FLUORESCENT SUBSTANCE, FLUORESCENT SUBSTANCE SHEET AND PROCESS FOR PRODUCING THE SAME, AND LUMINESCENT DEVICE USING SAID FLUORESCENT SUBSTANCE

摘要

This invention provides a fluorescent substance that exhibits a broad luminescence spectrum in a blue range (peak wavelength: 400 nm to 500 nm) and exhibits a broad and flat excitation band in a near-ultraviolet and ultraviolet range and possesses excellent luminescence efficiency and luminescence intensity/brightness. The fluorescent substance is represented by general formula MmAaBbOoNn:Z wherein M represents one or more elements which take a valence of II; A represents one or more elements which take a valence of III; B represents one or more elements which take a valence of IV; O represents oxygen; N represents nitrogen; Z represents one or more activators; and 5.0 < (a + b)/m < 9.0, 0 = a/m = 2.0, 0 = o < n, and n = 2/3m + a + 4/3b - 2/3o. The fluorescent substance is characterized in that, upon excitation with light in a wavelength range of 250 nm to 430 nm, the fluorescent substance exhibits a luminescence spectrum having a maximum peak wavelength range of 400 nm to 500 nm.