We proposed a new full-color display framework QD-OLEDs, where blue OLEDs are used as pump light, and red and green QDs are printed on color filters as color conversion layers.

Perovskite materials have attracted great attention as a potential color conversion material in the display field recently. However, preparing a large and thick patterned film remains to be a key challenge. Here, a patterned CsPbBr3 quantum dot color conversion layer is prepared using the inkjet‐printing and UV‐curing method. The prepared 6 µm film exhibits a uniform morphology without coffee‐ring effect. Green emission is achieved with a brightness of 58 cd m−2 and narrow emission band is achieved using the 345 cd m−2 blue OLED excitation light. Furthermore, only 1.4% of decay in brightness is observed after the film is exposed to ambient environment for 1 month without any protection. Finally, a 6.6 in. active matrix perovskite quantum dot display prototype is demonstrated using the blue OLED backlight with 384 × 300 resolution for the first time.

toward stability are yet needed since the lifetime of the reported devices is too short for consumer applications.Besides the application in LEDs, perovskite materials have also been adopted as downconverters in the backlight for liquid crystal displays (LCDs). [9][10][11] In 2016, Zhou et al. demonstrated stable green emissive films composed of MAPbBr 3 nanocrystals embedded polymer matrix through an in situ process. [10] Color gamut of 121% National Television Standards Committee was achieved by integrating these perovskite polymer composite films and red emissive phosphor with blue InGaN chips. In the same year, Wang et al. realized comparable results through swelling-deswelling microencapsulation strategy. [11] Both of the aforementioned films are proved to be ultrastable even in ambient atmosphere, which manifest considerate possibilities for their future commercialization. In 2018, Naijun et al. successfully applied perovskite films into an LCD prototype for the first time. [9] In backlight applications, the photonic energy conversion of short-wavelength light sources is generally incomplete, therefore, incorporation of color filters is inevitable. However, when it comes to the incorporation of suitable materials as color-conversion layers (CCLs) for visible blue light to achieve full color display, complete photoconversion should be enabled. Perovskite materials originally possess the potential to be utilized as CCLs for visible blue light due to their rather high photoluminescence quantum yields (PLQYs) and bright vivid colors. [12][13][14] Nevertheless, there is still no demonstration of perovskite materials for CCL applications. The pivotal requirement for CCLs is to realize complete energy conversion from short-wavelength light sources (such as: blue light). However, if the CCL is not thick enough, a portion of back light will remain unconverted thereby resulting in incomplete photoconversion. Currently, spin casting is the most widely adopted method to fabricate perovskite films while it is only suitable for nanometerthick films which are not adequately thick to be employed as CCLs. Therefore, a key challenge for perovskite materials to apply them as CCLs is to obtain films with higher thickness. Solvent annealing [15,16] or gas-solid [17] methods have been used to fabricate over one micrometer-thick perovskite films, however, they are still not sufficiently thick for efficient photoconversion. Metal halide perovskite materials have attracted great attention owing to their fascinating optoelectronic characteristics and low cost fabrication via facile solution processing. One of the potential applications of these materials is to employ them as color-conversion layers (CCLs) for visible blue lightto achieve full-color displays. However, obtaining thick perovskite films to realize complete color conversion is a key challenge. Here, the fabrication of micrometer-level thick CsPbBr 3 perovskite films is presented through a facile vacuum drying approach. An efficient green photoconversion is realized in a ...

The large-signal modulation characteristics of a GaN-based micro-LED have been studied for Gbps visible-light communication. With an increasing signal modulation depth the modulation bandwidth decreases, which matches up with the increase in the sum of the signal rise time and fall time. By simulating the band diagram and the carrier recombination rate of the micro-LED under large-signal modulation, carrier recombination and the carrier sweep-out effect are analyzed and found to be the dominant mechanisms behind the variation of modulation bandwidth. These results give further insight into improving the modulation bandwidth for high-speed visible-light communication.

The electrical characteristics of the BCE-structure IGZO TFTs were studied. Through modifying the passivation layer and optimizing the selection of copper acid and PFA material, the TFTs exhibited good threshold voltage and reliability. Finally, a high performance 31-inch 8K4K GOA LCD was demonstrated.