An electrical connector includes a dielectric housing with a plurality of filtering modules therein. The first internal electrode portion is provided on a first through-hole portion, one end of the first internal electrode portion being connected to the first external electrode layer. The main body controller changes a read region in an X-ray detector with respect to the x-axis direction in a detection surface of the X-ray detector during the X-ray CT photography. In some examples, the therapy is stimulation therapy. The resistive etching solution allows for fast and effective etching of a nickel-chromium alloy in cases where the ratio of copper surface area to nickelchromium surface area, is relatively large, and where fine feature etching is desired. One end of the wave-guide terminates at the front facet and the other end terminates proximate, but not necessarily at, the back facet.