Miniaturized ion mobility spectrometer sensor cell

DETAILED DESCRIPTION To accomplish the above and other objectives, the present invention provides for an improved ion mobility spectrometer for chemical warfare agents, and in particular to a spectrometer developed by Environics, Oy of Finland.
The present ion mobility spectrometer comprises an improved sensor cell that includes an air flow heater assembly, an ionization assembly and a field electrode and detector assembly printed circuit assembly.
The heated air flow assembly comprises a cover having an air inlet, an ambient temperature sensor, a thin-film heater element, a heater frame, a heated air sensor, and a heater channel formed therein.
The ionization assembly comprises a nuclear ionization source attached to a holder, a lid, and an ionization channel formed therein that is coupled to the heater channel.
The field electrode and detector assembly printed circuit assembly comprises a field electrode printed circuit board, a detector electrode printed circuit board, and detector electronics.
The field electrode printed circuit board has a plurality of field electrodes disposed on a bottom surface thereof.
A gasket is disposed between the field electrode and detector electrode printed circuit boards.
The detector electrode printed circuit board has plurality of detector electrodes disposed on a top surface thereof.
The detector electronics processes current outputs of the detector electrodes to generate histogram of ion currents that identify mobilities of chemical species tested by the ion mobility spectrometer.
One of the objectives of the present invention is to reduce the size of the existing detector cell manufactured by Environics, Oy from its present size of 11".
times.
4".
times.
11" to a size of approximately 40 in.
sup.
3 or less.
To accomplish this goal, the Environics, Oy sensor cell, which has a size of approximately 6".
times.
4".
times.
2" has been miniaturized using the principles of the present invention to occupy a small amount of its normal space.
At the same time, the performance of the sensor has not been compromised