Luminescent material
AssigneeKabushiki Kaisha Toshiba
InventorsMasahiro Kato, Yumi Fukuda, Naotoshi Matsuda
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Abstract
According to one embodiment, the luminescent material emits light with an emission peak within a wavelength range of 490 to 580 nm when excited with light having a wavelength range of 250 to 500 nm and includes a particle containing a Sr3Si13Al3O2N21-based crystal activated by Eu. The particle includes an outer region which is within a depth of 5 nm from a surface of the particle and an inner region which is deeper than the outer region. The outer region and the inner region satisfy a ratio Oouter/Oinner of 1.0 to 3.8. Oouter is an average of oxygen concentration in the outer region and Oinner is an average of oxygen concentration in the inner region.
Claims20
A luminescent material which emits light having an emission peak within a wavelength range of 490 to 580 nm when excited with light having a wavelength range of 250 to 500 nm, the luminescent material comprising:
- a particle comprising a Sr3Si13Al3O2N21-based crystal activated by Eu and comprising an outer region which is within a depth of 5 nm from a surface of the particle and an inner region which is deeper than the outer region, the outer region having an average oxygen concentration Oouter greater than an average oxygen concentration Oinner of the inner region and satisfying a ration Oouter/Oinner of 1.0 to 3.8.
Dependencies are inferred from the claim text.