Infrared light-excited light-emitting substance

Abstract

An infrared light-excited light-emitting substance given by the general formula: R1.sub.x R2(.sub.1-x)Ba.sub.z Cl.sub.3+2z where R1 is a rare-earth element, x satisfies the relation 0.01<x.ltoreq.1, R2 is another rare-earth element, and z satisfies the relation 1<z<4. Preferably, the substance is a transparent crystal having a transparency exceeding 70% in a wavelength range from 400 to 1500 nm, excluding wavelengths absorbed by rare-earth ions. The light-emitting substance can convert infrared light into visible light in a wavelength range from blue light to green light at a high conversion efficiency.

Dependencies are inferred from the claim text.