• Journal of the Korean Ceramic Society
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• v.43 no.3 s.286
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• pp.169-172
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• 2006

We have synthesized a $Eu^{2+}-activated\;{(Sr,Ba)}_2SiO_4$ yellow phosphor and investigated the development of blue LEDs by combining the phosphor with a InGaN blue LED chip (${\lambda}_{em}$=405 nm). The InGaN-based ${(Sr,Ba)}_2SiO_{4}:Eu$ LED lamp shows two bands at 405 nm and 550 nm. The 405 nm emission band is due to a radiative recombination from a InGaN active layer. This 405 nm emission was used as an optical transition of the ${(Sr,Ba)}_2SiO_{4}:Eu$ phosphor. The 550 nm emission band is ascribed to a radiative recombination of $Eu^{2+}$ impurity ions in the ${(Sr,Ba)}_2SiO_4$ host matrix. In the preparation of UV Yellow LED Lamp with ${(Sr,Ba)}_2SiO_{4}:Eu$ yellow phosphor, the highest luminescence efficiency was obtained at the epoxy-to-yellow phosphor ratio of 1:0.45. At this ratio, the CIE chromaticity was x=0.4097 and y=0.5488.

• Journal of the Korean Ceramic Society
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• v.43 no.5 s.288
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• pp.304-308
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• 2006

We have synthesized a $Eu^{2+}-activated\;Sr_3MgSi_2O_8$ blue phosphor and $(Sr,Ba)_2SiO_4$ yellow phosphor and prepared white LEDs by combining these phosphors with a InGaN UV LED chip. Three distinct emission bands from the InGaN-based LED and the two phosphors are clearly observed at 405 nm, 460 nm and at around 560 nm, respectively. The 405 nm emission band is due to a radiative recombination from a InGaN active layer. This blue emission was used as an optical transition of the $Sr_3MgSi_2O_8:Eu$ blue phosphor and $(Sr,Ba)_2SiO_4:Eu$ yellow phosphor. The 460 nm and 560 nm emission band is ascribed to a radiative recombination of $Eu^{2+}$ impurity ions in the $Sr_3MgSi_2O_8:Eu$ and $(Sr,Ba)_2SiO_4$ host matrix. As a consequence of a preparation of UV White LED lamp using the $Sr_3MgSi_2O_8:Eu$ blue phosphor and $(Sr,Ba)_2SiO_4:Eu$ yellow phosphor, the highest luminescence efficiency was obtained at the ration of epoxy/two phosphor (1/0.2361). At this time, the CIE chromaticity was CIE x = 0.3140, CIE y = 0.3201 and CCT (6500 K).

• Journal of Applied Biological Chemistry
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• v.59 no.2
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• pp.95-98
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• 2016

Phototactic behavioral responses of the Indian meal moth, Plodia interpunctella ($H{\ddot{u}}bner$), adults were determined to different light-emitting diodes (LEDs) of seven wavelengths, and their behavioral responses were compared to that using a commercial luring lamp (BLB) under laboratory conditions. Based on the attractive responses under optimal light conditions (60 lx luminance intensity and 30 min light exposure time), the green LED ($520{\pm}5nm$) showed the highest attractive rate ($520{\pm}5nm$, 52.2 %), followed by the blue LED ($470{\pm}10nm$, 33.9 %), the yellow LED ($590{\pm}5nm$, 32.2 %), BLB (28.9 %), UV LED (365 nm, 22.8 %), the red LED ($625{\pm}10nm$, 14.5 %), the white LED (450-620 nm, 10.6 %), and IR LED (730 nm, 9.5 %). In addition, the green LED to P. interpunctella adults was approximately 1.81 times more attractive than BLB. These results indicate that the green LED could be most useful for monitoring of P. interpunctella adults.