We performed the simulation of white LEDs packaging with different chessboard structures of white light
converting phosphor layer covered on GaN die chip. Three different types of chessboard structures are called type 1,
type 2 and type 3, respectively. The result of investigation according to the phosphor thickness show the increasing
of thickness of phosphor layer are, the decreasing of output blue light power are. Meanwhile, the changes of yellow
light are neglect. Type 3 shows highest packaging efficiency of 74.3 % compares with packaging efficiency of type
2 and type 1 (72.5 % and 71.3 %, respectively). Type 3 also shows the most effect of forward light. Attention that
the type 3 chessboard structure gets packaging efficiency of 74.3 % at color temperature of daylight as well as high
saving of phosphor amount. The color temperatures of three types of chessboard structure are higher than 5000 K, so
they are suitable for lighting purpose. The angular correlate color temperature deviation (ACCTD) of type 1, type 2
and type 3 are 6500K, 11500K and 17000K, respectively.
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