Papers by Keyword: Transmittance

Abstract: Multilayer structure with SnO₂/Ag//SnO₂ was prepared on glass substrates by sequential using RF/DC magnetron sputtering at room temperature. In order to estimate and compare with the experimental results in advance, EMP (Essential Macleod Program) simulation program was adopted. EMP simulation results suggested that the multilayered thin film of SnO₂ (30 nm)/Ag (10 nm)/SnO₂ (30 nm) exhibited the highest visible transmittance of 88.8 % at 550 nm, whereas experimentally measured transmittance showed 85.5 %, somewhat lower than simulation data. Even though most of films exhibit transmittance of about 88 % at 550 nm wavelength, there are some distinct differences between the experimental and simulated results. Sheet resistance (Rs) were almost constant and the lowest Rs value about 9.51 Ω/sq was acquired at the multi layers with the structure of SnO₂ (30nm)/Ag (10nm)/SnO₂ (30nm). However, the resistivity of the SnO₂/Ag/SnO₂ multi layer film increased systematically with increasing thickness of SnO₂ layer from 30 to 50 nm. SnO₂/Ag/SnO₂ multilayer with 50 nm of SnO₂ thickness resulted in a decrease of Φ_TC due to decrease of transmittance. The highest Φ_TC value of SnO₂/Ag/SnO₂ film was obtained at a SnO₂ thickness of 35 nm.

Abstract: A series of zeolite-derived silica glasses have been fabricated through the order-disorder transition process of zeolites using spark plasma sintering (SPS). The samples were characterized by UV-VIS-NIR transmittance, Raman spectra and Vicker’s hardness. Results showed that the transmittance of zeolite-derived silica glass samples increased with the sintering temperature increasing. The transmittance of the sample prepared at 1300°C was lower than 5%. The highly transparent samples could be obtained when the sintering temperature was above 1350°C. The transmittance of these samples was higher than 80% in the range of 780~1700nm and 60% in the UV-vis range of 250~780nm. One absorption band at 300nm can also be observed in the spectrum. The reason of this phenomenon could be ascribed to a few left crystallite fragments of ZSM-5. The Raman spectra showed that the bands at 378 and 292cm^-1of ZSM-5 were significantly weakened and then disappeared with increasing the sintering temperature and the bands at 489 and 600cm^-1 of silica glass became more apparent. The Raman spectra of the samples obtained above 1350°C were the same as that of the fused silica glass. The Vicker’s hardness of as-prepared samples increased with the rising of the sintering temperature. The maximum hardness of 7.31 GPa was achieved for the sample sintered at 1400°C. The fracture toughness of samples increased from 0.83 MPa·m^1/2 to 2.37 MPa·m^1/2 with the sintering temperature increasing.

Abstract: This work is devoted to investigation of the way light transmittance of drying drop of Fe₂O₃ nanocolloid deposited on flat surface changes as liquid evaporates. According to results of transmitted light intensity measuring it is assumed that drying process can be divided into separate stages each being characterized by particular quality level of ability to transmit light because of different behavior and, thus, density of suspended nanoparticles inside the droplet. The last stage ends by forming of a ring-shaped pattern (known as “coffee ring”). Temperature of the surface was being changed by applying a varying potential difference to lower layer of transparent substrate made of ITO. Time dependences of integral transmitted light intensity for every single temperature are represented in graphs. They are compared with dependences for water drops of the same volume.

Abstract: Polydimethylsiloxanes (PDMS), (CH₃)₃SiO-[Si(CH₃)₂O]_n-Si(CH₃)₃, known as silicone oil is a tamponade liquid which is very important in vitreoretinal surgery, especially in the treatment of complicated retinal detachment. Here, we investigated the optical properties and structure of silicone oil with high viscosity silicone oil of 5500 cSt and low viscosity silicone oil of 1300 cSt in order to understand the changing of physical properties of silicone oil before and after using in vitreoretinal surgery as a tamponade liquid and analyze the relationship between the tamponade duration and changed in silicone oil properties. From UV-Vis spectroscopy and refractometer measurement, it is found some changes in transmittance and refractive index values in both silicone oil after using as a tamponade liquid. From fourier transform infrared (FT-IR) spectroscopy, some additional of functional groups of N-H and O-H bond are observed at 1634.5 cm^-1 and 3435.7 – 3764.5 cm^-1, respectively. The changes of optical and structure properties of silicone oil after using as a tamponade liquid are assumed to be responsible in emulsification of silicone oil and affect the transmittance quality at visible light spectrum. However, in this study, there is no linear corelation between tamponade duration and changed in silicone oil properties.

Abstract: LYSO:Ce crystal is one of efficient scintillation materials with high light output and short decay time. LYSO:Ce crystal grown by Czochralski method can be affected by annealing treatments. In present work, annealing treatments in different atmosphere (air, N₂ and H₂) were carried out on the LYSO:Ce crystals to investigate the effect on the optical and luminescence properties after annealing. The optical transmittance, excitation and emission spectrum, and the decay time have been attained at room temperature. Luminescence efficiency has been presented by the integrated area of emission spectra under ultraviolet (UV) excitation. It is found that annealing treatments almost do not affect the optical transmittance. Annealing in N₂ atmosphere has no noteworthy effect on the luminescence intensity of LYSO:Ce crystals, but increases much annealing in H₂ atmosphere, dramatically decreases the luminescence intensity after annealing in air. In addition, the decay time of LYSO:Ce crystals are affected by annealing treatment either in air or in H₂ atmosphere.

Abstract: This work characterizes the mechanical and opto-electric properties of Aluminum-doped zinc oxide (AZO) thin films deposited by atomic layer deposition (ALD), where various depositing temperature, 100, 125, 150, 175, and 200 °C are considered. The transmittance, microstructure, electric resistivity, adhesion, hardness, and Young’s modulus of the deposited thin films are tested by using spectrophotometer, X-ray diffraction, Hall effect analyzer, micro scratch, and nanoindentation, respectively. The results show that the AZO thin film deposited at 200 °C behaves the best electric properties, where its resistance, Carrier Concentration and mobility reach 4.3×10^-4 Ωcm, 2.4×10²⁰ cm^-3, and 60.4 cm²V^-1s^-1, respectively. Furthermore, microstructure of the AZO films deposited by ALD is much better than those deposited by sputtering.

Abstract: Corneal transplantation is the only effective way to repair the damaged corneal tissue and solve the problem of insufficient donor cornea and immune rejection. Biocompatibility and stable transparent are necessary conditions of corneal stromal cells carrier. In this paper, the acetamide/silk (AC/SF) composite membranes are studied to be applied in corneal repair material. AC/SF membranes with different blending proportions had stable transparency, good cell compatibility. X-ray diffraction was used to investigate the structure of the composite films. The acetamide inhibited the formation of large crystalline particles, changed the crystal structure of silk fibroin and made the random coil structure convert to Silk I or Silk II. Therefore, acetamide was not only crosslinking agent but also crystallization inhibitor. The corneal stromal cells were seeded on sterilized composite membranes. After 5 h, the adhesion rate of stromal cells was more than 90%, cell could proliferate regularly on the composite membrane. There was no obvious difference in contrast to control plate. These results demonstrated that the composite membrane could promote corneal stromal cell proliferation.

Abstract: When aircrafts have hypersonic flights in the atmosphere, high-temperature IR windows become the main factor of complicated aero-thermo-radiation effects, which reduce the performance of IR detection systems, or even make these detection systems fail. Consequently, measuring thermo-radiation characteristics of IR window material is essential for the assessment of aero-thermo-radiation effect. By analyzing thermal radiation transfer in IR windows, a method is proposed to measure thermo-radiation characteristics of IR window materials, and an experimental platform is established. Based on the platform, thermo-radiation characteristics of a sapphire IR window of a MWIR detection system in a hypersonic vehicle are measured. The results indicate that, the thermo-radiation characteristics of the sapphire IR window material in 3.7μm-4.8μm have an approximate cubic relationship with temperature at 100~350. With the rise of temperature, the transmittance of the sapphire material decreases, while the self-radiation increases. Subsequently, the self-radiation can drive detector into saturation easily, of which the influence on the MWIR detection system is bigger than that of the transmittance. And, with thickness increasing, transmittance decreases exponentially, and self-radiation increases, but the increment decreases exponentially. Consequently, as IR windows’ thickness or temperature increases, SNR of the MWIR detection system declines, saturation of IR detectors occurs easily.

Abstract: The stability of the fluorine doped tin oxide (FTO) and the indium doped tin oxide (ITO) films, which are used as gene chip carrier, are detected in an acid solution. The change of relative resistivity (Δ R/R) with immersion time and average visible light transmittance of the films are contrasted before and after immersing in 1 mol/L (1M) H₂SO₄ solution. The results indicate that the Δ R/R of ITO film sample increases rapidly with increasing the immersion time, and Δ R/R is 111% after 12 h;However, the Δ R/R of FTO film sample increases smoothly and the Δ R/R is 2.9% after 100 h immersion. At the same time, the average visible light transmittance of FTO film decreased, but ITO film is completely corroded, and the average visible light transmittance is close to the glass transmittance. The potentiodynamic polarization curves show that the corrosion current of FTO film is 1.749 × 10⁻⁶A and less than ITO,so the corrosion resistance of FTO film is higher than ITO film in 1M H₂SO₄ solution. Moreover, the corrosion morphology validates this conclusion.

Abstract: We designed MoS₂/SiO₂ one-dimensional (1D) photonic crystal using the concept of photonic crystal and investigated the light transfer properties by means of transfer-matrix method. We found that the transfer properties of photonic crystal can be modified by the period of photonic crystal, the thickness of dielectric layer, and the number of the defect layers. The number of photonic band gaps (PBGs) reduces with the decrease of the thickness of dielectric layer, and the position of PBGs in the spectra rapidly moves to short wavelength direction. For defect photonic crystal, the width of the PBGs obviously become larger, and the transmittance spectra oscillate more intensely, similar to the characteristics of Bragg gratings. These properties will give good instructor for the preparation of 1D MoS₂ quantum well light emitting devices and solar cells.