Polymer optical fibers (POFs) doped with organic dyes can be used to make efficient lasers and amplifiers due to the high gains achievable in short distances. This paper analyzes the peculiarities of light amplification in POFs through some experimental data and a computational model capable of carrying out both power and spectral analyses. We investigate the emission spectral shifts and widths and on the optimum signal wavelength and pump power as functions of the fiber length, the fiber numerical aperture and the radial distribution of the dopant. Analyses for both step-index and graded-index POFs have been done.

In this work we analyze experimentally and theoretically the properties of amplified spontaneous emission (ASE) in a rhodamine-6G-doped graded-index polymer optical fiber. A theoretical model based on the laser rate equations describes the ASE features successfully. The dependence of the ASE threshold and efficiency on fiber length is analyzed in detail.

The emission properties of a graded-index thermoplastic polymer optical fiber and a step-index thermosetting one, both doped with rhodamine 6G, have been studied. The work includes a detailed analysis of the amplified spontaneous emission together with a study of the optical gains and losses of the fibers. The photostability of the emission of both types of fibers has also been investigated. Comparisons between the results of both doped polymer optical fibers are presented and discussed.

The chromatic dispersion and the refractive index of poly(methyl methacrylate) polymer optical fibers (POFs) have been characterized in this work by using a tunable femtosecond laser and a Streak Camera. The characterization technique is based on the measurement of the time delays of light pulses propagating along POFs at different wavelengths. Polymer fibers of three different lengths made by two manufacturers have been employed for that purpose, and discrepancies lower than 3% have been obtained in all cases.

The collection and interpretation of environmental data in a reliable and secure manner is of undeniable importance for the enhancement of healthcare quality and the mitigation of ecological risks associated with human activities. In pursuit of this objective, optical fibers have been utilized for several decades as a means of providing more flexible, compact, and cost-effective sensing platforms. Furthermore, the advent of technologies such as the laser, improved fabrication processes, and 3D printing has made it possible to engrave microstructures into optical fiber cores, resulting in a significant enhancement in sensitivity without compromising portability and compactness. The development of microstructured optical fibers (MOFs) has transformed the domain of optical sensing, as their distinctive capacity to confine and manipulate light surpasses that of conventional fibers. Their diverse structural configurations, encompassing fiber Bragg gratings, photonic crystal fibers, and tapered fibers, offer enhanced sensitivity and adaptability, rendering them invaluable in diverse applications. This review offers a comprehensive overview of recent advances in MOF technologies, emphasizing significant innovations in fiber design and fabrication and their influence on sensor performance over the past year. It is intended to serve as a comprehensive introductory resource for researchers and engineers, delineating the latest trends, technological advantages, and future directions in the rapidly evolving field of MOF-based sensors. Moreover, particular emphasis is placed on specific MOF types, including hollow-core and anti-resonant fibers, which have demonstrated considerable potential in environmental monitoring, biomedical sensing, and industrial applications. Additionally, the review encompasses the advancement of emerging structures, such as D-shaped and multicore fibers, which continue to challenge the limits of fiber-based sensors.

Mirrorless graded-index polymer optical fibers doped with the organic dye rhodamine 6G result in very compact broadband fiber lasers in the visible region when pumped from the side. The emission spectrum, threshold, and efficiency obtained on both fiber ends depend on the lengths of the directly illuminated region and of the non-excited ones. The paper analyzes such parameters both experimentally and theoretically for the first time.