| 摘要 |
A continuous-tone thermal printer includes a transport mechanism for advancing a print medium past a thermal print head while continuous-tone image information is being printed, line-by-line, on the medium. To increase the rate at which thermal prints are produced, the printer includes asynchronous motor-control apparatus for selectively accelerating the movement of the print medium relative to the print head to quickly locate the print head at the start of a new image line immediately following the printing of that pixel(s) having the highest image density in the preceding image line. Preferably, such motor-control apparatus includes a digital signal processor which determines the maximum pixel density on each line. Upon printing such maximum pixel density, the digital signal processor causes a motor controller to temporarily increase the print medium velocity past the thermal print head to the start of the next image line.
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