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新型闪烁晶体的研究是各国在材料领域的一项重要内容。钨酸盐系列闪烁晶体，如钨酸锌、钨酸钙和钨酸镉晶体，具有一系列独特的优点。钨酸铅（ＰｂＷＯ４）晶体是新发现的闪烁晶体，该晶体具有高密度（８．３ｇ／ｃｍ３）、快的衰减时间（小于３０ｎｓ）和晶体易于生长等性能，被欧洲核子中心正在建造的强子对撞机（ＬＨＣ）上的ＣＭＳ实验正式选为探测器材料。ＰｂＷＯ４晶体还将在其它高能物理、天体物理、强辐射高剂量的辐射测量等方面作为一种非常有价值的闪烁探测器材料而有较广泛的应用前景。不同于早先发现的钨酸盐系列闪烁晶体，钨酸铅晶体存在着位于蓝光和绿光波长的快成分输出。目前，对于钨酸铅晶体的发光机制的研究进行很多，但还没有获得明确的结论。种种实验现象表明，晶体的发光与晶体的结构缺陷因素有关，本实验对这方面的因素进行了研究。在钨酸铅晶体中，如果存在４２０ｎｍ的吸收，会导致晶体的快成分光输出降低，因为４２０ｎｍ的吸收会导致晶体对蓝光快成分的自吸收。实验证明，该吸收峰与晶体中某些三价阳离子杂质有关，特别是与过渡元素的三价离子如Ｆｅ３＋有关。采用真空退火的方法可以消除４２０ｎｍ的吸收峰，使晶体的光输出得以提高，但这种提高会导致晶体的抗辐照性能变差?
The study of new scintillation crystals is an important part of the material field in various countries. Tungstate series scintillation crystals, such as zinc tungstate, calcium tungstate and cadmium tungstate crystals, offer a unique set of benefits. Lead tungstate (PbWO4) crystal is a newly discovered scintillation crystal with high density (8.3g / cm3), fast decay time (less than 30ns) and crystal growth and other properties are being built by the European Nuclear Center The CMS experiment on the LHC was officially selected as the detector material. PbWO4 crystals will also have a wide range of applications as a valuable scintillation detector in other high-energy physics, astrophysics, high-radiation and high-dose radiation measurements. Unlike previously discovered tungstate series scintillation crystals, lead tungstate crystals have fast component outputs at blue and green wavelengths. At present, there are many researches on the light-emitting mechanism of lead tungstate crystals, but no clear conclusion has been reached yet. Various experimental phenomena show that the crystal luminescence and structural defects of the crystal factors, the experimental study of these factors. In the lead tungstate crystals, if there is absorption at 420 nm, the fast component light output of the crystal will be reduced because the absorption at 420 nm will lead to self-absorption of the fast blue component by the crystal. Experiments show that the absorption peak is related to some trivalent cation impurities in the crystal, especially with the trivalent ions of transition elements such as Fe3 +. The vacuum annealing method can eliminate the absorption peak of 420nm, the crystal light output can be improved, but this increase will lead to deterioration of the crystal anti-radiation performance?