In this work, we study the bistability of an active nonlinear microring resonator and design a flip-flop based on the active microring resonator. In the presence of nonlinear and linear loss, we use Er-doped gain medium in the microring to obtain gain to compensate for the loss of the resonator. Both analytical and numerical methods are used to solve the propagation in the microring with double couplers, and we obtain the hysteresis loops of the microring. The results obtained by the two methods reveal that, in the presence of nonlinearity in microring resonators, the system exhibits bistability, and the gain in the microring leads to a decrease of the bias power when the active microring is taken as a bistable switcher. Basing on the bistability of the microring, we realize a set-reset flip-flop by adding a positive or negative feedback onto the bias. We also find that the duration of the set and reset pulses must exceed the field buildup time of the microring if we want to achieve the switching of the bias signal. In our design, the duration time is about 2 ps.
Optical properties of dichroic dye‐doped nematic liquid crystal (N‐LC) cells with direct lamination reflective polarizer (DLRP) were studied. The dye‐doped N‐LC was switchable between transmitting and absorbing of the light passing through the DLRP. Electro‐optical performances with different cell gap were investigated. It was found that the transmittance decreased and the CR increased with increasing cell gap. When the cell gap was larger than a critical value, the bright transmittance of such cells could be higher than that of two cells with the same LC mixture due to the light enhancement of DLRP. In addition, the dark transmittance was nearly similar to that of double cells with different cell gap thanks to the inherent polarization of DLRP. The results showed that the dye‐doped N‐LC cell with DLRP has a good light tuning performance while thinner thickness of device.
With the development of the Internet of Things, transparent display is playing an increasingly important role in people's lives. The most important optical index of transparent display is transmittance. Due to no need for polarizer, transparent liquid crystal display (TLCD) with dichroic dye‐doped can achieve very high transmittance. In this paper, optical performance and image quality improvement of TLCD with dye‐doped liquid crystal were studied. A new TN pixel design with common electrode of ITO instead of metal to form stored capacitance was used to achieve high aperture ratio (AR). And it was found that bright transmittance of NWSC is higher than that of NBSC due to high anchoring effect of PI to positive liquid crystal. In addition, the transmittance decreases gradually with increasing cell gap due to the increased light absorption by the long axis of dye molecules. The results showed that the TLCD with Dichroic Dye‐doped Liquid Crystal (DDLC) has a good display effect.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.