1. Field of the Invention
The present embodiments relate to a green phosphor for a plasma display panel (PDP) and a PDP including a phosphor layer formed of the same, and more particularly, to a green phosphor for a PDP having an improved luminance saturation characteristic and a PDP including a phosphor layer formed of the green phosphor.
2. Description of the Related Art
Phosphors emit light when they are exposed to energy. In general, phosphors are used in light sources such as mercury fluorescent lamps and mercury free fluorescent lamps, electron emission devices, plasma display panels (PDPs), etc. In the future, phosphors may be used for a wider range of applications as new multimedia devices are developed.
PDPs are flat panel displays that display images using light emitted by ultraviolet rays that are created by discharge of a mixture of gases including neon and xenon injected into an area between a pair of glass substrates. Visible light is created by each phosphor using resonance radiation light of xenon ion (147 nm vacuum ultraviolet rays).
ZnSi2O4:Mn (ZSM) has been widely used as a green phosphor for PDPs, and ZSM has also been used as a main constituent of a green phosphor for PDPs in combination with YBO3:Tb (YBT) and (Ba,Sr,Mg)O.αAl2O3:Mn (BAM).
ZSM phosphors have excellent luminance, but short lifetime. Further, the surface of ZSM phosphors has a high negative polarity, thus resulting in a high discharge voltage. YBT phosphors have excellent luminance, long lifetime, and reduced discharge voltage, but poor color purity. BAM phosphors have excellent color purity and reduced discharge voltage, but short lifetime and long decay time.
ZSM phosphors can be used either alone or in combination with other phosphors to prepare a green phosphor layer for a PDP. Usually, ZSM is used alone, or as a main phosphor in combination with YBT and/or BAM. However, ZSM has luminance saturation. That is, luminance per unit sustain pulse is saturated as the number of sustain pulses increases, and a peak luminance which is a main property of PDPs decreases, and thus bright room contrast decreases.
Luminance saturation is an important factor determining gray-level and image quality. Thus, the development of a phosphor having long lifetime and excellent luminance without luminance saturation is urgently required.