求助位移传感器

  我正在做一个位移传感器，精度0.001mm，测量的量程50m左右，请大家帮忙，给个思路。

满量程精度：1/50000000。不是在梦中吧。。。

<br />容栅式传感器<br />&nbsp;&nbsp;&nbsp;下表为HY-65数码位移传感器和国内其他类型位移传感器以50mm量程为例（均以有关厂家公布的最佳主要技术参数，仅供参考）性能对照一览表：&nbsp;<br />&nbsp;<br /><table class=ubb cellspacing=0><TR><td class=ubb><br />传感器类别&nbsp;</td><td class=ubb><br />分<br />辨<br />度</td><td class=ubb><br />准确度<br />或示值<br />误差&nbsp;</td><td class=ubb><br />F.S.<br />线性<br />(%)&nbsp;</td><td class=ubb><br />F.S.<br />重复性<br />(%)&nbsp;</td><td class=ubb><br />F.S.<br />回差<br />（%）</td><td class=ubb><br />稳定性<br />时漂<br />温漂&nbsp;</td><td class=ubb><br />直接传送距离</td><td class=ubb><br />环境适应性(潮湿、温度、振动与冲击)&nbsp;</td><td class=ubb><br />需要2次仪表支持</td><td class=ubb><br />与计算机接&nbsp;口方式</td><td class=ubb><br />参考<br />售价<br />元/只</td></TR><TR><td class=ubb><br />光栅&nbsp;<br />&nbsp;</td><td class=ubb><br />0.02-1μm</td><td class=ubb><br />&lt0.005%<br />&lt1-10μm</td><td class=ubb><br />&lt0.005</td><td class=ubb><br />&lt0.002&nbsp;<br />&nbsp;</td><td class=ubb><br />&lt0.005&nbsp;<br />&nbsp;</td><td class=ubb><br />好&nbsp;<br />&nbsp;</td><td class=ubb><br />&lt10m&nbsp;<br />&nbsp;</td><td class=ubb><br />差&nbsp;<br />&nbsp;</td><td class=ubb><br />不需要&nbsp;<br />&nbsp;</td><td class=ubb><br />增量计<br />数码&nbsp;<br />&nbsp;</td><td class=ubb><br />约4000元<br />带显示器&nbsp;</td></TR><TR><td class=ubb><br />容栅&nbsp;<br />&nbsp;</td><td class=ubb><br />10<br />μm&nbsp;<br />&nbsp;</td><td class=ubb><br />&lt0.1%<br />&lt40μm&nbsp;<br />&nbsp;</td><td class=ubb><br />&lt0.1&nbsp;<br />&nbsp;</td><td class=ubb><br />&lt0.05&nbsp;<br />&nbsp;</td><td class=ubb><br />&lt0.1&nbsp;<br />&nbsp;</td><td class=ubb><br />好&nbsp;<br />&nbsp;</td><td class=ubb><br />&lt10m&nbsp;<br />&nbsp;</td><td class=ubb><br />差&nbsp;<br />&nbsp;</td><td class=ubb><br />不需要&nbsp;<br />&nbsp;</td><td class=ubb><br />数字接口连接方式复杂&nbsp;</td><td class=ubb><br />约500-<br />900元&nbsp;</td></TR><TR><td class=ubb><br />电感<br />调频&nbsp;<br />&nbsp;</td><td class=ubb><br />10<br />μm&nbsp;<br />&nbsp;</td><td class=ubb><br />不详&nbsp;<br />&nbsp;</td><td class=ubb><br />&lt0.1&nbsp;<br />&nbsp;</td><td class=ubb><br />&lt0.05&nbsp;<br />&nbsp;</td><td class=ubb><br />&lt0.025&nbsp;<br />&nbsp;</td><td class=ubb><br />较差&nbsp;<br />&nbsp;</td><td class=ubb><br />&lt100m&nbsp;<br />&nbsp;</td><td class=ubb><br />好&nbsp;<br />&nbsp;</td><td class=ubb><br />需要&nbsp;<br />&nbsp;</td><td class=ubb><br />频率信号&nbsp;<br />&nbsp;</td><td class=ubb><br />约600-<br />1200元&nbsp;</td></TR><TR><td class=ubb><br />电感差动变压器式</td><td class=ubb><br />1-10<br />μm&nbsp;<br />&nbsp;</td><td class=ubb><br />不详&nbsp;<br />&nbsp;</td><td class=ubb><br />&lt0.1<br />&lt0.05&nbsp;<br />&nbsp;</td><td class=ubb><br />&lt0.05<br />&lt0.025&nbsp;<br />&nbsp;</td><td class=ubb><br />&lt0.05<br />&lt0.025&nbsp;<br />&nbsp;</td><td class=ubb><br />一般&nbsp;<br />&nbsp;</td><td class=ubb><br />&lt100m&nbsp;<br />&nbsp;</td><td class=ubb><br />好&nbsp;<br />&nbsp;</td><td class=ubb><br />需要&nbsp;<br />&nbsp;</td><td class=ubb><br />模拟信号&nbsp;<br />&nbsp;</td><td class=ubb><br />约800-<br />1500元&nbsp;</td></TR><TR><td class=ubb><br />HY-65数码位移<br />传感器&nbsp;</td><td class=ubb><br />1μm&nbsp;<br />&nbsp;</td><td class=ubb><br />&lt0.05%<br />&lt0.1%<br />&nbsp;<br />&lt10-25μm&nbsp;<br />&nbsp;</td><td class=ubb><br />&lt0.025<br />&nbsp;<br />&lt0.05&nbsp;<br />&nbsp;</td><td class=ubb><br />&lt0.02<br />&nbsp;<br />&lt0.05&nbsp;<br />&nbsp;</td><td class=ubb><br />&lt0.025<br />&nbsp;<br />&lt0.05</td><td class=ubb><br />好&nbsp;<br />&nbsp;</td><td class=ubb><br />&gt1000m&nbsp;<br />&nbsp;</td><td class=ubb><br />好&nbsp;<br />&nbsp;</td><td class=ubb><br />不需要&nbsp;<br />&nbsp;</td><td class=ubb><br />RS-485或同步串行BCD码&nbsp;<br />&nbsp;</td><td class=ubb><br />约1200-<br />1800元&nbsp;<br />&nbsp;</td></TR><TR><td class=ubb><br />&nbsp;</td><td class=ubb><br />&nbsp;</td><td class=ubb><br />&nbsp;</td><td class=ubb><br />&nbsp;</td><td class=ubb><br />&nbsp;</td><td class=ubb><br />&nbsp;</td><td class=ubb><br />&nbsp;</td><td class=ubb><br />&nbsp;</td><td class=ubb><br />&nbsp;</td><td class=ubb><br />&nbsp;</td><td class=ubb><br />&nbsp;</td><td class=ubb><br />&nbsp;</td></TR></table>

如果没有几必须用上面兄弟的办法了