Over the past thirty years, optical fibers have revolutionized the telecommunication market. Fiber optics play also important roles in other numerous applications. One of these applications is fiber sensing – very fast developing area. In this paper, realization of different configurations of a fiber optic sensor detecting the presence of liquid is presented. In the presented sensor, two multimode fibers (MMF) are placed opposite each other, where the first one transmits the light radiation, while the second one is a receiver. Due to the small size of the core (50 μm diameter), they had to be precisely positioned. Therefore the optical fibers were placed in the etched channels in the silicon substrate.
In order to make sensors more sensitive, ball-lensed optical fibers were used. Four different diameters of lenses were examined. Sensitivity to the presence of liquids was compared in all realized sensors. Moreover, the influence of distance between the transmitting and receiving optical fiber on the received optical power is also described in this paper. All developed sensors were tested at 1300 nm wavelength. In the last part of this paper the detailed discussion is given.
In almost all of non-invasive techniques, fiber optic sensors may be the most promising ones because of their inherent advantages such as very small size and hard environment tolerance. Proximity sensors based on optical fiber are highly required especially in the impact area of electromagnetic fields.
In this paper three different types of fiber optic reflective sensors are presented. In all three types of the sensor four multimode optical fibers (MMF) illuminate the movable surface. The difference is in the number of collecting the reflected light MMF. In the first one, 12 MMF collect the light, in the second one 20 MMF, while in the third one the number of MMF collecting reflected light is 32. Moreover, all three types of fiber optic reflective sensors were realized in two configurations. In the first one, the cleaved MMF were used to collect reflected light, while in the second configuration – the ball-lensed optical fibers were chosen. In this paper an analysis of each type of realized sensor is presented. In the last part of this paper the obtained results and the detailed discussion are given.
Reflective sensors involving optical fibers are very popular due to low cost and EMI insensitive. In this paper, a new
concept is described regarding proximity sensors based on ball-lensed optical fibers (PSBBOF). Two types of sensors are
presented: (1) Type A with one transmitting and four receiving optical fibers and (2) Type B with one transmitting and
eight receiving optical fibers. In both PSBBOF types ball-lensed optical fibers are used as a receiving line. Sensitive of
both PSBBOF is compared to sensitive of sensors with the same configurations, but involving cleaved optical fibers. All
developed sensors were tested at two wavelengths: 850 nm and 1300 nm. As a refractive surface the silicon wafer was
In this paper the specifics of FTTH (Fiber To The Home) networks in terms of requirements for optical fibers has been
presented. Optical fiber samples used in FTTH applications acquired from the worldwide leading manufacturers were
subjected to small diameter mandrel wraps tests. The detailed procedures of performed tests and the measurement results
has been presented.