Fig. 1. Classic dynamic scenes captured by high-speed photography. (a) Galloping horse captured by Muybridge^[10]; (b) shockwave formed by a high-speed flying bullet captured by Mach^[11]; (c) instant of a hummingbird flapping its wings captured by Edgerton^[13]; (d) moment of a falling milk droplet forming the “milk crown” captured by Edgerton^[13]

Fig. 2. Roadmap of the development of representative high-speed, ultra-high-speed, and extreme-high-speed imaging technologies

Fig. 3. Classification of representative ultra- and extreme-high-speed optical imaging technologies

Fig. 4. Differences in data transfer modes between CCD and CMOS

Fig. 5. Representative ICCD ultrafast cameras. (a) PCO.DicamC4UHS^[75]; (b) IMACON 200^[3]; (c) XXRapidFrame^[3]

Fig. 6. Two types of solid-state imaging devices of ISIS CCD and high-speed CMOS. (a) Charge transfer and storage structure of ISIS CCD^[76]; (b) CMOS chip based on pixel-level trench capacitor storage array^[17]

Fig. 7. Principle and application of the STEAM^[46]. (a) Schematic of the STEAM optical path system; (b) flow process of metal microspheres in a hollow optical fiber recorded by the STEAM

Fig. 8. Principle and applications of the STAMP^[36]. (a) Schematic of the STAMP optical path system; (b) experimental setup for ablation imaging; (c) plasma glow phenomenon recorded by the STAMP

Fig. 9. Principle and application of the SF-STAMP^[43]. (a) Schematic of the SF-STAMP optical path system; (b) laser-induced phase transition process of Ge₂Sb₂Te₅ sample captured by the SF-STAMP

Fig. 10. Working principle of a streak camera^[78]. (a) Schematic of the streak camera's working process; (b) schematic of the timing sequence during operation

Fig. 11. Principle and application of the TLA-SC^[77]. (a) Schematic of the TLA-SC optical path system; (b) three-dimensional schematic of a tilted lens around the optical axis; (c) measurement results of aluminum ring irradiated by femtosecond laser recorded by the TLA-SC; (d) three representative frames extracted from the complete captured image

Fig. 12. Principle and application of the FINCOPA^[40]. (a) Schematic of the FINCOPA optical path system; (b) grating image captured by the FINCOPA; (c) ultrafast rotating light field captured by the FINCOPA

Fig. 13. Principle and application of the SS-FDT^[51]. (a) Schematic of the SS-FDT optical path system; (b) phase fringes caused by continuously changing refractive index profiles; (c) propagation of femtosecond laser pulses in glass recorded by the SS-FDT

Fig. 14. Principle and application of the CUP^[37]. (a) Schematic of the CUP optical path system; (b) reflection, refraction, and propagation of pulses captured by the CUP

Fig. 15. Principle and application of the T-CUP^[38]. (a) Schematic of the T-CUP optical path system; (b) time-focusing phenomenon of laser pulses captured by the T-CUP

Fig. 16. Principle and application of the CUSP^[39]. (a) Schematic of the CUSP optical path system; (b) phenomenon of laser pulse scanning and illuminating letters captured by the CUSP

Fig. 17. Principle and application of the FRAME^[50]. (a) Schematic of the FRAME optical path system; (b) schematic of an imaging device for recording femtosecond pulse propagation in a medium; (c) reconstructed imaging results of femtosecond laser pulses propagating in CS₂ liquid

Fig. 18. Principle and application of the CUST^[61]. (a) Schematic of the CUST optical path system; (b) flying laser pulse captured by the CUST

Fig. 19. Principle and simulation results of the biomimetic ultra-high-speed imaging^[59]. (a) Schematic of the imaging optical path system; (b) distribution of step heights in the delay unit and schematic of the structured light interference pattern; (c) schematic of the composite system generated by assembling the module in Fig.19(b); (d) superimposed pattern of a resolution chart, frequency domain distribution, and simulated reconstructed single-frame image recorded by the biomimetic imaging system

Fig. 20. Principle and imaging results of the STORM. (a) Schematic of STORM super-resolution principle^[88]; (b) imaging results of the STORM^[89]

Fig. 21. Principle and imaging results of the STED. (a) Schematic of STED super-resolution principle^[92]; (b) imaging results of the STED^[93]

Fig. 22. Principle and imaging results of the TCSRM^[96]. (a) Schematic of the TCSRM; (b) original imaging results recorded by the detector; (c) intensity distribution of the first frame image reconstructed by the TCSRM in the horizontal and vertical directions; (d) image sequence reconstructed by the TCSRM

Fig. 23. Schematic and reconstructed image of the SIC-CUP^[97]. (a) Schematic of the SIC-CUP system; (b) reconstructed imaging results based on the SIC model

Fig. 24. Flowchart of the PnP-ADMM and the reconstructed images of different algorithms^[47]. (a) Flowchart of the PnP-ADMM; (b) reconstructed images of different algorithms

Fig. 25. Reconstructed images and a comparison of PSNR and SSIM parameters of different algorithms in various scenes^[101]

Fig. 26. Reconstructed image performance of different reconstruction algorithms in different scenes^[103]

Fig. 27. Comparison of reconstructed image results between the TwIST and the MPPN in different scenes^[104]