Patent US 4,179,743

An automatic microfilm retrieval system for retrieving contents of a dictionary or the like recorded on a microfilm and displaying them on a screen is disclosed. Said microfilm includes a retrieval cord and divided into a plurality of unit regions to be displayed on said screen at the same time and further includes a cord added to each of said unit regions and representing an index word whose contents are included in each of said unit regions. A plurality of said unit regions are assembled into a plurality of groups. To each of said groups are added cords representing first and last index words included in each of said groups. Provision is made of a subtracter which functions to compare said cords read out by a reading head with key inputs obtained by depressing keys provided on a key board and control movements of a movable stage holding said microfilm thereon, thereby retrieving said microfilm.