Document Type and Number:
Japanese Patent JPS49111627
Kind Code:
A
Application Number:
JP2145773A
Publication Date:
October 24, 1974
Filing Date:
February 22, 1973
Export Citation:
International Classes:
G03B31/04
Domestic Patent References:
| JP40016832A |
Foreign References:
| US3462213A | 1969-08-19 | |||
| US3138796A | 1964-06-23 | |||
| US2637023A | 1953-04-28 |