Development of a high quantum efficiency photo multiplier tube

对高量子效率光电倍增管（PM管）的需求近年来，在闪烁计数器辐射测量、荧光分析、光子计数测量等领域中，光电阴极的应用越来越广泛，提高光电阴极质量的方法之一是利用穿过光电阴极的光，并将其应用到光电阴极的测量中。而不产生光电子。我们有一个新的想法，使用二次PC和反射器，利用穿透光。为了检验这种想法的效率，我们测量了波长在250 nm和700 nm之间的透射率、反射率、吸收率和量子效率。P.C.in在400 nm处获得的数据如下：从这个结果来看，预期使用次级P. C.和反射器可使Q. E.提高15%-30%。结果表明，二次相位校正和反射器对提高Q. E.是有效的。还发现Q.E.取决于P.C.的厚度，为了优化二次PC和反射器的效果，还需要进一步研究。

Demands for a photo multiplier tube (PM tube) with a high quantum efficiency (Q.E.) are recently increasing in many fields such as the radiation measurement with scintillation counters, the fluorometric analysis, the photon counting measurement, and so on. One of the ways to improve of the Q.E.of a PM tube is to utilize the light which penetrates the photo cathode (P.C.) without producing photo electrons. We have a new idea of using the secondary P.C.and the reflector to make use of the penetrating light. In order to check the efficiencies of this idea, we measured the penetrability, the reflectance, the absorption ratio and the quantum efficiency of the P.C.in the range of the wave length between 250nm and 700nm. The data obtained at 400nm are as follows ;From this result, an improvement of the Q.E.with a factor of 15%-30% is expected with the use of the secondary P.C.and the reflector. It indicates that the secondary P.C.and the reflector are effective for the improvement of the Q.E.. It was also found that the Q.E.depends on the thickness of the P.C., and it should be studied further in order to optimize the effect of the secondary P.C.and the reflector.