Dual Self-Growing Polymer Microtips on a Multicore Fiber for Humidity and Temperature Discriminative Sensing

3D-Printed Ultracompact Multicore Fiber-Tip Probes for Simultaneous Measurement of Nanoforce and Temperature

“…The two probes can achieve enhanced shifts of the Vernier envelope with variations of applied force and temperature. The shifts of traced wavelength (Δλ) can be expressed as a function of the variation values of force (Δ F ) and temperature (Δ T ), as follows: [ lefttrue normalΔ λ cantilever normalΔ λ PDMS ] = [ lefttrue S cantilever F S cantilever T S PDMS F S PDMS T ] [ lefttrue normalΔ F normalΔ T ] where S F and S T are the force and temperature sensitivity coefficients of the two probes, respectively. Thus, the simultaneous measurement of nanoforce and temperature can be implemented to compensate for the influence of temperature perturbation on the measurement of nanoforce by using the two MCF-tip two probes.…”

“…In general, the stability of the sensitivity matrix can be evaluated by the condition number Cond 2 ( K ), which stands for the extent of the output value variation with slight changes in the input value. It can be expressed as , Con normald 2 ( K ) = || K || 2 || K − 1 || 2 where ∥ K ∥ 2 and ∥ K –1 ∥ 2 are the second-order norms of the sensitivity coefficient matrix K and the inverse sensitivity coefficient matrix K –1 , respectively. The condition number is 38.36 according to the calculation of the sensitivity coefficient matrix, indicating that the sensitivity matrix has good stability and that the proposed multiparameter sensor can accurately measure force and temperature simultaneously.…”

“…However, a wide range of temperature fluctuations can affect the printed components due to the polymer's intrinsic thermodynamic properties, 36 resulting in an inaccurate measurement. Although multiparameter measurement can be implemented by integrating multiple sensing components, such as the FBG and microcavity, into a single single-core fiber, 37,38 the different spatial location between the sensing components increases the size of the whole sensor, which may not be suitable for accurate measurement of multiple information on microscopic objects. The end facet of a multicore fiber (MCF) is arranged with multiple independent optical transmission channels, which is a powerful platform for manufacturing ultracompact probe-type sensors.…”

Applications and Development of Multi-Core Optical Fibers

“…In multi-core optical fiber point sensing, each channel can be used to measure a specific physical parameter at a particular position. By introducing different sensing mechanisms into different channels of the optical fiber, it can be employed to construct Fabry-Perot [48][49][50][51][52][53][54][55], Michelson [56][57][58][59][60], and Mach-Zehnder [61][62][63][64][65][66][67][68][69][70][71][72][73][74][75][76] interferometers, allowing independent measurements of physical parameters at specific locations. This enables real-time monitoring and perception of changes in physical parameters such as refractive index [56,57], temperature [48,[69][70][71][72][73], bending [51,61,62,77], and strain [50,[63][64][65].…”

“…The multi-channel nature of multi-core optical fibers can also facilitate the measurement of multiple physical parameters [52][53][54][66][67][68]74].…”