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引言溴氧化镧:铽荧光粉是一种高效率的X线发光材料,Blasse[1]等首先报导了这类发光材料。可能由于制成品的化学组成偏离或结晶不好,以致当时所测得的发光效率极低。1971年,据美国通用电气公司Rabatin报导,他们制得了高效率X线发光荧光粉LaOBr:Tb(Ce)和GdOBr:Tb(Ce)[2],并制成了X线像变换器[3]。这种发光材料的发光效率很高,引起了人们的注意。随后Rabatin发表了一系列有关的研究报告[4-8]。北京大学等单位也于1977年先后试制了上述发光材料[9]。溴氧化镧:铽荧光粉的发光效率约为20%[10],大约是通常所用钨酸钙荧光粉的4～6倍,对X线的吸收效率比钨酸钙增加50%以上,同时,兰色发光的辐射量增大3～4倍[12]。目前,
Introduction Lanthanum oxybromide: Terbium phosphor is a highly efficient X-ray luminescent material, Blasse [1] et al. First reported such luminescent materials. May be due to the chemical composition of the finished product deviation or poor crystallization, so measured luminous efficiency was very low. In 1971, according to Rabatin, the United States General Electric Company, they fabricated high-efficiency X-ray luminescent LaOBr: Tb (Ce) and GdOBr: Tb (Ce) [2] . The luminous efficiency of this luminescent material is high, aroused people’s attention. Subsequently Rabatin published a series of related research reports [4-8]. Peking University and other units also trial-produced in 1977 the above luminous materials [9]. Lanthanum Bromide: Luminescent efficiency of terbium phosphor is about 20% [10], which is about 4 to 6 times that of commonly used calcium tungstate phosphors, and the X-ray absorption efficiency is increased by 50% or more than calcium tungstate. Meanwhile, The amount of blue glow increases 3 to 4 times [12]. Currently,