Ultrasonic sensor having vibrator mounted on substrate
US7622849B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 1, 2007 |
| Grant date | Nov 24, 2009 |
| Priority date | — |
| Expiry date | May 14, 2028 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10K9/122
- WIPO fieldOther consumer goods
- WIPO sectorOther fields
Abstract
An ultrasonic sensor composed of a substrate and a piezoelectric vibrator mounted on the substrate is advantageously used as a sensor for detecting a distance to an object located in front of an automotive vehicle. Ultrasonic waves transmitted from the sensor are reflected by the object, and the reflected waves are received by the sensor. Based on the reflected waves, the distance from the vehicle to the object is calculated. To reduce rigidity and thereby to lower a resonant frequency of the substrate to a desirable level, grooves are formed in the substrate. A thickness of the substrate is not reduced to maintain its mechanical strength against an impact force. A resonant frequency which is desirable to realize a sufficiently high directivity and sensitivity is obtained in this manner without enlarging a size of the ultrasonic sensor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.