Document Type and Number:
Japanese Patent JPS5628255
Kind Code:
B2
Application Number:
JP1886573A
Publication Date:
June 30, 1981
Filing Date:
February 15, 1973
Export Citation:
International Classes:
G03B19/18; G03B17/26; G03B17/50; G03B21/00; G03B21/10; G03B23/02; G03D9/02