Temperature compensation in optical sensing system
US9900953B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 31, 2016 |
| Grant date | Feb 20, 2018 |
| Priority date | — |
| Expiry date | May 31, 2036 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01J2001/086
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A temperature compensation circuit for a light source (e.g., light emitting diode (LED)) whose radiant energy output decreases when ambient temperature increases includes a first circuit element for generating a first current that increases proportional to an increase in the ambient temperature, and a second circuit element for generating a second current that is first order independent of the ambient temperature. The circuit further includes a weighted current adder for generating a third current by combining the first and second currents with first and second weights applied to the first and second currents respectively. The circuit further includes a third circuit element responsive to the third current for supplying a fourth current to the light source to maintain a radiant energy output of the light source constant independent of the ambient temperature.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.