Luminescence Characteristics Of Blue Phosphor And Fabrication Of A Uv-Based White Led

We have synthesized a CaMgSi2O6:Eu2+ blue phosphor via a solid-state reaction method. The CaMgSi2O6: Eu2+:Eu2+ phosphor has monoclinic structure with a space group of C2/c (15), and an emission band peaking at 450 nm (blue) due to the 4f(7)-4f(6)5d transition of the Eu2+ ion. The emission intensity at 100 degrees is 54% of the value at room temperature. A white LED was fabricated by integrating a UV LED (400 nm) with our blue phosphor plus two commercial green and red phosphors. The white LED shows a color temperature of 3500 K with a color rendering index of 87 (x = 0.3936, y = 0.3605), and a luminous efficiency of 18 lm/W. The white LED shows a luminance maintenance of 97% after operation at 350 mA for 400 hours at 85 degrees C.