Pyroelectric sensing apparatus substantially independent of noise output caused by mechanical shock or electrical shock
US5051701A · kind A · utility
3Cited by
2References
4Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Oct 31, 1989 |
| Grant date | Sep 24, 1991 |
| Priority date | — |
| Expiry date | Oct 31, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01K7/003
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A pyroelectric sensing apparatus is provided with an A/D convertor 29, whose digital output is examined whether continuation time period of the output from the pyroelectric element is longer than a predetermined reference time period such as 500 m sec; thereby mal-operation due to noise output from the pyroelectric element generated by mechanical shock (door close) or electric shock (pulling out a plug of other apparatus) is eliminated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.