Simultaneous Measurement of Seawater Temperature and Pressure With Polydimethylsiloxane Packaged Optical Microfiber Coupler Combined Sagnac Loop

Over 70% of the earth’s surface is covered by oceans; globally, oceans provides a huge source of wealth to humans. In the literature, several sensors have been developed to investigate oceans. Electrical conductivity temperature depth (CTD) sensors were used frequently and extensively. Long-term accurate CTD data is important for the study and utilization of oceans, e.g., for weather forecasting, ecological evolution, fishery, and shipping. Several kinds of CTD sensors based on electrics, optical, acoustic wave and radio waves have been developed. CTD sensors are often utilized by measuring electrical signals. The latest progress of CTD sensors will be presented in order of performance. The principles, structure, materials and properties of many CTD sensors were discussed in detail. The commercially available CTD sensors were involved and their respective performances were compared. Some possible development directions of CTD sensors for ocean investigation are proposed.

Section: Temperature Sensorsmentioning

confidence: 99%

CTD Sensors for Ocean Investigation Including State of Art and Commercially Available

Xiao

Zhang

Liu

et al. 2023

“…However, sensors based on TF are generally fragile, due to the waist diameter being down to the micron or even nanometer level. Thus, some protection and package measures must be considered, such as with the assistance of Polydimethylsiloxane (PDMS) [ 60 ].…”

Section: Sensors Based On Magnetic Fluid (Mf)mentioning

confidence: 99%

Research Progress on Magneto-Refractive Magnetic Field Fiber Sensors

Wei

Wang

et al. 2023

Self Cite

The magnetic field is a vital physical quantity in nature that is closely related to human production life. Magnetic field sensors (namely magnetometers) have significant application value in scientific research, engineering applications, industrial productions, and so forth. Accompanied by the continuous development of magnetic materials and fiber-sensing technology, fiber sensors based on the Magneto-Refractive Effect (MRE) not only take advantage in compact structure, superior performance, and strong environmental adaptability but also further meet the requirement of the quasi-distributed/distributed magnetic field sensing; they manifest potential and great application value in space detection, marine environmental monitoring, etc. Consequently, the present and prevalent Magneto-Refractive Magnetic Field Fiber Sensors (MR-MFSs) are briefly summarized by this paper, proceeding from the perspective of physicochemical properties; design methods, basic performance and properties are introduced systematically as well. Furthermore, this paper also summarizes key fabrication techniques and future development trends of MR-MFSs, expecting to provide ideas and technical references for staff engaging in relevant research.

“…So, some polymers with high TOC and high elasticity are used to cover the microfiber for this purpose, such as PDMS. For example, a PDMS-immersed OMC−Sagnac hybrid structure is proposed to realize simultaneous measurement of TP with sensitivities of −2.133 nm/°C and 3.416 nm/MPa [ 115 ]. Similarly, by immersing the whole in-line MMZI into PDMS, sensing of TP in seawater with high sensitivity can also be realized with sensitivities of −7.41 nm/°C and 13.31 nm/MPa, respectively ( Figure 5 c) [ 116 ].…”

Section: Ofs For Multi-parameter Sensing and Measurement In Tspmentioning

confidence: 99%

“…For example, Liu et al realized a response time of 33 ms in salinity sensing [ 104 ]; Hou et al obtained response times of 1.13 s and 286 ms in TP sensing [ 116 ]. In the TP sensing, Lu et al obtained response times of 2.6 s and 960 ms, respectively [ 115 ]. By optimizing the encapsulation, the response time after encapsulation of MMZI in TS sensing was about 219.0 ms and 12.5 ms, respectively [ 136 ].…”

Section: Practical Application Of Optical Fiber Sensors In Ocean Obse...mentioning

confidence: 99%

Review of Optical Fiber Sensors for Temperature, Salinity, and Pressure Sensing and Measurement in Seawater

Liang

Wang

Zhang

et al. 2022

Temperature, salinity, and pressure (TSP) are essential parameters for the ocean. Optical fiber sensors (OFSs) have rapidly come into focus as an ocean detection technology in recent years due to their advantages of electromagnetic interference, light weight, low cost, and no waterproof requirement. In this paper, the most recently developed TSP sensors for single parameter and multi-parameter TSP sensing and measurement based on different OFSs are reviewed. In addition, from the practical point of view, encapsulation methods that protect fibers and maintain the normal operation of OFSs in seawater, and the response time of the OFS, are addressed. Finally, we discuss the prospects and challenges of OFSs used in marine environments and provide some clues for future work.