Photodetector circuit for an electronic sprayer
US5763873A · kind A · utility
56Cited by
60References
15Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 28, 1996 |
| Grant date | Jun 9, 1998 |
| Priority date | — |
| Expiry date | Aug 28, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01J3/501
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An agricultural implement for spraying herbicide on weeds in a field without spraying herbicide on bare soil includes a photodetector circuit. The photodetector circuit includes a photodetector and an active filter. The photodetector is not AC coupled in parallel with an inductor/capacitor resonant circuit which tunes the active filter. As a result, changes in photodetector capacitance due to changes in ambient lighting conditions are not impressed across the resonant inductor/capacitor circuit and therefore do not adversely change the frequency and phase characteristics of the photodetector circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.