Phosphors for Radiation Detectors

10New Materials for Radiation Detectors: Transparent Ceramics

Takumi Kato, Noriaki Kawaguchi, and Takayuki Yanagida

Nara Institute of Science and Technology, Ikoma, Japan

10.1 Introduction of Transparent Ceramic Materials

10.1.1 Light Scattering Sources in Ceramics

First of all, the words of “Translucent” and “Transparent” are defined. Translucent and Transparent mean light transmittance evaluated by in‐line and total light transmittance, respectively. Figure 10.1 is a schematic diagram of measurement methods for in‐line and total light transmittance. But, conventionally, ceramics with high transparency are often called “Transparent” ceramics, and those with low transparency are called “Translucent” ceramics.

Figure 10.1 Schematic diagrams of measurement methods for (a) in‐line and (b) total light transmittance.

In general, UV–Vis light cannot be transmitted in ceramics. The reason is that the inside of the material can include light scattering sources. These can include pores and secondary phases due to impurities at the grain boundary, causing scattering sources characteristic of ceramics. In addition, roughness on the surface and macro defects contribute to light loss. These light scattering sources are depicted in Figure 10.2.

Figure 10.2 Light scattering sources in ...