Bent slab ray theory for power distribution in core and cladding of bent multimode optical fibres

Computational studies of light acceptance and propagation in straight and curved multimodal active fibres

“…This transmission function is shown in figure 10 as a dashed line and it overestimates the light losses due the larger axial angles allowed for skew rays. A comparable theoretical calculation using a two-dimensional slab model and a generalized Fresnel transmission coefficient has been performed by Badar et al [12]. Their plot of the power contained in the fibre core as a function of the radius of curvature ( figure 5) is similar to our results on the transmission function in the meridional approximation.…”

“…Those studies are difficult to extend to multimode fibres since a large number of guided modes has to be considered. When applying ray optics to curved multimode fibres the use of a two-dimensional model is common [11,12,13]. In contrast, our simulation method follows a three-dimensional approach.…”

“…Since then, the scientific and technological progress in the field of fibre optics has been enormous. Despite the extensive coverage of theory and experiment in this field, only fragmentary studies on the trapping efficiencies and refraction of skew rays in curved multimode fibres could be found [10,11,12,13]. We have therefore performed a three-dimensional simulation of photons propagating in simple circularly curved fibres in order to quantify the losses and to establish the dependence of these losses on the angle of the bend.…”

Lateral polishing of bends in plastic optical fibres applied to a multipoint liquid-level measurement sensor

“…Accordingly, numerous studies have been carried out to determine power loss caused by bent sections in single-mode [11,12] and in multimode fibres [13][14][15][16][17][18][19]. The former fibre type requires application of electromagnetic modal theory and adoption of simplified approaches.…”

Analysis of Radiation from Tapered Multimode Slab Waveguides by the Ray-Optics Approach

“…The ray theory analysis has an advantage in that it allows understanding of the physical picture. And he simplified two-dimensional multimode slab waveguide model can be used to describe an optical waveguide or a fiber surrounded by a thick cladding [7][8][9][10]. All optical ray paths are traced within the core region of the tapered structure, and then the radiation emitted from the core can be computed by taking account of the partial transmission of each non-total reflection at the interface between the core and the cladding.…”