MICROFICHE

Microfiche

• It is compact, with far smaller storage costs than paper documents. Generally, a book or a year of a periodical fits on one fiche and takes 0.05% of the space and weight of the paper work.
• It is lower cost than a paper copy. Most microfiche services get a bulk discount on reproduction rights, and have lower reproduction costs than a comparable amount of printed paper ($5 per fiche in 2003).
• It is a stable archival form. Most library microfiche use polyester with silver-halide dyes in hard gelatin, with an estimated life of 500 years in air-conditioning. In tropical climates with high humidity, fungus eats the gelatin used to bind the silver-halide. In the tropics, diazo-based systems with lower archival lives (20 years) are preferable, because they have polyester or epoxy surfaces.
• Since it is analog (an actual image of the original data), it is easy to view. Unlike digital media, the data format is instantly comprehensible to persons literate in the language; the only additional equipment that is needed is a simple magnifying glass. This reduces the possibility of obsolescence.

Disadvantages

• The principal disadvantage of microfiche is that the image is too small to read with the naked eye. Libraries must use special readers that project full-size images on a ground-glass screen.
• A significant disadvantage is that when stored in the highest-density drawers, it is easy to misfile a fiche, which is thereafter unavailable. Some libraries therefore keep the microfiche cabinet in a restricted area, and fetch fiches on demand. Some fiche services use lower-density drawers with labelled pockets for each card.
• Another disadvantage is that a conventional photocopier cannot reproduce the images.

Libraries using microfiche often have a few viewers that can produce a photocopy of an image, for a nominal fee.

• The final disadvantage is that microfiche can only be reproduced a limited number of times, while data stored on digital media does not degenerate and control software often include error detection and correction schemes.

History

Originally most microfiche were produced by first making a microfilm with a microfilm camera. After developing the film, it was cut into short strips which were usually inserted by hand in a microfiche jacket. The jacket could then be reproduced any number of times.

In the 1970s and 1980s machines were developed which could produce microfiche directly from a computer peripheral. These microfiche were called COM, for Computer Output Microfiche. They were used to distribute massive amounts of frequently changed data to institutions or companies which could not afford computer terminals but already used microfiche readers for a variety of reasons. In some cases the quantities involved justified getting a microfiche reader just to read COM fiche.

External links

• The Library of Congress Photoduplication Service
• The Northeast Document Conservation Center
• U.S. Patent 3,185,026 Title: Method and Apparatus Employing Metachromatic Materials for Forming A Plurality of Individual Micro-Images issued May 25, 1965 Patent Assignee: National Cash Register Co. (NCR), Dayton, Ohio