Laser-driven projection display puts forward urgent demand for color converter materials to achieve wide-color-gamut and high-quality image presentation. In this study, a hierarchical structure quantum dots-in-glass film (QiGF) is fabricated via co-sintering stable green/red-emitting CsPbX 3 @ glass (X 3 = Br 3 , Br 1.5 I 1.5 ) and commercial low-melting glass on the sapphire substrate. Benefiting from the well-retained optical properties of CsPbX 3 quantum dots in amorphous glass and high thermal conductivity, QiGF succeeded in inhibiting luminescence saturation after 20 W mm −2 blue laser irradiation. A brand-new white-lighting source designed by coupling a blue laser with a pattern "QiGF wheel" produced ultra-narrow blue/green/red tri-color emissions and total luminous flux of 146 lm. Accordingly, a QiGFconverted laser projection system is successfully designed for the first time, showing more natural and real color restoration for its wide color gamut display feature (157% of conventional light-emitting diode projection and 107% of NTSC standard). The present study highlights the practical application of CsPbX 3 quantum dots composite as an efficient laser-driven color converter in projection display.

In this letter, we report a novel microstrip interdigital hairpin resonator by having the parallel coupled lines in a conventional miniaturized hairpin resonator replaced by an interdigital capacitor. Equations are derived in order to design the resonator with an optimal physical length. It will be proved that the novel resonator can achieve even more size reduction than the conventional miniaturized hairpin resonator owing to the employment of the slow-wave structure. Finally, a four-pole cross-coupled bandpass filter using the optimal resonator is fabricated as verification.Index Terms-Bandpass filter (BPF), interdigital capacitor, microstrip, miniaturized hairpin resonator.

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Currently, advanced optical security techniques are imminent in response to the increasingly rampant counterfeit and pirated goods on a global scale. Herein, hexagonal Na(NdxY1−x)F4 (x = 0–1) solid‐solution nanocrystals (NCs) embedded glasses are successfully fabricated via in situ glass crystallization. Benefited from the protection of inorganic glass, Na(NdxY1−x)F4 NCs exhibit superior long‐term stability and can endure high‐power 808 nm laser irradiation. Importantly, opposite variations between near‐infrared (NIR) luminescence and laser‐induced temperature can be detected for the nanocomposites, which are sensitive to Nd3+ doping concentration. As a proof‐of‐concept experiment, Nd3+ concentration dependent anti‐counterfeiting patterns with high‐concealment and high‐precision are designed and show bright emission and dimmish thermal images in Nd3+‐tenuous composites under the irradiation of 808 nm laser, while opposite displays can be achieved in Nd3+‐enriched one. This kind of information encryption triggered by a commercial single light source to achieve dual opposing displays in one material can effectively improve security in anti‐counterfeiting.