Hill, Van Santen, Steadman & Simpson
Diaphragm
 A diaphragm using a metal material applied with anodic oxide films, in which said metal material contains one of lead compounds, inorganic metal compounds and phosphor compounds at least to a portion in the micropores of the anodic oxide film. 
Sony Corporation and Fujikura Ltd.
H H Y H H
H04R H04R Y10T H04R H04R
additional additional additional inventional inventional
Masana Nobuo Shinichi Hiroyuki Koichi Masatsugu
Ugaji Fuke Watanabe Sogawa Saruwatari Maejima