To provide a green-emitting phosphor the excitation source of which is a mercury bright line and which efficiently absorbs the mercury bright line and emits green light with short afterglow; and a mercury fluorescent lamp using the same.
The green-emitting phosphor contains calcium, magnesium, silicon, and oxygen, contains europium as an activator, and is represented by the formula: Ca3(1-x)Mg3Si4O28:Eux (wherein 0.005≤x≤0.5). The phosphor efficiently absorbs ultraviolet light at wavelengths of about 277 nm and 380 nm and emits green light having an emission peak at a wavelength of 530 nm and a short afterglow time. Since the phosphor efficiently absorbs ultraviolet light at near a wavelength of 380 nm, which is in the light emission region of an ultraviolet light-emitting diode, the phosphor can be used for a light-emitting diode which has a structure emitting light by a phosphor using the ultraviolet light-emitting diode as the excitation source.
YOSHIDA HISAFUMI
Kawai Nobuaki
Yasuhisa Tanizawa