Non-contact remote optical fiber displacement measurement device and measurement method thereof

Abstract

The present invention provides a non-contact remote optical fiber displacement measurement device and a machine measurement method thereof. The device comprises a photoelectric demodulation module, a transmitting optical cable, a receiving optical cable and a sensing lens. The sensing lens comprises a transmitting lens, a receiving lens, and a reflecting mirror facing the above lenses, wherein the transmitting lens and the receiving lens are arranged in parallel. The transmitting optical cable and the receiving optical cable are respectively and correspondingly connected with the transmitting lens and the receiving lens. The reflecting mirror is used for reflecting the light emitted from the transmitting lens to the rear surface of a target object. The scattered light is reflected by the reflecting mirror to shoot back to the receiving lens. According to the technical scheme of the invention, the positions of each of all the above lenses and a target plane in the sensing lens are set, and each lens is correspondingly connected with the transmitting optical cable, the receiving optical cable and the photoelectric demodulation module. The transmission of optical signals is realized through the optical cables, and an obtained optical fiber phase change amount is effectively deducted by the isolation method. Therefore, the influence of the surface reflection of optical elements on the signal light is avoided, while only the phase change between the lenses and the target plane in optical fibers is calculated to obtain a displacement change amount. Therefore, not only the debris shielding effect in an optical path is avoided, but also the long-distance low-loss transmission and anti-electromagnetic interference effect is realized. The obtained displacement information is high in reliability.

Description

technical field [0001] The invention relates to a displacement measuring device, in particular to an optical fiber displacement measuring device. Background technique [0002] At present, in the short-range displacement and distance measurement, microwave, electromagnetic wave radar, laser ranging and other methods are mostly used. These methods measure invisible, but their precision is poor, and the measurement accuracy is not enough. Especially in the measurement of liquid level, the geometric size of the transmitting and receiving devices is large, and it is not easy to use in some places where space is small. [0003] Capacitive and inductive measuring instruments and measuring methods are commonly used in liquid level measurement. There are many problems in the measurement accuracy and environmental tolerance of these methods, which are mainly reflected in the following aspects: (1) In the transmission of electrical signals, the interference that exists everywhere It ...

AI Technical Summary

Problems solved by technology

These methods measure invisible, but their accuracy is poor, and the measurement accuracy is not enough

Especially in the measurement of liquid level, the geometric size of the transmitting and receiving devices is large, which is not easy to use in some places with small spaces

[0003] Capacitance and inductance measuring instruments and measurement methods are commonly used in liquid level measurement. There are many problems in the measurement accuracy and environmental tolerance of these methods, which are mainly reflected in the following aspects: (1) In the transmission of electrical signals, interference exists everywhere It cannot be filtered cleanly, resulting in the measurement signal is not pure enough, so that the reliability of the demodulated data is not high; (2) The signal is easily distorted in harsh environments, which makes the deviation of the measurement result too large; (3) Existing displacement measurement equipment The signal is not easy to transmit over long distances

These problems make it impossible to measure accurately and reliably in liquid level and other measurement aspects.

[0004] However, with the needs of scientific research and production, there are also sensing systems based on optical methods to measure displacement. However, due to the integration of sensing and demodulation, the demodulation process is also vulnerable to environmental vibration and electromagnetic interference. The influence of the influence makes the reliability of the demodulated displacement information not high

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