Fig. 1. Diagnosis principles. (a) System design; (b) time evolution spectrum of third harmonic signals from servo mirror recorded by spectrometer-streak camera

Fig. 2. Signal collection module design. (a) Mechanical structure diagram of signal collection module; (b) signal collection effect of signal collection module; (c) on-site arrangement of signal collection module

Fig. 3. Energy fraction diagnostic module

Fig. 4. Characteristics of energy fraction diagnostics module: (a) Gating time characteristic of ICCD; (b) response ratio calibration result of two branches in energy fraction diagnostic module

Fig. 5. Experimental conditions for DCI 2021 winter experiment. (a) Waveform conditions; (b) golden cone and laser irradiation condition (laser focusing distance from crown of 100 μm)

Fig. 6. Original diagram of diagnostic results. (a) Intensity of laser signal; (b) intensity of SBS signal

Fig. 7. Distribution of SBS backscattering energy fraction in B area. (a) Spherical crown target (laser focal spot superimposed 100 μm below crown top); (b) spherical crown target (laser focal spot superimposed 125 μm below crown top); (c) spherical crown target (laser focal spot superimposed 150 μm below crown top); (d) planar target (upper surface of laser focal spot target)

Fig. 8. Errors caused by ICCD trigger jitter and gating characteristic. (a) Time relationship among ICCD gating time characteristic, reflected laser signal part from rear surface of frequency-triple-conversion crystal and stray signal generated by primary and secondary debris shields under experimental set delay; (b) effect of ICCD trigger jitter on signal acquisition