Method and apparatus to sense temperature of thermal tuning elements in tunable optical devices
US6798800B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 30, 2002 |
| Grant date | Sep 28, 2004 |
| Priority date | — |
| Expiry date | Dec 30, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01K7/20
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A tunable optical unit includes a resistive temperature device (RTD), a thermal tuning device and a measurement circuit. The RTD has a resistance dependent on a temperature of the thermal tuning device. The measurement circuit outputs a signal that is dependent on the resistance of the RTD. The signal is used to control the temperature of the thermal tuning device in tuning the tunable optical unit. A reference resistance can be connected in series with the RTD to make ratio-metric measurements to determine the RTD's resistance (and hence the temperature of the tuning elements) without having to know the value of the current conducted through the RTD and to reduce sensitivity to fluctuations in the excitation signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.