Fig. 1. Spectrum of frequency modulation small- bandwidth pulse (0.3 nm bandwidth)

Fig. 2. Time waveforms of different points in near field of the frequency modulation pulse beam

Fig. 3. Field distributions of single-mode fiber coupling. (a) Diffraction field; (b) fiber mode field

Fig. 4. Schematic of waveform test system

Fig. 5. Lens array. (a) Lens array object; (b) position relation between lens array and measured beam

Fig. 6. Field distributions of microlens array coupling. (a) Distribution of diffracted light field in sampling aperture of microlens; (b) mode field distribution of graded multimode fiber

Fig. 7. Nonlinear effect test results of OM5 fiber

Fig. 8. Schematic of verification experiment of frequency modulation pulse waveform measurement scheme

Fig. 9. Verification results of frequency modulation pulse waveform measurement scheme. (a) Input waveform without amplitude modulation; (b) input waveform with amplitude modulation