Cost-efficient speckle interferometry with plastic optical fiber for unobtrusive monitoring of human vital signs

A cost-efficient plastic optical fiber (POF) system for unobtrusive monitoring of human vital signs is presented. The system is based on speckle interferometry. A laser diode is butt-coupled to the POF whose exit face projects speckle patterns onto a linear Read More …

Focused ion beam post-processing of optical fiber Fabry-Perot cavities for sensing applications

Focused ion beam technology is combined with chemical etching of specifically designed fibers to create Fabry-Perot interferometers. Hydrofluoric acid is used to etch special fibers and create microwires with diameters of 15 ?m. These microwires are then milled with a Read More …

Monitoring and analysis of pendant droplets evaporation using bare and monolayer-coated optical fiber facets

The monitoring of sub nano-liter pendant liquid droplets, during their evaporation from the cleaved facet of a standard optical fiber, is proposed and demonstrated. The combined reflections of incident light from the two boundaries, between fiber and liquid and between Read More …

Miniature, all-fiber rotation sensor based on temperature compensated wave plate

This paper presents a miniature, all-fiber fiber optic twist/rotation sensor. The proposed sensor consists of polarization maintaining lead-in fiber (PMF), a short section of standard (fully circularly symmetric) single-mode fiber, which is exposed to twist/axial rotation, an all-fiber quarter-wave wave Read More …

In-line, fiber-optic polarimetric twist/torsion sensor

This letter presents an optical fiber twist/torsion sensor that utilizes dissimilar polarization-preserving characteristics of standard single-mode and high-birefringence fibers. When only one polarization mode of the highbirefringence fiber is excited, spatial orientation of the E-field vector follows the fiber’s principal Read More …

Nanowire-based refractive index sensor on the tip of an optical fiber

This letter presents a refractive index sensor created at the tip of an optical fiber that utilizes silica nanowire within a radius of between 225 nm and 600 nm, as a sensing element. Sensitivity in excess of 800 nm/RIU was Read More …

All-fiber, low-cost single-point and quasi-distributed evanescent field temperature sensors with extended temperature measurement range, based on standard telecommunication graded index fibers

Fiber-optic single-point and quasi-distributed evanescent temperature sensors recoated with a blend of poly(methyl methacrylate) and poly(vinylidene fluoride) are proposed. Solid cladding enables the construction of small-size, low-cost, relatively wide-range and fast-response temperature sensors. The diameter of the sensor does not Read More …