We successfully fabricated Y₂O₃:RE³⁺ (RE = Eu, Tb, and Dy) core and core–shell nanophosphors by the molten salt method and sol–gel processes with Y₂O₃ core size of the order of 100~150 nm. The structural and morphological studies of the RE³⁺-doped Y₂O₃ nanophosphors are analyzed by using XRD, SEM and TEM techniques, respectively. The concentration and annealing temperature dependent structural and luminescence characteristics were studied for Y₂O₃:RE³⁺ core and core–shell nanophosphors. It is observed that the XRD peaks became narrower as annealing temperature increased in the core–shell nanophosphor. This indicates that annealing at higher temperature improves the crystallinity which in turn enhances the average crystallite size. The emission intensity and quantum yield of the Eu³⁺-doped Y₂O₃ core and core–shell nanoparticles increased significantly when annealing temperature is varied from 450 to 550 °C. No considerable variation was noticed in the case of Y₂O₃:Tb³⁺ and Y₂O₃:Dy³⁺ core and core–shell nanophosphors.

SiO₂/Nb₂O₅ multilayer thin films were designed for the special application of an aviation lighting system emitting green light. For optical components in this system to meet requirements such as a high transmittance and durability, SiO₂/Nb₂O₅ multilayer thin films of 60 individual layers were fabricated by a plasma-assisted reactive magnetron sputtering method. As a result, the transmittance spectra were confirmed to have a flat top surface and a square bandwidth. The transmittances of the SiO₂/Nb₂O₅ multilayer thin films in the range of 500 nm to 550 nm was approximately 96.14%. The reason for high transmittance was attributed to the almost matching between the designed and fabricated SiO₂/Nb₂O₅ multilayer thin films. It was found that there was little difference in the total thickness between the designed and fabricated SiO₂/Nb₂O₅ multilayer thin films without interlayer diffusion. The surface roughness and hardness of the SiO₂/Nb₂O₅ multilayer thin films on a glass substrate was 2.32 nm ± 0.19 nm and 6.6 GPa, respectively. These results indicate that SiO₂/Nb₂O₅ multilayer thin films can be applied not only to the optical filters used in aviation lighting devices, but also to various optics applications because of high transmittance.

Today, the most common way of laser sealing is using a glass frit paste and screen printer. Laser sealing using glass frit paste has some problems, such as pores, nonuniform height, imperfect hermetic sealing, etc. In order to overcome these problems, sealing using fiber types of sealant is attractive for packaging devices. In this work, (70-x)V₂O₅-5ZnO-22BaO-3B₂O₃-xM(PO₃)_n glasses (mol%) incorporated with xM(PO₃)_n concentration (where M = Mg, Al, n = 2, 3, respectively) were fabricated and their thermal, thermomechanical, and structural properties were investigated. Most importantly, for this type of sealing, the glass should have a thermal stability (ΔT) of ≥80 °C and the coefficient of thermal expansion (CTE) between the glass and panel should be 1.0 ppm/°C. The highest thermal stability ΔT of the order of 93.2 °C and 112.9 °C was obtained for the 15 mol% of Mg(PO₃)₂ and Al(PO₃)₃ doped glasses, respectively. This reveals that the bond strength and connectivity is more strongly improved by trivalent Al(PO₃)₃. The CTE of a (70-x)V₂O₅-5ZnO-22BaO-3B₂O₃-xAl(PO₃)₃ glass system (mol%) (where x = 5–15, mol%) is in the range of 9.5–15.5 (×10⁻⁶/K), which is comparable with the CTE (9–10 (×10⁻⁶/K)) of commercial DSSC glass panels. Based on the results, the studied glass systems are considered to be suitable for laser sealing using fiber types of sealant.

PbO-SiO₂-Al₂O₃-B₂O₃ (PSAB)-based glasses were prepared in order to determine the feasibility for laser sealing in the form of fiber. To reach a high quality of laser sealing, the tuning capability of CuO and Na₂CO₃ dopant concentration was examined on thermal, thermo-mechanical, and optical properties of glasses. The difference of thermal expansion coefficient was reduced with codoping of 1 wt% CuO-2 wt% Na₂CO₃ into the PSAB glass system, and it amounted to 0.34 × 10⁻⁶/K. The codoped PSAB glass system reached 100% absorption at 810 nm, which corresponds to the wavelength of laser. The glass fiber with a diameter of 180 μm was successfully pulled from the codoped PSAB glass system. The fluorine-doped tin oxide (FTO) glass substrate using the glass fiber was successfully sealed. It presented a crack-free sealed surface with a sealing strength of about 41 MPa. These results indicate that the PSAB-based glass system in the form of fiber is proved as a laser sealing material in packaging systems.