Document Type and Number:
Japanese Patent JPS50145136
Kind Code:
A
Application Number:
JP5199074A
Publication Date:
November 21, 1975
Filing Date:
May 10, 1974
Export Citation:
International Classes:
G03B31/00; (IPC1-7): G03B7/00
Domestic Patent References:
| JP37005539A | ||||
| JPS434407Y1 | 1968-02-26 |
Foreign References:
| US3771864A | 1973-11-13 | |||
| DE1937730A1 | 1970-02-26 |