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With the advent of artificial intelligence and unmanned driving, it is an inevitable trend to provide laser‐driven adaptive lighting with super‐brightness, high penetration, and high spatial resolution; one of the best solutions is to pump pixelated phosphor converters by laser diodes (LDs). However, achieving high‐performance pixelated phosphor converters remains a great challenge due to the large size of commercial phosphor particles. In this study, promising pixelated phosphor films are proposed to be fabricated by producing arrayed holes in the Ag substrate with the laser direct writing technology and then filling the holes with the mixture of phosphor particles and the heat‐resisting inorganic glue. A strong thermal transfer field grid is built in Y3Al5O12:Ce3+‐pixelated‐film@Ag, which can withstand a high luminance saturation threshold of over 18.08 W mm−2 pumped by blue LDs. The maximum luminous flux density is ≈1300 lm mm−2, and the luminance is 3.36 × 107 cd m−2 of the white pixel light with excellent uniformity. Further, based on this fabrication strategy, the full‐color‐pixelated‐film@Ag is successfully prepared for the first time. The realization of laser‐driven white pixel light and full‐color pixel light shows an interesting application in intelligent adaptive lighting, and this study paves an avenue for designing pixelated phosphor converters. [ABSTRACT FROM AUTHOR]

Experimental investigations on the flow boiling heat transfer characteristics of high-pressure water are carried out in parallel twin narrow rectangular channels. An integrated structure was utilized to define the geometry of the test section in this study. The cross-sectional size of a single channel measures 60 × 2 mm, with an effective heating and flow length of 1450 mm. Experiments encompass a range of pressures 10–16 MPa, mass flux 500–1500 kg m−2·s−1 and heat flux 100–300 kW m−2. First, the heat transfer characteristics in the parallel twin channels are determined. Results show the heat transfer and flow distribution between the twin channels are generally balanced, with only a slight fluctuation observed near the saturation point. Besides, for one narrow rectangular channel, the boiling heat transfer coefficient is found to be essentially affected by the system parameters. The increases in mass flux, heat flux, and pressure will all exert the promotion of boiling enhancement. Among these factors, pressure and heat flux have a relatively more pronounced impact. In addition, heat transfer mechanisms in narrow rectangular channel with a large aspect ratio under high-pressure conditions are analyzed in detail. The transverse buoyancy effect has been identified as a significant factor in the regions of single-phase forced convection and partial subcooled boiling. Once the heat transfer reaches the stage dominated by nucleate boiling, the bubble nucleation and motion behaviors constitute the primary factors of heat transfer enhancement, under the coupling effects of channel structure and high-pressure conditions. • Boiling heat transfer in parallel twin narrow rectangular channels is investigated. • Developed test section geometry is designed and applied to this study. • Buoyancy effect was observed in transverse direction of the channel. • High pressure improved the heat transfer performance in narrow rectangular channel. [ABSTRACT FROM AUTHOR]