Fig. 1. Laser direct writing for gray lithography. (a) Laser direct writing principle based on point by point scanning^[51]; (b) laser direct writing principle based on field by field scanning^[51]; (c) Fourier level expansion method of "SHU" character with 249 gray scale; (d) multi-step structures fabricated by gray lithography utilizing DPSSL; (e) multi-stage structures fabricated by gray lithography utilizing LED; (f) complex micro-nano-structures fabricated by 3D laser direct writing technology

Fig. 2. Continuous frequency lithography system and its fabricated samples. (a) Schematic of UV continuous frequency lithography system; (b) schematic of Fourier transform optical system based on phase element modulation^[65]; (c) relationship between the change of photolithographic structure period and the axial movement distance of phase element^[7]; (d) SEM image of grating structure; (e) SEM image of pixel-type nano-grating structure with variable period and variable orientation; (f) SEM of circular grating; (g) SEM image of Fresnel zone structure; (h) SEM image of microporous array; (i) SEM image of micro-column array

Fig. 3. Key technologies for large-area fabrication. (a) Using DS2TI software to divide and overlap the graphics; (b) DS2TI software interface diagram; (c) Z-correction focusing; (d) schematic of 3D navigation flight exposure structure

Fig. 4. Fabrication flowchart of embedded Ni-mesh electrode^[78]

Fig. 5. Fabrication flowchart of embedded Ni-mesh electrode^[79]

Fig. 6. Photoelectric characteristics of embedded Ni-mesh electrode with different thickness^[79]. (a) Optical transmittance; (b) haze; (c) square resistance of the Ni-mesh electrodes with varying period; (d) FoM value of the Ni-mesh electrodes with varying period

Fig. 7. Mechanical properties of embedded Ni-mesh electrode^[79]. (a) Square resistance change rate of Ni-mesh electrode and ITO under different bending radius; (b) square resistance change rate of Ni-mesh electrode and ITO under bend repeatedly of 10000 times; (c) square resistance change rate of Ni-mesh electrode and ITO under scotch tape test of 100 times; (d) deformation of the square- and “T”-structured Ni-mesh electrode after bending

Fig. 8. Fabrication flowchart of composite Ag/Ni-mesh electrode^[80]

Fig. 9. Morphology and photoelectric characteristic curves of composite Ag/Ni-mesh electrode^[80]. (a) SEM image of the Ag/Ni-mesh electrodes under various Ni deposition time; (b)-(d) thickness and square resistance, optical transmittance, and haze of the Ag/Ni-mesh electrodes under various Ni deposition time

Fig. 10. Fabrication process and morphology of the freestanding metal mesh electrode^[81]. (a) Fabrication flowchart of freestanding metal mesh electrode; (b) SEM of Ni mesh electrode surface and side

Fig. 11. Photoelectric characteristics of freestanding Ni-mesh electrode^[81]. (a) Optical transmittance; (b) square resistance and FoM; (c) image of the freestanding Ni-mesh electrode

Fig. 12. Fabrication process for the designed absorption device based on pixelated lattice structure^[82]

Fig. 13. Colorful displays incorporating pixelated nanostructures^[83]. (a) Rainbow color display; (b) colorful school emblem; (c) cherry pattern

Fig. 14. Structure of electrochromic device, color change effect diagram after applying voltage, and cycle stability of the device^[89]

Fig. 15. Vector light field display based on nano-grating^[7]. (a) Mechanism diagram of nano-grating realizing views control; (b) schematic of nano-grating arrangement; (c) SEM image of nano-grating with scale of 20 μm; (d)-(f) 3D perspective images from different views

Fig. 16. Vector 3D display based on blazed grating^[95]. (a) 3D display mechanism diagram of vector light field; (b)(c) SEM image of blazed grating; (d)(e) 3D display effect under different views

Fig. 17. True 3D display of virtual reality fusion based on vector light field^[96]. (a) Schematic of augmented reality 3D display; (b) mechanism of multi view 3D display; (c) naked eye augmented reality 3D display; (d)-(f) mermaid 3D images observed from left, middle, and right views; (g)-(i) 3D images of unfolded book observed from left, middle, and right views

Fig. 18. Thickness, square resistance, transmittance, and shielding effectiveness of composite Ag/Ni-mesh electrode deposited at different time^[80]

Fig. 19. Transmittance and shielding effectiveness of self-supporting Ni-mesh electrode^[81]

Fig. 20. Structure diagram of double-layer Ni-mesh device^[101]. (a) Fabrication process; (b) shielding mechanism; (c) side view of shielding mechanism

Fig. 21. Optical transmittance and shielding efficiency of the single-layer and double-layer Ni-mesh electrodes^[101]. (a) Transmittance of the single-layer and double-layer Ni-mesh electrodes after PVA coating; (b) shielding effectiveness and transmittance of single-layer and double-layer Ni-mesh electrodes with various grid space; (c)(d) transmittance and shielding effectiveness of the double-layer Ni-mesh electrodes under different double-layer grid spacing

Fig. 22. Physical diagram, permeability, electrochemical energy storage, and bending resistance of all solid state supercapacitor based on Ag-mesh electrode^[107]

Fig. 23. Performance characterization of supercapacitor based on flexible transparent self-supporting electrode^[79]. (a) Self-supporting Ni-mesh electrode and the transmittance of supercapacitor based on this; (b) electrochemical energy storage properties of the supercapacitor after folding

Fig. 24. Optoelectric properties, micro-nano-structure and solid state supercapacitor, electrochemical energy storage and bending resistance of flexible transparent conductive film based on Ni-mesh^[108]

Fig. 25. Transmittance, gas permeability, and energy storage performance of supercapacitor based on self-supporting electrode^[109]

Fig. 26. Characterization of MnO₂@Au-Ni electrode performance^[110]. (a) SEM image of the MnO₂@Au-Ni electrode under various scale bar; (b) transmittance of the Ni-mesh electrode and MnO₂@Au-Ni electrode; (c)(d) cyclic voltammetry curves and areal capacitance of the supercapacitor structed by MnO₂@Au-Ni electrode with varying scanning rate