Document Type and Number:
Japanese Patent JPS5215794
Kind Code:
Y2
Application Number:
JP11262372U
Publication Date:
April 09, 1977
Filing Date:
September 28, 1972
Export Citation:
International Classes:
G03B23/02; G03B21/64; G03B23/00; G11B23/44; (IPC1-7): G03B23/00