Liquid level sensor based on pof optical fiber macrobending

Abstract

The invention relates to a liquid level sensor based on POF (plastic optical fiber) optical fiber macrobending. The liquid level sensor comprises a single macrobending optical fiber annular structure and a fixing structure, wherein the single macrobending optical fiber annular structure is manufactured through bending POF bare optical fiber and has the top macrobending radius being 2.5mm, the top macrobending part of the single macrobending optical fiber annular structure is used as a probe, two tail ends of the POF bare optical fiber are provided with optical fiber joints, the fixing structure is used for encapsulating the single macrobending optical fiber annular structure, and the probe is exposed out from the fixing structure. The liquid level sensor has the advantages that the design of the single macrobending optical fiber annular structure is adopted, the optical fiber macrobending is singly used for enhancing the CMFTIR (cladding mode frustratedtotal internal reflection) effect, the distinction degree being 1.06dB is realized, and the liquid level measurement requirement is met. In addition, the double optical fiber coupling is not needed, so that the process difficulty is simplified, the structure is more compact, and the liquid level sensor is suitable for being used in a narrow space. Meanwhile, the liquid viscosity of an SMBFL (single macro-bend fiber loop) structure is low, the initial bath error is greatly reduced, the SMBFL directly detects bright field signals with higher power, and the requirement of long-distance transmission is met.

Description

technical field

[0001] The invention relates to a sensor, in particular to a liquid level sensor based on POF optical fiber macrobending. Background technique

[0002] Liquid level measurement has a very wide range of application requirements and huge market space in the chemical, chemical, and petroleum fields. Various designs emerge in endlessly, from the simplest oil dipstick to liquid level sensors with complex structures. At present, although there are liquid level sensors based on various principles, including magnetostrictive, capacitive, ultrasonic, and optical fiber, there are still prominent contradictions between liquid level measurement technology and market demand. , There are two main reasons: First, although the petrochemical industry has a huge demand for sensors, it is more sensitive to cost, and it is difficult for expensive and complex designs to be widely used in these fields. Second, the liquid level measurement environment in the chemical industry is c...

Examples

Embodiment Construction

[0023] A POF bare fiber 1 (Mitsubishi, SK-40) is used to bend the top macrobend bending radius (R / 2) of 2.5mm single macrobend fiber ring structure, and the top macrobend part is used as the probe 2, and the POF bare fiber There are standard FC optical fiber connectors at both ends of the optical fiber, and the optical fiber connectors are respectively connected to the light source 3 and the power meter 4 in the test system. A standard FC optical fiber connector protective sleeve accessory is used as the fixed structure 5, and the single macrobend optical fiber ring structure is encapsulated in the fixed structure 5 with silica gel or epoxy resin 6, and the probe 2 is exposed from the top of the fixed structure 5. The outside of the POF bare optical fiber 1 other than the fixed structure 5 and the probe 2 is wrapped with a black heat-shrinkable sleeve. Its structure is as figure 1 shown.

[0024] The fabricated SMBFL probe was subjected to a water immersion-outlet test. The...

technical field

[0001] The invention relates to a sensor, in particular to a liquid level sensor based on POF optical fiber macrobending. Background technique

[0002] Liquid level measurement has a very wide range of application requirements and huge market space in the chemical, chemical, and petroleum fields. Various designs emerge in endlessly, from the simplest oil dipstick to liquid level sensors with complex structures. At present, although there are liquid level sensors based on various principles, including magnetostrictive, capacitive, ultrasonic, and optical fiber, there are still prominent contradictions between liquid level measurement technology and market demand. , There are two main reasons: First, although the petrochemical industry has a huge demand for sensors, it is more sensitive to cost, and it is difficult for expensive and complex designs to be widely used in these fields. Second, the liquid level measurement environment in the chemical industry is c...

Examples

Embodiment Construction

[0023] A POF bare fiber 1 (Mitsubishi, SK-40) is used to bend the top macrobend bending radius (R / 2) of 2.5mm single macrobend fiber ring structure, and the top macrobend part is used as the probe 2, and the POF bare fiber There are standard FC optical fiber connectors at both ends of the optical fiber, and the optical fiber connectors are respectively connected to the light source 3 and the power meter 4 in the test system. A standard FC optical fiber connector protective sleeve accessory is used as the fixed structure 5, and the single macrobend optical fiber ring structure is encapsulated in the fixed structure 5 with silica gel or epoxy resin 6, and the probe 2 is exposed from the top of the fixed structure 5. The outside of the POF bare optical fiber 1 other than the fixed structure 5 and the probe 2 is wrapped with a black heat-shrinkable sleeve. Its structure is as figure 1 shown.

[0024] The fabricated SMBFL probe was subjected to a water immersion-outlet test. The...

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