Oxide fluorescent material, light emitting device, and method for producing oxide fluorescent material

Abstract

An oxide fluorescent material comprises: at least one first element Mselected from Li, Na, K, Rb, and Cs; at least one second element Mselected from Mg, Ca, Sr, Ba, and Zn; at least one third element Mselected from B, Al, Ga, In, and rare earth elements; at least one fourth element Mselected from Si, Ti, Ge, Zr, Sn, Hf, and Pb; O; and Cr, wherein when the molar ratio of the at least one fourth element Min 1 mol of the composition is 5, the molar ratio of the at least one first element Mis 0.7 or more and 1.3 or less, the molar ratio of the at least one second element Mis 1.5 or more and 2.5 or less, the molar ratio of the at least one third element Mis 0.7 or more and 1.3 or less, the molar ratio of oxygen is 12.9 or more and 15.1 or less, and the molar ratio of Cr is more than 0 and 0.2 or less, and wherein the oxide fluorescent material has a light emission peak wavelength in a range of 700 nm or more and 1,050 nm or less in a light emission spectrum of the oxide fluorescent material.