Temperature measurement with error suppression based on dual-wavelength fiber ring laser sensor

•A temperature measurement method with error suppression is performed by a dual-wavelength FRL with an intracavity Sagnac interferometer.•Adual-wavelengthfilter is formed by cascading two DWDMs.•Theintensity difference of two peaksis measuredby difference method.•Compared with single-wavelength configuration, the measurement error of dual-wavelength is reduced from 0.443% to 0.066%.