초록 ▼

A capacitive transducer which comprises a pair of joined-together thin-film capacitors and a fluid-impervious container. The container may be filled with a standard solution of known composition. One of the two thin-film capacitors is immersed in the standard solution inside the container while the

A capacitive transducer which comprises a pair of joined-together thin-film capacitors and a fluid-impervious container. The container may be filled with a standard solution of known composition. One of the two thin-film capacitors is immersed in the standard solution inside the container while the other is situated outside the container. The entire transducer may be immersed in a sample, and the capacitance of the outside capacitor, which is dependent on the dielectric constant of the sample, may be compared with that of the inside capacitor after the standard solution has reached thermal equilibrium with the sample.

대표청구항 ▼

A transducer for measuring a property related to the dielectric properties of a sample fluid, said transducer being adapted for at least partial immersion in said sample fluid and comprising in combination: a first capacitive sensor comprising a plurality of interdigitated coplanar electrically cond

A transducer for measuring a property related to the dielectric properties of a sample fluid, said transducer being adapted for at least partial immersion in said sample fluid and comprising in combination: a first capacitive sensor comprising a plurality of interdigitated coplanar electrically conductive metal film electrodes deposited on an electrically insulating substrate; a second capacitive sensor comprising a plurality of intedigitated coplanar electrically conductive metal film electrodes deposited on an electrically insulating substrate; said first and second sensors being mounted so as to be (a) mechanically and electrostatically isolated from one another and (b) in direct thermal communication with one another; and an enclosure surrounding said second capacitive sensor for containing a reference fluid so that said reference fluid is (a) in contact with said second capacitive sensor, (b) in fluid and electrical isolation from said first capacitive sensor and a fluid sample contacted by said first capacitive sensor and (c) in thermal communication with a fluid sample contacting said first capacitive sensor.