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: A diagnosis system, which comprises a monitor, comprising a detector providing multiple reflectance readings in an array of individual locations, registering an analytical cartridge in the monitor at a fixed location and orientation relative to the array, and determines and displays analytical results from reflectance readings; and an analytical cartridge, comprising a liquid impervious housing, a sample application site in the housing located outside the monitor when the cartridge is registered in the monitor by the means for registering, one or more reflectance reading sites in the housing that register with one or more of the locations in the array, a capillary pathway in the housing leading from the sample application site to each of the reflectance reading sites, and a reflectance matrix located in at least one of the reflectance reading sites.