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.

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.

A source audio signal to be rendered by a touch input medium is received. A transmitted signal to be propagated through the touch input medium is sent. The transmitted signal includes the source audio signal and a touch location detection signal. An event is indicated, where the touch input medium has been contacted at a location on the touch input medium by a touch contact such that rendering of the source audio signal by the touch input medium is affected by the touch contact. The location of the touch contact on the touch input medium is determined by analyzing a disturbance by the touch contact on the rendered touch location detection signal. At least a portion of the source audio signal is modified based on an expected effect of the contact on the touch input medium determined using the indication of the detector.

A source audio signal to be rendered by a touch input medium is received. A transmitted signal to be propagated through the touch input medium is sent. The transmitted signal includes the source audio signal and a touch location detection signal. An event is indicated, where the touch input medium has been contacted at a location on the touch input medium by a touch contact such that rendering of the source audio signal by the touch input medium is affected by the touch contact. The location of the touch contact on the touch input medium is determined by analyzing a disturbance by the touch contact on the rendered touch location detection signal. At least a portion of the source audio signal is modified based on an expected effect of the contact on the touch input medium determined using the indication of the detector.

A method for preventing a false touch of a screen includes: sending a bandpass ultrasonic signal; receiving a reflected ultrasonic signal; calculating frequency domain information of the reflected ultrasonic signal; calculating at least one ultrasonic feature vector according to the frequency domain information, the ultrasonic feature vector being used to characterize movement state information of the mobile terminal approaching or moving away from an obstacle; constructing a feature vector set comprising the at least one ultrasonic feature vector; determining whether a condition for preventing a false touch is met according to the feature vector set; disabling a touch function of the touch screen in a case where the condition for preventing the false touch is met.

Acoustic touch sensitive testing techniques are described. In one or more implementations, a touch-sensitive surface of a touch-sensitive device is tested by detecting contact made with the touch sensitive surface using an acoustic sensor and comparing data describing the contact that is received from the acoustic sensor with data describing the contact that is received from the touch-sensitive device.

A touch sensitive device including a panel capable of supporting bending waves, a user-accessible touch sensitive screen on or forming part of a face of the panel, the touch sensitive screen having a plurality of different sensing areas, a plurality of vibration exciters coupled to the panel to apply bending waves to the panel to provide tactile feedback at the plurality of sensing areas in response to the user touching a sensing area, and signal processing means arranged to apply signals to the vibration exciters so as to steer bending waves applied to the panel by the plurality of vibration exciters whereby the amplitude of the applied bending waves is maximized at the sensing area touched by the user and reduced or minimized at each other sensing area.

A touch screen apparatus based on an ultrasonic wave is provided. The touch screen apparatus includes a display, ultrasonic sensors, and a processor. The ultrasonic sensors irradiate ultrasonic signals. The processor, in response to the ultrasonic signals being irradiated from the ultrasonic sensors, reflected from an object touched on the display, and received by the ultrasonic sensors, determines a touch point of the object based on Time of Flights (ToFs) of the received ultrasonic signals.

A touch screen apparatus based on an ultrasonic wave is provided. The touch screen apparatus includes a display, ultrasonic sensors, and a processor. The ultrasonic sensors irradiate ultrasonic signals. The processor, in response to the ultrasonic signals being irradiated from the ultrasonic sensors, reflected from an object touched on the display, and received by the ultrasonic sensors, determines a touch point of the object based on Time of Flights (ToFs) of the received ultrasonic signals.

Example implementations relate to determining a location using time difference of arrival (TDOA). For example, a computing device may include a first sensor to receive a signal at a first time, where the signal is generated by a user contact at a particular location on a keyboard associated with the computing device. The computing device also includes a second sensor to receive the signal at a second time and a third sensor to receive the signal at a third time. The computing device may also include a processor. The processor may calculate a set of TDOAs associated with the first time, the second time, and the third time. The processor may determine the particular location of the user contact using a triangulation based on the set of TDOAs and may identify a character on the keyboard, where the character is associated with the particular location.