Document Type and Number:
Japanese Patent JPS631882
Kind Code:
Y2
Application Number:
JP20141483U
Publication Date:
January 18, 1988
Filing Date:
December 30, 1983
Export Citation:
International Classes:
G02B25/00; A47B23/00; A47B23/06; (IPC1-7): A47B23/00; G02B25/00