Hand Held Breath Analyzer

摘要

A portable breath analyzer is described including a housing that encloses a probe assembly with two probes: one responsive to the 12CO2 isotopes in a breath sample, and the other responsive to 13CO2 isotopes. Each probe includes a sample cell containing exhaled breath, a correlation cell containing a selected one of the isotopes, and a calibration cell. An IR energy source is associated with each probe. Each IR source causes propagation of infrared energy through the associated sample cell, and into the correlation cell. Gas sample probes may be aligned in series or parallel and respective correlation cells are modified to accommodate the selected probe configuration. MEMS pressure transducers may be utilized in a common wall between adjacent correlation cells to thereby sense a pressure differential caused by the absorption of pulsed IR energy in the correlation cells and to directly indicate an isotopic ratio. A MEMS transducer positioned between adjacent calibration cells may also generate a signal that is utilized to compensate for any difference in IR energy source intensity.

主权项

1. A device for determining concentrations of a selected isotope in a gas, said device comprising:
an air intake; sample cells adapted to receive an air sample; correlation cells having hermetically sealed gas chambers therein, said correlation cells including a first correlation cell having 12CO2 isotopes of carbon dioxide gas and a second correlation cell having 13CO2 isotopes of carbon dioxide gas; radiant energy sources; an isotopic analyzer; an air outtake; and air conduits coupling said air intake, sample cells and air outtake.