Document Type and Number:
Japanese Patent JPS4990123
Kind Code:
A
Application Number:
JP284373A
Publication Date:
August 28, 1974
Filing Date:
December 26, 1972
Export Citation:
International Classes:
G03B17/18
Domestic Patent References:
| JPS4214356Y1 | 1967-08-16 | |||
| JPS4964426A | 1974-06-21 |