摘要： As mentioned in the previous chapters, demands for various EM-wave absorbers are rapidly increasing along with the trends toward complicated electromagnetic environments and the development of higher frequency communication equipment. Generally, it has been considered highly difficult to produce new EM-wave absorbers having a desired absorbing frequency and an absorbing characteristic. One reason for this is that realizing an optimum material constant satisfying the required characteristics becomes difficult when manufacturing an EM-wave absorber. That is, in the conventional method, it often becomes difficult to freely control parameters such as the mixing ratio of the EM-wave absorber’s raw materials, the firing temperature, the pressure, and the material compositions to realize the appropriate absorber. Furthermore, the problems of accurately measuring material constants and maintaining the accuracy of component sizes become important to the EM-wave absorber in high-frequency use, particularly in the millimeter or terahertz band.