Abstract: It is provided a method comprising the steps of: obtaining a first sample point and a second sample point; transforming the first sample point and the second sample point by setting the I value of a first transformed sample point to the Q value of the obtained first sample point, setting the Q value of the first transformed sample point to the inverse of the I value of the obtained first sample point, setting the I value of a second transformed sample point to the inverse of the Q value of the obtained second sample point, setting the Q value of the second transformed sample point to the I value of the obtained second sample point; determining the phase difference between the first sample point and the second sample point; and determining the position of the mobile key device based on the phase differences.

Abstract: A system for managing, storing and providing shared digital content to a group of users in a multi-platform environment, comprising a cloud storage component configured to store digital content items that are shared by members in a user relationship defined group, and a cloud service component configured to provide one of the digital content items to a first platform for a first member of the user relationship defined group in a format suitable for the first platform and to a second platform for a second member of the user relationship defined group in a format suitable for the second platform, wherein the first platform and the second platform are different platforms.

Abstract: In an embodiment an apparatus includes a display panel and a speaker module. The panel has a display layer for displaying images and defines a plurality of apertures penetrating through at least the display layer. The speaker module includes a diaphragm arranged substantially parallel to the display layer. Sound from the speaker diaphragm is directed outside a device through the apertures and the display layer is configured for displaying at least one virtual image in relation to generated sound waves wherein the display panel is acoustically transparent.

Abstract: The technology disclosed relates to enhancing the fields of view of one or more cameras of a gesture recognition system for augmenting the three-dimensional (3D) sensory space of the gesture recognition system. The augmented 3D sensory space allows for inclusion of previously uncaptured of regions and points for which gestures can be interpreted i.e. blind spots of the cameras of the gesture recognition system. Some examples of such blind spots include areas underneath the cameras and/or within 20-85 degrees of a tangential axis of the cameras. In particular, the technology disclosed uses a Fresnel prismatic element and/or a triangular prism element to redirect the optical axis of the cameras, giving the cameras fields of view that cover at least 45 to 80 degrees from tangential to the vertical axis of a display screen on which the cameras are mounted.

Abstract: The operating unit for a vehicle comprises a housing with an operating element on the front side, wherein the operating element has a display with a display surface and a cover plate, which defines an operating surface of the operating element, and has at least one projection region projecting laterally over the display, and is elastically laterally moveably mounted on and/or in the housing. An actuator is arranged below the cover plate, said actuator having a drive and a control element driven by the drive. The operating unit is also provided with an elastic actuation arm which protrudes from the cover plate and which is mechanically acted upon by the control element of the actuator at a force application point of the actuation arm.

Abstract: A detection method of a three-dimensional touch module includes: step S1, providing an input signal to a transmitting electrode layer; step S2, outputting a first output signal and transmitting the first output signal to a control module by a two-dimensional inputting assembly, and outputting a second output signal and transmitting the second output signal to the control module by a pressure sensing assembly; and step S3, determining, by the control module, a touch position according to the first output signal and a pressure value according to the second output signal. A three-dimensional touch module includes: a cover plate; a two-dimensional inputting assembly disposed under the cover plate and configured to output a first output signal; a pressure sensing assembly disposed under the cover plate and configured to output a second output signal; and a transmitting electrode layer disposed between the two-dimensional inputting assembly and the pressure sensing assembly.

Abstract: A display device includes a display panel, a bracket disposed on a first surface of the display panel, and a first vibrating device disposed between the first surface of the display panel and a first surface of the bracket which faces the first surface of the display panel. The first vibrating device is configured to output a first sound and provide a haptic feedback by vibrating the display panel and the bracket.

Abstract: An ultrasonic induction circuit is provided, a first electrode of an ultrasonic sensor is electrically connected with a first terminal of the ultrasonic sensing circuit, a second electrode is electrically connected with a second terminal of a first potential supply sub-circuit, and the first terminal of the first potential supply sub-circuit is electrically connected with a first potential supply end. A gate of M1 is electrically connected with the second electrode and the second terminal of the compensation sub-circuit. The second electrode is electrically connected with the first terminal of the compensation sub-circuit. The first electrode is coupled to the second potential supply end. The first terminal of the signal output sub-circuit is electrically connected to the second electrode of the first transistor, and the second terminal is electrically connected to the second terminal of the ultrasonic induction circuit.

Abstract: A method for controlling a plurality of ultrasonic transducers in a fingerprint sensing system that comprises a cover plate having a sensing surface configured to be touched by a finger, and a plurality of ultrasonic transducers located at the periphery of the cover plate and configured to transmit an acoustic signal propagating in the cover plate, receive an ultrasonic signal having interacted with an object in contact with the sensing surface, and to determine properties of the object based on the received ultrasonic signal. The method comprises: in response to a first input, controlling the plurality of transducers such that at least a portion of the sensing surface has a first feature detection resolution; and in response to a second input, controlling the plurality of transducers such that at least a portion of the sensing surface has a second feature detection resolution, different from the first feature detection resolution.

Abstract: A physical disturbance sensor includes a plurality of piezoresistive elements configured in a resistive bridge configuration. A signal transmitter is electrically connected to the physical disturbance sensor and configured to send an encoded signal to the piezoresistive elements of the resistive bridge configuration. A signal receiver is electrically connected to the piezoresistive elements and configured to receive a signal from the physical disturbance sensor. The received signal from the physical disturbance sensor is correlated with the sent encoded signal in determining a measure of physical disturbance.

Abstract: A wearable device equipped with sensors or transducers capable of detecting a vibration propagating through two different mediums. In some embodiments, the two mediums are air and a surface contacted by a user. In such an embodiment, the sensors or transducers include a microphone and an accelerometer. In some embodiments, the device may perform some or all of the signal processing and/or logic used to determine that a contact occurred and the location of the contact using a processor programmed with a set of computer-executable instructions. In some embodiments, the device may transmit data or signals to a processor located in a different device, such as a mobile phone or artificial reality headset, for signal processing and/or the execution of logic.

Abstract: Improving the accuracy of ultrasonic touch sensing via the reduction, elimination and/or rejection of parasitic ultrasonic reflections caused by unintended touches is disclosed. The adverse effects of these parasitic reflections can be mitigated by disrupting the symmetry of the true reflections (from the intended touch) and the parasitic reflections (from unintended touches) so that the true touch can be disambiguated from unintended touches. Identification of the true touch can then enable accurate touch localization.

Abstract: A polarizer disposed between a transducer and a surface in which acoustic waves propagate can be used to filter out certain types of acoustic energy. For example, the polarizer can be used with a shear-polarized transducer to pass shear waves and filter out compressional waves that may interact with water, thereby improving water rejection. In some examples, the polarizer can include one or more layers of piezoelectric material with a poling direction different than (e.g., orthogonal to) the poling direction of the transducer. Energy of compressional waves may be extracted by one or more external electric circuits. In some examples, the polarizer can be a magneto-elastic polarizer. In some examples, the polarizer can be a mechanical polarizer.

Abstract: Acoustic touch and/or force sensing system architectures and methods for acoustic touch and/or force sensing can be used to detect a position of an object touching a surface and an amount of force applied to the surface by the object. The position and/or an applied force can be determined using time-of-flight (TOF) techniques, for example. Acoustic touch sensing can utilize transducers (e.g., piezoelectric) to simultaneously transmit ultrasonic waves along a surface and through a thickness of a deformable material. The location of the object and the applied force can be determined based on the amount of time elapsing between the transmission of the waves and receipt of the reflected waves. In some examples, an acoustic touch sensing system can be insensitive to water contact on the device surface, and thus acoustic touch sensing can be used for touch sensing in devices that may become wet or fully submerged in water.

Abstract: A touch panel has a substrate having first and second surfaces, and defines a touch surface. A first portion of a touch system includes a first plurality of echelons on the first surface in a first array along a first centerline. Each echelon is formed at an angle to the first centerline, and a first shear transducer assembly on the edge of the substrate that generates a shear wave in a source wave mode in a first direction along the first centerline. A second portion of the touch system includes a second plurality of echelons on the first surface in a second array along a second centerline, each echelon at a second angle to the second centerline. The second centerline is orthogonal to the first. A second shear transducer assembly is mounted on the edge and generates a shear wave in a source wave mode in a second direction along the second centerline. The first sensing mode is different from the second sensing mode.

Abstract: The operating unit for a device, in particular for a vehicle component, is provided with a housing (10) that has a control panel (12) and is provided for attaching in an apparatus, in particular a vehicle dashboard or vehicle center console, the control panel (12) being elastically mounted on the housing (10). Furthermore provided is an actuator (16) for mechanically exciting exclusively the control panel (12) when use of the control panel (12) is detected, the control panel forming the front side of a touch-sensitive touch panel (13). Finally, the operating unit also comprises a vibration compensation mass (20) that is mechanically excitable by the or by an actuator (16) when use of the control panel (12) is detected and is elastically mounted in and/or on the housing (10) and is movable to essentially compensate for a movement of the housing (10) when activating the actuator (16) that can mechanically excite the control panel (12).

Abstract: A method for detecting the presence and/or determine a position of an object on a measurement surface of an electronic device. The process includes: providing oscillating signal(s) at input points which are different and spaced from the array of electrodes in a detection area of the measurement surface; receiving oscillating signal(s) having passed through the array, which defines a transfer function of the signals, in output point(s) which are different and spaced from the array of electrodes in a detection area of the measurement surface; measuring a coupling or an attenuation induced by the presence on one or more oscillating signals passing through the array of electrodes of an object placed on the measurement surface in order to determine the position of the object in the detection area of the measurement surface depending on the modification of the transfer function of the array of electrodes.

Abstract: A display device and an electronic device including the same are provided. The display device includes a cover glass, a substrate disposed under the cover glass, a display light emitting layer disposed between the cover glass and the substrate and including a plurality of pixels, a fingerprint sensor layer disposed between the display light emitting layer and the substrate to generate sound waves in a specified frequency band in connection with obtaining of fingerprint information of a user's body in contact with a portion of the cover glass, and a thin film transistor (TFT) circuit layer disposed between the fingerprint sensor layer and the substrate and including a plurality of first transistors related to driving of the plurality of pixels and a plurality of second transistors related to driving of the fingerprint sensor layer.

Abstract: A fingerprint identification device, a driving method thereof, and a display device are disclosed. The fingerprint identification device includes: a receiving electrode layer, a piezoelectric material layer, and a drive electrode layer. The piezoelectric material layer is between the receiving electrode layer and the drive electrode layer, the piezoelectric material layer is configured to emit ultrasonic waves under an excitation of at least a drive voltage, and is further configured to convert ultrasonic waves, which are emitted by the piezoelectric material layer and reflected by a fingerprint to be detected, into electrical signals; the drive electrode layer is configured to receive the drive voltage and a first fixed voltage simultaneously, and the receiving electrode layer is configured to output the electrical signals while receiving a second fixed voltage; the electrical signals are used for obtaining a fingerprint image.

Abstract: A patient support apparatus comprises a patient support surface for patients. The patient support apparatus comprises a user input device, a controller, and an ultrasonic generator system. The controller is configured to control the ultrasonic generator system to provide haptic sensations to the user. The haptic sensations, in some cases, provides tactile stimuli to a user associated with a virtual button.

Abstract: The present invention provides an ultrasonic fingerprint recognition module and a display panel. Advantages of the present invention are that a vibration absorbing layer can absorb mechanical energy of a piezoelectric thin film layer such that a number of cycles of later ultrasound is significantly reduces to extremely increase a vertical resolution of ultrasound fingerprint recognition and overall recognition effect and precision.

Abstract: An electronic apparatus comprises a display module configured to display an image and including a touch electrode layer, a vibration generator including a vibration element on a rear surface of the display module, a touch driver configured to generate touch data by sensing a touch through the touch electrode layer, the touch data including noise information, an audio processor configured to supply an audio signal to the vibration element, and a controller configured to control a driving frequency of the audio signal based on the touch data.

Abstract: A display device for a vehicle includes a stretchable display panel and a touch sensor on a first surface of the stretchable display panel and configured to sense a user's touch. The stretchable display panel includes a plurality of pixels and has a button display area and a display area adjacent the button display area. The stretchable display panel is integrally arranged on a center fascia of the vehicle that as a plurality of curved surfaces, and a step is defined between the button display area and the adjacent display area.

Abstract: A display device includes a display panel, a main vibrator disposed on the display panel configured to generate a main vibration wave, and a plurality of sub-vibrators disposed on the display panel and spaced apart from the main vibrator and configured to the plurality of sub-vibrators configured to generate sub-vibration waves, respectively, wherein the plurality of sub-vibrators includes a first sub-vibrator disposed at a first distance from the main vibrator in a plan view, the first sub-vibrator being configured to generate a first sub-vibration wave; and a second sub-vibrator disposed at a second distance from the main vibrator in the plan view, the second sub-vibrator being configured to generate a second sub-vibration wave having a phase different from the first sub-vibration wave, and, wherein the second distance is different from the first distance.

Abstract: A system for determining the location of a mobile receiver unit includes static transmitter units, each including a respective clock which it uses to transmit a positioning signal according to a respective transmission schedule. The mobile receiver unit receives a positioning signal from any of the static transmitter units. A first processing means uses information relating to the received positioning signal to determine the location of the mobile receiver unit. A second processing means uses information relating to a respective drift and/or offset of each of the clocks of the static transmitter units to generate transmission schedules for the static transmitter units. Each transmission schedule instructs a respective static transmitter unit to transmit a positioning signal at one or more scheduled times according to the clock of the static transmitter unit.

Abstract: A processing device includes a controller including hardware. The controller is configured to execute: generating an ultrasound image based on an ultrasound signal acquired by an ultrasound probe, the ultrasound probe being configured to transmit an ultrasonic wave to a subject that is an observation target and receive an ultrasonic wave reflected by the subject; generating shift information including a shift direction of a display area of the ultrasound image displayed on a display unit in accordance with a command position with respect to the ultrasound image; shifting the ultrasound image in accordance with the shift information; and generating a character image indicating an area targeted for a process performed on the ultrasound image in relation to the command position in the ultrasound image after being shifted.

Abstract: An operation determination device determines an operation performed by a user in a non-contact manner on a display image. An image acquisition unit acquires a photographed image of the user, and an image processing unit performs image processing on the photographed image and determines the position of the line-of-sight of the user, the position of the fingertip, and the movement of the fingertip with respect to the display image. The image processing unit includes a first processing unit configured to detect the positions of the eyes and fingertip of the user in the photographed image, and a second processing unit that calculates the position of the user's sight line and fingertip with respect to the display surface based on the detected positions of the user's eyes and the fingertip in the photographed image and that determines a movement of the user's fingertip.

Abstract: A sound generator for a display device, including: a first vibration generation unit having a first electrode and a second electrode; a second vibration generation unit having a third electrode and a fourth electrode; and a vibration layer including: a first sub-vibration layer disposed between the first electrode and the second electrode; and a second sub-vibration layer disposed between the third electrode and the fourth electrode, wherein the first vibration generation unit is configured to contract and expand the first sub-vibration layer based on a first driving voltage applied to the first electrode and a second driving voltage applied to the second electrode, and wherein the second vibration generation unit is configured to contract and expand the second sub-vibration layer based on a third driving voltage applied to the third electrode and a fourth driving voltage applied to the fourth electrode.

Abstract: The present invention is a multi-function ultrasonic sensor controller (inc. sensor driver capabilities) capable of authenticating an end-user when placing his/her finger on any am of a device display while further providing haptic feedback, surface roughness and texture rendering, proximity sensing, movement recognition, 3D positioning and remote power transfer for an improved end-user experience. By default, the multi-function ultrasonic sensor controller of the invention is made of a first set of ultrasonic transducers covering the whole screen display area for fingerprint scanning, a second set ultrasonic transducers for haptic feedback, surface and texture roughness rendering, a third set ultrasonic transducers for movement recognition, proximity sensing and 3D localization, and a fourth set of ultrasonic transducers for the reception of remote power transfer through ultrasound waves.

Abstract: A propagating signal transmitted through a propagating medium is received where a detected disturbance to a signal property of the propagating signal is analyzed to detect whether a touch input has been provided. It is determined whether the detected disturbance matches a signature and in the event it is determined that the detected disturbance matches the signature, it is determined that the detected disturbance does not correspond to the touch input.

Abstract: An indicator identifying a force intensity of a touch input provided on a touch input surface is received. It is determined that the touch input is associated with an audio volume control. An audio volume is controlled based at least in part on the indicator identifying the force intensity of the touch input.

Abstract: A vibration control apparatus accepts, from a user, correction information designating the content of correction in vibrating a vibration device, and vibrates the vibration device in accordance with the content of an accepted vibration instruction corrected to reflect the correction information.

Abstract: A physical disturbance sensor includes a plurality of piezoresistive elements configured in a resistive bridge configuration. A signal transmitter is electrically connected to the physical disturbance sensor and configured to send an encoded signal to the piezoresistive elements of the resistive bridge configuration. A signal receiver is electrically connected to the piezoresistive elements and configured to receive a signal from the physical disturbance sensor. The received signal from the physical disturbance sensor is correlated with the sent encoded signal in determining a measure of physical disturbance.

Abstract: A method for adjusting touch sensitivity is disclosed. The method comprises steps of enabling an audio-collecting device to receive one or more original audio data; determining whether an audio parameter of at least one of the one or more original audio data matches at least one pre-stored audio parameter; and adjusting a touch sensitivity of a touch input interface to one of a plurality of pre-stored touch sensitivity in response to the audio parameter of the at least one original audio data matching the at least one pre-stored audio parameter, wherein the pre-stored touch sensitivity corresponds to the at least one pre-stored audio parameter.

Abstract: A fingerprint sensor of an electronic device includes a plurality of acoustic transducers and a signal processor. The plurality of acoustic transducers are arranged on one surface of the plate-like member to surround at least a portion of an outer perimeter of a measuring area of the plate-like member to transmit and receive ultrasonic guided waves. The signal processor recognizes a target object touching a surface of the measuring area through ultrasonic wave tomography that applies a time-reversal process with respect to a signal transmitted from at least one of the plurality of acoustic transducers and a signal received by at least one of the remaining acoustic transducers.

Abstract: A touch pen includes a microphone that detects contact sound generated when a nib contacts an input surface of a touch panel, a voice generator that generates pseudo voice based on the contact sound detected by the microphone, and a voice outputter that outputs the pseudo voice generated by the voice generator.

Abstract: Methods, systems and computer program products for speech and gesture interaction of multiple users with devices using voice activated interfaces are provided herein. A computer-implemented method includes transmitting a pilot signal from a device comprising a voice activated interface, the pilot signal having a frequency, detecting motion of at least one user around the device, associating the detected motion with a gesture, and performing a function in response to the gesture. Detecting the motion includes receiving a reflected signal of the pilot signal caused by the motion of the at least one user, and detecting a shift in the reflected signal from the pilot signal, wherein detecting the shift comprises determining one or more differences between a waveform corresponding to the pilot signal and a waveform corresponding to the reflected signal.

Abstract: The present disclosure relates to a display substrate. The display substrate includes an active region and a non-active region, and a depth camera is disposed in the non-active region. The depth camera includes at least one receiving unit and a plurality of diffractive units. At least a part of the diffractive units includes an infrared light emitting device disposed on the substrate that emits infrared light. The part of the diffractive units includes a diffractive optical element disposed on the infrared light emitting device and used to transmit the infrared light emitted from the infrared light emitting device to an object. The receiving unit includes an infrared photosensitive device disposed on the substrate and used to receive the infrared light reflected by the object.

Abstract: An acoustic biometric touch scanner device and method is disclosed. In one aspect, an acoustic fingerprint sensing device includes an array of ultrasonic transducers configured to transmit an ultrasound signal having a frequency in a range from 50 megahertz (MHz) to 500 MHz. The acoustic fingerprint ultrasonic transducers include a piezoelectric film. The acoustic fingerprint sensing device further includes a receiving surface configured to receive a finger. The acoustic fingerprint sensing device further includes a processor configured to generate an image of at least a portion of a fingerprint of the finger based on a reflection of the ultrasound signal from the finger.

Abstract: Various approaches related to capturing content of erasable boards are discussed herein.

Abstract: A capacitive touch system and a sensing method thereof are disclosed. The capacitive touch system includes a touch panel including a plurality of driving electrodes and a plurality of sensing electrodes; a touch control chip; and an external device configured to transmit data to the touch control chip. In a position detection mode, the touch control chip drives the driving electrodes, reads a sensing signal from the sensing electrodes, and determines a position of a touch according to the sensing signal. In a data receiving mode, the touch control chip receives the data transmitted by the external device after a time delay period. In the capacitive touch system and the sensing method thereof, the position detection mode and the data receiving mode can be sequentially performed by delaying the time period.

Abstract: This relates to system architectures, apparatus and methods for acoustic touch detection (touch sensing) and exemplary applications of the system architectures, apparatus and methods. In some examples, the acoustic touch sensing techniques described herein can be used on a glass surface of a display or touch screen. In some examples, an acoustic touch sensing system can be configured to be insensitive to contact on the device surface by water, and thus acoustic touch sensing can be used for touch sensing in devices that are likely to become wet or fully submerged in water.

Abstract: A display apparatus includes a first substrate; a pixel array layer disposed on the first substrate and defining a display area and a non-display area, and the pixel array layer including a pixel signal line; a second substrate disposed opposite to the first substrate; a display medium disposed between the first substrate and the second substrate; and an ultrasonic element (UE) layer, disposed on the second substrate and including an ultrasonic signal line. Within at least parts of the display area corresponding to the ultrasonic element layer, a projection area on the first substrate by projecting the ultrasonic signal line along the normal direction of the first substrate at least partially overlaps with another projection area on the first substrate by projecting the pixel signal line along the normal direction of the first substrate.

Abstract: The simple gesture control of the user interface can be used by visually impaired or blind people in order to enter telephone numbers or account numbers for example. The user interface and the method constitute a shift from the current paradigm of guiding a user on touchscreens, which has precisely the advantage of the handeye coordination allowed by the touchscreen, wherein a user touches the exact location on the touchscreen where a corresponding selection surface is visualized. Instead, a swiping gesture is supported which can be carried out in any region on the touch-sensitive surface and shifts the focus from one selection surface or virtual button to the next. The swiping gesture can be carried out not just in the horizontal and vertical direction but also in a diagonal direction. Diagonal swiping gestures allow a particularly quick selection of the corresponding virtual buttons.

Abstract: One embodiment provides a method, including: identifying, using an information handling device, a proximate sound source; determining, using a processor, that noise produced by the proximate sound source is duplicated on a conference bridge that a user is connected to and is within an audible range of the user; and preventing, based on the determining, the noise on the conference bridge from reaching the user. Other aspects are described and claimed.

Abstract: A method includes receiving by wireless transmission, a first signal transmitted by a digitizer system. The first signal is configured to define a detection period during which a second signal may be detected by the digitizer system. The method further includes detecting timing of the receiving, detecting a first delay in the receiving due to amplification associated with the receiving, defining timing to transmit the second signal based on the timing of the receiving and the first delay and transmitting the second signal at the timing defined. The second signal is transmitted with a handheld device by wireless transmission and the first delay is detected by the handheld device that is receiving the first signal and transmitting the second signal.

Abstract: Provided are a low-power ultrasound sensor that detects whether an object exists at a high speed, an object detecting method of the ultrasound sensor, and a computer-readable storage medium. The ultrasound sensor may include: a transmitter that outputs a plurality of first ultrasound beams having different frequencies; a receiver that receives a first reflection signal that is output when the output plurality of first ultrasound beams are reflected from an object; and a controller that determines a first area in a space, controls the transmitter to respectively output the plurality of first ultrasound beams to a plurality of first sub-areas that are included in the first area, and determines whether the object is included in each of the plurality of first sub-areas, based on the first reflection signal.

Abstract: A display driving unit circuit, a driving method, a display driving circuit and a display device are provided. The display driving unit circuit includes a pixel driving circuit and a light-emission control signal generation circuit. The light-emission control signal generation circuit is coupled to the pixel driving circuit. The pixel driving circuit is to drive a pixel to emit light. The light-emission control signal generation circuit is to supply a display light-emission control signal to the pixel driving circuit at a display stage to enable the pixel in a displaying mode and supply a fingerprint detection light-emission control signal to the pixel driving circuit at a fingerprint detection stage to enable the pixel in a fingerprint detection light-emission mode at the fingerprint detection stage. The display stage and the fingerprint detection stage are different time periods.

Abstract: Systems and related methods providing for touch sensors using high sensitivity Lamb waves are disclosed herein. A touch controller may comprise circuitry having operating frequency characteristics, including an operating frequency f and a frequency spread ?f; and circuitry configured to minimize effects of dispersion based upon at least one of selected operating frequency characteristics relative to a frequency dependence of a group velocity of propagating waves and a frequency dependent phase error, wherein the touch controller generates an excitation signal.

Abstract: An electronic device (1) such as a cell phone, or a proximity detector for an electronic device (1), has an ultrasound transmitter (5), an ultrasound receiver (6), and a processing system. It transmits an ultrasonic sine-wave signal from the transmitter (5), and receives the ultrasonic sine-wave signal, through air, at the receiver (6). It detects when the frequency of the transmitted signal and a frequency of the received signal satisfy a predetermined difference criterion, and uses this to determine whether to disable or enable a touch or touchless input (2) on the device (1).