We use Optical Character Recognition (OCR) during our scanning and processing workflow to make the content of each page searchable. You can view the automatically generated text below as well as copy and paste individual pieces of text to quote in your own work.
Text recognition is never 100% accurate. Many parts of the scanned page may not be reflected in the OCR text output, including: images, page layout, certain fonts or handwriting.
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P. C. GOLDMARK
[J. S. M. P. E.
beam instead of further describing frame D, continues to scan frame E which is on its way down from position E to F. Again the scanning spot returns to the base-line of frame F with a rapid jump, while this frame proceeds to position G and is scanned from bottom to top within Vso of a second. Thus an entire cycle has been completed, consisting of the scanning of two motion picture frames five times each within Veo of a second, or the total operation completed in Vi2 of a second.
The scanning spot will now start to scan frame H which appears at
the top of the gate, and thus start a new cycle.
This principle can be applied in several ways in practice, some of which will be mentioned here. A luminous scanning pattern can be produced on the flat end of a highintensity cathode-ray tube which is projected through lenses onto the moving film. With a suitable condenser lens system, light emerging through the film is collected and projected into a multiplier type of photocell. An extra pah of deflecting coils or deflecting plates fed by a rectangular current or voltage displaces the luminous scanning pattern on the tube in such a fashion that various portions of the moving film are scanned hi accordance with Fig. 1. Although this method is theoretically correct, hi practice difficulties are encountered due to the fact that in order to obtain five congruent images, the scanning pattern as it jumps into various positions on the screen of the tube must maintain its shape within Viooo of its height and width. It is very difficult to produce a sufficiently homogeneous magnetic and electrical field that will produce identical images.
The thought occurs to produce a stationary scanning pattern and split it up into five images displaced in accordance with Fig. 1. To split up the original into five displaced images we can employ either five mirrors tilted at different angles or five lenses with their
FIG. 2. Schematic layout of scanner using five mirrors.