A phosphor according to an embodiment is a europium-activated alkaline-earth chloroapatite phosphor having a composition expressed by a composition formula: (M.sub.1-xEu.sub.x).sub.5(PO.sub.4).sub.3Cl, where M is an alkaline-earth element containing at least Sr and Ba, x is an atomic ratio satisfying 0.04≤x≤0.2. In the phosphor of this embodiment, absorptance of light at a wavelength of 400 nm is 90% or more, and absorptance of light at a wavelength of 650 nm is 2% or less.

A phosphor according to an embodiment is a europium-activated alkaline-earth chloroapatite phosphor having a composition expressed by a composition formula: (M.sub.1-xEu.sub.x).sub.5(PO.sub.4).sub.3Cl, where M is an alkaline-earth element containing at least Sr and Ba, x is an atomic ratio satisfying 0.04x0.2. In the phosphor of this embodiment, absorptance of light at a wavelength of 400 nm is 90% or more, and absorptance of light at a wavelength of 650 nm is 2% or less.