Document Type and Number:
Japanese Patent JPS5627863
Kind Code:
B2
Application Number:
JP9530272A
Publication Date:
June 27, 1981
Filing Date:
September 22, 1972
Export Citation:
International Classes:
G03B31/00; G03B23/06; G03B31/04; G11B31/00; (IPC1-7): G03B31/04; G11B31/00