摘要 |
An optical detection system for a weighing scale includes an apparatus for generating a moire fringe. Unlike prior moire-type systems, however, the present scale is constructed with a substantially rigid tare, so that movement of the moire is limited to only a portion of one fringe line. Movement of the tare, and the pan carrying the load, are visually not apparent. Response time is greatly enhanced by the inventive system and accuracy is improved due to minimized hysteresis loss. The invention detects an optical shifting of the fringe line, rather than a counting of a number of fringe lines as with prior highly deflective scale systems.
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