Patent ID: 7408360
Filing Date: 2008-08-05
Classification: G01N

Abstract:
1. A gas detector comprising: an elongated tube having: (a) means for receiving a flow of a mixture of a carrier gas and an analyte gas, (b) means for exhausting the flow of the mixture of the carrier gas and the analyte gas, and (c) a through bore free of recesses extending between said means for receiving the flow of the mixture of the carrier gas and the analyte gas and said means for exhausting the flow of the mixture of the carrier gas and the analyte gas; and a pair of excitation electrodes and an electron collector electrode: (a) mounted to said elongated tube at selected locations along the length of said elongated tube, (b) exposed to the flow of the mixture of the carrier gas and the analyte gas through said through bore, (c) said pair of excitation electrodes adapted for connection to a source of excitation voltage for: (d) said electron collector electrode adapted for connection to a source of electron collection voltage that varies in level over time for selectively collecting at particular times those electrons traveling in the plasma that have excitation levels exceeding the levels of the electron collection voltage applied to said electron collector electrode at the particular times.