Document Type and Number:
Japanese Patent JPS53164135
Kind Code:
U
Application Number:
JP6957677U
Publication Date:
December 22, 1978
Filing Date:
May 30, 1977
Export Citation:
International Classes:
G03B21/00; G03B31/00; G03D15/00; (IPC1-7): G03B21/00; G03B31/00