Abstract: Precomputed databases of sensor responses are used to convert measurement data into properties of interest, for example, conductivity or lift-off. These databases of responses may be generated prior to data acquisition and provide sensor response values that span appropriate ranges for the property values. After data acquisition, estimates for the property values are obtained from measurement values by minimizing the difference between the database of responses and the measurement values. The minimization can take the form of a least-squares minimization. Alternatively, iterative techniques can be used to minimize the difference between the database and measurement values.

Abstract: A finger position sensing apparatus, typically used in a fingerprint sensing system, includes a position pickup plate disposed generally orthogonally with respect to an expected direction of movement of a finger and a plurality of position drive plates having different spacings from the position pickup plate to define plurality of position sensor gaps between respective position drive plates and the position pickup plate. The position drive plates are dimensioned and spaced from the position pickup plate to sense the bulk of a finger rather than fingerprint features.

Abstract: Image sensing apparatus includes an image pickup plate disposed generally orthogonally with respect to an expected direction of movement of an object, such as a finger, multiple image drive plates in spaced relation to the image pickup plate to define sensor gaps between respective image drive plates and the image pickup plate, and a reference plate disposed substantially parallel to the image pickup plate. The reference plate is spaced from the image pickup plate to permit common mode noise and coupling to be cancelled and is spaced from the image drive plates to permit a differential image signal to develop between the image pickup plate and the reference plate. A differential amplifier coupled to the image pickup plate and the reference plate provides noise cancellation. The apparatus may further include a comb plate spaced from the reference plate and coupled to a reference potential, such as ground.

Abstract: A tire pressure monitoring system is provided that includes a switched capacitor circuit having a clock with two non-overlapping clock phases that control a state of analog switches of the switched capacitor circuit. The system uses tire pressure sensor MEMS capacitors that are measured differentially. A capacitance-to-voltage converter is connected to the MEMS sense capacitor, and a sigma-delta converter having a comparator with a first digital output state and a second digital output state is used. The first output state is a sum of reference voltages and the second output state is a difference of the reference voltages. An average value of the capacitance-to-voltage converter output is driven to a zero value and a digital output is provided of the average output states that is equal to a difference between the MEMS capacitors divided by their sum multiplied by a ratio of the reference voltages.

Abstract: A set of curved components, such as the dovetail region of engine blades, are inspected by mounting each component into a circular carousel in a vertical orientation and rotating the carousel to move each component toward and away from an inspection site. The inspection site clamps a flexible eddy current sensor array to the curved material surface, scans the array over the surface, records the sensor position. A rigid element having a surface geometry similar to the surface shape of the component can be attached to the component to facilitate scanning of the sensor array over a component edge. The response of each sense element in the array may be converted into an effective material property and sense element proximity to the component material surface to verify the quality of the inspection scan and the presence of a defect such as a crack.

Abstract: Methods are described for assessing material condition. These methods include the use of multiple source fields for interrogating and loading of a multicomponent test material. Source fields include electric, magnetic, thermal, and acoustic fields. The loading field preferentially changes the material properties of a component of the test material, which allows the properties of the component materials to be separated. Methods are also described for monitoring changes in material state using separate drive and sense electrodes with some of the electrodes positioned on a hidden or even embedded material surface. Statistical characterization of the material condition is performed with sensor arrays that provide multiple responses for the material condition during loading. The responses can be combined into a statistical population that permits tracking with respect to loading history.

Abstract: A gap-change sensing through capacitive techniques is disclosed. In one embodiment, an apparatus includes a first conductive surface and a second conductive surface substantially parallel to the first conductive surface, and a sensor to generate a measurement based on a change in a distance between the first conductive surface and the second conductive surface. The change in the distance may be caused by a deflection of the first conductive surface with respect to the second conductive surface, and the deflection may be a compressive force and/or an expansive force. The sensor may apply an algorithm that converts a change in capacitance to at least one of a change in voltage and/or a change in frequency to generate the measurement. The change in the distance may be caused by a load applied to the surface above the first conductive surface with respect to the second conductive surface.

Abstract: The invention is directed to a system for securing an integrated circuit chip used in an electronic device by utilizing a circuit or other entity to produce physically unclonable functions (PUF) to generate a security word, such as an RSA public or private key. A PUF, according to its name and configuration, performs functions that are substantially difficult to be duplicated or cloned. This allows the invention to provide a unique and extremely secure system for authentication. In operation, the stored parameters can be used to more efficiently and quickly authenticate the device without the need to run the burdensome security key generation processes without compromising the level of security in the device. Such a system can be used to substantially eliminate the time to produce security keys when a user needs to authenticate the device at power up or other access point.

Abstract: The linear distance measurement apparatus comprises a non-driven, extendable/retractable arm mechanism that is mounted such that an arc movement of the arm describes a linear distance. A rotary sensor mechanism is coupled to the non-driven arm. The sensor measures the arc movement of the arm and translates the arc movement to the linear distance.

Abstract: A fingerprint sensor in accordance with the invention includes a non-conductive substrate providing a first surface onto which a user can apply a fingerprint to be sensed. A sensor circuit is applied to a second surface of the non-conductive substrate opposite the first surface to sense a fingerprint when juxtaposed proximally thereto. An electrostatic discharge conductor is applied to the non-conductive surface and is located between an area where a fingerprint is swiped and the sensor circuit. The electrostatic discharge conductor discharges electrostatic charge resulting from a user swiping a fingerprint across the first surface.

Abstract: Combined wound and micro-fabricated winding constructs are described for the inspection of materials and the detection and characterization of hidden features or flaws. These constructs can be configured as sensors or sensor arrays that are surface mounted or scanned over conducting and/or magnetizable test materials. The well-defined geometry obtained micro-fabricated windings and from carefully wound coils with known winding positions permits the use of model based inversions of sensed responses into material properties. In a preferred embodiment, the primary winding is a wound coil and the sense elements are etched or printed. The drive or sense windings can also be mounted under fasteners to improve sensitivity to hidden flaws. Ferrites and other means may be used to guide the magnetic flux and enhance the magnetic field in the test material.

Abstract: The invention relates to the use of particles comprising binding ligands and electron transfer moieties (ETMs). Upon binding of a target analyte, a particle and a reporter composition are associated and transported to an electrode surface. The ETMs are then detected, allowing the presence or absence of the target analyte to be determined.

Abstract: The invention relates to the use of particles comprising binding ligands and electron transfer moieties (ETMs). Upon binding of a target analyte, a particle and a reporter composition are associated and transported to an electrode surface. The ETMs are then detected, allowing the presence or absence of the target analyte to be determined.

Abstract: The present invention is directed to the detection of target analytes using electronic techniques, particularly AC techniques.

Abstract: Enhanced accuracy finger position and motion sensors devices, algorithms, and methods are disclosed that can be used in a variety of different applications. The sensors can be used in conjunction with partial fingerprint imagers to produce improved fingerprint scanners. The finger motion sensors may also be used (either with or without a partial fingerprint imager) to control electronic devices. When several of these finger motion and position sensors are aligned in different directions, finger motion over a two dimensional surface may be detected. This creates a finger controlled “mouse” computer input device. Motion of a finger along the surface of such sensors may allow a user to control the movement of an indicator on a display screen, and control a microprocessor device. Such techniques are particularly useful for small space constrained devices, such as cell phones, smart cards, music players, portable computers, personal digital accessories, and the like.

Abstract: The invention is directed to devices that allow for simultaneous multiple biochip analysis. In particular, the devices are configured to hold multiple cartridges comprising biochips comprising arrays such as nucleic acid arrays, and allow for high throughput analysis of samples.

Abstract: A sensor which uses a plurality of partial fingerprint readers (imagers), and various computational algorithms, to detect changes in fingerprint images as a function of finger movement. The sensor can provide both finger motion information and fingerprint images. The sensor uses multiple partial fingerprint readers, arranged in different directions on a surface, to detect finger motion in two dimensions. The sensor can also detect the relative speed and direction of finger movement. Some sensor embodiments use deep finger penetrating radio frequency (RF) based circuits, which can be inexpensively printed or formed on the surface of robust and flexible dielectric materials such as Kapton tape. The sensor also has textured surfaces to help guide the user. The sensor both small and robust, and is well suited for control applications for low-cost mass market microprocessor controlled devices such as cell phones, MP3 players, laptop computers, and other devices.

Abstract: Enhanced accuracy finger position and motion sensors devices, algorithms, and methods are disclosed that can be used in a variety of different applications. The sensors can be used in conjunction with partial fingerprint imagers to produce improved fingerprint scanners. The finger motion sensors may also be used (either with or without a partial fingerprint imager) to produce highly accurate fingerprint images as well as to control electronic devices. Here improved signal analysis algorithms and methods are disclosed that enable finger position to be determined with higher levels of accuracy as the finger is swiped over finger position sensing arrays. These algorithms are particularly useful for deep finger penetrating radio frequency (RF) based sensing arrays.

Abstract: Enhanced accuracy finger position and motion sensors devices, algorithms, and methods are disclosed that can be used in a variety of different applications. The sensors can be used in conjunction with partial fingerprint imagers to produce improved fingerprint scanners. Such improved scanners can use image analysis techniques, such as interpolation between partial fingerprint images to correct for missing data, or discarding redundant partial fingerprint image data, to produce adequate fingerprint images even when the finger has not been applied to the sensor using an optimum technique.

Abstract: The invention is directed to devices that allow for simultaneous multiple biochip analysis. In particular, the devices are configured to hold multiple cartridges comprising biochips comprising arrays such as nucleic acid arrays, and allow for high throughput analysis of samples.