural diagram of an exemplary acoustic output device according to other embodiments of this specification;

[0036] FIG7 is a schematic structural diagram of an exemplary acoustic output device according to other embodiments of this specification;

[0037] FIG8 is a schematic diagram of a bridge circuit of a contact detection sensor of an acoustic output device according to some embodiments of this specification;

[0038] FIG9 is a schematic structural diagram of an exemplary acoustic output device according to other embodiments of this specification;

[0039] FIG10 is a schematic structural diagram of an exemplary acoustic output device according to other embodiments of this specification;

[0040] FIG11 is a schematic structural diagram of an exemplary acoustic output device according to other embodiments of this specification;

[0041] FIG12 is a schematic structural diagram of an exemplary acoustic output device according to other embodiments of this specification;

[0042] FIG13 is a schematic structural diagram of an exemplary acoustic output device according to other embodiments of this specification;

[0043] FIG14 is a schematic diagram illustrating a coupling principle of a contact detection sensor of an exemplary acoustic output device according to some embodiments of this specification;

[0044] FIG15 is a schematic structural diagram of an exemplary acoustic output device according to some embodiments of this specification;

[0045] FIG16 is a schematic structural diagram of an exemplary acoustic output device according to other embodiments of this specification;

[0046] FIG17A is a schematic diagram of an exemplary earphone in a free-standing state according to some embodiments of the present specification;

[0047] FIG17B is a schematic diagram of an exemplary headset in a normal wearing state according to some embodiments of this specification; and

[0048] FIG17C is a schematic diagram of an exemplary headset in an abnormal wearing state according to some embodiments of this specification. Specific embodiments

[0049] In order to more clearly illustrate the technical solutions of the embodiments of this specification, the following is a brief introduction to the drawings required for the description of the embodiments. Obviously, the drawings described below are only some examples or embodiments of this specification. For ordinary technicians in this field, this specification can also be applied to other similar scenarios based on these drawings without paying any creative work. It should be understood that these exemplary embodiments are provided only to enable technicians in the relevant fields to better understand and implement this specification, and do not limit the scope of this specification in any way. Unless it is obvious from the language environment or otherwise explained, the same reference numerals in the figures represent the same structure or operation.

[0050] As used in this specification and claims, unless the context clearly indicates an exception, the words "a", "an", "an" and / or "the" do not specifically refer to the singular and may also include the plural, unless the context clearly indicates an exception. Generally speaking, the terms "include" and "comprise" only indicate the inclusion of the steps and elements that have been explicitly identified, and these steps and elements do not constitute an exclusive list. The method or apparatus may also include other steps or elements. The term "based on" means "at least in part based on." The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one other embodiment."

[0051] In the description of this specification, it should be understood that the terms "front", "rear", "ear hook", "rear hook", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing this specification and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on this specification.

[0052] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. Throughout this specification, "plurality" means at least two, such as two or three, unless otherwise specifically defined.

[0053] In this specification, unless otherwise specified or limited, the terms "mounted," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two components or interaction between two components, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in this specification based on specific circumstances.

[0054] Embodiments of this specification provide an acoustic output device that can analyze the current usage state of the acoustic output device (e.g., normal wearing state, abnormal wearing state, or free placement state) using a contact detection sensor, thereby further adjusting the operating state of one or more electronic components of the acoustic output device (e.g., a Bluetooth module, battery, etc.) based on the current usage state of the acoustic output device. In some embodiments, multiple sensors (e.g., the same or different types of sensors) can be used to detect the current usage state of the acoustic output device, thereby improving the accuracy of wearing detection of the acoustic output device. In some embodiments, the contact detection sensor can be located on the inner surface of the contact area of ​​the acoustic output device's housing, thereby avoiding the need to drill holes in the housing and preventing damage to the housing's integrated design, thereby improving the sealing and waterproof performance of the acoustic output device to a certain extent. In some embodiments, the contact detection sensor can be located on the outside of the acoustic output device's housing and transmit the signal detected by the contact detection sensor to a processing chip inside the housing via wireless coupling. This can improve the sensitivity of the contact detection sensor while ensuring the sealing and waterproof performance of the acoustic output device.

[0055] The acoustic output device provided in the embodiments of this specification is described in detail below with reference to the accompanying drawings.

[0056] FIG1 is a schematic diagram of a framework of an acoustic output device according to some embodiments of this specification.

[0057] 1 , the acoustic output device 100 may include an acoustic output unit 110 , a contact detection sensor 120 , and a processor 130 . The acoustic output unit 110 and the contact detection sensor 120 are both electrically connected to the processor 130 .

[0058] The acoustic output unit 110 is configured to generate a sound signal based on an electrical signal (also referred to as an audio signal). In some embodiments, the acoustic output unit may include a bone conduction speaker and / or an air conduction speaker, and accordingly, the sound signal may be a bone-conducted sound wave and / or an air-conducted sound wave. In some embodiments, the acoustic output unit 110 may be a bone-conducted speaker, in which case the acoustic output unit 110 may include a vibration unit and a housing, wherein the housing includes at least a contact area capable of contacting the user's facial area. In some embodiments, the contact area may be a side wall of the housing. For example, when the housing is a cylindrical structure, the contact area is the bottom wall of the housing. In some embodiments, the contact area may also be a local area of ​​a side wall of the housing. For example, a side wall of the housing may have a protrusion protruding relative to its surface, and the protrusion is the contact area. The vibration unit may receive an electrical signal from the processor 130 and convert the electrical signal into a corresponding vibration signal (also referred to as mechanical vibration). In some embodiments, the vibration signal may be transmitted to the user's skin or bones via the housing, thereby outputting the sound to the user via bone conduction. In some embodiments, the acoustic output unit 110 may be an air conduction speaker, in which case the air conduction speaker may include a housing, a transducer, and a diaphragm. The transducer and diaphragm are located inside the housing. The transducer may receive an electrical signal from the processor 130 and drive the diaphragm to vibrate, thereby generating air-conducted sound waves. In some embodiments, the air conduction speaker may be an open structure, located near the user's ear but not blocking the ear canal. Accordingly, its housing includes at least a contact area that can contact the user's facial area. In some embodiments, the transducer may include an electromagnetic type (e.g., a moving coil type, a moving iron type, etc.), a piezoelectric type, an inverse piezoelectric type, an electrostatic type, etc. In some embodiments, the housing may include one or more sound guide holes. When the user wears the acoustic output device 100, the sound guide holes face the user's ear canal opening. The sound guide holes are used to connect the housing cavity inside the housing with the outside world. The sound guide holes can transmit the air-conducted sound waves inside the housing to the outside world, thereby transmitting the sound to the user in an air-conducted manner.

[0059] The contact detection sensor 120 can be set at the contact area of ​​the aforementioned shell and generate a corresponding electrical signal based on the contact state between the user's face and the contact area. The "contact area of ​​the shell" mentioned here can include the area on the shell that contacts the face, which is located on the outer surface of the shell (also called the outer surface of the contact area), and can also include the inner side of the shell opposite to the direct contact area, which is located on the inner surface of the shell (also called the inner surface of the contact area), and the projection of the face coincides or approximately coincides with the projection of the direct contact area. In addition, the electrical signal generated by the contact detection sensor 120 here is different from the "electrical signal" in the acoustic output unit 110 described above, which is configured to generate a sound signal based on the electrical signal (also called the audio signal). This is explained here for the sake of distinction. In some embodiments, the contact detection sensor 120 can include any one or more of an ultrasonic sensor, a resistive sensor (e.g., a resistive pressure sensor), and a capacitive sensor (e.g., a capacitive pressure sensor, a capacitive skin sensor). In some embodiments, the contact detection sensor 120 can be set on the inner surface of the contact area of ​​the shell of the acoustic output device. In some embodiments, the contact detection sensor 120 may also be disposed on the outer surface of the contact area of ​​the housing, and transmit the signal detected by the contact detection sensor to a processing chip disposed inside the housing via wireless coupling. In some embodiments, the contact detection sensor may also be an optical sensor (e.g., an infrared sensor). For more information about the contact detection sensor 120, please refer to other locations in this specification (e.g., Figures 2 to 14 and their related descriptions) and will not be repeated here.

[0060] The processor 130 can be configured to determine whether the user is currently wearing the acoustic output device 100 based on the electrical signal generated by the contact detection sensor 120 when the contact area changes when in contact with the user's face. In some embodiments, the processor 130 can also analyze the current usage state of the acoustic output device 100 based on the above-mentioned determination result, and control the operating state of the acoustic output device 100 based on the current usage state. For example, when the electrical signal generated by the contact detection sensor 120 determines that the acoustic output device 100 is currently in a normal wearing state, the processor 130 can wake up the acoustic output device 100 and control the acoustic output device 100 to automatically connect to Bluetooth and / or play music. Conversely, when it is determined that the acoustic output device 100 is currently in an abnormal wearing state or is in a free-standing state, the processor 130 can control the acoustic output device 100 to stop playing music or disconnect the Bluetooth connection, and enter standby mode after this state continues for a period of time (e.g., 10 seconds, 15 seconds, etc.).

[0061] FIG2 is a schematic structural diagram of an acoustic output device shown in some embodiments of this specification.

[0062] 2 , in some embodiments, the housing 113 of the acoustic output unit 110 may include a contact area capable of contacting the user's face, such as a contact surface 111 or a partial area of ​​the contact surface 111. The side opposite the contact surface 111 may include an outer side surface 112, which faces away from the user's facial area when worn by the user. In some embodiments, the housing 113 may be a structure having an internal accommodating cavity, and the vibration unit is disposed within the accommodating cavity of the housing 113. In some embodiments, the contact surface 111 and the outer side surface 112 may include a plane, an arc surface, or other irregular shapes. When the contact surface 111 and the outer side surface 112 are both planes, the contact surface 111 and the outer side surface 112 may be parallel to each other or form an angle of a certain degree (e.g., 0 to 45 degrees). In some embodiments, the contact surface 111 may have a protrusion protruding relative to its surface. The protrusion may be considered as a contact area that contacts the user's face. In this case, the contact detection sensor 120 may be located at the protrusion. In some embodiments, the contact surface 111 and the outer side surface 112 may be connected via other connecting surfaces, which may be flat and / or curved. In some embodiments, the housing 113 may be shaped like a cylinder, a truncated cone, a rectangular parallelepiped, or other three-dimensional structures. In some embodiments, the housing 113 may be made of plastic, resin, glass, metal, or the like.

[0063] In some embodiments, the contact detection sensor 120 can be positioned on the inner or outer surface of the contact surface 111. The inner surface may refer to the side of the contact surface 111 facing away from human skin when normally worn. Conversely, the outer surface may refer to the side of the contact surface 111 that may come into contact with human skin when normally worn. Referring to Figure 2 , in some embodiments, to facilitate wiring and prevent damage to the integrated design of the housing 113, the contact detection sensor 120 can be positioned on the inner surface of the contact surface 111. It will be appreciated that positioning the contact detection sensor 120 on the inner surface of the housing 113 avoids the need for openings in the housing 113, thereby improving the sealing and waterproofing properties of the acoustic output device 100 to a certain extent.

[0064] FIG3 is a schematic structural diagram of a contact area of ​​an acoustic output device applied by a user according to some embodiments of this specification.

[0065] In some embodiments, the contact detection sensor 120 may include an inductive element, a piezoelectric element, and a processing chip. In some embodiments, the piezoelectric element may be connected to the inner surface of the contact area (e.g., contact surface 111) of the housing 113, and the inductive element and the piezoelectric element are connected in parallel to form a loop. In some embodiments, the piezoelectric element may generate vibrations based on a preset drive signal (e.g., a preset voltage signal or current signal), and the processing chip may be used to read the resonant frequency of the loop formed by the piezoelectric element and the inductive element. In some embodiments, the piezoelectric element may include a piezoelectric crystal, a piezoelectric semiconductor, or a piezoelectric ceramic. In some embodiments, the piezoelectric element may be a regular shape such as a rectangle, a rhombus, a circle, an ellipse, or other irregular shapes, which are not specifically limited in this specification.

[0066] Referring to Figure 3 , when human skin 300 (e.g., a user's face or finger) comes into contact with housing 113, the added mass and damping of human skin 300 affects the vibration state of the entire system (e.g., the system consisting of the piezoelectric element and housing 113), thereby changing the system's resonant frequency. In some embodiments, processor 130 can identify the current usage status of acoustic output device 100 based on the resonant frequency read by the processing chip.

[0067] Specifically, in some embodiments, the processor 130 may determine the current usage state of the acoustic output device 100 based on a mapping relationship between the resonant frequency and the usage state. For example, using the time point as the abscissa in a two-dimensional coordinate system, with different time points corresponding to corresponding wearing states, the resonant frequency as the ordinate in the two-dimensional coordinate system, and the experimental data as the data points in the two-dimensional coordinate system, a fitting curve is obtained using the experimental data, or a functional relationship is obtained through an algorithm, and the usage state of the acoustic output device 100 is determined based on the measured resonant frequency. In some embodiments, the processor 130 may process the resonant frequency based on a machine learning model to obtain the current usage state of the acoustic output device 100 corresponding to the resonant frequency. In some embodiments, the machine learning model may be trained using a number of training samples, wherein the training samples may include the resonant frequencies of the acoustic output device 100 under different usage states obtained based on the experimental data, as well as label information corresponding to each resonant frequency. The label information may reflect the current usage state of the acoustic output device 100 corresponding to each resonant frequency, such as normal wearing state, abnormal wearing state, or placement state.

[0068] FIG. 4 is a circuit diagram of a contact detection sensor of an acoustic output device according to some embodiments of this specification.

[0069] Referring to Figure 4 , in some embodiments, the contact detection sensor 120 may include a capacitive element C0 connected in parallel with the piezoelectric element 121 and the inductive element L0 to form a composite LC resonant circuit. The piezoelectric element 121 can function as an electromechanical coupling, coupling the mechanical vibrations between the housing, the piezoelectric element, and the skin into the LC electrical resonance. When the effective stiffness or effective mass of the mechanical system changes, the resonant frequency of the LC resonant system changes. Specifically, when human skin 300 contacts the housing 113 of the acoustic output device 100, the added mass and damping of the skin 300 will cause the resonant frequency measured by the processing chip 220 to decrease.

[0070] The piezoelectric element 121 may have its own equivalent parallel electrostatic capacitance Cp. Therefore, in some embodiments, the capacitor element C0 in the circuit shown in FIG. 4 may be omitted.

[0071] In some embodiments, the processing chip 220 may first send an excitation current of a specific frequency to the LC resonant circuit to cause the circuit to oscillate, then receive the oscillation signal and read the resonant frequency based on the oscillation signal. In some embodiments, the processing chip 220 may obtain the resonant frequency by performing a Fourier transform on the oscillation signal. In some embodiments, determining the usage status of the acoustic output device 100 based on the resonant frequency eliminates the need to measure amplitude changes, providing a more intuitive and sensitive reflection of the current usage status of the acoustic output device 100.

[0072] FIG. 5 is a diagram illustrating a frequency response of a contact detection sensor of an acoustic output device according to some embodiments of this specification.

[0073] Because different parts of the human skin (e.g., fingers, face, etc.) contact different parts of the housing 113 of the acoustic output device 100, they impart different added mass and / or damping to the overall system, resulting in different resonant frequencies for the overall system in different states. Therefore, in some embodiments, the processor 130 can determine the current usage state of the acoustic output device 100 based on this resonant frequency.

[0074] For example, referring to FIG. 5 , where the abscissa represents the time corresponding to signal detection (ms) and the ordinate represents the resonant frequency (Hz), when the user wears the acoustic output device 100 normally and the user's facial skin is in normal contact with the contact area (e.g., contact surface 111) of the housing 113 of the acoustic output device 100, the resonant frequency measured by the processing chip 220 is approximately 4,970,000 Hz, as shown at 310 . When the acoustic output device 100 is not worn normally and the user's facial skin is in contact only with the edge of the contact area (e.g., contact surface 111) of the housing 113 of the acoustic output device 100, the resonant frequency measured by the processing chip 220 is approximately 4,984,000 Hz, as shown at 320 . When the acoustic output device 100 is in a placed state or the user's skin is in contact with a non-contact area (e.g., an area other than the contact surface 111) of the housing 113, the resonant frequency measured by the processing chip 220 is approximately 5,004,000 Hz, as shown at 330 . It should be noted that FIG5 and the data shown therein are only for illustrating the effect of the contact detection sensor in the acoustic output device provided in the embodiment of this specification, and the resonant frequencies measured in different wearing states are not limited to the specific values ​​mentioned above.

[0075] FIG6 is a schematic structural diagram of an acoustic output device shown in other embodiments of this specification.

[0076] 6 , in some embodiments, the contact detection sensor 120 may include a first piezoelectric element 1211 and a receiving element 1212 arranged in a stacked manner, wherein the side of the first piezoelectric element 1211 facing away from the receiving element 1212 is connected to the inner surface of the contact area. In some embodiments, the first piezoelectric element 1211 and the receiving element 1212 may constitute an ultrasonic sensor. The first piezoelectric element 1211 may be configured to generate vibrations based on a preset drive signal (e.g., a preset voltage signal or current signal), and the receiving element 1212 may receive the vibration signal generated by the first piezoelectric element 1211 or the air-conducted sound waves generated by the vibration of the first piezoelectric element 1211 driving the air to vibrate. In some embodiments, the processor 130 may determine the current usage status of the acoustic output device 100 based on the signal received by the receiving element 1212.

[0077] In some embodiments, the receiving element 1212 may include an air conduction microphone. Specifically, the first piezoelectric element 1211 generates mechanical vibrations under the action of a preset driving signal. When the first piezoelectric element 1211 generates mechanical vibrations, it will drive the air near it to vibrate, thereby generating air-conducted sound waves. The air-conducted microphone can receive the air-conducted sound waves generated by the first piezoelectric element 1211 driving the air to vibrate, and convert the air-conducted sound waves into corresponding electrical signals. It should be noted that the first piezoelectric element 1211 can also transmit the vibration to the shell 113. The vibration of the shell 113 will also drive the air near the shell 113 to vibrate, thereby generating air-conducted sound waves. Here, the air-conducted sound waves collected by the air-conducted microphone come from the sound waves generated by the vibration of the first piezoelectric element 1211 and the shell 113 driving the air to vibrate.

[0078] In some embodiments, the receiving element 1212 may include a second piezoelectric element, wherein the second piezoelectric element is stacked with the first piezoelectric element 1211. When the first piezoelectric element 1211 vibrates under the action of a preset driving voltage, since the second piezoelectric element is in contact with the first piezoelectric element 1211, the second piezoelectric element can receive the vibration generated by the coupling of the first piezoelectric element 1211 and the shell 113, and generate a corresponding electrical signal through the piezoelectric effect.

[0079] 6 , in some embodiments, the contact detection sensor 120 may further include a substrate 1213 , wherein a first piezoelectric element 1211 , a receiving element 1212 and the substrate 1213 are stacked, wherein one side of the first piezoelectric element 1211 is connected to the inner surface of the contact surface 111 of the shell 113 , and the receiving element 1212 and the substrate 1213 are sequentially arranged on the side of the first piezoelectric element 1211 facing away from the contact surface 111 .

[0080] It is understood that when human skin contacts the housing 113 of the acoustic output device 100, the additional mass and damping created by the human skin will affect the vibration state of the contact detection sensor and the housing 113, causing the electrical signal received by the receiving element 1212 to change. Therefore, in some embodiments, the processor 130 can determine the current usage state of the acoustic output device 100 by processing the electrical signal received by the receiving element 1212. In some embodiments, the processor 130 can determine the current usage state of the acoustic output device 100 based on the electrical signal received by the receiving element 1212 and the mapping relationship. The mapping relationship can be obtained by processing experimental data, for example, by measuring the electrical signals of the acoustic output device 100 in different wearing states (e.g., normal wearing state, non-wearing state, hand contact, etc.), wherein the experimental data may include a time point and the electrical signals in the wearing states corresponding to different time points, with the time point as the abscissa in a two-dimensional coordinate system, the different time points corresponding to the corresponding wearing states, the electrical signals as the ordinate of the two-dimensional coordinate system, and the experimental data as the data points in the two-dimensional coordinate system. The experimental data is then fitted to obtain a fitting curve, or a functional relationship is obtained through an algorithm. In some embodiments, the processor 130 may process the electrical signals received by the receiving element 1212 based on a machine learning algorithm to determine the current usage state of the acoustic output device 100.

[0081] In some embodiments, to prevent mechanical vibrations generated by the first piezoelectric element 1211 in the contact detection sensor 120, or air-conducted acoustic waves generated by the air, from interfering with the sound signal output by the acoustic output device 100, the resonant frequency of the first piezoelectric element 1211 can be no less than 20 kHz. Specifically, the resonant frequency of the first piezoelectric element 1211 should be within the ultrasonic frequency band, which is inaudible to the human ear. For example, in some embodiments, the resonant frequency of the first piezoelectric element 1211 can be between 20 kHz and 100 kHz; in some embodiments, the resonant frequency of the first piezoelectric element 1211 can be between 25 kHz and 80 kHz.

[0082] The first piezoelectric element 1211 can be in a continuous operating state or a periodic operating state. For example, the first piezoelectric element 1211 can be in an operating state at all times. In another example, the first piezoelectric element 1211 can be operated periodically with a period T, thereby performing periodic contact detection. For example, in some embodiments, the period T can be 2 seconds, 5 seconds, 10 seconds, 20 seconds, 30 seconds, 2 minutes, or another duration. It will be appreciated that, compared to a continuous operating state, periodically operating the first piezoelectric element 1211 can reduce the power consumption of the acoustic output device 100 to a certain extent, thereby extending the battery life of the acoustic output device 100.

[0083] In some embodiments, the operating state of the first piezoelectric element 1211 can be triggered by other sensors. For example, in some embodiments, the acoustic output device 100 may further include an infrared sensor and / or a flexible cavity-based air pressure sensor. The infrared sensor can be used to detect a human body. When the infrared sensor detects a human body, the processor 130 can control the first piezoelectric element 1211 to enter an operating state from a dormant state. Otherwise, the first piezoelectric element 1211 will remain in a dormant state. In some embodiments, the infrared sensor can be disposed within a contact area (e.g., contact surface 111) of the housing 113 or other location capable of detecting a human body. For example, in some embodiments, the acoustic output device 100 may further include a wearing structure (e.g., an ear hook, a back hook, an elastic band, etc.), and the infrared sensor can be disposed on the side of the wearing structure that contacts or faces the user.

[0084] In some embodiments, the air pressure sensor based on the flexible cavity may include at least a flexible cavity and an air pressure sensing unit, the air pressure sensing unit is located in a sealed flexible cavity, the flexible cavity is deformed under the action of an external force, the air pressure inside the flexible cavity changes, and the air pressure sensing unit can convert the air pressure inside the cavity into a corresponding electrical signal. In some embodiments, the acoustic output device 100 may include a wearing structure (e.g., an ear hook, a back hook, an elastic band, etc.), and the air pressure sensor based on the flexible cavity can be set at a position where the wearing structure of the acoustic output device 100 can be deformed during use by the user. When the user wears the acoustic output device 100, the wearing part can be deformed, and the air pressure sensor based on the flexible cavity can generate a corresponding electrical signal based on the deformation of the flexible cavity and feedback it to the processor 130. Further, the processor 130 can control the working state of the first piezoelectric element 1211 according to the electrical signal fed back by the air pressure sensor based on the flexible cavity.

[0085] FIG. 7 is a schematic structural diagram of an acoustic output device shown in some other embodiments of this specification.

[0086] As shown in FIG7 , in some embodiments, the contact detection sensor 120 may include a stacked substrate 1221, a first circuit board 1222, and a resistive film layer 1224. The side of the substrate 1221 facing away from the first circuit board 1222 may be connected to the inner surface of a contact region (e.g., the aforementioned contact surface 111) of the housing of the acoustic output device. The substrate 1221, first circuit board 1222, and resistive film layer 1224 may form a resistive pressure sensor. The contact detection sensor 120 may deform in response to deformation of the contact surface 111 and convert this deformation into a corresponding electrical signal.

[0087] In some embodiments, the substrate 1221 can be made of a hard material. In some embodiments, the substrate 1221 can include a metal material and / or a hard plastic. Exemplary metal materials can include copper, aluminum, alloys, etc., and hard plastics can include polycarbonate (PC), polystyrene (PS), ABS plastic, etc. In some embodiments, one side of the substrate 1221 can be attached to the inner surface of the contact surface 111. The substrate 1221 can produce a corresponding deformation in response to the pressure applied to the contact surface 111 (for example, the contact pressure between the user's face or finger and the contact surface), and transmit the deformation to the resistive film layer 1224.

[0088] In some embodiments, the first circuit board 1222 may be a flexible printed circuit (FPC), and the first circuit board 1222 may be disposed on the side of the substrate 1221 facing away from the contact surface 111. In some embodiments, the resistive film layer 1224 may include at least two sensitive thin film resistors (Rs1 and Rs2 shown in FIG. 7 ) and at least two fixed thin film resistors (not shown in FIG. 7 ). That is, the at least two sensitive thin film resistors and the at least two fixed thin film resistors form the resistive film layer 1224. The fixed thin film resistors may have a fixed resistance value, and the resistance value of the sensitive thin film resistors changes with their own deformation. Specifically, the sensitive thin film resistors may deform in response to the deformation of the substrate 1221, thereby obtaining a corresponding resistance value. In some embodiments, the at least two sensitive thin film resistors and the at least two fixed thin film resistors may be disposed on the side of the first circuit board 1222 facing away from the substrate 1221. In some embodiments, different sensitive thin film resistors and fixed thin film resistors are spaced apart on the side of the first circuit board 1222 facing away from the substrate 1221. In some embodiments, by using a flexible circuit board as the first circuit board 1222 , the deformation requirements of the sensitive thin film resistor can be better adapted.

[0089] 8 , in some embodiments, the at least two sensitive thin-film resistors may include Rs1 and Rs2, and the at least two fixed thin-film resistors may include R1 and R2. The sensitive thin-film resistors Rs1 and Rs2 may be electrically connected to the fixed thin-film resistors R1 and R2 to form a bridge circuit. As shown in FIG8 , the bridge circuit may include an input terminal Vs and a ground terminal GND.

[0090] 7 , in some embodiments, the contact sensor 120 may further include a first protective layer 1223. This first protective layer 1223 may cover the side of the resistive film layer 1224 facing away from the first circuit board 1222 to protect the resistive film layer 1224. It will be appreciated that the provision of the first protective layer 1223 prevents deformation of the resistive film layer 1224 due to contact with components other than the substrate 1221, which could affect the detection results of the contact sensor 120. In some embodiments, the first protective layer 1223 may be made of either a rigid material or a flexible material.

[0091] In some embodiments, a plurality of (e.g., two or more) grooves 1225 may be provided on the surface where the substrate 1221 is connected to the first circuit board 1222. In some embodiments, the plurality of grooves 1225 may include at least two grooves that are respectively opposite to the at least two sensitive thin film resistors. It is understood that in this specification, the groove 1225 and the sensitive thin film resistor are opposite to each other, which can be understood as the center line connecting the groove 1225 and the sensitive thin film resistor being perpendicular to the first circuit board 1222. In some embodiments, by providing the grooves opposite to the sensitive thin film resistors, the strain and stress of the substrate 1221 can be mainly concentrated in the groove area when deformation occurs, and transmitted to the sensitive thin film resistors opposite to the grooves. When the user's body acts on the contact surface 111, the substrate 1221 can produce a corresponding deformation in response to the pressure exerted on the contact surface 111, and transmit the deformation to the resistive film layer 1224, so as to cause the sensitive thin film resistor to undergo tensile deformation, so that the resistance value of the sensitive thin film resistor changes, thereby causing the read voltage (Vout) to change accordingly. In some embodiments, the processor 130 may determine the current usage state of the acoustic output device 100 based on the readout voltage (Vout) and a mapping relationship between the readout voltage (Vout) and the usage state obtained from experimental data. In some embodiments, the processor 130 may process the readout voltage (Vout) based on a machine learning algorithm to determine the current usage state of the acoustic output device 100. In some embodiments, the ratio of the depth of the groove 1225 to the thickness of the substrate 1221 is within a range of 1 / 4 to 3 / 4. In some embodiments, the groove 1225 may include a micro-gap provided on the surface where the substrate 1221 connects to the first circuit board 1222.

[0092] FIG9 is a schematic structural diagram of an acoustic output device shown in other embodiments of this specification.

[0093] 9 , in some embodiments, the contact detection sensor 120 may further include a second circuit board 1226 , one side of which is connected to the side of the substrate 1221 facing away from the first circuit board 1222 , and a capacitive electrode 1227 is provided on the other side of the second circuit board 1226 . In some embodiments, the second circuit board 1226 may include multiple capacitive electrodes 1227 , which may be arranged in an array. In some embodiments, the capacitive electrode 1227 may be connected to the contact area of ​​the housing 113 . When human skin (such as a user's face or finger) contacts the contact area of ​​the housing 113 , the human skin may act as a conductor to affect the capacitance of the capacitive electrode 1227 , thereby enabling contact detection based on the capacitance of the capacitive electrode 1227 . By providing the capacitive electrode 1227 , the source of the pressure applied to the contact area of ​​the housing 113 can be determined, thereby eliminating false recognition caused by pressure response generated by squeezing and colliding with other objects such as cloth, keys, and plastic when the acoustic output device 100 is placed in a bag or pocket.

[0094] In some embodiments, by combining the capacitive electrode 1227 with the resistive pressure sensor shown in Figure 8 to jointly detect the current usage status of the acoustic output device 100, it is possible to avoid misidentification caused by collision and compression of the acoustic output device 100 with other objects when using the resistive pressure sensor alone. At the same time, it is also possible to avoid misidentification caused by external environmental interference such as water and sweat when using the capacitive electrode 1227 alone, thereby eliminating most interference and greatly improving the recognition accuracy of the usage status of the acoustic output device 100.

[0095] In some embodiments, when the change in the capacitance value of the capacitor electrode 1227 and the change in the resistance value of the resistive film layer 1224 in the resistive pressure sensor simultaneously reach a threshold, it can be determined that the acoustic output device 100 is currently in a normal wearing state. The situation where only the capacitance value of the capacitor electrode 1227 changes or only the resistance value of the resistive film layer 1224 changes to reach the threshold can be excluded.

[0096] In some embodiments, the capacitive electrode 1227 can be combined with the contact detection sensor shown in FIG7 to determine the current usage status of the acoustic output device 100. The capacitive electrode 1227 can be equivalent to a capacitive sensor, and the contact detection sensor shown in FIG7 can be equivalent to a resistive sensor. Specifically, in some embodiments, a preliminary judgment can be made based on the capacitive electrode 1227 to exclude the possibility that the acoustic output device 100 is squeezed by other objects, and then the contact detection sensor shown in FIG7 can be used to determine whether the acoustic output device is currently in a normal wearing state.

[0097] Similarly, in some embodiments, the contact detection sensor shown in FIG6 may be combined with the resistive pressure sensor shown in FIG7 to determine the current usage status of the acoustic output device 100. In some embodiments, the aforementioned capacitive electrode 1227 may also be combined with an infrared sensor to determine the current usage status of the acoustic output device 100.

[0098] FIG10 is a schematic structural diagram of an acoustic output device shown in other embodiments of this specification.

[0099] 10 , when the acoustic output unit is a bone conduction speaker, the acoustic output unit may include a housing 113, a vibration unit 114, and a contact detection sensor 120. The vibration unit 114 and the contact detection sensor 120 are located within a housing cavity of the housing 113. The contact detection sensor 120 is located on the inner surface of a contact surface 111 of the housing 113 for contact with the human body. The vibration unit 114 may be elastically connected to the housing 113 via a vibration transmission piece 115, which may be used to transmit the vibration generated by the vibration unit 114 to the housing 113. In some embodiments, the vibration unit 114 may be disposed on a side of the vibration transmission piece 115 facing away from the contact detection sensor 120. In some embodiments, considering that the vibration unit 114 may cause the vibration plate 115 to deform during vibration, causing the vibration plate 115 to contact the contact detection sensor 120, thereby affecting the detection results of the contact detection sensor 120 and possibly affecting the resonant frequency of the vibration unit 114, in some embodiments, to prevent the vibration unit 114 or the vibration plate 115 from contacting the contact detection sensor 120 during vibration, the distance d1 between the contact detection sensor 120 and the vibration plate 115 in the vibration direction of the vibration unit 114 (e.g., the z-z' direction shown in FIG. 10 ) can be greater than 300 μm. For example, in some embodiments, the distance d1 between the contact detection sensor 120 and the vibration plate 115 in the vibration direction of the vibration unit 114 can be 300 μm to 5000 μm. In some embodiments, the distance d1 between the contact detection sensor 120 and the vibration plate 115 in the vibration direction of the vibration unit 114 can be 1000 μm to 5000 μm. In some embodiments, a distance d1 between the contact detection sensor 120 and the vibration sensor 115 in the vibration direction of the vibration unit 114 may be 1000 um to 4000 um.

[0100] FIG11 is a schematic structural diagram of an acoustic output device shown in other embodiments of this specification.

[0101] In some embodiments, the vibration plate 115 may include a central region 1151, an edge region 1153, and a plurality of rods 1152 connecting the central region 1151 and the edge region 1153. The edge region 1153 is connected to the housing 113, and the vibration unit 114 may be connected to the central region 1151. Referring to FIG. 11 , in some embodiments, the vibration plate 115 may include a hollow region (e.g., regions A, B, C, and D). The hollow region may be understood as the space formed between adjacent rods 1152, the outer edge of the central region 1151, and the inner edge of the edge region 1153. In some embodiments, to prevent the vibration unit 114 or the vibration plate 115 from contacting the contact detection sensor 120 during vibration, the contact detection sensor 120 may be disposed within the hollow region of the vibration plate 115. Specifically, the projection of the contact detection sensor 120 along the vibration direction of the vibration unit is within the hollow region of the vibration plate 115.

[0102] FIG. 12 is a schematic structural diagram of a contact detection sensor of an acoustic output device shown in other embodiments of this specification.

[0103] In some embodiments, the acoustic output device 100 may include a diaphragm 116, which may be connected to a transducer 118. The transducer 118 drives the diaphragm 116 to vibrate based on an electrical signal, which in turn drives the air to vibrate, thereby generating air-conducted sound waves. Referring to FIG12 , in some embodiments, the housing 113 may include a sound outlet 117, through which the air driven by the diaphragm 116 can be transmitted to the outside. In some embodiments, the sound outlet 117 may be located on a side wall of the housing 113 adjacent to the contact surface 111. When a user wears the acoustic output device 100, the sound outlet 117 may face the opening of the user's ear canal so that the user can receive the air-conducted sound waves. It should be noted that the structure shown in FIG12 is merely illustrative. In other embodiments, the sound outlet 117 may be located elsewhere on the housing 113. For example, in some embodiments, the sound outlet 117 may be located on the outer side 112.

[0104] Similarly, in some embodiments, in order to prevent the diaphragm 116 from interfering with the detection results of the contact detection sensor 120 during vibration, the distance d2 between the contact detection sensor 120 and the diaphragm 116 in the vibration direction of the diaphragm 116 (for example, the zz' direction in Figure 12) can be made greater than 300um.

[0105] FIG13 is a schematic structural diagram of an acoustic output device shown in other embodiments of this specification.

[0106] Considering that although arranging the contact detection sensor 120 on the inner surface of the shell 113 can improve the sealing and waterproof performance of the acoustic output device 100, the sensitivity of the contact detection sensor 120 is lost, therefore, referring to Figure 13, in some embodiments, in order to improve the sensitivity of the contact detection sensor 120 while ensuring the sealing and waterproof performance of the acoustic output device 100, the contact detection sensor 120 can be arranged on the outer surface of the contact area (such as the contact surface 111) of the shell 113, and then wirelessly coupled with the contact detection sensor 120 through a coupling circuit arranged on the inner surface of the contact area, so that the electrical signal generated by the contact detection sensor 120 is transmitted to the processing chip 220 located inside the shell 113.

[0107] 13 , in some embodiments, the coupling circuit may include a first inductor element L1, a first capacitor element C1, and a processing chip 220; the contact detection sensor 120 disposed on the outer surface of the contact area of ​​the housing 113 may include a second capacitor element Cs and a second inductor element Ls; the first inductor element L1 and the first capacitor element C1 are connected in parallel to form a first loop; the second inductor element Ls and the second capacitor element Cs are connected in parallel to form a second loop; and the processing chip 220 may be used to read the resonant frequency after the first loop and the second loop are coupled.

[0108] Referring to Figure 13 , in some embodiments, the coupling circuit may include a third circuit board 1231. One side of the third circuit board 1231 is connected to the inner surface of the contact region of the housing 113, for example, by adhesive bonding. In some embodiments, the first inductor L1, the first capacitor C1, and the processing chip 220 may be located on a side of the third circuit board 1231 facing away from the contact region.

[0109] In some embodiments, the second capacitor element Cs and the second inductor element Ls are located on the outer surface of the contact area of ​​the housing 113. The second inductor element Ls is positioned directly opposite the first inductor element L1, which is positioned on the inner surface of the contact area of ​​the housing 113. This ensures good coupling between the first inductor element L1 and the second inductor element Ls. Specifically, the second inductor element Ls and the first inductor element L1 are positioned on the inner and outer sides of the contact area of ​​the housing 113, and the line connecting the second inductor element Ls and the first inductor element L1 is substantially perpendicular to the plane of the contact area.

[0110] The second capacitive element Cs may be a pressure-sensitive capacitor. Specifically, the capacitance of the second capacitive element Cs may vary with the applied pressure. In some embodiments, by disposing the second capacitive element Cs on the outer surface of the contact area of ​​the housing 113, the second capacitive element Cs may better detect the contact pressure between the human skin 300 and the contact area of ​​the housing 113, thereby increasing the sensitivity of the contact detection sensor 120.

[0111] 14 , the first inductor element L1 and the second inductor element Ls can be wirelessly coupled. When the capacitance value of the second capacitive element Cs changes based on the contact pressure between the human skin 300 and the housing 113, the circuit parameters (e.g., capacitance data, voltage data, and / or current data) in the second loop can be transmitted to the first loop, causing the circuit parameters in the first loop to change accordingly. Furthermore, the processing chip 220 can read the resonant frequency of the coupled first and second loops based on the changes in the circuit parameters.

[0112] In some embodiments, the resonant frequency of the first loop can be expressed as:

[0113] The resonant frequency of the second loop can be expressed as:

[0114] The resonant frequency after coupling the first loop and the second loop can be expressed as:

[0115] Wherein, L1 is the inductance value of the first inductor element, Ls is the inductance value of the second inductor element, C1 is the capacitance value of the first capacitor element, Cs is the capacitance value of the second capacitor element, and k is the coupling coefficient between the inductors L1 and Ls.

[0116] 19. The acoustic output device according to claim 17, wherein the contact detection device comprises a fourth circuit board, one side of the fourth circuit board is connected to the outer surface of the contact area, and the second capacitance element and the second inductance element are located on a side of the fourth circuit board away from the contact area.

[0117] Continuing with FIG. 13 , in some embodiments, the contact detection sensor 120 may include a fourth circuit board 1232. One side of the fourth circuit board 1232 is connected to the outer surface of the contact area of ​​the housing 113. The second capacitive element Cs and the second inductive element Ls may be disposed on a side of the fourth circuit board 1232 facing away from the contact area. When human skin 300 contacts the contact area of ​​the housing 113, the capacitance of the second capacitive element Cs may change in response to changes in pressure between the human skin 300 and the contact area of ​​the housing 113.

[0118] Similar to the aforementioned first circuit board 1222 and second circuit board 1226 , in some embodiments, the third circuit board 1231 and the fourth circuit board 1232 may also include flexible printed circuits (FPCs).

[0119] In some embodiments, the aforementioned wireless coupling may include photoelectric coupling. Specifically, in some embodiments, at least a portion of the contact area of ​​the shell 113 may be made of a transparent material (such as glass or transparent plastic). The contact detection sensor 120 arranged on the outer surface of the contact area of ​​the shell 113 may include a light-emitting diode, which may be arranged on the transparent part of the contact area. The coupling circuit arranged on the inner surface of the contact area of ​​the shell 113 may include a photosensitive element, which is arranged on the transparent part of the contact area. The signal detected by the contact detection sensor 120 may be transmitted to the coupling circuit arranged on the inner surface of the contact area of ​​the shell 113 through the coupling relationship between the light-emitting diode and the photosensitive element. In some embodiments, power supplies may be provided on the inner surface and outer surface of the contact area, respectively, to power the light-emitting diode and the photosensitive element.

[0120] 13 , in some embodiments, a second protective layer 1233 may be provided on the outer surface of the contact area of ​​the housing 113. The second protective layer 1233 may cover the contact detection sensor 120 located on the outer surface of the contact area of ​​the housing 113. In some embodiments, the second protective layer 1233 may be made of silicone or other skin-friendly, flexible materials, such as TESiV (thermoplastic elastomer).

[0121] FIG15 is a schematic structural diagram of an acoustic output device shown in some embodiments of this specification.

[0122] 15 , in some embodiments, the acoustic output device 100 may include an ear hook 141 , one end of which is connected to the acoustic output unit 110 . When a user uses the acoustic output device 100 , the user may hang the acoustic output unit 110 near the user's ear via the ear hook 141 .

[0123] As shown in FIG15 , in some embodiments, the acoustic output device 100 may include a single-ear hanging headphone, which may be a bone conduction headphone, an air conduction headphone, or a combined bone and air conduction headphone. In some embodiments, the acoustic output device 100 may include various types, such as electromagnetic (e.g., dynamic coil, moving iron, etc.), piezoelectric, inverse piezoelectric, electrostatic, etc. The contact detection sensor 120 may be disposed at a contact area of ​​the housing of the acoustic output unit 110 (e.g., the inner or outer surface of the contact surface 111). When a user wears the acoustic output device 100, the contact area may contact the user's skin, and the contact detection sensor 120 may generate a responsive electrical signal in response to the contact area contacting the user's skin.

[0124] FIG16 is a schematic structural diagram of an acoustic output device shown in other embodiments of this specification.

[0125] 16 , in some embodiments, the acoustic output device 100 may include a back-hook earphone, which may include an ear hook 141, a back hook 142, and an acoustic output unit 110. The ear hook 141 may cooperate with the user's auricle to allow the acoustic output device 100 to be hung on the user's ear. The back hook 142 may be placed behind the user's neck or head (for example, when the user is wearing the acoustic output device 100 normally, the back hook 142 may be fixed behind the user's head. When the user is not wearing the acoustic output device 100 (i.e., the acoustic output device 100 is not in normal wearing), the user may hang the acoustic output device 100 around the neck, in which case the back hook 142 may be fixed behind the user's neck). The ear hook 141 and the back hook 142 may cooperate to provide a clamping force to secure the acoustic output unit 110 to the user's head or ear, thereby ensuring that the acoustic output device 100 is stably hung on the user's ear and is not likely to fall off.

[0126] In some embodiments, the acoustic output unit 110 may include a first acoustic output unit 1101 and a second acoustic output unit, and the ear hook 141 may include a first ear hook 1411 and a second ear hook 1412, wherein the first ear hook 1411 is connected to one end of the first acoustic output unit 1101 and the rear hook 142, and the second ear hook 1412 is connected to the other end of the second acoustic output unit 1102 and the rear hook 142. The first ear hook 1411 can be used to hang the first acoustic output unit 1101 near one ear of the user, and the second ear hook 1412 can be used to hang the second acoustic output unit 1102 near the other ear of the user. Referring to Figure 16, the housings of the first acoustic output unit 1101 and the second acoustic output unit 1102 may include a contact surface 111, which can contact the human skin during the user's wearing process. In some embodiments, the contact detection sensor 120 can be provided on the inner surface or outer surface of the contact surface 111.

[0127] 16 , in some embodiments, an earphone compartment 150 may be included between the ear hook 141 and the back hook 142. In some embodiments, the earphone compartment 150 may be used to store or accommodate one or more components of the acoustic output device 100 (e.g., a processor, a control circuit, a Bluetooth module, a battery, etc.).

[0128] As shown in Figure 16, in some embodiments, the aforementioned flexible cavity-based pressure sensor 160 can be set in the middle part of the back hook 142. It will be understood that the structure shown in Figure 16 is only an example. In some other embodiments, the flexible cavity-based pressure sensor 160 can be set in other locations that can be deformed or come into contact with the user during use. For example, the flexible cavity-based pressure sensor 160 can be located on the inner side of the acoustic output unit 110 or the inner side of the earphone compartment 150. For another example, the flexible cavity-based pressure sensor 160 can be located on the ear hook 141 (for example, the first ear hook 1411 and the second ear hook 1412). Similarly, in some embodiments, when an infrared sensor is used to control the working state of the aforementioned first piezoelectric element 1211, the infrared sensor can be set on the inner side of the back hook 142, the inner side of the acoustic output unit 110, the inner side of the earphone compartment 150, or other locations that can detect the human body. The inner side of the acoustic output unit 110 and the inner side of the earphone compartment 150 can refer to the side close to the human skin during the user's wearing.

[0129] FIG17A is a schematic diagram of an exemplary acoustic output device according to some embodiments of the present specification in a freely placed state. FIG17B is a schematic diagram of an exemplary acoustic output device according to some embodiments of the present specification in a normally worn state. FIG17C is a schematic diagram of an exemplary acoustic output device according to some embodiments of the present specification in an abnormally worn state.

[0130] 17A to 17C , in some embodiments, a contact detection sensor 120 may be provided at a contact area of ​​the housing of at least one acoustic output unit 110 (e.g., the inner or outer surface of the contact surface 111 ) to identify whether the acoustic output unit 110 is in contact with the user. As shown in FIG17A , when the contact signal detected by the contact detection sensor 120 indicates that the acoustic output unit 110 is not in contact with the user, a first contact signal may be output. As shown in FIG17B and FIG17C , when the contact signal detected by the contact detection sensor 120 indicates that the acoustic output unit 110 is in contact with the user, a second contact signal may be output. The first contact signal and the second contact signal may correspond to different signal parameters, which may include but are not limited to resonant frequency, capacitance, resistance, voltage, current, etc.

[0131] In some embodiments, the contact detection sensor 120 may also include an infrared sensor. When the contact detection sensor 120 includes an infrared sensor, it can detect the distance between the acoustic output unit 110 and the human skin. When the distance is greater than a preset distance threshold, it can be determined that the user is not in contact with the acoustic output unit 110. Conversely, when the distance is less than the preset distance threshold, it can be determined that the user is in contact with the acoustic output unit 110.

[0132] In some embodiments, the processor 130 may issue corresponding control instructions in response to a contact signal detected by the contact detection sensor 120. Specifically, when the contact signal detected by the contact detection sensor 120 indicates that the acoustic output device 100 is in a normal wearing state (as shown in FIG17B ), the processor 130 may control the acoustic output device 100 to enter a wake-up state, automatically connect to Bluetooth, or play music. Conversely, when the contact signal detected by the contact detection sensor 120 indicates that the acoustic output device 100 is in an abnormal wearing state (as shown in FIG17C ) or a placed state (as shown in FIG17A ), the processor 130 may control the acoustic output device 100 to automatically stop playing music or disconnect the Bluetooth connection, and enter standby mode after this state persists for a period of time (e.g., 10 seconds, 15 seconds, etc.).

[0133] The beneficial effects that may be brought about by the embodiments of this specification include but are not limited to: (1) In some embodiments of this specification, by arranging the contact detection sensor on the inner surface of the contact area of ​​the shell, it is easy to connect the wires and avoid the need for punching operations, thereby avoiding damage to the integrated design of the shell, thereby improving the sealing performance and waterproof performance of the acoustic output device to a certain extent; (2) In some embodiments of this specification, by using a resistive pressure sensor to realize the wearing detection function, and directly attaching the resistive pressure sensor to the inner surface of the contact area of ​​the shell of the acoustic output device, it is possible to effectively shield the influence of external environment such as water and sweat, thereby improving the recognition accuracy to a certain extent; (3) In some embodiments of this specification, by arranging the contact detection sensor on the outer surface of the contact area of ​​the shell, then Then, a coupling circuit provided on the inner surface of the contact area is wirelessly coupled with the contact detection sensor, thereby transmitting the electrical signal generated by the contact detection sensor to the processing chip located inside the shell, thereby ensuring the sealing performance and waterproof performance of the acoustic output device while improving the sensitivity of the contact detection sensor; (4) In some embodiments of the present specification, by combining the capacitor electrode with the resistive pressure sensor to jointly detect the current use status of the acoustic output device, it is possible to avoid misidentification caused by collision and compression of the acoustic output device with other objects when the resistive pressure sensor is used alone, and it is also possible to avoid misidentification caused by external environmental interference such as water and sweat when the capacitor electrode is used alone, thereby eliminating most interference and greatly improving the recognition accuracy of the use status of the acoustic output device.

[0134] It should be noted that different embodiments may produce different beneficial effects. In different embodiments, the beneficial effects that may be produced may be any one or a combination of the above, or any other possible beneficial effects.

[0135] While the basic concepts have been described above, it will be apparent to those skilled in the art that the detailed disclosure is merely illustrative and does not limit this specification. Although not explicitly stated herein, various modifications, improvements, and revisions to this specification may be made by those skilled in the art. Such modifications, improvements, and revisions are suggested in this specification and remain within the spirit and scope of the exemplary embodiments of this specification.

Claims

1. An acoustic output device, comprising: an acoustic output unit, comprising a vibration unit and a housing, the housing comprising at least a contact area that contacts a user's facial area; a contact detection sensor, the contact detection sensor being located at the contact area; as well as A processor is configured to determine whether the user is wearing the acoustic output device based on an electrical signal generated when the contact detection sensor contacts the user's facial area.

2. The acoustic output device according to claim 1, wherein: The contact detection sensor includes an inductor, a piezoelectric element and a processing chip. The piezoelectric element is connected to the inner surface of the contact area. The piezoelectric element generates vibration based on a preset voltage. The inductor and the piezoelectric element are connected in parallel to form a loop. The processing chip is used to read the resonant frequency of the loop.

3. The acoustic output device according to claim 2, wherein: The contact detection sensor further includes a capacitive element connected in parallel with the piezoelectric element.

4. The acoustic output device according to claim 1, wherein: The contact detection sensor includes a first piezoelectric element and a receiving element which are stacked together. The side of the first piezoelectric element facing away from the receiving element is connected to the inner surface of the contact area. The first piezoelectric element generates vibration based on a preset voltage. When a user touches the contact area, the vibration state of the first piezoelectric element changes.

5. The acoustic output device according to claim 4, wherein: The resonance frequency of the first piezoelectric element is not less than 20 kHz.

6. The acoustic output device according to claim 4, wherein: The receiving element includes an air conduction microphone or a second piezoelectric element.

7. The acoustic output device according to any one of claims 4 to 6, wherein: The contact detection sensor further includes a substrate, and the first piezoelectric element, the receiving element and the substrate are stacked.

8. The acoustic output device according to claim 1, wherein: The contact detection sensor comprises a stacked substrate, a first circuit board, and a resistive film layer. The substrate is connected to the inner surface of the contact area. The contact detection sensor deforms in response to the deformation of the contact side wall and converts the deformation into an electrical signal.

9. The acoustic output device according to claim 8, wherein: The resistance film layer includes at least two sensitive film resistors and at least two fixed film resistors, and the at least two sensitive film resistors and the at least two fixed film resistors are electrically connected to form a bridge circuit.

10. The acoustic output device according to claim 9, wherein: A surface of the substrate connected to the first circuit board is provided with a plurality of grooves, and the plurality of grooves include at least two grooves respectively facing the at least two sensitive thin film resistors.

11. The acoustic output device according to any one of claims 8 to 10, wherein the contact detection sensor comprises a second circuit board, one side of the second circuit board is connected to a side of the substrate facing away from the first circuit board, and a capacitive electrode is disposed on the other side of the second circuit board.

12. The acoustic output device according to any one of claims 1 to 11, wherein: The vibration unit is elastically connected to the shell through a vibration transmission piece, and along the vibration direction of the vibration unit, the distance between the contact detection sensor and the vibration transmission piece is greater than 300 um.

13. The acoustic output device according to any one of claims 1 to 11, wherein: The vibration unit is elastically connected to the shell through a vibration transmission sheet, the vibration transmission sheet includes a hollow area, and the projection of the contact detection sensor along the vibration direction of the vibration unit is within the hollow area.

14. The acoustic output device according to claim 1, further comprising a coupling circuit, wherein: The contact detection sensor is located on the outer surface of the contact area, the coupling circuit is located on the inner surface of the contact area, and the coupling circuit is wirelessly coupled to the contact detection sensor.

15. The acoustic output device according to claim 14, wherein the coupling circuit comprises a first inductor element, a first capacitor element and a processing chip, and the contact detection sensor device comprises a second capacitor element and a second inductor element, wherein: The first inductance element and the first capacitance element are connected in parallel to form a first loop, the second inductance element and the second capacitance element are connected in parallel to form a second loop, and the processing chip is used to read out the resonant frequency of the first loop and the second loop after coupling.

16. The acoustic output device according to claim 15, wherein the coupling circuit comprises a third circuit board, one side of the third circuit board is connected to the inner surface of the contact area, and the first inductor element, the first capacitive element and the processing chip are located on a side of the third circuit board away from the contact area. 17 . The acoustic output device according to claim 15 , wherein the second capacitive element and the second inductive element are located on an outer surface of the contact area, and the second inductive element is disposed opposite to the first inductive element. 18 . The acoustic output device according to claim 17 , wherein the second capacitive element is a pressure-sensitive capacitor, and a capacitance value of the second capacitive element changes with a change in pressure.

19. The acoustic output device according to claim 17, wherein the contact detection device comprises a fourth circuit board, one side of the fourth circuit board is connected to the outer surface of the contact area, and the second capacitive element and the second inductive element are located on a side of the fourth circuit board away from the contact area. 20 . The acoustic output device according to claim 14 , wherein an outer surface of the contact area of ​​the housing is provided with a protective layer, and the protective layer covers the contact detection sensor.

21. The acoustic output device according to any one of claims 1 to 20, wherein the processor is further configured to issue a control instruction in response to a user wearing the acoustic output device, wherein the control instruction changes a working state of the acoustic output device.

22. The acoustic output device according to any one of claims 1 to 21, further comprising an ear hook, one end of the ear hook being connected to the acoustic output unit, the ear hook positioning the acoustic output unit near an ear of a user.

23. The acoustic output device according to claim 22, further comprising a rear hook, the ear hook comprising a first ear hook and a second ear hook, the acoustic output unit comprising a first acoustic output unit and a second acoustic output unit, the first ear hook being connected to the first acoustic output unit and the rear hook, the second ear hook being connected to the second acoustic output unit and the rear hook, the first ear hook hanging the first acoustic output unit near one ear of the user, the second ear hook hanging the second acoustic output unit near the other ear of the user, and the first ear hook and the second ear hook being connected via the rear hook.

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