Abstract: A wireless power transmission system has a wireless power receiving device with a wireless power receiving coil that is located on a charging surface of a wireless power transmitting device with a wireless power transmitting coil array. Control circuitry in the wireless power transmitting device may use inverter circuitry to supply alternating-current signals to coils in the coil array, thereby transmitting wireless power signals. The control circuitry may also be used to detect foreign objects on the coil array such as metallic objects without wireless power receiving coils. For example, control circuitry may use inductance measurements from the coils in the coil array to determine a probability value indicative of whether a foreign object is present on the charging surface. The control circuitry may compare the probability value to a threshold and take suitable action in response to the comparison.

Abstract: A wireless power transmission system has a wireless power receiving device with a wireless power receiving coil that is located on a charging surface of a wireless power transmitting device with a wireless power transmitting coil array. Control circuitry in the wireless power transmitting device may use inverter circuitry to supply alternating-current signals to coils in the coil array, thereby transmitting wireless power signals. The control circuitry may also be used to detect foreign objects on the coil array such as metallic objects without wireless power receiving coils. For example, control circuitry may use inductance measurements from the coils in the coil array to identify segments of the coil array that correspond to potential wireless power receiving devices. The control circuitry may control wireless power transmission based on a comparison between the number of identified segments corresponding to potential wireless power receiving devices and a number of received device-identifiers.

Abstract: Embodiments of the present disclosure provide a method and system for dynamically controlling a current that is applied to a light source of an optical encoder.

Abstract: Disclosed herein are methods and systems for compensating for drift that may be present in a force sensing device. In some embodiments, the force sensing device may be calibrated to compensate for the drift. The calibration may include receiving an input waveform associated with a received amount of force on the force sensing device. A system model that approximates a transfer function that provides an output waveform associated with the input waveform is then determined. Using the system model, an inverse transfer function associated with the system model is also determined. The inverse transfer function may then be applied to the output waveform which compensates for the drift.

Abstract: Rotary encoders suitable for inclusion within small form factor devices (e.g., as input devices to small form factor electronic devices) are disclosed. In one aspect, a light source can illuminate a pattern on a rotatable shaft in order to reflect the pattern onto an array of optical sensors. Each optical sensor from the array of optical sensors can be polled at the same time to yield a snapshot vector. The snapshot vector can be projected onto a subspace spanned by two vectors selected in part on the pattern of the rotatable shaft and the distance separating the shaft and array. The resulting projection can be used to determine error and phase of the reflected pattern across the array of optical sensors. The phase of the reflected pattern can correlate to rotation of the shaft.

Abstract: A light source in a rotary optical encoder can illuminate a pattern on a rotatable shaft and an optical sensor can detect either the light that is reflected or transmitted based on the pattern. A sampling rate of the optical sensor is dynamically adjusted based on a rotational speed of the rotatable shaft. A pulse rate of the light source may also be dynamically adjusted based on the sampling rate of the optical sensor.

Abstract: A light source in a rotary optical encoder can illuminate a pattern on a rotatable shaft and an optical sensor can detect either the light that is reflected or transmitted based on the pattern. A sampling rate of the optical sensor is dynamically adjusted based on a rotational speed of the rotatable shaft. A pulse rate of the light source may also be dynamically adjusted based on the sampling rate of the optical sensor.

Abstract: Disclosed herein is an electronic device having a proximity sensor for determining whether an object, such as a user's finger, is in proximity to or in contact with an input mechanism of the electronic device.

Abstract: Systems and methods for detecting user input to an electronic device are disclosed. The electronic device can include an input sensor system that itself includes an input-sensitive structure that compresses or expands in response to user input. The input sensor system measures and electrical property of the input-sensitive structure for changes. The input sensor system is coupled to an accelerometer to receive acceleration data to modify the detected changes to the input-sensitive structure.

Abstract: Disclosed herein are methods and systems for compensating for drift that may be present in a force sensing device. In some embodiments, the force sensing device may be calibrated to compensate for the drift. The calibration may include receiving an input waveform associated with a received amount of force on the force sensing device. A system model that approximates a transfer function that provides an output waveform associated with the input waveform is then determined. Using the system model, an inverse transfer function associated with the system model is also determined. The inverse transfer function may then be applied to the output waveform which compensates for the drift.

Abstract: Embodiments of the present disclosure provide a method and system for dynamically controlling a current that is applied to a light source of an optical encoder.