Abstract: An apparatus and method for noninvasive determination of analyte properties of human tissue by quantitative infrared spectroscopy to clinically relevant levels of precision and accuracy. The system includes subsystems optimized to contend with the complexities of the tissue spectrum, high signal-to-noise ratio and photometric accuracy requirements, tissue sampling errors, calibration maintenance problems, and calibration transfer problems. The subsystems can include an illumination/modulation subsystem, a tissue sampling subsystem, a data acquisition subsystem, a computing subsystem, and a calibration subsystem. The invention can provide analyte property determination and identity determination or verification from the same spectroscopic information, making unauthorized use or misleading results less likely than in systems that use separate analyte and identity determinations. The invention can be used to control and monitor individuals accessing controlled environments.

Abstract: Methods and apparatuses for the determination of an attribute of the tissue of an individual use non-invasive Raman spectroscopy. For example, the alcohol concentration in the blood or tissue of an individual can be determined non-invasively. A portion of the tissue is illuminated with light, the light propagates into the tissue where it is Raman scattered within the tissue. The Raman scattered light is then detected and can be combined with a model relating Raman spectra to alcohol concentration in order to determine the alcohol concentration in the blood or tissue of the individual. Correction techniques can be used to reduce determination errors due to detection of light other than that from Raman scattering from the alcohol in the tissue.

Abstract: Methods and apparatuses for the determination of an attribute of the tissue of an individual use non-invasive Raman spectroscopy. For example, the alcohol concentration in the blood or tissue of an individual can be determined non-invasively. A portion of the tissue is illuminated with light, the light propagates into the tissue where it is Raman scattered within the tissue. The Raman scattered light is then detected and can be combined with a model relating Raman spectra to alcohol concentration in order to determine the alcohol concentration in the blood or tissue of the individual. Correction techniques can be used to reduce determination errors due to detection of light other than that from Raman scattering from the alcohol in the tissue.

Abstract: An apparatus and method for noninvasive determination of analyte properties of human tissue by quantitative infrared spectroscopy to clinically relevant levels of precision and accuracy. The system includes subsystems optimized to contend with the complexities of the tissue spectrum, high signal-to-noise ratio and photometric accuracy requirements, tissue sampling errors, calibration maintenance problems, and calibration transfer problems. The subsystems can include an illumination/modulation subsystem, a tissue sampling subsystem, a data acquisition subsystem, a computing subsystem, and a calibration subsystem. The invention can provide analyte property determination and identity determination or verification from the same spectroscopic information, making unauthorized use or misleading results less likely than in systems that use separate analyte and identity determinations. The invention can be used to control and monitor individuals accessing controlled environments.

Abstract: The present invention relates generally to non-invasive methods and apparatuses for determining analyte properties of a subject and identity characteristics of a subject. Embodiments of the present invention provide analyte property determination and identity determination or verification from the same spectroscopic information, making unauthorized use or misleading results less likely that in systems that include separate analyte and identity determinations. The invention can be used to prevent operation of automobiles or other equipment unless the operator has an acceptable alcohol concentration, and to limit operation of automobiles or other equipment to authorized individuals who are not intoxicated or drug-impaired.

Abstract: The present invention provides improved methods and apparatuses for accurate measurements using interferometers. A functional relationship between the optical path difference and time is determined from a reference signal from an interferometer. The times at which the interferometer had specific optical path differences can be determined from the functional relationship. Those times can then be used to select times at which the spectroscopic signal from the interferometer was produced at the specific optical path differences. The invention can be applied, as examples, to maintain instrument calibration, and to transfer or compare calibrations or measurements across different interferometers.

Abstract: An optical probe for non-invasively measuring an analyte property in a biological sample of a subject, comprises a plurality of illumination fibers that deliver source light from an optical probe input to a sample interface, a plurality of collection fibers that deliver light returned from the sample interface to an optical probe output, and wherein the illumination and collection fibers are oriented substantially perpendicular to the sample interface and the illumination and collection fibers are stacked in a plurality of linear rows to provide a stack of fibers arranged in a rectangular pattern. The optical probe is amenable to manufacturing on a scale consistent with a commercial product. Methods of making such probes are described.

Abstract: The present invention includes apparatuses and methods for mitigating the effects of foreign interferents on analyte measurements. The present invention comprises several interferent mitigation steps. Examples include sample cleaning procedures, detection of the presence of interferents, determination of the identity of interferents, and modification or selection of a multivariate calibration model to mitigate the effects of one or more interferents on analyte measurements. The interferent mitigation steps of the present invention can be applied individually, and in some embodiments can be applied in combination. Some examples of relevant analyte measurements include the noninvasive determination of the presence or concentration of alcohol, glucose, urea, byproducts of alcohol metabolism, and substances of abuse.

Abstract: The present invention relates generally to non-invasive methods and apparatuses for determining analyte properties of a subject and identity characteristics of a subject. Embodiments of the present invention provide analyte property determination and identity determination or verification from the same spectroscopic information, making unauthorized use or misleading results less likely that in systems that include separate analyte and identity determinations. The invention can be used to control and monitor individuals accessing controlled environments.

Abstract: The present invention provides methods and apparatuses that can improve measurement accuracy in interferometers. The invention provides methods for determining digital compensation filters that measure a frequency response or responses to be compensated, and then determining a filter target response from the inverse of the frequency response or responses. A digital compensation filter can be determined from the filter target response using a discrete sum of cosines with a phase argument. The invention also allows other desired filter responses to be integrated into the filter target response before determining the digital compensation filter.

Abstract: An apparatus and method for non-invasive determination of attributes of human tissue by quantitative infrared spectroscopy. The system includes subsystems optimized to contend with the complexities of the tissue spectrum, high signal-to-noise ratio and photometric accuracy requirements, tissue sampling errors, calibration maintenance problems, and calibration transfer problems. The subsystems include an illumination subsystem, a tissue sampling subsystem, a spectrometer subsystem, a data acquisition subsystem, and a processing subsystem. The invention is applicable, as examples, to determining the concentration or change of concentration of alcohol in human tissue.