Patent ID: 6928311

Claim:
A measuring device for non-invasively measuring levels of constituents in blood and tissue in a subject, the measuring device comprising: (a) a housing having an opening for receiving a hand of the subject; (b) a polychromatic light source that emits a broad spectrum of light in the near infrared range and adjacent visible light; (c) a part receptor shaped for receiving a finger of the subject, the part receptor being located relative to the light source so that when the finger of the subject is placed in the part receptor, the light source can be activated and light from the light source can be directed onto the finger, the part receptor being shaped to receive the finger in close alignment, so as to reduce extraneous light; (d) a light receptor for collecting a continuum of wavelengths over the broad spectrum of light after the broad spectrum of light has been directed onto the finger; (e) a dispersion element coupled to the light receptor for dispersing light collected by the light receptor into a dispersed spectrum of component wavelengths; (f) a photodetector coupled to the dispersion element for taking absorbance measurements from the dispersed spectrum and producing a measurement signal; (g) a communications interface connectable to an external computer for communicating the measurement signal to the external computer, and (h) a power interface connectable to an external stabilized power source.