Capacitive in-ear detection on earpiece

Abstract

The invention relates to capacitive in-ear detection on an earpiece. An earpiece includes a device housing defining an internal cavity within the device housing; an acoustic aperture formed through the device housing and having an opening at an outer surface of the device housing; an audio driver disposed within the device housing and aligned to emit sound through the acoustic aperture; a plurality of capacitive pixels disposed within the internal cavity, where at least two of the capacitive pixels are disposed radially around the acoustic aperture and spaced apart from each other by at least 90 degrees; and a sensor control circuit disposed within the interior cavity and operably coupled to drive the plurality of capacitive pixels at a predetermined frequency to read out a capacitance at each of the plurality of capacitive pixels and determine whether the earpiece is within the user's ear.

Description

[0001] Cross-references to other applications

[0002] This application claims priority to U.S. Provisional Application No. 63 / 539,899, filed on September 22, 2023, entitled “CAPACITIVE IN EAR DETECT ON EARPHONES,” and U.S. Non-Provisional Application No. 18 / 737,837, filed on June 7, 2024, entitled “CAPACITIVE IN EAR DETECT ON EARPHONES,” which applications are incorporated herein by reference in their entirety for all purposes. Background Art

[0003] Portable listening devices, such as headphones, can be used with a variety of electronic devices, including portable media players, smart phones, tablet computers, laptop computers, stereo systems, etc. Portable listening devices historically include one or more small speakers configured to be placed on, in, or near the ears of a user, structural components to hold the speakers in place, and a cable to electrically connect the portable listening device to an audio source.

[0004] One growing trend is the increasing popularity of small wireless earphones (referred to herein as "wireless earpieces") that fit within a user's ear. Wireless earpieces do not include a cable between an audio source and the earpiece. Instead, the wireless earpiece receives an audio data stream wirelessly from a wireless audio source. Such wireless earpieces require batteries to operate the circuitry within the earpiece, including the speaker and the wireless circuitry.

[0005] While wireless earpieces have many advantages over wired portable listening devices and have become very popular among consumers, improved wireless earpieces are desired. Summary of the invention

[0006] The present disclosure describes various embodiments of earpiece (including wireless earpiece), and this earpiece can enable user to experience high-end acoustic performance and pleasant positive user experience.Some embodiments include multiple capacitive pixels, and these multiple capacitive pixels are strategically positioned along the outer surface of the part of the earpiece housing adapted in the user's ear.Capacitive pixels can provide signals to controller or other circuits, and this controller or other circuits can detect when the earpiece is positioned in the user's ear and adjust the operating mode of the earpiece accordingly subsequently.Therefore, for example, when controller or other circuits detect that the earpiece is removed from the user's ear, the earpiece can be placed in low power mode, and this low power mode requires less energy than normal (activity) operating mode.In this way, low power mode saves battery power, thereby improves the user experience of the earpiece by allowing the earpiece to keep operating time longer and / or charging frequency less than the situation that might originally be needed when single charging.

[0007] An earpiece according to some embodiments includes: a device housing defining an internal cavity within the device housing; an acoustic orifice formed through the device housing and having an opening at an outer surface of the device housing; an audio driver disposed within the device housing and aligned to emit sound through the acoustic orifice; a plurality of capacitive pixels disposed within the internal cavity, wherein at least two of the capacitive pixels are radially disposed around the acoustic orifice and spaced at least 90 degrees apart from each other; and a sensor control circuit disposed within the internal cavity and operably coupled to drive the plurality of capacitive pixels at a predetermined frequency to read the capacitance at each of the plurality of capacitive pixels and determine whether the earpiece is within the user's ear.

[0008] In some embodiments, the earpiece includes: a device housing including a housing wall that defines both an outer surface of the earpiece and an inner surface of the device housing; an acoustic orifice formed through the device housing and having an opening at the outer surface of the device housing; an audio driver disposed within the device housing and aligned to emit sound through the acoustic orifice; a plurality of recessed areas formed in the housing wall; a plurality of capacitive pixels disposed within the device housing, wherein each of the plurality of capacitive pixels is disposed within a unique recessed area of ​​the plurality of recessed areas, and wherein at least two of the capacitive pixels are radially disposed around the acoustic orifice and spaced at least 120 degrees apart from each other; and a sensor control circuit disposed within the internal cavity and operably coupled to drive the plurality of capacitive pixels at a predetermined frequency to read the capacitance at each of the plurality of capacitive pixels and determine whether the earpiece is within the user's ear based on an algorithm.

[0009] According to some embodiments, a portable acoustic device is provided, comprising: a device housing, the device housing comprising a speaker housing portion and a rod portion extending away from the speaker housing portion, wherein the speaker housing portion and the rod portion combine to define an internal cavity within the device housing; an acoustic orifice formed through a wall of the speaker housing portion and having an opening at an outer surface of the device housing; an audio driver disposed within the speaker housing portion and aligned to emit sound through the acoustic orifice; a plurality of capacitive pixels disposed within the internal cavity, wherein at least two of the capacitive pixels are radially disposed around the acoustic orifice and spaced at least 90 degrees apart from each other; and a sensor control circuit disposed within the internal cavity and operably coupled to drive the plurality of capacitive pixels at a predetermined frequency to read the capacitance at each of the plurality of capacitive pixels and determine whether the earpiece is within the user's ear based on an algorithm.

[0010] In various specific implementations, the earpiece according to the embodiments disclosed herein may also include one or more of the following. The device housing may include a housing wall that defines both the outer surface of the earpiece and the inner surface of the device housing. The earpiece may also include a plurality of recessed areas formed in the housing wall, and each of the plurality of capacitive pixels may be disposed in a unique recessed area in the plurality of recessed areas. Each capacitive pixel may have a thickness of 500 microns or less, or may have a thickness of 100 microns or less. Each capacitive sensor may include a stack of layers, the stack comprising: a first conductive layer, the first conductive layer including an active area and a guard ring surrounding the active area and spaced apart from the active area; a conductive shielding layer; and a dielectric layer disposed between the first conductive layer and the conductive shielding layer. The sensor control circuit may also be configured to apply a pulse voltage to the guard ring and the conductive shielding layer at the same frequency and time as the driving capacitive pixel. The sensor control circuit can be configured to drive the plurality of pixels according to a multi-step process in which the capacitance of each capacitive pixel is measured at a point in time when the guard ring and the conductive shielding layer are grounded, and then measured at a second point in time when the guard ring and the conductive shielding layer are pulsed with a signal that simulates a sensing pulse applied to the sensing area. At least two of the plurality of capacitive pixels are radially arranged around the acoustic aperture and spaced at least 120 degrees apart from each other. The diameter of the sensing area of ​​each of the plurality of capacitive pixels can be 4 mm or less. The sensor control circuit can determine whether the earpiece is in the ear of the user based on a predetermined in-ear detection algorithm, the predetermined in-ear detection algorithm comprising determining whether the capacitance values ​​of the plurality of measurements of two or more pixels are greater than or less than a predetermined threshold.

[0011] To better understand the essence and advantages of the present invention, reference should be made to the following description and accompanying drawings. However, it should be understood that each of the accompanying drawings is provided for illustrative purposes only and is not intended to be a definition of the limitations of the scope of the present invention. Moreover, as a general rule, and unless it is obvious to the contrary in the description, if the same reference numeral is used for elements in different figures, the elements are generally the same or at least similar in function or purpose. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 is a simplified illustration of an exemplary portable electronic listening device system having a host device configured as a smart phone, a housing, and a pair of wireless listening devices configured as handsets according to some embodiments;

[0013] Figure 2 is a simplified block diagram of various components of a portable wireless listening system according to some embodiments;

[0014] FIG. 3A to FIG. 3C is a simplified illustration of a portable wireless handset according to some embodiments;

[0015] Figure 4 yes FIG. 3A to FIG. 3C A simplified front perspective view of the earpiece described in without its ear tip;

[0016] Figure 5A and Figure 5B is a simplified cross-sectional view of a portion of an earbud housing according to some embodiments;

[0017] Fig. 6A is a simplified top plan view of a capacitive pixel according to some embodiments;

[0018] Figure 6B is positioned within a slot formed in the earpiece housing according to some embodiments Fig. 6A A simplified cross-sectional view of a capacitive pixel shown in ;

[0019] Figure 7 is a graph illustrating turn-on and turn-off points of a capacitive pixel according to certain embodiments;

[0020] Fig. 8A and Figure 8B is a simplified cross-sectional view schematic diagram of a capacitive pixel according to some embodiments; and

[0021] Fig. 9A and Fig. 9B is a simplified cross-sectional view schematic diagram of a capacitive pixel according to some embodiments. DETAILED DESCRIPTION

[0022] Described herein is the embodiment of earpiece (comprising wireless earpiece), and this earpiece can make user can experience high-end acoustic performance and pleasant positive user experience.Some embodiments include multiple capacitance pixels, and these multiple capacitance pixels are strategically positioned along the outer surface of the part of earpiece shell that is adapted in user's ear.Capacitance pixel can be very thin, thus occupies minimum space in earpiece shell.Pixel can detect when earpiece is positioned in user's ear and signal is provided to controller or other circuit, and this controller or other circuit can adjust the operating mode of earpiece accordingly subsequently.Therefore, for example, when controller or or other circuit detects that earpiece is not in user's ear, controller or other circuit can activate the low power mode of earpiece, and this low power mode uses less energy than normal (activity) operating mode.In this way, low power mode saves battery power, thereby allows earpiece to keep operating time longer and / or less than the situation charging frequency that may be needed originally when single charge.

[0023] definition

[0024] As used herein, the term "portable listening device" includes any portable device that is configured to be worn by a user and positioned so that a speaker of the portable listening device is adjacent to or in the ear of the user. A "portable wireless listening device" is a portable listening device that is capable of receiving an audio data stream from a second device and / or transmitting an audio data stream to a second device using, for example, a wireless communication protocol without requiring a wire connecting the portable wireless listening device to the second device.

[0025] Earphones are one type of portable listening device, headphones (a combination of earphones and an attached microphone) are another type of portable listening device, and hearing aids (in-ear devices designed to enhance the sound from the surrounding environment to improve the user's hearing) are still additional types of portable listening devices. The term "earphones" refers to a pair of small portable listening devices designed to be worn on or around the user's head. They convert electrical signals into corresponding sounds that can be heard by the user. Earphones include traditional earphones that are worn over the user's head and include left and right earmuffs connected to each other by a headband, and in-ear earphones (very small earphones designed to fit directly in the user's ears). Traditional earphones include both: over-ear headphones (sometimes called circumaural or full-size headphones), which have ear pads that completely enclose the user's ears; and over-ear headphones (sometimes also called on-ear headphones), which have ear pads that can be pressed against the user's ears instead of surrounding them.

[0026] Earpieces are a type of headset and a portable listening device. The term "earpiece" (also known as an over-ear headset) includes both small earphones (sometimes called "earbuds") that fit inside the user's outer ear so as to face the ear canal without being inserted into the ear canal, and in-ear headphones (sometimes called canal headphones) that are inserted into the ear canal itself. However, the term "earbud" is used inconsistently in the industry and is often used to refer to any type of earphone that fits inside the user's ear. Therefore, as used herein, the terms "earbud" and "earpiece" are used interchangeably and may refer to both earpieces that are inserted into the ear canal and earpieces that face the ear canal without being inserted therein.

[0027] As used herein, the term "ear tip" (also referred to as ear mold) includes a pre-formed, post-formed, or custom-molded sound guide structure that fits at least partially within the ear canal. Ear tips can be formed to have a comfortable fit that can be worn for a long period of time. They can have different sizes and shapes to achieve a better seal with the user's ear canal and / or ear cavity.

[0028] In order to better understand and appreciate the earpiece according to the embodiments described herein, the following is a description of the Figure 1 Provide a brief description of the use case for this type of handset.

[0029] Example Wireless Listening System

[0030] Figure 1 is an example of a wireless listening system 100 according to some embodiments. The system 100 may include a host device 110, a pair of portable wireless listening devices 130, and a charging case 150. The host device 110 Figure 1 1 is depicted as a smartphone, but may be any electronic device that can transmit audio data to the portable listening device 130. Other non-limiting examples of suitable host devices 110 include laptop computers, desktop computers, tablet computers, smart watches, audio systems, video players, televisions, etc.

[0031] like Figure 1, the host device 110 may be wirelessly coupled to the portable wireless listening device 130 and the charging case 150 via wireless communication links 160 and 162. Similarly, the portable wireless listening device 130 may be communicatively coupled to the charging case 150 via a wireless communication link 164. Each of the wireless communication links 160, 162, and 164 may be a known and established wireless communication protocol, such as a Bluetooth protocol, a WiFi protocol, or any other acceptable protocol that enables electronic devices to wirelessly communicate with each other. Thus, the host device 110 may directly exchange data with the portable wireless listening device 130, such as audio data that may be transmitted to the wireless listening device 130 via the wireless link 160 for playback to the user, and audio data that may be received by the host device 110 (e.g., recorded / input from a microphone in the portable wireless listening device 130). In some specific implementations, the host device 110 can also be wirelessly coupled to the charging case 150 via the wireless link 162, so that the host device 110 can exchange data with the charging case, such as data indicating the battery charge level data of the case 150, data indicating the battery charge level of the portable wireless listening device 130, and data indicating the pairing status of the portable wireless listening device 130.

[0032] The portable wireless listening device 130 can be stored within a housing 150, which can protect the device 130 from loss and / or damage when the device is not in use, and can also provide power to recharge the battery of the portable wireless listening device 130, as discussed below. In some embodiments, the portable wireless listening device 130 can also be wirelessly coupled to the charging housing 150 via a wireless link 164, so that when the device is worn by a user, audio data from the housing 150 can be transmitted to the portable wireless listening device 130. As an example, the charging housing 150 can be coupled to an audio source different from the host device 110 via a physical connection (e.g., an auxiliary cable connection). The audio data from the audio source can be received by the charging housing 150, which can then wirelessly transmit the data to the wireless listening device 130. In this way, the user can hear audio stored on or generated by the audio source through the wireless listening device 130 even if the audio source does not have wireless audio output capabilities.

[0033] As will be understood herein, the portable wireless listening device 130 may include several features that enable the device to be comfortably worn by the user for extended periods of time, or even for all day. The shape and size of each portable listening device 130 may be set to fit firmly between the tragus and antitragus of the user's ear, so that the portable listening device will not fall out of the ear even when the user is exercising or otherwise actively moving. Its functionality may also enable the wireless listening device 130 to provide an audio interface to the host device 110, so that the user may not need to utilize the graphical interface of the host device 110. In other words, the wireless listening device 130 may be so complex that it may enable the user to perform daily operations from the host device 110 only by interacting with the wireless listening device 130. This may create further independence from the host device 110 by not requiring the user to physically interact with the host device 110 and / or view the display screen of the host device, particularly when the functionality of the wireless listening device 130 is combined with the voice control capabilities of the host device 110. Therefore, the wireless listening device 130 may provide a true hands-free experience for the user.

[0034] Details of example earpieces that may represent each of the portable wireless listening devices 130 are discussed below. However, reference is first made to Figure 2 , which is a simplified block diagram of various components of a wireless listening system 200 according to some embodiments, the wireless listening system includes a host device 210, a pair of portable wireless listening devices (PWLDs) 230 (e.g., a right PWLD 230 and a left PWLD 230), and a charging case 250. The system 200 may represent Figure 1 , and the host device 210, the portable wireless listening device 230, and the charging case 250 may represent the host device 110, the portable wireless listening device 130, and the charging case 150, respectively. Each portable wireless listening device 230 can receive and generate sound to provide an enhanced user interface for the host device 210. For convenience, the following discussion refers to a single portable wireless listening device 230, but it should be understood that in some embodiments, a pair of portable listening devices can work together to be used for the left and right ears of the user, respectively, and each portable wireless listening device in the pair can include the same or similar components.

[0035] The portable wireless listening device 230 may include a computing system 231 that executes computer-readable instructions stored in a memory bank (not shown) for performing a plurality of functions of the portable wireless listening device 230. The computing system 231 may be one or more suitable computing devices, such as a microprocessor, a computer processing unit (CPU), a digital signal processing unit (DSP), a field programmable gate array (FPGA), an application specific integrated circuit (ASIC), etc.

[0036] The computing system 231 may be operably coupled to the user interface system 232, the communication system 234, and the sensor system 236 to enable the portable wireless listening device 230 to perform one or more functions. For example, the user interface system 232 may include a driver (e.g., a speaker) for outputting sound to the user, one or more microphones for inputting sound from the environment and the user, one or more LEDs for providing visual notifications to the user, a pressure sensor or a touch sensor (e.g., a resistive or capacitive touch sensor) for receiving user input, and / or any other suitable input or output device. The communication system 234 may include wireless and wired communication components to enable the portable wireless listening device 230 to send data / commands and receive data / commands from the host device 210. For example, in some embodiments, the communication system 234 may include circuitry that enables the portable wireless listening device 230 to communicate with the host device 210 via a wireless link 260 via Bluetooth or other wireless communication protocols. In some embodiments, the communication system 234 may also enable the portable wireless listening device 230 to communicate wirelessly with the charging shell 250 via a wireless link 264. Sensor system 236 may include proximity sensors (eg, optical sensors, capacitive sensors, radar, etc.), accelerometers, microphones, and any other type of sensor that may measure parameters of an external entity and / or environment.

[0037] The portable wireless listening device 230 may also include a battery 238, which may be any suitable energy storage device capable of storing energy and releasing the stored energy to operate the portable wireless listening device 230, such as a lithium-ion battery. The discharged energy may be used to power the electrical components of the portable wireless listening device 230. In some embodiments, the battery 238 may be a rechargeable battery, which enables the battery to be repeatedly charged as needed to replenish its stored energy. For example, the battery 238 may be coupled to a battery charging circuit (not shown), which is operably coupled to receive power from the charging housing interface 239. The housing interface 239 may then be electrically coupled to the earpiece interface 252 of the charging housing 250. In some embodiments, power may be received from the charging housing 250 by the portable wireless listening device 230 via electrical contacts within the housing interface 239. In some embodiments, the portable wireless listening device 230 may receive power wirelessly via a wireless power receiving coil within the housing interface 239.

[0038] The charging case 250 may include a battery 258 that may store and release energy to power circuitry within the charging case 250 and to recharge the battery 238 of the portable wireless power listening device 230. As described above, in some embodiments, the circuitry within the earpiece interface 252 may transfer power to the portable wireless listening device 230 via a wired electrical connection between contacts in the charging case 250 that are electrically coupled to contacts in the portable wireless listening device 250 to charge the battery 238. While in some embodiments, the case 250 may be a device that provides power to charge the battery 238 via a wired interface with the device 230, in other embodiments, the case 250 may provide power to charge the battery 238 via a wireless power transfer mechanism instead of or in addition to a wired connection. For example, the earpiece interface may include a wireless power transmitter coil that may be coupled to a wireless power receiving coil within the portable wireless listening device 230.

[0039] The charging case 250 may also include a case computing system 255 and a case communication system 251. The case computing system 255 may be one or more processors, ASICs, FPGAs, microprocessors, etc., for operating the case 250. The case computing system 255 may be coupled to the earpiece interface 252 and may control the charging function of the case 250 to recharge the battery 238 of the portable wireless listening device 230, and the case computing system 255 may also be coupled to the case communication system 251 for operating the interactive functions of the case 250 with other devices (including the portable wireless listening device 230). In some embodiments, the case communication system 251 includes a Bluetooth component or any other suitable wireless communication component that wirelessly sends and receives data with the communication system 234 of the portable wireless listening device 230. To this end, each of the charging case 250 and the portable wireless listening device 230 may include an antenna formed by a conductive body to send and receive such signals. The case 250 may also include a user interface 256 that is operably coupled to the case computing system 255 to alert the user of various notifications. For example, the user interface may include a speaker that can emit an audible noise that can be heard by the user, and / or one or more LEDs or similar lights that can emit light that can be seen by the user (e.g., to indicate whether the portable listening device 230 is being charged by the case 250 or to indicate whether the case battery 258 is low on energy or is being charged).

[0040] The host device 210 (to which the portable wireless listening device 230 is an accessory) may be a portable electronic device such as a smart phone, a tablet computer, or a laptop computer. The host device 210 may include a host computing system 212 coupled to a battery 214 and a host memory bank 134, the host memory bank containing lines of code that can be executed by the host computing system 212 for operating the host device 210. The host device 210 may also include a host sensor system 215 (e.g., an accelerometer, a gyroscope, a light sensor, etc.) for allowing the host device 210 to sense the environment, and a host user interface system 216 (e.g., a display, a speaker, a button, a touch screen, etc.) for outputting information to a user and receiving input from a user. Additionally, the host device 210 may also include a host communication system 218 for allowing the host device 210 to send and / or receive data from the Internet or a cellular tower via wireless communications (e.g., wireless fidelity (WiFi), long term evolution (LTE), code division multiple access (CDMA), global system for mobiles (GSM), Bluetooth, etc.). In some embodiments, the host communication system 218 can also communicate with the communication system 234 in the portable wireless listening device 230 via the wireless communication link 262, so that the host device 210 can send audio data to the portable wireless listening device 230 to output sound, and receive data from the portable wireless listening device 230 to receive user input. The communication link 262 can be any suitable wireless communication line, such as a Bluetooth connection. By enabling communication between the host device 210 and the portable wireless listening device 230, the wireless listening device 230 can enhance the user interface of the host device 210.

[0041] earpiece

[0042] Reference now FIG. 3A to FIG. 3C , these figures are simplified views of a wireless handset 300 according to some embodiments. Specifically, Figure 3A illustrates a front perspective view of a wireless handset according to an embodiment of the present disclosure; Figure 3B Illustrated Figure 3A a rear perspective view of the wireless handset shown in ; and Figure 3C Illustrated Figure 3A A front perspective view of a wireless earpiece with its ear tips removed is shown in FIG. A person skilled in the art will readily appreciate that FIG. 3A to FIG. 3C The description of earpiece 300 in is provided for illustrative purposes only, and as described above, although earpiece 300 is an in-ear headphone that represents a specific example of a portable listening device according to some embodiments, embodiments of the present invention are not limited to in-ear headphones or the specific features of earpiece 300 as discussed below.

[0043] The earpiece 300 may include a housing 310 and an ear tip 320 that directs sound from an internal audio driver (e.g., a speaker) out of the housing 310 and into the ear canal of the user. The housing 310 may be made of, for example, a hard radio frequency (RF) transparent plastic such as acrylonitrile butadiene styrene (ABS) or polycarbonate. In some embodiments, the housing 310 may be made of one or more parts that may be joined together (e.g., using tongue-and-groove joints and appropriate adhesives) to form a one-piece housing structure having a substantially seamless appearance.

[0044] The stem 314 can be substantially cylindrical in construction, but it can include a planar area 330 that does not follow the curvature of the cylindrical construction. The planar area 330 can indicate an area in which the wireless listening device can receive user input. For example, user input can be entered by squeezing the stem 314 at the planar area 330 or sliding a finger along a portion of the planar area. The stem 314 can also include electrical contacts 340 and 342 for contacting corresponding electrical contacts in a charging case that can store and charge a pair of earpieces 300. The electrical contacts 340, 342 provide a physical interface that can be electrically coupled to corresponding electrical contacts in a corresponding charging case (e.g., charging case 150). It should be understood that the embodiments are not limited to FIG. 3A to FIG. 3C For example, in some embodiments, the housing does not include a rod or similar structure, and in some embodiments, an anchor or other structure can be attached to the housing or extend away from the housing to further secure the earpiece to the user's ear.

[0045] Figure 3A Also shown in the figure is a cap 346, which is part of the entire housing 310 and can be attached to the end of the rod 314, thereby forming a watertight seal with the rod. A bottom microphone (not shown) can be attached to the inner surface of the cap 346, and the cap can include an acoustic aperture (not shown) that allows the microphone to capture sound from the environment. The cap 346 may also include two seats on opposite sides of the cap along its outer surface for two contacts 340, 342. The two seats are recessed by a sufficient amount so that the contacts 340, 342 can be fixed to the seats and positioned flush with the outer surface of the cap 346, thereby producing a smooth seamless structure with improved appearance and reliability. Each of the contacts 340, 342 can be electrically connected to the circuit in the rod 314 through an appropriate cutout or opening in the cap 346 that can be covered by the contacts.

[0046] In some embodiments, the housing 310 may be formed of a seemingly unitary outer structure without any obvious seams or rough edges. The housing 310 may form a leather shell that defines an internal cavity (not shown), and various components of the earpiece 300 are positioned in the internal cavity. For example, encapsulated in the housing 310 may be a processor or other type of controller, one or more computer-readable memories, wireless communication circuits, antennas, rechargeable batteries, and power receiving circuits. The housing 310 may also accommodate an audio driver (i.e., a speaker) and one or more microphones. The speaker and one or more microphones may each be positioned within the housing 310 adjacent to an audio opening extending through the housing 310 to allow the speaker and one or more microphones to transmit and receive audio waves through the housing. Various sensors (such as accelerometers, photodetectors, force and touch sensors, including capacitive pixels according to the embodiments disclosed herein) may also be disposed within the housing 310. Since all of the various components described above are disposed within the housing 310, FIG. 3A to FIG. 3C None of the components are shown in any of the .

[0047] Some or all of these audio openings may be covered by a mesh. Figure 3C As shown, the grid 350 may be disposed above the audio orifice formed in the speaker housing 312. The speaker may be positioned within the speaker housing and aligned to emit sound into the user's ear canal through the audio orifice, through the grid 350, and through the central channel 322 extending through the ear plug 320. As another example, a rear vent (not shown) may be formed through the speaker housing 312 and covered with the grid 352. The rear vent may be acoustically coupled to the rear volume of the speaker housing to provide improved acoustic performance of the earpiece. As another example, a microphone orifice (also not shown) may be formed through the housing 310 near the position where the speaker housing 312 engages with the rod 314 and is covered by the grid 354. The microphone may be disposed within the housing 310 at a position adjacent to the microphone orifice so that the microphone may receive sound waves through the grid 354 and through the microphone orifice.

[0048] The ear tip 320 may be made primarily of a deformable material, and its size and shape may be set to fit into the ear canal of the user. In this way, the ear tip 320 and the speaker housing 312 may be combined to form the main support mechanism for fixing the earpiece 300 in the ear of the user. FIG. 3A to FIG. 3C In the embodiment depicted in FIG. 1 , the ear tips may be removably attached to the speaker housing 312 and Figure 3A is shown in the attached state and is Figure 3CEarpieces according to other embodiments need not include a deformable eartip, but may rely on an earpiece housing (e.g., speaker housing 312) that is the primary support mechanism for the earpiece 300 when the earpiece is positioned in the user's ear.

[0049] In-ear detection

[0050] The earpiece 300 may include a plurality of capacitive pixels that may be used to determine when the earpiece is worn in the user's ear. Each capacitive pixel may be a touch sensor that measures the capacitance at the sensor. When positioned near a person's skin, the capacitance at the pixel sensor increases, thus enabling the plurality of pixel sensors to be monitored by a circuit to determine whether the earpiece is in the user's ear.

[0051] refer to Figure 4 , which is about FIG. 3A to FIG. 3C A simplified, enlarged front perspective view of the earpiece 300 is depicted, and in some embodiments, the earpiece 300 may include three capacitive pixels 402, 404, 406 that are strategically positioned along the housing 310 (directly below the outer surface) at a location where, when the earpiece 300 is worn by the user, the pixels may be in physical contact with or in close proximity to the surface of the user's ear (i.e., skin).

[0052] like Figure 4 As shown, the depicted embodiment includes three separate capacitive pixels (often referred to herein as "pixels"). When observed from a viewpoint looking directly at the acoustic aperture 350 (along axis 410), two pixels in the pixel are radially spaced at least 90 degrees from each other. Spacing two pixels at least 90 degrees (and in some embodiments at least 120 degrees) helps to ensure that the pixels detect skin contact independently of each other, thereby reducing false positive readings, in which the pixel indicates that the earpiece is in the user's ear when the earpiece is alternatively contacted with a finger, palm, or other parts that may cause the capacitance measurement result of one pixel in the pixel to increase to above the detection threshold without causing a similar increase in capacitance at another pixel. Including the third pixel further reduces false positives. The embodiment is not limited to any specific number of capacitive pixels or any specific position of the pixel. Those skilled in the art will appreciate that the position of the pixel can depend on the size and shape of the earpiece housing and the number of pixels incorporated into the housing and the size and shape of each pixel. In some embodiments, the position can be determined based on a heat map developed according to a fitting test from tens or hundreds or more users, which indicates the position of physical contact with the ear of each user along the housing.

[0053] Each capacitive pixel can be disposed within the cavity formed by housing 310 in close proximity to the outer surface of the housing. The capacitive pixels can be very thin (e.g., 500 microns or less in some embodiments; or 100 microns or less in some embodiments) and fit within a dedicated recessed slot or cutout formed in the inner surface of housing 310, such that the pixel is spaced from the outer surface by only the thickness of the housing in the region where each slot is formed.

[0054] For illustration, refer to Figure 5A and Figure 5B , each of which is a simplified cross-sectional view of a portion of an earplug housing 310 according to some embodiments taken from two different angles. Figure 5A and Figure 5B As shown, thin cuts or slots 502, 504, 506 can be formed in the housing wall to accommodate capacitive pixels 402, 404, 406, respectively. Each slot 502, 504, 506 can have a depth that allows its corresponding thin capacitive pixel to be completely recessed in the slot without any part of the capacitive pixel protruding in a protruding manner. A flexible circuit (not shown) can extend along the inner surface 510 of the housing 310 and electrically couple the capacitive pixel to a circuit that routes signals between the pixel and the sensor control circuit, such as an ASIC or similar controller or appropriate circuit. The sensor control circuit can drive and monitor each of the capacitive pixels 402, 404, 406 by, for example, sending a control signal to each pixel to read the capacitance at the pixel at one or more predetermined frequencies (e.g., a frequency between 0.5 Hz and 1000 Hz). In some embodiments, the sensor control circuit sends a separate control signal spaced apart in time to each capacitive pixel at the same frequency so that the three pixels 402, 404, 406 are read out sequentially and repeatedly.

[0055] The sensor control circuit can be part of a controller or other processor (such as the earpiece computing system 231) within the earpiece 300 or can communicate with the controller or other processor to implement different operating modes for the earbud 300 that enable the earbud to save battery power. For example, when the capacitive pixels indicate that the earpiece 300 is not positioned in the user's ear, the controller can place the earbud 300 in a low power or sleep mode to save battery power. The sensor circuit can execute a predetermined algorithm, an artificial intelligence engine, or other technology to determine when the measurement results obtained from the capacitive pixels indicate whether the earpiece is in the user's ear, as further discussed below. For convenience and reference, the various techniques and methods relied upon by the sensor circuit for making in-ear or out-of-ear determinations are collectively referred to herein as "in-ear detection" algorithms.

[0056] Sample Pixels

[0057] Fig. 6Aand Figure 6B An example of a pixel 600 according to some embodiments is shown in Fig. 6A is a simplified top plan view of pixel 600, and Figure 6B 6 is a simplified cross-sectional view of a pixel 600. As shown, the pixel 600 may include a sensing region 610 (i.e., an electrode) surrounded by a guard ring 620, which is separated from the sensing region 610 by a gap 630. In some implementations, the gap 630 may be air or may be filled with a dielectric material. Each of the sensing region 610 and the guard ring 620 may be a thin conductive material, such as copper, indium tin oxide (ITO), or a similar conductive metal.

[0058] Reference now Figure 6B , which depicts pixel 600 formed within a slot in housing 310, which is labeled slot 502, but slots 504 and 506 are also shown. Figure 6B As shown, the dielectric layer 640 is disposed between the sensing region 610 and the ground layer 650, so that the sensing region 610, the dielectric layer 640 and the ground layer 650 form a vertical layer stack. The sensing region 610, the guard ring 620 and the ground layer 650 can all be conductive layers made of suitable metals or similar materials. The ground layer 650 can be coupled to the ground and can completely cover the back side of the pixel 600 to protect the sensing region 610 from noise. In some embodiments, the dielectric layer 640 can be a stack of two or more layers, such as a polyimide layer and a protective layer or a covering dielectric layer disposed between the polyimide layer and the ground shield. Although not shown, the various layers can be bonded to each other by one or more adhesive layers.

[0059] In the depicted embodiment, the sensing region 610 has a circular shape with a diameter of X, and the gap 630 is a ring concentric with the sensing region 610. In some embodiments, X is less than 4 mm, between 1 mm and 3 mm, or approximately 2 mm. However, as will be appreciated by those skilled in the art, the embodiments are not limited to any particular size or shape of the sensing region, the guard ring, or the gap separating the two. Additionally, it will be appreciated that the embodiments disclosed herein are not limited to Fig. 6A and Figure 6B Specific capacitive pixel 600 is shown in FIG. 6. Alternatively, a variety of different types and configurations of capacitive pixels may be employed in place of or in addition to pixel 600.

[0060] In operation, in some embodiments, guard ring 620 and ground layer 650 can be coupled to ground, and sensing region 610 coupled to a drive circuit (not shown) can be periodically pulsed to measure the parasitic capacitance at sensing region 610 (electrode) in the system. Figure 4Measurements of pixels 402, 404, and 406 in the embodiment depicted in the figure can then be collected in this manner and sent to a sensor control circuit, which can determine, based on an in-ear detection algorithm, whether the collected measurements indicate that the earpiece may be positioned within the user's ear.

[0061] Those skilled in the art will appreciate that a variety of different in-ear detection algorithms may be employed in making such determinations. As one example, the algorithm may determine whether the earpiece is in the user's ear based on whether the values ​​of multiple measurements of two or more of the pixels are greater than or less than a predetermined threshold. In other embodiments, when the measured capacitance C is above a predetermined level (e.g., Figure 7 The algorithm may infer that a single pixel is in contact with the user's skin (and therefore likely positioned within the user's ear) when the measured capacitance is below a predetermined level (e.g., above the on value 710 indicated in the graph of FIG. 1 ), and that the single pixel is in contact with the user's skin (and therefore likely positioned within the user's ear) when the measured capacitance is below a predetermined level (e.g., at Figure 7 ), the algorithm can infer that the individual pixel is not in contact with or directly adjacent to the user's skin 675 (and therefore is unlikely to be in the user's ear), and if the measured capacitance is between the on and off values, the algorithm can mark the pixel as uncertain as to whether it is in contact with human skin (and therefore uncertain as to whether the pixel is in the user's ear). The algorithm can then make a determination as to whether the earpiece is likely to be positioned in the user's ear based on the measurements for each of the pixels.

[0062] As an illustrative but non-limiting example, if the capacitance measurements of pixels 402 and 404 are above the turn-on point 710, the algorithm may infer that the earpiece is in the ear, as long as the measured capacitance of pixel 406 is below the turn-off point 720. As another illustrative but non-limiting example, if the capacitance measurement of pixel 402 is above the turn-on point 710 but the measurement of at least one of pixels 404 and 406 is below the turn-off point, the algorithm may infer that the earpiece is not in the ear, regardless of the measured capacitance of the other pixel 404 or 406. As yet another illustrative but non-limiting example, if the capacitance measurement of pixel 402 is above the turn-on point 710 and the capacitance measurements of both pixels 404 and 406 are between the turn-on point and the turn-off points 710, 720, the algorithm may infer that the earpiece is in the user's ear. Those skilled in the art will be able to program the control circuit with an appropriate algorithm based on the measurements taken during the testing process. In other embodiments, the algorithm may be an artificial intelligence engine that is trained to recognize capacitance measurements from pixels that indicate whether the earpiece is in the user's ear. Additionally, one skilled in the art will appreciate that Figure 7The specific on and off thresholds stated in are for illustrative purposes only. Figure 7 The capacitance levels for the specific on and off levels shown in can be used in other embodiments and can be determined using various known testing procedures and techniques.

[0063] Thermal drift mitigation

[0064] When the measurements are made, the capacitance measurements may change over time due to changes in temperature. For example, when the earpiece 300 is placed in the ear of a user, the temperature of the earpiece may sometimes increase due to body heat being transferred from the user to the earpiece. Changes in temperature may affect the capacitance measured by the capacitive pixels, which in turn may adversely affect the conclusions drawn by the in-ear detection algorithm from the capacitance measurements.

[0065] To mitigate the potential effects of such temperature variations (ie, thermal drift), some embodiments include AC shielding around the sensing area of ​​each pixel, such as the following in conjunction with Fig. 8A and Figure 8B As described, Fig. 8A and Figure 8B 800a and 800b according to some embodiments. Pixel sensors 800a, 800b can be similar to pixel 600 discussed above and include a sensing region 810, a guard ring 820 separated from the sensing region by a gap 830. Pixel 800 can also include a conductive plane 850 separated from the sensing region and the guard ring by a dielectric layer 840. Each of these major elements (sensing region 810, guard ring 820, gap 830, dielectric layer 840, and stratum 850) can be physically similar to the above description of the sensing region 810, guard ring 820, gap 830, dielectric layer 840, and stratum 850. Fig. 6A and Figure 6B Elements discussed with the same names (or similar reference numerals) are referred to. Additionally, in capacitive pixel 800a, guard ring 820 and conductive plane 850 may be directly coupled to ground.

[0066] Pixel 800b is different. Unlike the guard ring 620 and ground plane 650 in pixel 600, the guard ring 820 and the conductive plane 850 are not directly grounded. Instead, these conductive structures can be electrically coupled to receive a signal 870 that simulates a sensing pulse 860 applied to the sensing region 850. In this way, whenever pulse 860 initiates a measurement of the capacitance at the sensing region 850 (i.e., sampling the capacitance at the sensing region 850), pulse 870 is applied to the guard ring 820 and the AC plane 850, so that the baseline signal of each element moves together, thereby modulating any thermal drift in the signal. At the same time, the conductive plane 850 acts as an AC shield, which shields the sensing region 850 from external noise.

[0067] Reduction of humidity

[0068] Now refer to Fig. 9A , which is a simplified cross-section and schematic diagram of a pixel 900 according to some embodiments. Pixel 900 can be similar in construction to pixels 600 and 800, and therefore will not be discussed in further detail except to note the operational differences between pixel 900 and the previously described pixels. Thus, pixel sensor 900 can include a sensing region 910, a guard ring 920 separated from the sensing region by a gap 930. Pixel 900 can also include a conductive plane 950, which is separated from the sensing region and the guard ring by a dielectric layer 940. Each of these major elements (sensing region 910, guard ring 920, gap 930, dielectric layer 940, and conductive plane 950) can be physically similar to the above description of Fig. 6A , Figure 6B and Fig. 8A , Figure 8B Elements discussed have the same names (or similar reference numerals).

[0069] When the earpiece is exposed to moisture (such as water droplets), the capacitance reading from the pixel can show the capacitance between the water and the sensing area of ​​the pixel (in Fig. 9A Indicated as capacitor C1 in the figure) and the capacitance between the water droplet and the guard ring (in Fig. 9A 9), and leakage current 980 may be generated by water droplets between the sensing area 910 and the grounded guard ring 920. Thus, water droplets or other moisture on the earpiece may simulate skin contact and may potentially lead to inaccurate in-ear detection readings.

[0070] To distinguish water droplets or other moisture that may be in contact with the pixel, some embodiments electrically couple the guard ring 920 and the conductive shield 950 to receive a signal 970 that simulates the sensing pulse 960 applied to the sensing region 950. These embodiments may then employ a multi-step sampling process in which the capacitance at the sensing region 910 is sampled at a point in time when the guard ring 920 and the conductive shield 950 are grounded (e.g., as shown in FIG. 1 ). Fig. 9A ), and then sampling at a second point in time (e.g., milliseconds later) when the guard ring 920 and the conductive shield 950 are pulsed with the signal 970 (e.g., as shown in FIG. Fig. 9B ), which simulates a sensing pulse 960 applied to the sensing region 950. In this way, each time pulse 960 initiates a measurement of the capacitance at the sensing region 950 (i.e., samples the capacitance at the sensing region 950), pulse 970 is applied to the guard ring 920 and the conductive plane 950, thereby eliminating or greatly reducing Fig. 9AThe potential leakage current is shown in 980. The difference between the two signals can then be used to identify the leakage current and determine that moisture is affecting the sensor reading rather than skin contact.

[0071] Additional Implementation

[0072] For the purpose of illustration, the foregoing description uses specific naming to provide a thorough understanding of the embodiments. However, it will be apparent to those skilled in the art that specific details are not required in order to practice the embodiments. Therefore, for the purpose of illustration and description, the foregoing description of the specific embodiments described herein is presented. They are not intended to be exhaustive or to limit the embodiments to the disclosed precise forms. In addition, although different embodiments of the present invention are disclosed above, the specific details of a particular embodiment may be combined in any suitable manner without departing from the essence and scope of the embodiments of the present invention. In addition, it will be apparent to those skilled in the art that, in view of the above teachings, many modifications and variations are feasible.

[0073] Finally, it is understood that the use of personally identifiable information should be subject to privacy policies and practices that are generally recognized to meet or exceed industry or government requirements for maintaining user privacy. Specifically, personally identifiable information data should be managed and processed to minimize the risk of unintentional or unauthorized access or use, and the nature of the authorized use should be clearly stated to the user.

Claims

1. A handset, comprising: a device housing, the device housing defining an interior cavity within the device housing; an acoustic aperture formed through the device housing and having an opening at an outer surface of the device housing; an audio driver disposed within the device housing and aligned to emit sound through the acoustic aperture; a plurality of capacitive pixels disposed within the interior cavity, wherein at least two of the capacitive pixels are radially disposed about the acoustic aperture and spaced at least 90 degrees apart from one another; and A sensor control circuit is disposed within the internal cavity and is operably coupled to drive the plurality of capacitive pixels at a predetermined frequency to read out the capacitance at each of the plurality of capacitive pixels and determine whether the earpiece is within an ear of a user.

2. The handset of claim 1, wherein: the device housing comprising a housing wall defining both an exterior surface of the earpiece and an interior surface of the device housing; The handset further includes a plurality of recessed areas formed in the housing wall; and Each of the plurality of capacitive pixels is disposed in only one of the plurality of recessed regions.

3. The earpiece of claim 2, wherein each capacitive pixel has a thickness of 500 microns or less.

4. The handset of claim 1 , wherein each capacitive sensor comprises a layer stack, the layer stack comprising: a first conductive layer, the first conductive layer comprising an active region and a guard ring, the guard ring surrounding the active region and spaced apart from the active region; Conductive shielding layer; and A dielectric layer is disposed between the first conductive layer and the conductive shielding layer.

5. The handset of claim 4, wherein the sensor control circuit is further configured to apply a pulse voltage to the guard ring and the conductive shielding layer at the same frequency and time as driving the capacitive pixels.

6. The earpiece of claim 4 , wherein the sensor control circuit is configured to drive the plurality of pixels according to a multi-step process in which the capacitance of each capacitive pixel is measured at one point in time when the guard ring and the conductive shield layer are grounded, and then measured at a second point in time when the guard ring and the conductive shield layer are pulsed with a signal that simulates a sensing pulse applied to a sensing area.

7. The earpiece of claim 1, wherein at least two of the plurality of capacitive pixels are radially disposed around the acoustic aperture and are spaced at least 120 degrees apart from one another. 8 . The earpiece of claim 1 , wherein a diameter of the sensing area of ​​each of the plurality of capacitive pixels is 4 mm or less.

9. The earpiece of claim 1 , wherein the sensor control circuit determines whether the earpiece is in the ear of the user based on a predetermined in-ear detection algorithm, the predetermined in-ear detection algorithm comprising determining whether a plurality of measured capacitance values ​​of two or more pixels are greater than or less than a predetermined threshold.

10. The earpiece of claim 1, wherein the sensor control circuit determines whether the earpiece is in an ear of a user based on an artificial intelligence engine.

11. A handset, comprising: a device housing comprising a housing wall defining both an exterior surface of the earpiece and an interior surface of the device housing; an acoustic aperture formed through the device housing and having an opening at an outer surface of the device housing; an audio driver disposed within the device housing and aligned to emit sound through the acoustic aperture; a plurality of recessed areas formed in the housing wall; a plurality of capacitive pixels disposed within the device housing, wherein each capacitive pixel of the plurality of capacitive pixels is disposed within a unique one of the plurality of recessed regions, and wherein at least two of the capacitive pixels are radially disposed about the acoustic aperture and spaced at least 120 degrees apart from one another; and A sensor control circuit is disposed within the internal cavity and is operably coupled to drive the plurality of capacitive pixels at a predetermined frequency to read out the capacitance at each of the plurality of capacitive pixels and determine whether the earpiece is within the user's ear based on an algorithm.

12. The handset of claim 11, wherein each capacitive sensor comprises a layer stack, the layer stack comprising: a first conductive layer, the first conductive layer comprising an active region and a guard ring, the guard ring surrounding the active region and spaced apart from the active region; Conductive shielding layer; and a dielectric layer disposed between the first conductive layer and the conductive shielding layer.

13. The handset of claim 12, wherein the sensor control circuit is further configured to apply a pulse voltage to the guard ring and the conductive shielding layer at the same frequency and time as driving the capacitive pixels.

14. The earpiece of claim 12 , wherein the sensor control circuit is configured to drive the plurality of pixels according to a multi-step process in which the capacitance of each capacitive pixel is measured at one point in time when the guard ring and the conductive shield layer are grounded, and then measured at a second point in time when the guard ring and the conductive shield layer are pulsed with a signal that simulates the sensing pulse applied to the sensing area.

15. A portable acoustic device, comprising: a device housing comprising a speaker housing portion and a stem portion extending away from the speaker housing portion, wherein the speaker housing portion and the stem portion combine to define an interior cavity within the device housing; an acoustic aperture formed through a wall of the speaker housing portion and having an opening at an outer surface of the device housing; an audio driver disposed within the speaker housing portion and aligned to emit sound through the acoustic aperture; a plurality of capacitive pixels disposed within the interior cavity, wherein at least two of the capacitive pixels are radially disposed about the acoustic aperture and spaced at least 90 degrees apart from one another; and A sensor control circuit is disposed within the internal cavity and is operably coupled to drive the plurality of capacitive pixels at a predetermined frequency to read out the capacitance at each of the plurality of capacitive pixels and determine whether the earpiece is within the user's ear based on an algorithm.

16. The portable acoustic device of claim 15, wherein each capacitive sensor comprises a layer stack, the layer stack comprising: a first conductive layer, the first conductive layer comprising an active region and a guard ring, the guard ring surrounding the active region and spaced apart from the active region; Conductive shielding layer; and A dielectric layer is disposed between the first conductive layer and the conductive shielding layer. 17 . The portable acoustic device of claim 16 , wherein the sensor control circuit is further configured to apply a pulse voltage to the guard ring and the conductive shielding layer at the same frequency and time as driving the capacitive pixel.

18. A portable acoustic device according to claim 16, wherein the sensor control circuit is configured to drive the plurality of pixels according to a multi-step process, in which the capacitance of each capacitive pixel is measured at one point in time when the guard ring and the conductive shielding layer are grounded, and then measured at a second point in time when the guard ring and the conductive shielding layer are pulsed with a signal that simulates the sensing pulse applied to the sensing area.

19. The portable acoustic device of claim 15, wherein: the device housing comprising a housing wall defining both an exterior surface of the earpiece and an interior surface of the device housing; The handset further includes a plurality of recessed areas formed in the housing wall; and Each of the plurality of capacitive pixels is disposed in only one of the plurality of recessed regions.

20. The portable acoustic device of claim 19, wherein each capacitive pixel has a thickness of 100 micrometers or less, and a diameter of the sensing area of ​​each capacitive pixel of the plurality of capacitive pixels is 4 mm or less.

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