Fig. 1. SEM images and nanoparticle microscopic models. (a) Film cross-section of nanoparticles without agglomeration; (b) simplified model of nanoparticles without agglomeration; (c) film cross-section of nanoparticles with agglomeration; (d) simplified model of nanoparticles with agglomeration

Fig. 2. Particle size distribution and optical parameter profiles of materials. (a) Particle size distribution of TiO₂; (b) refractive index and extinction coefficient of TiO₂; (c) refractive index and extinction coefficient of TPU

Fig. 3. Variations of TiO₂ particle film spectra with filling factor. (a) Transmittance; (b) reflectance

Fig. 4. Variations of TiO₂ particle film spectra with nanoparticle diameter. (a) Transmittance; (b) reflectance

Fig. 5. Spatial distributions of electric field for wavelengths of 200 nm, 800 nm, 1600 nm, and 3000 nm. (a) d=100 nm; (b) d=200 nm; (c) d=300 nm

Fig. 6. Spatial distributions of electric field for light with wavelength of 1500 nm. (a) Single particle diameter d=100 nm; (b) hierarchical particle diameter d=(100±50) nm; (c) agglomerated particle structures

Fig. 7. Transmittance curves. (a) Comparison of transmittance of three structures; (b) comparison of simulation results with experimental results

Fig. 8. Variation of transmittance with angle of incidence θ. (a) TE mode; (b) TM mode

Fig. 9. Spatial distributions of electric fields with incidence angles θ of 0°, 20°, 40°, and 60°. (a) Wavelength of 300 nm; (b) wavelength of 2000 nm