Patent ID: 7675037

Claim:
A method for measuring THz time-domain spectrum comprising the steps of: emitting a first pulse laser beam from a first femtosecond laser device at a preset repetition frequency to excite a THz emitter to generate THz pulses, wherein the THz pulses interact with a sample to be tested before being incident on a detection device; emitting a second pulse laser beam from a second femtosecond laser device at the repetition frequency, the second pulse laser beam triggering the detection device; controlling the first femtosecond laser device and the second femtosecond laser device so that the first pulse laser beam and the second pulse laser beam emitted therefrom respectively have a varying phase difference therebetween, measuring, by the detection device, electric field intensities of the THz pulses at respective phase differences between the first pulse laser beam and the second pulse laser beam; and obtaining a THz time-domain spectrum by performing Fourier transformation of data representative of the electric field intensities.