Abstract: An electronic device may include a dielectric cover layer defining a finger sensing surface and at least one optical image sensor below the dielectric cover layer. The electronic device may also include at least one optical element associated with the at least one optical image sensor. Light sources may be below the dielectric layer and may be selectively operable in subsets of light sources. A controller may be configured to sequentially operate respective adjacent subsets of light sources while acquiring biometric image data from the at least one optical image sensor.

Abstract: An input device can be integrated within an electronic device and/or operably connected to an electronic device through a wired or wireless connection. The input device can include one or more force sensors positioned below a cover element of the input device or an input surface of the electronic device. The input device can include other components and/or functionality, such as a biometric sensor and/or a switch element.

Abstract: An electronic device may include an optical image sensor that includes optical image sensing circuitry and metallization layers above the optical image sensing circuitry. Each layer may have at least one light transmissive collimation opening therein aligned with the optical image sensing circuitry. The electronic device may also include a light source layer above the optical image sensor and a transparent cover layer above the light source layer defining a finger placement surface configured to receive a finger adjacent thereto.

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: 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: The present disclosure relates to one or more intermediate layers located on a surface of a cover material of an acoustic touch screen. In some examples, the one or more layers can include one or more intermediate layers. The one or more intermediate layers can include a first layer including a plurality of features and a second layer located between the first layer and the cover material. In a touch condition, the touch object can apply a force to the top surface of the acoustic touch sensor. The applied force can create one or more local bends causing the plurality of features to move closer to the cover material and causing one or more surface discontinuities in the cover material. The acoustic waves can undergo reflections (e.g., causing the signal to be attenuated) due to the discontinuities located in the path of the wave propagation.

Abstract: Improving fingerprint image measurement despite damage to the stratum corneum. Determining whether a fingerprint image is adequate for matching with a database. If not, re-measure those image portions that are inadequate (overexposed or underexposed), such re-measuring a minimal selection of image portions. An amount of time or power to re-measure is minimized. Improving fingerprint image data collection despite fixed pattern noise like saturated bars in blocks of picture elements. Determining a histogram of grayscale values, removing fixed pattern noise, and expanding real histogram values to obtain more bits of precision.

Abstract: An acoustic fingerprint imaging system having a plurality of acoustic elements, each acoustic element including a transducer, and independent drive and sense circuitry is disclosed. Drive circuitry may require higher voltage than low voltage sense circuitry. Many embodiments described herein include a ground shifting controller to apply a voltage bias to the low voltage sense circuitry during a drive operation, in order to prevent electrical damage to the sense circuitry.

Abstract: A finger biometric sensing device may include drive circuitry for generating a drive signal and an array of finger biometric sensing pixel electrodes cooperating with the drive circuitry and generating a detected signal based upon placement of a finger adjacent the array. The detected signal may include a drive signal component and a sense signal component superimposed thereon. A gain stage may be coupled to the array and drive signal nulling circuitry may be coupled to the gain stage for reducing the drive signal component from the detected signal. The drive signal nulling circuitry may include a first digital-to-analog converter (DAC) generating an inverted scaled replica of the drive signal for the gain stage. Error compensation circuitry includes a memory storing error compensation data and a second DAC coupled in series with the first DAC compensating an error in the inverted scaled replica based upon the error compensation data.

Abstract: An input device can be integrated within an electronic device and/or operably connected to an electronic device through a wired or wireless connection. The input device can include one or more force sensors positioned below a cover element of the input device or an input surface of the electronic device. The input device can include other components and/or functionality, such as a biometric sensor and/or a switch element.

Abstract: A fingerprint sensor is incorporated in a display stack in an electronic device. A single fingerprint can be captured at one time at a single pre-defined fixed location on a display. Alternatively, a single fingerprint can be acquired at one time at any location on a display. Alternatively, multiple touches on the display can be acquired substantially simultaneously where only one fingerprint is captured at a time or where all of the fingerprints are acquired at the same time. The fingerprint sensor can be implemented as an integrated circuit connected to a bottom surface of a cover sheet, near the bottom surface of the cover sheet, or connected to a top surface of a display. Alternatively, the fingerprint sensor can be implemented as a full panel fingerprint sensor.

Abstract: An electronic device that includes an enclosure having an external surface and a first array of ultrasonic transducers arranged along a first direction and a second array of ultrasonic transducers arranged along a second direction. The first array of ultrasonic transducers may be configured to produce a surface wave along the external surface. A set of scattered waves may be created by the touch on the external surface. The second array of ultrasonic transducers may be configured to receive a portion of the set of scattered waves and produce an output. The device may also include a processing unit that is configured to identify the touch using the output. The processing unit may be further configured to create a reconstruction of at least a portion of a fingerprint associated with the touch on the cover, and to identify the fingerprint using the reconstruction.

Abstract: A capacitive fingerprint sensor includes an array of capacitive sensing elements, readout circuitry electrically coupled to the array of capacitive sensing elements, a block first digital to analog converter (DAC), at least one second DAC, and at least one summing junction electrically coupled to the readout circuitry, the first DAC, and the at least one second DAC. The readout circuitry is adapted to read out pixel voltages from a group of each block of capacitive sensing elements. The first DAC is adapted to provide a block baseline voltage for each block of capacitive sensing elements. The second DAC is adapted to provide a pixel baseline voltage difference for one capacitive sensing element of each group of each block. The summing junction is adapted to subtract the received block baseline voltage and the received pixel baseline voltage difference from the corresponding pixel voltage of each row of each block.

Abstract: An authentication device may include a housing and a finger sensor carried by the housing and including first processing circuitry and a finger sensing area coupled thereto. The first processing circuitry may be configured to generate finger image data based upon a finger positioned adjacent the finger sensing area, and generate and store a first template based upon the finger image data. The authentication device may include second processing circuitry carried by the housing and configured to obtain the finger image data from the first processing circuitry. The second processing circuitry may be configured to generate a second template based upon the finger image data. The first processing circuitry may further be configured to obtain the second template from second processing circuitry, and validate the second template against the first template.

Abstract: Thermal compensation can be applied to force measurements of a force-sensitive button. A temperature differential between an object and the force-sensitive button can result in changes in the reconstructed force by the force sensor due to thermal effects rather than actual user force, which in turn can result in degraded performance of the force sensor (e.g., false positive or inconsistent activation force). In some examples, a force-sensitive button can include a force sensor configured to measure an amount of force applied to the force-sensitive button, and a temperature sensor configured to measure a temperature associated with the force sensor. The measured temperature can be used to compensate the amount of force measured by the force sensor based on the temperature associated with the force sensor. In some examples, the thermal compensation can be applied when an object is detected contacting the force-sensitive button (i.e., when rapid temperature differentials can occur).

Abstract: An electronic device may include a housing, a display carried by the housing and switchable between a power saving mode and an operating power mode, and a finger biometric sensor carried by the housing and configured to sense an image of an object adjacent thereto. The electronic device may also include a device cover carried by the housing and configured to be movable between an open position exposing the finger biometric sensor and a closed position covering the finger biometric sensor. The device cover may include a cover panel and an electrically conductive member carried by the cover panel adjacent the finger biometric sensor when in the closed position. A controller may be coupled to the finger biometric sensor and configured to determine when the electrically conductive member is adjacent the finger biometric sensor, and selectively switch the display between the power saving mode and the operating power mode based thereon.

Abstract: A finger biometric sensing device may include drive circuitry for generating a drive signal and an array of finger biometric sensing pixel electrodes cooperating with the drive circuitry and generating a detected signal based upon placement of a finger adjacent the array. The detected signal may include a drive signal component and a sense signal component superimposed thereon. A gain stage may be coupled to the array and drive signal nulling circuitry may be coupled to the gain stage for reducing the drive signal component from the detected signal. The drive signal nulling circuitry may include a first digital-to-analog converter (DAC) generating an inverted scaled replica of the drive signal for the gain stage. Error compensation circuitry includes a memory storing error compensation data and a second DAC coupled in series with the first DAC compensating an error in the inverted scaled replica based upon the error compensation data.

Abstract: An electronic device may include an optical image sensor and a pin hole array mask layer above the optical image sensor. The electronic device may also include a display layer above the pin hole array mask layer that includes spaced apart display pixels, and a transparent cover layer above the display layer defining a finger placement surface capable of receiving a finger adjacent thereto.

Abstract: Acoustic touch detection (touch sensing) system architectures and methods can be used to detect an object touching a surface. Position of an object touching a surface can be determined using time-of-flight (TOF) bounding box techniques, or acoustic image reconstruction techniques, for example. Acoustic touch sensing can utilize transducers, such as piezoelectric transducers, to transmit ultrasonic waves along a surface and/or through the thickness of an electronic device. Location of the object can be determined, for example, based on the amount of time elapsing between the transmission of the wave and the detection of the reflected wave. An object in contact with the surface can interact with the transmitted wave causing attenuation, redirection and/or reflection of at least a portion of the transmitted wave. Portions of the transmitted wave energy after interaction with the object can be measured to determine the touch location of the object on the surface of the device.

Abstract: An electronic device may include a finger biometric sensor that includes an array of electric field sensing pixels and image data output circuitry coupled thereto and capable of processing the image data from each of sub-arrays of the array of electric field sensing pixels. The electronic device may also include a dielectric layer over the array of electric field sensing pixels and causing electric field diffusion so that the image data output circuitry generates image data corresponding to a blurred finger image. The electronic device also includes deblurring circuitry coupled to the image data output circuitry and capable of processing the image data from each of the plurality of sub-arrays of the array of electric field sensing pixels to produce processed image data representative of a deblurred finger image.