Abstract We report a real-time and highly sensitive liquid level sensor based on multimode interference to acquire the level measurement of high-RI liquids, e.g. oil, which probably poses promising applications in the motor-dom. The level sensor is fabricated by fusion splicing a short section of NCF between two SMFs. Level measurement with both low-RI and high-RI liquids have been studied; it is found that the sensor shows the maximum sensitivity of ∼ −189.5 μ W/mm, corresponding to a level resolution of ∼ 0. 6 μ m in the range of 0 mm to 4 mm for high-RI liquids. In addition, experimental results have demonstrated that the proposed sensor shows good performance, thus providing a liquid level sensor that is inexpensive with a very simple fabrication process.

中文翻译：

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基于无芯光纤自成像效应的高折射率液体液位测量

摘要 我们报告了一种基于多模干扰的实时和高灵敏度液位传感器，用于获取高 RI 液体（例如油）的液位测量，这可能在电机领域具有广阔的应用前景。液位传感器是通过在两个 SMF 之间熔接一小段 NCF 来制造的。研究了低 RI 和高 RI 液体的液位测量；结果表明，该传感器的最大灵敏度为 ∼ -189.5 μ W/mm，对应于高 RI 液体在 0 mm 至 4 mm 范围内的 ∼ 0. 6 μ m 液位分辨率。此外，实验结果表明，所提出的传感器表现出良好的性能，从而提供了一种制造工艺非常简单且价格低廉的液位传感器。