发明名称 Image mask for microfiche
摘要 An image masking device for a microfilm reader and/or reader-printer is formed to slide longitudinally of a microfiche handler and comprises a thin opaque mask adapted to ride on the film handler adjacent a film to cover the film and define a clear line of demarcation between visible image portions and obscured portions.
申请公布号 US4688911(A) 申请公布日期 1987.08.25
申请号 US19860892244 申请日期 1986.07.31
申请人 MINNESOTA MINING AND MANUFACTURING COMPANY 发明人 SIMBAL, JOHN J.
分类号 G03B21/11;(IPC1-7):G03B21/14 主分类号 G03B21/11
代理机构 代理人
主权项
地址