High-Frame-Rate Spectrum Measurement for Ultrafast Optical Pulses Based on Optical Signal Processing

The pulse-by-pulse single-shot spectrum measurement for high-repetition rate optical pulses with femtosecond or picosecond pulse width is important for capturing non-repetitive and rare phenomena of substances. Conventional optical spectrum analyzers cannot acquire the spectrum for each pulse at high-repetition rate without missing due to the low processing speed. Several highspeed optical signal processing techniques can help to acquire pulse-by-pulse single-shot spectrum. The highspeed spectrum measurement using a fiber chromatic dispersion-based time stretch dispersive Fourier Transform (TS-DFT) technique is a powerful tool for such measurements. In this paper, we present a record pulse-by-pulse single-shot spectrum measurement for 1 GHz repetition-rate optical pulses with a less than 67-pm spectral resolution based on the TS-DFT technique.