Patent ID: 6647279
Filing Date: 2003-11-11
Classification: A61B

Abstract:
A photoplethysmographic measurement apparatus for measuring one or more blood analyte levels or one or more hemodynamic parameters in a tissue-under-test, comprising:a plurality of separate emitters, wherein each emitter produces a light signal having a unique spectral content, said emitters separated into two sets of at least one emitter each; a sensor which makes direct contact with the tissue-under-test and provides an output aperture through which light signals are delivered to the tissue-under-test; housing means for housing each of the two sets of emitters in two separate locations, said housing means comprising a first housing means located proximal to said sensor and a second housing means located some distance from said first housing means; means for transporting said light signals from said first and said second housing means to said sensor; means for guiding the light signals from said first and second housing means through said output aperture to be incident on the tissue-under-test; means for receiving a portion of the light signal exiting the tissue-under-test and converting said received light-signal to an electronic signal indicative of the said received light signal; means for processing said received light signal to determine one or more blood analyte levels or one or more hemodynamic parameters.