DATA STORAGE AND RETRIEVAL SYSTEM

摘要

A data storage and retrieval system is provided utilizing digital or analog data input signals to energize one or more data recording heads which can produce a selection of sizes of alphanumeric, pictorial ox digital coded images on a recording medium. Where alpha-numeric or pictorial images are produced, the images are both directly human and machine readable. Such alpha-numeric or pictorial images can be sequentially or simultaneously selectively produced full sized and/or reduced substantially in size to form at least 24:1 or greater size reductions of these images on the same or different recording media. Thus, for example, X-ray pictures or letters and the like can be simultaneously produced in reduced form on a microfilm recording medium for record storage purposes and full sized simultaneously of a recording medium for direct examination and delivery to third parties. The reduced data is directly human readable by projecting light preferably through the recording medium and magnifying and projecting the image on a screen. Alternatively, the data is machine readable a by scanning small segments of the image with a capacitance or resistance responsive or photo-electric display device, to develop electrical signals which can operate conventional display readout devices. The microfilm recording and electrical readout operations most advantageously are achieved by supporting the recording head or readout unit on a carrier which moves across the recorded area of the recording medium in a line-by-line scanning operation, carried out so rapidly that a complete page of information can be recorded upon the recording medium or read therefrom in at most a manner of a few seconds or less. In the most commercially significant form of the invention each data recording head capable of producing the reduced images is a Joule heat-producing device comprising one or more uniquely small current-carrying, heat-producing points each having dimensions preferably no greater than about 14 micron and less desirably no greater than about 20 micron. The heat-producing points are spaced about a distance no greater than about the aforesaid dimensions.