1960 年 16 巻 4 号 p. 286-288
In the ordinary pitch indicator it is impossible to find in the melodic curve the exact location corresponding to each spoken syllable. An improvement in this respect is achieved by the new pitch indicator which combines pitch and zero-crossing interval indications. The relation between voiced and voiceless, and the transition of tone quality are indicated by this combination. In this system, the indications of both quantities are continuous and inertialess, and if undesired noises are sufficiently suppressed, very weak signals can be distinctly traced. This system may be regarded as a special type of visible speech which is the complement of the sound spectrograph to be applied therewith.