Fig. 1. Nodular defect morphology under laser irradiation

Fig. 2. Distribution of nodular defects in gratings

Fig. 3. Grating damage morphology and electric field distribution caused by nodular defects at different positions of s-polarized Ti:Sapphire laser with an incident angle of 65° and a pulse duration of 32 fs^[41]

Fig. 4. Damage evolution of grating film under irradiation of 120 fs, 796 nm, 10 Hz laser^[40]. (a)(d) nano bumps; (b)(e) surface roughness; (c) nano cracks; (f) film falling off

Fig. 5. Distribution of grating films

Fig. 6. Grating damage morphologies of Ti: Sapphire laser with different laser injection energy and film deposition methods at a frequency of 1 kHz and a pulse duration of 60 fs^[50]

Fig. 7. Damage morphology of ACG prepared by electron beam evaporation with Ti: Sapphire laser at frequency 1 kHz and pulse duration 60 fs^[51]

Fig. 8. Changes of LIDT of SiO₂ sol-gel film with pollution time^[63]

Fig. 9. Damage morphologies of MMDG with 1.48 J/cm₂ of particulate pollutants at pulse duration of 8.6 ps^[64]

Fig. 10. Typical pulse compression grating preparation process

Fig. 11. Laser-induced damage thresholds of HfO₂ films at annealing temperatures of 353 K, 423 K, 503 K and 573 K^[65]

Fig. 12. Elements content of the surface of the substrates^[69]

Fig. 13. Damage state of Ti: Sapphire laser in the state of single-pulse and double-pulse radiation at a frequency of 10 Hz and a pulse duration of 35 fs^[70]

Fig. 14. SEM images of grating before and after cleaning^[76]

Fig. 15. Damage probability of introduced gas under vacuum and different pressures^[80]

Fig. 16. Scientific and technical issues in the research on laser-induced damage of pulse-compressed gratings