RESUMO
Large-scale autostereoscopic three-dimensional (3D) light-emitting-diode (LED) displays can provide high-quality, even immersive, visual experiences. However, the unique structural characteristics of the LED display panel can enhance moiré effects during parallax generation. We present a novel method for quantitatively characterizing the moiré effect in autostereoscopic 3D-LED displays using a model applying geometrical ray tracing and a brightness distribution stack. An optical diffuser (OD) device for moiré reduction and performance balance is designed and the influence of several key device parameters on moiré pattern features are examined in autostereoscopic 3D-LED displays for the first time. Using the obtained optimal parameters, we assembled an ultra-large moiré-less autostereoscopic 3D-LED display prototype, which was experimentally shown to be capable of reducing moiré fringes without noticeable increase in crosstalk or significant reduction in visual quality. Finally, the effects on the moiré and crosstalk effect of altering key influencing factors were examined.
RESUMO
The low-cost large-scale fabrication of microlens arrays (MLAs) with precise alignment, great uniformity of focusing, and good converging performance are of great importance for integral imaging 3D display. In this work, a simple and effective method for large-scale polymer microlens arrays using screen printing has been successfully presented. The results show that the MLAs possess high-quality surface morphology and excellent optical performances. Furthermore, the microlens' shape and size, i.e., the diameter, the height, and the distance between two adjacent microlenses of the MLAs can be easily controlled by modifying the reflowing time and the size of open apertures of the screen. MLAs with the neighboring microlenses almost tangent can be achieved under suitable size of open apertures of the screen and reflowing time, which can remarkably reduce the color moiré patterns caused by the stray light between the blank areas of the MLAs in the integral imaging 3D display system, exhibiting much better reconstruction performance.
RESUMO
High-quality tetrapod-shaped Sn-doped ZnO (T-SZO) nanostructures have been successfully synthesized via the thermal evaporation of mixed Zn and Sn powder. The effects of the Sn dopant on the morphology, microstructure, optical, and field-emission (FE) properties of T-SZO were investigated. It was found that the growth direction of the legs of T-SZO is parallel to the [0001] crystal c-axis direction and that the incorporation of Sn in the ZnO matrix increases the aspect ratio of the tetrapods, leads to blue shift in the UV region, and considerably improves the FE performance. The results also show that tetrapod cathodes with around a 0.84 atom % Sn dosage have the best FE properties, with a turn-on field of 1.95 V/µm, a current density of 950 µA/cm2 at a field of 4.5 V/µm, and a field-enhancement factor as high as 9556.
