Abstract: A device and method are provided for use with a noninvasive optical measurement system, such as a thermal gradient spectrometer, for improved determination of analyte concentrations within living tissue. In one embodiment, a wearable window is secured to a patient's forearm thereby isolating a measurement site on the patient's skin for determination of blood glucose levels. The wearable window effectively replaces a window of the spectrometer, and thus forms an interface between the patient's skin and a thermal mass window of the spectrometer. When the spectrometer must be temporarily removed from the patient's skin, such as to allow the patient mobility, the wearable window is left secured to the forearm so as to maintain a consistent measurement site on the skin. When the spectrometer is later reattached to the patient, the wearable window will again form an interface between the spectrometer and the same location of skin as before.

Abstract: A device and method are provided for use with a noninvasive optical measurement system, such as a thermal gradient spectrometer, for improved determination of analyte concentrations within living tissue. In one embodiment, a wearable window is secured to a patient's forearm thereby isolating a measurement site on the patient's skin for determination of blood glucose levels. The wearable window effectively replaces a window of the spectrometer, and thus forms an interface between the patient's skin and a thermal mass window of the spectrometer. When the spectrometer must be temporarily removed from the patient's skin, such as to allow the patient mobility, the wearable window is left secured to the forearm so as to maintain a consistent measurement site on the skin. When the spectrometer is later reattached to the patient, the wearable window will again form an interface between the spectrometer and the same location of skin as before.

Abstract: An analyte detection system includes a first wearable module, a detector, and a processor. The first wearable module has an optical input through which electromagnetic radiation may enter said first wearable module. The first wearable module is configured to be worn on and engage a living wearer's body such that electromagnetic radiation omitted by the body of the wearer can enter the first wearable module via the optical input. The detector is in optical communication with the optical input. The processor is in communication with the detector. The processor is configured to estimate the concentration of an analyte in the wearer's tissue based on the emitted electromagnetic radiation.

Abstract: A device and method for selecting and stabilizing proper sites for the measurement of the concentration of an analyte, for example glucose, within the tissue of a subject or patient are disclosed. One embodiment of the device immobilizes the subject's forearm and finger, thereby stabilizing measurement sites thereon for exposure to a noninvasive monitor which captures analyte concentration data within the subject's skin. The method involves the choice of a location on the subject's body at which to take the analyte measurement, preferably based on the amount of time that has elapsed since the last time the subject ate.

Abstract: A device and method are provided for use with a noninvasive optical measurement system, such as a thermal gradient spectrometer, for improved determination of analyte concentrations within living tissue. In one embodiment, a wearable window is secured to a patient's forearm thereby isolating a measurement site on the patient's skin for determination of blood glucose levels. The wearable window effectively replaces a window of the spectrometer, and thus forms an interface between the patient's skin and a thermal mass window of the spectrometer. When the spectrometer must be temporarily removed from the patient's skin, such as to allow the patient mobility, the wearable window is left secured to the forearm so as to maintain a consistent measurement site on the skin. When the spectrometer is later reattached to the patient, the wearable window will again form an interface between the spectrometer and the same location of skin as before.

Abstract: In accordance with one embodiment there is provided a method of providing a known spectrum to a noninvasive optical detection system of the type having a window for receiving infrared energy. The method comprises affixing a standard to the window. The standard comprises a body formed from a material having known and stable spectral properties. The method further comprises placing at least a portion of the body directly against the window, and operating the optical detection system to detect an emission spectrum of the body. In accordance with another embodiment an infrared spectrometer comprises a window for receiving infrared energy. The window has an exposed surface. The infrared spectrometer further comprises a standard comprising a body formed of a material having known and stable spectral properties. At least part of the body is removably disposed directly against the exposed surface of the window.

Abstract: A disposable anti-fog airway adapter for use with a mainstream respiratory gas analyzer which provides a measurement of a patient's inhaled and exhaled gases. The airway adapter includes windows that are constructed of a thin, low heat capacity plastic that rapidly equilibrates to the temperature of the warm moist gases in the patient breathing circuit. In addition, the inside of the windows is also coated with an anti-fog surfactant either by laminating an anti-fog film with the window plastic prior to attaching the window to the airway adapter body or by first attaching the window to the airway adapter body and then applying the surfactant to the airway adapter after the window film is bonded in place so that the surfactant coats the entire inside of the adapter.

Abstract: A method and apparatus for monitoring glucose, ethyl alcohol and other blood constituents in a noninvasive manner. The measurements are made by monitoring infrared absorption of the desired blood constituent in the long infrared wavelength range where the blood constituent has a strong and distinguishable absorption spectrum. The long wavelength infrared energy emitted by the person as heat is monitored and the infrared absorption of particular constituents in the blood (such as glucose or blood alcohol) is measured at characteristic infrared absorption wavelengths for those constituents. The measurements are preferably synchronized with systole and diastole of the cardiac cycle so that the signal contribution caused by veins and tissues (which do not pulse) may be cancelled when a ratio of the detected signals is taken. The concentration of the blood constituents are then determined in accordance with a polynomial equation.

Abstract: An anesthetic agent analyzer having six or more independent analytical channels, where each channel comprises a first thermopile which receives incident infrared radiation and a second thermopile behind the first thermopile which is blocked from the incident infrared radiation and thus serves as a reference for detecting ambient temperature variations. The first and second thermopiles are connected in a "parallel opposed" fashion so that the effects of ambient temperature variations automatically cancel and the detectors may be readily configured in a detector package. The anesthetic agent analyzer of the invention is designed for use with a wideband infrared radiation source so that anesthetic agents having characteristic absorption bands in the far infrared wavelength range (6-15 microns) may be more readily detected and discriminated.

Abstract: An infrared source which provides a miniature, highly stable and efficient source of infrared energy for use with infrared detectors and the like. The infrared source of the invention incorporates a platinum resistance temperature detector (RTD) which is integrated with the heater element to provide a means of electronic servo control of the heater temperature. The heater element and the RTD are tightly coupled thermally to provide accurate, continuous tracking and control of the heater temperature. The infrared source design provides excellent infrared energy output with less than one watt input power to the heater.