Patent ID: 7606607

Claim:
A non-invasive device for measurement of blood saturation and heart pulse rate, comprising: a housing unit configured in the shape of a pen, said housing unit comprising: at least one light source, providing light directed toward the surface of an organ being measured, the light being reflected from said organ; a light detector spaced apart from said at least one light source and being sensitive to intensity levels of said reflected light for producing intensity signals in accordance therewith, said light detector being located on the external face of said pen, thereby allowing the housing unit to be disposed proximate to said organ; and a processing unit for processing said intensity signals received from said light detector for producing output signals, said processing unit comprising: first and second amplifiers for amplifying said intensity signals, each in accordance with a respective first and second gain amplification factor; and a processor for automatically determining said first and second gain amplification factors in adjustable fashion; wherein during a first stage, said first and second amplifiers amplify a DC signal component of said intensity signals in accordance with predetermined first and second gain amplification factors, said amplified DC signal component being subtracted from said intensity signals at an input of said first amplifier, to isolate an AC signal component of said intensity signals, and wherein during a second stage, said second amplifier amplifies said isolated AC signal component in accordance with said adjustably-determined second gain amplification factor, said processing unit producing output signals in accordance with said isolated AC signal component and said DC signal component and calculating in accordance therewith, at least one blood constituent level.