Kenzaburo Iijima

Electric stringed musical instrument equipped with detector optically detecting string vibrations

An electric guitar has a plurality of strings stretched over a rigid body and a neck, and a vibration detecting unit embedded into the rigid body, and the vibration detecting unit has a plurality of photo emitting elements paired with a plurality of photo detecting elements spaced apart from the associated photo emitting diodes in directions parallel to the associated strings, wherein the photo emitting elements radiate light spots toward the associated strings for causing the reflections to be fallen upon the associated photo detecting elements so that the photo detecting elements produces photo currents without any diffraction of light.

Multilayer magnetic head core

In a metal-insulator alternate type multilayer head core usable for magnetic sound recording and reproducing, metallic component layers are connected to each other via one or more metallic interconnecting layers passing locally through insulating component layers in order to provide high effective permeability with minimized eddy current loss. In manufacturing, a metal-insulator alternate type multilayer construction including the metallic interconnecting layer or layers is subjected to sintering in order to avoid intermetal separation to be otherwise caused by cracking in the insulating layers.