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Phosphor layers are of vital importance for the development of advanced phosphor-converted light-emitting diodes (LEDs). However, owing to the fixed ratio of red-green-blue (RGB) phosphors, it has been difficult for the RGB phosphor layers with conventional structure to tune light emission colours. Herein, we have experimentally fabricated nine types of phosphor layers with patterned RGB pixel array, which consist of tuneable RGB ratio in a planar configuration. Moreover, we carried out optical simulation based on Monte-Carlo theory to assist in adjusting the light-emission colours and the corresponding chromaticity coordinates. The simulations were further verified by the experimental results via samples fabricated by the stencil printing technique. In accordance with the nine types of phosphor layers with patterned pixel arrays in various RGB ratios, we have finally obtained corresponding nine light-emission colours for the applications of LED light emission decoration. These designed advanced pixel-array phosphor layers demonstrate great potential for applications in decorated light emission and display devices with significant implications for industrial improvement in these research areas. • Nine patterned phosphor layers can realize nine output light colours. • With increasing mixing time of RGB phosphors, more output light colours of phosphor layers can be obtained. • The pixel-array phosphor layers was prepared via stencil printing method which is suitable for a large-scale production. [ABSTRACT FROM AUTHOR]

Phosphor layer are essential in the application of phosphor-converted white light emitting diodes (pc-WLEDs). However, the conventional structure of red–green–blue (RGB) phosphor layers can cause severe re-absorption of blue light, resulting in low luminous efficiency and colour rendering index (CRI). In this paper, we fabricated a new WLEDs phosphor layer, which consisted of patterned RGB phosphor pixel arrays in a planar configuration, by the stencil printing technique. Optical simulation based on Monte-Carlo theory has been applied to assist designing the optimal pattern of the phosphor pixel arrays. By tuning the layout of the pixel arrays and the size of phosphor pixels, we achieved uniform output white light with high luminous intensity of 1.47 × 109 cd and CRI of 95.6, which are superior compared with the intensity of 1.11 × 109 cd and CRI of 93.5 obtained from WLEDs with conventional dispensing phosphor layer. Our newly-designed phosphor pixel-array layer possesses great potential for applications in advanced lighting and display devices with vast implications for industrial improvement in these research areas. [ABSTRACT FROM AUTHOR]