| 摘要 |
A high definition page display system for graphics and text utilizing shaped beams in a CRT is disclosed. Information for the several lines which are written simultaneously is made available in parallel. The invention is described in terms of a character set and text generation, but the same principles apply to any other graphic or bit map and to storage in ROMs or loadable RAMs. Each beam of a multiple CRT tube is biased to generate a portion of a character or grahic as it scans across the tube. It takes 12 lines to scan a character with a N-beam tube, 12 over N character scans are therefore required. With the same scanning speed as with a single beam, this factor can be used to increase definition (i.e. number of lines.) Also the advantage of multiple beams can be used to reduce scanning speed, if this is useful to improve brightness or spot definition, or to increase the number of dots per line. Reduced scanning speed can also reduce costs, particularly if it brings the scan rate in line with standard components available commercially. Another way to use the advantages would be higher refresh rates.
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