초록 ▼

A device for sensing the presence of and measuring the concentration of a specific non-aqueous particle or gas material in an environment, the device comprising an interdigitated capacitor having at least a pair of selected covering layers thereupon, said pair of layers comprising a first passive el

A device for sensing the presence of and measuring the concentration of a specific non-aqueous particle or gas material in an environment, the device comprising an interdigitated capacitor having at least a pair of selected covering layers thereupon, said pair of layers comprising a first passive electrically insulative layer and a second material layer having a spacial relationship to said first layer, said second layer selectively permeable to the specific material to be sensed and measured; said second coating, when juxtaposed said first coating, selectively permitting permeability of the particular material sought to be sensed and measured, and when spaced apart, permitting passage through of the specific material in order that the material may migrate to the proximity of the first coating and thereby be sensed and measured. The presence of the specific material modifies the dielectric constant of the dielectric in the interdigitated capacitor electric field and thus the capacitor\s capacitance, whereupon the interdigitated capacitor\s capacitance is compared with a proximate temperature sensing interdigitated capacitor in a capacitance sensing circuit and by the change of the capacitance, the presence and concentration of the specific material determined.

대표청구항 ▼

A capacitive detection device for sensing the presence of and measuring the concentration of a specific gas in a gaseous fluid, the device comprising: a capacitor having a plurality of spaced apart electrically conductive electrodes, said electrodes adapted to receive an electrical input and emit an

A capacitive detection device for sensing the presence of and measuring the concentration of a specific gas in a gaseous fluid, the device comprising: a capacitor having a plurality of spaced apart electrically conductive electrodes, said electrodes adapted to receive an electrical input and emit an electrical output to create a capacitive electric field therebetween; a first electrically insulative material layer passive to the gaseous fluid covering said electrically conductive electrodes; and a second material layer covering said first material layer, said second material layer being selectively permeable to the specific gas in the gaseous fluid whereby the specific gas may be sensed and its concentration measured as a consequence of its entering the electric field between said electrodes and thereby changing the capacitance between said electrodes.