Passive sensor system using ultrasonic energy
US6083165A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 29, 1998 |
| Grant date | Jul 4, 2000 |
| Priority date | — |
| Expiry date | May 29, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10K13/00
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A passive sensor system utilizing ultrasonic energy is disclosed. The passive sensor system includes at least one ultrasonically vibratable sensor and an ultrasonic activation and detection system. The sensor has at least one vibration frequency which is a function of a physical variable to be sensed. The ultrasonic activation and detection system excites the sensor and detects the vibration frequency from which it determines a value of the physical variable. The sensor includes a substrate having at least one cavity therein, and a vibratable membrane overlying the cavity. Another preferred embodiment of the sensor is a compensated sensor pair including a first sensor whose vibration frequency is responsive to the physical variable to be sensed, and a second sensor whose vibration frequency is non-responsive to the physical variable to be sensed. The second sensor provides a reference vibration frequency for compensating for the effect of other physical variables on the vibration frequency of the first sensor. Another preferred embodiment of the compensated sensor pair includes a second sensor which has a different response characteristic than that of the first sensor to the physic…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.