Most of the commercial white LED lamps use blue chip coated with yellow emitting phosphor. YAG:Ce3+ phosphor is coated on blue chip to obtain white light. Though this is commercially successful, there are several draw...Most of the commercial white LED lamps use blue chip coated with yellow emitting phosphor. YAG:Ce3+ phosphor is coated on blue chip to obtain white light. Though this is commercially successful, there are several drawbacks such as “halo effect”, poor colour rendition, etc. In recent years several efforts have been made to improve LED lamp performance. In this paper modifica-tion of YAG:Ce phosphor for improving CRI, by introducing Gd3+, Pr3+ or Tb3+ at Ce3+ site is reported.展开更多
In this paper we have reported green emission for europium activated strontium thiogallate. The phosphor is prepared by the precipitation method followed by heating at reducing atmosphere produced by the burning charc...In this paper we have reported green emission for europium activated strontium thiogallate. The phosphor is prepared by the precipitation method followed by heating at reducing atmosphere produced by the burning charcoal and characterized using XRD, PL and EL techniques. The phosphor SrGa2S4:Eu2+ gives intense green emission at 525 nm when excited by 400 nm wavelength. LEDs were also fabricated by coating europium activated strontium thiogallate on 390 nm LED chip. Intense green LEDs were obtained which can be useful for new LED applications. This phosphor can also be a prominent green component for the fabrication of white LEDs from UV diodes.展开更多
文摘Most of the commercial white LED lamps use blue chip coated with yellow emitting phosphor. YAG:Ce3+ phosphor is coated on blue chip to obtain white light. Though this is commercially successful, there are several drawbacks such as “halo effect”, poor colour rendition, etc. In recent years several efforts have been made to improve LED lamp performance. In this paper modifica-tion of YAG:Ce phosphor for improving CRI, by introducing Gd3+, Pr3+ or Tb3+ at Ce3+ site is reported.
文摘In this paper we have reported green emission for europium activated strontium thiogallate. The phosphor is prepared by the precipitation method followed by heating at reducing atmosphere produced by the burning charcoal and characterized using XRD, PL and EL techniques. The phosphor SrGa2S4:Eu2+ gives intense green emission at 525 nm when excited by 400 nm wavelength. LEDs were also fabricated by coating europium activated strontium thiogallate on 390 nm LED chip. Intense green LEDs were obtained which can be useful for new LED applications. This phosphor can also be a prominent green component for the fabrication of white LEDs from UV diodes.
