Systems and methods for monitoring the condition of electrodes used in biological signal measurement are provided. One method includes applying a first test signal having a first frequency to at least one of a plurality of electrodes and applying a second test signal having a second frequency to at least one of the plurality of electrodes. Both frequencies are below a frequency range associated with the biological signal. The method further includes capturing the biological signal while applying the plurality of test signals and generating an output signal that includes both the measured biological signal and the plurality of test signals. The method further includes retrieving an output amplitude for each of the plurality of test signals from the output signal and calculating an estimated impedance for each of the plurality of electrodes based on the retrieved output amplitudes of the plurality of test signals.

The present disclosure relates to noninvasive methods, devices, and systems for measuring various blood constituents or analytes, such as glucose. In an embodiment, a light source comprises LEDs and super-luminescent LEDs. The light source emits light at at least wavelengths of about 1610 nm, about 1640 nm, and about 1665 nm. In an embodiment, the detector comprises a plurality of photodetectors arranged in a special geometry comprising one of a substantially linear substantially equal spaced geometry, a substantially linear substantially non-equal spaced geometry, and a substantially grid geometry.

One variation of a method for testing contact quality of electrical-biosignal electrodes includes: outputting a drive signal through a driven electrode, the drive signal comprising an alternating-current component oscillating at a reference frequency and a direct-current component; reading a set of sense signals from a set of sense electrodes at a first time; calculating a first combination of the set of sense signals; calculating a first direct-current value comprising a combination of the first combination and the direct-current component of the drive signal at approximately the first time; and at a second time succeeding the first time, shifting the direct-current component of the drive signal output by the driven electrode to the first direct-current value.

A mobile-platform imaging device uses compression of the target region to generate an image of an object. A tactile sensor has an optical waveguide with a flexible, transparent first layer. Light is directed into the waveguide. Light is scattered out of the first layer when the first layer is deformed. The first layer is deformed by the tactile sensor being pressed against the object. A force sensor detects a force pressing the tactile sensor against the object and outputs corresponding force information. A first communication unit receives the force information from the force sensor. A receptacle holds a mobile device with a second communication unit and an imager that can generate image information using light scattered out of the first layer. The first communication unit communicates with the second communication unit and the mobile device communicates with an external network.

The present invention relates generally to a system and method for measuring the structural characteristics of an object. The object is subjected to an energy application processes and provides an objective, quantitative measurement of structural characteristics of an object. The system may include a device, for example, a percussion instrument, capable of being reproducibly placed against the object undergoing such measurement for reproducible positioning. The system does not include an external on/off switch or any remote on/off switching mechanism. The system also includes a disposable feature or assembly for minimizing cross-contamination between tests. The structural characteristics as defined herein may include vibration damping capacities, acoustic damping capacities, structural integrity or structural stability.

An apparatus for estimating bio-information based on pulse wave signals of multiple wavelengths is disclosed. The bio-information estimating apparatus may include: a sensor part comprising a pulse wave sensor configured to measure a multi-wavelength pulse wave signal at a first point in time when a first pressure is applied from an object to the sensor part and at a second point in time when a second pressure is applied from the object to the sensor part; and a processor configured to estimate bio-information based on a difference between the multi-wavelength pulse wave signal measured at the first pressure and the multi-wavelength pulse wave signal measured at the second pressure.

A watch band is disclosed. The watch band maintains a substantially constant tension throughout changes in its length while worn by a user. Such changes in length may occur automatically to accommodate changes in the size and circumference of a user's wrist as they move their wrist normally. By maintaining a constant tension, the watch band also maintains a constant force on the user's wrist, and causes a watch body attached to the watch band to also maintain a constant force on the user's wrist. This can increase a user's comfort, since the watch will not get tighter or constrict their wrist as they straighten and bend their wrist. It can also help optimize operation of any sensors in the watch band or watch body that benefit from being held against the user's wrist with a constant force, such as some physiological sensors.

An apparatus for estimating bio-information includes a pulse wave sensor configured to measure a pulse wave signal from an object, for a predetermined period of time, a processor configured to extract DC components of the pulse wave signal measured for the predetermined period of time, normalize the extracted DC components, based on at least one of the extracted DC components of the pulse wave signal measured at a time when a reference force is applied by the object to the pulse wave sensor, and estimate the bio-information, based on the normalized DC components.

A vital signs monitoring system, the system including: (a) an ear device including: a curved body adapted to a shape of an ear, an upper end, a lower end, two opposite facing sides, a first side adapted to be proximal a skull and a second side adapted to be proximal an earlobe, the ear device including: (i) a temperature sensor adapted to sense a body temperature from a depression between a lower, jawbone and skull; and (b) a control system, including a processor and a memory, configured and operable to control operation of the ear device, to collect signals received from at least one sensor including the temperature sensor, to process the signals to provide medically significant results.

The invention disclosed herein relates to improvements in the collection personal health data. It further relates to a Personal Health Monitor (PHM), which may be a Personal Hand Held Monitor (PHHM), that incorporates a Signal Acquisition Device (SAD) and a processor with its attendant screen and other peripherals. The SAD is adapted to acquire signals which can be used to derive one or more measurements of parameters related to the health of a user. The computing and other facilities of the PHM with which the SAD is integrated are adapted to control and analyse signals received from the SAD. The personal health data collected by the SAD may include data related to one or more of blood pressure, pulse rate, blood oxygen level (SpO.sub.2), body temperature, respiration rate, ECG, cardiac output, heart function timing, arterial stiffness, tissue stiffness, hydration, blood viscosity, blood pressure variability, the concentration of constituents of the blood such as glucose or alcohol and the identity of the user.