Fig. 1. Time scale of the physical phenomena of the interaction between femtosecond laser pulses and transparent materials^[7]

Fig. 2. Mechanism of laser irradiation of transparent dielectric materials. (a) Schematic diagram of laser incident transparent material^[7]; (b) electrons are excited to the conduction band^[18]

Fig. 3. Schematic diagram of manufacturing process ^[32]

Fig. 4. Diagram of 3D graphics ^[8]

Fig. 5. Optical transmission image of 3D structure ^[8]

Fig. 6. Relationship between laser etching efficiency of quartz glass and laser energy density ^[39]

Fig. 7. Comparison of the length of silica microchannels prepared by fs and ps laser in 2.5% HF etching solution for 80 min ^[40]

Fig. 8. Images of etching microchannel openings with a 600 fs laser irradiation and 2.5% HF for 80 min ^[40]

Fig. 9. Microscopic images of etched microchannels irradiated by (a) conventional pulses and (b) double pulses; relationship between etching rate of (c) conventional pulse and (d) double pulse^[43]

Fig. 10. Morphological evolution of microchannels etched in 5% HF aqueous solution by preirradiation with a pulse number varying Bessel beam. (a) Single pulse; (b) a double pulse sequence with a pulse delay of 10 ps;(c) relationship between number of pulses and depth;(d) relationship between number of pulses and rate ^[44]

Fig. 11. Etch rate of single laser modification tracks with three polarizations versus pulse energy ^[47]

Fig. 12. Comparison of etching rates of three polarized lasers (vertical, circular, and parallel)^[21]

Fig. 13. Etching rates of different solutions ^[54]

Fig. 14. Results of the etching evolution at room temperature and in aqueous HF^[21]

Fig. 15. Schematic diagram of suspension structure manufactured by laser assisted by wet chemical alkali process. (a) Femtosecond laser irradiation; (b) femtosecond laser irradiation chemical etching; (c) suspension structures ^[37]

Fig. 16. Microchannel photo obtained by 20 step dynamic displacement method^[63]

Fig. 17. Evolutions of the aperture diameter and the sag height of the microlens versus the chemical etching time^[67]