Abstract: A system for concentrating particles in an air stream includes an air channel having a first open end and a second open end. The air channel may be enclosed by a channel wall extending from at least the first open to the second open end. Two or more heater elements may be positioned between the first open end and the second open end. The heater elements may be positioned near a periphery of the air channel and cooperatively configured to force particles in the air stream away from the periphery and towards an interior region of the air channel. Particles in the air stream may be thermophoretically forced towards the interior region of the air channel when the heater elements are heated and thermal gradients emanating from the heater elements are generated.

Abstract: A system for analyzing particles in an air stream includes a first heater element configured to deflect particles in an interior region of the air stream towards a peripheral wall of an air channel encompassing the air stream, a second heater element controllable to deflect the particles in a first lateral direction along the peripheral wall, and a third heater element controllable to deflect the particles in a second lateral direction along the peripheral wall. Thermal gradients in the air channel generated by the heater elements may thermophoretically force particles towards the peripheral wall in a direction perpendicular to the air stream to allow thermophoretic forcing and scanning of particles in either the first lateral direction or the second lateral direction along the peripheral wall and onto a surface of a particle detector. Systems and methods for scanning particles with thermophoretic forces are disclosed.

Abstract: A method for analyzing particles in an air stream includes concentrating the particles in an interior region of the air stream and deflecting the concentrated particles in the air stream with a generated thermal gradient. Smaller particles in the air stream may be selectively deflected away from the interior region and towards a periphery of the air stream at a different rate than larger particles in the air stream. The generated thermal gradient may be controlled to deflect particles in a selected particle size range onto a surface of a particle detector. An effective mass of the collected particles and an aerosol mass concentration estimate of the particles within the selected particle size range may be generated. Systems for analyzing particles are also disclosed.

Abstract: Techniques describe structures and methods for generating larger output signals and improving image quality of ultrasonic sensors by inclusion of an acoustic cavity in the sensor stack. In some embodiments, an ultrasonic sensor unit may be tuned during manufacturing or during a provisioning phase to work with different thicknesses and materials. In some embodiments, a standing wave signal may be generated using an acoustic cavity in the ultrasonic sensor unit for capturing an ultrasonic image of an object placed on a sensor surface. In some implementations, the ultrasonic sensor may include an ultrasonic transmitter, a piezoelectric receiver, a thin film transistor (TFT) layer and a TFT substrate positioned between the transmitter and the receiver, one or more adhesive layers, and optional cover materials and coatings. The thickness, density and speed of sound of the sensor materials and associated adhesive attachment layers may be used to attain the desired acoustic cavity and improved performance.

Abstract: A biometric system may include an ultrasonic sensor array, a light source system and a control system. Some implementations may include an ultrasonic transmitter. The control system may be capable of controlling the light source system to emit light and of receiving signals from the ultrasonic sensor array corresponding to acoustic waves emitted from portions of a target object in response to being illuminated with the light emitted by the light source system. The control system may be capable of performing a user authentication process that is based, at least in part, on the signals from the ultrasonic sensor array.

Abstract: Systems, methods and apparatus for configuring a fingerprint sensor to operate in a capacitive sensing mode and an ultrasonic sensing mode are disclosed. A fingerprint sensor may be configured to operate in a capacitive sensing mode by driving a sensing electrode using a controller. In some implementations, an object positioned on or near the sensing electrode may be detected using the fingerprint sensor in the capacitive sensing mode, and the controller can drive electrodes of the fingerprint sensor differently to configure the fingerprint sensor to operate in an ultrasonic sensing mode. In some implementations, an applications processor may be instructed to authenticate a fingerprint of the object from image data obtained when the fingerprint sensor is operating in the ultrasonic sensing mode. In some implementations, a display of a mobile device containing the fingerprint sensor may be unlocked, or the mobile device may be woken up when the fingerprint is authenticated.

Abstract: An apparatus may include an array of piezoelectric micromachined ultrasonic transducers (PMUTs) and a control system configured to communicate with the array of PMUTs. The control system may be configured to determine a target location within a human body and to control the array of PMUTs to focus ultrasonic waves at the target location.

Abstract: Systems, methods and apparatus for configuring a fingerprint sensor to operate in a capacitive sensing mode and an ultrasonic sensing mode are disclosed. A fingerprint sensor may be configured to operate in a capacitive sensing mode by driving a sensing electrode using a controller. In some implementations, an object positioned on or near the sensing electrode may be detected using the fingerprint sensor in the capacitive sensing mode, and the controller can drive electrodes of the fingerprint sensor differently to configure the fingerprint sensor to operate in an ultrasonic sensing mode. In some implementations, an applications processor may be instructed to authenticate a fingerprint of the object from image data obtained when the fingerprint sensor is operating in the ultrasonic sensing mode. In some implementations, a display of a mobile device containing the fingerprint sensor may be unlocked, or the mobile device may be woken up when the fingerprint is authenticated.

Abstract: An apparatus may include an ultrasonic sensor array and a control system. The control system may be configured to acquire first image data generated by the ultrasonic sensor array corresponding to at least one first reflected ultrasonic wave received by at least a portion of the ultrasonic sensor array from a target object during a first acquisition time window. The control system may be configured to acquire second image data generated by the ultrasonic sensor array corresponding to at least one second reflected ultrasonic wave received by at least a portion of the ultrasonic sensor array from the target object during a second acquisition time window that is longer than the first acquisition time window. The control system may further be configured to initiate an authentication process based on the first image data and the second image data.

Abstract: This disclosure provides systems, methods and apparatus, including computer programs encoded on computer storage media, for making and using accelerometers. Some such accelerometers include a substrate, a first plurality of electrodes, a second plurality of electrodes, a first anchor attached to the substrate, a frame and a proof mass. The substrate may extend substantially in a first plane. The proof mass may be attached to the frame, may extend substantially in a second plane and may be substantially constrained for motion along first and second axes. The frame may be attached to the first anchor, may extend substantially in a second plane and may be substantially constrained for motion along the second axis. A lateral movement of the proof mass in response to an applied lateral acceleration along the first or second axes may result in a change in capacitance at the first or second plurality of electrodes.

Abstract: The present invention describes ophthalmic lipoic acid choline ester compositions and specific processes to produce biocompatible formulations of said compositions suitable for the eye.

Abstract: Disclosed are methods, devices, apparatuses, and systems for an under-display ultrasonic fingerprint sensor. A display device may include a platen, a display underlying the platen, and an ultrasonic fingerprint sensor underlying the display, where the ultrasonic fingerprint sensor is configured to transmit and receive ultrasonic waves via an acoustic path through the platen and the display. A light-blocking layer and/or an electrical shielding layer may be provided between the ultrasonic fingerprint sensor and the display, where the light-blocking layer and/or the electrical shielding layer are in the acoustic path. A mechanical stress isolation layer may be provided between the ultrasonic fingerprint sensor and the display, where the mechanical stress isolation layer is in the acoustic path.

Abstract: Implementations of the subject matter described herein relate to sensors including piezoelectric micromechanical ultrasonic transducer (PMUT) sensor elements and arrays thereof. The PMUT sensor elements may be switchable between a non- ultrasonic force detection mode and an ultrasonic imaging mode. A PMUT sensor element may include a diaphragm that is capable of a static displacement on application of a force and is capable of a dynamic displacement when the PMUT sensor element transmits or receives ultrasonic signals. In some implementations, a PMUT sensor element includes a two dimensional-electron gas structure on the diaphragm. The sensors may further include a sensor controller configured to switch between a non-ultrasonic force detection mode and an ultrasonic imaging mode for one or more of the PMUT sensor elements, wherein an applied force is measured in the non-ultrasonic force detection mode and wherein an object is imaged ultrasonically during the ultrasonic imaging mode.

Abstract: Techniques for associating environmental information with fingerprint images for fingerprint enrollment and matching are presented. The techniques may include capturing, using a fingerprint sensor of a mobile device, one or more images of a fingerprint. The techniques may include analyzing the one or more images to obtain fingerprint information associated with the fingerprint. The techniques may include obtaining, via an orientation sensor of the mobile device, environmental information indicating an orientation of the mobile device associated with the capturing of the one or more images. The techniques may additionally include generating, using the fingerprint information, an enrollment template for the fingerprint. The techniques may include associating the enrollment template with the environmental information.

Abstract: An apparatus may include an ultrasonic sensor array and a control system. The control system may be configured to acquire first image data generated by the ultrasonic sensor array corresponding to at least one first reflected ultrasonic wave received by at least a portion of the ultrasonic sensor array from a target object during a first acquisition time window. The control system may be configured to acquire second image data generated by the ultrasonic sensor array corresponding to at least one second reflected ultrasonic wave received by at least a portion of the ultrasonic sensor array from the target object during a second acquisition time window that is longer than the first acquisition time window. The control system may further be configured to initiate an authentication process based on the first image data and the second image data.

Abstract: A mobile device may include a first fingerprint sensor, including a platen, residing on a first side of the mobile device, and a display residing on a second side of the mobile device. The second side may be opposite from the first side. The mobile device may include a control system configured for communication with the first fingerprint sensor and the display. The control system may be further configured for receiving first fingerprint sensor signals from the first fingerprint sensor corresponding to a fingerprint contact area of a first finger positioned on the platen, for detecting one or more finger distortions corresponding to changes of the first fingerprint sensor signals and for controlling the mobile device based, at least in part, on the one or more finger distortions.

Abstract: An apparatus may include an ultrasonic sensor system, a platen, a set of bioimpedance electrodes proximate the platen and a control system configured for communication with the ultrasonic sensor system and the set of bioimpedance electrodes. The control system may be further configured for controlling the ultrasonic sensor system to transmit ultrasonic waves, receiving ultrasonic sensor signals from the ultrasonic sensor system corresponding to ultrasonic waves reflected from a portion of a body in contact with the platen, receiving bioimpedance measurements from the set of bioimpedance electrodes and estimating a status of one or more biometric indicators of the portion of the body based on the ultrasonic sensor signals and the bioimpedance measurements.

Abstract: Some disclosed methods involve controlling an ultrasonic sensor system to transmit ultrasonic waves and receiving signals from the ultrasonic sensor system corresponding to ultrasonic waves reflected from a finger positioned on a platen. The methods may involve obtaining fingerprint image data corresponding to the signals and determining a change in a force of at least a portion of the finger on the platen corresponding to the signals.

Abstract: Methods, systems and storage media are described, each of which may be used to generate an image of an object using ultrasonic plane waves. For example, the generated image may be of a target object positioned on a platen surface. The image may be derived from corrected output signals obtained from a plurality of selected sensor pixels. The corrected output signals may adjust for diffraction of reflected ultrasonic plane waves from a target object positioned on the platen surface. The target object may be a finger or a tip of a stylus.

Abstract: This disclosure provides systems, methods and apparatus related to an ultrasonic sensor for detecting ultrasonic energy. In some implementations, the ultrasonic sensor includes a piezoelectric receiver layer bonded with an adhesive to an array of pixel circuits disposed on a substrate, each pixel circuit in the array including at least one thin film transistor (TFT) element and having a pixel input electrode electrically coupled to the pixel circuit. Methods of forming ultrasonic sensors include bonding piezoelectric receiver layers to TFT arrays.