Patent ID: 6630663
Filing Date: 2003-10-07
Classification: G01N

Abstract:
An ion mobility spectrometer, comprising:a spectrometer cell having a gas inlet, a gas outlet, and a flow channel therebetween, the flow channel having a wall, a gas inlet end at the gas inlet, and a gas outlet end at the gas outlet, there being a downstream direction from the gas inlet to the gas outlet and an upstream direction from the gas outlet to the gas inlet; a field source of an electric field in the wall of the flow channel extending over a measurement region of the flow channel, the electric field extending perpendicular to the downstream direction; a plurality of sensor elements in the wall of the flow channel along the measurement region, the plurality of sensor elements including a plurality of sensor electrodes arranged in a two-dimensional array on a first side of the flow channel, and a readout circuit array integral with the plurality of sensor electrodes wherein the readout circuit array contains a preamplification circuit for each of the plurality of sensor electrodes, the readout circuit array comprising an integrated circuit operable to detect an electrical charge accumulation on each of the sensor electrodes, wherein each of the plurality of sensor electrodes arranged in a two-dimensional array may be subject to a non-uniform electric field polarity and a non-uniform electric field voltage; an air pump operable to force gas through the flow channel; a gas heater in the flow channel upstream of the source of the electric field and the plurality of sensor elements; an ionization source in the flow channel upstream of the source of the electric field and the plurality of sensor elements; and a housing enclosing the spectrometer cell, the field source, the plurality of sensor elements, the air pump, the gas heater, and the ionization source.