Patent · US Expired

Image mask for microfiche

US4688911A · kind A · utility

6Cited by
4References
5Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJul 31, 1986
Grant dateAug 25, 1987
Priority date
Expiry dateJul 31, 2006

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03B21/115
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

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.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.