Optical Design of Porous ZnO/TiO₂ Films for Highly Transparent Glasses with Broadband Ultraviolet Protection

Abstract

We present a design of a bilayer porous film structure on a glass substrate for the highly efficient ultraviolet (UV) protection with high visible-light transparency. To effectively block UVB (280-315 nm) and UVA (315-400 nm), titanium dioxide (TiO 2 ) and zinc oxide (ZnO) are used as absorbing layers having the appropriate coverages in different UV ranges with extinction coefficients, respectively. We show the process of refractive index (RI) matching by controlling porosity ( ). Effective RIs of porous media with TiO 2 and ZnO were calculated based on volume averaging theory. Transmittances of the designed films with different effective RIs were calculated using rigorous coupled-wave analysis method. Using admittance loci method, the film thickness was optimized in center wavelengths from 450 to 550 nm. The results show that the optimal design provides high UV shielding performance at both UVA and UVB with high transparency in the visible range. We also analyze electrical field distributions in each layer and angle dependency with 3D HSV color map.

Identification of Fungal Community Associated with Deterioration of Optical Observation Instruments of Museums in Northern Vietnam

“…The glass surface of binoculars is also coated by antireflective layers, including the outer layer consisting of low-refractive-index dielectric materials that are environmentally resistant, such as MgF 2 , Na 3 AlF 6 , CaF 2 , and LiF 2 . The inner layer is usually a dielectric with a high refractive index and good adhesion to the glass surface, including ZnO, TiO 2 , CeF 3 , and ThO 2 [26]. Moreover, a lipid layer is coated around the edges of eyepieces to prevent dirt particles from spreading and sticking to the inner glass surface and the optical system.…”

Enhanced Light Harvesting in Photovoltaic Devices Using an Edge-Located One-Dimensional Grating Polydimethylsiloxane Membrane

“…Although mankind’s energy production still depends on fossil fuels containing hydrocarbon, such as primary coal, crude oil, and natural gas with limited minable resources, the development of alternative energy resources is attracting enormous interest due to the increasing global energy demand and environmental problems associated with fossil fuels. − As an alternative source of energy, photovoltaic (PV) devices are widely used to produce electricity utilizing incident sunlight. , Among the different solar cell types, multijunction solar cells have excellent lifetime/stability and energy conversion efficiency over a broadband solar spectrum with their wide range of terrestrial and space applications. − In this substantial solar cell industry, the proper approach to protect solar cells from various threats in the external environment, such as chemicals, UV rays, and dust, must be feasibly integrated into the construction of modules. Typically, encapsulants play a key role in solar modules to serve as a protective barrier. − Moreover, for enhancing solar harvesting, encapsulation materials can be sophisticatedly structured to manage light transmission and deliver light into the active area of solar cells. So far, structural approaches, such as the use of prisms, beer steering coatings, blazed phase gratings, TiO 2 xerogel diffraction gratings, and nanocone arrays, have been reported to improve conversion efficiencies with encapsulants. − Contrary to fundamental changes in solar cell structures, since encapsulation is the final step in the modularization of solar cells, simple structure and fabrication are required to be close to commercialization.…”

Ultraviolet shielding properties of cotton fabric supported by titanium-calcium hydroxyapatite solid solution particles

“…17,22 Titanium oxide (IV) is also known to be a UV absorber 23–32 and it is used in suntan lotion to protect skin 24 and in cosmetic applications. 25 The composite of zinc oxide (ZnO) and TiO 2 26–28 and the composite of silver (Ag) and TiO 2 29 are also used as UV absorbers. TiO 2 30 and the composite of TiO 2 and polyvinylsilsesquioxane 31 were supported on cotton fabric and the UV protecting blocking ability of the cotton was investigated.…”

“…20,21 It is reported that cerium-calcium hydroxyapatite (CeCaHap) also has this UV-absorption capability. 17,22 Titanium oxide (IV) is also known to be a UV absorber [23][24][25][26][27][28][29][30][31][32] and it is used in suntan lotion to protect skin 24 and in cosmetic applications. 25 The composite of zinc oxide (ZnO) and TiO 2 [26][27][28] and the composite of silver (Ag) and TiO 2 29 are also used as UV absorbers.…”