摘要:
A blood constituent monitoring method for inducing an active pulse in the blood volume of a patient. The induction of an active pulse results in a cyclic, and periodic change in the flow of blood through a fleshy medium under test. By actively inducing a change of the blood volume, modulation of the volume of blood can be obtained to provide a greater signal to noise ratio. This allows for the detection of constituents in blood at concentration levels below those previously detectable in a non-invasive system. Radiation which passes through the fleshy medium is detected by a detector which generates a signal indicative of the intensity of the detected radiation. Signal processing is performed on the electrical signal to isolate those optical characteristics of the electrical signal due to the optical characteristics of the blood.
摘要:
Small Molecule Metabolite Reporters (SMMRs) for use as in vivo glucose biosensors, sensor compositions, and methods of use, are described. The SMMRs include boronic acid-containing xanthene, coumarin, carbostyril and phenalene-based small molecules which are used for monitoring glucose in vivo, advantageously on the skin.
摘要:
A method and an apparatus for separating a composite signal into a plurality of signals is described. A signal processor receives a composite signal and separates a composite signal in to separate output signals. Feedback from one or more of the output signals is provided to a configuration module that configures the signal processor to improve a quality of the output signals. In one embodiment, the signal processor separates the composite signal by applying a first demodulation scheme to the composite signal to generate a first output signal. In one embodiment, the signal processor also applies a second demodulation scheme to the composite signal to generate a second output signal. In one embodiment, the composite signal is obtained from a detector in a system for measuring one or more blood constituents.
摘要:
An embodiment of the present disclosure provides a noninvasive optical sensor or probe including disposable and reusable components. The assembly of the disposable and reusable components is straightforward, along with the disassembly thereof. During application to a measurement site, the assembled sensor is advantageously secured together while the componentry is advantageously properly positioned.
摘要:
A physiological measurement system has a sensor, a processor, a communications link and information elements. The sensor is configured to transmit light having a plurality of wavelengths into a tissue site and to generate a sensor signal responsive to the transmitted light after tissue attenuation. The processor is configured to operate on the sensor signal so as to derive at least one physiological parameter. The communications link is adapted to provide communications between the sensor and the processor. The information elements are distributed across at least one of the sensor, the processor and the communications link and provide operational information corresponding to at least one of the sensor, the processor and the communications link.
摘要:
A physiological sensor is adapted to removably attach an emitter assembly and a detector assembly to a fingertip. The emitter assembly is adapted to transmit optical radiation having multiple wavelengths into fingertip tissue. The detector assembly is adapted to receive the optical radiation after attenuation by the fingertip tissue. The sensor has a first shell and a second shell hinged to the first shell. A spring is disposed between the shells and urges the shells together. An emitter pad is fixedly attached to the first shell and configured to retain the emitter assembly. A detector pad is fixedly attached to the second shell and configured to retain the detector assembly. A detector aperture is defined within the detector pad and adapted to pass optical radiation to the detector assembly. A contour is defined along the detector pad and generally shaped to conform to a fingertip positioned over the detector aperture.
摘要:
The present disclosure relates to an emitter that is suitable for a noninvasive blood constituent sensor. The emitter is configured as a point optical source that comprises a plurality of LEDs that emit a sequence of pulses of optical radiation across a spectrum of wavelengths. In some embodiments, the plurality of sets of optical sources may each comprise at least one top-emitting LED and at least one super luminescent LED. In some embodiments, the emitter comprises optical sources that transmit optical radiation in the infrared or near-infrared wavelengths suitable for detecting glucose. In order to achieve the desired SNR for detecting analytes like glucose, the emitter may be driven using a progression from low power to higher power. In addition, the emitter may have its duty cycle modified to achieve a desired SNR.
摘要:
The present disclosure relates to an interface for a noninvasive glucose sensor that comprises a front-end adapted to receive an input signals from optical detectors and provide corresponding digital signals. In one embodiment, the front-end comprises switched capacitor circuits that are capable of handling multiple streams signals from the optical detectors. In another embodiment, the front-end comprises transimpedance amplifiers that are capable of handling multiple streams of input signals. In this embodiment, the transimpedance amplifier may be configured based on its own characteristics, such as its impedance, the impedance of the photodiodes to which it is coupled, and the number of photodiodes to which it is coupled.
摘要:
A physiological sensor is adapted to removably attach an emitter assembly and a detector assembly to a fingertip. The emitter assembly is adapted to transmit optical radiation having multiple wavelengths into fingertip tissue. The detector assembly is adapted to receive the optical radiation after attenuation by the fingertip tissue. The sensor has a first shell and a second shell hinged to the first shell. A spring is disposed between the shells and urges the shells together.