Fig. 1. (a) Experimental setup for femtosecond laser direct writing with slit shaping; (b) cross section of waveguide fabricated by conventional focusing direct writing; (c) cross section of waveguide fabricated by direct writing with slit shaping[18]

Fig. 2. Simulated light intensity distributions around focal spot with (a) conventional focusing scheme and (b) slit shaped focusing[18]

Fig. 3. Laser intensity distributions at focus of slit-shaped beams. (a) Slit width of 200 μm; (b) slit width of 2000 μm; (c) mouth type with side length of 6 μm; (d) slit width of 160 μm; (e) slit width of 2400 μm; (f) mouth type with side length of 12 μm[29]

Fig. 4. (a) Schematic of experimental setup; (b) square-shaped waveguide; near-field mode light intensity distributions of (c) s-polarized beam and (d) p-polarized beam in the waveguide[29-31]

Fig. 5. Schematic of simultaneous spatial and temporal focusing[34]

Fig. 6. (a)-(c) Simulated light intensity distributions at focus; (d)-(f) cross-sectional optical micrographs of microfluidic channels fabricated by femtosecond laser direct writing[34]

Fig. 7. Cross-sectional optical micrographs in Foturan glass with (a) conventional focusing scheme and (b) simultaneous spatial and temporal focusing (SSTF) scheme; (c) China Pavilion structure written in Foturan glass with SSTF scheme[36]

Fig. 8. (a) Schematic of setup for femtosecond laser SSTF 3D printing; (b) resolution control in SSTF 3D printing

Fig. 9. Two-photon printed image obtained by femtosecond laser SSTF. (a) Scanning electron microscope (SEM) image of 2 mm high Chinese lion sculpture; (b) digital photo of 13 mm high Terra Cotta Warrior sculpture[40]

Fig. 10. (a)(b) Cross-sectional images with chirped pulse direct writing; (c)(d) cross-sectional images with conventional focusing direct writing; (e)(f) cross-sectional images and top views of corroded microcirculation channel[50]

Fig. 11. (a) Bessel beam generated with an axicon and its intensity distribution; (b) high aspect ratio nano-channel SEM image fabricated in glass with Bessel beam[53]

Fig. 12. (a) Phase plate shaped Bessel beam and its light intensity distribution; (b) structural diagram of phase plate; cross-sectional SEM images of TSV fabricated with (c) Gaussian beam, (d) conventional Bessel beam, (e) BPP 1-shaped Bessel beam by and (f) BPP 2-shaped Bessel beam[54]