Photoelectric sensor having an enhanced dynamic range control circuit
US5621205A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 16, 1996 |
| Grant date | Apr 15, 1997 |
| Priority date | — |
| Expiry date | Apr 16, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01J1/32
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The disclosed invention is a photoelectric sensor that is capable of resolving difficult low contrast sensing tasks by adjustment of the sensor's light source intensity, so as to prevent dark state saturation and extend the overall dynamic range of the sensor. The photosensor utilizes an enhanced dynamic (EDR.TM.) control circuit that combines the light source and offset adjustment of the DC amplifier circuit in a closed loop configuration. This connection provides an automatic reduction in the light source intensity as required to avoid saturation. Further, this is accomplished without sacrificing amplifier gain, so that the dynamic operating range of the photosensor is extended to include proper operation at very bright light levels. The EDR control circuit also includes an indicator circuit that is connected to the light intensity control circuit. The indicator circuit provides the user an indication of where in the overall dynamic range of the photosensor the offset adjustment of the DC amplifier has been set.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.