Bend radius

About: Bend radius is a research topic. Over the lifetime, 3303 publications have been published within this topic receiving 35415 citations. The topic is also known as: minimum bend radius.

High density integrated optical chip

Abstract: A high density integrated optical chip (20). The optical chip features an optical function (26) connected to a low minimum bending radius dielectric waveguide (24), and a large mode field size dielectric waveguide (22) to interface with an external optical device (28), such as an optical fiber. The large mode field size dielectric waveguide is optically connected to the low minimum bending radius dielectric waveguide on the optical chip.

Small radius bends and large angle splitters in SOI waveguides

Abstract: The silicon/silicon dioxide (Si/SiO2) materials system provides a high index contrast waveguide platform compatible with existing monolithic microelectronic fabrication processes. The large index difference between the Si and SiO2 ((Delta) n approximately equals 2.0) allows the miniaturization of waveguide cross-sectional dimensions: single-mode strip waveguides with 0.2 X 0.5 micrometers cross-sections are possible. Additionally, right angle waveguide bends with radii of 2.0 micrometers can be fabricated with insertion loss of less than 1.0 dB. Bend radii of 250 micrometers or more are required to achieve the same performance in less confined waveguide systems such as GaAs/AlGaAs. The high confinement of the Si/SiO2 system also allows Y-branch power splitters with splitting angles greater than 20 degree(s) to operate with low loss. The combination of small cross- section, small bend radius, and large splitting angle provides a highly compact light guiding technology. Calculations of the loss due to 90 degree(s) bends in these waveguides and preliminary loss measurements for bends from 2.0 to 100.0 micrometers in radius are reported. Y-branch power splitters are analyzed and measurements of branches from 2 degree(s) to 40 degree(s) are presented.

Orbital Angular Momentum (OAM) Mode Mixing in a Bent Step Index Fiber in Perturbation Theory

Abstract: Within the framework of perturbation theory, we explore in detail the mixing of orbital angular momentum (OAM) modes due to a fiber bend in a step-index multimode fiber. Using a scalar wave equation, we develop a complete set of analytic expressions for modemixing, including those for the 2π walk-off length, which is the distance traveled within the bent fiber before an OAM mode transforms into its negative topological charge counterpart, and back into itself. The derived results provide insight into the nature of the bend effects, clearly revealing the mathematical dependence on the bend radius and the topological charge. We numerically simulate the theoretical results with applications to a few-mode fiber and a multimode fiber, and calculate bend-induced modal crosstalk with implications for mode-multiplexed systems. The presented perturbation technique is general enough to be applicable to other perturbations like ellipticity and easily extendable to other fibers with step-index-like profile as in the ring fiber.

Robust single-mode all-solid multi-trench fiber with large effective mode area

Abstract: We experimentally demonstrate all-solid 30 and 90 µm core diameter multi-trench fibers. Measurements ensure an effective single-mode operation over a wide range of bend radius in the case of 30 µm core fiber, making it suitable for applications like beam delivery and compact fiber lasers. On the other hand, a 90 µm core fiber ensures an effective single-mode operation and shows good potential for rod-type fiber laser applications. Both fibers were fabricated by the conventional modified chemical vapor deposition process in conjunction with the rod-in-tube technique, hence making them suitable for mass production.

Optical fiber cassette

Abstract: A cassette stores varying lengths of excess optical fiber defined during the installation of optical fiber cable. The cassette has two spools and numerous pathways for winding and storing excess optical fiber, while maintaining the minimum bend radius. Retainers hold the optical fiber in the pathways and on the spools. Two splice receptacles releasably retain splice connections. A tension wire tie-down is provided, having a variety of options for placement and direction, to clamp the optical fiber cable, and electrically ground the tension wires. Tabs are provided for releasably locking the hinged cover in the open and closed positions.