Patent Description:
Wearable audio devices, such as headphones, produce sound for a wearer using an electro-acoustic transducer. These wearable audio devices may take various form factors. In some cases, design, computational and power constraints can limit the interface options for these wearable audio devices. Accordingly, it can be difficult to implement a complete set of interface commands without compromising one or more constraints.

<CIT>, <CIT>, <CIT> and <CIT> disclose prior art devices using a capacitive touch interface.

The present invention relates to a wearable audio device according to claim <NUM>. Advantageous embodiments are recited in dependent claims.

It is noted that the drawings of the various implementations are not necessarily to scale. The drawings are intended to depict only typical aspects of the disclosure, and therefore should not be considered as limiting the scope of the invention.

As noted herein, various aspects of the disclosure generally relate to wearable audio devices with a capacitive touch interface. More particularly, aspects of the disclosure relate to wearable audio devices having a capacitive touch interface with electrode borders that enhance slide angle detection when compared with conventional capacitive touch interfaces.

Commonly labeled components in the FIGURES are considered to be substantially equivalent components for the purposes of illustration, and redundant discussion of those components is omitted for clarity.

Aspects and implementations disclosed herein may be applicable to a wide variety of speaker systems, such as wearable audio devices in various form factors, such as headphones (whether on or off ear), headsets, watches, eyeglasses, neck-worn speakers, shoulder-worn speakers, body-worn speakers, etc. Unless specified otherwise, the term wearable audio device, as used in this document, includes headphones and various other types of personal audio devices such as head, shoulder or body-worn acoustic devices that include one or more acoustic drivers to produce sound. Some particular aspects disclosed may be particularly applicable to personal (wearable) audio devices such as in-ear headphones (also referred to as earbuds), eyeglasses or other head-mounted audio devices. It should be noted that although specific implementations of speaker systems primarily serving the purpose of acoustically outputting audio are presented with some degree of detail, such presentations of specific implementations are intended to facilitate understanding through provision of examples and should not be taken as limiting either the scope of disclosure or the scope of claim coverage.

Aspects and implementations disclosed herein may be applicable to speaker systems that either do or do not support two-way communications, and either do or do not support active noise reduction (ANR). For speaker systems that do support either two-way communications or ANR, it is intended that what is disclosed and claimed herein is applicable to a speaker system incorporating one or more microphones disposed on a portion of the speaker system that remains outside an ear when in use (e.g., feedforward microphones), on a portion that is inserted into a portion of an ear when in use (e.g., feedback microphones), or disposed on both of such portions. Still other implementations of speaker systems to which what is disclosed and what is claimed herein is applicable will be apparent to those skilled in the art.

While described by way of example, wearable audio devices such as in-ear headphones (e.g., earbuds), audio accessories or clothing (e.g., audio hats, audio visors, audio jewelry, neck-worn speakers or audio eyeglasses (also referred to as eyeglass headphones) herein, the wearable audio devices disclosed herein can include additional features and capabilities. That is, the wearable audio devices described according to various implementations can include features found in one or more other wearable electronic devices, such as smart glasses, smart watches, etc. These wearable audio devices can include additional hardware components, such as one or more cameras, location tracking devices, microphones, etc., and may be capable of voice recognition, visual recognition, and other smart device functions. The description of wearable audio devices included herein is not intended to exclude these additional capabilities in such a device.

Various particular implementations include wearable audio devices, such as earbuds, and user interfaces for improving gesture detection on those user interfaces when compared with conventional devices. In certain implementations, the wearable audio device includes a capacitive touch interface with a contact surface and a set of (at least two) electrodes underlying the contact surface for detecting a touch command. Neighboring electrodes in the set of electrodes share a border with either an arcuate profile across the contact surface, or a piecewise profile approximating a non-linear path across the contact surface. The electrodes are aligned directly adjacent one another and have complementary faces matching the border, such that the contact surface detects motion as a user moves across the surface from one electrode to the neighboring electrode. The border profile does not approximate a linear path, thereby providing a larger maximum slide angle between the electrodes when compared with conventional multi-electrode capacitive touch interfaces.

<FIG> illustrate examples of wearable audio devices that may incorporate the teachings of the various implementations. These examples are not intended to be limiting.

<FIG> is a schematic depiction of a first example wearable audio device <NUM>. In this example, the wearable audio device <NUM> is an audio headset <NUM> having at least one earbud (or, in-ear headphone) <NUM>. Two earbuds <NUM> are illustrated in this example. While the earbuds <NUM> are shown in a "true" wireless configuration (i.e., without tethering between earbuds <NUM>), the audio headset <NUM> could also include a tethered wireless configuration (whereby the earbuds <NUM> are connected via wire with a wireless connection to a playback device) or a wired configuration (whereby at least one of the earbuds <NUM> has a wired connection to a playback device). Each earbud <NUM> is shown including a body <NUM>, which can include a casing formed of one or more plastics or composite materials. The body <NUM> can include a nozzle <NUM> for insertion into a user's ear canal entrance, a support member <NUM> for retaining the nozzle <NUM> in a resting position within the user's ear, and an outer casing <NUM> for housing electronics <NUM>, including components of a capacitive touch interface <NUM>. In some cases, separate, or duplicate sets of electronics <NUM> are contained in portions of the earbuds <NUM>, e.g., each of the respective earbuds <NUM>. However, certain components described herein can also be present in singular form.

<FIG> depicts an additional example wearable audio device <NUM>, including audio eyeglasses <NUM>. As shown, the audio eyeglasses <NUM> can include a frame <NUM> having a lens region <NUM> and a pair of arms <NUM> extending from the lens region <NUM>. As with conventional eyeglasses, the lens region <NUM> and arms <NUM> are designed for resting on the head of a user. The lens region <NUM> can include a set of lenses <NUM>, which can include prescription, non-prescription and/or light-filtering lenses, as well as a bridge <NUM> (which may include padding) for resting on the user's nose. Arms <NUM> can include a contour <NUM> for resting on the user's respective ears. Contained within the frame <NUM> (or substantially contained, such that a component can extend beyond the boundary of the frame) are electronics <NUM> and other components for controlling the audio eyeglasses <NUM> according to particular implementations. Electronics <NUM> can include portions of a capacitive touch interface <NUM>, as described with respect to the wearable audio devices <NUM> herein. In some cases, separate, or duplicate sets of electronics <NUM> are contained in portions of the frame, e.g., each of the respective arms <NUM> in the frame <NUM>. However, certain components described herein can also be present in singular form.

<FIG> depicts another wearable audio device <NUM>, including around-ear headphones <NUM>. Headphones <NUM> can include a pair of earcups <NUM> configured to fit over the ear, or on the ear, of a user. A headband <NUM> spans between the pair of earcups <NUM> and is configured to rest on the head of the user (e.g., spanning over the crown of the head or around the head). The headband <NUM> can include a head cushion <NUM> in some implementations. Stored within one or both of the earcups <NUM> are electronics <NUM> and other components for controlling the headphones <NUM> according to particular implementations. Electronics <NUM> can include portions of a capacitive touch interface <NUM>, as described with respect to the wearable audio devices <NUM> herein. It is understood that a number of wearable audio devices described herein can utilize the features of the various implementations, and the wearable audio devices <NUM> shown and described with reference to <FIG> are merely illustrative.

<FIG> shows a schematic depiction of the electronics <NUM> contained (at least partially) within the wearable audio devices <NUM> (e.g., as shown in <FIG>), along with components of the capacitive touch interface (CTI) <NUM>. It is understood that one or more of the components in electronics <NUM> may be implemented as hardware and/or software, and that such components may be connected by any conventional means (e.g., hard-wired and/or wireless connection). It is further understood that any component described as connected or coupled to another component in the wearable audio device <NUM> or other systems disclosed according to implementations may communicate using any conventional hard-wired connection and/or additional communications protocols. In some cases, communications protocol(s) can include a Wi-Fi protocol using a wireless local area network (LAN), a communication protocol such as IEEE <NUM> b/g a cellular network-based protocol (e.g., third, fourth or fifth generation (<NUM>, <NUM>, <NUM> cellular networks) or one of a plurality of internet-of-things (IoT) protocols, such as: Bluetooth, BLE Bluetooth, ZigBee (mesh LAN), Z-wave (sub-GHz mesh network), 6LoWPAN (a lightweight IP protocol), LTE protocols, RFID, ultrasonic audio protocols, etc. In various particular implementations, separately housed components in wearable audio device <NUM> are configured to communicate using one or more conventional wireless transceivers.

As shown in <FIG>, electronics <NUM> contained within the audio headset <NUM> (<FIG>) can include a transducer <NUM> and a power source <NUM>. In certain implementations, the electronics <NUM> can further include an inertial measurement unit (IMU) <NUM> for detecting movement of the wearable audio device <NUM> and enabling particular control functions. In various implementations, the power source <NUM> is connected to the transducer <NUM>, and can additionally be connected to the IMU <NUM>. Each of the transducer <NUM>, power source <NUM> and IMU <NUM> are connected with a controller <NUM>, which is configured to perform control functions according to various implementations described herein. Electronics <NUM> can include other components not specifically depicted in the accompanying FIGURES, such as communications components (e.g., a wireless transceiver (WT)) configured to communicate with one or more other electronic devices connected via one or more wireless networks (e.g., a local WiFi network, Bluetooth connection, or radio frequency (RF) connection), and amplification and signal processing components. It is understood that these components or functional equivalents of these components can be connected with, or form part of, the controller <NUM>.

The transducer <NUM> can include at least one electroacoustic transducer for producing an acoustic output into, or proximate, the ears of a user. In certain implementations (e.g., in the audio eyeglasses example of <FIG>), each transducer <NUM> can include a dipole loudspeaker with an acoustic driver or radiator that emits front-side acoustic radiation from its front side, and emits rear-side acoustic radiation to its rear side. The dipole loudspeaker can be built into the housing, frame or casing of the wearable audio device <NUM>, and may be configured for the particular form factor of the wearable audio device <NUM>.

The IMU <NUM> can include a microelectromechanical system (MEMS) device that combines a multi-axis accelerometer, gyroscope, and/or magnetometer. It is understood that additional or alternative sensors may perform functions of the IMU <NUM>, e.g., an optical-based tracking system, accelerometer, magnetometer, gyroscope or radar for detecting movement as described herein. The IMU <NUM> can be configured to detect changes in the physical location/orientation of the wearable audio device <NUM>, and provide updated sensor data to the controller <NUM> in order to indicate a change in the location/orientation of the wearable audio device <NUM>. However, it is understood that the electronics <NUM> could also include one or more optical or visual detection systems located at the wearable audio device <NUM> or another connected device configured to detect the orientation of the wearable audio device <NUM>.

The power source <NUM> to the transducer <NUM> can be provided locally (e.g., with a battery proximate each transducer <NUM>), or a single battery can transfer power via wiring (not shown) that passes through the frame or housing of the wearable audio device <NUM>, e.g., depending upon the form factor of the particular wearable audio device <NUM>. The power source <NUM> can be used to control operation of the transducer <NUM>, according to various implementations.

The controller <NUM> can include conventional hardware and/or software components for executing program instructions or code according to processes described herein. For example, controller <NUM> may include one or more processors, memory, communications pathways between components, and/or one or more logic engines for executing program code. Controller <NUM> can be coupled with other components in the electronics <NUM> via any conventional wireless and/or hardwired connection which allows controller <NUM> to send/receive signals to/from those components and control operation thereof.

Controller <NUM> is shown coupled with a printed circuit board (PCB) <NUM>, which in turn is coupled with the capacitive touch interface <NUM> (<FIG>). In some case, the PCB <NUM> and/or components of the capacitive touch interface <NUM> are enclosed in a common housing with the electronics <NUM>, however, these components can be physically separated by one or more partitions in other implementations. The controller <NUM> is configured to receive touch-based commands from the capacitive touch interface <NUM> in order to control operation of the wearable audio device <NUM>. For example, a user can provide a touch command at the capacitive touch interface <NUM> in order to power the wearable audio device <NUM> on or off, switch between playback sources, switch tracks or segments within a playback source, toggle through a menu of playback options, etc..

The capacitive touch interface <NUM> is shown including a contact surface <NUM> for receiving the touch command (e.g., from a user such as a human user), and a set of at least two electrodes <NUM> underlying the contact surface <NUM> for detecting the touch command at the contact surface <NUM>. Three electrodes <NUM> are illustrated in a cross-sectional view of the capacitive touch interface <NUM> in <FIG>, however, it is understood that any number of electrodes <NUM> greater than (<NUM>) can form part of the interface. Electrodes <NUM> can include a sensor pad, and can be connected through the PCB <NUM> to the controller <NUM> by one or more via and/or trace connections to an I/O pin coupled with the controller <NUM>. Electrodes <NUM> can be surrounded or otherwise isolated by a ground hatch <NUM>. As is known in the art, when a user (e.g., a user's finger) touches the contact surface of a capacitive touch interface (e.g., contact surface <NUM> of capacitive touch interface <NUM>), it forms a simple parallel plate capacitor, whose digital value is measured and used to detect presence at the particular electrode and/or movement across electrodes (such as in a swiping motion).

Having two or more electrodes permits detection of movement across the interface <NUM>, significantly increasing the number of available commands from a single-electrode interface. While conventional capacitive touch interfaces use multiple electrodes to detect movement across an interface, these conventional electrode configurations include electrodes separated from neighboring electrodes by linear borders. That is, these conventional interfaces have electrodes with border profiles that are linear or approximate a linear border.

<FIG> illustrates an example plan view of electrodes <NUM> underlying the contact surface <NUM> of <FIG>. As will be described further herein, various configurations of electrodes <NUM> are possible according to the disclosed implementations, only a few of which are illustrated as examples. <FIG> shows an approximately circular or elliptical shaped contact surface <NUM>, defined by a perimeter <NUM>. In this example implementation, the set of (two or more) electrodes are shaped such that neighboring electrodes 470a, 470b, 470c in the set share a border 520a, 520b having an arcuate profile across the contact surface. That is, each border 520a, 520b contacts the perimeter <NUM> at two distinct locations 540a, 540b and has a non-linear, arcuate profile. More particularly, the border 520a, 520b between adjacent electrodes 470a, 470b and 470b, 470c at the contact surface <NUM> follows an arcuate path (and does not follow a linear path) from its first point of contact with the perimeter <NUM> (location 540a) to its second point of contact with the perimeter <NUM> (location 540b). In certain implementations, the arcuate profiles can have inverted arc directions with respect to one another (e.g., arc directions opposing one another).

However, as shown with respect to the example plan view of perimeter <NUM> in <FIG>, electrodes <NUM> (neighboring electrodes 610a, 610b, 610c) can be separated by borders 620a, 620b with arcuate profiles having a common arc direction with respect to the perimeter <NUM>. In certain implementations, these borders 620a, 620b have an equal or approximately equal arc radius, however, these borders 620a, 620b may also have distinct arc radii. These borders may span from a first point of contact with perimeter <NUM> (location 640a) to a second point of contact with perimeter <NUM> (location 640b).

<FIG> illustrates the three electrodes 470a, 470b and 470c of <FIG> in isolated plan view, illustrating the arcuate sidewalls <NUM> of each of those electrodes. In particular, as shown in this plan view, electrode 470a has an arcuate convex sidewall 710a and an opposing, arcuate concave sidewall 710b, while electrode 470b has two opposing arcuate convex sidewalls 710a and electrode 470c has an arcuate convex sidewall 710a and an opposing, arcuate concave sidewall 710b. As illustrated in <FIG> (as well as <FIG> and <FIG>), the sidewalls of directly neighboring electrodes (e.g., 470a, 470b) can have complementary profiles.

Returning to <FIG> and <FIG>, in various implementations, the contact surface <NUM> is sized according to the form factor of the wearable audio device <NUM> (<FIG>). In particular cases, this means the contact surface <NUM> will be smaller than the broadest surface on the wearable audio device <NUM>. Additionally, the contact surface <NUM> is located on a surface which provides the user with relatively easy access to perform touch commands. For example, in the case of the earbuds <NUM> in <FIG>, the contact surface <NUM> is no larger than the outer surface of the housing <NUM> (e.g., a face of outer housing <NUM>). In one particular example, the contact surface <NUM> (as defined by perimeter <NUM>) has an area of less than approximately <NUM>-<NUM> square millimeters (mm) (e.g., a circular contact surface with a radius of approximately <NUM>). However, this is only one example range for the size of contact surface <NUM>.

The range of at which a sliding (also called swiping) command can be detected across adjacent electrodes is referred to as the slide angle of the interface. In various implementations, the contact surface <NUM> is aligned on the wearable audio device <NUM> to detect a touch command across adjacent electrodes (e.g., 470a, 470b, 470c or 610a, 610b, 610c) using a vertical or horizontal sliding (or swiping) gesture (relative to a ground surface). In this sense, the contact surface <NUM> is designed to enable the user to easily slide/swipe in a direction to initiate particular commands.

Due to the wearable nature of the audio device <NUM> upon which the capacitive touch interface <NUM> is located, the user is often not looking at the contact surface <NUM> when making a touch command (e.g., swiping gesture) at the interface. Additionally, due to the wearable nature of the audio device <NUM>, the wearable audio device <NUM> is often oriented in a direction that is not exactly normal to the ground or other flat surface. This can make it difficult for users to effectively perform their intended directionally-based touch commands. For example, a user wearing the earbuds <NUM> shown in <FIG> may intend to make a vertical swiping gesture (contacting at least two electrodes) across the contact surface <NUM>, but may in fact be swiping at an angle which deviates significantly from the vertical orientation of the contact surface <NUM> on the earbuds <NUM> e.g., due to the fit of the earbuds in her ear, the orientation of her head relative to the ground and/or the trajectory of her finger as she makes the swiping gesture (without seeing the contact surface <NUM>).

As descried herein, conventional capacitive touch interfaces with multiple electrodes capable of detecting swiping or sliding gestures have linear electrode borders along the contact surface, or borders approximating a straight line (e.g., sinusoids or sawtooth borders tightly centered around a straight line) along the contact surface. These linear borders limit the slide angle of conventional interfaces. That is, in the case of linear borders, the end points of those borders geometrically define the range of sliding angles. This limits the available slide angle of those conventional interfaces. This narrow slide angle can be particularly limiting where the capacitive touch interface has a small contact surface area, where the user does not see the interface when making a command gesture and where the device on which the interface is located is not uniformly aligned. These challenges can all exist in wearable audio devices.

In comparison to conventional capacitive touch interfaces, the contact surface (e.g., contact surface <NUM> in <FIG> and <FIG>) disclosed according to various implementations can provide an enhanced slide angle (also referred to as a maximum slide angle) for touch commands (e.g., sliding or swiping gestures). For example, the electrode configurations shown in <FIG> and <FIG> can provide a maximum slide angle (αs) for a touch command that is greater than the maximum slide angle for conventional capacitive touch interfaces. In one particular example implementation, as discussed with reference to <FIG> and <FIG>, the maximum slide angle (αs) for a touch command is greater than a reference slide angle for a reference contact surface having electrodes with border profiles that are linear or approximate a linear border. This slide angle can be indexed to the ground surface, or another surface substantially parallel with the ground surface. In the example of a vertical swiping gesture by a user (vertical relative to ground), the contact surface <NUM> provides a wide maximum slide angle (αs) to detect such a gesture. This can be particularly beneficial in the case of the wearable audio device <NUM>, which may be positioned in a number of ways depending upon the user's body or head position, and may not be directly visible to the user.

While the perimeter <NUM> shown in the example implementations of contact surface <NUM> is shaped as a circular or an ellipse, it is understood that this perimeter can take other forms. For example, <FIG> illustrate additional implementations including electrodes arranged below a contact surface defined by a non-circular shaped perimeter, e.g., a rectangular-shaped perimeter. In particular, <FIG> shows an example implementation with electrodes <NUM> (810a, 810b, 810c) arranged below a contact surface <NUM> defined by a rectangular-shaped perimeter <NUM>. In these cases, the border <NUM> between adjacent electrodes <NUM> can take the form of any electrode border described herein. Additionally, one or more sidewalls of the electrodes <NUM> may have a linear profile relative the contact surface <NUM>, e.g., sidewalls 850a and 850b of electrodes 810a and 810c.

In additional implementations, the border between adjacent electrodes can take other forms which are non-linear and do not approximate a linear path. For example, <FIG> and <FIG> depict examples of electrodes 910a, 910b, 910c and electrodes 1010a, 1010b, 1010c (<FIG>) within the rectangular-shaped perimeter <NUM>. In both of these example implementations, borders between electrodes 910a, 910b, 910c and 1010a, 1010b, 1010c have a piecewise profile approximating a non-linear path across the contact surface <NUM>.

With particular reference to <FIG>, electrodes 910a, 910b, 910c are separated by borders 920a, 920b each having a piecewise profile relative to the contact surface <NUM>. As with other example implementations illustrated herein, the piecewise profiles of borders 920a, 920b may have a same or similar orientation (as shown), or may have an inverted orientation relative to one another. In any case, the piecewise profiles each include at least two continuous segments 940a, 940b with distinct orientations (e.g., angles relative to one another or the perimeter <NUM>) that approximate a non-linear path across the contact surface <NUM>. That is, the piecewise profile <NUM> includes distinct segments 940a, 940b that collectively span an entire dimension of the contact surface <NUM> (e.g., a width as shown in <FIG>) but do not form a single linear path from one end <NUM> to another end <NUM>. The example chevron-shaped profile in <FIG> is only one example of a piecewise profile used to form borders according to various implementations. <FIG> illustrates two additional example piecewise profiles separating distinct electrodes. As illustrated in <FIG>, in some cases, neighboring electrodes 1010a, 1010b, 1010c can be separated by borders <NUM> and <NUM> having distinct profile types. For example, two distinct piecewise profiles are illustrated in borders <NUM> and <NUM>, where profile <NUM> includes a meandering profile and profile <NUM> includes a saw tooth-shaped profile along an arcuate path. It is understood that the meandering profile can take any piecewise form approximating a non-linear path across the contact surface <NUM> (from one end <NUM> to another end <NUM>). Additionally, other piecewise profiles can be employed according to various implementations, e.g., a sinusoidal profile approximating an arcuate path, or an uneven zig-zag profile approximating an arcuate path.

It is further understood that the piecewise profile example implementations shown and described with respect to <FIG> and <FIG> are equally applicable to contact surfaces having non-rectangular shapes (e.g., contact surface <NUM> or other rounded or ellipse-shaped contact surfaces).

For example, <FIG> and <FIG> illustrate the comparison between contact surfaces shown and described herein and a reference contact surface <NUM> (<FIG>) in terms of maximum slide angle (αs) for gesture detection. <FIG> illustrates one example reference contact surface <NUM>, while <FIG> illustrates an example contact surface <NUM> according to various implementations. Both the reference contact surface <NUM> and the contact surface <NUM> have a rectangular-shaped perimeter (as discussed according to various implementations herein). Three electrodes are shown in each of these examples. However, in contrast to the reference contact surface <NUM>, contact surface <NUM> includes electrodes <NUM> that share a border having an arcuate profile <NUM> across the contact surface <NUM>. The reference contact surface <NUM>, as shown, has electrodes <NUM> with border profiles <NUM> that are linear.

The center of each contact surface <NUM>, <NUM>, is marked with a point (C), while two distinct linear swiping (gesture) directions are indicated by the bold arrows crossing through the center (C). In this example configuration, each linear swiping action travels at least a distance (d) within each electrode zone to be detected by the respective electrodes <NUM>, <NUM>. In this example, when the swiping action is linear and the distance travelled within each zone meets the minimum distance (e.g., distance (d)), the maximum slide angle (αs) for each configuration is significantly distinct. That is, the maximum slide angle (αs) for contact surface <NUM> in <FIG> is shown as X degrees, while the maximum slide angle (αs) for contact surface <NUM> in <FIG> is shown as the larger angle, indicated as Y degrees. This greater maximum slide angle, as described herein, is caused by the electrode and electrode border shapes shown and described according to various particular implementations. This comparison shown in <FIG> and <FIG> is intended merely to illustrate various features of the disclosed implementations when compared with conventional configurations. These figures are not intended to limit the various implementations described herein.

In any case, as noted herein the wearable audio device <NUM> including a capacitive touch interface according to various implementations can improve the maximum slide angle in touch commands for such devices, significantly improving the user experience when compared with conventional devices.

The functionality described herein, or portions thereof, and its various modifications (hereinafter "the functions") can be implemented, at least in part, via a computer program product, e.g., a computer program tangibly embodied in an information carrier, such as one or more non-transitory machine-readable media, for execution by, or to control the operation of, one or more data processing apparatus, e.g., a programmable processor, a computer, multiple computers, and/or programmable logic components.

Actions associated with implementing all or part of the functions can be performed by one or more programmable processors executing one or more computer programs to perform the functions of the calibration process. All or part of the functions can be implemented as, special purpose logic circuitry, e.g., an FPGA and/or an ASIC (application-specific integrated circuit). Components of a computer include a processor for executing instructions and one or more memory devices for storing instructions and data.

Elements of figures are shown and described as discrete elements in a block diagram. These may be implemented as one or more of analog circuitry or digital circuitry. Alternatively, or additionally, they may be implemented with one or more microprocessors executing software instructions. The software instructions can include digital signal processing instructions. Operations may be performed by analog circuitry or by a microprocessor executing software that performs the equivalent of the analog operation. Signal lines may be implemented as discrete analog or digital signal lines, as a discrete digital signal line with appropriate signal processing that is able to process separate signals, and/or as elements of a wireless communication system.

When processes are represented or implied in the block diagram, the steps may be performed by one element or a plurality of elements. The steps may be performed together or at different times. The elements that perform the activities may be physically the same or proximate one another, or may be physically separate. One element may perform the actions of more than one block. Audio signals may be encoded or not, and may be transmitted in either digital or analog form. Conventional audio signal processing equipment and operations are in some cases omitted from the drawings.

In various implementations, components described as being "coupled" to one another can be joined along one or more interfaces. In some implementations, these interfaces can include junctions between distinct components, and in other cases, these interfaces can include a solidly and/or integrally formed interconnection. That is, in some cases, components that are "coupled" to one another can be simultaneously formed to define a single continuous member. However, in other implementations, these coupled components can be formed as separate members and be subsequently joined through known processes (e.g., soldering, fastening, ultrasonic welding, bonding). In various implementations, electronic components described as being "coupled" can be linked via conventional hard-wired and/or wireless means such that these electronic components can communicate data with one another. Additionally, sub-components within a given component can be considered to be linked via conventional pathways, which may not necessarily be illustrated.

Claim 1:
A wearable audio device (<NUM>) comprising:
an acoustic transducer (<NUM>) comprising a sound-radiating surface for providing an audio output;
a controller (<NUM>) coupled with the acoustic transducer;
a printed circuit board (<NUM>), PCB, coupled with the controller; and
a capacitive touch interface (<NUM>) coupled with the PCB, the capacitive touch interface comprising:
a contact surface (<NUM>) for receiving a touch command corresponding to a linear swiping gesture of a finger of a user along the contact surface; characterised by
a set of at least two electrodes (<NUM>) underlying the contact surface for detecting the touch command at the contact surface, wherein neighboring electrodes in the set share a border comprising an arcuate profile across the contact surface so as to enhance slide angle detection of the touch command.