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Top-emitting organic light-emitting diodes can achieve high efficiencies due to the strong cavity effect resulting from the relatively thick semi-transparent metallic top electrode. The strong cavity resonance, however, simultaneously brings along negative side effects such as pronounced angular-dependent emission and spectral narrowing. In this work, through numerical simulations, we demonstrate that top-emitting organic light-emitting diodes using a thin Au(2 nm)/Ag(7 nm) top electrode can achieve light-outcoupling efficiency comparable to a thick silver electrode, while reducing spectral narrowing. This can be realized by tuning the organic capping layer thickness without affecting the electrical properties, which can be applied to diodes based on either intrinsic or efficiently doped charge transport layers.

Semi-transparent surfaces for cutoff of the fields in the shadow domain of an antenna are considered. For relatively large screen sizes, the analytical synthesis procedure of the grid impedance is formulated in the approximation of geometric optics (GO), which provides a purely real impedance. For smaller sizes, a numerical procedure to synthesize realizable complex impedance has been implemented. A prototype of the compact antenna system with lossy semi-transparent impedance surface has been developed. No noticeable degradation of the antenna gain in the open space domain has been detected. Perspectives for further reduction in the screen size by employment of a dual-current layer are discussed; estimates of the serial impedance of the magnetic portion are provided.

The BiSPVT system involves an integration of semi-transparent photovoltaic (SPV) modules with buildings along with the provision of harvesting thermal energy. The system generates electrical and thermal energy for the building as well as provides day-lighting. However, during summer season the production of thermal energy is higher and thermal demand is lesser as compared to winter season. Also, the higher thermal energy production is unfavourable for the generation of electrical energy by SPV modules. The use of movable insulation (MI) on glazed wall can be one of the method to reduce the thermal energy generation. In this paper, a thermal model has been developed for BiSPVT system and the effect of MI on thermal performance of the system is studied. The energy balance equations are obtained for the inclined SPV modules (top), reinforced cement concrete (RCC) floor (bottom), air of room (SPV modules, floor and four brick/glazed side walls). The room temperature and SPV cell temperature are derived as a function of a) climatic parameters (solar irradiance and ambient temperature), b) design parameters and c) heat transfer coefficients by using the energy balance equations. It is found that by using MI with less or no air cavity thickness, the temperature of room has reduced by 1.93°C. However, the effect of MI on SPV cell temperature is marginal. The proposed model can be utilized to evaluate cell and room temperatures for BiSPVT system installed at different places of the world provided solar irradiance and ambient temperature of that place are known.

The study of the radiation patterns of laser-generated longitudinal ultrasound in semi-transparent solid is presented. The experimental results are in good agreement with the theory based on the effect of optical penetration within the sample.

Broad tunability of the infrared free electron laser will open a new scheme of material removal from solid target. In the mid infrared wavelength region, there are various materials with variety of the optical absorption coefficient. In the FEL ablation process, Si micro drilling with smaller diameter and increased depth would be realized. The micro drilling experiments of various semi-transparent materials will be discussed relating with the volume absorption effect.

This work examines the effects of anisotropy and transparency on measurements of thermal diffusivity components with an ac calorimetric method associated with laser heating. Analytical results indicate that the region where the two-dimensional effect occurs increases with the decrease of the ratio of cross-plane to in-plane thermal diffusivity. The region also increases with the optical thickness of the sample. The linear relations, as indicated by a decay constant from which the cross-plane thermal diffusivity is deduced, are not obtained for media of both optically moderate and thin thickness, while at sufficiently large optical thickness, anisotropy and two-dimensional effects are found insignificant.

The imagery by an objective with a central semitransparent obstruction has been studied. As noticed by earlier workers who have investigated the blocked filter, a dark line appears in the location of the geometrical image of the edge. The linewidth measurement is made using this fact. The optimum filter diameter to minimize the error is calculated as a function of the transmittance. Due to the non-blocked filter effect, the far-field holography recording of small opaque objects is possible with an important depth of field.