The application provides a
temperature measurement method and device based on single-cavity double
optical comb, and belongs to the technical field of
laser absorption spectrum. A single-cavity double
optical comb generation module generates a probe
optical comb and a
local oscillator optical comb with slightly different repetition frequencies; a
temperature control module makes the single-cavity double optical comb generation module work in a constant temperature environment; the probe optical comb and the
local oscillator optical comb are respectively amplified and spectrally broadened; the two optical combs are combined through a 2*1
optical fiber coupler, then enter an optical band-pass filter for filtering; the filtered double optical combs pass through a gas medium to be measured, and an interference
signal of
asynchronous sampling between the double optical combs is obtained through a
photodetector; a
signal acquisition and
processing module is used to acquire the interference
signal filtered through an electrical low-pass filter, so that a gas absorption spectrum is obtained; finally, through
frequency domain difference and
time domain separation, a multi-spectrum fitting method is used to solve the gas temperature. The application combines the advantages of the single-cavity double optical comb, such as high
spectral resolution, high coherence and wide spectrum, and the advantages of the multi-spectrum
fitting algorithm, such as high robustness, strong anti-
noise ability and strong
immunity to baseline, so that the gas absorption spectrum measurement and
temperature measurement are realized, and the application has a wide application prospect.