Fig. 5: Principle and experimental diagram of the time lens spectrogram (TLS) and Talbot array illuminator spectrogram (TAIS) scheme.
From: Linear optical wave energy redistribution methods for photonic signal processing
a The TLS involves an array of adjacent time lenses followed by GVD to time map the frequency spectrum of each of the temporal sections of the signal under test (SUT) under each time lens aperture along the corresponding temporal slot, ensuring real-time spectral analysis of consecutive time sections of the SUT in a gapless and continuous manner. b The scheme of a real-time spectrogram analysis based on similar principles but using Talbot phase modulation, implementing a TAIS. In the shown example, the scheme is utilized for the analysis of microwave signals (SUT), e.g., as captured by a suitable antenna, by simply modulating this SUT on a continuous-wave (CW) light beam (optical carrier).
