Abstract
As is generally known, by detecting a variation in high-frequency loss of material with a high- sensitivity measuring instrument, quality of the material is continuously checked and thus manufacturingprocesses can be controlled. Needless to say, a measuring instrument to be used for this purpose must beinsensitive to any reactance change in the material and stable for long hours continuous operation. Twotypes of meters introduced herein as trail products have a sensitivity of 10 to 30 μA per 10 MΩ to highfrequencyloss, while their sensitivity to capacity variation is less than 1 to 3 μA per 10 pF. Both of thesemeters are most fit for analyzing every kind of material as well as for measuring the thickness of materialand the density of solution. In their application to the measurement of tin and aluminum foils, it wasproved that they successfully detect any deviation in the thickness up to 0.1μ.
