| 摘要 |
PCT No. PCT/EP87/00458 Sec. 371 Date May 17, 1988 Sec. 102(e) Date May 17, 1988 PCT Filed Oct. 9, 1987 PCT Pub. No. WO88/02848 PCT Pub. Date Apr. 21, 1988.An absolute measuring scale system comprising a scale which extends along a measuring length, and a measuring head which is movable relative to the scale. The system further includes a fine-measurement sensor which is intended to measure the absolute values within each of a multiple of intervals lying sequentially along the scale, and a coarse-measurement sensor intended to measure the absolute values with regard to the interval within which the fine-measurement sensor is located at that moment. The invention is characterized in that the scale (2) comprises a carrier made of a transparent and form-stable material, preferably glass, which has provided on its surface an outer coating or layer which forms an opaque pattern (3, 4). The pattern formed along the length of the scale (2) forms transparent, mutually parallel binary code tracks (12), preferably in accordance with the so-called Grey-code. The measuring head includes light-emitting and light-sensitive devices, by means of which the measuring head is arranged to sense the code tracks, the coarse-measurement sensor including the code tracks (12) and the light-emitting and light-sensing devices. The pattern (3, 4) along the length of the scale (2) forms part of the sensor which is intended to co-act with the fine-measurement sensor.
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